diff mbox series

[RFC,4/4] media: v4l: ctrl: Add V4L2_CID_CONFIG_MODEL control

Message ID 20241011075535.588140-5-sakari.ailus@linux.intel.com (mailing list archive)
State New
Headers show
Series Sub-device configuration models | expand

Commit Message

Sakari Ailus Oct. 11, 2024, 7:55 a.m. UTC
Add the V4L2_CID_CONFIG_MODEL control for the configuration model.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 .../userspace-api/media/v4l/ext-ctrls-image-process.rst      | 4 ++++
 .../userspace-api/media/v4l/subdev-config-model.rst          | 2 ++
 drivers/media/v4l2-core/v4l2-ctrls-defs.c                    | 5 +++++
 include/uapi/linux/v4l2-controls.h                           | 3 +++
 4 files changed, 14 insertions(+)

Comments

Laurent Pinchart Oct. 22, 2024, 7:42 p.m. UTC | #1
Hi Sakari,

Thank you for the patch.

On Fri, Oct 11, 2024 at 10:55:35AM +0300, Sakari Ailus wrote:
> Add the V4L2_CID_CONFIG_MODEL control for the configuration model.
> 
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  .../userspace-api/media/v4l/ext-ctrls-image-process.rst      | 4 ++++
>  .../userspace-api/media/v4l/subdev-config-model.rst          | 2 ++
>  drivers/media/v4l2-core/v4l2-ctrls-defs.c                    | 5 +++++
>  include/uapi/linux/v4l2-controls.h                           | 3 +++
>  4 files changed, 14 insertions(+)
> 
> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> index 27803dca8d3e..928e8e3eed7f 100644
> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> @@ -55,3 +55,7 @@ Image Process Control IDs
>      control value divided by e.g. 0x100, meaning that to get no
>      digital gain the control value needs to be 0x100. The no-gain
>      configuration is also typically the default.
> +
> +``V4L2_CID_CONFIG_MODEL (bitmask)``
> +    Which configuration models the sub-device supports. Please see
> +    :ref:`media_subdev_config_model`.
> diff --git a/Documentation/userspace-api/media/v4l/subdev-config-model.rst b/Documentation/userspace-api/media/v4l/subdev-config-model.rst
> index 8ec801998f5f..d4ae921b69c8 100644
> --- a/Documentation/userspace-api/media/v4l/subdev-config-model.rst
> +++ b/Documentation/userspace-api/media/v4l/subdev-config-model.rst
> @@ -1,5 +1,7 @@
>  .. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
>  
> +.. _media_subdev_config_model:
> +

This could be moved to 3/4.

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

>  Sub-device configuration models
>  ===============================
>  
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> index 6b9188a4a220..378657a52cd5 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> @@ -1167,6 +1167,7 @@ const char *v4l2_ctrl_get_name(u32 id)
>  	case V4L2_CID_TEST_PATTERN:		return "Test Pattern";
>  	case V4L2_CID_DEINTERLACING_MODE:	return "Deinterlacing Mode";
>  	case V4L2_CID_DIGITAL_GAIN:		return "Digital Gain";
> +	case V4L2_CID_CONFIG_MODEL:		return "Sub-device configuration model";
>  
>  	/* DV controls */
>  	/* Keep the order of the 'case's the same as in v4l2-controls.h! */
> @@ -1489,6 +1490,10 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
>  	case V4L2_CID_DV_RX_POWER_PRESENT:
>  		*type = V4L2_CTRL_TYPE_BITMASK;
>  		break;
> +	case V4L2_CID_CONFIG_MODEL:
> +		*flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +		*type = V4L2_CTRL_TYPE_BITMASK;
> +		break;
>  	case V4L2_CID_MIN_BUFFERS_FOR_CAPTURE:
>  	case V4L2_CID_MIN_BUFFERS_FOR_OUTPUT:
>  		*type = V4L2_CTRL_TYPE_INTEGER;
> diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> index 974fd254e573..0152240229ab 100644
> --- a/include/uapi/linux/v4l2-controls.h
> +++ b/include/uapi/linux/v4l2-controls.h
> @@ -1225,6 +1225,9 @@ enum v4l2_jpeg_chroma_subsampling {
>  #define V4L2_CID_TEST_PATTERN			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 3)
>  #define V4L2_CID_DEINTERLACING_MODE		(V4L2_CID_IMAGE_PROC_CLASS_BASE + 4)
>  #define V4L2_CID_DIGITAL_GAIN			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 5)
> +#define V4L2_CID_CONFIG_MODEL			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 6)
> +
> +#define V4L2_CID_CONFIG_MODEL_COMMON_RAW	(1ULL << 0)
>  
>  /*  DV-class control IDs defined by V4L2 */
>  #define V4L2_CID_DV_CLASS_BASE			(V4L2_CTRL_CLASS_DV | 0x900)
Sakari Ailus Nov. 13, 2024, 7:37 a.m. UTC | #2
Hi Laurent,

