Re: [PATCH v7 5/5] media: intel/ipu6: Obtain link frequency from a sub-device

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

Hi Laurent,

On Sun, Dec 15, 2024 at 07:08:32PM +0200, Laurent Pinchart wrote:
> Hi Sakari,
> 
> Thank you for the patch.

Thank you for the review. I asked you to review a set but it wasn't this
one:
<URL:https://lore.kernel.org/linux-media/20241129095142.87196-1-sakari.ailus@linux.intel.com/T/#t>.
:-)

> 
> I think this should come before 4/5.
> 
> On Tue, Dec 10, 2024 at 09:59:06AM +0200, Sakari Ailus wrote:
> > Obtain the link frequency from the sub-device instead of a control
> > handler. This allows obtaining it using the get_mbus_config() sub-device
> > pad op that which is only supported by the IVSC driver.
> 
> "which is the only method supported by the IVSC driver"
> 
> > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> > ---
> >  drivers/media/pci/intel/ipu6/ipu6-isys-csi2.c | 12 +++---------
> >  1 file changed, 3 insertions(+), 9 deletions(-)
> > 
> > diff --git a/drivers/media/pci/intel/ipu6/ipu6-isys-csi2.c b/drivers/media/pci/intel/ipu6/ipu6-isys-csi2.c
> > index 051898ce53f4..da8581a37e22 100644
> > --- a/drivers/media/pci/intel/ipu6/ipu6-isys-csi2.c
> > +++ b/drivers/media/pci/intel/ipu6/ipu6-isys-csi2.c
> > @@ -80,25 +80,19 @@ static const struct ipu6_csi2_error dphy_rx_errors[] = {
> >  s64 ipu6_isys_csi2_get_link_freq(struct ipu6_isys_csi2 *csi2)
> >  {
> >  	struct media_pad *src_pad;
> > -	struct v4l2_subdev *ext_sd;
> > -	struct device *dev;
> >  
> >  	if (!csi2)
> >  		return -EINVAL;
> >  
> > -	dev = &csi2->isys->adev->auxdev.dev;
> >  	src_pad = media_entity_remote_source_pad_unique(&csi2->asd.sd.entity);
> 
> Not a candidate for this patch, but can the source change, or can it be
> cached at probe time (or notifier bound time) ?

It could be, but why would you do that?

This would also prevent connecting multiple sensors to a single CSI-2
receiver.

> 
> >  	if (IS_ERR(src_pad)) {
> > -		dev_err(dev, "can't get source pad of %s (%ld)\n",
> > +		dev_err(&csi2->isys->adev->auxdev.dev,
> > +			"can't get source pad of %s (%ld)\n",
> >  			csi2->asd.sd.name, PTR_ERR(src_pad));
> >  		return PTR_ERR(src_pad);
> >  	}
> >  
> > -	ext_sd = media_entity_to_v4l2_subdev(src_pad->entity);
> > -	if (WARN(!ext_sd, "Failed to get subdev for %s\n", csi2->asd.sd.name))
> > -		return -ENODEV;
> > -
> > -	return v4l2_get_link_freq(ext_sd->ctrl_handler, 0, 0);
> > +	return v4l2_get_link_freq(src_pad, 0, 0);
> >  }
> >  
> >  static int csi2_subscribe_event(struct v4l2_subdev *sd, struct v4l2_fh *fh,
> 

-- 
Regards,

Sakari Ailus