This patch adds raw video support for the Samsung SUR40, now finally using
videobuf2-dma-sg and the usb_sg_init/_wait helper functions. Further comments
regarding buffer handling are invited, as v4l2-compliance -s still fails the
USERPTR test.
Signed-off-by: Florian Echtler <floe@xxxxxxxxxxxxxx>
---
drivers/input/touchscreen/sur40.c | 424 ++++++++++++++++++++++++++++++++++++--
1 file changed, 412 insertions(+), 12 deletions(-)
diff --git a/drivers/input/touchscreen/sur40.c b/drivers/input/touchscreen/sur40.c
index f1cb051..33bc1b8 100644
--- a/drivers/input/touchscreen/sur40.c
+++ b/drivers/input/touchscreen/sur40.c
@@ -1,7 +1,7 @@
/*
* Surface2.0/SUR40/PixelSense input driver
*
- * Copyright (c) 2013 by Florian 'floe' Echtler <floe@xxxxxxxxxxxxxx>
+ * Copyright (c) 2014 by Florian 'floe' Echtler <floe@xxxxxxxxxxxxxx>
*
* Derived from the USB Skeleton driver 1.1,
* Copyright (c) 2003 Greg Kroah-Hartman (greg@xxxxxxxxx)
@@ -12,6 +12,9 @@
* and from the generic hid-multitouch driver,
* Copyright (c) 2010-2012 Stephane Chatty <chatty@xxxxxxx>
*
+ * and from the v4l2-pci-skeleton driver,
+ * Copyright (c) Copyright 2014 Cisco Systems, Inc.
+ *
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
@@ -31,6 +34,11 @@
#include <linux/input-polldev.h>
#include <linux/input/mt.h>
#include <linux/usb/input.h>
+#include <linux/videodev2.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-dma-sg.h>
/* read 512 bytes from endpoint 0x86 -> get header + blobs */
struct sur40_header {
@@ -82,9 +90,19 @@ struct sur40_data {
struct sur40_blob blobs[];
} __packed;
+/* read 512 bytes from endpoint 0x82 -> get header below
+ * continue reading 16k blocks until header.size bytes read */
+struct sur40_image_header {
+ __le32 magic; /* "SUBF" */
+ __le32 packet_id;
+ __le32 size; /* always 0x0007e900 = 960x540 */
+ __le32 timestamp; /* milliseconds (increases by 16 or 17 each frame) */
+ __le32 unknown; /* "epoch?" always 02/03 00 00 00 */
+} __packed;
/* version information */
#define DRIVER_SHORT "sur40"
+#define DRIVER_LONG "Samsung SUR40"
#define DRIVER_AUTHOR "Florian 'floe' Echtler <floe@xxxxxxxxxxxxxx>"
#define DRIVER_DESC "Surface2.0/SUR40/PixelSense input driver"
@@ -99,6 +117,13 @@ struct sur40_data {
/* touch data endpoint */
#define TOUCH_ENDPOINT 0x86
+/* video data endpoint */
+#define VIDEO_ENDPOINT 0x82
+
+/* video header fields */
+#define VIDEO_HEADER_MAGIC 0x46425553
+#define VIDEO_PACKET_SIZE 16384
+
/* polling interval (ms) */
#define POLL_INTERVAL 10
@@ -113,21 +138,23 @@ struct sur40_data {
#define SUR40_GET_STATE 0xc5 /* 4 bytes state (?) */
#define SUR40_GET_SENSORS 0xb1 /* 8 bytes sensors */
-/*
- * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT
- * here by mistake which is very likely to have corrupted the firmware EEPROM
- * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug.
- * Should you ever run into a similar problem, the background story to this
- * incident and instructions on how to fix the corrupted EEPROM are available
- * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html
-*/
-
+/* master device state */
struct sur40_state {
struct usb_device *usbdev;
struct device *dev;
struct input_polled_dev *input;
+ struct v4l2_device v4l2;
+ struct video_device vdev;
+ struct mutex lock;
+
+ struct vb2_queue queue;
+ struct vb2_alloc_ctx *alloc_ctx;
+ struct list_head buf_list;
+ spinlock_t qlock;
+ int sequence;
+
struct sur40_data *bulk_in_buffer;
size_t bulk_in_size;
u8 bulk_in_epaddr;
@@ -135,6 +162,27 @@ struct sur40_state {
char phys[64];
};
+struct sur40_buffer {
+ struct vb2_buffer vb;
+ struct list_head list;
+};
+
+/* forward declarations */
+static const struct video_device sur40_video_device;
+static const struct v4l2_pix_format sur40_video_format;
+static const struct vb2_queue sur40_queue;
+static void sur40_process_video(struct sur40_state *sur40);
+
+/*
+ * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT
+ * here by mistake which is very likely to have corrupted the firmware EEPROM
+ * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug.