On Tue, Oct 22, 2024 at 10:42:53PM +0300, Laurent Pinchart wrote:
> > index 8ec801998f5f..d4ae921b69c8 100644
> > --- a/Documentation/userspace-api/media/v4l/subdev-config-model.rst
> > +++ b/Documentation/userspace-api/media/v4l/subdev-config-model.rst
> > @@ -1,5 +1,7 @@
> >  .. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
> >  
> > +.. _media_subdev_config_model:
> > +
> 
> This could be moved to 3/4.

Yes, that's where it belongs indeed.

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

Thanks!
Hans Verkuil Nov. 13, 2024, 8:03 a.m. UTC | #3
On 11/10/2024 09:55, Sakari Ailus wrote:
> Add the V4L2_CID_CONFIG_MODEL control for the configuration model.
> 
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  .../userspace-api/media/v4l/ext-ctrls-image-process.rst      | 4 ++++
>  .../userspace-api/media/v4l/subdev-config-model.rst          | 2 ++
>  drivers/media/v4l2-core/v4l2-ctrls-defs.c                    | 5 +++++
>  include/uapi/linux/v4l2-controls.h                           | 3 +++
>  4 files changed, 14 insertions(+)
> 
> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> index 27803dca8d3e..928e8e3eed7f 100644
> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> @@ -55,3 +55,7 @@ Image Process Control IDs
>      control value divided by e.g. 0x100, meaning that to get no
>      digital gain the control value needs to be 0x100. The no-gain
>      configuration is also typically the default.
> +
> +``V4L2_CID_CONFIG_MODEL (bitmask)``
> +    Which configuration models the sub-device supports. Please see
> +    :ref:`media_subdev_config_model`.

First of all the naming is confusing: since this is specific to sub-devices, it
should at least have 'SUBDEV' in the name. I first thought this reported the
model name or something like that, I'm not sure "configuration model" is a very
good name.

Secondly, is this supposed to be valid for all subdevices? Only for sensors?
Would an HDMI-to-CSI bridge qualify?

Thirdly, only V4L2_CID_CONFIG_MODEL_COMMON_RAW is defined right now. What other
models do you have in mind? What models can co-exist (since this is a bitmask)?

Finally, why choose a control for this? Should this perhaps be better done as
a field in media_entity_desc/media_v2_entity?

Regards,

	Hans

> diff --git a/Documentation/userspace-api/media/v4l/subdev-config-model.rst b/Documentation/userspace-api/media/v4l/subdev-config-model.rst
> index 8ec801998f5f..d4ae921b69c8 100644
> --- a/Documentation/userspace-api/media/v4l/subdev-config-model.rst
> +++ b/Documentation/userspace-api/media/v4l/subdev-config-model.rst
> @@ -1,5 +1,7 @@
>  .. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
>  
> +.. _media_subdev_config_model:
> +
>  Sub-device configuration models
>  ===============================
>  
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> index 6b9188a4a220..378657a52cd5 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> @@ -1167,6 +1167,7 @@ const char *v4l2_ctrl_get_name(u32 id)
>  	case V4L2_CID_TEST_PATTERN:		return "Test Pattern";
>  	case V4L2_CID_DEINTERLACING_MODE:	return "Deinterlacing Mode";
>  	case V4L2_CID_DIGITAL_GAIN:		return "Digital Gain";
> +	case V4L2_CID_CONFIG_MODEL:		return "Sub-device configuration model";

Start each word capitalized, just like all the other strings.

