diff mbox series

[v4,1/3] v4l2-dev/ioctl: Add V4L2_CAP_IO_MC

Message ID 20200306163935.805333-2-niklas.soderlund@ragnatech.se (mailing list archive)
State Superseded
Headers show
Series v4l2-dev/ioctl: Add V4L2_CAP_IO_MC | expand

Commit Message

Niklas Söderlund March 6, 2020, 4:39 p.m. UTC
From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

Add a video device capability flag to indicate that its inputs and/or
outputs are controlled by the Media Controller instead of the V4L2 API.
When this flag is set, ioctl for enum inputs and outputs are
automatically enabled and programmed to call a helper function.

Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
---
* Changes since v3
- Update documentation for V4L2_CAP_IO_MC
- Only enable VIDIOC_{G,S}_{INPUT,OUTPUT} if V4L2_CAP_IO_MC is set
  (instead of unconditionally)
- Merge v4l2_ioctl_enum_input_mc() into v4l_enuminput()
- Merge v4l2_ioctl_enum_output_mc() into v4l_enumoutput()

* Changes since v2
- Merged the two patches touching V4L2 core stuff to a single patch.
- Updated documentation for V4L2_CAP_IO_MC
- Added is_io_mc bool in determine_valid_ioctls()
- Folded or moved code closer to where it's used
- Remove unneeded memset()
- Use strscpy() instead of strlcpy()
---
 .../media/uapi/v4l/vidioc-querycap.rst        |  6 ++
 .../media/videodev2.h.rst.exceptions          |  1 +
 drivers/media/v4l2-core/v4l2-dev.c            | 25 ++++++--
 drivers/media/v4l2-core/v4l2-ioctl.c          | 57 +++++++++++++++++--
 include/uapi/linux/videodev2.h                |  2 +
 5 files changed, 81 insertions(+), 10 deletions(-)

Comments

Sakari Ailus March 9, 2020, 1:47 p.m. UTC | #1
Hi Niklas,

Thanks for the update!

On Fri, Mar 06, 2020 at 05:39:33PM +0100, Niklas Söderlund wrote:
> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> 
> Add a video device capability flag to indicate that its inputs and/or
> outputs are controlled by the Media Controller instead of the V4L2 API.
> When this flag is set, ioctl for enum inputs and outputs are
> automatically enabled and programmed to call a helper function.
> 
> Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
> Signed-off-by: Helen Koike <helen.koike@collabora.com>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
> * Changes since v3
> - Update documentation for V4L2_CAP_IO_MC
> - Only enable VIDIOC_{G,S}_{INPUT,OUTPUT} if V4L2_CAP_IO_MC is set
>   (instead of unconditionally)
> - Merge v4l2_ioctl_enum_input_mc() into v4l_enuminput()
> - Merge v4l2_ioctl_enum_output_mc() into v4l_enumoutput()
> 
> * Changes since v2
> - Merged the two patches touching V4L2 core stuff to a single patch.
> - Updated documentation for V4L2_CAP_IO_MC
> - Added is_io_mc bool in determine_valid_ioctls()
> - Folded or moved code closer to where it's used
> - Remove unneeded memset()
> - Use strscpy() instead of strlcpy()
> ---
>  .../media/uapi/v4l/vidioc-querycap.rst        |  6 ++
>  .../media/videodev2.h.rst.exceptions          |  1 +
>  drivers/media/v4l2-core/v4l2-dev.c            | 25 ++++++--
>  drivers/media/v4l2-core/v4l2-ioctl.c          | 57 +++++++++++++++++--
>  include/uapi/linux/videodev2.h                |  2 +
>  5 files changed, 81 insertions(+), 10 deletions(-)
> 
> diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> index 5f9930195d624c73..497a6aa2cbebad71 100644
> --- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
> +++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> @@ -264,6 +264,12 @@ specification the ioctl returns an ``EINVAL`` error code.
>      * - ``V4L2_CAP_TOUCH``
>        - 0x10000000
>        - This is a touch device.
> +    * - ``V4L2_CAP_IO_MC``
> +      - 0x20000000
> +      - There is only one input and/or output seen from userspace. The whole
> +        video topology configuration, including which I/O entity is routed to
> +        the input/output, is configured by userspace via the Media Controller.
> +        See :ref:`media_controller`.
>      * - ``V4L2_CAP_DEVICE_CAPS``
>        - 0x80000000
>        - The driver fills the ``device_caps`` field. This capability can
> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
> index cb6ccf91776e6b56..a625fb90e3a989a7 100644
> --- a/Documentation/media/videodev2.h.rst.exceptions
> +++ b/Documentation/media/videodev2.h.rst.exceptions
> @@ -176,6 +176,7 @@ replace define V4L2_CAP_STREAMING device-capabilities
>  replace define V4L2_CAP_META_OUTPUT device-capabilities
>  replace define V4L2_CAP_DEVICE_CAPS device-capabilities
>  replace define V4L2_CAP_TOUCH device-capabilities
> +replace define V4L2_CAP_IO_MC device-capabilities
>  
>  # V4L2 pix flags
>  replace define V4L2_PIX_FMT_PRIV_MAGIC :c:type:`v4l2_pix_format`
> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> index 97b6a3af13614639..a593ea0598b551b4 100644
> --- a/drivers/media/v4l2-core/v4l2-dev.c
> +++ b/drivers/media/v4l2-core/v4l2-dev.c
> @@ -552,6 +552,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
>  		       (vdev->device_caps & meta_caps);
>  	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
>  	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
> +	bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
>  
>  	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
>  
> @@ -725,9 +726,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>  		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
>  		if (is_rx) {
>  			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> -			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> -			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> +			if (is_io_mc) {
> +				set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
> +			} else {
> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> +				SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> +				SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> +			}
>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
> @@ -735,9 +742,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>  			SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
>  		}
>  		if (is_tx) {
> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
> -			SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
> -			SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
> +			if (is_io_mc) {
> +				set_bit(_IOC_NR(VIDIOC_ENUMOUTPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_G_OUTPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_S_OUTPUT), valid_ioctls);
> +			} else {
> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
> +				SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
> +				SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
> +			}
>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index fbcc7a20eedf553a..58e9e728f0a7aa4b 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1085,6 +1085,32 @@ static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
>  	return ret;
>  }
>  
> +static int v4l_g_input(const struct v4l2_ioctl_ops *ops,
> +		       struct file *file, void *fh, void *arg)
> +{
> +	struct video_device *vfd = video_devdata(file);
> +
> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> +		*(unsigned int *)arg = 0;
> +		return 0;
> +	}
> +
> +	return ops->vidioc_g_input(file, fh, arg);
> +}
> +
> +static int v4l_g_output(const struct v4l2_ioctl_ops *ops,
> +		       struct file *file, void *fh, void *arg)
> +{
> +	struct video_device *vfd = video_devdata(file);
> +
> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> +		*(unsigned int *)arg = 0;
> +		return 0;
> +	}
> +
> +	return ops->vidioc_g_output(file, fh, arg);
> +}
> +
>  static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
>  				struct file *file, void *fh, void *arg)
>  {
> @@ -1094,12 +1120,21 @@ static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
>  	ret = v4l_enable_media_source(vfd);
>  	if (ret)
>  		return ret;
> +
> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
> +		return  *(unsigned int *)arg ? -EINVAL : 0;
> +
>  	return ops->vidioc_s_input(file, fh, *(unsigned int *)arg);
>  }
>  
>  static int v4l_s_output(const struct v4l2_ioctl_ops *ops,
>  				struct file *file, void *fh, void *arg)
>  {
> +	struct video_device *vfd = video_devdata(file);
> +
> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
> +		return  *(unsigned int *)arg ? -EINVAL : 0;

The type is int, not unsigned int. The same on the rest above.

> +
>  	return ops->vidioc_s_output(file, fh, *(unsigned int *)arg);
>  }
>  
> @@ -1143,6 +1178,14 @@ static int v4l_enuminput(const struct v4l2_ioctl_ops *ops,
>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
>  		p->capabilities |= V4L2_IN_CAP_STD;
>  
> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> +		if (p->index)
> +			return -EINVAL;
> +		strscpy(p->name, vfd->name, sizeof(p->name));
> +		p->type = V4L2_INPUT_TYPE_CAMERA;
> +		return 0;
> +	}
> +
>  	return ops->vidioc_enum_input(file, fh, p);
>  }
>  
> @@ -1161,6 +1204,14 @@ static int v4l_enumoutput(const struct v4l2_ioctl_ops *ops,
>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
>  		p->capabilities |= V4L2_OUT_CAP_STD;
>  
> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> +		if (p->index)
> +			return -EINVAL;
> +		strscpy(p->name, vfd->name, sizeof(p->name));
> +		p->type = V4L2_OUTPUT_TYPE_ANALOG;

How about adding a new INPUT and OUTPUT types just for IO_MC device cap?

This isn't necessarily a camera nor analogue output...

