Re: [PATCH] [RFC PATCH] staging: media: atomisp: remove redundant ov2722_startup() helper

From: Greg Kroah-Hartman

Date: Sun Aug 09 2026 - 14:19:03 EST


On Sun, Aug 09, 2026 at 11:31:05PM +0530, Mohit Mishra wrote:
> In atomisp-ov2722.c, ov2722_startup() was invoked inside
> ov2722_set_fmt() to program sensor hardware registers during format
> negotiation, accompanied by a "TODO: remove it" comment.
>
> Standard V4L2 subdevice drivers do not program hardware registers during
> .set_fmt(), but defer hardware register configuration to stream start
> (.s_stream(1)).
>
> This patch:
> 1. Removes the ov2722_startup() helper function and its TODO comment.
> 2. Refactors register initialization into a static
> ov2722_startup_registers() helper.
> 3. Moves sensor software reset and resolution register array configuration
> into ov2722_s_stream() when enable == 1.
> 4. Preserves the PMIC power-cycle retry loop on startup failure inside
> ov2722_s_stream(1) to maintain hardware fault-tolerance for AtomISP
> tablets.
> 5. Updates ov2722_set_fmt() to purely update internal software state.
>
> BEHAVIORAL RISK & UNTESTED NOTICE:
> This is a functional timing change. Deferring hardware register writes to
> .s_stream(1) has not been tested on physical Intel AtomISP hardware.
> Submitted as RFC for review by AtomISP maintainers (Hans de Goede,
> Mauro Carvalho Chehab).

I would recommend doing changes like this ONLY if you have the hardware
to test it with.

And did you forget an Assisted-by: tag?

thanks,

greg k-h