On 24/04/18 14:26, Maxime Ripard wrote: > The Cadence CSI-2 RX Controller is an hardware block meant to be used as a > bridge between a CSI-2 bus and pixel grabbers. > > It supports operating with internal or external D-PHY, with up to 4 lanes, > or without any D-PHY. The current code only supports the latter case. > > It also support dynamic mapping of the CSI-2 virtual channels to the > associated pixel grabbers, but that isn't allowed at the moment either. > > Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx> > Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx> > --- > MAINTAINERS | 7 + > drivers/media/platform/Kconfig | 1 + > drivers/media/platform/Makefile | 1 + > drivers/media/platform/cadence/Kconfig | 23 + > drivers/media/platform/cadence/Makefile | 1 + > drivers/media/platform/cadence/cdns-csi2rx.c | 500 +++++++++++++++++++ > 6 files changed, 533 insertions(+) > create mode 100644 drivers/media/platform/cadence/Kconfig > create mode 100644 drivers/media/platform/cadence/Makefile > create mode 100644 drivers/media/platform/cadence/cdns-csi2rx.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 0a1410d5a621..2c27d39611eb 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -3133,6 +3133,13 @@ S: Supported > F: Documentation/filesystems/caching/cachefiles.txt > F: fs/cachefiles/ > > +CADENCE MIPI-CSI2 BRIDGES > +M: Maxime Ripard <maxime.ripard@xxxxxxxxxxx> > +L: linux-media@xxxxxxxxxxxxxxx > +S: Maintained > +F: Documentation/devicetree/bindings/media/cdns,*.txt > +F: drivers/media/platform/cadence/cdns-csi2* > + > CADET FM/AM RADIO RECEIVER DRIVER > M: Hans Verkuil <hverkuil@xxxxxxxxx> > L: linux-media@xxxxxxxxxxxxxxx > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig > index c7a1cf8a1b01..029340ec3da4 100644 > --- a/drivers/media/platform/Kconfig > +++ b/drivers/media/platform/Kconfig > @@ -26,6 +26,7 @@ config VIDEO_VIA_CAMERA > # > # Platform multimedia device configuration > # > +source "drivers/media/platform/cadence/Kconfig" > > source "drivers/media/platform/davinci/Kconfig" > > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile > index 932515df4477..04bc1502a30e 100644 > --- a/drivers/media/platform/Makefile > +++ b/drivers/media/platform/Makefile > @@ -3,6 +3,7 @@ > # Makefile for the video capture/playback device drivers. > # > > +obj-$(CONFIG_VIDEO_CADENCE) += cadence/ > obj-$(CONFIG_VIDEO_VIA_CAMERA) += via-camera.o > obj-$(CONFIG_VIDEO_CAFE_CCIC) += marvell-ccic/ > obj-$(CONFIG_VIDEO_MMP_CAMERA) += marvell-ccic/ > diff --git a/drivers/media/platform/cadence/Kconfig b/drivers/media/platform/cadence/Kconfig > new file mode 100644 > index 000000000000..70c95d79c8f7 > --- /dev/null > +++ b/drivers/media/platform/cadence/Kconfig > @@ -0,0 +1,23 @@ > +config VIDEO_CADENCE > + bool "Cadence Video Devices" > + help > + If you have a media device designed by Cadence, say Y. > + > + Note that this option doesn't include new drivers in the kernel: > + saying N will just cause Kconfig to skip all the questions about > + Cadence media devices. > + > +if VIDEO_CADENCE > + > +config VIDEO_CADENCE_CSI2RX > + tristate "Cadence MIPI-CSI2 RX Controller" > + depends on MEDIA_CONTROLLER > + depends on VIDEO_V4L2_SUBDEV_API > + select V4L2_FWNODE > + help > + Support for the Cadence MIPI CSI2 Receiver controller. > + > + To compile this driver as a module, choose M here: the module will be > + called cdns-csi2rx. > + > +endif > diff --git a/drivers/media/platform/cadence/Makefile b/drivers/media/platform/cadence/Makefile > new file mode 100644 > index 000000000000..99a4086b7448 > --- /dev/null > +++ b/drivers/media/platform/cadence/Makefile > @@ -0,0 +1 @@ > +obj-$(CONFIG_VIDEO_CADENCE_CSI2RX) += cdns-csi2rx.o > diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c > new file mode 100644 > index 000000000000..01f8321c12da > --- /dev/null > +++ b/drivers/media/platform/cadence/cdns-csi2rx.c > @@ -0,0 +1,500 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Driver for Cadence MIPI-CSI2 RX Controller v1.3 > + * > + * Copyright (C) 2017 Cadence Design Systems Inc. > + */ > + > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/io.