With these,

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

> +		return 0;
> +	}
> +
>  	return ops->vidioc_enum_output(file, fh, p);
>  }
>  
> @@ -2678,10 +2729,8 @@ DEFINE_V4L_STUB_FUNC(expbuf)
>  DEFINE_V4L_STUB_FUNC(g_std)
>  DEFINE_V4L_STUB_FUNC(g_audio)
>  DEFINE_V4L_STUB_FUNC(s_audio)
> -DEFINE_V4L_STUB_FUNC(g_input)
>  DEFINE_V4L_STUB_FUNC(g_edid)
>  DEFINE_V4L_STUB_FUNC(s_edid)
> -DEFINE_V4L_STUB_FUNC(g_output)
>  DEFINE_V4L_STUB_FUNC(g_audout)
>  DEFINE_V4L_STUB_FUNC(s_audout)
>  DEFINE_V4L_STUB_FUNC(g_jpegcomp)
> @@ -2730,11 +2779,11 @@ static const struct v4l2_ioctl_info v4l2_ioctls[] = {
>  	IOCTL_INFO(VIDIOC_S_AUDIO, v4l_stub_s_audio, v4l_print_audio, INFO_FL_PRIO),
>  	IOCTL_INFO(VIDIOC_QUERYCTRL, v4l_queryctrl, v4l_print_queryctrl, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_queryctrl, id)),
>  	IOCTL_INFO(VIDIOC_QUERYMENU, v4l_querymenu, v4l_print_querymenu, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_querymenu, index)),
> -	IOCTL_INFO(VIDIOC_G_INPUT, v4l_stub_g_input, v4l_print_u32, 0),
> +	IOCTL_INFO(VIDIOC_G_INPUT, v4l_g_input, v4l_print_u32, 0),
>  	IOCTL_INFO(VIDIOC_S_INPUT, v4l_s_input, v4l_print_u32, INFO_FL_PRIO),
>  	IOCTL_INFO(VIDIOC_G_EDID, v4l_stub_g_edid, v4l_print_edid, INFO_FL_ALWAYS_COPY),
>  	IOCTL_INFO(VIDIOC_S_EDID, v4l_stub_s_edid, v4l_print_edid, INFO_FL_PRIO | INFO_FL_ALWAYS_COPY),
> -	IOCTL_INFO(VIDIOC_G_OUTPUT, v4l_stub_g_output, v4l_print_u32, 0),
> +	IOCTL_INFO(VIDIOC_G_OUTPUT, v4l_g_output, v4l_print_u32, 0),
>  	IOCTL_INFO(VIDIOC_S_OUTPUT, v4l_s_output, v4l_print_u32, INFO_FL_PRIO),
>  	IOCTL_INFO(VIDIOC_ENUMOUTPUT, v4l_enumoutput, v4l_print_enumoutput, INFO_FL_CLEAR(v4l2_output, index)),
>  	IOCTL_INFO(VIDIOC_G_AUDOUT, v4l_stub_g_audout, v4l_print_audioout, 0),
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 5f9357dcb0602126..c793263a37052856 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -487,6 +487,8 @@ struct v4l2_capability {
>  
>  #define V4L2_CAP_TOUCH                  0x10000000  /* Is a touch device */
>  
> +#define V4L2_CAP_IO_MC			0x20000000  /* Is input/output controlled by the media controller */
> +
>  #define V4L2_CAP_DEVICE_CAPS            0x80000000  /* sets device capabilities field */
>  
>  /*
Sakari Ailus March 9, 2020, 1:52 p.m. UTC | #2
Hi Niklas,

On Fri, Mar 06, 2020 at 05:39:33PM +0100, Niklas Söderlund wrote:
> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> 
> Add a video device capability flag to indicate that its inputs and/or
> outputs are controlled by the Media Controller instead of the V4L2 API.
> When this flag is set, ioctl for enum inputs and outputs are
> automatically enabled and programmed to call a helper function.
> 
> Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
> Signed-off-by: Helen Koike <helen.koike@collabora.com>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
> * Changes since v3
> - Update documentation for V4L2_CAP_IO_MC
> - Only enable VIDIOC_{G,S}_{INPUT,OUTPUT} if V4L2_CAP_IO_MC is set
>   (instead of unconditionally)
> - Merge v4l2_ioctl_enum_input_mc() into v4l_enuminput()
> - Merge v4l2_ioctl_enum_output_mc() into v4l_enumoutput()
> 
> * Changes since v2
> - Merged the two patches touching V4L2 core stuff to a single patch.
> - Updated documentation for V4L2_CAP_IO_MC
> - Added is_io_mc bool in determine_valid_ioctls()
> - Folded or moved code closer to where it's used
> - Remove unneeded memset()
> - Use strscpy() instead of strlcpy()
> ---
>  .../media/uapi/v4l/vidioc-querycap.rst        |  6 ++
>  .../media/videodev2.h.rst.exceptions          |  1 +
>  drivers/media/v4l2-core/v4l2-dev.c            | 25 ++++++--
>  drivers/media/v4l2-core/v4l2-ioctl.c          | 57 +++++++++++++++++--
>  include/uapi/linux/videodev2.h                |  2 +
>  5 files changed, 81 insertions(+), 10 deletions(-)
> 
> diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> index 5f9930195d624c73..497a6aa2cbebad71 100644
> --- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
> +++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> @@ -264,6 +264,12 @@ specification the ioctl returns an ``EINVAL`` error code.
>      * - ``V4L2_CAP_TOUCH``
>        - 0x10000000
>        - This is a touch device.
> +    * - ``V4L2_CAP_IO_MC``
> +      - 0x20000000
> +      - There is only one input and/or output seen from userspace. The whole
> +        video topology configuration, including which I/O entity is routed to
> +        the input/output, is configured by userspace via the Media Controller.
> +        See :ref:`media_controller`.
>      * - ``V4L2_CAP_DEVICE_CAPS``
>        - 0x80000000
>        - The driver fills the ``device_caps`` field. This capability can
> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
> index cb6ccf91776e6b56..a625fb90e3a989a7 100644
> --- a/Documentation/media/videodev2.h.rst.exceptions
> +++ b/Documentation/media/videodev2.h.rst.exceptions
> @@ -176,6 +176,7 @@ replace define V4L2_CAP_STREAMING device-capabilities
>  replace define V4L2_CAP_META_OUTPUT device-capabilities
>  replace define V4L2_CAP_DEVICE_CAPS device-capabilities
>  replace define V4L2_CAP_TOUCH device-capabilities
> +replace define V4L2_CAP_IO_MC device-capabilities
>  
>  # V4L2 pix flags
>  replace define V4L2_PIX_FMT_PRIV_MAGIC :c:type:`v4l2_pix_format`
> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> index 97b6a3af13614639..a593ea0598b551b4 100644
> --- a/drivers/media/v4l2-core/v4l2-dev.c
> +++ b/drivers/media/v4l2-core/v4l2-dev.c
> @@ -552,6 +552,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
>  		       (vdev->device_caps & meta_caps);
>  	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
>  	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
> +	bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
>  
>  	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
>  
> @@ -725,9 +726,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>  		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
>  		if (is_rx) {
>  			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> -			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> -			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> +			if (is_io_mc) {

One more comment.

I'd make this dependent on the device node type, i.e. devices with
meta_caps set, the IOCTLs won't be supported.

So the check would become:

			if (is_io_mc && !is_meta)

> +				set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
> +			} else {
> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> +				SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> +				SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> +			}
>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
Hans Verkuil March 9, 2020, 1:53 p.m. UTC | #3
On 3/9/20 2:47 PM, Sakari Ailus wrote:
> Hi Niklas,
> 
> Thanks for the update!
> 
> On Fri, Mar 06, 2020 at 05:39:33PM +0100, Niklas Söderlund wrote:
>> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
>>
>> Add a video device capability flag to indicate that its inputs and/or
>> outputs are controlled by the Media Controller instead of the V4L2 API.
>> When this flag is set, ioctl for enum inputs and outputs are
>> automatically enabled and programmed to call a helper function.
>>
>> Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
>> Signed-off-by: Helen Koike <helen.koike@collabora.com>
>> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
>> ---
>> * Changes since v3
>> - Update documentation for V4L2_CAP_IO_MC
>> - Only enable VIDIOC_{G,S}_{INPUT,OUTPUT} if V4L2_CAP_IO_MC is set
>>   (instead of unconditionally)
>> - Merge v4l2_ioctl_enum_input_mc() into v4l_enuminput()
>> - Merge v4l2_ioctl_enum_output_mc() into v4l_enumoutput()
>>
>> * Changes since v2
>> - Merged the two patches touching V4L2 core stuff to a single patch.
>> - Updated documentation for V4L2_CAP_IO_MC
>> - Added is_io_mc bool in determine_valid_ioctls()
>> - Folded or moved code closer to where it's used
>> - Remove unneeded memset()
>> - Use strscpy() instead of strlcpy()
>> ---
>>  .../media/uapi/v4l/vidioc-querycap.rst        |  6 ++
>>  .../media/videodev2.h.rst.exceptions          |  1 +
>>  drivers/media/v4l2-core/v4l2-dev.c            | 25 ++++++--
>>  drivers/media/v4l2-core/v4l2-ioctl.c          | 57 +++++++++++++++++--
>>  include/uapi/linux/videodev2.h                |  2 +
>>  5 files changed, 81 insertions(+), 10 deletions(-)
>>
>> diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
>> index 5f9930195d624c73..497a6aa2cbebad71 100644
>> --- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
>> +++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
>> @@ -264,6 +264,12 @@ specification the ioctl returns an ``EINVAL`` error code.
>>      * - ``V4L2_CAP_TOUCH``
>>        - 0x10000000
>>        - This is a touch device.
>> +    * - ``V4L2_CAP_IO_MC``
>> +      - 0x20000000
>> +      - There is only one input and/or output seen from userspace. The whole
>> +        video topology configuration, including which I/O entity is routed to
>> +        the input/output, is configured by userspace via the Media Controller.
>> +        See :ref:`media_controller`.
>>      * - ``V4L2_CAP_DEVICE_CAPS``
>>        - 0x80000000
>>        - The driver fills the ``device_caps`` field. This capability can
>> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
>> index cb6ccf91776e6b56..a625fb90e3a989a7 100644
>> --- a/Documentation/media/videodev2.h.rst.exceptions
>> +++ b/Documentation/media/videodev2.h.rst.exceptions
>> @@ -176,6 +176,7 @@ replace define V4L2_CAP_STREAMING device-capabilities
>>  replace define V4L2_CAP_META_OUTPUT device-capabilities
>>  replace define V4L2_CAP_DEVICE_CAPS device-capabilities
>>  replace define V4L2_CAP_TOUCH device-capabilities
>> +replace define V4L2_CAP_IO_MC device-capabilities
>>  
>>  # V4L2 pix flags
>>  replace define V4L2_PIX_FMT_PRIV_MAGIC :c:type:`v4l2_pix_format`
>> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
>> index 97b6a3af13614639..a593ea0598b551b4 100644
>> --- a/drivers/media/v4l2-core/v4l2-dev.c
>> +++ b/drivers/media/v4l2-core/v4l2-dev.c
>> @@ -552,6 +552,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
>>  		       (vdev->device_caps & meta_caps);
>>  	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
>>  	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
>> +	bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
>>  
>>  	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
>>  
>> @@ -725,9 +726,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>>  		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
>>  		if (is_rx) {
>>  			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
>> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
>> -			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
>> -			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
>> +			if (is_io_mc) {
>> +				set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
>> +				set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
>> +				set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
>> +			} else {
>> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
>> +				SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
>> +				SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
>> +			}
>>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
>>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
>>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
>> @@ -735,9 +742,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>>  			SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
>>  		}
>>  		if (is_tx) {
>> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
>> -			SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
>> -			SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
>> +			if (is_io_mc) {
>> +				set_bit(_IOC_NR(VIDIOC_ENUMOUTPUT), valid_ioctls);
>> +				set_bit(_IOC_NR(VIDIOC_G_OUTPUT), valid_ioctls);
>> +				set_bit(_IOC_NR(VIDIOC_S_OUTPUT), valid_ioctls);
>> +			} else {
>> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
>> +				SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
>> +				SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
>> +			}
>>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
>>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
>>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
>> index fbcc7a20eedf553a..58e9e728f0a7aa4b 100644
>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
>> @@ -1085,6 +1085,32 @@ static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
>>  	return ret;
>>  }
>>  
>> +static int v4l_g_input(const struct v4l2_ioctl_ops *ops,
>> +		       struct file *file, void *fh, void *arg)
>> +{
>> +	struct video_device *vfd = video_devdata(file);
>> +
>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
>> +		*(unsigned int *)arg = 0;
>> +		return 0;
>> +	}
>> +
>> +	return ops->vidioc_g_input(file, fh, arg);
>> +}
>> +
>> +static int v4l_g_output(const struct v4l2_ioctl_ops *ops,
>> +		       struct file *file, void *fh, void *arg)
>> +{
>> +	struct video_device *vfd = video_devdata(file);
>> +
>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
>> +		*(unsigned int *)arg = 0;
>> +		return 0;
>> +	}
>> +
>> +	return ops->vidioc_g_output(file, fh, arg);
>> +}
>> +
>>  static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
>>  				struct file *file, void *fh, void *arg)
>>  {
>> @@ -1094,12 +1120,21 @@ static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
>>  	ret = v4l_enable_media_source(vfd);
>>  	if (ret)
>>  		return ret;
>> +
>> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
>> +		return  *(unsigned int *)arg ? -EINVAL : 0;
>> +
>>  	return ops->vidioc_s_input(file, fh, *(unsigned int *)arg);
>>  }
>>  
>>  static int v4l_s_output(const struct v4l2_ioctl_ops *ops,
>>  				struct file *file, void *fh, void *arg)
>>  {
>> +	struct video_device *vfd = video_devdata(file);
>> +
>> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
>> +		return  *(unsigned int *)arg ? -EINVAL : 0;
> 
> The type is int, not unsigned int. The same on the rest above.
> 
>> +
>>  	return ops->vidioc_s_output(file, fh, *(unsigned int *)arg);
>>  }
>>  
>> @@ -1143,6 +1178,14 @@ static int v4l_enuminput(const struct v4l2_ioctl_ops *ops,
>>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
>>  		p->capabilities |= V4L2_IN_CAP_STD;
>>  
>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
>> +		if (p->index)
>> +			return -EINVAL;
>> +		strscpy(p->name, vfd->name, sizeof(p->name));
>> +		p->type = V4L2_INPUT_TYPE_CAMERA;
>> +		return 0;
>> +	}
>> +
>>  	return ops->vidioc_enum_input(file, fh, p);
>>  }
>>  
>> @@ -1161,6 +1204,14 @@ static int v4l_enumoutput(const struct v4l2_ioctl_ops *ops,
>>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
>>  		p->capabilities |= V4L2_OUT_CAP_STD;
>>  
>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
>> +		if (p->index)
>> +			return -EINVAL;
>> +		strscpy(p->name, vfd->name, sizeof(p->name));
>> +		p->type = V4L2_OUTPUT_TYPE_ANALOG;
> 
> How about adding a new INPUT and OUTPUT types just for IO_MC device cap?

