Re: [RFC PATCH v5 6/9] media: tegra: Add Tegra210 Video input driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 3/25/20 4:03 AM, Sakari Ailus wrote:
External email: Use caution opening links or attachments


Hi Sowjanya,

Thanks for the patchset.

On Mon, Mar 23, 2020 at 10:52:32AM -0700, Sowjanya Komatineni wrote:
Tegra210 contains a powerful Video Input (VI) hardware controller
which can support up to 6 MIPI CSI camera sensors.

Each Tegra CSI port can be one-to-one mapped to VI channel and can
capture from an external camera sensor connected to CSI or from
built-in test pattern generator.

Tegra210 supports built-in test pattern generator from CSI to VI.

This patch adds a V4L2 media controller and capture driver support
for Tegra210 built-in CSI to VI test pattern generator.

Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
---
  drivers/staging/media/Kconfig              |    2 +
  drivers/staging/media/Makefile             |    1 +
  drivers/staging/media/tegra/Kconfig        |   10 +
  drivers/staging/media/tegra/Makefile       |    8 +
  drivers/staging/media/tegra/TODO           |   10 +
  drivers/staging/media/tegra/tegra-common.h |  263 +++++++
  drivers/staging/media/tegra/tegra-csi.c    |  522 ++++++++++++++
  drivers/staging/media/tegra/tegra-csi.h    |  118 ++++
  drivers/staging/media/tegra/tegra-vi.c     | 1058 ++++++++++++++++++++++++++++
  drivers/staging/media/tegra/tegra-vi.h     |   83 +++
  drivers/staging/media/tegra/tegra-video.c  |  129 ++++
  drivers/staging/media/tegra/tegra-video.h  |   32 +
  drivers/staging/media/tegra/tegra210.c     |  754 ++++++++++++++++++++
  drivers/staging/media/tegra/tegra210.h     |  192 +++++
Why staging? Are there reasons not to aim this to the kernel proper right
away? If you only support TPG, the driver may not have too many (if any)
real users anyway.

  14 files changed, 3182 insertions(+)
  create mode 100644 drivers/staging/media/tegra/Kconfig
  create mode 100644 drivers/staging/media/tegra/Makefile
  create mode 100644 drivers/staging/media/tegra/TODO
  create mode 100644 drivers/staging/media/tegra/tegra-common.h
  create mode 100644 drivers/staging/media/tegra/tegra-csi.c
  create mode 100644 drivers/staging/media/tegra/tegra-csi.h
  create mode 100644 drivers/staging/media/tegra/tegra-vi.c
  create mode 100644 drivers/staging/media/tegra/tegra-vi.h
  create mode 100644 drivers/staging/media/tegra/tegra-video.c
  create mode 100644 drivers/staging/media/tegra/tegra-video.h
  create mode 100644 drivers/staging/media/tegra/tegra210.c
  create mode 100644 drivers/staging/media/tegra/tegra210.h

diff --git a/drivers/staging/media/Kconfig b/drivers/staging/media/Kconfig
index e59a846..093a1a8 100644
--- a/drivers/staging/media/Kconfig
+++ b/drivers/staging/media/Kconfig
@@ -32,6 +32,8 @@ source "drivers/staging/media/omap4iss/Kconfig"

  source "drivers/staging/media/sunxi/Kconfig"

+source "drivers/staging/media/tegra/Kconfig"
+
  source "drivers/staging/media/tegra-vde/Kconfig"

  source "drivers/staging/media/ipu3/Kconfig"
diff --git a/drivers/staging/media/Makefile b/drivers/staging/media/Makefile
index 23c6824..586a590 100644
--- a/drivers/staging/media/Makefile
+++ b/drivers/staging/media/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_VIDEO_IMX_MEDIA) += imx/
  obj-$(CONFIG_VIDEO_MESON_VDEC)       += meson/vdec/
  obj-$(CONFIG_VIDEO_OMAP4)    += omap4iss/
  obj-$(CONFIG_VIDEO_SUNXI)    += sunxi/
+obj-$(CONFIG_VIDEO_TEGRA)    += tegra/
  obj-$(CONFIG_TEGRA_VDE)              += tegra-vde/
  obj-$(CONFIG_VIDEO_HANTRO)   += hantro/
  obj-$(CONFIG_VIDEO_IPU3_IMGU)        += ipu3/
diff --git a/drivers/staging/media/tegra/Kconfig b/drivers/staging/media/tegra/Kconfig
new file mode 100644
index 0000000..8bead1c
--- /dev/null
+++ b/drivers/staging/media/tegra/Kconfig
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config VIDEO_TEGRA
+     tristate "NVIDIA Tegra VI driver"
+     depends on ARCH_TEGRA || (ARM && COMPILE_TEST)
+     depends on VIDEO_V4L2
+     depends on MEDIA_CONTROLLER
+     select TEGRA_HOST1X
+     select VIDEOBUF2_DMA_CONTIG
+     help
+       Say yes here to enable support for Tegra video input hardware
diff --git a/drivers/staging/media/tegra/Makefile b/drivers/staging/media/tegra/Makefile
new file mode 100644
index 0000000..488c6ef
--- /dev/null
+++ b/drivers/staging/media/tegra/Makefile
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0
+tegra-video-y := \
+             tegra-video.o \
+             tegra-vi.o \
+             tegra-csi.o \
+             tegra210.o
+
+obj-$(CONFIG_VIDEO_TEGRA) += tegra-video.o
diff --git a/drivers/staging/media/tegra/TODO b/drivers/staging/media/tegra/TODO
new file mode 100644
index 0000000..d7d64b1
--- /dev/null
+++ b/drivers/staging/media/tegra/TODO
@@ -0,0 +1,10 @@
+TODO list
+* Currently driver supports Tegra build-in TPG Only with direct media links from CSI to VI.
+  Update the driver to do TPG Vs Sensor media links based on the kernel config CONFIG_VIDEO_TEGRA_TPG.
+* Add real camera sensor capture support
+* Add RAW10 packed video format support to Tegra210 video formats
+* Add Tegra CSI MIPI pads calibration
+* Add MIPI clock Settle time computation based on the data rate
+* Add support for Ganged mode
+* Make sure v4l2-compliance tests pass with all of the above implementations.
+* Add SMMU support for VI to avoid cma_alloc failures with higher resolutions of some video formats.
Please wrap at 80.

diff --git a/drivers/staging/media/tegra/tegra-common.h b/drivers/staging/media/tegra/tegra-common.h
new file mode 100644
index 0000000..966ad30
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra-common.h
@@ -0,0 +1,263 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#ifndef __TEGRA_COMMON_H__
+#define __TEGRA_COMMON_H__
+
+#include <linux/host1x.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+
+#include <media/media-device.h>
+#include <media/media-entity.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-subdev.h>
+#include <media/videobuf2-v4l2.h>
+
+#include "tegra-vi.h"
+#include "tegra-csi.h"
+
+#define TEGRA_MIN_WIDTH              32U
+#define TEGRA_MAX_WIDTH              32768U
+#define TEGRA_MIN_HEIGHT     32U
+#define TEGRA_MAX_HEIGHT     32768U
+
+#define TEGRA_DEF_WIDTH              1920
+#define TEGRA_DEF_HEIGHT     1080
+#define TEGRA_IMAGE_FORMAT_DEF       32
+
+#define MAX_FORMAT_NUM               64
+
+/*
+ * VI channel input data type enum.
+ * These data type enum value gets programmed into corresponding Tegra VI
+ * channel register bits.
+ */
+enum tegra_image_dt {
+     TEGRA_IMAGE_DT_YUV420_8 = 24,
+     TEGRA_IMAGE_DT_YUV420_10,
+
+     TEGRA_IMAGE_DT_YUV420CSPS_8 = 28,
+     TEGRA_IMAGE_DT_YUV420CSPS_10,
+     TEGRA_IMAGE_DT_YUV422_8,
+     TEGRA_IMAGE_DT_YUV422_10,
+     TEGRA_IMAGE_DT_RGB444,
+     TEGRA_IMAGE_DT_RGB555,
+     TEGRA_IMAGE_DT_RGB565,
+     TEGRA_IMAGE_DT_RGB666,
+     TEGRA_IMAGE_DT_RGB888,
+
+     TEGRA_IMAGE_DT_RAW6 = 40,
+     TEGRA_IMAGE_DT_RAW7,
+     TEGRA_IMAGE_DT_RAW8,
+     TEGRA_IMAGE_DT_RAW10,
+     TEGRA_IMAGE_DT_RAW12,
+     TEGRA_IMAGE_DT_RAW14,
+};
+
+/*
+ * Pixel memory format enum for Tegra VI channel.
+ * These format enum value gets programmed into corresponding Tegra VI
+ * channel register bits.
+ */
+enum tegra_image_format {
+     TEGRA_IMAGE_FORMAT_T_L8 = 16,
+
+     TEGRA_IMAGE_FORMAT_T_R16_I = 32,
+     TEGRA_IMAGE_FORMAT_T_B5G6R5,
+     TEGRA_IMAGE_FORMAT_T_R5G6B5,
+     TEGRA_IMAGE_FORMAT_T_A1B5G5R5,
+     TEGRA_IMAGE_FORMAT_T_A1R5G5B5,
+     TEGRA_IMAGE_FORMAT_T_B5G5R5A1,
+     TEGRA_IMAGE_FORMAT_T_R5G5B5A1,
+     TEGRA_IMAGE_FORMAT_T_A4B4G4R4,
+     TEGRA_IMAGE_FORMAT_T_A4R4G4B4,
+     TEGRA_IMAGE_FORMAT_T_B4G4R4A4,
+     TEGRA_IMAGE_FORMAT_T_R4G4B4A4,
+
+     TEGRA_IMAGE_FORMAT_T_A8B8G8R8 = 64,
+     TEGRA_IMAGE_FORMAT_T_A8R8G8B8,
+     TEGRA_IMAGE_FORMAT_T_B8G8R8A8,
+     TEGRA_IMAGE_FORMAT_T_R8G8B8A8,
+     TEGRA_IMAGE_FORMAT_T_A2B10G10R10,
+     TEGRA_IMAGE_FORMAT_T_A2R10G10B10,
+     TEGRA_IMAGE_FORMAT_T_B10G10R10A2,
+     TEGRA_IMAGE_FORMAT_T_R10G10B10A2,
+
+     TEGRA_IMAGE_FORMAT_T_A8Y8U8V8 = 193,
+     TEGRA_IMAGE_FORMAT_T_V8U8Y8A8,
+
+     TEGRA_IMAGE_FORMAT_T_A2Y10U10V10 = 197,
+     TEGRA_IMAGE_FORMAT_T_V10U10Y10A2,
+     TEGRA_IMAGE_FORMAT_T_Y8_U8__Y8_V8,
+     TEGRA_IMAGE_FORMAT_T_Y8_V8__Y8_U8,
+     TEGRA_IMAGE_FORMAT_T_U8_Y8__V8_Y8,
+     TEGRA_IMAGE_FORMAT_T_V8_Y8__U8_Y8,
+
+     TEGRA_IMAGE_FORMAT_T_Y8__U8__V8_N444 = 224,
+     TEGRA_IMAGE_FORMAT_T_Y8__U8V8_N444,
+     TEGRA_IMAGE_FORMAT_T_Y8__V8U8_N444,
+     TEGRA_IMAGE_FORMAT_T_Y8__U8__V8_N422,
+     TEGRA_IMAGE_FORMAT_T_Y8__U8V8_N422,
+     TEGRA_IMAGE_FORMAT_T_Y8__V8U8_N422,
+     TEGRA_IMAGE_FORMAT_T_Y8__U8__V8_N420,
+     TEGRA_IMAGE_FORMAT_T_Y8__U8V8_N420,
+     TEGRA_IMAGE_FORMAT_T_Y8__V8U8_N420,
+     TEGRA_IMAGE_FORMAT_T_X2LC10LB10LA10,
+     TEGRA_IMAGE_FORMAT_T_A2R6R6R6R6R6,
+};
+
+/**
+ * struct tegra_video_format - Tegra video format description
+ * @img_dt: image data type
+ * @bit_width: format width in bits per component
+ * @code: media bus format code
+ * @bpp: bytes per pixel (when stored in memory)
+ * @img_fmt: image format
+ * @fourcc: V4L2 pixel format FCC identifier
+ */
+struct tegra_video_format {
+     enum tegra_image_dt img_dt;
+     unsigned int bit_width;
+     unsigned int code;
+     unsigned int bpp;
+     u32 img_fmt;
+     u32 fourcc;
+};
+
+#define TEGRA_VIDEO_FORMAT(DATA_TYPE, BIT_WIDTH, MBUS_CODE, BPP,     \
+                        FORMAT, FOURCC)                              \
+{                                                                    \
+     TEGRA_IMAGE_DT_##DATA_TYPE,                                     \
+     BIT_WIDTH,                                                      \
+     MEDIA_BUS_FMT_##MBUS_CODE,                                      \
+     BPP,                                                            \
+     TEGRA_IMAGE_FORMAT_##FORMAT,                                    \
+     V4L2_PIX_FMT_##FOURCC,                                          \
+}
+
+enum tegra_vi_pg_mode {
+     TEGRA_VI_PG_DISABLED = 0,
+     TEGRA_VI_PG_DIRECT,
+     TEGRA_VI_PG_PATCH,
+};
+
+/**
+ * struct tegra_vi_channel - Tegra video channel
+ *
+ * @list: list head for this entry
+ * @video: V4L2 video device associated with the video channel
+ * @video_lock: protects the @format and @queue fields
+ * @pad: media pad for the video device entity
+ *
+ * @vi: Tegra video input device structure
+ * @frame_start_sp: host1x syncpoint pointer to synchronize programmed capture
+ *           start condition with hardware frame start events through host1x
+ *           syncpoint counters.
+ * @mw_ack_sp: host1x syncpoint pointer to synchronize programmed memory write
+ *           ack trigger condition with hardware memory write done at end of
+ *           frame through host1x syncpoint counters.
+ * @capture_reqs: capture requests initiated.
+ * @sp_incr_lock: protects cpu syncpoint increment.
+ *
+ * @kthread_start_capture: kthread to start capture of single frame when
+ *           vb buffer is available. This thread programs VI CSI hardware
+ *           for single frame capture and waits for frame start event from
+ *           the hardware. On receiving frame start event, it wakes up
+ *           kthread_finish_capture thread to wait for finishing frame data
+ *           write to the memory. In case of missing frame start event, this
+ *           thread returns buffer back to vb with VB2_BUF_STATE_ERROR.
+ * @start_wait: waitqueue for starting frame capture when buffer is available.
+ * @kthread_finish_capture: kthread to finish the buffer capture and return to.
+ *           This thread is woken up by kthread_start_capture on receiving
+ *           frame start event from the hardware and this thread waits for
+ *           MW_ACK_DONE event which indicates completion of writing frame
+ *           data to the memory. On receiving MW_ACK_DONE event, buffer is
+ *           returned back to vb with VB2_BUF_STATE_DONE and in case of
+ *           missing MW_ACK_DONE event, buffer is returned back to vb with
+ *           VB2_BUF_STATE_ERROR.
+ * @done_wait: waitqueue for finishing capture data writes to memory.
+ *
+ * @format: active V4L2 pixel format
+ * @fmtinfo: format information corresponding to the active @format
+ * @queue: vb2 buffers queue
+ * @sequence: V4L2 buffers sequence number
+ *
+ * @capture: list of queued buffers for capture
+ * @start_lock: protects the capture queued list
+ * @done: list of capture done queued buffers
+ * @done_lock: protects the capture done queue list
+ *
+ * @portno: VI channel port number
+ *
+ * @ctrl_handler: V4L2 control handler of this video channel
+ * @tpg_fmts_bitmap: a bitmap for supported TPG formats
+ * @pg_mode: test pattern generator mode (disabled/direct/patch)
+ */
+struct tegra_vi_channel {
+     struct list_head list;
+     struct video_device *video;
+     /* protects the @format and @queue fields */
+     struct mutex video_lock;
+     struct media_pad pad;
+
+     struct tegra_vi *vi;
+     struct host1x_syncpt *frame_start_sp;
+     struct host1x_syncpt *mw_ack_sp;
+     int capture_reqs;
+     /* protects the cpu syncpoint increment */
+     spinlock_t sp_incr_lock;
+
+     struct task_struct *kthread_start_capture;
+     wait_queue_head_t start_wait;
+     struct task_struct *kthread_finish_capture;
+     wait_queue_head_t done_wait;
+
+     struct v4l2_pix_format format;
+     const struct tegra_video_format *fmtinfo;
+     struct vb2_queue queue;
+     u32 sequence;
+
+     struct list_head capture;
+     /* protects the capture queued list */
+     spinlock_t start_lock;
+     struct list_head done;
+     /* protects the capture done queue list */
+     spinlock_t done_lock;
+
+     unsigned char portno;
+
+     struct v4l2_ctrl_handler ctrl_handler;
+     DECLARE_BITMAP(tpg_fmts_bitmap, MAX_FORMAT_NUM);
+     enum tegra_vi_pg_mode pg_mode;
+};
+
+/**
+ * struct tegra_channel_buffer - video channel buffer
+ * @buf: vb2 buffer base object
+ * @queue: buffer list entry in the channel queued buffers list
+ * @chan: channel that uses the buffer
+ * @addr: Tegra IOVA buffer address for VI output
+ * @mw_ack_sp_thresh: MW_ACK_DONE syncpoint threshold corresponding
+ *                 to the capture buffer.
+ */
+struct tegra_channel_buffer {
+     struct vb2_v4l2_buffer buf;
+     struct list_head queue;
+     struct tegra_vi_channel *chan;
+     dma_addr_t addr;
+     u32 mw_ack_sp_thresh;
+};
+
+int tegra_channel_setup_ctrl_handler(struct tegra_vi_channel *chan);
+int tegra_channel_set_stream(struct tegra_vi_channel *chan, bool on);
+void tegra_channel_release_buffers(struct tegra_vi_channel *chan,
+                                enum vb2_buffer_state state);
+int tegra_channel_csi_error_recover(struct tegra_vi_channel *chan);
+
+#endif
diff --git a/drivers/staging/media/tegra/tegra-csi.c b/drivers/staging/media/tegra/tegra-csi.c
new file mode 100644
index 0000000..338e7da
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra-csi.c
@@ -0,0 +1,522 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#include <linux/clk.h>
+#include <linux/clk/tegra.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/host1x.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "tegra-video.h"
+#include "tegra-common.h"
+#include "tegra-csi.h"
+
+#define TEGRA210_TPG_CLOCK                   594000000
+
+static inline struct tegra_csi *
+host1x_client_to_csi(struct host1x_client *client)
+{
+     return container_of(client, struct tegra_csi, client);
+}
+
+static inline struct tegra_csi_channel *to_csi_chan(struct v4l2_subdev *subdev)
+{
+     return container_of(subdev, struct tegra_csi_channel, subdev);
+}
+
+/*
+ * Only use this subdevice media bus ops for test pattern generator,
+ * because CSI device is an separated subdevice which has 6 source
+ * pads to generate test pattern.
+ */
+static const struct v4l2_mbus_framefmt tegra_csi_tpg_fmts[] = {
+     {
+             TEGRA_DEF_WIDTH,
+             TEGRA_DEF_HEIGHT,
+             MEDIA_BUS_FMT_SRGGB10_1X10,
+             V4L2_FIELD_NONE,
+             V4L2_COLORSPACE_SRGB
+     },
+     {
+             TEGRA_DEF_WIDTH,
+             TEGRA_DEF_HEIGHT,
+             MEDIA_BUS_FMT_RGB888_1X32_PADHI,
+             V4L2_FIELD_NONE,
+             V4L2_COLORSPACE_SRGB
+     }
+
+};
+
+static const struct v4l2_frmsize_discrete tegra_csi_tpg_sizes[] = {
+     { 1280, 720 },
+     { 1920, 1080 },
+     { 3840, 2160 },
+};
+
+/*
+ * V4L2 Subdevice Video Operations
+ */
+static int tegra_csi_s_stream(struct v4l2_subdev *subdev, int enable)
+{
+     struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
+     struct tegra_csi *csi = csi_chan->csi;
+     struct tegra_vi_channel *chan = subdev->host_priv;
+
+     return csi->ops->csi_streaming(csi_chan, chan->pg_mode, enable);
+}
+
+/*
+ * V4L2 Subdevice Pad Operations
+ */
+
+static int tegra_csi_enum_bus_code(struct v4l2_subdev *subdev,
+                                struct v4l2_subdev_pad_config *cfg,
+                                struct v4l2_subdev_mbus_code_enum *code)
+{
+     if (code->index >= ARRAY_SIZE(tegra_csi_tpg_fmts))
+             return -EINVAL;
+
+     code->code = tegra_csi_tpg_fmts[code->index].code;
+     return 0;
+}
+
+static int tegra_csi_get_format(struct v4l2_subdev *subdev,
+                             struct v4l2_subdev_pad_config *cfg,
+                             struct v4l2_subdev_format *fmt)
+{
+     struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
+
+     fmt->format = csi_chan->format;
+     return 0;
+}
+
+static void tegra_csi_try_mbus_fmt(struct v4l2_subdev *subdev,
+                                struct v4l2_mbus_framefmt *mfmt)
+{
+     struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
+     struct tegra_csi *csi = csi_chan->csi;
+     const struct v4l2_frmsize_discrete *sizes;
+     const struct v4l2_mbus_framefmt *mbus_fmt;
+     unsigned int i, j;
+
+     for (i = 0; i < ARRAY_SIZE(tegra_csi_tpg_fmts); i++) {
+             mbus_fmt = &tegra_csi_tpg_fmts[i];
+
+             if (mfmt->code != mbus_fmt->code)
+                     continue;
+
+             for (j = 0; j < ARRAY_SIZE(tegra_csi_tpg_sizes); j++) {
+                     sizes = &tegra_csi_tpg_sizes[j];
+                     if (mfmt->width == sizes->width &&
+                         mfmt->height == sizes->height) {
+                             return;
This only returns something sensible if you have an exact size (or close to
1920x1080). Please use v4l2_find_nearest_size(), for instance.

