[PATCH v7 0/2] media: video-i2c: add video-i2c driver support

[PATCH v7 0/2] media: video-i2c: add video-i2c driver support

[Matt Ranostay]

Add support for video-i2c polling driver

Changes from v1:
* Switch to SPDX tags versus GPLv2 license text
* Remove unneeded zeroing of data structures
* Add video_i2c_try_fmt_vid_cap call in video_i2c_s_fmt_vid_cap function

Changes from v2:
* Add missing linux/kthread.h include that broke x86_64 build

Changes from v3:
* Add devicetree binding documents
* snprintf check added
* switched to per chip support based on devicetree or i2c client id
* add VB2_DMABUF to io_modes
* added entry to MAINTAINERS file switched to per chip support based on devicetree or i2c client id

Changes from v4:
* convert pointer from of_device_get_match_data() to long instead of int to avoid compiler warning

Changes from v5:
* fix various issues with v4l2-compliance tool run

Changes from v6:
* fixed minor coding issues on spacing
* changed device tree table pointers to chip struct data
* add more verbose Kconfig documentation
* destroy mutexes on error path and module removal
* fixed MODULE_LICENSE from GPL to GPLv2
* changes some calls to list_last_entry() to avoid touching next pointer
* moved common code to a function from start/stop_streaming()

Matt Ranostay (2):
  media: dt-bindings: Add bindings for panasonic,amg88xx
  media: video-i2c: add video-i2c driver

 .../bindings/media/i2c/panasonic,amg88xx.txt       |  19 +
 MAINTAINERS                                        |   6 +
 drivers/media/i2c/Kconfig                          |  13 +
 drivers/media/i2c/Makefile                         |   1 +
 drivers/media/i2c/video-i2c.c                      | 560 +++++++++++++++++++++
 5 files changed, 599 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/i2c/panasonic,amg88xx.txt
 create mode 100644 drivers/media/i2c/video-i2c.c

-- 
2.14.1

[PATCH v7 1/2] media: dt-bindings: Add bindings for panasonic,amg88xx

[Matt Ranostay]

Define the device tree bindings for the panasonic,amg88xx i2c
video driver.

Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
---
 .../bindings/media/i2c/panasonic,amg88xx.txt          | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/i2c/panasonic,amg88xx.txt

diff --git a/Documentation/devicetree/bindings/media/i2c/panasonic,amg88xx.txt b/Documentation/devicetree/bindings/media/i2c/panasonic,amg88xx.txt
new file mode 100644
index 000000000000..4a3181a3dd7e
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/i2c/panasonic,amg88xx.txt
@@ -0,0 +1,19 @@
+* Panasonic AMG88xx
+
+The Panasonic family of AMG88xx Grid-Eye sensors allow recording
+8x8 10Hz video which consists of thermal datapoints
+
+Required Properties:
+ - compatible : Must be "panasonic,amg88xx"
+ - reg : i2c address of the device
+
+Example:
+
+	i2c0@1c22000 {
+		...
+		amg88xx@69 {
+			compatible = "panasonic,amg88xx";
+			reg = <0x69>;
+		};
+		...
+	};
-- 
2.14.1

[PATCH v7 2/2] media: video-i2c: add video-i2c driver

[Matt Ranostay]

There are several thermal sensors that only have a low-speed bus
interface but output valid video data. This patchset enables support
for the AMG88xx "Grid-Eye" sensor family.

Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
---
 MAINTAINERS                   |   6 +
 drivers/media/i2c/Kconfig     |  13 +
 drivers/media/i2c/Makefile    |   1 +
 drivers/media/i2c/video-i2c.c | 560 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 580 insertions(+)
 create mode 100644 drivers/media/i2c/video-i2c.c

diff --git a/MAINTAINERS b/MAINTAINERS
index dc153da22e8a..928b6a862626 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14880,6 +14880,12 @@ L:	linux-media@vger.kernel.org
 S:	Maintained
 F:	drivers/media/platform/video-mux.c
 
+VIDEO I2C POLLING DRIVER
+M:	Matt Ranostay <matt.ranostay@konsulko.com>
+L:	linux-media@vger.kernel.org
+S:	Maintained
+F:	drivers/media/i2c/video-i2c.c
+
 VIDEOBUF2 FRAMEWORK
 M:	Pawel Osciak <pawel@osciak.com>
 M:	Marek Szyprowski <m.szyprowski@samsung.com>
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 541f0d28afd8..faaaceb94832 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -974,6 +974,19 @@ config VIDEO_M52790
 
 	 To compile this driver as a module, choose M here: the
 	 module will be called m52790.
+
+config VIDEO_I2C
+	tristate "I2C transport video support"
+	depends on VIDEO_V4L2 && I2C
+	select VIDEOBUF2_VMALLOC
+	---help---
+	  Enable the I2C transport video support which supports the
+	  following:
+	   * Panasonic AMG88xx Grid-Eye Sensors
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called video-i2c
+
 endmenu
 