V4L2_OUTPUT_TYPE_ANALOG is an old term that is in practice used for anything video,
except for TV modulators. I'm all in favor of changing this to:

#define V4L2_OUTPUT_TYPE_VIDEO 2
#ifndef __KERNEL__
#define V4L2_OUTPUT_TYPE_ANALOG V4L2_OUTPUT_TYPE_VIDEO
#endif

in videodev2.h, if others agree with that. But that can be done in a separate
follow-up patch since this needs to be adapted throughout the kernel & documentation.

The same is true for V4L2_INPUT_TYPE_CAMERA: in practice it's used for any video,
except TV tuners.

Regards,

	Hans

> 
> This isn't necessarily a camera nor analogue output...
> 
> With these,
> 
> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> 
>> +		return 0;
>> +	}
>> +
>>  	return ops->vidioc_enum_output(file, fh, p);
>>  }
>>  
>> @@ -2678,10 +2729,8 @@ DEFINE_V4L_STUB_FUNC(expbuf)
>>  DEFINE_V4L_STUB_FUNC(g_std)
>>  DEFINE_V4L_STUB_FUNC(g_audio)
>>  DEFINE_V4L_STUB_FUNC(s_audio)
>> -DEFINE_V4L_STUB_FUNC(g_input)
>>  DEFINE_V4L_STUB_FUNC(g_edid)
>>  DEFINE_V4L_STUB_FUNC(s_edid)
>> -DEFINE_V4L_STUB_FUNC(g_output)
>>  DEFINE_V4L_STUB_FUNC(g_audout)
>>  DEFINE_V4L_STUB_FUNC(s_audout)
>>  DEFINE_V4L_STUB_FUNC(g_jpegcomp)
>> @@ -2730,11 +2779,11 @@ static const struct v4l2_ioctl_info v4l2_ioctls[] = {
>>  	IOCTL_INFO(VIDIOC_S_AUDIO, v4l_stub_s_audio, v4l_print_audio, INFO_FL_PRIO),
>>  	IOCTL_INFO(VIDIOC_QUERYCTRL, v4l_queryctrl, v4l_print_queryctrl, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_queryctrl, id)),
>>  	IOCTL_INFO(VIDIOC_QUERYMENU, v4l_querymenu, v4l_print_querymenu, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_querymenu, index)),
>> -	IOCTL_INFO(VIDIOC_G_INPUT, v4l_stub_g_input, v4l_print_u32, 0),
>> +	IOCTL_INFO(VIDIOC_G_INPUT, v4l_g_input, v4l_print_u32, 0),
>>  	IOCTL_INFO(VIDIOC_S_INPUT, v4l_s_input, v4l_print_u32, INFO_FL_PRIO),
>>  	IOCTL_INFO(VIDIOC_G_EDID, v4l_stub_g_edid, v4l_print_edid, INFO_FL_ALWAYS_COPY),
>>  	IOCTL_INFO(VIDIOC_S_EDID, v4l_stub_s_edid, v4l_print_edid, INFO_FL_PRIO | INFO_FL_ALWAYS_COPY),
>> -	IOCTL_INFO(VIDIOC_G_OUTPUT, v4l_stub_g_output, v4l_print_u32, 0),
>> +	IOCTL_INFO(VIDIOC_G_OUTPUT, v4l_g_output, v4l_print_u32, 0),
>>  	IOCTL_INFO(VIDIOC_S_OUTPUT, v4l_s_output, v4l_print_u32, INFO_FL_PRIO),
>>  	IOCTL_INFO(VIDIOC_ENUMOUTPUT, v4l_enumoutput, v4l_print_enumoutput, INFO_FL_CLEAR(v4l2_output, index)),
>>  	IOCTL_INFO(VIDIOC_G_AUDOUT, v4l_stub_g_audout, v4l_print_audioout, 0),
>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>> index 5f9357dcb0602126..c793263a37052856 100644
>> --- a/include/uapi/linux/videodev2.h
>> +++ b/include/uapi/linux/videodev2.h
>> @@ -487,6 +487,8 @@ struct v4l2_capability {
>>  
>>  #define V4L2_CAP_TOUCH                  0x10000000  /* Is a touch device */
>>  
>> +#define V4L2_CAP_IO_MC			0x20000000  /* Is input/output controlled by the media controller */
>> +
>>  #define V4L2_CAP_DEVICE_CAPS            0x80000000  /* sets device capabilities field */
>>  
>>  /*
>
Sakari Ailus March 9, 2020, 1:56 p.m. UTC | #4
Hi Hans,