+                     }
+             }
+     }
+
+     dev_dbg(csi->dev, "using Tegra default format SRGGB10 1920x1080\n");
+     *mfmt = tegra_csi_tpg_fmts[0];
+}
+
+static int tegra_csi_set_format(struct v4l2_subdev *subdev,
+                             struct v4l2_subdev_pad_config *cfg,
+                             struct v4l2_subdev_format *fmt)
+{
+     struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
+     struct v4l2_mbus_framefmt *format = &fmt->format;
+
+     tegra_csi_try_mbus_fmt(subdev, format);
+
+     if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
+             return 0;
+
+     csi_chan->format = *format;
+     return 0;
+}
+
+/*
+ * V4L2 Subdevice Operations
+ */
+static struct v4l2_subdev_video_ops tegra_csi_video_ops = {
+     .s_stream = tegra_csi_s_stream,
+};
+
+static struct v4l2_subdev_pad_ops tegra_csi_pad_ops = {
+     .enum_mbus_code         = tegra_csi_enum_bus_code,
+     .get_fmt                = tegra_csi_get_format,
+     .set_fmt                = tegra_csi_set_format,
+};
+
+static struct v4l2_subdev_ops tegra_csi_ops = {
+     .video  = &tegra_csi_video_ops,
+     .pad    = &tegra_csi_pad_ops,
+};
const for the above.

+
+static int tegra_csi_tpg_channels_alloc(struct tegra_csi *csi)
+{
+     struct device_node *node = csi->dev->of_node;
+     unsigned int port_num;
+     struct tegra_csi_channel *chan;
+     unsigned int tpg_channels = csi->soc->csi_max_channels;
+
+     /* allocate CSI channel for each CSI x2 ports */
+     for (port_num = 0; port_num < tpg_channels; port_num++) {
+             chan = kzalloc(sizeof(*chan), GFP_KERNEL);
As there's a static number of these, I'd try to allocate them as part of
the main device context struct. That decreases the probability of leaking
memory; error handling remains complex enough in any case.

Sensor support will be added later to the same driver and when in non-tpg, channel allocations are based on ports info in device tree where not all channels are needed to be created a head.

+             if (!chan)
+                     return -ENOMEM;
+
+             list_add_tail(&chan->list, &csi->csi_chans);
+             chan->csi = csi;
+             chan->csi_port_num = port_num;
+             chan->numlanes = 2;
+             chan->of_node = node;
+             chan->numpads = 1;
+             chan->pads[0].flags = MEDIA_PAD_FL_SOURCE;
+     }
+
+     return 0;
+}
+
+static int tegra_csi_channel_init(struct tegra_csi_channel *chan)
+{
+     struct tegra_csi *csi = chan->csi;
+     struct v4l2_subdev *subdev;
+     int ret;
+
+     /* initialize the default format */
+     chan->format.code = MEDIA_BUS_FMT_SRGGB10_1X10;
+     chan->format.field = V4L2_FIELD_NONE;
+     chan->format.colorspace = V4L2_COLORSPACE_SRGB;
+     chan->format.width = TEGRA_DEF_WIDTH;
+     chan->format.height = TEGRA_DEF_HEIGHT;
+
+     /* initialize V4L2 subdevice and media entity */
+     subdev = &chan->subdev;
+     v4l2_subdev_init(subdev, &tegra_csi_ops);
+     subdev->dev = csi->dev;
+     snprintf(subdev->name, V4L2_SUBDEV_NAME_SIZE, "%s-%d", "tpg",
+              chan->csi_port_num);
+
+     v4l2_set_subdevdata(subdev, chan);
+     subdev->fwnode = of_fwnode_handle(chan->of_node);
+     subdev->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
+
+     /* initialize media entity pads */
+     ret = media_entity_pads_init(&subdev->entity, chan->numpads,
+                                  chan->pads);
+     if (ret < 0) {
+             dev_err(csi->dev,
+                     "failed to initialize media entity: %d\n", ret);
+             goto error;
+     }
+
+     return 0;
+
+error:
+     subdev = NULL;
+     return ret;
+}
+
+void tegra_csi_error_recover(struct v4l2_subdev *subdev)
+{
+     struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
+     struct tegra_csi *csi = csi_chan->csi;
+
+     csi->ops->csi_err_recover(csi_chan);
+}
+
+static void tegra_csi_channels_cleanup(struct tegra_csi *csi)
+{
+     struct v4l2_subdev *subdev;
+     struct tegra_csi_channel *chan, *tmp;
+
+     list_for_each_entry_safe(chan, tmp, &csi->csi_chans, list) {
+             subdev = &chan->subdev;
+             if (subdev)
+                     media_entity_cleanup(&subdev->entity);
+             list_del(&chan->list);
+             kfree(chan);
+     }
+}
+
+static int tegra_csi_init(struct host1x_client *client)
+{
+     struct tegra_csi *csi = host1x_client_to_csi(client);
+     struct tegra_video_device *vid = dev_get_drvdata(client->host);
+     struct tegra_csi_channel *chan;
+     int ret;
+
+     vid->csi = csi;
+
+     INIT_LIST_HEAD(&csi->csi_chans);
+
+     ret = tegra_csi_tpg_channels_alloc(csi);
+     if (ret < 0)
+             goto cleanup;
+
+     list_for_each_entry(chan, &csi->csi_chans, list) {
+             ret = tegra_csi_channel_init(chan);
+             if (ret) {
+                     dev_err(csi->dev, "channel init failed: %d\n", ret);
+                     goto cleanup;
+             }
+     }
+
+     ret = csi->ops->hw_init(csi);
+     if (ret)
+             goto cleanup;
+
+     ret = pm_runtime_get_sync(csi->dev);
+     if (ret < 0) {
pm_runtime_put_noidle()

+             dev_err(csi->dev, "runtime resume failed: %d\n", ret);
+             goto cleanup;
+     }
+
+     return 0;
+
+cleanup:
+     tegra_csi_channels_cleanup(csi);
+     return ret;
+}
+
+static int tegra_csi_exit(struct host1x_client *client)
+{
+     struct tegra_csi *csi = host1x_client_to_csi(client);
+     struct tegra_video_device *vid = dev_get_drvdata(client->host);
+
+     if (!vid->csi)
+             return 0;
+
+     pm_runtime_put_sync(csi->dev);
+     tegra_csi_channels_cleanup(csi);
+
+     return 0;
+}
+
+static const struct host1x_client_ops csi_client_ops = {
+     .init = tegra_csi_init,
+     .exit = tegra_csi_exit,
+};
+
+static int tegra_csi_probe(struct platform_device *pdev)
+{
+     struct tegra_csi *csi;
+     struct resource *res;
+     int ret;
+
+     csi = kzalloc(sizeof(*csi), GFP_KERNEL);
+     if (!csi)
+             return -ENOMEM;
+
+     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+     csi->iomem = devm_ioremap_resource(&pdev->dev, res);
+     if (IS_ERR(csi->iomem)) {
+             ret = PTR_ERR(csi->iomem);
+             goto cleanup;
+     }
+
+     csi->soc = of_device_get_match_data(&pdev->dev);
+     if (!csi->soc) {
+             ret = -ENODATA;
+             goto cleanup;
+     }
+
+     if (!pdev->dev.pm_domain) {
+             ret = -ENOENT;
+             dev_warn(&pdev->dev, "PM domain is not attached: %d\n", ret);
+             goto cleanup;
+     }
+
+     csi->dev = &pdev->dev;
+     csi->ops = csi->soc->ops;
+     platform_set_drvdata(pdev, csi);
+     pm_runtime_enable(&pdev->dev);
+
+     /* initialize host1x interface */
+     INIT_LIST_HEAD(&csi->client.list);
+     csi->client.ops = &csi_client_ops;
+     csi->client.dev = &pdev->dev;
+
+     ret = host1x_client_register(&csi->client);
+     if (ret < 0) {
+             dev_err(csi->dev,
+                     "failed to register host1x client: %d\n", ret);
+             ret = -ENODEV;
+             goto rpm_disable;
+     }
+
+     return 0;
+
+rpm_disable:
+     pm_runtime_disable(&pdev->dev);
+cleanup:
+     kfree(csi);
+     return ret;
+}
+
+static int tegra_csi_remove(struct platform_device *pdev)
+{
+     struct tegra_csi *csi = platform_get_drvdata(pdev);
+     int err;
+
+     pm_runtime_disable(csi->dev);
+
+     err = host1x_client_unregister(&csi->client);
+     if (err < 0) {
+             dev_err(csi->dev,
+                     "failed to unregister host1x client: %d\n", err);
+             return err;
+     }
+
+     kfree(csi);
+
+     return 0;
+}
+
+static int csi_runtime_resume(struct device *dev)
+{
+     struct tegra_csi *csi = dev_get_drvdata(dev);
+     int ret;
+
+     ret = clk_prepare_enable(csi->csi_clk);
+     if (ret) {
+             dev_err(csi->dev, "failed to enable csi clock: %d\n", ret);
+             return ret;
+     }
+
+     /*
+      * Tegra210 TPG internal logic uses PLLD out along with
+      * the CIL clock. So, enable TPG clock.
+      */
+     if (csi->tpg_clk) {
+             ret = clk_set_rate(csi->tpg_clk, TEGRA210_TPG_CLOCK);
+             if (ret)
+                     dev_warn(csi->dev,
+                              "failed to set tpg clock rate: %d\n", ret);
+
+             ret = clk_prepare_enable(csi->tpg_clk);
There's a lot of repetition done for all these clocks. I wonder if using
e.g. clk_bulk_prepare_enable() would help here.

+             if (ret) {
+                     dev_err(csi->dev,
+                             "failed to enable tpg clock: %d\n", ret);
+                     goto disable_csi_clk;
+             }
+     }
+
+     if (csi->cilab_clk) {
+             ret = clk_set_rate(csi->cilab_clk, csi->soc->cil_max_clk_hz);
+             if (ret)
+                     dev_warn(csi->dev,
+                              "failed to set cilab clock rate: %d\n", ret);
+
+             ret = clk_prepare_enable(csi->cilab_clk);
+             if (ret) {
+                     dev_err(csi->dev,
+                             "failed to enable cilab clock: %d\n", ret);
+                     goto disable_tpg_clk;
+             }
+     }
+
+     if (csi->cilcd_clk) {
+             ret = clk_set_rate(csi->cilcd_clk, csi->soc->cil_max_clk_hz);
+             if (ret)
+                     dev_warn(csi->dev,
+                              "failed to set cilcd clock rate: %d\n", ret);
+
+             ret = clk_prepare_enable(csi->cilcd_clk);
+             if (ret) {
+                     dev_err(csi->dev,
+                             "failed to enable cilcd clock: %d\n", ret);
+                     goto disable_cilab_clk;
+             }
+     }
+
+     if (csi->cilef_clk) {
+             ret = clk_set_rate(csi->cilef_clk, csi->soc->cil_max_clk_hz);
+             if (ret)
+                     dev_warn(csi->dev,
+                              "failed to set cilef clock rate: %d\n", ret);
+
+             ret = clk_prepare_enable(csi->cilef_clk);
+             if (ret) {
+                     dev_err(csi->dev,
+                             "failed to enable cilef clock: %d\n", ret);
+                     goto disable_cilcd_clk;
+             }
+     }
+
+     return 0;
+
+disable_cilcd_clk:
+     if (csi->cilcd_clk)
+             clk_disable_unprepare(csi->cilcd_clk);
+disable_cilab_clk:
+     if (csi->cilab_clk)
+             clk_disable_unprepare(csi->cilab_clk);
+disable_tpg_clk:
+     if (csi->tpg_clk)
+             clk_disable_unprepare(csi->tpg_clk);
+disable_csi_clk:
+     clk_disable_unprepare(csi->csi_clk);
+     return ret;
+}
+
+static int csi_runtime_suspend(struct device *dev)
__maybe_unused for this and the above one.