+ * Should you ever run into a similar problem, the background story to this
+ * incident and instructions on how to fix the corrupted EEPROM are available
+ * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html
+*/
+
+/* command wrapper */
static int sur40_command(struct sur40_state *dev,
u8 command, u16 index, void *buffer, u16 size)
{
@@ -247,7 +295,6 @@ static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input)
/* core function: poll for new input data */
static void sur40_poll(struct input_polled_dev *polldev)
{
-
struct sur40_state *sur40 = polldev->private;
struct input_dev *input = polldev->input;
int result, bulk_read, need_blobs, packet_blobs, i;
@@ -314,6 +361,81 @@ static void sur40_poll(struct input_polled_dev *polldev)
input_mt_sync_frame(input);
input_sync(input);
+
+ sur40_process_video(sur40);
+}
+
+/* deal with video data */
+static void sur40_process_video(struct sur40_state *sur40)
+{
+
+ struct sur40_image_header *img = (void *)(sur40->bulk_in_buffer);
+ struct sur40_buffer *new_buf;
+ struct usb_sg_request sgr;
+ struct sg_table *sgt;
+ int result, bulk_read;
+
+ if (list_empty(&sur40->buf_list))
+ return;
+
+ /* get a new buffer from the list */
+ spin_lock(&sur40->qlock);
+ new_buf = list_entry(sur40->buf_list.next, struct sur40_buffer, list);
+ list_del(&new_buf->list);
+ spin_unlock(&sur40->qlock);
+
+ /* retrieve data via bulk read */
+ result = usb_bulk_msg(sur40->usbdev,
+ usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT),
+ sur40->bulk_in_buffer, sur40->bulk_in_size,
+ &bulk_read, 1000);
+
+ if (result < 0) {
+ dev_err(sur40->dev, "error in usb_bulk_read\n");
+ goto err_poll;
+ }
+
+ if (bulk_read != sizeof(struct sur40_image_header)) {
+ dev_err(sur40->dev, "received %d bytes (%ld expected)\n",
+ bulk_read, sizeof(struct sur40_image_header));
+ goto err_poll;
+ }
+
+ if (le32_to_cpu(img->magic) != VIDEO_HEADER_MAGIC) {
+ dev_err(sur40->dev, "image magic mismatch\n");
+ goto err_poll;
+ }
+
+ if (le32_to_cpu(img->size) != sur40_video_format.sizeimage) {
+ dev_err(sur40->dev, "image size mismatch\n");
+ goto err_poll;
+ }
+
+ sgt = vb2_dma_sg_plane_desc(&new_buf->vb, 0);
+
+ result = usb_sg_init(&sgr, sur40->usbdev,
+ usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), 0,
+ sgt->sgl, sgt->nents, sur40_video_format.sizeimage, 0);
+ if (result < 0) {
+ dev_err(sur40->dev, "error in usb_sg_init\n");
+ goto err_poll;
+ }
+
+ usb_sg_wait(&sgr);
+ if (sgr.status < 0) {
+ dev_err(sur40->dev, "error in usb_sg_wait\n");
+ goto err_poll;
+ }
+
+ /* mark as finished */
+ v4l2_get_timestamp(&new_buf->vb.v4l2_buf.timestamp);
+ new_buf->vb.v4l2_buf.sequence = sur40->sequence++;
+ new_buf->vb.v4l2_buf.field = V4L2_FIELD_NONE;
+ vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_DONE);
+ return;
+
+err_poll:
+ vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_ERROR);
}
/* Initialize input device parameters. */
@@ -377,6 +499,11 @@ static int sur40_probe(struct usb_interface *interface,
goto err_free_dev;
}
+ /* initialize locks/lists */
+ INIT_LIST_HEAD(&sur40->buf_list);
+ spin_lock_init(&sur40->qlock);
+ mutex_init(&sur40->lock);
+