On Mon, Mar 09, 2020 at 02:53:15PM +0100, Hans Verkuil wrote:
> On 3/9/20 2:47 PM, Sakari Ailus wrote:
> > Hi Niklas,
> > 
> > Thanks for the update!
> > 
> > On Fri, Mar 06, 2020 at 05:39:33PM +0100, Niklas Söderlund wrote:
> >> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> >>
> >> Add a video device capability flag to indicate that its inputs and/or
> >> outputs are controlled by the Media Controller instead of the V4L2 API.
> >> When this flag is set, ioctl for enum inputs and outputs are
> >> automatically enabled and programmed to call a helper function.
> >>
> >> Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
> >> Signed-off-by: Helen Koike <helen.koike@collabora.com>
> >> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> >> ---
> >> * Changes since v3
> >> - Update documentation for V4L2_CAP_IO_MC
> >> - Only enable VIDIOC_{G,S}_{INPUT,OUTPUT} if V4L2_CAP_IO_MC is set
> >>   (instead of unconditionally)
> >> - Merge v4l2_ioctl_enum_input_mc() into v4l_enuminput()
> >> - Merge v4l2_ioctl_enum_output_mc() into v4l_enumoutput()
> >>
> >> * Changes since v2
> >> - Merged the two patches touching V4L2 core stuff to a single patch.
> >> - Updated documentation for V4L2_CAP_IO_MC
> >> - Added is_io_mc bool in determine_valid_ioctls()
> >> - Folded or moved code closer to where it's used
> >> - Remove unneeded memset()
> >> - Use strscpy() instead of strlcpy()
> >> ---
> >>  .../media/uapi/v4l/vidioc-querycap.rst        |  6 ++
> >>  .../media/videodev2.h.rst.exceptions          |  1 +
> >>  drivers/media/v4l2-core/v4l2-dev.c            | 25 ++++++--
> >>  drivers/media/v4l2-core/v4l2-ioctl.c          | 57 +++++++++++++++++--
> >>  include/uapi/linux/videodev2.h                |  2 +
> >>  5 files changed, 81 insertions(+), 10 deletions(-)
> >>
> >> diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> >> index 5f9930195d624c73..497a6aa2cbebad71 100644
> >> --- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
> >> +++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> >> @@ -264,6 +264,12 @@ specification the ioctl returns an ``EINVAL`` error code.
> >>      * - ``V4L2_CAP_TOUCH``
> >>        - 0x10000000
> >>        - This is a touch device.
> >> +    * - ``V4L2_CAP_IO_MC``
> >> +      - 0x20000000
> >> +      - There is only one input and/or output seen from userspace. The whole
> >> +        video topology configuration, including which I/O entity is routed to
> >> +        the input/output, is configured by userspace via the Media Controller.
> >> +        See :ref:`media_controller`.
> >>      * - ``V4L2_CAP_DEVICE_CAPS``
> >>        - 0x80000000
> >>        - The driver fills the ``device_caps`` field. This capability can
> >> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
> >> index cb6ccf91776e6b56..a625fb90e3a989a7 100644
> >> --- a/Documentation/media/videodev2.h.rst.exceptions
> >> +++ b/Documentation/media/videodev2.h.rst.exceptions
> >> @@ -176,6 +176,7 @@ replace define V4L2_CAP_STREAMING device-capabilities
> >>  replace define V4L2_CAP_META_OUTPUT device-capabilities
> >>  replace define V4L2_CAP_DEVICE_CAPS device-capabilities
> >>  replace define V4L2_CAP_TOUCH device-capabilities
> >> +replace define V4L2_CAP_IO_MC device-capabilities
> >>  
> >>  # V4L2 pix flags
> >>  replace define V4L2_PIX_FMT_PRIV_MAGIC :c:type:`v4l2_pix_format`
> >> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> >> index 97b6a3af13614639..a593ea0598b551b4 100644
> >> --- a/drivers/media/v4l2-core/v4l2-dev.c
> >> +++ b/drivers/media/v4l2-core/v4l2-dev.c
> >> @@ -552,6 +552,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
> >>  		       (vdev->device_caps & meta_caps);
> >>  	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
> >>  	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
> >> +	bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
> >>  
> >>  	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
> >>  
> >> @@ -725,9 +726,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
> >>  		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
> >>  		if (is_rx) {
> >>  			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
> >> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> >> -			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> >> -			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> >> +			if (is_io_mc) {
> >> +				set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
> >> +				set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
> >> +				set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
> >> +			} else {
> >> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> >> +				SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> >> +				SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> >> +			}
> >>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
> >>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
> >>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
> >> @@ -735,9 +742,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
> >>  			SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
> >>  		}
> >>  		if (is_tx) {
> >> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
> >> -			SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
> >> -			SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
> >> +			if (is_io_mc) {
> >> +				set_bit(_IOC_NR(VIDIOC_ENUMOUTPUT), valid_ioctls);
> >> +				set_bit(_IOC_NR(VIDIOC_G_OUTPUT), valid_ioctls);
> >> +				set_bit(_IOC_NR(VIDIOC_S_OUTPUT), valid_ioctls);
> >> +			} else {
> >> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
> >> +				SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
> >> +				SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
> >> +			}
> >>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
> >>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
> >>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
> >> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> >> index fbcc7a20eedf553a..58e9e728f0a7aa4b 100644
> >> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> >> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> >> @@ -1085,6 +1085,32 @@ static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
> >>  	return ret;
> >>  }
> >>  
> >> +static int v4l_g_input(const struct v4l2_ioctl_ops *ops,
> >> +		       struct file *file, void *fh, void *arg)
> >> +{
> >> +	struct video_device *vfd = video_devdata(file);
> >> +
> >> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> >> +		*(unsigned int *)arg = 0;
> >> +		return 0;
> >> +	}
> >> +
> >> +	return ops->vidioc_g_input(file, fh, arg);
> >> +}
> >> +
> >> +static int v4l_g_output(const struct v4l2_ioctl_ops *ops,
> >> +		       struct file *file, void *fh, void *arg)
> >> +{
> >> +	struct video_device *vfd = video_devdata(file);
> >> +
> >> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> >> +		*(unsigned int *)arg = 0;
> >> +		return 0;
> >> +	}
> >> +
> >> +	return ops->vidioc_g_output(file, fh, arg);
> >> +}
> >> +
> >>  static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
> >>  				struct file *file, void *fh, void *arg)
> >>  {
> >> @@ -1094,12 +1120,21 @@ static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
> >>  	ret = v4l_enable_media_source(vfd);
> >>  	if (ret)
> >>  		return ret;
> >> +
> >> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
> >> +		return  *(unsigned int *)arg ? -EINVAL : 0;
> >> +
> >>  	return ops->vidioc_s_input(file, fh, *(unsigned int *)arg);
> >>  }
> >>  
> >>  static int v4l_s_output(const struct v4l2_ioctl_ops *ops,
> >>  				struct file *file, void *fh, void *arg)
> >>  {
> >> +	struct video_device *vfd = video_devdata(file);
> >> +
> >> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
> >> +		return  *(unsigned int *)arg ? -EINVAL : 0;
> > 
> > The type is int, not unsigned int. The same on the rest above.
> > 
> >> +
> >>  	return ops->vidioc_s_output(file, fh, *(unsigned int *)arg);
> >>  }
> >>  
> >> @@ -1143,6 +1178,14 @@ static int v4l_enuminput(const struct v4l2_ioctl_ops *ops,
> >>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
> >>  		p->capabilities |= V4L2_IN_CAP_STD;
> >>  
> >> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> >> +		if (p->index)
> >> +			return -EINVAL;
> >> +		strscpy(p->name, vfd->name, sizeof(p->name));
> >> +		p->type = V4L2_INPUT_TYPE_CAMERA;
> >> +		return 0;
> >> +	}
> >> +
> >>  	return ops->vidioc_enum_input(file, fh, p);
> >>  }
> >>  
> >> @@ -1161,6 +1204,14 @@ static int v4l_enumoutput(const struct v4l2_ioctl_ops *ops,
> >>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
> >>  		p->capabilities |= V4L2_OUT_CAP_STD;
> >>  
> >> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> >> +		if (p->index)
> >> +			return -EINVAL;
> >> +		strscpy(p->name, vfd->name, sizeof(p->name));
> >> +		p->type = V4L2_OUTPUT_TYPE_ANALOG;
> > 
> > How about adding a new INPUT and OUTPUT types just for IO_MC device cap?
> 
> V4L2_OUTPUT_TYPE_ANALOG is an old term that is in practice used for anything video,
> except for TV modulators. I'm all in favor of changing this to:
> 
> #define V4L2_OUTPUT_TYPE_VIDEO 2
> #ifndef __KERNEL__
> #define V4L2_OUTPUT_TYPE_ANALOG V4L2_OUTPUT_TYPE_VIDEO
> #endif
> 
> in videodev2.h, if others agree with that. But that can be done in a separate
> follow-up patch since this needs to be adapted throughout the kernel & documentation.
> 
> The same is true for V4L2_INPUT_TYPE_CAMERA: in practice it's used for any video,
> except TV tuners.

My point was rather that here, we don't know what kind of device really is
the source (or the sink) of the data path. Having a designated input and
output type for that would be entirely appropriate.