 menu "Sensors used on soc_camera driver"
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index ea34aee1a85a..84cc472238ef 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -96,6 +96,7 @@ obj-$(CONFIG_VIDEO_LM3646)	+= lm3646.o
 obj-$(CONFIG_VIDEO_SMIAPP_PLL)	+= smiapp-pll.o
 obj-$(CONFIG_VIDEO_AK881X)		+= ak881x.o
 obj-$(CONFIG_VIDEO_IR_I2C)  += ir-kbd-i2c.o
+obj-$(CONFIG_VIDEO_I2C)		+= video-i2c.o
 obj-$(CONFIG_VIDEO_ML86V7667)	+= ml86v7667.o
 obj-$(CONFIG_VIDEO_OV2659)	+= ov2659.o
 obj-$(CONFIG_VIDEO_TC358743)	+= tc358743.o
diff --git a/drivers/media/i2c/video-i2c.c b/drivers/media/i2c/video-i2c.c
new file mode 100644
index 000000000000..42427a724c00
--- /dev/null
+++ b/drivers/media/i2c/video-i2c.c
@@ -0,0 +1,560 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * video-i2c.c - Support for I2C transport video devices
+ *
+ * Copyright (C) 2018 Matt Ranostay <matt.ranostay@konsulko.com>
+ *
+ * Supported:
+ * - Panasonic AMG88xx Grid-Eye Sensors
+ */
+
+#include <linux/delay.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include <linux/i2c.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_device.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/videodev2.h>
+#include <media/v4l2-common.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-fh.h>
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-v4l2.h>
+#include <media/videobuf2-vmalloc.h>
+
+#define VIDEO_I2C_DRIVER	"video-i2c"
+
+struct video_i2c_chip;
+
+struct video_i2c_buffer {
+	struct vb2_v4l2_buffer vb;
+	struct list_head list;
+};
+
+struct video_i2c_data {
+	struct i2c_client *client;
+	const struct video_i2c_chip *chip;
+	struct mutex lock;
+	spinlock_t slock;
+	unsigned int sequence;
+	struct mutex queue_lock;
+
+	struct v4l2_device v4l2_dev;
+	struct video_device vdev;
+	struct vb2_queue vb_vidq;
+
+	struct task_struct *kthread_vid_cap;
+	struct list_head vid_cap_active;
+};
+
+static struct v4l2_fmtdesc amg88xx_format = {
+	.pixelformat = V4L2_PIX_FMT_Y12,
+};
+
+static struct v4l2_frmsize_discrete amg88xx_size = {
+	.width = 8,
+	.height = 8,
+};
+
+struct video_i2c_chip {
+	/* video dimensions */
+	const struct v4l2_fmtdesc *format;
+	const struct v4l2_frmsize_discrete *size;
+
+	/* max frames per second */
+	unsigned int max_fps;
+
+	/* pixel buffer size */
+	unsigned int buffer_size;
+
+	/* pixel size in bits */
+	unsigned int bpp;
+
+	/* xfer function */
+	int (*xfer)(struct video_i2c_data *data, char *buf);
+};
+
+static int amg88xx_xfer(struct video_i2c_data *data, char *buf)
+{
+	struct i2c_client *client = data->client;
+	struct i2c_msg msg[2];
+	u8 reg = 0x80;
+	int ret;
+
+	msg[0].addr = client->addr;
+	msg[0].flags = 0;
+	msg[0].len = 1;
+	msg[0].buf  = (char *)&reg;
+
+	msg[1].addr = client->addr;
+	msg[1].flags = I2C_M_RD;
+	msg[1].len = data->chip->buffer_size;
+	msg[1].buf = (char *)buf;
+
+	ret = i2c_transfer(client->adapter, msg, 2);
+
+	return (ret == 2) ? 0 : -EIO;
+}
+
+#define AMG88XX		0
+
+static const struct video_i2c_chip video_i2c_chip[] = {
+	[AMG88XX] = {
+		.size		= &amg88xx_size,
+		.format		= &amg88xx_format,
+		.max_fps	= 10,
+		.buffer_size	= 128,
+		.bpp		= 16,
+		.xfer		= &amg88xx_xfer,
+	},
+};
+
+static const struct v4l2_file_operations video_i2c_fops = {
+	.owner		= THIS_MODULE,
+	.open		= v4l2_fh_open,
+	.release	= vb2_fop_release,
+	.poll		= vb2_fop_poll,
+	.read		= vb2_fop_read,
+	.mmap		= vb2_fop_mmap,
+	.unlocked_ioctl = video_ioctl2,
+};
+
+static int queue_setup(struct vb2_queue *vq,
+		       unsigned int *nbuffers, unsigned int *nplanes,
+		       unsigned int sizes[], struct device *alloc_devs[])
+{
+	struct video_i2c_data *data = vb2_get_drv_priv(vq);
+	unsigned int size = data->chip->buffer_size;
+
+	if (vq->num_buffers + *nbuffers < 2)
+		*nbuffers = 2;
+
+	if (*nplanes)
+		return sizes[0] < size ? -EINVAL : 0;
+
+	*nplanes = 1;
+	sizes[0] = size;
+
+	return 0;
+}
+
+static int buffer_prepare(struct vb2_buffer *vb)
+{
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct video_i2c_data *data = vb2_get_drv_priv(vb->vb2_queue);
+	unsigned int size = data->chip->buffer_size;
+
+	if (vb2_plane_size(vb, 0) < size)
+		return -EINVAL;
+
+	vbuf->field = V4L2_FIELD_NONE;
+	vb2_set_plane_payload(vb, 0, size);
+
+	return 0;
+}
+
+static void buffer_queue(struct vb2_buffer *vb)
+{
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct video_i2c_data *data = vb2_get_drv_priv(vb->vb2_queue);
+	struct video_i2c_buffer *buf =
+			container_of(vbuf, struct video_i2c_buffer, vb);
+
+	spin_lock(&data->slock);
+	list_add_tail(&buf->list, &data->vid_cap_active);
+	spin_unlock(&data->slock);
+}
+
+static int video_i2c_thread_vid_cap(void *priv)
+{
+	struct video_i2c_data *data = priv;
+
+	set_freezable();
+
+	do {
+		unsigned long start_jiffies = jiffies;
+		unsigned int delay = msecs_to_jiffies(1000 / data->chip->max_fps);
+		struct video_i2c_buffer *vid_cap_buf = NULL;
+		int schedule_delay;
+
+		try_to_freeze();
+
+		spin_lock(&data->slock);
+
+		if (!list_empty(&data->vid_cap_active)) {
+			vid_cap_buf = list_last_entry(&data->vid_cap_active,