/* Set up polled input device control structure */
poll_dev->private = sur40;
poll_dev->poll_interval = POLL_INTERVAL;
@@ -387,7 +514,7 @@ static int sur40_probe(struct usb_interface *interface,
/* Set up regular input device structure */
sur40_input_setup(poll_dev->input);
- poll_dev->input->name = "Samsung SUR40";
+ poll_dev->input->name = DRIVER_LONG;
usb_to_input_id(usbdev, &poll_dev->input->id);
usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys));
strlcat(sur40->phys, "/input0", sizeof(sur40->phys));
@@ -408,6 +535,7 @@ static int sur40_probe(struct usb_interface *interface,
goto err_free_polldev;
}
+ /* register the polled input device */
error = input_register_polled_device(poll_dev);
if (error) {
dev_err(&interface->dev,
@@ -415,12 +543,54 @@ static int sur40_probe(struct usb_interface *interface,
goto err_free_buffer;
}
+ /* register the video master device */
+ snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG);
+ error = v4l2_device_register(sur40->dev, &sur40->v4l2);
+ if (error) {
+ dev_err(&interface->dev,
+ "Unable to register video master device.");
+ goto err_unreg_v4l2;
+ }
+
+ /* initialize the lock and subdevice */
+ sur40->queue = sur40_queue;
+ sur40->queue.drv_priv = sur40;
+ sur40->queue.lock = &sur40->lock;
+
+ /* initialize the queue */
+ error = vb2_queue_init(&sur40->queue);
+ if (error)
+ goto err_unreg_v4l2;
+
+ sur40->alloc_ctx = vb2_dma_sg_init_ctx(sur40->dev);
+ if (IS_ERR(sur40->alloc_ctx)) {
+ dev_err(sur40->dev, "Can't allocate buffer context");
+ goto err_unreg_v4l2;
+ }
+
+ sur40->vdev = sur40_video_device;
+ sur40->vdev.v4l2_dev = &sur40->v4l2;
+ sur40->vdev.lock = &sur40->lock;
+ sur40->vdev.queue = &sur40->queue;
+ video_set_drvdata(&sur40->vdev, sur40);
+
+ error = video_register_device(&sur40->vdev, VFL_TYPE_GRABBER, -1);
+ if (error) {
+ dev_err(&interface->dev,
+ "Unable to register video subdevice.");
+ goto err_unreg_video;
+ }
+
/* we can register the device now, as it is ready */
usb_set_intfdata(interface, sur40);
dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC);
return 0;
+err_unreg_video:
+ video_unregister_device(&sur40->vdev);
+err_unreg_v4l2:
+ v4l2_device_unregister(&sur40->v4l2);
err_free_buffer:
kfree(sur40->bulk_in_buffer);
err_free_polldev:
@@ -436,6 +606,10 @@ static void sur40_disconnect(struct usb_interface *interface)
{
struct sur40_state *sur40 = usb_get_intfdata(interface);
+ video_unregister_device(&sur40->vdev);
+ v4l2_device_unregister(&sur40->v4l2);
+ vb2_dma_sg_cleanup_ctx(sur40->alloc_ctx);
+
input_unregister_polled_device(sur40->input);
input_free_polled_device(sur40->input);
kfree(sur40->bulk_in_buffer);
@@ -445,12 +619,238 @@ static void sur40_disconnect(struct usb_interface *interface)
dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC);
}
+/*
+ * Setup the constraints of the queue: besides setting the number of planes
+ * per buffer and the size and allocation context of each plane, it also
+ * checks if sufficient buffers have been allocated. Usually 3 is a good
+ * minimum number: many DMA engines need a minimum of 2 buffers in the
+ * queue and you need to have another available for userspace processing.