Although if the user gets a misleading value using an interface that
(s)he's not supposed to use to begin with, I guess I'd fine with that as
well.
Hans Verkuil March 9, 2020, 2:10 p.m. UTC | #5
On 3/9/20 2:56 PM, Sakari Ailus wrote:
> Hi Hans,
> 
> On Mon, Mar 09, 2020 at 02:53:15PM +0100, Hans Verkuil wrote:
>> On 3/9/20 2:47 PM, Sakari Ailus wrote:
>>> Hi Niklas,
>>>
>>> Thanks for the update!
>>>
>>> On Fri, Mar 06, 2020 at 05:39:33PM +0100, Niklas Söderlund wrote:
>>>> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
>>>>
>>>> Add a video device capability flag to indicate that its inputs and/or
>>>> outputs are controlled by the Media Controller instead of the V4L2 API.
>>>> When this flag is set, ioctl for enum inputs and outputs are
>>>> automatically enabled and programmed to call a helper function.
>>>>
>>>> Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
>>>> Signed-off-by: Helen Koike <helen.koike@collabora.com>
>>>> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
>>>> ---
>>>> * Changes since v3
>>>> - Update documentation for V4L2_CAP_IO_MC
>>>> - Only enable VIDIOC_{G,S}_{INPUT,OUTPUT} if V4L2_CAP_IO_MC is set
>>>>   (instead of unconditionally)
>>>> - Merge v4l2_ioctl_enum_input_mc() into v4l_enuminput()
>>>> - Merge v4l2_ioctl_enum_output_mc() into v4l_enumoutput()
>>>>
>>>> * Changes since v2
>>>> - Merged the two patches touching V4L2 core stuff to a single patch.
>>>> - Updated documentation for V4L2_CAP_IO_MC
>>>> - Added is_io_mc bool in determine_valid_ioctls()
>>>> - Folded or moved code closer to where it's used
>>>> - Remove unneeded memset()
>>>> - Use strscpy() instead of strlcpy()
>>>> ---
>>>>  .../media/uapi/v4l/vidioc-querycap.rst        |  6 ++
>>>>  .../media/videodev2.h.rst.exceptions          |  1 +
>>>>  drivers/media/v4l2-core/v4l2-dev.c            | 25 ++++++--
>>>>  drivers/media/v4l2-core/v4l2-ioctl.c          | 57 +++++++++++++++++--
>>>>  include/uapi/linux/videodev2.h                |  2 +
>>>>  5 files changed, 81 insertions(+), 10 deletions(-)
>>>>
>>>> diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
>>>> index 5f9930195d624c73..497a6aa2cbebad71 100644
>>>> --- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
>>>> +++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
>>>> @@ -264,6 +264,12 @@ specification the ioctl returns an ``EINVAL`` error code.
>>>>      * - ``V4L2_CAP_TOUCH``
>>>>        - 0x10000000
>>>>        - This is a touch device.
>>>> +    * - ``V4L2_CAP_IO_MC``
>>>> +      - 0x20000000
>>>> +      - There is only one input and/or output seen from userspace. The whole
>>>> +        video topology configuration, including which I/O entity is routed to
>>>> +        the input/output, is configured by userspace via the Media Controller.
>>>> +        See :ref:`media_controller`.
>>>>      * - ``V4L2_CAP_DEVICE_CAPS``
>>>>        - 0x80000000
>>>>        - The driver fills the ``device_caps`` field. This capability can
>>>> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
>>>> index cb6ccf91776e6b56..a625fb90e3a989a7 100644
>>>> --- a/Documentation/media/videodev2.h.rst.exceptions
>>>> +++ b/Documentation/media/videodev2.h.rst.exceptions
>>>> @@ -176,6 +176,7 @@ replace define V4L2_CAP_STREAMING device-capabilities
>>>>  replace define V4L2_CAP_META_OUTPUT device-capabilities
>>>>  replace define V4L2_CAP_DEVICE_CAPS device-capabilities
>>>>  replace define V4L2_CAP_TOUCH device-capabilities
>>>> +replace define V4L2_CAP_IO_MC device-capabilities
>>>>  
>>>>  # V4L2 pix flags
>>>>  replace define V4L2_PIX_FMT_PRIV_MAGIC :c:type:`v4l2_pix_format`
>>>> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
>>>> index 97b6a3af13614639..a593ea0598b551b4 100644
>>>> --- a/drivers/media/v4l2-core/v4l2-dev.c
>>>> +++ b/drivers/media/v4l2-core/v4l2-dev.c
>>>> @@ -552,6 +552,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
>>>>  		       (vdev->device_caps & meta_caps);
>>>>  	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
>>>>  	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
>>>> +	bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
>>>>  
>>>>  	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
>>>>  
>>>> @@ -725,9 +726,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>>>>  		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
>>>>  		if (is_rx) {
>>>>  			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
>>>> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
>>>> -			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
>>>> -			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
>>>> +			if (is_io_mc) {
>>>> +				set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
>>>> +				set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
>>>> +				set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
>>>> +			} else {
>>>> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
>>>> +				SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
>>>> +				SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
>>>> +			}
>>>>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
>>>>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
>>>>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
>>>> @@ -735,9 +742,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>>>>  			SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
>>>>  		}
>>>>  		if (is_tx) {
>>>> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
>>>> -			SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
>>>> -			SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
>>>> +			if (is_io_mc) {
>>>> +				set_bit(_IOC_NR(VIDIOC_ENUMOUTPUT), valid_ioctls);
>>>> +				set_bit(_IOC_NR(VIDIOC_G_OUTPUT), valid_ioctls);
>>>> +				set_bit(_IOC_NR(VIDIOC_S_OUTPUT), valid_ioctls);
>>>> +			} else {
>>>> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
>>>> +				SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
>>>> +				SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
>>>> +			}
>>>>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
>>>>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
>>>>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
>>>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> index fbcc7a20eedf553a..58e9e728f0a7aa4b 100644
>>>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
>>>> @@ -1085,6 +1085,32 @@ static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
>>>>  	return ret;
>>>>  }
>>>>  
>>>> +static int v4l_g_input(const struct v4l2_ioctl_ops *ops,
>>>> +		       struct file *file, void *fh, void *arg)
>>>> +{
>>>> +	struct video_device *vfd = video_devdata(file);
>>>> +
>>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
>>>> +		*(unsigned int *)arg = 0;
>>>> +		return 0;
>>>> +	}
>>>> +
>>>> +	return ops->vidioc_g_input(file, fh, arg);
>>>> +}
>>>> +
>>>> +static int v4l_g_output(const struct v4l2_ioctl_ops *ops,
>>>> +		       struct file *file, void *fh, void *arg)
>>>> +{
>>>> +	struct video_device *vfd = video_devdata(file);
>>>> +
>>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
>>>> +		*(unsigned int *)arg = 0;
>>>> +		return 0;
>>>> +	}
>>>> +
>>>> +	return ops->vidioc_g_output(file, fh, arg);
>>>> +}
>>>> +
>>>>  static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
>>>>  				struct file *file, void *fh, void *arg)
>>>>  {
>>>> @@ -1094,12 +1120,21 @@ static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
>>>>  	ret = v4l_enable_media_source(vfd);
>>>>  	if (ret)
>>>>  		return ret;
>>>> +
>>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
>>>> +		return  *(unsigned int *)arg ? -EINVAL : 0;
>>>> +
>>>>  	return ops->vidioc_s_input(file, fh, *(unsigned int *)arg);
>>>>  }
>>>>  
>>>>  static int v4l_s_output(const struct v4l2_ioctl_ops *ops,
>>>>  				struct file *file, void *fh, void *arg)
>>>>  {
>>>> +	struct video_device *vfd = video_devdata(file);
>>>> +
>>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
>>>> +		return  *(unsigned int *)arg ? -EINVAL : 0;
>>>
>>> The type is int, not unsigned int. The same on the rest above.
>>>
>>>> +
>>>>  	return ops->vidioc_s_output(file, fh, *(unsigned int *)arg);
>>>>  }
>>>>  
>>>> @@ -1143,6 +1178,14 @@ static int v4l_enuminput(const struct v4l2_ioctl_ops *ops,
>>>>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
>>>>  		p->capabilities |= V4L2_IN_CAP_STD;
>>>>  
>>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
>>>> +		if (p->index)
>>>> +			return -EINVAL;
>>>> +		strscpy(p->name, vfd->name, sizeof(p->name));
>>>> +		p->type = V4L2_INPUT_TYPE_CAMERA;
>>>> +		return 0;
>>>> +	}
>>>> +
>>>>  	return ops->vidioc_enum_input(file, fh, p);
>>>>  }
>>>>  
>>>> @@ -1161,6 +1204,14 @@ static int v4l_enumoutput(const struct v4l2_ioctl_ops *ops,
>>>>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
>>>>  		p->capabilities |= V4L2_OUT_CAP_STD;
>>>>  
>>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
>>>> +		if (p->index)
>>>> +			return -EINVAL;
>>>> +		strscpy(p->name, vfd->name, sizeof(p->name));
>>>> +		p->type = V4L2_OUTPUT_TYPE_ANALOG;
>>>
>>> How about adding a new INPUT and OUTPUT types just for IO_MC device cap?
>>
>> V4L2_OUTPUT_TYPE_ANALOG is an old term that is in practice used for anything video,
>> except for TV modulators. I'm all in favor of changing this to:
>>
>> #define V4L2_OUTPUT_TYPE_VIDEO 2
>> #ifndef __KERNEL__
>> #define V4L2_OUTPUT_TYPE_ANALOG V4L2_OUTPUT_TYPE_VIDEO
>> #endif
>>
>> in videodev2.h, if others agree with that. But that can be done in a separate
>> follow-up patch since this needs to be adapted throughout the kernel & documentation.
>>
>> The same is true for V4L2_INPUT_TYPE_CAMERA: in practice it's used for any video,
>> except TV tuners.
> 
> My point was rather that here, we don't know what kind of device really is
> the source (or the sink) of the data path. Having a designated input and
> output type for that would be entirely appropriate.

But that's exactly what V4L2_OUTPUT_TYPE_ANALOG/V4L2_INPUT_TYPE_CAMERA means:
it's some kind of video, but we don't know what.

That's why these names are so misleading: they suggest a particular type,
but in reality they don't.

So V4L2_IN/OUTPUT_TYPE_VIDEO is what you want for MC inputs/outputs, but that's
just an alias for V4L2_INPUT_TYPE_CAMERA/V4L2_OUTPUT_TYPE_ANALOG.