>  
>  	/* DV controls */
>  	/* Keep the order of the 'case's the same as in v4l2-controls.h! */
> @@ -1489,6 +1490,10 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
>  	case V4L2_CID_DV_RX_POWER_PRESENT:
>  		*type = V4L2_CTRL_TYPE_BITMASK;
>  		break;
> +	case V4L2_CID_CONFIG_MODEL:
> +		*flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +		*type = V4L2_CTRL_TYPE_BITMASK;
> +		break;
>  	case V4L2_CID_MIN_BUFFERS_FOR_CAPTURE:
>  	case V4L2_CID_MIN_BUFFERS_FOR_OUTPUT:
>  		*type = V4L2_CTRL_TYPE_INTEGER;
> diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> index 974fd254e573..0152240229ab 100644
> --- a/include/uapi/linux/v4l2-controls.h
> +++ b/include/uapi/linux/v4l2-controls.h
> @@ -1225,6 +1225,9 @@ enum v4l2_jpeg_chroma_subsampling {
>  #define V4L2_CID_TEST_PATTERN			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 3)
>  #define V4L2_CID_DEINTERLACING_MODE		(V4L2_CID_IMAGE_PROC_CLASS_BASE + 4)
>  #define V4L2_CID_DIGITAL_GAIN			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 5)
> +#define V4L2_CID_CONFIG_MODEL			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 6)
> +
> +#define V4L2_CID_CONFIG_MODEL_COMMON_RAW	(1ULL << 0)
>  
>  /*  DV-class control IDs defined by V4L2 */
>  #define V4L2_CID_DV_CLASS_BASE			(V4L2_CTRL_CLASS_DV | 0x900)
Sakari Ailus Nov. 13, 2024, 8:35 a.m. UTC | #4
Hi Hans,

Thank you for the review.

On Wed, Nov 13, 2024 at 09:03:57AM +0100, Hans Verkuil wrote:
> On 11/10/2024 09:55, Sakari Ailus wrote:
> > Add the V4L2_CID_CONFIG_MODEL control for the configuration model.
> > 
> > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> > ---
> >  .../userspace-api/media/v4l/ext-ctrls-image-process.rst      | 4 ++++
> >  .../userspace-api/media/v4l/subdev-config-model.rst          | 2 ++
> >  drivers/media/v4l2-core/v4l2-ctrls-defs.c                    | 5 +++++
> >  include/uapi/linux/v4l2-controls.h                           | 3 +++
> >  4 files changed, 14 insertions(+)
> > 
> > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> > index 27803dca8d3e..928e8e3eed7f 100644
> > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
> > @@ -55,3 +55,7 @@ Image Process Control IDs
> >      control value divided by e.g. 0x100, meaning that to get no
> >      digital gain the control value needs to be 0x100. The no-gain
> >      configuration is also typically the default.
> > +
> > +``V4L2_CID_CONFIG_MODEL (bitmask)``
> > +    Which configuration models the sub-device supports. Please see
> > +    :ref:`media_subdev_config_model`.
> 
> First of all the naming is confusing: since this is specific to sub-devices, it
> should at least have 'SUBDEV' in the name. I first thought this reported the

I don't object in principle, but the reason why I didn't add that in v1 was
the names would get quite long. Maybe V4L2_CID_SUBDEV_CFG_MODEL?

> model name or something like that, I'm not sure "configuration model" is a very
> good name.