+{
+     struct tegra_csi *csi = dev_get_drvdata(dev);
+
+     clk_disable_unprepare(csi->csi_clk);
+     if (csi->tpg_clk)
+             clk_disable_unprepare(csi->tpg_clk);
+     if (csi->cilab_clk)
+             clk_disable_unprepare(csi->cilab_clk);
+     if (csi->cilcd_clk)
+             clk_disable_unprepare(csi->cilcd_clk);
+     if (csi->cilef_clk)
+             clk_disable_unprepare(csi->cilef_clk);
The clock framework can tolerate NULL just fine, no need for these checks.

+
+     return 0;
+}
+
+static const struct tegra_csi_ops tegra210_csi_ops = {
+     .hw_init = tegra210_csi_hw_init,
+     .csi_streaming = tegra210_csi_streaming,
+     .csi_err_recover = tegra210_csi_error_recover,
+};
+
+static const struct tegra_csi_soc tegra210_csi_soc = {
+     .ops = &tegra210_csi_ops,
+     .cil_max_clk_hz = 102000000,
+     .csi_max_channels = 6,
+};
+
+static const struct of_device_id tegra_csi_of_id_table[] = {
+     { .compatible = "nvidia,tegra210-csi", .data = &tegra210_csi_soc },
+     { }
+};
+MODULE_DEVICE_TABLE(of, tegra_csi_of_id_table);
+
+static const struct dev_pm_ops tegra_csi_pm_ops = {
+     SET_RUNTIME_PM_OPS(csi_runtime_suspend, csi_runtime_resume, NULL)
+};
+
+struct platform_driver tegra_csi_driver = {
+     .driver = {
+             .name           = "tegra-csi",
+             .of_match_table = tegra_csi_of_id_table,
+             .pm             = &tegra_csi_pm_ops,
+     },
+     .probe                  = tegra_csi_probe,
+     .remove                 = tegra_csi_remove,
+};
+
+MODULE_AUTHOR("Sowjanya Komatineni <skomatineni@xxxxxxxxxx>");
+MODULE_DESCRIPTION("NVIDIA Tegra CSI Device Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/staging/media/tegra/tegra-csi.h b/drivers/staging/media/tegra/tegra-csi.h
new file mode 100644
index 0000000..040ecee
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra-csi.h
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#ifndef __TEGRA_CSI_H__
+#define __TEGRA_CSI_H__
+
+#include <media/media-device.h>
+#include <media/media-entity.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-dev.h>
+#include <media/videobuf2-v4l2.h>
+
+/*
+ * Each CSI brick supports max of 4 lanes that can be used as either
+ * one x4 port using both CILA and CILB partitions of a CSI brick or can
+ * be used as two x2 ports with one x2 from CILA and the other x2 from
+ * CILB.
+ */
+#define CSI_PORTS_PER_BRICK  2
+
+/* each CSI channel can have one sink and one source pads */
+#define TEGRA_CSI_PADS_NUM   2
+
+enum tegra_csi_cil_port {
+     PORT_A = 0,
+     PORT_B,
+};
+
+enum tegra_csi_block {
+     CSI_CIL_AB = 0,
+     CSI_CIL_CD,
+     CSI_CIL_EF,
+};
+
+struct tegra_csi;
+
+struct tegra_csi_channel {
+     struct list_head list;
+     struct v4l2_subdev subdev;
+     struct media_pad pads[TEGRA_CSI_PADS_NUM];
+     struct device_node *of_node;
+     struct tegra_csi *csi;
+     unsigned int numlanes;
+     unsigned int numpads;
+     u8 csi_port_num;
+
+     /* one pair of sink/source pad has one format */
+     struct v4l2_mbus_framefmt format;
+};
+
+/**
+ * struct tegra_csi_ops - Tegra CSI operations
+ * @hw_init: gets the tegra csi and cil clocks.
+ * @csi_streaming: programs csi hardware to enable or disable streaming.
+ * @csi_err_recover: csi hardware block recovery in case of any capture errors
+ *           due to missing source stream or due to improper csi input from
+ *           the external source.
+ */
+struct tegra_csi_ops {
+     int (*hw_init)(struct tegra_csi *csi);
+     int (*csi_streaming)(struct tegra_csi_channel *csi_chan, u8 pg_mode,
+                          int enable);
+     void (*csi_err_recover)(struct tegra_csi_channel *csi_chan);
+};
+
+/**
+ * struct tegra_csi_soc - NVIDIA Tegra CSI SoC structure
+ * @ops: csi hardware operations
+ * @cil_max_clk_hz: cil clock max frequency
+ * @csi_max_channels: supported max streaming channels
+ */
+struct tegra_csi_soc {
+     const struct tegra_csi_ops *ops;
+     unsigned int cil_max_clk_hz;
+     unsigned int csi_max_channels;
+};
+
+/**
+ * struct tegra_csi - NVIDIA Tegra CSI device structure
+ *
+ * @dev: device struct
+ * @client: host1x_client struct
+ * @iomem: register base
+ * @csi_clk: clock for CSI
+ * @cilab_clk: clock for CIL AB
+ * @cilcd_clk: clock for CIL CD
+ * @cilef_clk: clock for CIL EF
+ * @tpg_clk: clock for internal CSI TPG logic
+ * @soc: pointer to SoC data structure
+ * @ops: csi operations
+ * @channels: list head for CSI channels
+ */
+struct tegra_csi {
+     struct device *dev;
+     struct host1x_client client;
+     void __iomem *iomem;
+     struct clk *csi_clk;
+     struct clk *cilab_clk;
+     struct clk *cilcd_clk;
+     struct clk *cilef_clk;
+     struct clk *tpg_clk;
+     const struct tegra_csi_soc *soc;
+     const struct tegra_csi_ops *ops;
+     struct list_head csi_chans;
+};
+
+void tegra_csi_error_recover(struct v4l2_subdev *subdev);
+
+void tegra210_csi_error_recover(struct tegra_csi_channel *csi_chan);
+int tegra210_csi_streaming(struct tegra_csi_channel *csi_chan, u8 pg_mode,
+                        int enable);
+int tegra210_csi_hw_init(struct tegra_csi *csi);
+
+#endif
diff --git a/drivers/staging/media/tegra/tegra-vi.c b/drivers/staging/media/tegra/tegra-vi.c
new file mode 100644
index 0000000..9714152
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra-vi.c
@@ -0,0 +1,1058 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/host1x.h>
+#include <linux/kthread.h>
+#include <linux/lcm.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-fh.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-dma-contig.h>
+
+#include <soc/tegra/pmc.h>
+
+#include "tegra-video.h"
+#include "tegra-common.h"
+#include "tegra-vi.h"
+
+#define SURFACE_ALIGN_BYTES          64
+#define MAX_CID_CONTROLS             1
+
+static const struct tegra_video_format tegra_default_format = {
+     .img_dt = TEGRA_IMAGE_DT_RAW10,
+     .bit_width = 10,
+     .code = MEDIA_BUS_FMT_SRGGB10_1X10,
+     .bpp = 2,
+     .img_fmt = TEGRA_IMAGE_FORMAT_DEF,
+     .fourcc = V4L2_PIX_FMT_SRGGB10,
+};
+
+static inline struct tegra_vi *
+host1x_client_to_vi(struct host1x_client *client)
+{
+     return container_of(client, struct tegra_vi, client);
+}
+
+static inline struct tegra_channel_buffer *
+to_tegra_channel_buffer(struct vb2_v4l2_buffer *vb)
+{
+     return container_of(vb, struct tegra_channel_buffer, buf);
+}
+
+static int tegra_get_format_idx_by_code(struct tegra_vi *vi,
+                                     unsigned int code)
+{
+     unsigned int i;
+
+     for (i = 0; i < vi->soc->nformats; ++i) {
+             if (vi->soc->video_formats[i].code == code)
+                     return i;
+     }
+
+     return -1;
+}
+
+static u32 tegra_get_format_fourcc_by_idx(struct tegra_vi *vi,
+                                       unsigned int index)
+{
+     if (index >= vi->soc->nformats)
+             return -EINVAL;
+
+     return vi->soc->video_formats[index].fourcc;
+}
+
+static const struct tegra_video_format *
+tegra_get_format_by_fourcc(struct tegra_vi *vi, u32 fourcc)
+{
+     unsigned int i;
+
+     for (i = 0; i < vi->soc->nformats; ++i) {
+             if (vi->soc->video_formats[i].fourcc == fourcc)
+                     return &vi->soc->video_formats[i];
+     }
+
+     return NULL;
+}
+
+/*
+ * videobuf2 queue operations
+ */
+static int tegra_channel_queue_setup(struct vb2_queue *vq,
+                                  unsigned int *nbuffers,
+                                  unsigned int *nplanes,
+                                  unsigned int sizes[],
+                                  struct device *alloc_devs[])
+{
+     struct tegra_vi_channel *chan = vb2_get_drv_priv(vq);
+
+     if (*nplanes)
+             return sizes[0] < chan->format.sizeimage ? -EINVAL : 0;
+
+     *nplanes = 1;
+     sizes[0] = chan->format.sizeimage;
+     alloc_devs[0] = chan->vi->dev;
+
+     return 0;
+}
+
+static int tegra_channel_buffer_prepare(struct vb2_buffer *vb)
+{
+     struct tegra_vi_channel *chan = vb2_get_drv_priv(vb->vb2_queue);
+     struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+     struct tegra_channel_buffer *buf = to_tegra_channel_buffer(vbuf);
+     unsigned long size = chan->format.sizeimage;
+
+     if (vb2_plane_size(vb, 0) < size) {
+             v4l2_err(chan->video->v4l2_dev,
+                      "buffer too small (%lu < %lu)\n",
+                      vb2_plane_size(vb, 0), size);
+             return -EINVAL;
+     }
+
+     vb2_set_plane_payload(vb, 0, size);
+     buf->chan = chan;
+     buf->addr = vb2_dma_contig_plane_dma_addr(vb, 0);
+
+     return 0;
+}
+
+static void tegra_channel_buffer_queue(struct vb2_buffer *vb)
+{
+     struct tegra_vi_channel *chan = vb2_get_drv_priv(vb->vb2_queue);
+     struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+     struct tegra_channel_buffer *buf = to_tegra_channel_buffer(vbuf);
+
+     /* put buffer into the capture queue */
+     spin_lock(&chan->start_lock);
+     list_add_tail(&buf->queue, &chan->capture);
+     spin_unlock(&chan->start_lock);
+
+     /* wait up kthread for capture */
+     wake_up_interruptible(&chan->start_wait);
+}
+
+static struct v4l2_subdev *
+tegra_channel_get_remote_subdev(struct tegra_vi_channel *chan)
+{
+     struct media_pad *pad;
+     struct v4l2_subdev *subdev;
+     struct media_entity *entity;
+
+     pad = media_entity_remote_pad(&chan->pad);
+     entity = pad->entity;
+     subdev = media_entity_to_v4l2_subdev(entity);
+
+     return subdev;
+}
+
+int tegra_channel_csi_error_recover(struct tegra_vi_channel *chan)
+{
+     struct v4l2_subdev *subdev;
+
+     subdev = tegra_channel_get_remote_subdev(chan);
+     tegra_csi_error_recover(subdev);
+     return 0;
+}
+
+int tegra_channel_set_stream(struct tegra_vi_channel *chan, bool on)
+{
+     struct v4l2_subdev *subdev;
+     int ret;
+
+     /* stream CSI */
+     subdev = tegra_channel_get_remote_subdev(chan);
+     v4l2_set_subdev_hostdata(subdev, chan);
+     ret = v4l2_subdev_call(subdev, video, s_stream, on);
+     if (on && ret < 0 && ret != -ENOIOCTLCMD)
+             return ret;
+
+     return 0;
+}
+
+void tegra_channel_release_buffers(struct tegra_vi_channel *chan,
+                                enum vb2_buffer_state state)
+{
+     struct tegra_channel_buffer *buf, *nbuf;
+
+     spin_lock(&chan->start_lock);
+     list_for_each_entry_safe(buf, nbuf, &chan->capture, queue) {
+             vb2_buffer_done(&buf->buf.vb2_buf, state);
+             list_del(&buf->queue);
+     }
+
+     spin_unlock(&chan->start_lock);
+
+     spin_lock(&chan->done_lock);
+     list_for_each_entry_safe(buf, nbuf, &chan->done, queue) {
+             vb2_buffer_done(&buf->buf.vb2_buf, state);
+             list_del(&buf->queue);
+     }
+
+     spin_unlock(&chan->done_lock);
+}
+
+static int tegra_channel_start_streaming(struct vb2_queue *vq, u32 count)
+{
+     struct tegra_vi_channel *chan = vb2_get_drv_priv(vq);
+
+     return chan->vi->ops->vi_start_streaming(vq, count);
+}
+
+static void tegra_channel_stop_streaming(struct vb2_queue *vq)
+{
+     struct tegra_vi_channel *chan = vb2_get_drv_priv(vq);
+
+     chan->vi->ops->vi_stop_streaming(vq);
+}
+
+static const struct vb2_ops tegra_channel_queue_qops = {
+     .queue_setup = tegra_channel_queue_setup,
+     .buf_prepare = tegra_channel_buffer_prepare,
+     .buf_queue = tegra_channel_buffer_queue,
+     .wait_prepare = vb2_ops_wait_prepare,
+     .wait_finish = vb2_ops_wait_finish,
+     .start_streaming = tegra_channel_start_streaming,
+     .stop_streaming = tegra_channel_stop_streaming,
+};
+
+/*
+ * V4L2 ioctls
+ */
+static int tegra_channel_querycap(struct file *file, void *fh,
+                               struct v4l2_capability *cap)
+{
+     struct tegra_vi_channel *chan = video_drvdata(file);
+
+     strscpy(cap->driver, "tegra-video", sizeof(cap->driver));
+     strscpy(cap->card, chan->video->name, sizeof(cap->card));
+     snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
+              dev_name(chan->vi->dev));
+
+     return 0;
+}
+
+static int tegra_channel_enum_format(struct file *file, void *fh,
+                                  struct v4l2_fmtdesc *f)
+{
+     struct tegra_vi_channel *chan = video_drvdata(file);
+     unsigned int index = 0, i;
+     unsigned long *fmts_bitmap = chan->tpg_fmts_bitmap;
+
+     if (f->index >= bitmap_weight(fmts_bitmap, MAX_FORMAT_NUM))
+             return -EINVAL;
+
+     for (i = 0; i < f->index + 1; i++, index++)
+             index = find_next_bit(fmts_bitmap, MAX_FORMAT_NUM, index);
+
+     f->pixelformat = tegra_get_format_fourcc_by_idx(chan->vi, index - 1);
+
+     return 0;
+}
+
+static int tegra_channel_get_format(struct file *file, void *fh,
+                                 struct v4l2_format *format)
+{
+     struct tegra_vi_channel *chan = video_drvdata(file);
+
+     format->fmt.pix = chan->format;
+     return 0;
+}
+
+static void tegra_channel_fmt_align(struct tegra_vi_channel *chan,
+                                 struct v4l2_pix_format *pix,
+                                 unsigned int bpp)
+{
+     unsigned int align;
+     unsigned int min_width;
+     unsigned int max_width;
+     unsigned int width;
+     unsigned int min_bpl;
+     unsigned int max_bpl;
+     unsigned int bpl;
+
+     /*
+      * The transfer alignment requirements are expressed in bytes. Compute
+      * minimum and maximum values, clamp the requested width and convert
+      * it back to pixels. Use bytesperline to adjust the width.
+      */
+     align = lcm(SURFACE_ALIGN_BYTES, bpp);
+     min_width = roundup(TEGRA_MIN_WIDTH, align);
+     max_width = rounddown(TEGRA_MAX_WIDTH, align);
+     width = roundup(pix->width * bpp, align);
+
+     pix->width = clamp(width, min_width, max_width) / bpp;
+     pix->height = clamp(pix->height, TEGRA_MIN_HEIGHT, TEGRA_MAX_HEIGHT);
+
+     /* Clamp the requested bytes per line value. If the maximum bytes per
+      * line value is zero, the module doesn't support user configurable
+      * line sizes. Override the requested value with the minimum in that
+      * case.
+      */
+     min_bpl = pix->width * bpp;
+     max_bpl = rounddown(TEGRA_MAX_WIDTH, SURFACE_ALIGN_BYTES);
+     bpl = roundup(pix->bytesperline, SURFACE_ALIGN_BYTES);
+
+     pix->bytesperline = clamp(bpl, min_bpl, max_bpl);
+     pix->sizeimage = pix->bytesperline * pix->height;
+}
+
+static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
+                                   struct v4l2_pix_format *pix)
+{
+     const struct tegra_video_format *fmtinfo;
+     struct v4l2_subdev *subdev;
+     struct v4l2_subdev_format fmt;
+     struct v4l2_subdev_pad_config *pad_cfg;
+
+     subdev = tegra_channel_get_remote_subdev(chan);
+     pad_cfg = v4l2_subdev_alloc_pad_config(subdev);
+     if (!pad_cfg)
+             return -ENOMEM;
+     /*
+      * Retrieve the format information and if requested format isn't
+      * supported, keep the current format.
+      */
+     fmtinfo = tegra_get_format_by_fourcc(chan->vi, pix->pixelformat);
+     if (!fmtinfo) {
+             pix->pixelformat = chan->format.pixelformat;
+             pix->colorspace = chan->format.colorspace;
+             fmtinfo = tegra_get_format_by_fourcc(chan->vi,
+                                                  pix->pixelformat);
+     }
+
+     pix->field = V4L2_FIELD_NONE;
+     fmt.which = V4L2_SUBDEV_FORMAT_TRY;
+     fmt.pad = 0;
+     v4l2_fill_mbus_format(&fmt.format, pix, fmtinfo->code);
+     v4l2_subdev_call(subdev, pad, set_fmt, pad_cfg, &fmt);
+     v4l2_fill_pix_format(pix, &fmt.format);
+     tegra_channel_fmt_align(chan, pix, fmtinfo->bpp);
+
+     v4l2_subdev_free_pad_config(pad_cfg);
+
+     return 0;
+}
+
+static int tegra_channel_try_format(struct file *file, void *fh,
+                                 struct v4l2_format *format)
+{
+     struct tegra_vi_channel *chan = video_drvdata(file);
+
+     return __tegra_channel_try_format(chan, &format->fmt.pix);
+}
+
+static int tegra_channel_set_format(struct file *file, void *fh,
+                                 struct v4l2_format *format)
+{
+     struct tegra_vi_channel *chan = video_drvdata(file);
+     const struct tegra_video_format *fmtinfo;
+     struct v4l2_subdev_format fmt;
+     struct v4l2_subdev *subdev;
+     struct v4l2_pix_format *pix = &format->fmt.pix;
+     int ret;
+
+     if (vb2_is_busy(&chan->queue))
+             return -EBUSY;
+
+     /* get supported format by try_fmt */
+     ret = __tegra_channel_try_format(chan, pix);
+     if (ret)
+             return ret;
+
+     fmtinfo = tegra_get_format_by_fourcc(chan->vi, pix->pixelformat);
+
+     fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
+     fmt.pad = 0;
+     v4l2_fill_mbus_format(&fmt.format, pix, fmtinfo->code);
+     subdev = tegra_channel_get_remote_subdev(chan);
+     v4l2_subdev_call(subdev, pad, set_fmt, NULL, &fmt);
+     v4l2_fill_pix_format(pix, &fmt.format);
+     tegra_channel_fmt_align(chan, pix, fmtinfo->bpp);
+
+     chan->format = *pix;
+     chan->fmtinfo = fmtinfo;
+
+     return 0;
+}
+
+static int tegra_channel_enum_input(struct file *file, void *fh,
+                                 struct v4l2_input *inp)
+{
+     /* currently driver supports internal TPG only */
+     if (inp->index)
+             return -EINVAL;
+
+     inp->type = V4L2_INPUT_TYPE_CAMERA;
+     strscpy(inp->name, "Tegra TPG", sizeof(inp->name));
+
+     return 0;
+}
+
+static int tegra_channel_g_input(struct file *file, void *priv,
+                              unsigned int *i)
+{
+     *i = 0;
+     return 0;
+}
+
+static int tegra_channel_s_input(struct file *file, void *priv,
+                              unsigned int input)
+{
+     if (input > 0)
+             return -EINVAL;
+
+     return 0;
+}
Please see patchset on topic "v4l2-dev/ioctl: Add V4L2_CAP_IO_MC" on
linux-media; it's relevant here, too.