Regards,

	Hans

> 
> Although if the user gets a misleading value using an interface that
> (s)he's not supposed to use to begin with, I guess I'd fine with that as
> well.
>
Sakari Ailus March 9, 2020, 2:22 p.m. UTC | #6
On Mon, Mar 09, 2020 at 03:10:36PM +0100, Hans Verkuil wrote:
> On 3/9/20 2:56 PM, Sakari Ailus wrote:
> > Hi Hans,
> > 
> > On Mon, Mar 09, 2020 at 02:53:15PM +0100, Hans Verkuil wrote:
> >> On 3/9/20 2:47 PM, Sakari Ailus wrote:
> >>> Hi Niklas,
> >>>
> >>> Thanks for the update!
> >>>
> >>> On Fri, Mar 06, 2020 at 05:39:33PM +0100, Niklas Söderlund wrote:
> >>>> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> >>>>
> >>>> Add a video device capability flag to indicate that its inputs and/or
> >>>> outputs are controlled by the Media Controller instead of the V4L2 API.
> >>>> When this flag is set, ioctl for enum inputs and outputs are
> >>>> automatically enabled and programmed to call a helper function.
> >>>>
> >>>> Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
> >>>> Signed-off-by: Helen Koike <helen.koike@collabora.com>
> >>>> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> >>>> ---
> >>>> * Changes since v3
> >>>> - Update documentation for V4L2_CAP_IO_MC
> >>>> - Only enable VIDIOC_{G,S}_{INPUT,OUTPUT} if V4L2_CAP_IO_MC is set
> >>>>   (instead of unconditionally)
> >>>> - Merge v4l2_ioctl_enum_input_mc() into v4l_enuminput()
> >>>> - Merge v4l2_ioctl_enum_output_mc() into v4l_enumoutput()
> >>>>
> >>>> * Changes since v2
> >>>> - Merged the two patches touching V4L2 core stuff to a single patch.
> >>>> - Updated documentation for V4L2_CAP_IO_MC
> >>>> - Added is_io_mc bool in determine_valid_ioctls()
> >>>> - Folded or moved code closer to where it's used
> >>>> - Remove unneeded memset()
> >>>> - Use strscpy() instead of strlcpy()
> >>>> ---
> >>>>  .../media/uapi/v4l/vidioc-querycap.rst        |  6 ++
> >>>>  .../media/videodev2.h.rst.exceptions          |  1 +
> >>>>  drivers/media/v4l2-core/v4l2-dev.c            | 25 ++++++--
> >>>>  drivers/media/v4l2-core/v4l2-ioctl.c          | 57 +++++++++++++++++--
> >>>>  include/uapi/linux/videodev2.h                |  2 +
> >>>>  5 files changed, 81 insertions(+), 10 deletions(-)
> >>>>
> >>>> diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> >>>> index 5f9930195d624c73..497a6aa2cbebad71 100644
> >>>> --- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
> >>>> +++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> >>>> @@ -264,6 +264,12 @@ specification the ioctl returns an ``EINVAL`` error code.
> >>>>      * - ``V4L2_CAP_TOUCH``
> >>>>        - 0x10000000
> >>>>        - This is a touch device.
> >>>> +    * - ``V4L2_CAP_IO_MC``
> >>>> +      - 0x20000000
> >>>> +      - There is only one input and/or output seen from userspace. The whole
> >>>> +        video topology configuration, including which I/O entity is routed to
> >>>> +        the input/output, is configured by userspace via the Media Controller.
> >>>> +        See :ref:`media_controller`.
> >>>>      * - ``V4L2_CAP_DEVICE_CAPS``
> >>>>        - 0x80000000
> >>>>        - The driver fills the ``device_caps`` field. This capability can
> >>>> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
> >>>> index cb6ccf91776e6b56..a625fb90e3a989a7 100644
> >>>> --- a/Documentation/media/videodev2.h.rst.exceptions
> >>>> +++ b/Documentation/media/videodev2.h.rst.exceptions
> >>>> @@ -176,6 +176,7 @@ replace define V4L2_CAP_STREAMING device-capabilities
> >>>>  replace define V4L2_CAP_META_OUTPUT device-capabilities
> >>>>  replace define V4L2_CAP_DEVICE_CAPS device-capabilities
> >>>>  replace define V4L2_CAP_TOUCH device-capabilities
> >>>> +replace define V4L2_CAP_IO_MC device-capabilities
> >>>>  
> >>>>  # V4L2 pix flags
> >>>>  replace define V4L2_PIX_FMT_PRIV_MAGIC :c:type:`v4l2_pix_format`
> >>>> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> >>>> index 97b6a3af13614639..a593ea0598b551b4 100644
> >>>> --- a/drivers/media/v4l2-core/v4l2-dev.c
> >>>> +++ b/drivers/media/v4l2-core/v4l2-dev.c
> >>>> @@ -552,6 +552,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
> >>>>  		       (vdev->device_caps & meta_caps);
> >>>>  	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
> >>>>  	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
> >>>> +	bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
> >>>>  
> >>>>  	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
> >>>>  
> >>>> @@ -725,9 +726,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
> >>>>  		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
> >>>>  		if (is_rx) {
> >>>>  			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
> >>>> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> >>>> -			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> >>>> -			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> >>>> +			if (is_io_mc) {
> >>>> +				set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
> >>>> +				set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
> >>>> +				set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
> >>>> +			} else {
> >>>> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> >>>> +				SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> >>>> +				SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> >>>> +			}
> >>>>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
> >>>>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
> >>>>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
> >>>> @@ -735,9 +742,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
> >>>>  			SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
> >>>>  		}
> >>>>  		if (is_tx) {
> >>>> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
> >>>> -			SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
> >>>> -			SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
> >>>> +			if (is_io_mc) {
> >>>> +				set_bit(_IOC_NR(VIDIOC_ENUMOUTPUT), valid_ioctls);
> >>>> +				set_bit(_IOC_NR(VIDIOC_G_OUTPUT), valid_ioctls);
> >>>> +				set_bit(_IOC_NR(VIDIOC_S_OUTPUT), valid_ioctls);
> >>>> +			} else {
> >>>> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
> >>>> +				SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
> >>>> +				SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
> >>>> +			}
> >>>>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
> >>>>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
> >>>>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
> >>>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> >>>> index fbcc7a20eedf553a..58e9e728f0a7aa4b 100644
> >>>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> >>>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> >>>> @@ -1085,6 +1085,32 @@ static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
> >>>>  	return ret;
> >>>>  }
> >>>>  
> >>>> +static int v4l_g_input(const struct v4l2_ioctl_ops *ops,
> >>>> +		       struct file *file, void *fh, void *arg)
> >>>> +{
> >>>> +	struct video_device *vfd = video_devdata(file);
> >>>> +
> >>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> >>>> +		*(unsigned int *)arg = 0;
> >>>> +		return 0;
> >>>> +	}
> >>>> +
> >>>> +	return ops->vidioc_g_input(file, fh, arg);
> >>>> +}
> >>>> +
> >>>> +static int v4l_g_output(const struct v4l2_ioctl_ops *ops,
> >>>> +		       struct file *file, void *fh, void *arg)
> >>>> +{
> >>>> +	struct video_device *vfd = video_devdata(file);
> >>>> +
> >>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> >>>> +		*(unsigned int *)arg = 0;
> >>>> +		return 0;
> >>>> +	}
> >>>> +
> >>>> +	return ops->vidioc_g_output(file, fh, arg);
> >>>> +}
> >>>> +
> >>>>  static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
> >>>>  				struct file *file, void *fh, void *arg)
> >>>>  {
> >>>> @@ -1094,12 +1120,21 @@ static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
> >>>>  	ret = v4l_enable_media_source(vfd);
> >>>>  	if (ret)
> >>>>  		return ret;
> >>>> +
> >>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
> >>>> +		return  *(unsigned int *)arg ? -EINVAL : 0;
> >>>> +
> >>>>  	return ops->vidioc_s_input(file, fh, *(unsigned int *)arg);
> >>>>  }
> >>>>  
> >>>>  static int v4l_s_output(const struct v4l2_ioctl_ops *ops,
> >>>>  				struct file *file, void *fh, void *arg)
> >>>>  {
> >>>> +	struct video_device *vfd = video_devdata(file);
> >>>> +
> >>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
> >>>> +		return  *(unsigned int *)arg ? -EINVAL : 0;
> >>>
> >>> The type is int, not unsigned int. The same on the rest above.
> >>>
> >>>> +
> >>>>  	return ops->vidioc_s_output(file, fh, *(unsigned int *)arg);
> >>>>  }
> >>>>  
> >>>> @@ -1143,6 +1178,14 @@ static int v4l_enuminput(const struct v4l2_ioctl_ops *ops,
> >>>>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
> >>>>  		p->capabilities |= V4L2_IN_CAP_STD;
> >>>>  
> >>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> >>>> +		if (p->index)
> >>>> +			return -EINVAL;
> >>>> +		strscpy(p->name, vfd->name, sizeof(p->name));
> >>>> +		p->type = V4L2_INPUT_TYPE_CAMERA;
> >>>> +		return 0;
> >>>> +	}
> >>>> +
> >>>>  	return ops->vidioc_enum_input(file, fh, p);
> >>>>  }
> >>>>  
> >>>> @@ -1161,6 +1204,14 @@ static int v4l_enumoutput(const struct v4l2_ioctl_ops *ops,
> >>>>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
> >>>>  		p->capabilities |= V4L2_OUT_CAP_STD;
> >>>>  
> >>>> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> >>>> +		if (p->index)
> >>>> +			return -EINVAL;
> >>>> +		strscpy(p->name, vfd->name, sizeof(p->name));
> >>>> +		p->type = V4L2_OUTPUT_TYPE_ANALOG;
> >>>
> >>> How about adding a new INPUT and OUTPUT types just for IO_MC device cap?
> >>
> >> V4L2_OUTPUT_TYPE_ANALOG is an old term that is in practice used for anything video,
> >> except for TV modulators. I'm all in favor of changing this to:
> >>
> >> #define V4L2_OUTPUT_TYPE_VIDEO 2
> >> #ifndef __KERNEL__
> >> #define V4L2_OUTPUT_TYPE_ANALOG V4L2_OUTPUT_TYPE_VIDEO
> >> #endif
> >>
> >> in videodev2.h, if others agree with that. But that can be done in a separate
> >> follow-up patch since this needs to be adapted throughout the kernel & documentation.
> >>
> >> The same is true for V4L2_INPUT_TYPE_CAMERA: in practice it's used for any video,
> >> except TV tuners.
> > 
> > My point was rather that here, we don't know what kind of device really is
> > the source (or the sink) of the data path. Having a designated input and
> > output type for that would be entirely appropriate.
> 
> But that's exactly what V4L2_OUTPUT_TYPE_ANALOG/V4L2_INPUT_TYPE_CAMERA means:
> it's some kind of video, but we don't know what.

The documentation says only that:

	Any non-modulator video output, for example Composite Video,
	S-Video, HDMI. The naming as ``_TYPE_ANALOG`` is historical,
	today we would have called it ``_TYPE_VIDEO``.

> 
> That's why these names are so misleading: they suggest a particular type,
> but in reality they don't.
> 
> So V4L2_IN/OUTPUT_TYPE_VIDEO is what you want for MC inputs/outputs, but that's
> just an alias for V4L2_INPUT_TYPE_CAMERA/V4L2_OUTPUT_TYPE_ANALOG.

Fine for me then.
Laurent Pinchart March 11, 2020, 1:10 a.m. UTC | #7
Hi Niklas,

Thank you for the patch.

On Fri, Mar 06, 2020 at 05:39:33PM +0100, Niklas Söderlund wrote:
> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> 
> Add a video device capability flag to indicate that its inputs and/or
> outputs are controlled by the Media Controller instead of the V4L2 API.
> When this flag is set, ioctl for enum inputs and outputs are
> automatically enabled and programmed to call a helper function.
> 
> Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
> Signed-off-by: Helen Koike <helen.koike@collabora.com>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
> * Changes since v3
> - Update documentation for V4L2_CAP_IO_MC
> - Only enable VIDIOC_{G,S}_{INPUT,OUTPUT} if V4L2_CAP_IO_MC is set
>   (instead of unconditionally)
> - Merge v4l2_ioctl_enum_input_mc() into v4l_enuminput()
> - Merge v4l2_ioctl_enum_output_mc() into v4l_enumoutput()
> 
> * Changes since v2
> - Merged the two patches touching V4L2 core stuff to a single patch.
> - Updated documentation for V4L2_CAP_IO_MC
> - Added is_io_mc bool in determine_valid_ioctls()
> - Folded or moved code closer to where it's used
> - Remove unneeded memset()
> - Use strscpy() instead of strlcpy()
> ---
>  .../media/uapi/v4l/vidioc-querycap.rst        |  6 ++
>  .../media/videodev2.h.rst.exceptions          |  1 +
>  drivers/media/v4l2-core/v4l2-dev.c            | 25 ++++++--
>  drivers/media/v4l2-core/v4l2-ioctl.c          | 57 +++++++++++++++++--
>  include/uapi/linux/videodev2.h                |  2 +
>  5 files changed, 81 insertions(+), 10 deletions(-)
> 
> diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> index 5f9930195d624c73..497a6aa2cbebad71 100644
> --- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
> +++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
> @@ -264,6 +264,12 @@ specification the ioctl returns an ``EINVAL`` error code.
>      * - ``V4L2_CAP_TOUCH``
>        - 0x10000000
>        - This is a touch device.
> +    * - ``V4L2_CAP_IO_MC``
> +      - 0x20000000
> +      - There is only one input and/or output seen from userspace. The whole
> +        video topology configuration, including which I/O entity is routed to
> +        the input/output, is configured by userspace via the Media Controller.

