Re: [PATCH v3 07/15] media: qcom: camss: Capture VFE CSID dependency in a helper function

Laurent Pinchart
2023-08-28T19:40:45Z

On Mon, Aug 28, 2023 at 08:37:44PM +0100, Bryan O'Donoghue wrote:
> On 28/08/2023 19:47, Laurent Pinchart wrote:
> > Hi Bryan,
> >
> > Thank you for the patch.
> >
> > On Wed, Aug 23, 2023 at 11:44:36AM +0100, Bryan O'Donoghue wrote:
> >> From sdm845 onwards we need to ensure the VFE is powered on prior to
> >> switching on the CSID.
> >
> > Based on the discussions with Konrad in the mail thread, I would record
> > here the reason for this requirement.
> >
> > What happens if you unconditionally power up the VFE prior to switching
> > the CSID on ? Will this break something on platforms older than SDM845 ?
>
> vfe->power_count will bump and you will be fine.

Then maybe that would be a simpler solution than having a
device-specific power sequence ?

--
Regards,

Laurent Pinchart