+						 struct video_i2c_buffer, list);
+			list_del(&vid_cap_buf->list);
+		}
+
+		spin_unlock(&data->slock);
+
+		if (vid_cap_buf) {
+			struct vb2_buffer *vb2_buf = &vid_cap_buf->vb.vb2_buf;
+			void *vbuf = vb2_plane_vaddr(vb2_buf, 0);
+			int ret = data->chip->xfer(data, vbuf);
+
+			vb2_buf->timestamp = ktime_get_ns();
+			vid_cap_buf->vb.sequence = data->sequence++;
+			vb2_buffer_done(vb2_buf, ret ?
+					VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
+		}
+
+		schedule_delay = delay - (jiffies - start_jiffies);
+
+		if (time_after(jiffies, start_jiffies + delay))
+			schedule_delay = delay;
+
+		schedule_timeout_interruptible(schedule_delay);
+	} while (!kthread_should_stop());
+
+	return 0;
+}
+
+static void video_i2c_del_list(struct vb2_queue *vq, enum vb2_buffer_state state)
+{
+	struct video_i2c_data *data = vb2_get_drv_priv(vq);
+	struct video_i2c_buffer *buf, *tmp;
+
+	spin_lock(&data->slock);
+
+	list_for_each_entry_safe(buf, tmp, &data->vid_cap_active, list) {
+		list_del(&buf->list);
+		vb2_buffer_done(&buf->vb.vb2_buf, state);
+	}
+
+	spin_unlock(&data->slock);
+}
+
+static int start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct video_i2c_data *data = vb2_get_drv_priv(vq);
+
+	if (data->kthread_vid_cap)
+		return 0;
+
+	data->sequence = 0;
+	data->kthread_vid_cap = kthread_run(video_i2c_thread_vid_cap, data,
+					    "%s-vid-cap", data->v4l2_dev.name);
+	if (!IS_ERR(data->kthread_vid_cap))
+		return 0;
+
+	video_i2c_del_list(vq, VB2_BUF_STATE_QUEUED);
+
+	return PTR_ERR(data->kthread_vid_cap);
+}
+
+static void stop_streaming(struct vb2_queue *vq)
+{
+	struct video_i2c_data *data = vb2_get_drv_priv(vq);
+
+	if (data->kthread_vid_cap == NULL)
+		return;
+
+	kthread_stop(data->kthread_vid_cap);
+	data->kthread_vid_cap = NULL;
+
+	video_i2c_del_list(vq, VB2_BUF_STATE_ERROR);
+}
+
+static struct vb2_ops video_i2c_video_qops = {
+	.queue_setup		= queue_setup,
+	.buf_prepare		= buffer_prepare,
+	.buf_queue		= buffer_queue,
+	.start_streaming	= start_streaming,
+	.stop_streaming		= stop_streaming,
+	.wait_prepare		= vb2_ops_wait_prepare,
+	.wait_finish		= vb2_ops_wait_finish,
+};
+
+static int video_i2c_querycap(struct file *file, void  *priv,
+				struct v4l2_capability *vcap)
+{
+	struct video_i2c_data *data = video_drvdata(file);
+	struct i2c_client *client = data->client;
+
+	strlcpy(vcap->driver, data->v4l2_dev.name, sizeof(vcap->driver));
+	strlcpy(vcap->card, data->vdev.name, sizeof(vcap->card));
+
+	sprintf(vcap->bus_info, "I2C:%d-%d", client->adapter->nr, client->addr);
+	return 0;
+}
+
+static int video_i2c_g_input(struct file *file, void *fh, unsigned int *inp)
+{
+	*inp = 0;
+
+	return 0;
+}
+
+static int video_i2c_s_input(struct file *file, void *fh, unsigned int inp)
+{
+	return (inp > 0) ? -EINVAL : 0;
+}
+
+static int video_i2c_enum_input(struct file *file, void *fh,
+				  struct v4l2_input *vin)
+{
+	if (vin->index > 0)
+		return -EINVAL;
+
+	strlcpy(vin->name, "Camera", sizeof(vin->name));
+
+	vin->type = V4L2_INPUT_TYPE_CAMERA;
+
+	return 0;
+}
+
+static int video_i2c_enum_fmt_vid_cap(struct file *file, void *fh,
+					struct v4l2_fmtdesc *fmt)
+{
+	struct video_i2c_data *data = video_drvdata(file);
+	enum v4l2_buf_type type = fmt->type;
+
+	if (fmt->index > 0)
+		return -EINVAL;
+
+	*fmt = *data->chip->format;
+	fmt->type = type;
+
+	return 0;
+}
+
+static int video_i2c_enum_framesizes(struct file *file, void *fh,
+				       struct v4l2_frmsizeenum *fsize)
+{
+	const struct video_i2c_data *data = video_drvdata(file);
+	const struct v4l2_frmsize_discrete *size = data->chip->size;
+
+	/* currently only one frame size is allowed */
+	if (fsize->index > 0)
+		return -EINVAL;
+
+	if (fsize->pixel_format != data->chip->format->pixelformat)
+		return -EINVAL;
+
+	fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
+	fsize->discrete.width = size->width;
+	fsize->discrete.height = size->height;
+
+	return 0;
+}
+
+static int video_i2c_enum_frameintervals(struct file *file, void *priv,
+					   struct v4l2_frmivalenum *fe)
+{
+	const struct video_i2c_data *data = video_drvdata(file);
+	const struct v4l2_frmsize_discrete *size = data->chip->size;
+
+	if (fe->index > 0)
+		return -EINVAL;
+
+	if (fe->width != size->width || fe->height != size->height)
+		return -EINVAL;
+
+	fe->type = V4L2_FRMIVAL_TYPE_DISCRETE;
+	fe->discrete.numerator = 1;
+	fe->discrete.denominator = data->chip->max_fps;
+
+	return 0;
+}
+
+static int video_i2c_try_fmt_vid_cap(struct file *file, void *fh,
+				       struct v4l2_format *fmt)
+{
+	const struct video_i2c_data *data = video_drvdata(file);
+	const struct v4l2_frmsize_discrete *size = data->chip->size;
+	struct v4l2_pix_format *pix = &fmt->fmt.pix;
+	unsigned int bpp = data->chip->bpp / 8;
+
+	pix->width = size->width;
+	pix->height = size->height;
+	pix->pixelformat = data->chip->format->pixelformat;
+	pix->field = V4L2_FIELD_NONE;
+	pix->bytesperline = pix->width * bpp;
+	pix->sizeimage = pix->bytesperline * pix->height;
+	pix->colorspace = V4L2_COLORSPACE_RAW;
+
+	return 0;
+}
+
+static int video_i2c_s_fmt_vid_cap(struct file *file, void *fh,