+
+static const struct v4l2_ioctl_ops tegra_channel_ioctl_ops = {
+     .vidioc_querycap                = tegra_channel_querycap,
+     .vidioc_enum_fmt_vid_cap        = tegra_channel_enum_format,
+     .vidioc_g_fmt_vid_cap           = tegra_channel_get_format,
+     .vidioc_s_fmt_vid_cap           = tegra_channel_set_format,
+     .vidioc_try_fmt_vid_cap         = tegra_channel_try_format,
+     .vidioc_enum_input              = tegra_channel_enum_input,
+     .vidioc_g_input                 = tegra_channel_g_input,
+     .vidioc_s_input                 = tegra_channel_s_input,
+     .vidioc_reqbufs                 = vb2_ioctl_reqbufs,
+     .vidioc_prepare_buf             = vb2_ioctl_prepare_buf,
+     .vidioc_querybuf                = vb2_ioctl_querybuf,
+     .vidioc_qbuf                    = vb2_ioctl_qbuf,
+     .vidioc_dqbuf                   = vb2_ioctl_dqbuf,
+     .vidioc_create_bufs             = vb2_ioctl_create_bufs,
+     .vidioc_expbuf                  = vb2_ioctl_expbuf,
+     .vidioc_streamon                = vb2_ioctl_streamon,
+     .vidioc_streamoff               = vb2_ioctl_streamoff,
+     .vidioc_subscribe_event         = v4l2_ctrl_subscribe_event,
+     .vidioc_unsubscribe_event       = v4l2_event_unsubscribe,
+};
+
+/*
+ * V4L2 file operations
+ */
+static const struct v4l2_file_operations tegra_channel_fops = {
+     .owner          = THIS_MODULE,
+     .unlocked_ioctl = video_ioctl2,
+     .open           = v4l2_fh_open,
+     .release        = vb2_fop_release,
+     .read           = vb2_fop_read,
+     .poll           = vb2_fop_poll,
+     .mmap           = vb2_fop_mmap,
+};
+
+static const char *const vi_pattern_strings[] = {
+     "Black/White Direct Mode",
+     "Color Patch Mode",
+};
+
+static int vi_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+     struct tegra_vi_channel *chan = container_of(ctrl->handler,
+                                                  struct tegra_vi_channel,
+                                                  ctrl_handler);
+
+     switch (ctrl->id) {
+     case V4L2_CID_TEST_PATTERN:
+             /* pattern change takes effect on next stream */
+             chan->pg_mode = ctrl->val + 1;
+             break;
+     default:
+             return -EINVAL;
+     }
+
+     return 0;
+}
+
+static const struct v4l2_ctrl_ops vi_ctrl_ops = {
+     .s_ctrl = vi_s_ctrl,
+};
+
+int tegra_channel_setup_ctrl_handler(struct tegra_vi_channel *chan)
+{
+     int ret;
+
+     /* add test pattern control handler to v4l2 device */
+     v4l2_ctrl_new_std_menu_items(&chan->ctrl_handler, &vi_ctrl_ops,
+                                  V4L2_CID_TEST_PATTERN,
+                                  ARRAY_SIZE(vi_pattern_strings) - 1,
+                                  0, 0, vi_pattern_strings);
+     if (chan->ctrl_handler.error) {
+             dev_err(chan->vi->dev, "failed to add TPG ctrl handler: %d\n",
+                     chan->ctrl_handler.error);
+             v4l2_ctrl_handler_free(&chan->ctrl_handler);
+             return chan->ctrl_handler.error;
+     }
+
+     /* setup the controls */
+     ret = v4l2_ctrl_handler_setup(&chan->ctrl_handler);
+     if (ret < 0) {
+             dev_err(chan->vi->dev,
+                     "failed to setup v4l2 ctrl handler: %d\n", ret);
+             goto free_hdl;
+     }
+
+     return 0;
+
+free_hdl:
+     v4l2_ctrl_handler_free(&chan->ctrl_handler);
+     return ret;
+}
+
+/* VI only support 2 formats in TPG mode */
+static void vi_tpg_fmts_bitmap_init(struct tegra_vi_channel *chan)
+{
+     int index;
+
+     bitmap_zero(chan->tpg_fmts_bitmap, MAX_FORMAT_NUM);
+
+     index = tegra_get_format_idx_by_code(chan->vi,
+                                          MEDIA_BUS_FMT_SRGGB10_1X10);
+     bitmap_set(chan->tpg_fmts_bitmap, index, 1);
+
+     index = tegra_get_format_idx_by_code(chan->vi,
+                                          MEDIA_BUS_FMT_RGB888_1X32_PADHI);
+     bitmap_set(chan->tpg_fmts_bitmap, index, 1);
+}
+
+static int tegra_channel_init(struct tegra_vi_channel *chan)
+{
+     struct tegra_vi *vi = chan->vi;
+     struct tegra_video_device *vid = dev_get_drvdata(vi->client.host);
+     unsigned long flags = HOST1X_SYNCPT_CLIENT_MANAGED;
+     int ret;
+
+     mutex_init(&chan->video_lock);
Also remember mutex_destroy().

+     INIT_LIST_HEAD(&chan->capture);
+     INIT_LIST_HEAD(&chan->done);
+     spin_lock_init(&chan->start_lock);
+     spin_lock_init(&chan->done_lock);
+     init_waitqueue_head(&chan->start_wait);
+     init_waitqueue_head(&chan->done_wait);
+
+     /* initialize the video format */
+     chan->fmtinfo = &tegra_default_format;
+     chan->format.pixelformat = chan->fmtinfo->fourcc;
+     chan->format.colorspace = V4L2_COLORSPACE_SRGB;
+     chan->format.field = V4L2_FIELD_NONE;
+     chan->format.width = TEGRA_DEF_WIDTH;
+     chan->format.height = TEGRA_DEF_HEIGHT;
+     chan->format.bytesperline = TEGRA_DEF_WIDTH * chan->fmtinfo->bpp;
+     chan->format.sizeimage = chan->format.bytesperline * TEGRA_DEF_HEIGHT;
+     tegra_channel_fmt_align(chan, &chan->format, chan->fmtinfo->bpp);
+
+     chan->video = video_device_alloc();
No need to allocate separately; put this into e.g. struct tegra_vi_channel.

+     if (!chan->video) {
+             dev_err(vi->dev, "unable to allocate video device\n");
+             return -ENOMEM;
+     }
+
+     /* initialize the media entity */
+     chan->pad.flags = MEDIA_PAD_FL_SINK;
+     ret = media_entity_pads_init(&chan->video->entity, 1, &chan->pad);
+     if (ret < 0) {
+             dev_err(vi->dev,
+                     "failed to initialize media entity: %d\n", ret);
+             goto release_vdev;
+     }
+
+     ret = v4l2_ctrl_handler_init(&chan->ctrl_handler, MAX_CID_CONTROLS);
+     if (chan->ctrl_handler.error) {
+             dev_err(vi->dev,
+                     "failed to initialize v4l2 ctrl handler: %d\n", ret);
+             goto cleanup_media;
+     }
+
+     /* initialize the video_device */
+     chan->video->fops = &tegra_channel_fops;
+     chan->video->v4l2_dev = &vid->v4l2_dev;
+     chan->video->release = video_device_release_empty;
+     chan->video->queue = &chan->queue;
+     snprintf(chan->video->name, sizeof(chan->video->name), "%s-%s-%u",
+              dev_name(vi->dev), "output", chan->portno);
+     chan->video->vfl_type = VFL_TYPE_VIDEO;
+     chan->video->vfl_dir = VFL_DIR_RX;
+     chan->video->ioctl_ops = &tegra_channel_ioctl_ops;
+     chan->video->ctrl_handler = &chan->ctrl_handler;
+     chan->video->lock = &chan->video_lock;
+     chan->video->device_caps = V4L2_CAP_VIDEO_CAPTURE |
+                                V4L2_CAP_STREAMING |
+                                V4L2_CAP_READWRITE;
+     video_set_drvdata(chan->video, chan);
+
+     chan->frame_start_sp = host1x_syncpt_request(&vi->client, flags);
+     if (!chan->frame_start_sp) {
+             dev_err(vi->dev, "failed to request frame start syncpoint\n");
+             ret = -ENOMEM;
+             goto free_v4l2_ctrl_hdl;
+     }
+
+     chan->mw_ack_sp = host1x_syncpt_request(&vi->client, flags);
+     if (!chan->mw_ack_sp) {
+             dev_err(vi->dev, "failed to request memory ack syncpoint\n");
+             ret = -ENOMEM;
+             goto free_fs_syncpt;
+     }
+
+     chan->queue.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+     chan->queue.io_modes = VB2_MMAP | VB2_DMABUF | VB2_READ;
+     chan->queue.lock = &chan->video_lock;
+     chan->queue.drv_priv = chan;
+     chan->queue.buf_struct_size = sizeof(struct tegra_channel_buffer);
+     chan->queue.ops = &tegra_channel_queue_qops;
+     chan->queue.min_buffers_needed = 3;
+     chan->queue.mem_ops = &vb2_dma_contig_memops;
+     chan->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+     chan->queue.dev = vi->dev;
+     ret = vb2_queue_init(&chan->queue);
+     if (ret < 0) {
+             dev_err(vi->dev, "failed to initialize vb2 queue: %d\n", ret);
+             goto free_mw_ack_syncpt;
+     }
+
+     ret = video_register_device(chan->video, VFL_TYPE_VIDEO, -1);
+     if (ret < 0) {
+             dev_err(vi->dev, "failed to register video device: %d\n", ret);
+             goto rel_vb2_queue;
+     }
+
+     return 0;
+
+rel_vb2_queue:
+     vb2_queue_release(&chan->queue);
+free_mw_ack_syncpt:
+     host1x_syncpt_free(chan->mw_ack_sp);
+free_fs_syncpt:
+     host1x_syncpt_free(chan->frame_start_sp);
+free_v4l2_ctrl_hdl:
+     v4l2_ctrl_handler_free(&chan->ctrl_handler);
+cleanup_media:
+     media_entity_cleanup(&chan->video->entity);
+release_vdev:
+     video_device_release(chan->video);
+     return ret;
+}
+
+static int tegra_vi_tpg_channels_alloc(struct tegra_vi *vi)
+{
+     struct tegra_vi_channel *chan, *tmp;
+     unsigned int port_num;
+     unsigned int nchannels = vi->soc->vi_max_channels;
+     int ret = 0;
+
+     for (port_num = 0; port_num < nchannels; port_num++) {
+             chan = kzalloc(sizeof(*chan), GFP_KERNEL);
+             if (!chan) {
+                     ret = -ENOMEM;
+                     goto cleanup;
+             }
+
+             chan->vi = vi;
+             chan->portno = port_num;
+             list_add_tail(&chan->list, &vi->vi_chans);
+     }
+
+     return 0;
+
+cleanup:
+     list_for_each_entry_safe(chan, tmp, &vi->vi_chans, list) {
+             list_del(&chan->list);
+             kfree(chan);
+     }
+
+     return ret;
+}
+
+static int tegra_vi_channels_init(struct tegra_vi *vi)
+{
+     struct tegra_vi_channel *chan;
+     int ret;
+
+     list_for_each_entry(chan, &vi->vi_chans, list) {
+             ret = tegra_channel_init(chan);
+             if (ret < 0) {
+                     dev_err(vi->dev, "channel %d init failed: %d\n",
+                             chan->portno, ret);
+                     return ret;
+             }
+     }
+
+     return 0;
+}
+
+static void tegra_vi_channels_cleanup(struct tegra_vi *vi)
+{
+     struct tegra_vi_channel *chan, *tmp;
+
+     list_for_each_entry_safe(chan, tmp, &vi->vi_chans, list) {
+             if (chan->video) {
+                     video_unregister_device(chan->video);
+                     mutex_lock(&chan->video_lock);
+                     vb2_queue_release(&chan->queue);
+                     mutex_unlock(&chan->video_lock);
+                     video_device_release(chan->video);
+             }
+
+             if (chan->frame_start_sp)
+                     host1x_syncpt_free(chan->frame_start_sp);
+
+             if (chan->mw_ack_sp)
+                     host1x_syncpt_free(chan->mw_ack_sp);
+
+             v4l2_ctrl_handler_free(&chan->ctrl_handler);
+
+             list_del(&chan->list);
+             kfree(chan);
+     }
+}
+
+static int tegra_vi_tpg_graph_init(struct tegra_vi *vi)
+{
+     struct tegra_video_device *vid = dev_get_drvdata(vi->client.host);
+     struct tegra_csi *csi = vid->csi;
+     struct tegra_vi_channel *vi_chan;
+     struct tegra_csi_channel *csi_chan;
+     u32 link_flags = MEDIA_LNK_FL_ENABLED;
+     int ret = 0;
+
+     csi_chan = list_first_entry(&csi->csi_chans, struct tegra_csi_channel,
+                                 list);
+
+     list_for_each_entry(vi_chan, &vi->vi_chans, list) {
+             struct media_entity *source = &csi_chan->subdev.entity;
+             struct media_entity *sink = &vi_chan->video->entity;
+             struct media_pad *source_pad = csi_chan->pads;
+             struct media_pad *sink_pad = &vi_chan->pad;
+
+             ret = v4l2_device_register_subdev(&vid->v4l2_dev,
+                                               &csi_chan->subdev);
Please first create the links, then register the subdev.

Where is the corresponding media entity initialised?
video entity is initialized in channel_init for all channels and subdevice entity initialization happens in CSI driver.

