diff mbox

[v3] media: video-i2c: add video-i2c driver

Message ID 20180224110555.16930-1-matt.ranostay@konsulko.com (mailing list archive)
State New, archived
Headers show

Commit Message

Matt Ranostay Feb. 24, 2018, 11:05 a.m. UTC
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.

Cc: Luca Barbato <lu_zero@gentoo.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
---
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

drivers/media/i2c/Kconfig     |   9 +
 drivers/media/i2c/Makefile    |   1 +
 drivers/media/i2c/video-i2c.c | 547 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 557 insertions(+)
 create mode 100644 drivers/media/i2c/video-i2c.c

Comments

Hans Verkuil Feb. 26, 2018, 11:52 a.m. UTC | #1
On 02/24/2018 12:05 PM, 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.
> 
> Cc: Luca Barbato <lu_zero@gentoo.org>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
> ---
> 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
> 
> drivers/media/i2c/Kconfig     |   9 +
>  drivers/media/i2c/Makefile    |   1 +
>  drivers/media/i2c/video-i2c.c | 547 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 557 insertions(+)
>  create mode 100644 drivers/media/i2c/video-i2c.c
> 
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 8fdd673d449f..53aede720e0f 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -917,6 +917,15 @@ 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
>  endmenu
>  
>  menu "Sensors used on soc_camera driver"
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index 26b19a2e9d04..5d4c06cb3f6f 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -91,6 +91,7 @@ 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..ea8ab2fcd580
> --- /dev/null
> +++ b/drivers/media/i2c/video-i2c.c
> @@ -0,0 +1,547 @@
> +// 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/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"
> +#define MAX_BUFFER_SIZE		128
> +
> +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;
> +	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;
> +}
> +
> +static const struct video_i2c_chip video_i2c_chip = {
> +	.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 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;
> +
> +	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_entry(data->vid_cap_active.next,
> +						 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();
> +			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 int start_streaming(struct vb2_queue *vq, unsigned int count)
> +{
> +	struct video_i2c_data *data = vb2_get_drv_priv(vq);
> +	struct video_i2c_buffer *buf, *tmp;
> +
> +	if (data->kthread_vid_cap)
> +		return 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;
> +
> +	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,
> +				VB2_BUF_STATE_QUEUED);
> +	}
> +
> +	spin_unlock(&data->slock);
> +
> +	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);
> +
> +	spin_lock(&data->slock);
> +
> +	while (!list_empty(&data->vid_cap_active)) {
> +		struct video_i2c_buffer *buf;
> +
> +		buf = list_entry(data->vid_cap_active.next,
> +				 struct video_i2c_buffer, list);
> +		list_del(&buf->list);
> +		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
> +	}
> +	spin_unlock(&data->slock);
> +
> +	data->kthread_vid_cap = NULL;
> +}
> +
> +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));
> +	sprintf(vcap->card, "I2C %d-%d Transport Video",
> +					     client->adapter->nr, client->addr);
> +
> +	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->width * pix->height * bpp;
> +	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;
> +
> +	data->chip = &video_i2c_chip;
> +	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_MMAP | VB2_USERPTR | VB2_READ;

Please add VB2_DMABUF. That's a valid and useful mode to have.

> +	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;
> +
> +	sprintf(data->vdev.name, "I2C %d-%d Transport Video",
> +				 client->adapter->nr, client->addr);

Please use snprintf.

> +
> +	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);
> +
> +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);
> +
> +	return 0;
> +}
> +
> +static const struct i2c_device_id video_i2c_id_table[] = {
> +	{ "amg88xx", 0 },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, video_i2c_id_table);

I strongly urge you to add the chip info pointer as the second argument
here (as mentioned in my previous review). It's very little work and it
makes it much easier to add new devices in the future.

> +
> +static const struct of_device_id video_i2c_of_match[] = {
> +	{ .compatible = "panasonic,amg88xx" },

Ah, no good deed goes unpunished :-)

Now that this has been added, you also need to add a bindings file.

See e.g. Documentation/devicetree/bindings/media/i2c/dongwoon,dw9714.txt
as a template. This should be done as a second patch and it should be Cc-ed
to devicetree@vger.kernel.org.

Luckily it's a trivial bindings file.

Also missing I see is an entry to the MAINTAINERS file for this driver.
Both the source and the bindings file should be mentioned in the entry.

> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, video_i2c_of_match);
> +
> +static struct i2c_driver video_i2c_driver = {
> +	.driver = {
> +		.name	= VIDEO_I2C_DRIVER,
> +		.of_match_table = of_match_ptr(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");
> 

Regards,

	Hans
diff mbox

Patch

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 8fdd673d449f..53aede720e0f 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -917,6 +917,15 @@  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
 endmenu
 
 menu "Sensors used on soc_camera driver"
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index 26b19a2e9d04..5d4c06cb3f6f 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -91,6 +91,7 @@  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..ea8ab2fcd580
--- /dev/null
+++ b/drivers/media/i2c/video-i2c.c
@@ -0,0 +1,547 @@ 
+// 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/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"
+#define MAX_BUFFER_SIZE		128
+
+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;
+	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;
+}
+
+static const struct video_i2c_chip video_i2c_chip = {
+	.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 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;
+
+	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_entry(data->vid_cap_active.next,
+						 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();
+			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 int start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct video_i2c_data *data = vb2_get_drv_priv(vq);
+	struct video_i2c_buffer *buf, *tmp;
+
+	if (data->kthread_vid_cap)
+		return 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;
+
+	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,
+				VB2_BUF_STATE_QUEUED);
+	}
+
+	spin_unlock(&data->slock);
+
+	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);
+
+	spin_lock(&data->slock);
+
+	while (!list_empty(&data->vid_cap_active)) {
+		struct video_i2c_buffer *buf;
+
+		buf = list_entry(data->vid_cap_active.next,
+				 struct video_i2c_buffer, list);
+		list_del(&buf->list);
+		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+	}
+	spin_unlock(&data->slock);
+
+	data->kthread_vid_cap = NULL;
+}
+
+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));
+	sprintf(vcap->card, "I2C %d-%d Transport Video",
+					     client->adapter->nr, client->addr);
+
+	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->width * pix->height * bpp;
+	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;
+
+	data->chip = &video_i2c_chip;
+	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_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;
+
+	sprintf(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);
+
+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);
+
+	return 0;
+}
+
+static const struct i2c_device_id video_i2c_id_table[] = {
+	{ "amg88xx", 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, video_i2c_id_table);
+
+static const struct of_device_id video_i2c_of_match[] = {
+	{ .compatible = "panasonic,amg88xx" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, video_i2c_of_match);
+
+static struct i2c_driver video_i2c_driver = {
+	.driver = {
+		.name	= VIDEO_I2C_DRIVER,
+		.of_match_table = of_match_ptr(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");