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_graph.h> > +#include <linux/phy/phy.h> > +#include <linux/platform_device.h> > + > +#include <media/v4l2-ctrls.h> > +#include <media/v4l2-device.h> > +#include <media/v4l2-fwnode.h> > +#include <media/v4l2-subdev.h> > + > +#define CSI2RX_DEVICE_CFG_REG 0x000 > + > +#define CSI2RX_SOFT_RESET_REG 0x004 > +#define CSI2RX_SOFT_RESET_PROTOCOL BIT(1) > +#define CSI2RX_SOFT_RESET_FRONT BIT(0) > + > +#define CSI2RX_STATIC_CFG_REG 0x008 > +#define CSI2RX_STATIC_CFG_DLANE_MAP(llane, plane) ((plane) << (16 + (llane) * 4)) > +#define CSI2RX_STATIC_CFG_LANES_MASK GENMASK(11, 8) > + > +#define CSI2RX_STREAM_BASE(n) (((n) + 1) * 0x100) > + > +#define CSI2RX_STREAM_CTRL_REG(n) (CSI2RX_STREAM_BASE(n) + 0x000) > +#define CSI2RX_STREAM_CTRL_START BIT(0) > + > +#define CSI2RX_STREAM_DATA_CFG_REG(n) (CSI2RX_STREAM_BASE(n) + 0x008) > +#define CSI2RX_STREAM_DATA_CFG_EN_VC_SELECT BIT(31) > +#define CSI2RX_STREAM_DATA_CFG_VC_SELECT(n) BIT((n) + 16) > + > +#define CSI2RX_STREAM_CFG_REG(n) (CSI2RX_STREAM_BASE(n) + 0x00c) > +#define CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF (1 << 8) > + > +#define CSI2RX_LANES_MAX 4 > +#define CSI2RX_STREAMS_MAX 4 > + > +enum csi2rx_pads { > + CSI2RX_PAD_SINK, > + CSI2RX_PAD_SOURCE_STREAM0, > + CSI2RX_PAD_SOURCE_STREAM1, > + CSI2RX_PAD_SOURCE_STREAM2, > + CSI2RX_PAD_SOURCE_STREAM3, > + CSI2RX_PAD_MAX, > +}; > + > +struct csi2rx_priv { > + struct device *dev; > + unsigned int count; > + > + /* > + * Used to prevent race conditions between multiple, > + * concurrent calls to start and stop. > + */ > + struct mutex lock; > + > + void __iomem *base; > + struct clk *sys_clk; > + struct clk *p_clk; > + struct clk *pixel_clk[CSI2RX_STREAMS_MAX]; > + struct phy *dphy; > + > + u8 lanes[CSI2RX_LANES_MAX]; > + u8 num_lanes; > + u8 max_lanes; > + u8 max_streams; > + bool has_internal_dphy; > + > + struct v4l2_subdev subdev; > + struct v4l2_async_notifier notifier; > + struct media_pad pads[CSI2RX_PAD_MAX]; > + > + /* Remote source */ > + struct v4l2_async_subdev asd; > + struct v4l2_subdev *source_subdev; > + int source_pad; > +}; > + > +static inline > +struct csi2rx_priv *v4l2_subdev_to_csi2rx(struct v4l2_subdev *subdev) > +{ > + return container_of(subdev, struct csi2rx_priv, subdev); > +} > + > +static void csi2rx_reset(struct csi2rx_priv *csi2rx) > +{ > + writel(CSI2RX_SOFT_RESET_PROTOCOL | CSI2RX_SOFT_RESET_FRONT, > + csi2rx->base + CSI2RX_SOFT_RESET_REG); > + > + udelay(10); > + > + writel(0, csi2rx->base + CSI2RX_SOFT_RESET_REG); > +} > + > +static int csi2rx_start(struct csi2rx_priv *csi2rx) > +{ > + unsigned int i; > + unsigned long lanes_used = 0; > + u32 reg; > + int ret; > + > + ret = clk_prepare_enable(csi2rx->p_clk); > + if (ret) > + return ret; > + > + csi2rx_reset(csi2rx); > + > + reg = csi2rx->num_lanes << 8; > + for (i = 0; i < csi2rx->num_lanes; i++) { > + reg |= CSI2RX_STATIC_CFG_DLANE_MAP(i, csi2rx->lanes[i]); > + set_bit(csi2rx->lanes[i], &lanes_used); > + } > + > + /* > + * Even the unused lanes need to be mapped. In order to avoid > + * to map