+             if (ret) {
+                     dev_err(vi->dev,
+                             "failed to register subdev: %d\n", ret);
+                     return ret;
+             }
+
+             dev_dbg(vi->dev, "creating %s:%u -> %s:%u link\n",
+                     source->name, source_pad->index,
+                     sink->name, sink_pad->index);
+
+             ret = media_create_pad_link(source, source_pad->index,
+                                         sink, sink_pad->index,
+                                         link_flags);
+             if (ret < 0) {
+                     dev_err(vi->dev,
+                             "failed to create %s:%u -> %s:%u link: %d\n",
+                             source->name, source_pad->index,
+                             sink->name, sink_pad->index, ret);
+                     return ret;
+             }
+
+             vi_tpg_fmts_bitmap_init(vi_chan);
+             tegra_channel_setup_ctrl_handler(vi_chan);
+             csi_chan = list_next_entry(csi_chan, list);
+     }
+
+     return 0;
+}
+
+static void tegra_vi_tpg_graph_cleanup(struct tegra_vi *vi)
+{
+     struct tegra_video_device *vid = dev_get_drvdata(vi->client.host);
+     struct tegra_csi *csi = vid->csi;
+     struct tegra_csi_channel *csi_chan;
+
+     list_for_each_entry(csi_chan, &csi->csi_chans, list)
+             v4l2_device_unregister_subdev(&csi_chan->subdev);
+}
+
+static int tegra_vi_init(struct host1x_client *client)
+{
+     struct tegra_video_device *vid = dev_get_drvdata(client->host);
+     struct tegra_vi *vi = host1x_client_to_vi(client);
+     int ret;
+
+     vid->vi = vi;
+     vid->media_dev.hw_revision = vi->soc->hw_revision;
+     snprintf(vid->media_dev.bus_info, sizeof(vid->media_dev.bus_info),
+              "platform:%s", dev_name(vi->dev));
+
+     if (!vid->csi) {
+             dev_err(vi->dev, "csi host1x client is not initialized\n");
+             return -ENODEV;
+     }
+
+     INIT_LIST_HEAD(&vi->vi_chans);
+
+     ret = tegra_vi_tpg_channels_alloc(vi);
+     if (ret < 0)
+             return ret;
+
+     ret = tegra_vi_channels_init(vi);
+     if (ret < 0)
+             goto cleanup;
+
+     ret = pm_runtime_get_sync(vi->dev);
+     if (ret < 0) {
+             dev_err(vi->dev, "runtime resume failed: %d\n", ret);
+             goto cleanup;
s/cleanup/rpm_put/

+     }
+
+     /* setup media links between Tegra VI and CSI for TPG */
+     ret = tegra_vi_tpg_graph_init(vi);
+     if (ret < 0)
+             goto rpm_put;
+
+     return 0;
+
+rpm_put:
+     pm_runtime_put_sync(vi->dev);
+cleanup:
+     tegra_vi_channels_cleanup(vi);
+     return ret;
+}
+
+static int tegra_vi_exit(struct host1x_client *client)
+{
+     struct tegra_video_device *vid = dev_get_drvdata(client->host);
+     struct tegra_vi *vi = vid->vi;
+
+     if (!vid->vi)
+             return 0;
+
+     tegra_vi_channels_cleanup(vi);
+     tegra_vi_tpg_graph_cleanup(vi);
+     pm_runtime_put_sync(vi->dev);
+
+     return 0;
+}
+
+static const struct host1x_client_ops vi_client_ops = {
+     .init = tegra_vi_init,
+     .exit = tegra_vi_exit,
+};
+
+static int tegra_vi_probe(struct platform_device *pdev)
+{
+     struct resource *res;
+     struct tegra_vi *vi;
+     int ret;
+
+     vi = kzalloc(sizeof(*vi), GFP_KERNEL);
You could use devm_kzalloc(), and not worry about freeing it.
switched from devm_kzalloc to kzalloc based on earlier feedback to make sure of no crash during unbind as memory allocated with device managed resource gets immediately freed.

+     if (!vi)
+             return -ENOMEM;
+
+     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+     vi->iomem = devm_ioremap_resource(&pdev->dev, res);
+     if (IS_ERR(vi->iomem)) {
+             ret = PTR_ERR(vi->iomem);
+             goto cleanup;
+     }
+
+     vi->soc = of_device_get_match_data(&pdev->dev);
+     if (!vi->soc) {
+             ret = -ENODATA;
+             goto cleanup;
+     }
+
+     vi->vi_clk = devm_clk_get(&pdev->dev, "vi");
+     if (IS_ERR(vi->vi_clk)) {
+             ret = PTR_ERR(vi->vi_clk);
+             dev_err(&pdev->dev, "failed to get vi clock: %d\n", ret);
+             goto cleanup;
+     }
+
+     vi->vi_reg = devm_regulator_get(&pdev->dev, "avdd-dsi-csi");
+     if (IS_ERR(vi->vi_reg)) {
+             ret = PTR_ERR(vi->vi_reg);
+             dev_err(&pdev->dev, "failed to get VDD supply: %d\n", ret);
+             goto cleanup;
+     }
+
+     if (!pdev->dev.pm_domain) {
+             ret = -ENOENT;
+             dev_warn(&pdev->dev, "PM domain is not attached: %d\n", ret);
+             goto cleanup;
+     }
+
+     ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
+     if (ret) {
+             dev_err(&pdev->dev,
+                     "failed to populate vi child device: %d\n", ret);
+             goto cleanup;
+     }
+
+     vi->dev = &pdev->dev;
+     vi->ops = vi->soc->ops;
+     platform_set_drvdata(pdev, vi);
+     pm_runtime_enable(&pdev->dev);
+
+     /* initialize host1x interface */
+     INIT_LIST_HEAD(&vi->client.list);
+     vi->client.ops = &vi_client_ops;
+     vi->client.dev = &pdev->dev;
+
+     ret = host1x_client_register(&vi->client);
+     if (ret < 0) {
+             dev_err(vi->dev,
+                     "failed to register host1x client: %d\n", ret);
+             ret = -ENODEV;
+             goto rpm_disable;
+     }
+
+     return 0;
+
+rpm_disable:
+     pm_runtime_disable(&pdev->dev);
+     of_platform_depopulate(vi->dev);
+cleanup:
+     kfree(vi);
+     return ret;
+}
+
+static int tegra_vi_remove(struct platform_device *pdev)
+{
+     struct tegra_vi *vi = platform_get_drvdata(pdev);
+     int err;
+
+     pm_runtime_disable(vi->dev);
Does this driver work without runtime PM (CONFIG_PM nowadays)?
Missed CONFIG_PM check. Will add.

