Re: [PATCH v6 05/12] media: microchip-isc: add driver documentation

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Low] The newly added documentation incorrectly directs userspace developers to `atmel-isc-media.h`, which is not an exported UAPI header.
- [Low] Mismatch between documented and implemented minimum value for White Balance offset controls.
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commit 71e9f4b43ec565af48fe0deff5792741daea5496
Author: Balakrishnan Sambath <balakrishnan.s@microchip.com>

media: microchip-isc: add driver documentation

This commit adds UAPI documentation for the Microchip ISC and XISC drivers.
It covers driver topology, supported formats, controls, the AWB algorithm,
the gamma table layout, and custom controls.

> diff --git a/Documentation/userspace-api/media/drivers/microchip-isc.rst b/Documentation/userspace-api/media/drivers/microchip-isc.rst
> new file mode 100644
> index 0000000000000..69c7672e122a9
> --- /dev/null
> +++ b/Documentation/userspace-api/media/drivers/microchip-isc.rst

[ ... ]

> +SAMA7G5/SAM9X7 add:
> +
> +* ``V4L2_CID_HUE``: -180..180 degrees
> +* ``V4L2_CID_SATURATION``: 0..127, default 16 (Q4 fixed-point, 16 = 1.0x)
> +
> +Custom controls (defined in ``atmel-isc-media.h``):

[Severity: Low]
Will this correctly guide userspace application developers?

The documentation points users to atmel-isc-media.h for custom control
definitions. However, because atmel-isc-media.h is located in include/linux/
rather than include/uapi/linux/, it is an internal kernel header and will
not be exported by make headers_install.

> +
> +* ``ISC_CID_R_GAIN``, ``ISC_CID_B_GAIN``, ``ISC_CID_GR_GAIN``,
> +  ``ISC_CID_GB_GAIN``: WB gains, 0..8191, Q2.9 (512 = 1.0x)
> +* ``ISC_CID_R_OFFSET``, ``ISC_CID_B_OFFSET``, ``ISC_CID_GR_OFFSET``,
> +  ``ISC_CID_GB_OFFSET``: WB offsets, -4096..4095

[Severity: Low]
Does the minimum value for the WB offset controls match the driver
implementation?

The documentation states the range is -4096 to 4095, but looking at
drivers/media/platform/microchip/microchip-isc-base.c, the ISC_CTRL_OFF
macro sets the .min value to -4095:

drivers/media/platform/microchip/microchip-isc-base.c:
#define ISC_CTRL_OFF(_id, _name) \
    ...
    .min = -4095, \
    ...

Could this be updated so the documentation matches the off-by-one difference
in the source?

> +
> +Pipeline
> +--------

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260603-microchip-isc-fixes-v6-0-8c3d7474a768@microchip.com?part=5