Feel free to propose a different one. :-)

> 
> Secondly, is this supposed to be valid for all subdevices? Only for sensors?
> Would an HDMI-to-CSI bridge qualify?

I think it could but we should have a use case for it. In other words,
something we can't reasonably express using existing means. In this case
it's a number of interfaces and device type specific behaviour (see the 3rd
patch).

> 
> Thirdly, only V4L2_CID_CONFIG_MODEL_COMMON_RAW is defined right now. What other
> models do you have in mind? What models can co-exist (since this is a bitmask)?

We could have different raw camera models if needed. I don't have any
planned right now, though.

> 
> Finally, why choose a control for this? Should this perhaps be better done as
> a field in media_entity_desc/media_v2_entity?

I don't think it's a great fit. This is largely about V4L2 (to some but
lesser extent about MC) and we traditionally have avoided MC -> V4L2
dependencies.
Hans Verkuil Nov. 13, 2024, 12:26 p.m. UTC | #5
On 11/13/24 09:35, Sakari Ailus wrote:
> Hi Hans,
> 
> Thank you for the review.
> 
> On Wed, Nov 13, 2024 at 09:03:57AM +0100, Hans Verkuil wrote:
>> On 11/10/2024 09:55, Sakari Ailus wrote:
>>> Add the V4L2_CID_CONFIG_MODEL control for the configuration model.
>>>
>>> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
>>> ---
>>>  .../userspace-api/media/v4l/ext-ctrls-image-process.rst      | 4 ++++
>>>  .../userspace-api/media/v4l/subdev-config-model.rst          | 2 ++
>>>  drivers/media/v4l2-core/v4l2-ctrls-defs.c                    | 5 +++++
>>>  include/uapi/linux/v4l2-controls.h                           | 3 +++
>>>  4 files changed, 14 insertions(+)
>>>
>>> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
>>> index 27803dca8d3e..928e8e3eed7f 100644
>>> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
>>> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
>>> @@ -55,3 +55,7 @@ Image Process Control IDs
>>>      control value divided by e.g. 0x100, meaning that to get no
>>>      digital gain the control value needs to be 0x100. The no-gain
>>>      configuration is also typically the default.
>>> +
>>> +``V4L2_CID_CONFIG_MODEL (bitmask)``
>>> +    Which configuration models the sub-device supports. Please see
>>> +    :ref:`media_subdev_config_model`.
>>
>> First of all the naming is confusing: since this is specific to sub-devices, it
>> should at least have 'SUBDEV' in the name. I first thought this reported the
> 
> I don't object in principle, but the reason why I didn't add that in v1 was
> the names would get quite long. Maybe V4L2_CID_SUBDEV_CFG_MODEL?
> 
>> model name or something like that, I'm not sure "configuration model" is a very
>> good name.
> 
> Feel free to propose a different one. :-)

I would, if I understood what you intend to achieve :-)

> 
>>
>> Secondly, is this supposed to be valid for all subdevices? Only for sensors?
>> Would an HDMI-to-CSI bridge qualify?
> 
> I think it could but we should have a use case for it. In other words,
> something we can't reasonably express using existing means. In this case
> it's a number of interfaces and device type specific behaviour (see the 3rd
> patch).
> 
>>
>> Thirdly, only V4L2_CID_CONFIG_MODEL_COMMON_RAW is defined right now. What other
>> models do you have in mind? What models can co-exist (since this is a bitmask)?
> 
> We could have different raw camera models if needed. I don't have any
> planned right now, though.
> 
>>
>> Finally, why choose a control for this? Should this perhaps be better done as
>> a field in media_entity_desc/media_v2_entity?
> 
> I don't think it's a great fit. This is largely about V4L2 (to some but
> lesser extent about MC) and we traditionally have avoided MC -> V4L2
> dependencies.
> 

It sounds a bit like you want to report what Mauro calls a 'Profile'.