+
+     err = host1x_client_unregister(&vi->client);
+     if (err < 0) {
+             dev_err(vi->dev,
+                     "failed to unregister host1x client: %d\n", err);
+             return err;
+     }
+
+     of_platform_depopulate(vi->dev);
+     kfree(vi);
+
+     return 0;
+}
+
+static int vi_runtime_resume(struct device *dev)
+{
+     struct tegra_vi *vi = dev_get_drvdata(dev);
+     int ret;
+
+     ret = regulator_enable(vi->vi_reg);
+     if (ret) {
+             dev_err(dev, "failed to enable VDD supply: %d\n", ret);
+             return ret;
+     }
+
+     ret = clk_set_rate(vi->vi_clk, vi->soc->vi_max_clk_hz);
+     if (ret) {
+             dev_err(dev, "failed to set vi clock rate: %d\n", ret);
+             goto disable_vi_reg;
+     }
+
+     ret = clk_prepare_enable(vi->vi_clk);
+     if (ret) {
+             dev_err(dev, "failed to enable vi clock: %d\n", ret);
+             goto disable_vi_reg;
+     }
+
+     return 0;
+
+disable_vi_reg:
+     regulator_disable(vi->vi_reg);
+     return ret;
+}
+
+static int vi_runtime_suspend(struct device *dev)
+{
+     struct tegra_vi *vi = dev_get_drvdata(dev);
+
+     clk_disable_unprepare(vi->vi_clk);
+     regulator_disable(vi->vi_reg);
+
+     return 0;
+}
+
+/* Tegra supported video formats */
+const struct tegra_video_format tegra210_video_formats[] = {
+     /* RAW 8 */
+     TEGRA_VIDEO_FORMAT(RAW8, 8, SRGGB8_1X8, 1, T_L8, SRGGB8),
+     TEGRA_VIDEO_FORMAT(RAW8, 8, SGRBG8_1X8, 1, T_L8, SGRBG8),
+     TEGRA_VIDEO_FORMAT(RAW8, 8, SGBRG8_1X8, 1, T_L8, SGBRG8),
+     TEGRA_VIDEO_FORMAT(RAW8, 8, SBGGR8_1X8, 1, T_L8, SBGGR8),
+     /* RAW 10 */
+     TEGRA_VIDEO_FORMAT(RAW10, 10, SRGGB10_1X10, 2, T_R16_I, SRGGB10),
+     TEGRA_VIDEO_FORMAT(RAW10, 10, SGRBG10_1X10, 2, T_R16_I, SGRBG10),
+     TEGRA_VIDEO_FORMAT(RAW10, 10, SGBRG10_1X10, 2, T_R16_I, SGBRG10),
+     TEGRA_VIDEO_FORMAT(RAW10, 10, SBGGR10_1X10, 2, T_R16_I, SBGGR10),
+     /* RAW 12 */
+     TEGRA_VIDEO_FORMAT(RAW12, 12, SRGGB12_1X12, 2, T_R16_I, SRGGB12),
+     TEGRA_VIDEO_FORMAT(RAW12, 12, SGRBG12_1X12, 2, T_R16_I, SGRBG12),
+     TEGRA_VIDEO_FORMAT(RAW12, 12, SGBRG12_1X12, 2, T_R16_I, SGBRG12),
+     TEGRA_VIDEO_FORMAT(RAW12, 12, SBGGR12_1X12, 2, T_R16_I, SBGGR12),
+     /* RGB888 */
+     TEGRA_VIDEO_FORMAT(RGB888, 24, RGB888_1X24, 4, T_A8R8G8B8, RGB24),
+     TEGRA_VIDEO_FORMAT(RGB888, 24, RGB888_1X32_PADHI, 4, T_A8B8G8R8,
+                        XBGR32),
+     /* YUV422 */
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, UYVY8_1X16, 2, T_U8_Y8__V8_Y8, UYVY),
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, VYUY8_1X16, 2, T_V8_Y8__U8_Y8, VYUY),
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, YUYV8_1X16, 2, T_Y8_U8__Y8_V8, YUYV),
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, YVYU8_1X16, 2, T_Y8_V8__Y8_U8, YVYU),
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, UYVY8_1X16, 1, T_Y8__V8U8_N422, NV16),
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, UYVY8_2X8, 2, T_U8_Y8__V8_Y8, UYVY),
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, VYUY8_2X8, 2, T_V8_Y8__U8_Y8, VYUY),
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, YUYV8_2X8, 2, T_Y8_U8__Y8_V8, YUYV),
+     TEGRA_VIDEO_FORMAT(YUV422_8, 16, YVYU8_2X8, 2, T_Y8_V8__Y8_U8, YVYU),
+};
+
+static const struct tegra_vi_ops tegra210_vi_ops = {
+     .vi_start_streaming = tegra210_vi_start_streaming,
+     .vi_stop_streaming = tegra210_vi_stop_streaming,
+};
+
+static const struct tegra_vi_soc tegra210_vi_soc = {
+     .video_formats = tegra210_video_formats,
+     .nformats = ARRAY_SIZE(tegra210_video_formats),
+     .ops = &tegra210_vi_ops,
+     .hw_revision = 3,
+     .vi_max_channels = 6,
+     .vi_max_clk_hz = 499200000,
+};
+
+static const struct of_device_id tegra_vi_of_id_table[] = {
+     { .compatible = "nvidia,tegra210-vi", .data = &tegra210_vi_soc },
+     { }
+};
+MODULE_DEVICE_TABLE(of, tegra_vi_of_id_table);
+
+static const struct dev_pm_ops tegra_vi_pm_ops = {
+     SET_RUNTIME_PM_OPS(vi_runtime_suspend, vi_runtime_resume, NULL)
+};
+
+struct platform_driver tegra_vi_driver = {
+     .driver = {
+             .name = "tegra-vi",
+             .of_match_table = tegra_vi_of_id_table,
+             .pm = &tegra_vi_pm_ops,
+     },
+     .probe = tegra_vi_probe,
+     .remove = tegra_vi_remove,
+};
+
+MODULE_AUTHOR("Sowjanya Komatineni <skomatineni@xxxxxxxxxx>");
+MODULE_DESCRIPTION("NVIDIA Tegra Video Input Device Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/staging/media/tegra/tegra-vi.h b/drivers/staging/media/tegra/tegra-vi.h
new file mode 100644
index 0000000..d639b36
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra-vi.h
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#ifndef __TEGRA_VI_H__
+#define __TEGRA_VI_H__
+
+#include <linux/host1x.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/videodev2.h>
+
+#include <media/media-device.h>
+#include <media/media-entity.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-dev.h>
+#include <media/videobuf2-v4l2.h>
+
+#include "tegra-common.h"
+
+/**
+ * struct tegra_vi_ops - Tegra VI operations
+ * @vi_start_streaming: starts media pipeline, subdevice streaming, sets up
+ *           VI for capture and runs capture start and capture finish
+ *           kthreads for capturing frames to buffer and returns them back.
+ * @vi_stop_streaming: stops media pipeline and subdevice streaming and returns
+ *           back any queued buffers.
+ */
+struct tegra_vi_ops {
+     int (*vi_start_streaming)(struct vb2_queue *vq, u32 count);
+     void (*vi_stop_streaming)(struct vb2_queue *vq);
+};
+
+/**
+ * struct tegra_vi_soc - NVIDIA Tegra Video Input SoC structure
+ *
+ * @video_formats: supported video formats
+ * @nformats: total video formats
+ * @ops: vi operations
+ * @hw_revision: VI hw_revision
+ * @vi_max_channels: supported max streaming channels
+ * @vi_max_clk_hz: VI clock max frequency
+ */
+struct tegra_vi_soc {
+     const struct tegra_video_format *video_formats;
+     const unsigned int nformats;
+     const struct tegra_vi_ops *ops;
+     u32 hw_revision;
+     unsigned int vi_max_channels;
+     unsigned int vi_max_clk_hz;
+};
+
+/**
+ * struct tegra_vi - NVIDIA Tegra Video Input device structure
+ *
+ * @dev: device struct
+ * @client: host1x_client struct
+ * @iomem: register base
+ * @vi_clk: main clock for VI block
+ * @vi_reg: regulator for VI hardware, normally it avdd_dsi_csi
+ * @soc: pointer to SoC data structure
+ * @ops: vi operations
+ * @vi_chans: list head for VI channels
+ */
+struct tegra_vi {
+     struct device *dev;
+     struct host1x_client client;
+     void __iomem *iomem;
+     struct clk *vi_clk;
+     struct regulator *vi_reg;
+     const struct tegra_vi_soc *soc;
+     const struct tegra_vi_ops *ops;
+     struct list_head vi_chans;
+};
+
+void tegra210_vi_stop_streaming(struct vb2_queue *vq);
+int tegra210_vi_start_streaming(struct vb2_queue *vq, u32 count);
+
+#endif /* __TEGRA_VI_H__ */
diff --git a/drivers/staging/media/tegra/tegra-video.c b/drivers/staging/media/tegra/tegra-video.c
new file mode 100644
index 0000000..bd3718e
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra-video.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#include <linux/host1x.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include "tegra-video.h"
+
+static void tegra_v4l2_dev_release(struct v4l2_device *v4l2_dev)
+{
+     struct tegra_video_device *vid;
+
+     vid = container_of(v4l2_dev, struct tegra_video_device, v4l2_dev);
+     v4l2_device_unregister(v4l2_dev);
+     kfree(vid);
+}
+
+static int host1x_video_probe(struct host1x_device *dev)
+{
+     struct tegra_video_device *vid;
+     int ret;
+
+     vid = kzalloc(sizeof(*vid), GFP_KERNEL);
+     if (!vid)
+             return -ENOMEM;
+
+     vid->media_dev.dev = get_device(&dev->dev);
+     strscpy(vid->media_dev.model, "NVIDIA Tegra Video Input Device",
+             sizeof(vid->media_dev.model));
+
+     media_device_init(&vid->media_dev);
+     ret = media_device_register(&vid->media_dev);
+     if (ret < 0) {
+             dev_err(vid->media_dev.dev,
+                     "failed to register media device: %d\n", ret);
+             goto cleanup;
+     }
+
+     vid->v4l2_dev.mdev = &vid->media_dev;
+     vid->v4l2_dev.release = tegra_v4l2_dev_release;
+     dev_set_drvdata(&dev->dev, vid);
+     ret = v4l2_device_register(vid->media_dev.dev, &vid->v4l2_dev);
+     if (ret < 0) {
+             dev_err(vid->media_dev.dev,
+                     "V4L2 device registration failed: %d\n", ret);
+             goto unregister_media;
+     }
+
+     ret = host1x_device_init(dev);
+     if (ret < 0)
+             goto unregister_v4l2;
+
+     return 0;
+
+unregister_v4l2:
+     v4l2_device_unregister(&vid->v4l2_dev);
+unregister_media:
+     media_device_unregister(&vid->media_dev);
+cleanup:
+     media_device_cleanup(&vid->media_dev);
+     kfree(vid);
+     return ret;
+}
+
+static int host1x_video_remove(struct host1x_device *dev)
+{
+     struct tegra_video_device *vid = dev_get_drvdata(&dev->dev);
+
+     host1x_device_exit(dev);
+     media_device_unregister(&vid->media_dev);
+     media_device_cleanup(&vid->media_dev);
+     v4l2_device_disconnect(&vid->v4l2_dev);
+     v4l2_device_put(&vid->v4l2_dev);
+     return 0;
+}
+
+static const struct of_device_id host1x_video_subdevs[] = {
+     { .compatible = "nvidia,tegra210-csi", },
+     { .compatible = "nvidia,tegra210-vi", },
+     { }
+};
+
+static struct host1x_driver host1x_video_driver = {
+     .driver = {
+             .name = "tegra-video",
+     },
+     .probe = host1x_video_probe,
+     .remove = host1x_video_remove,
+     .subdevs = host1x_video_subdevs,
+};
+
+static struct platform_driver * const drivers[] = {
+     &tegra_csi_driver,
+     &tegra_vi_driver,
+};
+
+static int __init host1x_video_init(void)
+{
+     int err;
+
+     err = host1x_driver_register(&host1x_video_driver);
+     if (err < 0)
+             return err;
+
+     err = platform_register_drivers(drivers, ARRAY_SIZE(drivers));
+     if (err < 0)
+             goto unregister_host1x;
+
+     return 0;
+
+unregister_host1x:
+     host1x_driver_unregister(&host1x_video_driver);
+     return err;
+}
+module_init(host1x_video_init);
+
+static void __exit host1x_video_exit(void)
+{
+     platform_unregister_drivers(drivers, ARRAY_SIZE(drivers));
+     host1x_driver_unregister(&host1x_video_driver);
+}
+module_exit(host1x_video_exit);
+
+MODULE_AUTHOR("Sowjanya Komatineni <skomatineni@xxxxxxxxxx>");
+MODULE_DESCRIPTION("NVIDIA Tegra Host1x Video driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/staging/media/tegra/tegra-video.h b/drivers/staging/media/tegra/tegra-video.h
new file mode 100644
index 0000000..1e2ae64
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra-video.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#ifndef __TEGRA_VIDEO_H__
+#define __TEGRA_VIDEO_H__
+
+#include <linux/host1x.h>
+
+#include <media/media-device.h>
+#include <media/media-entity.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-dev.h>
+#include <media/videobuf2-v4l2.h>
+
+#include "tegra-vi.h"
+#include "tegra-csi.h"
+
+struct tegra_video_device {
+     struct v4l2_device v4l2_dev;
+     struct media_device media_dev;
+     struct tegra_vi *vi;
+     struct tegra_csi *csi;
+};
+
+extern struct platform_driver tegra_vi_driver;
+extern struct platform_driver tegra_csi_driver;
+
+#endif
diff --git a/drivers/staging/media/tegra/tegra210.c b/drivers/staging/media/tegra/tegra210.c
new file mode 100644
index 0000000..eb547bb
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra210.c
@@ -0,0 +1,754 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+/*
+ * This source file contains both VI and CSI specific operations and
+ * registers accessors.
+ */
+#include <linux/clk.h>
+#include <linux/clk/tegra.h>
+#include <linux/delay.h>
+#include <linux/freezer.h>
+#include <linux/completion.h>
+
+#include "tegra-common.h"
+#include "tegra-csi.h"
+#include "tegra-vi.h"
+#include "tegra210.h"
+
+#define TEGRA210_CSI_PORT_OFFSET             0x34
+#define TEGRA210_CSI_CIL_OFFSET                      0x0f4
+#define TEGRA210_CSI_TPG_OFFSET                      0x18c
+
+#define CSI_PP_OFFSET(block)                 ((block) * 0x800)
+#define TEGRA210_VI_CSI_BASE(x)                      (0x100 + (x) * 0x100)
+
+/* Tegra210 VI registers accessors */
+static void tegra_vi_write(struct tegra_vi_channel *chan, unsigned int addr,
+                        u32 val)
+{
+     writel(val, chan->vi->iomem + addr);
+}
+
+static u32 tegra_vi_read(struct tegra_vi_channel *chan, unsigned int addr)
+{
+     return readl(chan->vi->iomem + addr);
+}
+
+/* Tegra210 VI_CSI registers accessors */
+static void vi_csi_write(struct tegra_vi_channel *chan, unsigned int addr,
+                      u32 val)
+{
+     void __iomem *vi_csi_base;
+
+     vi_csi_base = chan->vi->iomem + TEGRA210_VI_CSI_BASE(chan->portno);
+
+     writel(val, vi_csi_base + addr);
+}
+
+static u32 vi_csi_read(struct tegra_vi_channel *chan, unsigned int addr)
+{
+     void __iomem *vi_csi_base;
+
+     vi_csi_base = chan->vi->iomem + TEGRA210_VI_CSI_BASE(chan->portno);
+
+     return readl(vi_csi_base + addr);
+}
+
+/*
+ * Tegra210 VI channel capture operations
+ */
+static int tegra_channel_capture_setup(struct tegra_vi_channel *chan)
+{
+     u32 height = chan->format.height;
+     u32 width = chan->format.width;
+     u32 format = chan->fmtinfo->img_fmt;
+     u32 data_type = chan->fmtinfo->img_dt;
+     u32 word_count = (width * chan->fmtinfo->bit_width) / 8;
+
+     vi_csi_write(chan, TEGRA_VI_CSI_ERROR_STATUS, 0xffffffff);
+     vi_csi_write(chan, TEGRA_VI_CSI_IMAGE_DEF,
+                  ((chan->pg_mode ? 0 : 1) << BYPASS_PXL_TRANSFORM_OFFSET) |
+                  (format << IMAGE_DEF_FORMAT_OFFSET) |
+                  IMAGE_DEF_DEST_MEM);
+     vi_csi_write(chan, TEGRA_VI_CSI_IMAGE_DT, data_type);
+     vi_csi_write(chan, TEGRA_VI_CSI_IMAGE_SIZE_WC, word_count);
+     vi_csi_write(chan, TEGRA_VI_CSI_IMAGE_SIZE,
+                  (height << IMAGE_SIZE_HEIGHT_OFFSET) | width);
+     return 0;
+}
+
+static void tegra_channel_vi_soft_reset(struct tegra_vi_channel *chan)
+{
+     /* disable clock gating to enable continuous clock */
+     tegra_vi_write(chan, TEGRA_VI_CFG_CG_CTRL, 0);
+     /*
+      * Soft reset memory client interface, pixel format logic, sensor
+      * control logic, and a shadow copy logic to bring VI to clean state.
+      */
+     vi_csi_write(chan, TEGRA_VI_CSI_SW_RESET, 0xf);
+     usleep_range(100, 200);
+     vi_csi_write(chan, TEGRA_VI_CSI_SW_RESET, 0x0);
+
+     /* enable back VI clock gating */
+     tegra_vi_write(chan, TEGRA_VI_CFG_CG_CTRL, VI_CG_2ND_LEVEL_EN);
+}
+
+static void tegra_channel_capture_error_recover(struct tegra_vi_channel *chan)
+{
+     u32 val;
+
+     /*
+      * Recover VI and CSI hardware blocks in case of missing frame start
+      * events due to source not streaming or noisy csi inputs from the
+      * external source or many outstanding frame start or MW_ACK_DONE
+      * events which can cause CSI and VI hardware hang.
+      * This helps to have a clean capture for next frame.
+      */
+     val = vi_csi_read(chan, TEGRA_VI_CSI_ERROR_STATUS);
+     dev_dbg(&chan->video->dev, "TEGRA_VI_CSI_ERROR_STATUS 0x%08x\n", val);
+     vi_csi_write(chan, TEGRA_VI_CSI_ERROR_STATUS, val);
+
+     val = tegra_vi_read(chan, TEGRA_VI_CFG_VI_INCR_SYNCPT_ERROR);
+     dev_dbg(&chan->video->dev,
+             "TEGRA_VI_CFG_VI_INCR_SYNCPT_ERROR 0x%08x\n", val);
+     tegra_vi_write(chan, TEGRA_VI_CFG_VI_INCR_SYNCPT_ERROR, val);
+
+     /* disable the stream */
+     tegra_channel_set_stream(chan, false);
+
+     /* recover VI and CSI blocks by issuing software reset */
+     tegra_channel_csi_error_recover(chan);
+     tegra_channel_vi_soft_reset(chan);
+
+     /* re-init VI and enable back the stream */
+     tegra_channel_capture_setup(chan);
+     tegra_channel_set_stream(chan, true);
+}
+
+static struct tegra_channel_buffer *
+dequeue_buf_done(struct tegra_vi_channel *chan)
+{
+     struct tegra_channel_buffer *buf = NULL;
+
+     spin_lock(&chan->done_lock);
+     if (list_empty(&chan->done)) {
+             spin_unlock(&chan->done_lock);
+             return NULL;
+     }
+
+     buf = list_entry(chan->done.next, struct tegra_channel_buffer,
+                      queue);
+     if (buf)
+             list_del_init(&buf->queue);
+
+     spin_unlock(&chan->done_lock);
+
+     return buf;
+}
+
+static void release_buffer(struct tegra_vi_channel *chan,
+                        struct tegra_channel_buffer *buf,
+                        enum vb2_buffer_state state)
+{
+     struct vb2_v4l2_buffer *vb = &buf->buf;
+
+     vb->sequence = chan->sequence++;
+     vb->field = V4L2_FIELD_NONE;
+     vb->vb2_buf.timestamp = ktime_get_ns();
+     vb2_buffer_done(&vb->vb2_buf, state);
+}
+
+static int tegra_channel_capture_frame(struct tegra_vi_channel *chan,
+                                    struct tegra_channel_buffer *buf)
+{
+     int err = 0;
+     u32 thresh, value, frame_start, mw_ack_done;
+     int bytes_per_line = chan->format.bytesperline;
+
+     /* program buffer address by using surface 0 */
+     vi_csi_write(chan, TEGRA_VI_CSI_SURFACE0_OFFSET_MSB,
+                  (u64)buf->addr >> 32);
+     vi_csi_write(chan, TEGRA_VI_CSI_SURFACE0_OFFSET_LSB, buf->addr);
+     vi_csi_write(chan, TEGRA_VI_CSI_SURFACE0_STRIDE, bytes_per_line);
+
+     /*
+      * Tegra VI block interacts with host1x syncpt for synchronizing
+      * programmed condition of capture state and hardware operation.
+      * Frame start and Memory write acknowledge syncpts has their own
+      * FIFO of depth 2.
+      *
+      * Syncpoint trigger conditions set through VI_INCR_SYNCPT register
+      * are added to HW syncpt FIFO and when the HW triggers, syncpt
+      * condition is removed from the FIFO and counter at syncpoint index
+      * will be incremented by the hardware and software can wait for
+      * counter to reach threshold to synchronize capturing frame with the
+      * hardware capture events.
+      */
+
+     /* increase channel syncpoint threshold for FRAME_START */
+     thresh = host1x_syncpt_incr_max(chan->frame_start_sp, 1);
+
+     /* Program FRAME_START trigger condition syncpt request */
+     frame_start = VI_CSI_PP_FRAME_START(chan->portno);
+     value = VI_CFG_VI_INCR_SYNCPT_COND(frame_start) |
+             host1x_syncpt_id(chan->frame_start_sp);
+     tegra_vi_write(chan, TEGRA_VI_CFG_VI_INCR_SYNCPT, value);
+
+     /* increase channel syncpoint threshold for MW_ACK_DONE */
+     buf->mw_ack_sp_thresh = host1x_syncpt_incr_max(chan->mw_ack_sp, 1);
+
+     /* Program MW_ACK_DONE trigger condition syncpt request */
+     mw_ack_done = VI_CSI_MW_ACK_DONE(chan->portno);
+     value = VI_CFG_VI_INCR_SYNCPT_COND(mw_ack_done) |
+             host1x_syncpt_id(chan->mw_ack_sp);
+     tegra_vi_write(chan, TEGRA_VI_CFG_VI_INCR_SYNCPT, value);
+
+     /* enable single shot capture */
+     vi_csi_write(chan, TEGRA_VI_CSI_SINGLE_SHOT, SINGLE_SHOT_CAPTURE);
+     chan->capture_reqs++;
+
+     /* wait for syncpt counter to reach frame start event threshold */
+     err = host1x_syncpt_wait(chan->frame_start_sp, thresh,
+                              TEGRA_VI_SYNCPT_WAIT_TIMEOUT, &value);
+     if (err) {
+             dev_err(&chan->video->dev,
+                     "frame start syncpt timeout: %d\n", err);
+             /* increment syncpoint counter for timedout events */
+             host1x_syncpt_incr(chan->frame_start_sp);
+             spin_lock(&chan->sp_incr_lock);
+             host1x_syncpt_incr(chan->mw_ack_sp);
+             spin_unlock(&chan->sp_incr_lock);
+             /* clear errors and recover */
+             tegra_channel_capture_error_recover(chan);
+             release_buffer(chan, buf, VB2_BUF_STATE_ERROR);
+             return err;
+     }
+
+     /* move buffer to capture done queue */
+     spin_lock(&chan->done_lock);
+     list_add_tail(&buf->queue, &chan->done);
+     spin_unlock(&chan->done_lock);
+
+     /* wait up kthread for capture done */
+     wake_up_interruptible(&chan->done_wait);
+
+     return 0;
+}
+
+static void tegra_channel_capture_done(struct tegra_vi_channel *chan,
+                                    struct tegra_channel_buffer *buf)
+{
+     enum vb2_buffer_state state = VB2_BUF_STATE_DONE;
+     u32 value;
+     int ret;
+
+     /* wait for syncpt counter to reach MW_ACK_DONE event threshold */
+     ret = host1x_syncpt_wait(chan->mw_ack_sp, buf->mw_ack_sp_thresh,
+                              TEGRA_VI_SYNCPT_WAIT_TIMEOUT, &value);
+     if (ret) {
+             dev_err(&chan->video->dev,
+                     "MW_ACK_DONE syncpt timeout: %d\n", ret);
+             state = VB2_BUF_STATE_ERROR;
+             /* increment syncpoint counter for timedout event */
+             spin_lock(&chan->sp_incr_lock);
+             host1x_syncpt_incr(chan->mw_ack_sp);
+             spin_unlock(&chan->sp_incr_lock);
+     }
+
+     release_buffer(chan, buf, state);
+}
+
+static int chan_capture_kthread_start(void *data)
+{
+     struct tegra_vi_channel *chan = data;
+     struct tegra_channel_buffer *buf;
+     int err = 0;
+     int caps_inflight;
+
+     set_freezable();
Do you have a particular reason to use a kernel thread, instead of using
the context of the user process (or threaded interrupt handler)?

We can't use threaded interrupt handler for VI/CSI host1x clients as all capture events in driver are synchronized through hardware sync point counters.

sync point driver is part of host1x driver and is used by all host1x clients to track events.