+ */
+static int sur40_queue_setup(struct vb2_queue *q, const struct v4l2_format *fmt,
+ unsigned int *nbuffers, unsigned int *nplanes,
+ unsigned int sizes[], void *alloc_ctxs[])
+{
+ struct sur40_state *sur40 = vb2_get_drv_priv(q);
+
+ if (q->num_buffers + *nbuffers < 3)
+ *nbuffers = 3 - q->num_buffers;
+
+ if (fmt && fmt->fmt.pix.sizeimage < sur40_video_format.sizeimage)
+ return -EINVAL;
+
+ *nplanes = 1;
+ sizes[0] = fmt ? fmt->fmt.pix.sizeimage : sur40_video_format.sizeimage;
+ alloc_ctxs[0] = sur40->alloc_ctx;
+
+ return 0;
+}
+
+/*
+ * Prepare the buffer for queueing to the DMA engine: check and set the
+ * payload size.
+ */
+static int sur40_buffer_prepare(struct vb2_buffer *vb)
+{
+ struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue);
+ unsigned long size = sur40_video_format.sizeimage;
+
+ if (vb2_plane_size(vb, 0) < size) {
+ dev_err(&sur40->usbdev->dev, "buffer too small (%lu < %lu)\n",
+ vb2_plane_size(vb, 0), size);
+ return -EINVAL;
+ }
+
+ vb2_set_plane_payload(vb, 0, size);
+ return 0;
+}
+
+/*
+ * Queue this buffer to the DMA engine.
+ */
+static void sur40_buffer_queue(struct vb2_buffer *vb)
+{
+ struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue);
+ struct sur40_buffer *buf = (struct sur40_buffer *)vb;
+
+ spin_lock(&sur40->qlock);
+ list_add_tail(&buf->list, &sur40->buf_list);
+ spin_unlock(&sur40->qlock);
+}
+
+static void return_all_buffers(struct sur40_state *sur40,
+ enum vb2_buffer_state state)
+{
+ struct sur40_buffer *buf, *node;
+
+ spin_lock(&sur40->qlock);
+ list_for_each_entry_safe(buf, node, &sur40->buf_list, list) {
+ vb2_buffer_done(&buf->vb, state);
+ list_del(&buf->list);
+ }
+ spin_unlock(&sur40->qlock);
+}
+
+/*
+ * Start streaming. First check if the minimum number of buffers have been
+ * queued. If not, then return -ENOBUFS and the vb2 framework will call
+ * this function again the next time a buffer has been queued until enough
+ * buffers are available to actually start the DMA engine.
+ */
+static int sur40_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+ struct sur40_state *sur40 = vb2_get_drv_priv(vq);
+
+ sur40->sequence = 0;
+ return 0;
+}
+
+/*
+ * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued
+ * and passed on to the vb2 framework marked as STATE_ERROR.
+ */
+static void sur40_stop_streaming(struct vb2_queue *vq)
+{
+ struct sur40_state *sur40 = vb2_get_drv_priv(vq);
+
+ /* Release all active buffers */
+ return_all_buffers(sur40, VB2_BUF_STATE_ERROR);
+}
+
+/* V4L ioctl */
+static int sur40_vidioc_querycap(struct file *file, void *priv,
+ struct v4l2_capability *cap)
+{
+ struct sur40_state *sur40 = video_drvdata(file);
+
+ strlcpy(cap->driver, DRIVER_SHORT, sizeof(cap->driver));
+ strlcpy(cap->card, DRIVER_LONG, sizeof(cap->card));
+ usb_make_path(sur40->usbdev, cap->bus_info, sizeof(cap->bus_info));
+ cap->device_caps = V4L2_CAP_VIDEO_CAPTURE |
+ V4L2_CAP_READWRITE |
+ V4L2_CAP_STREAMING;
+ cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
+ return 0;
+}
+
+static int sur40_vidioc_enum_input(struct file *file, void *priv,
+ struct v4l2_input *i)
+{
+ if (i->index != 0)
+ return -EINVAL;
+ i->type = V4L2_INPUT_TYPE_CAMERA;
+ i->std = V4L2_STD_UNKNOWN;
+ strlcpy(i->name, "In-Cell Sensor", sizeof(i->name));
+ i->capabilities = 0;
+ return 0;
+}
+