+				     struct v4l2_format *fmt)
+{
+	struct video_i2c_data *data = video_drvdata(file);
+
+	if (vb2_is_busy(&data->vb_vidq))
+		return -EBUSY;
+
+	return video_i2c_try_fmt_vid_cap(file, fh, fmt);
+}
+
+static int video_i2c_g_parm(struct file *filp, void *priv,
+			      struct v4l2_streamparm *parm)
+{
+	struct video_i2c_data *data = video_drvdata(filp);
+
+	if (parm->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+		return -EINVAL;
+
+	parm->parm.capture.readbuffers = 1;
+	parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
+	parm->parm.capture.timeperframe.numerator = 1;
+	parm->parm.capture.timeperframe.denominator = data->chip->max_fps;
+
+	return 0;
+}
+
+static const struct v4l2_ioctl_ops video_i2c_ioctl_ops = {
+	.vidioc_querycap		= video_i2c_querycap,
+	.vidioc_g_input			= video_i2c_g_input,
+	.vidioc_s_input			= video_i2c_s_input,
+	.vidioc_enum_input		= video_i2c_enum_input,
+	.vidioc_enum_fmt_vid_cap	= video_i2c_enum_fmt_vid_cap,
+	.vidioc_enum_framesizes		= video_i2c_enum_framesizes,
+	.vidioc_enum_frameintervals	= video_i2c_enum_frameintervals,
+	.vidioc_g_fmt_vid_cap		= video_i2c_try_fmt_vid_cap,
+	.vidioc_s_fmt_vid_cap		= video_i2c_s_fmt_vid_cap,
+	.vidioc_g_parm			= video_i2c_g_parm,
+	.vidioc_s_parm			= video_i2c_g_parm,
+	.vidioc_try_fmt_vid_cap		= video_i2c_try_fmt_vid_cap,
+	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
+	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
+	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
+	.vidioc_querybuf		= vb2_ioctl_querybuf,
+	.vidioc_qbuf			= vb2_ioctl_qbuf,
+	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
+	.vidioc_streamon		= vb2_ioctl_streamon,
+	.vidioc_streamoff		= vb2_ioctl_streamoff,
+};
+
+static void video_i2c_release(struct video_device *vdev)
+{
+	kfree(video_get_drvdata(vdev));
+}
+
+static int video_i2c_probe(struct i2c_client *client,
+			     const struct i2c_device_id *id)
+{
+	struct video_i2c_data *data;
+	struct v4l2_device *v4l2_dev;
+	struct vb2_queue *queue;
+	int ret;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	if (client->dev.of_node)
+		data->chip = device_get_match_data(&client->dev);
+	else
+		data->chip = &video_i2c_chip[id->driver_data];
+
+	data->client = client;
+	v4l2_dev = &data->v4l2_dev;
+	strlcpy(v4l2_dev->name, VIDEO_I2C_DRIVER, sizeof(v4l2_dev->name));
+
+	ret = v4l2_device_register(&client->dev, v4l2_dev);
+	if (ret < 0)
+		goto error_free_device;
+
+	mutex_init(&data->lock);
+	mutex_init(&data->queue_lock);
+
+	queue = &data->vb_vidq;
+	queue->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	queue->io_modes = VB2_DMABUF | VB2_MMAP | VB2_USERPTR | VB2_READ;
+	queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+	queue->drv_priv = data;
+	queue->buf_struct_size = sizeof(struct video_i2c_buffer);
+	queue->min_buffers_needed = 1;
+	queue->ops = &video_i2c_video_qops;
+	queue->mem_ops = &vb2_vmalloc_memops;
+
+	ret = vb2_queue_init(queue);
+	if (ret < 0)
+		goto error_unregister_device;
+
+	data->vdev.queue = queue;
+	data->vdev.queue->lock = &data->queue_lock;
+
+	snprintf(data->vdev.name, sizeof(data->vdev.name),
+				 "I2C %d-%d Transport Video",
+				 client->adapter->nr, client->addr);
+
+	data->vdev.v4l2_dev = v4l2_dev;
+	data->vdev.fops = &video_i2c_fops;
+	data->vdev.lock = &data->lock;
+	data->vdev.ioctl_ops = &video_i2c_ioctl_ops;
+	data->vdev.release = video_i2c_release;
+	data->vdev.device_caps = V4L2_CAP_VIDEO_CAPTURE |
+				 V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
+
+	spin_lock_init(&data->slock);
+	INIT_LIST_HEAD(&data->vid_cap_active);
+
+	video_set_drvdata(&data->vdev, data);
+	i2c_set_clientdata(client, data);
+
+	ret = video_register_device(&data->vdev, VFL_TYPE_GRABBER, -1);
+	if (ret < 0)
+		goto error_unregister_device;
+
+	return 0;
+
+error_unregister_device:
+	v4l2_device_unregister(v4l2_dev);
+	mutex_destroy(&data->lock);
+	mutex_destroy(&data->queue_lock);
+
+error_free_device:
+	kfree(data);
+
+	return ret;
+}
+
+static int video_i2c_remove(struct i2c_client *client)
+{
+	struct video_i2c_data *data = i2c_get_clientdata(client);
+
+	video_unregister_device(&data->vdev);
+	v4l2_device_unregister(&data->v4l2_dev);
+
+	mutex_destroy(&data->lock);
+	mutex_destroy(&data->queue_lock);
+
+	return 0;
+}
+
+static const struct i2c_device_id video_i2c_id_table[] = {
+	{ "amg88xx", AMG88XX },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, video_i2c_id_table);
+
+static const struct of_device_id video_i2c_of_match[] = {
+	{ .compatible = "panasonic,amg88xx", .data = &video_i2c_chip[AMG88XX] },
+	{}
+};
+MODULE_DEVICE_TABLE(of, video_i2c_of_match);
+
+static struct i2c_driver video_i2c_driver = {
+	.driver = {
+		.name	= VIDEO_I2C_DRIVER,
+		.of_match_table = video_i2c_of_match,
+	},
+	.probe		= video_i2c_probe,
+	.remove		= video_i2c_remove,
+	.id_table	= video_i2c_id_table,
+};
+
+module_i2c_driver(video_i2c_driver);
+
+MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
+MODULE_DESCRIPTION("I2C transport video support");
+MODULE_LICENSE("GPL v2");
-- 
2.14.1

Re: [PATCH v7 2/2] media: video-i2c: add video-i2c driver

[Sakari Ailus]

Hi Matt,

Thanks for the update. A few minor bits, please see below.

On Thu, Apr 05, 2018 at 10:14:49PM -0700, Matt Ranostay wrote:
> There are several thermal sensors that only have a low-speed bus
> interface but output valid video data. This patchset enables support
> for the AMG88xx "Grid-Eye" sensor family.
> 
> Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
> ---
>  MAINTAINERS                   |   6 +
>  drivers/media/i2c/Kconfig     |  13 +
>  drivers/media/i2c/Makefile    |   1 +
>  drivers/media/i2c/video-i2c.c | 560 ++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 580 insertions(+)
>  create mode 100644 drivers/media/i2c/video-i2c.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index dc153da22e8a..928b6a862626 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -14880,6 +14880,12 @@ L:	linux-media@vger.kernel.org
>  S:	Maintained
>  F:	drivers/media/platform/video-mux.c
>  
> +VIDEO I2C POLLING DRIVER
> +M:	Matt Ranostay <matt.ranostay@konsulko.com>
> +L:	linux-media@vger.kernel.org
> +S:	Maintained
> +F:	drivers/media/i2c/video-i2c.c
> +
>  VIDEOBUF2 FRAMEWORK
>  M:	Pawel Osciak <pawel@osciak.com>
>  M:	Marek Szyprowski <m.szyprowski@samsung.com>
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 541f0d28afd8..faaaceb94832 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -974,6 +974,19 @@ config VIDEO_M52790
>  
>  	 To compile this driver as a module, choose M here: the
>  	 module will be called m52790.
> +
> +config VIDEO_I2C
> +	tristate "I2C transport video support"
> +	depends on VIDEO_V4L2 && I2C
> +	select VIDEOBUF2_VMALLOC
> +	---help---
> +	  Enable the I2C transport video support which supports the
> +	  following:
> +	   * Panasonic AMG88xx Grid-Eye Sensors
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called video-i2c
> +
>  endmenu
>  
>  menu "Sensors used on soc_camera driver"
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index ea34aee1a85a..84cc472238ef 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -96,6 +96,7 @@ obj-$(CONFIG_VIDEO_LM3646)	+= lm3646.o
>  obj-$(CONFIG_VIDEO_SMIAPP_PLL)	+= smiapp-pll.o
>  obj-$(CONFIG_VIDEO_AK881X)		+= ak881x.o
>  obj-$(CONFIG_VIDEO_IR_I2C)  += ir-kbd-i2c.o
> +obj-$(CONFIG_VIDEO_I2C)		+= video-i2c.o
>  obj-$(CONFIG_VIDEO_ML86V7667)	+= ml86v7667.o
>  obj-$(CONFIG_VIDEO_OV2659)	+= ov2659.o
>  obj-$(CONFIG_VIDEO_TC358743)	+= tc358743.o
> diff --git a/drivers/media/i2c/video-i2c.c b/drivers/media/i2c/video-i2c.c
> new file mode 100644
> index 000000000000..42427a724c00
> --- /dev/null
> +++ b/drivers/media/i2c/video-i2c.c
> @@ -0,0 +1,560 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * video-i2c.c - Support for I2C transport video devices
> + *
> + * Copyright (C) 2018 Matt Ranostay <matt.ranostay@konsulko.com>
> + *
> + * Supported:
> + * - Panasonic AMG88xx Grid-Eye Sensors
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/freezer.h>
> +#include <linux/kthread.h>
> +#include <linux/i2c.h>
> +#include <linux/list.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of_device.h>
> +#include <linux/sched.h>
> +#include <linux/slab.h>
> +#include <linux/videodev2.h>
> +#include <media/v4l2-common.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-fh.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/videobuf2-v4l2.h>
> +#include <media/videobuf2-vmalloc.h>
> +
> +#define VIDEO_I2C_DRIVER	"video-i2c"
> +
> +struct video_i2c_chip;
> +
> +struct video_i2c_buffer {
> +	struct vb2_v4l2_buffer vb;
> +	struct list_head list;
> +};
> +
> +struct video_i2c_data {
> +	struct i2c_client *client;
> +	const struct video_i2c_chip *chip;
> +	struct mutex lock;
> +	spinlock_t slock;
> +	unsigned int sequence;
> +	struct mutex queue_lock;
> +
> +	struct v4l2_device v4l2_dev;
> +	struct video_device vdev;
> +	struct vb2_queue vb_vidq;
> +
> +	struct task_struct *kthread_vid_cap;
> +	struct list_head vid_cap_active;
> +};
> +
> +static struct v4l2_fmtdesc amg88xx_format = {

const?

> +	.pixelformat = V4L2_PIX_FMT_Y12,
> +};
> +
> +static struct v4l2_frmsize_discrete amg88xx_size = {

const?