+
+     while (1) {
+             try_to_freeze();
+
+             wait_event_interruptible(chan->start_wait,
+                                      !list_empty(&chan->capture) ||
+                                      kthread_should_stop());
+             /*
+              * Frame start and MW_ACK_DONE syncpoint condition FIFOs are
+              * of max depth 2. So make sure max 2 capture requests are
+              * in process by the hardware at a time.
+              */
+             while (!(kthread_should_stop() || list_empty(&chan->capture))) {
+                     caps_inflight = chan->capture_reqs - chan->sequence;
+                     /*
+                      * Source is not streaming if error is non-zero.
+                      * So, do not dequeue buffers on capture error or when
+                      * syncpoint requests in FIFO are full.
+                      */
+                     if (err || caps_inflight >= SYNCPT_FIFO_DEPTH)
+                             break;
+
+                     /* dequeue the buffer and start capture */
+                     spin_lock(&chan->start_lock);
+                     if (list_empty(&chan->capture))
+                             break;
+                     buf = list_entry(chan->capture.next,
+                                      struct tegra_channel_buffer, queue);
+                     list_del_init(&buf->queue);
+                     spin_unlock(&chan->start_lock);
+
+                     err = tegra_channel_capture_frame(chan, buf);
+                     if (err)
+                             vb2_queue_error(&chan->queue);
+             }
+
+             if (kthread_should_stop())
+                     break;
+     }
+
+     return 0;
+}
+
+static int chan_capture_kthread_finish(void *data)
+{
+     struct tegra_vi_channel *chan = data;
+     struct tegra_channel_buffer *buf;
+
+     set_freezable();
+
+     while (1) {
+             try_to_freeze();
+
+             wait_event_interruptible(chan->done_wait,
+                                      !list_empty(&chan->done) ||
+                                      kthread_should_stop());
+             /* dequeue buffers and finish capture */
+             buf = dequeue_buf_done(chan);
+             while (buf) {
+                     tegra_channel_capture_done(chan, buf);
+                     buf = dequeue_buf_done(chan);
+             }
+
+             if (kthread_should_stop())
+                     break;
+     }
+
+     return 0;
+}
+
+int tegra210_vi_start_streaming(struct vb2_queue *vq, u32 count)
+{
+     struct tegra_vi_channel *chan = vb2_get_drv_priv(vq);
+     struct media_pipeline *pipe = &chan->video->pipe;
+     int ret;
+
+     tegra_vi_write(chan, TEGRA_VI_CFG_CG_CTRL, VI_CG_2ND_LEVEL_EN);
+
+     /* clear errors */
+     vi_csi_write(chan, TEGRA_VI_CSI_ERROR_STATUS, 0xffffffff);
+
+     /*
+      * Sync point FIFO full stalls the host interface.
+      * Setting NO_STALL will drop INCR_SYNCPT methods when fifos are
+      * full and the corresponding condition bits in INCR_SYNCPT_ERROR
+      * register will be set.
+      * This allows SW to process error recovery.
+      */
+     tegra_vi_write(chan, TEGRA_VI_CFG_VI_INCR_SYNCPT_CNTRL,
+                    TEGRA_VI_CFG_VI_INCR_SYNCPT_NO_STALL);
+
+     /* start the pipeline */
+     ret = media_pipeline_start(&chan->video->entity, pipe);
+     if (ret < 0)
+             goto error_pipeline_start;
+
+     tegra_channel_capture_setup(chan);
+     ret = tegra_channel_set_stream(chan, true);
+     if (ret < 0)
+             goto error_set_stream;
+
+     chan->capture_reqs = 0;
+     chan->sequence = 0;
+
+     /* start kthreads to capture data to buffer and return them */
+     chan->kthread_start_capture = kthread_run(chan_capture_kthread_start,
+                                               chan, "%s:0",
+                                               chan->video->name);
+     if (IS_ERR(chan->kthread_start_capture)) {
+             ret = PTR_ERR(chan->kthread_start_capture);
+             chan->kthread_start_capture = NULL;
+             dev_err(&chan->video->dev,
+                     "failed to run capture start kthread: %d\n", ret);
+             goto error_kthread_start;
+     }
+
+     chan->kthread_finish_capture = kthread_run(chan_capture_kthread_finish,
+                                                chan, "%s:1",
+                                                chan->video->name);
+     if (IS_ERR(chan->kthread_finish_capture)) {
+             ret = PTR_ERR(chan->kthread_finish_capture);
+             chan->kthread_finish_capture = NULL;
+             dev_err(&chan->video->dev,
+                     "failed to run capture finish kthread: %d\n", ret);
+             goto error_kthread_done;
+     }
+
+     return 0;
+
+error_kthread_done:
+     kthread_stop(chan->kthread_start_capture);
+error_kthread_start:
+     tegra_channel_set_stream(chan, false);
+error_set_stream:
+     media_pipeline_stop(&chan->video->entity);
+error_pipeline_start:
+     vq->start_streaming_called = 0;
+     tegra_channel_release_buffers(chan, VB2_BUF_STATE_QUEUED);
+     return ret;
+}
+
+void tegra210_vi_stop_streaming(struct vb2_queue *vq)
+{
+     struct tegra_vi_channel *chan = vb2_get_drv_priv(vq);
+
+     if (chan->kthread_start_capture) {
+             kthread_stop(chan->kthread_start_capture);
+             chan->kthread_start_capture = NULL;
+     }
+
+     if (chan->kthread_finish_capture) {
+             kthread_stop(chan->kthread_finish_capture);
+             chan->kthread_finish_capture = NULL;
+     }
+
+     tegra_channel_release_buffers(chan, VB2_BUF_STATE_ERROR);
+     tegra_channel_set_stream(chan, false);
+     media_pipeline_stop(&chan->video->entity);
+}
+
+/* Tegra210 CSI PHY registers accessors */
+static void csi_write(struct tegra_csi *csi, u8 portno, unsigned int addr,
+                   u32 val)
+{
+     void __iomem *csi_pp_base;
+
+     csi_pp_base = csi->iomem + CSI_PP_OFFSET(portno >> 1);
+
+     writel(val, csi_pp_base + addr);
+}
+
+/* Tegra210 CSI Pixel parser registers accessors */
+static void pp_write(struct tegra_csi *csi, u8 portno, u32 addr, u32 val)
+{
+     void __iomem *csi_pp_base;
+     unsigned int offset;
+
+     csi_pp_base = csi->iomem + CSI_PP_OFFSET(portno >> 1);
+     offset = (portno % CSI_PORTS_PER_BRICK) * TEGRA210_CSI_PORT_OFFSET;
+
+     writel(val, csi_pp_base + offset + addr);
+}
+
+static u32 pp_read(struct tegra_csi *csi, u8 portno, u32 addr)
+{
+     void __iomem *csi_pp_base;
+     unsigned int offset;
+
+     csi_pp_base = csi->iomem + CSI_PP_OFFSET(portno >> 1);
+     offset = (portno % CSI_PORTS_PER_BRICK) * TEGRA210_CSI_PORT_OFFSET;
+
+     return readl(csi_pp_base + offset + addr);
+}
+
+/* Tegra210 CSI CIL A/B port registers accessors */
+static void cil_write(struct tegra_csi *csi, u8 portno, u32 addr, u32 val)
+{
+     void __iomem *csi_cil_base;
+     unsigned int offset;
+
+     csi_cil_base = csi->iomem + CSI_PP_OFFSET(portno >> 1) +
+                    TEGRA210_CSI_CIL_OFFSET;
+     offset = (portno % CSI_PORTS_PER_BRICK) * TEGRA210_CSI_PORT_OFFSET;
+
+     writel(val, csi_cil_base + offset + addr);
+}
+
+static u32 cil_read(struct tegra_csi *csi, u8 portno, u32 addr)
+{
+     void __iomem *csi_cil_base;
+     unsigned int offset;
+
+     csi_cil_base = csi->iomem + CSI_PP_OFFSET(portno >> 1) +
+                    TEGRA210_CSI_CIL_OFFSET;
+     offset = (portno % CSI_PORTS_PER_BRICK) * TEGRA210_CSI_PORT_OFFSET;
+
+     return readl(csi_cil_base + offset + addr);
+}
+
+/* Tegra210 CSI Test pattern generator registers accessor */
+static void tpg_write(struct tegra_csi *csi, u8 portno, unsigned int addr,
+                   u32 val)
+{
+     void __iomem *csi_pp_base;
+     unsigned int offset;
+
+     csi_pp_base = csi->iomem + CSI_PP_OFFSET(portno >> 1);
+     offset = (portno % CSI_PORTS_PER_BRICK) * TEGRA210_CSI_PORT_OFFSET +
+              TEGRA210_CSI_TPG_OFFSET;
+
+     writel(val, csi_pp_base + offset + addr);
+}
+
+/*
+ * Tegra210 CSI operations
+ */
+void tegra210_csi_error_recover(struct tegra_csi_channel *csi_chan)
+{
+     struct tegra_csi *csi = csi_chan->csi;
+     unsigned int port_num = csi_chan->csi_port_num;
+     u32 val;
+
+     /*
+      * Recover CSI hardware in case of capture errors by issuing
+      * software reset to CSICIL sensor, pixel parser, and clear errors
+      * to have clean capture on  next streaming.
+      */
+     val = pp_read(csi, port_num, TEGRA_CSI_PIXEL_PARSER_STATUS);
+     dev_dbg(csi->dev, "TEGRA_CSI_PIXEL_PARSER_STATUS 0x%08x\n", val);
+
+     val = cil_read(csi, port_num, TEGRA_CSI_CIL_STATUS);
+     dev_dbg(csi->dev, "TEGRA_CSI_CIL_STATUS 0x%08x\n", val);
+
+     val = cil_read(csi, port_num, TEGRA_CSI_CILX_STATUS);
+     dev_dbg(csi->dev, "TEGRA_CSI_CILX_STATUS 0x%08x\n", val);
+
+     if (csi_chan->numlanes == 4) {
+             /* reset CSI CIL sensor */
+             cil_write(csi, port_num, TEGRA_CSI_CIL_SW_SENSOR_RESET, 0x1);
+             cil_write(csi, port_num + 1,
+                       TEGRA_CSI_CIL_SW_SENSOR_RESET, 0x1);
+             /*
+              * SW_STATUS_RESET resets all status bits of PPA, PPB, CILA,
+              * CILB status registers and debug counters.
+              * So, SW_STATUS_RESET can be used only when CSI Brick is in
+              * x4 mode.
+              */
+             csi_write(csi, port_num, TEGRA_CSI_CSI_SW_STATUS_RESET, 0x1);
+
+             /* sleep for 20 clock cycles to drain the FIFO */
+             usleep_range(10, 20);
+
+             cil_write(csi, port_num + 1,
+                       TEGRA_CSI_CIL_SW_SENSOR_RESET, 0x0);
+             cil_write(csi, port_num, TEGRA_CSI_CIL_SW_SENSOR_RESET, 0x0);
+             csi_write(csi, port_num, TEGRA_CSI_CSI_SW_STATUS_RESET, 0x0);
+     } else {
+             /* reset CSICIL sensor */
+             cil_write(csi, port_num, TEGRA_CSI_CIL_SW_SENSOR_RESET, 0x1);
+             usleep_range(10, 20);
+             cil_write(csi, port_num, TEGRA_CSI_CIL_SW_SENSOR_RESET, 0x0);
+
+             /* clear the errors */
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_PARSER_STATUS,
+                      0xffffffff);
+             cil_write(csi, port_num, TEGRA_CSI_CIL_STATUS, 0xffffffff);
+             cil_write(csi, port_num, TEGRA_CSI_CILX_STATUS, 0xffffffff);
+     }
+}
+
+int tegra210_csi_streaming(struct tegra_csi_channel *csi_chan, u8 pg_mode,
+                        int enable)
+{
+     struct tegra_csi *csi = csi_chan->csi;
+     unsigned int port_num = csi_chan->csi_port_num;
+
+     if (enable) {
+             csi_write(csi, port_num, TEGRA_CSI_CLKEN_OVERRIDE, 0);
+
+             /* clean up status */
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_PARSER_STATUS,
+                      0xffffffff);
+             cil_write(csi, port_num, TEGRA_CSI_CIL_STATUS, 0xffffffff);
+             cil_write(csi, port_num, TEGRA_CSI_CILX_STATUS, 0xffffffff);
+             cil_write(csi, port_num, TEGRA_CSI_CIL_INTERRUPT_MASK, 0x0);
+
+             /* CIL PHY registers setup */
+             cil_write(csi, port_num, TEGRA_CSI_CIL_PAD_CONFIG0, 0x0);
+             cil_write(csi, port_num, TEGRA_CSI_CIL_PHY_CONTROL, 0xa);
+
+             /*
+              * The CSI unit provides for connection of up to six cameras in
+              * the system and is organized as three identical instances of
+              * two MIPI support blocks, each with a separate 4-lane
+              * interface that can be configured as a single camera with 4
+              * lanes or as a dual camera with 2 lanes available for each
+              * camera.
+              */
+             if (csi_chan->numlanes == 4) {
+                     cil_write(csi, port_num + 1,
+                               TEGRA_CSI_CIL_STATUS, 0xffffffff);
+                     cil_write(csi, port_num + 1,
+                               TEGRA_CSI_CILX_STATUS, 0xffffffff);
+                     cil_write(csi, port_num + 1,
+                               TEGRA_CSI_CIL_INTERRUPT_MASK, 0x0);
+
+                     cil_write(csi, port_num,
+                               TEGRA_CSI_CIL_PAD_CONFIG0, BRICK_CLOCK_A_4X);
+                     cil_write(csi, port_num + 1,
+                               TEGRA_CSI_CIL_PAD_CONFIG0, 0x0);
+                     cil_write(csi, port_num + 1,
+                               TEGRA_CSI_CIL_INTERRUPT_MASK, 0x0);
+                     cil_write(csi, port_num + 1,
+                               TEGRA_CSI_CIL_PHY_CONTROL, 0xa);
+                     csi_write(csi, port_num, TEGRA_CSI_PHY_CIL_COMMAND,
+                               CSI_A_PHY_CIL_ENABLE | CSI_B_PHY_CIL_ENABLE);
+             } else {
+                     u32 val = ((port_num & 1) == PORT_A) ?
+                               CSI_A_PHY_CIL_ENABLE | CSI_B_PHY_CIL_NOP :
+                               CSI_B_PHY_CIL_ENABLE | CSI_A_PHY_CIL_NOP;
+                     csi_write(csi, port_num, TEGRA_CSI_PHY_CIL_COMMAND,
+                               val);
+             }
+
+             /* CSI pixel parser registers setup */
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_STREAM_PP_COMMAND,
+                      (0xf << CSI_PP_START_MARKER_FRAME_MAX_OFFSET) |
+                      CSI_PP_SINGLE_SHOT_ENABLE | CSI_PP_RST);
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_PARSER_INTERRUPT_MASK,
+                      0x0);
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_STREAM_CONTROL0,
+                      CSI_PP_PACKET_HEADER_SENT |
+                      CSI_PP_DATA_IDENTIFIER_ENABLE |
+                      CSI_PP_WORD_COUNT_SELECT_HEADER |
+                      CSI_PP_CRC_CHECK_ENABLE |  CSI_PP_WC_CHECK |
+                      CSI_PP_OUTPUT_FORMAT_STORE | CSI_PPA_PAD_LINE_NOPAD |
+                      CSI_PP_HEADER_EC_DISABLE | CSI_PPA_PAD_FRAME_NOPAD |
+                      (port_num & 1));
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_STREAM_CONTROL1,
+                      (0x1 << CSI_PP_TOP_FIELD_FRAME_OFFSET) |
+                      (0x1 << CSI_PP_TOP_FIELD_FRAME_MASK_OFFSET));
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_STREAM_GAP,
+                      0x14 << PP_FRAME_MIN_GAP_OFFSET);
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_STREAM_EXPECTED_FRAME,
+                      0x0);
+             pp_write(csi, port_num, TEGRA_CSI_INPUT_STREAM_CONTROL,
+                      (0x3f << CSI_SKIP_PACKET_THRESHOLD_OFFSET) |
+                      (csi_chan->numlanes - 1));
+
+             /* TPG setup */
+             if (pg_mode) {
+                     tpg_write(csi, port_num,
+                               TEGRA_CSI_PATTERN_GENERATOR_CTRL,
+                               ((pg_mode - 1) << PG_MODE_OFFSET) |
+                               PG_ENABLE);
+                     tpg_write(csi, port_num, TEGRA_CSI_PG_BLANK,
+                               8 << PG_VBLANK_OFFSET | 512);
+                     tpg_write(csi, port_num, TEGRA_CSI_PG_PHASE, 0x0);
+                     tpg_write(csi, port_num, TEGRA_CSI_PG_RED_FREQ,
+                               (0x10 << PG_RED_VERT_INIT_FREQ_OFFSET) |
+                               (0x10 << PG_RED_HOR_INIT_FREQ_OFFSET));
+                     tpg_write(csi, port_num, TEGRA_CSI_PG_RED_FREQ_RATE,
+                               0x0);
+                     tpg_write(csi, port_num, TEGRA_CSI_PG_GREEN_FREQ,
+                               (0x10 << PG_GREEN_VERT_INIT_FREQ_OFFSET) |
+                               (0x10 << PG_GREEN_HOR_INIT_FREQ_OFFSET));
+                     tpg_write(csi, port_num, TEGRA_CSI_PG_GREEN_FREQ_RATE,
+                               0x0);
+                     tpg_write(csi, port_num, TEGRA_CSI_PG_BLUE_FREQ,
+                               (0x10 << PG_BLUE_VERT_INIT_FREQ_OFFSET) |
+                               (0x10 << PG_BLUE_HOR_INIT_FREQ_OFFSET));
+                     tpg_write(csi, port_num, TEGRA_CSI_PG_BLUE_FREQ_RATE,
+                               0x0);
+             }
+
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_STREAM_PP_COMMAND,
+                      (0xf << CSI_PP_START_MARKER_FRAME_MAX_OFFSET) |
+                      CSI_PP_SINGLE_SHOT_ENABLE | CSI_PP_ENABLE);
+     } else {
+             u32 val = pp_read(csi, port_num,
+                               TEGRA_CSI_PIXEL_PARSER_STATUS);
+
+             dev_dbg(csi->dev, "TEGRA_CSI_PIXEL_PARSER_STATUS 0x%08x\n",
+                     val);
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_PARSER_STATUS, val);
+
+             val = cil_read(csi, port_num, TEGRA_CSI_CIL_STATUS);
+             dev_dbg(csi->dev, "TEGRA_CSI_CIL_STATUS 0x%08x\n", val);
+             cil_write(csi, port_num, TEGRA_CSI_CIL_STATUS, val);
+
+             val = cil_read(csi, port_num, TEGRA_CSI_CILX_STATUS);
+             dev_dbg(csi->dev, "TEGRA_CSI_CILX_STATUS 0x%08x\n", val);
+             cil_write(csi, port_num, TEGRA_CSI_CILX_STATUS, val);
+
+             pp_write(csi, port_num, TEGRA_CSI_PIXEL_STREAM_PP_COMMAND,
+                      (0xf << CSI_PP_START_MARKER_FRAME_MAX_OFFSET) |
+                      CSI_PP_DISABLE);
+
+             if (pg_mode) {
+                     tpg_write(csi, port_num,
+                               TEGRA_CSI_PATTERN_GENERATOR_CTRL,
+                               PG_DISABLE);
+                     return 0;
+             }
+
+             if (csi_chan->numlanes == 4) {
+                     csi_write(csi, port_num, TEGRA_CSI_PHY_CIL_COMMAND,
+                               CSI_A_PHY_CIL_DISABLE |
+                               CSI_B_PHY_CIL_DISABLE);
+
+             } else {
+                     u32 val = ((port_num & 1) == PORT_A) ?
+                               CSI_A_PHY_CIL_DISABLE | CSI_B_PHY_CIL_NOP :
+                               CSI_B_PHY_CIL_DISABLE | CSI_A_PHY_CIL_NOP;
+                     csi_write(csi, port_num, TEGRA_CSI_PHY_CIL_COMMAND,
+                               val);
+             }
+     }
+
+     return 0;
+}
+
+int tegra210_csi_hw_init(struct tegra_csi *csi)
+{
+     int ret;
+
+     csi->csi_clk = devm_clk_get(csi->dev, "csi");
+     if (IS_ERR(csi->csi_clk)) {
+             ret = PTR_ERR(csi->csi_clk);
+             dev_err(csi->dev, "failed to get csi clock: %d\n", ret);
+             return ret;
+     }
+
+     csi->tpg_clk = devm_clk_get(csi->dev, "csi_tpg");
+     if (IS_ERR(csi->tpg_clk)) {
+             ret = PTR_ERR(csi->tpg_clk);
+             dev_err(csi->dev, "failed to get csi_tpg clock: %d\n", ret);
+             return ret;
+     }
+
+     csi->cilab_clk = devm_clk_get(csi->dev, "cilab");
+     if (IS_ERR(csi->cilab_clk)) {
+             ret = PTR_ERR(csi->cilab_clk);
+             dev_err(csi->dev, "failed to get cilab clock: %d\n", ret);
+             return ret;
+     }
+
+     csi->cilcd_clk = devm_clk_get(csi->dev, "cilcd");
+     if (IS_ERR(csi->cilcd_clk)) {
+             ret = PTR_ERR(csi->cilcd_clk);
+             dev_err(csi->dev, "failed to get cilcd clock: %d\n", ret);
+             return ret;
+     }
+
+     csi->cilef_clk = devm_clk_get(csi->dev, "cile");
+     if (IS_ERR(csi->cilef_clk)) {
+             ret = PTR_ERR(csi->cilef_clk);
+             dev_err(csi->dev, "failed to get cile clock: %d\n", ret);
+             return ret;
+     }
+
devm_clk_bulk_get()?