twice to the same physical lane, keep the lanes used > + * in the previous loop, and only map unused physical lanes to > + * the rest of our logical lanes. > + */ > + for (i = csi2rx->num_lanes; i < csi2rx->max_lanes; i++) { > + unsigned int idx = find_first_zero_bit(&lanes_used, > + sizeof(lanes_used)); > + set_bit(idx, &lanes_used); > + reg |= CSI2RX_STATIC_CFG_DLANE_MAP(i, i + 1); > + } > + > + writel(reg, csi2rx->base + CSI2RX_STATIC_CFG_REG); > + > + ret = v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, true); > + if (ret) > + goto err_disable_pclk; > + > + /* > + * Create a static mapping between the CSI virtual channels > + * and the output stream. > + * > + * This should be enhanced, but v4l2 lacks the support for > + * changing that mapping dynamically. > + * > + * We also cannot enable and disable independent streams here, > + * hence the reference counting. > + */ > + for (i = 0; i < csi2rx->max_streams; i++) { > + ret = clk_prepare_enable(csi2rx->pixel_clk[i]); > + if (ret) > + goto err_disable_pixclk; > + > + writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF, > + csi2rx->base + CSI2RX_STREAM_CFG_REG(i)); > + > + writel(CSI2RX_STREAM_DATA_CFG_EN_VC_SELECT | > + CSI2RX_STREAM_DATA_CFG_VC_SELECT(i), > + csi2rx->base + CSI2RX_STREAM_DATA_CFG_REG(i)); > + > + writel(CSI2RX_STREAM_CTRL_START, > + csi2rx->base + CSI2RX_STREAM_CTRL_REG(i)); > + } > + > + ret = clk_prepare_enable(csi2rx->sys_clk); > + if (ret) > + goto err_disable_pixclk; > + > + clk_disable_unprepare(csi2rx->p_clk); > + > + return 0; > + > +err_disable_pixclk: > + for (; i >= 0; i--) > + clk_disable_unprepare(csi2rx->pixel_clk[i]); > + > +err_disable_pclk: > + clk_disable_unprepare(csi2rx->p_clk); > + > + return ret; > +} > + > +static int csi2rx_stop(struct csi2rx_priv *csi2rx) > +{ > + unsigned int i; > + > + clk_prepare_enable(csi2rx->p_clk); > + clk_disable_unprepare(csi2rx->sys_clk); > + > + for (i = 0; i < csi2rx->max_streams; i++) { > + writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i)); > + > + clk_disable_unprepare(csi2rx->pixel_clk[i]); > + } > + > + clk_disable_unprepare(csi2rx->p_clk); > + > + return v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false); > +} > + > +static int csi2rx_s_stream(struct v4l2_subdev *subdev, int enable) > +{ > + struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev); > + int ret = 0; > + > + mutex_lock(&csi2rx->lock); > + > + if (enable) { > + /* > + * If we're not the first users, there's no need to > + * enable the whole controller. > + */ > + if (!csi2rx->count) { > + ret = csi2rx_start(csi2rx); > + if (ret) > + goto out; > + } > + > + csi2rx->count++; > + } else { > + csi2rx->count--; > + > + /* > + * Let the last user turn off the lights. > + */ > + if (!csi2rx->count) { > + ret = csi2rx_stop(csi2rx); > + if (ret) > + goto out; Here the error from csi2rx_stop is propagated to the caller, but in the TX driver it is ignored. Is there a reason for the difference? In general I see little value in propagating errors when releasing/stopping something, since there is usually very little you can do to handle the error. It really shouldn't fail. Regards, Hans > + } > + } > + > +out: > + mutex_unlock(&csi2rx->lock); > + return ret; > +} > + > +static const struct v4l2_subdev_video_ops csi2rx_video_ops = { > + .s_stream = csi2rx_s_stream, > +}; > + > +static const struct v4l2_subdev_ops csi2rx_subdev_ops = { > + .video = &csi2rx_video_ops, > +}; > + > +static int csi2rx_async_bound(struct v4l2_async_notifier *notifier, > + struct v4l2_subdev *s_subdev, > + struct v4l2_async_subdev *asd) > +{ > + struct