I would have disabled those ioctls instead, as they're completely
useless. Now that there's a V4L2_CAP_IO_MC flag, who will call those ?

I however don't care enough to block this, so

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> +        See :ref:`media_controller`.
>      * - ``V4L2_CAP_DEVICE_CAPS``
>        - 0x80000000
>        - The driver fills the ``device_caps`` field. This capability can
> diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
> index cb6ccf91776e6b56..a625fb90e3a989a7 100644
> --- a/Documentation/media/videodev2.h.rst.exceptions
> +++ b/Documentation/media/videodev2.h.rst.exceptions
> @@ -176,6 +176,7 @@ replace define V4L2_CAP_STREAMING device-capabilities
>  replace define V4L2_CAP_META_OUTPUT device-capabilities
>  replace define V4L2_CAP_DEVICE_CAPS device-capabilities
>  replace define V4L2_CAP_TOUCH device-capabilities
> +replace define V4L2_CAP_IO_MC device-capabilities
>  
>  # V4L2 pix flags
>  replace define V4L2_PIX_FMT_PRIV_MAGIC :c:type:`v4l2_pix_format`
> diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
> index 97b6a3af13614639..a593ea0598b551b4 100644
> --- a/drivers/media/v4l2-core/v4l2-dev.c
> +++ b/drivers/media/v4l2-core/v4l2-dev.c
> @@ -552,6 +552,7 @@ static void determine_valid_ioctls(struct video_device *vdev)
>  		       (vdev->device_caps & meta_caps);
>  	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
>  	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
> +	bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
>  
>  	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
>  
> @@ -725,9 +726,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>  		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
>  		if (is_rx) {
>  			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> -			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> -			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> +			if (is_io_mc) {
> +				set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
> +			} else {
> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
> +				SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
> +				SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
> +			}
>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
> @@ -735,9 +742,15 @@ static void determine_valid_ioctls(struct video_device *vdev)
>  			SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
>  		}
>  		if (is_tx) {
> -			SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
> -			SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
> -			SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
> +			if (is_io_mc) {
> +				set_bit(_IOC_NR(VIDIOC_ENUMOUTPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_G_OUTPUT), valid_ioctls);
> +				set_bit(_IOC_NR(VIDIOC_S_OUTPUT), valid_ioctls);
> +			} else {
> +				SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
> +				SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
> +				SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
> +			}
>  			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
>  			SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
>  			SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index fbcc7a20eedf553a..58e9e728f0a7aa4b 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1085,6 +1085,32 @@ static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
>  	return ret;
>  }
>  
> +static int v4l_g_input(const struct v4l2_ioctl_ops *ops,
> +		       struct file *file, void *fh, void *arg)
> +{
> +	struct video_device *vfd = video_devdata(file);
> +
> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> +		*(unsigned int *)arg = 0;
> +		return 0;
> +	}
> +
> +	return ops->vidioc_g_input(file, fh, arg);
> +}
> +
> +static int v4l_g_output(const struct v4l2_ioctl_ops *ops,
> +		       struct file *file, void *fh, void *arg)
> +{
> +	struct video_device *vfd = video_devdata(file);
> +
> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> +		*(unsigned int *)arg = 0;
> +		return 0;
> +	}
> +
> +	return ops->vidioc_g_output(file, fh, arg);
> +}
> +
>  static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
>  				struct file *file, void *fh, void *arg)
>  {
> @@ -1094,12 +1120,21 @@ static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
>  	ret = v4l_enable_media_source(vfd);
>  	if (ret)
>  		return ret;
> +
> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
> +		return  *(unsigned int *)arg ? -EINVAL : 0;
> +
>  	return ops->vidioc_s_input(file, fh, *(unsigned int *)arg);
>  }
>  
>  static int v4l_s_output(const struct v4l2_ioctl_ops *ops,
>  				struct file *file, void *fh, void *arg)
>  {
> +	struct video_device *vfd = video_devdata(file);
> +
> +	if (vfd->device_caps & V4L2_CAP_IO_MC)
> +		return  *(unsigned int *)arg ? -EINVAL : 0;
> +
>  	return ops->vidioc_s_output(file, fh, *(unsigned int *)arg);
>  }
>  
> @@ -1143,6 +1178,14 @@ static int v4l_enuminput(const struct v4l2_ioctl_ops *ops,
>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
>  		p->capabilities |= V4L2_IN_CAP_STD;
>  
> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> +		if (p->index)
> +			return -EINVAL;
> +		strscpy(p->name, vfd->name, sizeof(p->name));
> +		p->type = V4L2_INPUT_TYPE_CAMERA;
> +		return 0;
> +	}
> +
>  	return ops->vidioc_enum_input(file, fh, p);
>  }
>  
> @@ -1161,6 +1204,14 @@ static int v4l_enumoutput(const struct v4l2_ioctl_ops *ops,
>  	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
>  		p->capabilities |= V4L2_OUT_CAP_STD;
>  
> +	if (vfd->device_caps & V4L2_CAP_IO_MC) {
> +		if (p->index)
> +			return -EINVAL;
> +		strscpy(p->name, vfd->name, sizeof(p->name));
> +		p->type = V4L2_OUTPUT_TYPE_ANALOG;
> +		return 0;
> +	}
> +
>  	return ops->vidioc_enum_output(file, fh, p);
>  }
>  
> @@ -2678,10 +2729,8 @@ DEFINE_V4L_STUB_FUNC(expbuf)
>  DEFINE_V4L_STUB_FUNC(g_std)
>  DEFINE_V4L_STUB_FUNC(g_audio)
>  DEFINE_V4L_STUB_FUNC(s_audio)
> -DEFINE_V4L_STUB_FUNC(g_input)
>  DEFINE_V4L_STUB_FUNC(g_edid)
>  DEFINE_V4L_STUB_FUNC(s_edid)
> -DEFINE_V4L_STUB_FUNC(g_output)
>  DEFINE_V4L_STUB_FUNC(g_audout)
>  DEFINE_V4L_STUB_FUNC(s_audout)
>  DEFINE_V4L_STUB_FUNC(g_jpegcomp)
> @@ -2730,11 +2779,11 @@ static const struct v4l2_ioctl_info v4l2_ioctls[] = {
>  	IOCTL_INFO(VIDIOC_S_AUDIO, v4l_stub_s_audio, v4l_print_audio, INFO_FL_PRIO),
>  	IOCTL_INFO(VIDIOC_QUERYCTRL, v4l_queryctrl, v4l_print_queryctrl, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_queryctrl, id)),
>  	IOCTL_INFO(VIDIOC_QUERYMENU, v4l_querymenu, v4l_print_querymenu, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_querymenu, index)),
> -	IOCTL_INFO(VIDIOC_G_INPUT, v4l_stub_g_input, v4l_print_u32, 0),
> +	IOCTL_INFO(VIDIOC_G_INPUT, v4l_g_input, v4l_print_u32, 0),
>  	IOCTL_INFO(VIDIOC_S_INPUT, v4l_s_input, v4l_print_u32, INFO_FL_PRIO),
>  	IOCTL_INFO(VIDIOC_G_EDID, v4l_stub_g_edid, v4l_print_edid, INFO_FL_ALWAYS_COPY),
>  	IOCTL_INFO(VIDIOC_S_EDID, v4l_stub_s_edid, v4l_print_edid, INFO_FL_PRIO | INFO_FL_ALWAYS_COPY),
> -	IOCTL_INFO(VIDIOC_G_OUTPUT, v4l_stub_g_output, v4l_print_u32, 0),
> +	IOCTL_INFO(VIDIOC_G_OUTPUT, v4l_g_output, v4l_print_u32, 0),
>  	IOCTL_INFO(VIDIOC_S_OUTPUT, v4l_s_output, v4l_print_u32, INFO_FL_PRIO),
>  	IOCTL_INFO(VIDIOC_ENUMOUTPUT, v4l_enumoutput, v4l_print_enumoutput, INFO_FL_CLEAR(v4l2_output, index)),
>  	IOCTL_INFO(VIDIOC_G_AUDOUT, v4l_stub_g_audout, v4l_print_audioout, 0),
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 5f9357dcb0602126..c793263a37052856 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -487,6 +487,8 @@ struct v4l2_capability {
>  
>  #define V4L2_CAP_TOUCH                  0x10000000  /* Is a touch device */
>  
> +#define V4L2_CAP_IO_MC			0x20000000  /* Is input/output controlled by the media controller */
> +
>  #define V4L2_CAP_DEVICE_CAPS            0x80000000  /* sets device capabilities field */
>  
>  /*
diff mbox series

Patch

diff --git a/Documentation/media/uapi/v4l/vidioc-querycap.rst b/Documentation/media/uapi/v4l/vidioc-querycap.rst
index 5f9930195d624c73..497a6aa2cbebad71 100644
--- a/Documentation/media/uapi/v4l/vidioc-querycap.rst
+++ b/Documentation/media/uapi/v4l/vidioc-querycap.rst
@@ -264,6 +264,12 @@  specification the ioctl returns an ``EINVAL`` error code.
     * - ``V4L2_CAP_TOUCH``
       - 0x10000000
       - This is a touch device.
+    * - ``V4L2_CAP_IO_MC``
+      - 0x20000000
+      - There is only one input and/or output seen from userspace. The whole
+        video topology configuration, including which I/O entity is routed to
+        the input/output, is configured by userspace via the Media Controller.
+        See :ref:`media_controller`.
     * - ``V4L2_CAP_DEVICE_CAPS``
       - 0x80000000
       - The driver fills the ``device_caps`` field. This capability can
diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
index cb6ccf91776e6b56..a625fb90e3a989a7 100644
--- a/Documentation/media/videodev2.h.rst.exceptions
+++ b/Documentation/media/videodev2.h.rst.exceptions
@@ -176,6 +176,7 @@  replace define V4L2_CAP_STREAMING device-capabilities
 replace define V4L2_CAP_META_OUTPUT device-capabilities
 replace define V4L2_CAP_DEVICE_CAPS device-capabilities
 replace define V4L2_CAP_TOUCH device-capabilities
+replace define V4L2_CAP_IO_MC device-capabilities
 