+     return 0;
+}
diff --git a/drivers/staging/media/tegra/tegra210.h b/drivers/staging/media/tegra/tegra210.h
new file mode 100644
index 0000000..c4548c5
--- /dev/null
+++ b/drivers/staging/media/tegra/tegra210.h
@@ -0,0 +1,192 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
+ */
+
+#ifndef __TEGRA210_H__
+#define __TEGRA210_H__
+
+/* Tegra210 VI registers */
+#define TEGRA_VI_SYNCPT_WAIT_TIMEOUT                 msecs_to_jiffies(200)
+#define TEGRA_VI_CFG_VI_INCR_SYNCPT                  0x000
+#define   VI_CFG_VI_INCR_SYNCPT_COND(x)                      (((x) & 0xff) << 8)
+#define   VI_CSI_PP_LINE_START(port)                 (4 + (port) * 4)
+#define   VI_CSI_PP_FRAME_START(port)                        (5 + (port) * 4)
+#define   VI_CSI_MW_REQ_DONE(port)                   (6 + (port) * 4)
+#define   VI_CSI_MW_ACK_DONE(port)                   (7 + (port) * 4)
+#define SYNCPT_FIFO_DEPTH                            2
+
+#define TEGRA_VI_CFG_VI_INCR_SYNCPT_CNTRL            0x004
+#define TEGRA_VI_CFG_VI_INCR_SYNCPT_NO_STALL         BIT(8)
+#define TEGRA_VI_CFG_VI_INCR_SYNCPT_ERROR            0x008
+#define TEGRA_VI_CFG_CTXSW                           0x020
+#define TEGRA_VI_CFG_INTSTATUS                               0x024
+#define TEGRA_VI_CFG_PWM_CONTROL                     0x038
+#define TEGRA_VI_CFG_PWM_HIGH_PULSE                  0x03c
+#define TEGRA_VI_CFG_PWM_LOW_PULSE                   0x040
+#define TEGRA_VI_CFG_PWM_SELECT_PULSE_A                      0x044
+#define TEGRA_VI_CFG_PWM_SELECT_PULSE_B                      0x048
+#define TEGRA_VI_CFG_PWM_SELECT_PULSE_C                      0x04c
+#define TEGRA_VI_CFG_PWM_SELECT_PULSE_D                      0x050
+#define TEGRA_VI_CFG_VGP1                            0x064
+#define TEGRA_VI_CFG_VGP2                            0x068
+#define TEGRA_VI_CFG_VGP3                            0x06c
+#define TEGRA_VI_CFG_VGP4                            0x070
+#define TEGRA_VI_CFG_VGP5                            0x074
+#define TEGRA_VI_CFG_VGP6                            0x078
+#define TEGRA_VI_CFG_INTERRUPT_MASK                  0x08c
+#define TEGRA_VI_CFG_INTERRUPT_TYPE_SELECT           0x090
+#define TEGRA_VI_CFG_INTERRUPT_POLARITY_SELECT               0x094
+#define TEGRA_VI_CFG_INTERRUPT_STATUS                        0x098
+#define TEGRA_VI_CFG_VGP_SYNCPT_CONFIG                       0x0ac
+#define TEGRA_VI_CFG_VI_SW_RESET                     0x0b4
+#define TEGRA_VI_CFG_CG_CTRL                         0x0b8
+#define   VI_CG_2ND_LEVEL_EN                         0x1
+#define TEGRA_VI_CFG_VI_MCCIF_FIFOCTRL                       0x0e4
+#define TEGRA_VI_CFG_TIMEOUT_WCOAL_VI                        0x0e8
+#define TEGRA_VI_CFG_DVFS                            0x0f0
+#define TEGRA_VI_CFG_RESERVE                         0x0f4
+#define TEGRA_VI_CFG_RESERVE_1                               0x0f8
+
+/* Tegra210 CSI registers */
+#define TEGRA_VI_CSI_SW_RESET                                0x000
+#define TEGRA_VI_CSI_SINGLE_SHOT                     0x004
+#define   SINGLE_SHOT_CAPTURE                                0x1
+#define TEGRA_VI_CSI_SINGLE_SHOT_STATE_UPDATE                0x008
+#define TEGRA_VI_CSI_IMAGE_DEF                               0x00c
+#define   BYPASS_PXL_TRANSFORM_OFFSET                        24
+#define   IMAGE_DEF_FORMAT_OFFSET                    16
+#define   IMAGE_DEF_DEST_MEM                         0x1
+#define TEGRA_VI_CSI_RGB2Y_CTRL                              0x010
+#define TEGRA_VI_CSI_MEM_TILING                              0x014
+#define TEGRA_VI_CSI_IMAGE_SIZE                              0x018
+#define   IMAGE_SIZE_HEIGHT_OFFSET                   16
+#define TEGRA_VI_CSI_IMAGE_SIZE_WC                   0x01c
+#define TEGRA_VI_CSI_IMAGE_DT                                0x020
+#define TEGRA_VI_CSI_SURFACE0_OFFSET_MSB             0x024
+#define TEGRA_VI_CSI_SURFACE0_OFFSET_LSB             0x028
+#define TEGRA_VI_CSI_SURFACE1_OFFSET_MSB             0x02c
+#define TEGRA_VI_CSI_SURFACE1_OFFSET_LSB             0x030
+#define TEGRA_VI_CSI_SURFACE2_OFFSET_MSB             0x034
+#define TEGRA_VI_CSI_SURFACE2_OFFSET_LSB             0x038
+#define TEGRA_VI_CSI_SURFACE0_BF_OFFSET_MSB          0x03c
+#define TEGRA_VI_CSI_SURFACE0_BF_OFFSET_LSB          0x040
+#define TEGRA_VI_CSI_SURFACE1_BF_OFFSET_MSB          0x044
+#define TEGRA_VI_CSI_SURFACE1_BF_OFFSET_LSB          0x048
+#define TEGRA_VI_CSI_SURFACE2_BF_OFFSET_MSB          0x04c
+#define TEGRA_VI_CSI_SURFACE2_BF_OFFSET_LSB          0x050
+#define TEGRA_VI_CSI_SURFACE0_STRIDE                 0x054
+#define TEGRA_VI_CSI_SURFACE1_STRIDE                 0x058
+#define TEGRA_VI_CSI_SURFACE2_STRIDE                 0x05c
+#define TEGRA_VI_CSI_SURFACE_HEIGHT0                 0x060
+#define TEGRA_VI_CSI_ISPINTF_CONFIG                  0x064
+#define TEGRA_VI_CSI_ERROR_STATUS                    0x084
+#define TEGRA_VI_CSI_ERROR_INT_MASK                  0x088
+#define TEGRA_VI_CSI_WD_CTRL                         0x08c
+#define TEGRA_VI_CSI_WD_PERIOD                               0x090
+
+/* Tegra210 CSI Pixel Parser registers: Starts from 0x838, offset 0x0 */
+#define TEGRA_CSI_INPUT_STREAM_CONTROL                  0x000
+#define   CSI_SKIP_PACKET_THRESHOLD_OFFSET           16
+
+#define TEGRA_CSI_PIXEL_STREAM_CONTROL0                      0x004
+#define   CSI_PP_PACKET_HEADER_SENT                  BIT(4)
+#define   CSI_PP_DATA_IDENTIFIER_ENABLE                      BIT(5)
+#define   CSI_PP_WORD_COUNT_SELECT_HEADER            BIT(6)
+#define   CSI_PP_CRC_CHECK_ENABLE                    BIT(7)
+#define   CSI_PP_WC_CHECK                            BIT(8)
+#define   CSI_PP_OUTPUT_FORMAT_STORE                 (0x3 << 16)
+#define   CSI_PPA_PAD_LINE_NOPAD                     (0x2 << 24)
+#define   CSI_PP_HEADER_EC_DISABLE                   (0x1 << 27)
+#define   CSI_PPA_PAD_FRAME_NOPAD                    (0x2 << 28)
+
+#define TEGRA_CSI_PIXEL_STREAM_CONTROL1                 0x008
+#define   CSI_PP_TOP_FIELD_FRAME_OFFSET                      0
+#define   CSI_PP_TOP_FIELD_FRAME_MASK_OFFSET         4
+
+#define TEGRA_CSI_PIXEL_STREAM_GAP                      0x00c
+#define   PP_FRAME_MIN_GAP_OFFSET                    16
+
+#define TEGRA_CSI_PIXEL_STREAM_PP_COMMAND               0x010
+#define   CSI_PP_ENABLE                                      0x1
+#define   CSI_PP_DISABLE                             0x2
+#define   CSI_PP_RST                                 0x3
+#define   CSI_PP_SINGLE_SHOT_ENABLE                  (0x1 << 2)
+#define   CSI_PP_START_MARKER_FRAME_MAX_OFFSET               12
+
+#define TEGRA_CSI_PIXEL_STREAM_EXPECTED_FRAME           0x014
+#define TEGRA_CSI_PIXEL_PARSER_INTERRUPT_MASK           0x018
+#define TEGRA_CSI_PIXEL_PARSER_STATUS                   0x01c
+#define TEGRA_CSI_CSI_SW_SENSOR_RESET                   0x020
+
+/* Tegra210 CSI PHY registers */
+/* CSI_PHY_CIL_COMMAND_0 offset 0x0d0 from TEGRA_CSI_PIXEL_PARSER_0_BASE */
+#define TEGRA_CSI_PHY_CIL_COMMAND                       0x0d0
+#define   CSI_A_PHY_CIL_NOP                          0x0
+#define   CSI_A_PHY_CIL_ENABLE                               0x1
+#define   CSI_A_PHY_CIL_DISABLE                              0x2
+#define   CSI_A_PHY_CIL_ENABLE_MASK                  0x3
+#define   CSI_B_PHY_CIL_NOP                          (0x0 << 8)
+#define   CSI_B_PHY_CIL_ENABLE                               (0x1 << 8)
+#define   CSI_B_PHY_CIL_DISABLE                              (0x2 << 8)
+#define   CSI_B_PHY_CIL_ENABLE_MASK                  (0x3 << 8)
+
+#define TEGRA_CSI_CIL_PAD_CONFIG0                       0x000
+#define   BRICK_CLOCK_A_4X                           (0x1 << 16)
+#define   BRICK_CLOCK_B_4X                           (0x2 << 16)
+#define TEGRA_CSI_CIL_PAD_CONFIG1                       0x004
+#define TEGRA_CSI_CIL_PHY_CONTROL                       0x008
+#define TEGRA_CSI_CIL_INTERRUPT_MASK                    0x00c
+#define TEGRA_CSI_CIL_STATUS                            0x010
+#define TEGRA_CSI_CILX_STATUS                           0x014
+#define TEGRA_CSI_CIL_ESCAPE_MODE_COMMAND               0x018
+#define TEGRA_CSI_CIL_ESCAPE_MODE_DATA                  0x01c
+#define TEGRA_CSI_CIL_SW_SENSOR_RESET                   0x020
+
+#define TEGRA_CSI_PATTERN_GENERATOR_CTRL             0x000
+#define   PG_MODE_OFFSET                             2
+#define   PG_ENABLE                                  0x1
+#define   PG_DISABLE                                 0x0
+
+#define PG_VBLANK_OFFSET                             16
+#define TEGRA_CSI_PG_BLANK                           0x004
+#define TEGRA_CSI_PG_PHASE                           0x008
+#define TEGRA_CSI_PG_RED_FREQ                                0x00c
+#define   PG_RED_VERT_INIT_FREQ_OFFSET                       16
+#define   PG_RED_HOR_INIT_FREQ_OFFSET                        0
+
+#define TEGRA_CSI_PG_RED_FREQ_RATE                   0x010
+#define TEGRA_CSI_PG_GREEN_FREQ                              0x014
+#define   PG_GREEN_VERT_INIT_FREQ_OFFSET             16
+#define   PG_GREEN_HOR_INIT_FREQ_OFFSET                      0
+
+#define TEGRA_CSI_PG_GREEN_FREQ_RATE                 0x018
+#define TEGRA_CSI_PG_BLUE_FREQ                               0x01c
+#define   PG_BLUE_VERT_INIT_FREQ_OFFSET                      16
+#define   PG_BLUE_HOR_INIT_FREQ_OFFSET                       0
+
+#define TEGRA_CSI_PG_BLUE_FREQ_RATE                  0x020
+#define TEGRA_CSI_PG_AOHDR                           0x024
+
+#define TEGRA_CSI_DPCM_CTRL_A                                0xa2c
+#define TEGRA_CSI_DPCM_CTRL_B                                0xa30
+
+/* Other CSI registers: Starts from 0xa44, offset 0x20c */
+#define TEGRA_CSI_STALL_COUNTER                              0x20c
+#define TEGRA_CSI_CSI_READONLY_STATUS                        0x210
+#define TEGRA_CSI_CSI_SW_STATUS_RESET                        0x214
+#define TEGRA_CSI_CLKEN_OVERRIDE                     0x218
+#define TEGRA_CSI_DEBUG_CONTROL                              0x21c
+#define TEGRA_CSI_DEBUG_COUNTER_0                    0x220
+#define TEGRA_CSI_DEBUG_COUNTER_1                    0x224
+#define TEGRA_CSI_DEBUG_COUNTER_2                    0x228
+
+/* Tegra210 CSI Pixel Parser registers */
+#define TEGRA_CSI_PIXEL_PARSER_0_BASE                        0x0838
+#define TEGRA_CSI_PIXEL_PARSER_1_BASE                        0x086c
+#define TEGRA_CSI_PIXEL_PARSER_2_BASE                        0x1038
+#define TEGRA_CSI_PIXEL_PARSER_3_BASE                        0x106c
+#define TEGRA_CSI_PIXEL_PARSER_4_BASE                        0x1838
+#define TEGRA_CSI_PIXEL_PARSER_5_BASE                        0x186c
+
+#endif
--
Kind regards,

Sakari Ailus




[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux