Re: [PATCH 0/8] media: Introduce V4L2 extensible parameters

[Keke Li <keke.li@amlogic.com>]

Hi Jacopo

On 2025/7/8 18:40, Jacopo Mondi wrote:
> [ EXTERNAL EMAIL ]
>
> Extensible parameters meta formats have been introduced in the Linux
> kernel v6.12 initially to support different revision of the RkISP1 ISP
> implemented in different SoC. In order to avoid breaking userspace
> everytime an ISP configuration block is added or modified in the uAPI
> these new formats, which are versionated and extensible by their
> definition have been introduced.
>
> See for reference:
> e9d05e9d5db1 ("media: uapi: rkisp1-config: Add extensible params format")
> 6c53a7b68c5d ("media: rkisp1: Implement extensible params support")
>
> The Amlogic C3 ISP driver followed shortly, introducing an extensible
> format for the ISP configuration:
>
> 6d406187ebc0 ("media: uapi: Add stats info and parameters buffer for C3 ISP")
>
> with a very similar, if not identical, implementation of the routines to
> validate and handle the ISP configuration in the ISP driver in the
> c3-isp-params.c file.
>
> fb2e135208f3 ("media: platform: Add C3 ISP driver")
>
> With the recent upstreaming attempt of the Mali C55 ISP driver from Dan,
> a third user of extensible parameters is going to be itroduced in the
> kernel, duplicating again in the driver the procedure for validating and
> handling the ISP configuration blocks
>
> https://patchwork.linuxtv.org/project/linux-media/patch/20250624-c55-v10-15-54f3d4196990@ideasonboard.com/
>
> To avoid duplicating again the validation routines and common types
> definition, this series introduces v4l2-params.c/.h for the kAPI
> and v4l2-extensible-params.h for the uAPI and re-organize the RkISP1
> and Amlogic C3 drivers to use the common types and the helper validation
> routines.
>
> If the here proposed approach is accepted, I propose to rebase the Mali
> C55 driver on top of this series, to use the new common types and
> helpers.
>
> I have been able to test this on RkISP1 but not on C3.
> Keke: would you be able to give this series a try and see what happens ?


I have tested this patch series on C3, the result is OK.

Thanks.

>
> Media CI pipeline:
> https://gitlab.freedesktop.org/linux-media/users/jmondi/-/pipelines/1465950
>
> Thanks
>    j
>
> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
> ---
> Jacopo Mondi (8):
>        media: uapi: Introduce V4L2 extensible params
>        media: uapi: Convert RkISP1 to V4L2 extensible params
>        media: uapi: Convert Amlogic C3 to V4L2 extensible params
>        media: Documentation: uapi: Add V4L2 extensible parameters
>        media: v4l2-common: Introduce v4l2-params.c
>        media: rkisp1: Use v4l2-params for validation
>        media: amlogic-c3: Use v4l2-params for validation
>        media: Documentation: kapi: Add v4l2 extensible parameters
>
>   Documentation/driver-api/media/v4l2-core.rst       |   1 +
>   Documentation/driver-api/media/v4l2-params.rst     |   5 +
>   .../media/v4l/extensible-parameters.rst            |  89 +++++
>   .../userspace-api/media/v4l/meta-formats.rst       |   1 +
>   MAINTAINERS                                        |  10 +
>   .../media/platform/amlogic/c3/isp/c3-isp-params.c  | 272 ++++++---------
>   .../media/platform/rockchip/rkisp1/rkisp1-params.c | 364 +++++++++------------
>   drivers/media/v4l2-core/Makefile                   |   3 +-
>   drivers/media/v4l2-core/v4l2-params.c              | 106 ++++++
>   include/media/v4l2-params.h                        | 166 ++++++++++
>   include/uapi/linux/media/amlogic/c3-isp-config.h   |  45 +--
>   include/uapi/linux/media/v4l2-extensible-params.h  | 106 ++++++
>   include/uapi/linux/rkisp1-config.h                 |  60 +---
>   13 files changed, 775 insertions(+), 453 deletions(-)
> ---
> base-commit: a8598c7de1bcd94461ca54c972efa9b4ea501fb9
> change-id: 20250701-extensible-parameters-validation-c831f7f5cc0b
>
> Best regards,
> --
> Jacopo Mondi <jacopo.mondi@ideasonboard.com>
>