> +	.width = 8,
> +	.height = 8,
> +};
> +
> +struct video_i2c_chip {
> +	/* video dimensions */
> +	const struct v4l2_fmtdesc *format;
> +	const struct v4l2_frmsize_discrete *size;
> +
> +	/* max frames per second */
> +	unsigned int max_fps;
> +
> +	/* pixel buffer size */
> +	unsigned int buffer_size;
> +
> +	/* pixel size in bits */
> +	unsigned int bpp;
> +
> +	/* xfer function */
> +	int (*xfer)(struct video_i2c_data *data, char *buf);
> +};
> +
> +static int amg88xx_xfer(struct video_i2c_data *data, char *buf)
> +{
> +	struct i2c_client *client = data->client;
> +	struct i2c_msg msg[2];
> +	u8 reg = 0x80;
> +	int ret;
> +
> +	msg[0].addr = client->addr;
> +	msg[0].flags = 0;
> +	msg[0].len = 1;
> +	msg[0].buf  = (char *)&reg;
> +
> +	msg[1].addr = client->addr;
> +	msg[1].flags = I2C_M_RD;
> +	msg[1].len = data->chip->buffer_size;
> +	msg[1].buf = (char *)buf;
> +
> +	ret = i2c_transfer(client->adapter, msg, 2);
> +
> +	return (ret == 2) ? 0 : -EIO;
> +}
> +
> +#define AMG88XX		0
> +
> +static const struct video_i2c_chip video_i2c_chip[] = {
> +	[AMG88XX] = {
> +		.size		= &amg88xx_size,
> +		.format		= &amg88xx_format,
> +		.max_fps	= 10,
> +		.buffer_size	= 128,
> +		.bpp		= 16,
> +		.xfer		= &amg88xx_xfer,
> +	},
> +};
> +
> +static const struct v4l2_file_operations video_i2c_fops = {
> +	.owner		= THIS_MODULE,
> +	.open		= v4l2_fh_open,
> +	.release	= vb2_fop_release,
> +	.poll		= vb2_fop_poll,
> +	.read		= vb2_fop_read,
> +	.mmap		= vb2_fop_mmap,
> +	.unlocked_ioctl = video_ioctl2,
> +};
> +
> +static int queue_setup(struct vb2_queue *vq,
> +		       unsigned int *nbuffers, unsigned int *nplanes,
> +		       unsigned int sizes[], struct device *alloc_devs[])
> +{
> +	struct video_i2c_data *data = vb2_get_drv_priv(vq);
> +	unsigned int size = data->chip->buffer_size;
> +
> +	if (vq->num_buffers + *nbuffers < 2)
> +		*nbuffers = 2;
> +
> +	if (*nplanes)
> +		return sizes[0] < size ? -EINVAL : 0;
> +
> +	*nplanes = 1;
> +	sizes[0] = size;
> +
> +	return 0;
> +}
> +
> +static int buffer_prepare(struct vb2_buffer *vb)
> +{
> +	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> +	struct video_i2c_data *data = vb2_get_drv_priv(vb->vb2_queue);
> +	unsigned int size = data->chip->buffer_size;
> +
> +	if (vb2_plane_size(vb, 0) < size)
> +		return -EINVAL;
> +
> +	vbuf->field = V4L2_FIELD_NONE;
> +	vb2_set_plane_payload(vb, 0, size);
> +
> +	return 0;
> +}
> +
> +static void buffer_queue(struct vb2_buffer *vb)
> +{
> +	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> +	struct video_i2c_data *data = vb2_get_drv_priv(vb->vb2_queue);
> +	struct video_i2c_buffer *buf =
> +			container_of(vbuf, struct video_i2c_buffer, vb);
> +
> +	spin_lock(&data->slock);
> +	list_add_tail(&buf->list, &data->vid_cap_active);
> +	spin_unlock(&data->slock);
> +}
> +
> +static int video_i2c_thread_vid_cap(void *priv)
> +{
> +	struct video_i2c_data *data = priv;
> +
> +	set_freezable();
> +
> +	do {
> +		unsigned long start_jiffies = jiffies;
> +		unsigned int delay = msecs_to_jiffies(1000 / data->chip->max_fps);
> +		struct video_i2c_buffer *vid_cap_buf = NULL;
> +		int schedule_delay;
> +
> +		try_to_freeze();
> +
> +		spin_lock(&data->slock);
> +
> +		if (!list_empty(&data->vid_cap_active)) {
> +			vid_cap_buf = list_last_entry(&data->vid_cap_active,
> +						 struct video_i2c_buffer, list);
> +			list_del(&vid_cap_buf->list);
> +		}
> +
> +		spin_unlock(&data->slock);
> +
> +		if (vid_cap_buf) {
> +			struct vb2_buffer *vb2_buf = &vid_cap_buf->vb.vb2_buf;
> +			void *vbuf = vb2_plane_vaddr(vb2_buf, 0);
> +			int ret = data->chip->xfer(data, vbuf);
> +
> +			vb2_buf->timestamp = ktime_get_ns();
> +			vid_cap_buf->vb.sequence = data->sequence++;
> +			vb2_buffer_done(vb2_buf, ret ?
> +					VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);

Over 80 characters per lines; please wrap. The same in assignment in delay
declaration above. As max_fps is constant for a given chip, you could just
declare it outside the loop.