+static int sur40_vidioc_s_input(struct file *file, void *priv, unsigned int i)
+{
+ return (i == 0) ? 0 : -EINVAL;
+}
+
+static int sur40_vidioc_g_input(struct file *file, void *priv, unsigned int *i)
+{
+ *i = 0;
+ return 0;
+}
+
+static int sur40_vidioc_fmt(struct file *file, void *priv,
+ struct v4l2_format *f)
+{
+ f->fmt.pix = sur40_video_format;
+ return 0;
+}
+
+static int sur40_vidioc_enum_fmt(struct file *file, void *priv,
+ struct v4l2_fmtdesc *f)
+{
+ if (f->index != 0)
+ return -EINVAL;
+ strlcpy(f->description, "8-bit greyscale", sizeof(f->description));
+ f->pixelformat = V4L2_PIX_FMT_GREY;
+ f->flags = 0;
+ return 0;
+}
+
static const struct usb_device_id sur40_table[] = {
{ USB_DEVICE(ID_MICROSOFT, ID_SUR40) }, /* Samsung SUR40 */
{ } /* terminating null entry */
};
MODULE_DEVICE_TABLE(usb, sur40_table);
+/* V4L2 structures */
+static const struct vb2_ops sur40_queue_ops = {
+ .queue_setup = sur40_queue_setup,
+ .buf_prepare = sur40_buffer_prepare,
+ .buf_queue = sur40_buffer_queue,
+ .start_streaming = sur40_start_streaming,
+ .stop_streaming = sur40_stop_streaming,
+ .wait_prepare = vb2_ops_wait_prepare,
+ .wait_finish = vb2_ops_wait_finish,
+};
+
+static const struct vb2_queue sur40_queue = {
+ .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
+ .io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF | VB2_USERPTR,
+ .buf_struct_size = sizeof(struct sur40_buffer),
+ .ops = &sur40_queue_ops,
+ .mem_ops = &vb2_dma_sg_memops,
+ .timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC,
+ .min_buffers_needed = 3,
+};
+
+static const struct v4l2_file_operations sur40_video_fops = {
+ .owner = THIS_MODULE,
+ .open = v4l2_fh_open,
+ .release = vb2_fop_release,
+ .unlocked_ioctl = video_ioctl2,
+ .read = vb2_fop_read,
+ .mmap = vb2_fop_mmap,
+ .poll = vb2_fop_poll,
+};
+
+static const struct v4l2_ioctl_ops sur40_video_ioctl_ops = {
+
+ .vidioc_querycap = sur40_vidioc_querycap,
+
+ .vidioc_enum_fmt_vid_cap = sur40_vidioc_enum_fmt,
+ .vidioc_try_fmt_vid_cap = sur40_vidioc_fmt,
+ .vidioc_s_fmt_vid_cap = sur40_vidioc_fmt,
+ .vidioc_g_fmt_vid_cap = sur40_vidioc_fmt,
+
+ .vidioc_enum_input = sur40_vidioc_enum_input,
+ .vidioc_g_input = sur40_vidioc_g_input,
+ .vidioc_s_input = sur40_vidioc_s_input,
+
+ .vidioc_reqbufs = vb2_ioctl_reqbufs,
+ .vidioc_create_bufs = vb2_ioctl_create_bufs,
+ .vidioc_querybuf = vb2_ioctl_querybuf,
+ .vidioc_qbuf = vb2_ioctl_qbuf,
+ .vidioc_dqbuf = vb2_ioctl_dqbuf,
+ .vidioc_expbuf = vb2_ioctl_expbuf,
+
+ .vidioc_streamon = vb2_ioctl_streamon,
+ .vidioc_streamoff = vb2_ioctl_streamoff,
+};
+
+static const struct video_device sur40_video_device = {
+ .name = DRIVER_LONG,
+ .fops = &sur40_video_fops,
+ .ioctl_ops = &sur40_video_ioctl_ops,
+ .release = video_device_release_empty,
+};
+
+static const struct v4l2_pix_format sur40_video_format = {
+ .pixelformat = V4L2_PIX_FMT_GREY,
+ .width = SENSOR_RES_X / 2,
+ .height = SENSOR_RES_Y / 2,
+ .field = V4L2_FIELD_NONE,
+ .colorspace = V4L2_COLORSPACE_SRGB,
+ .bytesperline = SENSOR_RES_X / 2,
+ .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2),
+};
+
/* USB-specific object needed to register this driver with the USB subsystem. */
static struct usb_driver sur40_driver = {
.name = DRIVER_SHORT,
--
1.9.1
--
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