Re: [PATCH v7 4/7] media: platform: amd: isp4 subdev and firmware loading handling added

[Du, Bin]

On 1/15/2026 5:07 AM, Sakari Ailus wrote:
> Hi Bin,
>
> On Wed, Jan 14, 2026 at 06:34:34PM +0800, Du, Bin wrote:
> > > The increment could probably be expressed as seen &= ~BIT(i).
> >
> > Quoted below is Sultan's reply regarding this, Would it be acceptable to
> > leave it unchanged?
> >
> > "Yes it can be, but it adds several more instructions before the loop body,
> > without any improvement to the loop body (the sarx in the loop body is
> > replaced
> > by andn). The right shift trick is faster and this is a hot path (IRQ
> > handler).
>
> Please see my reply to Sultan.

Yes, I appreciate the instructive ideas from you and Sultan.

> > > > +static int isp4sd_sdev_link_validate(struct media_link *link)
> > > > +{
> > > > +	return 0;
> > >
> > > Uh-oh.
> > >
> > > What is actually being configured via the sub-device? There is no device
> > > node either, is there? Are there plans for future developments, apart from
> > > possibly making the ISP and the sensor controllable by the host?
> >
> > Yes, you are correct. For the first version, no device node and
> > configuration for the sub-device now. Possible future development plan is
> > under internal discussion.
>
> You can drop these for now.

Sure, will remove these now and reintroduce them when they're needed in 
the future.

--
Regards,
Bin