> +		}
> +
> +		schedule_delay = delay - (jiffies - start_jiffies);
> +
> +		if (time_after(jiffies, start_jiffies + delay))
> +			schedule_delay = delay;
> +
> +		schedule_timeout_interruptible(schedule_delay);
> +	} while (!kthread_should_stop());
> +
> +	return 0;
> +}
> +
> +static void video_i2c_del_list(struct vb2_queue *vq, enum vb2_buffer_state state)
> +{
> +	struct video_i2c_data *data = vb2_get_drv_priv(vq);
> +	struct video_i2c_buffer *buf, *tmp;
> +
> +	spin_lock(&data->slock);
> +
> +	list_for_each_entry_safe(buf, tmp, &data->vid_cap_active, list) {
> +		list_del(&buf->list);
> +		vb2_buffer_done(&buf->vb.vb2_buf, state);
> +	}
> +
> +	spin_unlock(&data->slock);
> +}
> +
> +static int start_streaming(struct vb2_queue *vq, unsigned int count)
> +{
> +	struct video_i2c_data *data = vb2_get_drv_priv(vq);
> +
> +	if (data->kthread_vid_cap)
> +		return 0;
> +
> +	data->sequence = 0;
> +	data->kthread_vid_cap = kthread_run(video_i2c_thread_vid_cap, data,
> +					    "%s-vid-cap", data->v4l2_dev.name);
> +	if (!IS_ERR(data->kthread_vid_cap))
> +		return 0;
> +
> +	video_i2c_del_list(vq, VB2_BUF_STATE_QUEUED);
> +
> +	return PTR_ERR(data->kthread_vid_cap);
> +}
> +
> +static void stop_streaming(struct vb2_queue *vq)
> +{
> +	struct video_i2c_data *data = vb2_get_drv_priv(vq);
> +
> +	if (data->kthread_vid_cap == NULL)
> +		return;
> +
> +	kthread_stop(data->kthread_vid_cap);
> +	data->kthread_vid_cap = NULL;
> +
> +	video_i2c_del_list(vq, VB2_BUF_STATE_ERROR);
> +}
> +
> +static struct vb2_ops video_i2c_video_qops = {
> +	.queue_setup		= queue_setup,
> +	.buf_prepare		= buffer_prepare,
> +	.buf_queue		= buffer_queue,
> +	.start_streaming	= start_streaming,
> +	.stop_streaming		= stop_streaming,
> +	.wait_prepare		= vb2_ops_wait_prepare,
> +	.wait_finish		= vb2_ops_wait_finish,
> +};
> +
> +static int video_i2c_querycap(struct file *file, void  *priv,
> +				struct v4l2_capability *vcap)
> +{
> +	struct video_i2c_data *data = video_drvdata(file);
> +	struct i2c_client *client = data->client;
> +
> +	strlcpy(vcap->driver, data->v4l2_dev.name, sizeof(vcap->driver));
> +	strlcpy(vcap->card, data->vdev.name, sizeof(vcap->card));
> +
> +	sprintf(vcap->bus_info, "I2C:%d-%d", client->adapter->nr, client->addr);

Newline here.

> +	return 0;
> +}
> +
> +static int video_i2c_g_input(struct file *file, void *fh, unsigned int *inp)
> +{
> +	*inp = 0;
> +
> +	return 0;
> +}
> +
> +static int video_i2c_s_input(struct file *file, void *fh, unsigned int inp)
> +{
> +	return (inp > 0) ? -EINVAL : 0;
> +}
> +
> +static int video_i2c_enum_input(struct file *file, void *fh,
> +				  struct v4l2_input *vin)
> +{
> +	if (vin->index > 0)
> +		return -EINVAL;
> +
> +	strlcpy(vin->name, "Camera", sizeof(vin->name));
> +
> +	vin->type = V4L2_INPUT_TYPE_CAMERA;
> +
> +	return 0;
> +}
> +
> +static int video_i2c_enum_fmt_vid_cap(struct file *file, void *fh,
> +					struct v4l2_fmtdesc *fmt)
> +{
> +	struct video_i2c_data *data = video_drvdata(file);
> +	enum v4l2_buf_type type = fmt->type;
> +
> +	if (fmt->index > 0)
> +		return -EINVAL;
> +
> +	*fmt = *data->chip->format;
> +	fmt->type = type;
> +
> +	return 0;
> +}
> +
> +static int video_i2c_enum_framesizes(struct file *file, void *fh,
> +				       struct v4l2_frmsizeenum *fsize)
> +{
> +	const struct video_i2c_data *data = video_drvdata(file);
> +	const struct v4l2_frmsize_discrete *size = data->chip->size;
> +
> +	/* currently only one frame size is allowed */
> +	if (fsize->index > 0)
> +		return -EINVAL;
> +
> +	if (fsize->pixel_format != data->chip->format->pixelformat)
> +		return -EINVAL;
> +
> +	fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
> +	fsize->discrete.width = size->width;
> +	fsize->discrete.height = size->height;
> +
> +	return 0;
> +}
> +
> +static int video_i2c_enum_frameintervals(struct file *file, void *priv,
> +					   struct v4l2_frmivalenum *fe)
> +{
> +	const struct video_i2c_data *data = video_drvdata(file);
> +	const struct v4l2_frmsize_discrete *size = data->chip->size;
> +
> +	if (fe->index > 0)
> +		return -EINVAL;
> +
> +	if (fe->width != size->width || fe->height != size->height)
> +		return -EINVAL;
> +
> +	fe->type = V4L2_FRMIVAL_TYPE_DISCRETE;
> +	fe->discrete.numerator = 1;
> +	fe->discrete.denominator = data->chip->max_fps;
> +
> +	return 0;
> +}
> +
> +static int video_i2c_try_fmt_vid_cap(struct file *file, void *fh,
> +				       struct v4l2_format *fmt)
> +{
> +	const struct video_i2c_data *data = video_drvdata(file);
> +	const struct v4l2_frmsize_discrete *size = data->chip->size;
> +	struct v4l2_pix_format *pix = &fmt->fmt.pix;
> +	unsigned int bpp = data->chip->bpp / 8;
> +
> +	pix->width = size->width;
> +	pix->height = size->height;
> +	pix->pixelformat = data->chip->format->pixelformat;
> +	pix->field = V4L2_FIELD_NONE;
> +	pix->bytesperline = pix->width * bpp;
> +	pix->sizeimage = pix->bytesperline * pix->height;
> +	pix->colorspace = V4L2_COLORSPACE_RAW;
> +
> +	return 0;
> +}
> +
> +static int video_i2c_s_fmt_vid_cap(struct file *file, void *fh,
> +				     struct v4l2_format *fmt)
> +{
> +	struct video_i2c_data *data = video_drvdata(file);
> +
> +	if (vb2_is_busy(&data->vb_vidq))
> +		return -EBUSY;
> +
> +	return video_i2c_try_fmt_vid_cap(file, fh, fmt);
> +}
> +
> +static int video_i2c_g_parm(struct file *filp, void *priv,
> +			      struct v4l2_streamparm *parm)
> +{
> +	struct video_i2c_data *data = video_drvdata(filp);
> +
> +	if (parm->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
> +		return -EINVAL;
> +
> +	parm->parm.capture.readbuffers = 1;
> +	parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
> +	parm->parm.capture.timeperframe.numerator = 1;
> +	parm->parm.capture.timeperframe.denominator = data->chip->max_fps;
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_ioctl_ops video_i2c_ioctl_ops = {
> +	.vidioc_querycap		= video_i2c_querycap,
> +	.vidioc_g_input			= video_i2c_g_input,
> +	.vidioc_s_input			= video_i2c_s_input,
> +	.vidioc_enum_input		= video_i2c_enum_input,
> +	.vidioc_enum_fmt_vid_cap	= video_i2c_enum_fmt_vid_cap,
> +	.vidioc_enum_framesizes		= video_i2c_enum_framesizes,
> +	.vidioc_enum_frameintervals	= video_i2c_enum_frameintervals,
> +	.vidioc_g_fmt_vid_cap		= video_i2c_try_fmt_vid_cap,
> +	.vidioc_s_fmt_vid_cap		= video_i2c_s_fmt_vid_cap,
> +	.vidioc_g_parm			= video_i2c_g_parm,
> +	.vidioc_s_parm			= video_i2c_g_parm,
> +	.vidioc_try_fmt_vid_cap		= video_i2c_try_fmt_vid_cap,
> +	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
> +	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
> +	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
> +	.vidioc_querybuf		= vb2_ioctl_querybuf,
> +	.vidioc_qbuf			= vb2_ioctl_qbuf,
> +	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
> +	.vidioc_streamon		= vb2_ioctl_streamon,
> +	.vidioc_streamoff		= vb2_ioctl_streamoff,
> +};
> +
> +static void video_i2c_release(struct video_device *vdev)
> +{
> +	kfree(video_get_drvdata(vdev));
> +}
> +
> +static int video_i2c_probe(struct i2c_client *client,
> +			     const struct i2c_device_id *id)
> +{
> +	struct video_i2c_data *data;
> +	struct v4l2_device *v4l2_dev;
> +	struct vb2_queue *queue;
> +	int ret;
> +
> +	data = kzalloc(sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	if (client->dev.of_node)