But I would expect the control to be an enum and not a bitmask, since I
would expect a device to fit just a single configuration mode, and not
multiple modes.

Also, V4L2_CID_CONFIG_MODEL_COMMON_RAW applies only to sensors, right?
So this should be V4L2_CID_CONFIG_MODEL_SENSOR_COMMON_RAW. But what is
common about it and what is raw about it?

Isn't it the case that pretty much all sensor drivers fall into this
category?

The only reason I see for this is if there are actually other configuration
modes going to be added in the near future.

What I am missing in this RFC is a high-level view of why it is needed and
how it is going to be used.

Perhaps I missed a discussion on linux-media?

Regards,

	Hans
diff mbox series

Patch

diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
index 27803dca8d3e..928e8e3eed7f 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-image-process.rst
@@ -55,3 +55,7 @@  Image Process Control IDs
     control value divided by e.g. 0x100, meaning that to get no
     digital gain the control value needs to be 0x100. The no-gain
     configuration is also typically the default.
+
+``V4L2_CID_CONFIG_MODEL (bitmask)``
+    Which configuration models the sub-device supports. Please see
+    :ref:`media_subdev_config_model`.
diff --git a/Documentation/userspace-api/media/v4l/subdev-config-model.rst b/Documentation/userspace-api/media/v4l/subdev-config-model.rst
index 8ec801998f5f..d4ae921b69c8 100644
--- a/Documentation/userspace-api/media/v4l/subdev-config-model.rst
+++ b/Documentation/userspace-api/media/v4l/subdev-config-model.rst
@@ -1,5 +1,7 @@ 
 .. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
 
+.. _media_subdev_config_model:
+
 Sub-device configuration models
 ===============================
 
diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
index 6b9188a4a220..378657a52cd5 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
@@ -1167,6 +1167,7 @@  const char *v4l2_ctrl_get_name(u32 id)
 	case V4L2_CID_TEST_PATTERN:		return "Test Pattern";
 	case V4L2_CID_DEINTERLACING_MODE:	return "Deinterlacing Mode";
 	case V4L2_CID_DIGITAL_GAIN:		return "Digital Gain";
+	case V4L2_CID_CONFIG_MODEL:		return "Sub-device configuration model";
 
 	/* DV controls */
 	/* Keep the order of the 'case's the same as in v4l2-controls.h! */
@@ -1489,6 +1490,10 @@  void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
 	case V4L2_CID_DV_RX_POWER_PRESENT:
 		*type = V4L2_CTRL_TYPE_BITMASK;
 		break;
+	case V4L2_CID_CONFIG_MODEL:
+		*flags |= V4L2_CTRL_FLAG_READ_ONLY;
+		*type = V4L2_CTRL_TYPE_BITMASK;
+		break;
 	case V4L2_CID_MIN_BUFFERS_FOR_CAPTURE:
 	case V4L2_CID_MIN_BUFFERS_FOR_OUTPUT:
 		*type = V4L2_CTRL_TYPE_INTEGER;
diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
index 974fd254e573..0152240229ab 100644
--- a/include/uapi/linux/v4l2-controls.h
+++ b/include/uapi/linux/v4l2-controls.h
@@ -1225,6 +1225,9 @@  enum v4l2_jpeg_chroma_subsampling {
 #define V4L2_CID_TEST_PATTERN			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 3)
 #define V4L2_CID_DEINTERLACING_MODE		(V4L2_CID_IMAGE_PROC_CLASS_BASE + 4)
 #define V4L2_CID_DIGITAL_GAIN			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 5)
+#define V4L2_CID_CONFIG_MODEL			(V4L2_CID_IMAGE_PROC_CLASS_BASE + 6)
+
+#define V4L2_CID_CONFIG_MODEL_COMMON_RAW	(1ULL << 0)
 
 /*  DV-class control IDs defined by V4L2 */
 #define V4L2_CID_DV_CLASS_BASE			(V4L2_CTRL_CLASS_DV | 0x900)