Re: [PATCH v2 7/9] media: subdev: Support privacy led in v4l2_subdev_enable/disable_streams()

[Tomi Valkeinen]

On 10/04/2024 13:11, Sakari Ailus wrote:
> Moi,
>
> On Fri, Apr 05, 2024 at 12:14:25PM +0300, Tomi Valkeinen wrote:
> > We support camera privacy leds with the .s_stream, in call_s_stream, but
> > we don't have that support when the subdevice implements
> > .enable/disable_streams.
> >
> > Add the support by enabling the led when the first stream for a
> > subdevice is enabled, and disabling the led then the last stream is
> > disabled.
> >
> > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
> > ---
> >   drivers/media/v4l2-core/v4l2-subdev.c | 12 ++++++++++++
> >   1 file changed, 12 insertions(+)
> >
> > diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
> > index b4981447961a..015f2fb423c9 100644
> > --- a/drivers/media/v4l2-core/v4l2-subdev.c
> > +++ b/drivers/media/v4l2-core/v4l2-subdev.c
> > @@ -2149,6 +2149,7 @@ int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad,
> >   {
> >   	struct device *dev = sd->entity.graph_obj.mdev->dev;
> >   	struct v4l2_subdev_state *state;
> > +	bool already_streaming;
> >   	u64 found_streams = 0;
> >   	unsigned int i;
> >   	int ret;
> > @@ -2197,6 +2198,11 @@ int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad,
> >   
> >   	dev_dbg(dev, "enable streams %u:%#llx\n", pad, streams_mask);
> >   
> > +	already_streaming = v4l2_subdev_is_streaming(sd);
> > +
> > +	if (!already_streaming)
> > +		v4l2_subdev_enable_privacy_led(sd);
> > +
> >   	/* Call the .enable_streams() operation. */
> >   	ret = v4l2_subdev_call(sd, pad, enable_streams, state, pad,
> >   			       streams_mask);
> > @@ -2216,6 +2222,9 @@ int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad,
> >   	}
> >   
> >   done:
> > +	if (ret && !already_streaming)
> > +		v4l2_subdev_disable_privacy_led(sd);
>
> I think you could also lit the LED only if enabling streaming succeeds.

This matches the implementation in s_stream. I'll change it to match the 
new one being discussed.

 Tomi