Re: [PATCH v2 7/9] media: docs: add doc for the stm32 dma2d driver

[Hans Verkuil]

On 15/07/2021 11:24, dillon.minfei@xxxxxxxxx wrote:
> From: Dillon Min <dillon.minfei@xxxxxxxxx>
> 
> add stm32-uapi.rst for stm32's dma2d driver, explain the details of ioctl
> V4L2_CID_DMA2D_R2M_MODE, V4L2_CID_DMA2D_R2M_COLOR.
> 
> Signed-off-by: Dillon Min <dillon.minfei@xxxxxxxxx>
> ---
> v2: introduce the stm32-uapi.rst to explain the detail of dma2d's ioctl.
> 
>  .../userspace-api/media/drivers/index.rst          |  1 +
>  .../userspace-api/media/drivers/stm32-uapi.rst     | 22 ++++++++++++++++++++++
>  2 files changed, 23 insertions(+)
>  create mode 100644 Documentation/userspace-api/media/drivers/stm32-uapi.rst
> 
> diff --git a/Documentation/userspace-api/media/drivers/index.rst b/Documentation/userspace-api/media/drivers/index.rst
> index 12e3c512d718..ce42915d48f4 100644
> --- a/Documentation/userspace-api/media/drivers/index.rst
> +++ b/Documentation/userspace-api/media/drivers/index.rst
> @@ -38,4 +38,5 @@ For more details see the file COPYING in the source distribution of Linux.
>  	max2175
>  	meye-uapi
>  	omap3isp-uapi
> +	stm32-uapi
>  	uvcvideo
> diff --git a/Documentation/userspace-api/media/drivers/stm32-uapi.rst b/Documentation/userspace-api/media/drivers/stm32-uapi.rst
> new file mode 100644
> index 000000000000..d7a4f717387d
> --- /dev/null
> +++ b/Documentation/userspace-api/media/drivers/stm32-uapi.rst
> @@ -0,0 +1,22 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +
> +STM32 Chrom-Art 2D Graphics Accelerator unit (DMA2D) driver
> +================================================
> +
> +The DMA2D driver implements the following driver-specific controls:
> +
> +``V4L2_CID_DMA2D_R2M_MODE``

Please mention the control type as well.

> +-------------------------
> +    Enable/Disable the Register-To-Memory mode, filling a part or the
> +    whole of a destination image with a specific color.
> +
> +    1 for enable, 0 for disable.
> +
> +``V4L2_CID_DMA2D_R2M_COLOR``

Ditto.

> +-------------------------------
> +    Set the color to fill a part or the whole of a destination image.
> +    only used under Register-To-Memory mode, to set the DMA2D_OCOLR register
> +    (RED, GREEN, BLUE) which is:

Here you mention RGB only,

> +
> +    31 .. 24    23 .. 16  15 .. 8     7 .. 0
> +    ALPHA[7:0]  RED[7:0]  GREEN[7:0]  BLUE[7:0]

but here you also mention Alpha. So which is it?

See also my review of patch 9/9.

> 

I'm getting some warnings building this doc:

Documentation/media/userspace-api/drivers/stm32-uapi.rst:4: WARNING: Title underline too short.

STM32 Chrom-Art 2D Graphics Accelerator unit (DMA2D) driver
================================================
Documentation/media/userspace-api/drivers/stm32-uapi.rst:9: WARNING: Title underline too short.

``V4L2_CID_DMA2D_R2M_MODE``
-------------------------

Regards,

	Hans