If you want to check here (indeed it probably makes sense), then please use
dev_fwnode(&client->dev) instead. With this change, you get ACPI support
effectively for free.

> +		data->chip = device_get_match_data(&client->dev);
> +	else
> +		data->chip = &video_i2c_chip[id->driver_data];

id is NULL if no matching chip ID was found. Could you add a check for it?

> +
> +	data->client = client;
> +	v4l2_dev = &data->v4l2_dev;
> +	strlcpy(v4l2_dev->name, VIDEO_I2C_DRIVER, sizeof(v4l2_dev->name));
> +
> +	ret = v4l2_device_register(&client->dev, v4l2_dev);
> +	if (ret < 0)
> +		goto error_free_device;
> +
> +	mutex_init(&data->lock);
> +	mutex_init(&data->queue_lock);
> +
> +	queue = &data->vb_vidq;
> +	queue->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> +	queue->io_modes = VB2_DMABUF | VB2_MMAP | VB2_USERPTR | VB2_READ;
> +	queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> +	queue->drv_priv = data;
> +	queue->buf_struct_size = sizeof(struct video_i2c_buffer);
> +	queue->min_buffers_needed = 1;
> +	queue->ops = &video_i2c_video_qops;
> +	queue->mem_ops = &vb2_vmalloc_memops;
> +
> +	ret = vb2_queue_init(queue);
> +	if (ret < 0)
> +		goto error_unregister_device;
> +
> +	data->vdev.queue = queue;
> +	data->vdev.queue->lock = &data->queue_lock;
> +
> +	snprintf(data->vdev.name, sizeof(data->vdev.name),
> +				 "I2C %d-%d Transport Video",
> +				 client->adapter->nr, client->addr);
> +
> +	data->vdev.v4l2_dev = v4l2_dev;
> +	data->vdev.fops = &video_i2c_fops;
> +	data->vdev.lock = &data->lock;
> +	data->vdev.ioctl_ops = &video_i2c_ioctl_ops;
> +	data->vdev.release = video_i2c_release;
> +	data->vdev.device_caps = V4L2_CAP_VIDEO_CAPTURE |
> +				 V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
> +
> +	spin_lock_init(&data->slock);
> +	INIT_LIST_HEAD(&data->vid_cap_active);
> +
> +	video_set_drvdata(&data->vdev, data);
> +	i2c_set_clientdata(client, data);
> +
> +	ret = video_register_device(&data->vdev, VFL_TYPE_GRABBER, -1);
> +	if (ret < 0)
> +		goto error_unregister_device;
> +
> +	return 0;
> +
> +error_unregister_device:
> +	v4l2_device_unregister(v4l2_dev);
> +	mutex_destroy(&data->lock);
> +	mutex_destroy(&data->queue_lock);
> +
> +error_free_device:
> +	kfree(data);
> +
> +	return ret;
> +}
> +
> +static int video_i2c_remove(struct i2c_client *client)
> +{
> +	struct video_i2c_data *data = i2c_get_clientdata(client);
> +
> +	video_unregister_device(&data->vdev);
> +	v4l2_device_unregister(&data->v4l2_dev);
> +
> +	mutex_destroy(&data->lock);
> +	mutex_destroy(&data->queue_lock);
> +
> +	return 0;
> +}
> +
> +static const struct i2c_device_id video_i2c_id_table[] = {
> +	{ "amg88xx", AMG88XX },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, video_i2c_id_table);
> +
> +static const struct of_device_id video_i2c_of_match[] = {
> +	{ .compatible = "panasonic,amg88xx", .data = &video_i2c_chip[AMG88XX] },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, video_i2c_of_match);
> +
> +static struct i2c_driver video_i2c_driver = {
> +	.driver = {
> +		.name	= VIDEO_I2C_DRIVER,
> +		.of_match_table = video_i2c_of_match,
> +	},
> +	.probe		= video_i2c_probe,
> +	.remove		= video_i2c_remove,
> +	.id_table	= video_i2c_id_table,
> +};
> +
> +module_i2c_driver(video_i2c_driver);
> +
> +MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
> +MODULE_DESCRIPTION("I2C transport video support");
> +MODULE_LICENSE("GPL v2");

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi