Re: [PATCH v3 3/3] media: v4l2-common: Update v4l2_get_link_freq() documentation

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi Laurent,

On Thu, Aug 21, 2025 at 03:40:56PM +0300, Laurent Pinchart wrote:
> Hi Sakari,
> 
> Thank you for the patch.
> 
> On Thu, Aug 21, 2025 at 03:12:07PM +0300, Sakari Ailus wrote:
> > Document that v4l2_get_link_freq() obtains the link frequency primarily
> > by calling the get_mbus_config sub-device pad operation.
> > 
> > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> > ---
> >  include/media/v4l2-common.h | 8 +++++---
> >  1 file changed, 5 insertions(+), 3 deletions(-)
> > 
> > diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
> > index ab0ce8e605c3..c387deffbdd0 100644
> > --- a/include/media/v4l2-common.h
> > +++ b/include/media/v4l2-common.h
> > @@ -567,9 +567,11 @@ int v4l2_fill_pixfmt_mp(struct v4l2_pix_format_mplane *pixfmt, u32 pixelformat,
> >   *	 times two on D-PHY, 1 on parallel. 0 otherwise.
> >   *
> >   * This function is intended for obtaining the link frequency from the
> > - * transmitter sub-device's pad. It returns the link rate, either from the
> > - * V4L2_CID_LINK_FREQ control implemented by the transmitter, or value
> > - * calculated based on the V4L2_CID_PIXEL_RATE implemented by the transmitter.
> > + * transmitter sub-device's @pad. It returns the link rate, primarily obtained
> > + * through the get_mbus_config sub-device pad operation or secondarily through
> > + * either from the V4L2_CID_LINK_FREQ control implemented by the transmitter, or
> 
> "through either from" should be either "through either" or "either
> from".
> 
> > + * value calculated based on the V4L2_CID_PIXEL_RATE implemented by the
> > + * transmitter.
> 
> I think this can be clarified further:
> 
>  * This function obtains and returns the link frequency from the transmitter
>  * sub-device's pad. The link frequency is retrieved using the get_mbus_config
>  * sub-device pad operation. If this fails, the function falls back to obtaining
>  * the frequency either directly from the V4L2_CID_LINK_FREQ control if
>  * implemented by the transmitter, or by calculating it from the pixel rate
>  * obtained from the V4L2_CID_PIXEL_RATE control.
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Thanks. I'll use the text in v4.

-- 
Sakari Ailus