 # V4L2 pix flags
 replace define V4L2_PIX_FMT_PRIV_MAGIC :c:type:`v4l2_pix_format`
diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c
index 97b6a3af13614639..a593ea0598b551b4 100644
--- a/drivers/media/v4l2-core/v4l2-dev.c
+++ b/drivers/media/v4l2-core/v4l2-dev.c
@@ -552,6 +552,7 @@  static void determine_valid_ioctls(struct video_device *vdev)
 		       (vdev->device_caps & meta_caps);
 	bool is_rx = vdev->vfl_dir != VFL_DIR_TX;
 	bool is_tx = vdev->vfl_dir != VFL_DIR_RX;
+	bool is_io_mc = vdev->device_caps & V4L2_CAP_IO_MC;
 
 	bitmap_zero(valid_ioctls, BASE_VIDIOC_PRIVATE);
 
@@ -725,9 +726,15 @@  static void determine_valid_ioctls(struct video_device *vdev)
 		SET_VALID_IOCTL(ops, VIDIOC_G_STD, vidioc_g_std);
 		if (is_rx) {
 			SET_VALID_IOCTL(ops, VIDIOC_QUERYSTD, vidioc_querystd);
-			SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
-			SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
-			SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
+			if (is_io_mc) {
+				set_bit(_IOC_NR(VIDIOC_ENUMINPUT), valid_ioctls);
+				set_bit(_IOC_NR(VIDIOC_G_INPUT), valid_ioctls);
+				set_bit(_IOC_NR(VIDIOC_S_INPUT), valid_ioctls);
+			} else {
+				SET_VALID_IOCTL(ops, VIDIOC_ENUMINPUT, vidioc_enum_input);
+				SET_VALID_IOCTL(ops, VIDIOC_G_INPUT, vidioc_g_input);
+				SET_VALID_IOCTL(ops, VIDIOC_S_INPUT, vidioc_s_input);
+			}
 			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDIO, vidioc_enumaudio);
 			SET_VALID_IOCTL(ops, VIDIOC_G_AUDIO, vidioc_g_audio);
 			SET_VALID_IOCTL(ops, VIDIOC_S_AUDIO, vidioc_s_audio);
@@ -735,9 +742,15 @@  static void determine_valid_ioctls(struct video_device *vdev)
 			SET_VALID_IOCTL(ops, VIDIOC_S_EDID, vidioc_s_edid);
 		}
 		if (is_tx) {
-			SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
-			SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
-			SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
+			if (is_io_mc) {
+				set_bit(_IOC_NR(VIDIOC_ENUMOUTPUT), valid_ioctls);
+				set_bit(_IOC_NR(VIDIOC_G_OUTPUT), valid_ioctls);
+				set_bit(_IOC_NR(VIDIOC_S_OUTPUT), valid_ioctls);
+			} else {
+				SET_VALID_IOCTL(ops, VIDIOC_ENUMOUTPUT, vidioc_enum_output);
+				SET_VALID_IOCTL(ops, VIDIOC_G_OUTPUT, vidioc_g_output);
+				SET_VALID_IOCTL(ops, VIDIOC_S_OUTPUT, vidioc_s_output);
+			}
 			SET_VALID_IOCTL(ops, VIDIOC_ENUMAUDOUT, vidioc_enumaudout);
 			SET_VALID_IOCTL(ops, VIDIOC_G_AUDOUT, vidioc_g_audout);
 			SET_VALID_IOCTL(ops, VIDIOC_S_AUDOUT, vidioc_s_audout);
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index fbcc7a20eedf553a..58e9e728f0a7aa4b 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1085,6 +1085,32 @@  static int v4l_querycap(const struct v4l2_ioctl_ops *ops,
 	return ret;
 }
 
+static int v4l_g_input(const struct v4l2_ioctl_ops *ops,
+		       struct file *file, void *fh, void *arg)
+{
+	struct video_device *vfd = video_devdata(file);
+
+	if (vfd->device_caps & V4L2_CAP_IO_MC) {
+		*(unsigned int *)arg = 0;
+		return 0;
+	}
+
+	return ops->vidioc_g_input(file, fh, arg);
+}
+
+static int v4l_g_output(const struct v4l2_ioctl_ops *ops,
+		       struct file *file, void *fh, void *arg)
+{
+	struct video_device *vfd = video_devdata(file);
+
+	if (vfd->device_caps & V4L2_CAP_IO_MC) {
+		*(unsigned int *)arg = 0;
+		return 0;
+	}
+
+	return ops->vidioc_g_output(file, fh, arg);
+}
+
 static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
 				struct file *file, void *fh, void *arg)
 {
@@ -1094,12 +1120,21 @@  static int v4l_s_input(const struct v4l2_ioctl_ops *ops,
 	ret = v4l_enable_media_source(vfd);
 	if (ret)
 		return ret;
+
+	if (vfd->device_caps & V4L2_CAP_IO_MC)
+		return  *(unsigned int *)arg ? -EINVAL : 0;
+
 	return ops->vidioc_s_input(file, fh, *(unsigned int *)arg);
 }
 
 static int v4l_s_output(const struct v4l2_ioctl_ops *ops,
 				struct file *file, void *fh, void *arg)
 {
+	struct video_device *vfd = video_devdata(file);
+
+	if (vfd->device_caps & V4L2_CAP_IO_MC)
+		return  *(unsigned int *)arg ? -EINVAL : 0;
+
 	return ops->vidioc_s_output(file, fh, *(unsigned int *)arg);
 }
 
@@ -1143,6 +1178,14 @@  static int v4l_enuminput(const struct v4l2_ioctl_ops *ops,
 	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
 		p->capabilities |= V4L2_IN_CAP_STD;
 
+	if (vfd->device_caps & V4L2_CAP_IO_MC) {
+		if (p->index)
+			return -EINVAL;
+		strscpy(p->name, vfd->name, sizeof(p->name));
+		p->type = V4L2_INPUT_TYPE_CAMERA;
+		return 0;
+	}
+
 	return ops->vidioc_enum_input(file, fh, p);
 }
 
@@ -1161,6 +1204,14 @@  static int v4l_enumoutput(const struct v4l2_ioctl_ops *ops,
 	if (is_valid_ioctl(vfd, VIDIOC_S_STD))
 		p->capabilities |= V4L2_OUT_CAP_STD;
 
+	if (vfd->device_caps & V4L2_CAP_IO_MC) {
+		if (p->index)
+			return -EINVAL;
+		strscpy(p->name, vfd->name, sizeof(p->name));
+		p->type = V4L2_OUTPUT_TYPE_ANALOG;
+		return 0;
+	}
+
 	return ops->vidioc_enum_output(file, fh, p);
 }
 
@@ -2678,10 +2729,8 @@  DEFINE_V4L_STUB_FUNC(expbuf)
 DEFINE_V4L_STUB_FUNC(g_std)
 DEFINE_V4L_STUB_FUNC(g_audio)
 DEFINE_V4L_STUB_FUNC(s_audio)
-DEFINE_V4L_STUB_FUNC(g_input)
 DEFINE_V4L_STUB_FUNC(g_edid)
 DEFINE_V4L_STUB_FUNC(s_edid)
-DEFINE_V4L_STUB_FUNC(g_output)
 DEFINE_V4L_STUB_FUNC(g_audout)
 DEFINE_V4L_STUB_FUNC(s_audout)
 DEFINE_V4L_STUB_FUNC(g_jpegcomp)
@@ -2730,11 +2779,11 @@  static const struct v4l2_ioctl_info v4l2_ioctls[] = {
 	IOCTL_INFO(VIDIOC_S_AUDIO, v4l_stub_s_audio, v4l_print_audio, INFO_FL_PRIO),
 	IOCTL_INFO(VIDIOC_QUERYCTRL, v4l_queryctrl, v4l_print_queryctrl, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_queryctrl, id)),
 	IOCTL_INFO(VIDIOC_QUERYMENU, v4l_querymenu, v4l_print_querymenu, INFO_FL_CTRL | INFO_FL_CLEAR(v4l2_querymenu, index)),
-	IOCTL_INFO(VIDIOC_G_INPUT, v4l_stub_g_input, v4l_print_u32, 0),
+	IOCTL_INFO(VIDIOC_G_INPUT, v4l_g_input, v4l_print_u32, 0),
 	IOCTL_INFO(VIDIOC_S_INPUT, v4l_s_input, v4l_print_u32, INFO_FL_PRIO),
 	IOCTL_INFO(VIDIOC_G_EDID, v4l_stub_g_edid, v4l_print_edid, INFO_FL_ALWAYS_COPY),
 	IOCTL_INFO(VIDIOC_S_EDID, v4l_stub_s_edid, v4l_print_edid, INFO_FL_PRIO | INFO_FL_ALWAYS_COPY),
-	IOCTL_INFO(VIDIOC_G_OUTPUT, v4l_stub_g_output, v4l_print_u32, 0),
+	IOCTL_INFO(VIDIOC_G_OUTPUT, v4l_g_output, v4l_print_u32, 0),
 	IOCTL_INFO(VIDIOC_S_OUTPUT, v4l_s_output, v4l_print_u32, INFO_FL_PRIO),
 	IOCTL_INFO(VIDIOC_ENUMOUTPUT, v4l_enumoutput, v4l_print_enumoutput, INFO_FL_CLEAR(v4l2_output, index)),
 	IOCTL_INFO(VIDIOC_G_AUDOUT, v4l_stub_g_audout, v4l_print_audioout, 0),
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 5f9357dcb0602126..c793263a37052856 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -487,6 +487,8 @@  struct v4l2_capability {
 
 #define V4L2_CAP_TOUCH                  0x10000000  /* Is a touch device */
 
+#define V4L2_CAP_IO_MC			0x20000000  /* Is input/output controlled by the media controller */
+
 #define V4L2_CAP_DEVICE_CAPS            0x80000000  /* sets device capabilities field */
 
 /*