v4l2_subdev *subdev = notifier->sd; > + struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev); > + > + csi2rx->source_pad = media_entity_get_fwnode_pad(&s_subdev->entity, > + s_subdev->fwnode, > + MEDIA_PAD_FL_SOURCE); > + if (csi2rx->source_pad < 0) { > + dev_err(csi2rx->dev, "Couldn't find output pad for subdev %s\n", > + s_subdev->name); > + return csi2rx->source_pad; > + } > + > + csi2rx->source_subdev = s_subdev; > + > + dev_dbg(csi2rx->dev, "Bound %s pad: %d\n", s_subdev->name, > + csi2rx->source_pad); > + > + return media_create_pad_link(&csi2rx->source_subdev->entity, > + csi2rx->source_pad, > + &csi2rx->subdev.entity, 0, > + MEDIA_LNK_FL_ENABLED | > + MEDIA_LNK_FL_IMMUTABLE); > +} > + > +static const struct v4l2_async_notifier_operations csi2rx_notifier_ops = { > + .bound = csi2rx_async_bound, > +}; > + > +static int csi2rx_get_resources(struct csi2rx_priv *csi2rx, > + struct platform_device *pdev) > +{ > + struct resource *res; > + unsigned char i; > + u32 dev_cfg; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + csi2rx->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(csi2rx->base)) > + return PTR_ERR(csi2rx->base); > + > + csi2rx->sys_clk = devm_clk_get(&pdev->dev, "sys_clk"); > + if (IS_ERR(csi2rx->sys_clk)) { > + dev_err(&pdev->dev, "Couldn't get sys clock\n"); > + return PTR_ERR(csi2rx->sys_clk); > + } > + > + csi2rx->p_clk = devm_clk_get(&pdev->dev, "p_clk"); > + if (IS_ERR(csi2rx->p_clk)) { > + dev_err(&pdev->dev, "Couldn't get P clock\n"); > + return PTR_ERR(csi2rx->p_clk); > + } > + > + csi2rx->dphy = devm_phy_optional_get(&pdev->dev, "dphy"); > + if (IS_ERR(csi2rx->dphy)) { > + dev_err(&pdev->dev, "Couldn't get external D-PHY\n"); > + return PTR_ERR(csi2rx->dphy); > + } > + > + /* > + * FIXME: Once we'll have external D-PHY support, the check > + * will need to be removed. > + */ > + if (csi2rx->dphy) { > + dev_err(&pdev->dev, "External D-PHY not supported yet\n"); > + return -EINVAL; > + } > + > + clk_prepare_enable(csi2rx->p_clk); > + dev_cfg = readl(csi2rx->base + CSI2RX_DEVICE_CFG_REG); > + clk_disable_unprepare(csi2rx->p_clk); > + > + csi2rx->max_lanes = dev_cfg & 7; > + if (csi2rx->max_lanes > CSI2RX_LANES_MAX) { > + dev_err(&pdev->dev, "Invalid number of lanes: %u\n", > + csi2rx->max_lanes); > + return -EINVAL; > + } > + > + csi2rx->max_streams = (dev_cfg >> 4) & 7; > + if (csi2rx->max_streams > CSI2RX_STREAMS_MAX) { > + dev_err(&pdev->dev, "Invalid number of streams: %u\n", > + csi2rx->max_streams); > + return -EINVAL; > + } > + > + csi2rx->has_internal_dphy = dev_cfg & BIT(3) ? true : false; > + > + /* > + * FIXME: Once we'll have internal D-PHY support, the check > + * will need to be removed. > + */ > + if (csi2rx->has_internal_dphy) { > + dev_err(&pdev->dev, "Internal D-PHY not supported yet\n"); > + return -EINVAL; > + } > + > + for (i = 0; i < csi2rx->max_streams; i++) { > + char clk_name[16]; > + > + snprintf(clk_name, sizeof(clk_name), "pixel_if%u_clk", i); > + csi2rx->pixel_clk[i] = devm_clk_get(&pdev->dev, clk_name); > + if (IS_ERR(csi2rx->pixel_clk[i])) { > + dev_err(&pdev->dev, "Couldn't get clock %s\n", clk_name); > + return PTR_ERR(csi2rx->pixel_clk[i]); > + } > + } > + > + return 0; > +} > + > +static int csi2rx_parse_dt(struct csi2rx_priv *csi2rx) > +{ > + struct v4l2_fwnode_endpoint v4l2_ep; > + struct fwnode_handle *fwh; > + struct device_node *ep; > + int ret; > + > + ep = of_graph_get_endpoint_by_regs(csi2rx->dev->of_node, 0, 0); > + if (!ep) > + return -EINVAL; > + > + fwh = of_fwnode_handle(ep); > + ret = v4l2_fwnode_endpoint_parse(fwh, &v4l2_ep); > + if (ret) { > + dev_err(csi2rx->dev, "Could not parse v4l2 endpoint\n"); > + of_node_put(ep); > + return ret; > + } > + > + if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) { > + dev_err(csi2rx->dev, "Unsupported media bus type: 0x%x\n", > + v4l2_ep.bus_type); > + of_node_put(ep); > + return -EINVAL; > + } > + > + memcpy(csi2rx->lanes, v4l2_ep.bus.mipi_csi2.data_lanes, > + sizeof(csi2rx->lanes)); > + csi2rx->num_lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes; > + if (csi2rx->num_lanes > csi2rx->max_lanes) { > + dev_err(csi2rx->dev, "Unsupported number of data-lanes: %d\n", > + csi2rx->num_lanes); > + of_node_put(ep); > + return -EINVAL; > + } > + > + csi2rx->asd.match.fwnode = fwnode_graph_get_remote_port_parent(fwh); > + csi2rx->asd.match_type = V4L2_ASYNC_MATCH_FWNODE; > + of_node_put(ep); > + > + csi2rx->notifier.subdevs = devm_kzalloc(csi2rx->dev, > + sizeof(*csi2rx->notifier.subdevs), > + GFP_KERNEL); > + if (!csi2rx->notifier.subdevs) > + return -ENOMEM; > + > + csi2rx->notifier.subdevs[0] = &csi2rx->asd; > + csi2rx->notifier.num_subdevs = 1; > + csi2rx->notifier.ops = &csi2rx_notifier_ops; > + > + return v4l2_async_subdev_notifier_register(&csi2rx->subdev, > + &csi2rx->notifier); > +} > + > +static int csi2rx_probe(struct platform_device *pdev) > +{ > + struct csi2rx_priv *csi2rx; > + unsigned int i; > + int ret; > + > + csi2rx = kzalloc(sizeof(*csi2rx), GFP_KERNEL); > + if (!csi2rx) > + return -ENOMEM; > + platform_set_drvdata(pdev, csi2rx); > + csi2rx->dev = &pdev->dev; > + mutex_init(&csi2rx->lock); > + > + ret = csi2rx_get_resources(csi2rx, pdev); > + if (ret) > + goto err_free_priv; > + > + ret = csi2rx_parse_dt(csi2rx); > + if (ret) > + goto err_free_priv; > + > + csi2rx->subdev.owner = THIS_MODULE; > + csi2rx->subdev.dev = &pdev->dev; > + v4l2_subdev_init(&csi2rx->subdev, &csi2rx_subdev_ops); > + v4l2_set_subdevdata(&csi2rx->subdev, &pdev->dev); > + snprintf(csi2rx->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s.%s", > + KBUILD_MODNAME, dev_name(&pdev->dev)); > + > + /* Create our media pads */ > + csi2rx->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE; > + csi2rx->pads[CSI2RX_PAD_SINK].flags = MEDIA_PAD_FL_SINK; > + for (i = CSI2RX_PAD_SOURCE_STREAM0; i < CSI2RX_PAD_MAX; i++) > + csi2rx->pads[i].flags = MEDIA_PAD_FL_SOURCE; > + > + ret = media_entity_pads_init(&csi2rx->subdev.entity, CSI2RX_PAD_MAX, > + csi2rx->pads); > + if (ret) > + goto err_free_priv; > + > + ret = v4l2_async_register_subdev(&csi2rx->subdev); > + if (ret < 0) > + goto err_free_priv; > + > + dev_info(&pdev->dev, > + "Probed CSI2RX with %u/%u lanes, %u streams, %s D-PHY\n", > + csi2rx->num_lanes, csi2rx->max_lanes, csi2rx->max_streams, > + csi2rx->has_internal_dphy ? "internal" : "no"); > + > + return 0; > + > +err_free_priv: > + kfree(csi2rx); > + return ret; > +} > + > +static int csi2rx_remove(struct platform_device *pdev) > +{ > + struct csi2rx_priv *csi2rx = platform_get_drvdata(pdev); > + > + v4l2_async_unregister_subdev(&csi2rx->subdev); > + kfree(csi2rx); > + > + return 0; > +} > + > +static const struct of_device_id csi2rx_of_table[] = { > + { .compatible = "cdns,csi2rx" }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, csi2rx_of_table); > + > +static struct platform_driver csi2rx_driver = { > + .probe = csi2rx_probe, > + .remove = csi2rx_remove, > + > + .driver = { > + .name = "cdns-csi2rx", > + .of_match_table = csi2rx_of_table, > + }, > +}; > +module_platform_driver(csi2rx_driver); > +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@xxxxxxxxxxx>"); > +MODULE_DESCRIPTION("Cadence CSI2-RX controller"); > +MODULE_LICENSE("GPL"); >