Re: [PATCH v3] media: v4l2-flash: Enter LED off state after file handle closed

[ChiYuan Huang]

On Sat, Feb 21, 2026 at 04:48:48PM +0100, Jacek Anaszewski wrote:
Hi, Jacek:

> Hi ChiYuan,
> 
...
> On 1/12/26 10:20, cy_huang@xxxxxxxxxxx wrote:
> >   drivers/media/v4l2-core/v4l2-flash-led-class.c | 6 ++++++
> >   1 file changed, 6 insertions(+)
> > 
> > diff --git a/drivers/media/v4l2-core/v4l2-flash-led-class.c b/drivers/media/v4l2-core/v4l2-flash-led-class.c
> > index 355595a0fefa..46606f5cc192 100644
> > --- a/drivers/media/v4l2-core/v4l2-flash-led-class.c
> > +++ b/drivers/media/v4l2-core/v4l2-flash-led-class.c
> > @@ -623,6 +623,12 @@ static int v4l2_flash_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> >   		return 0;
> >   	if (led_cdev) {
> > +		/* If file handle is released, make sure LED enter off state */
> > +		ret = v4l2_ctrl_s_ctrl(v4l2_flash->ctrls[LED_MODE],
> > +				       V4L2_FLASH_LED_MODE_NONE);
> > +		if (ret)
> > +			return ret;
> > +
> >   		mutex_lock(&led_cdev->led_access);
> >   		if (v4l2_flash->ctrls[STROBE_SOURCE])
> > 
> > base-commit: 8ac28a6642d1cc8bac0632222e66add800b027fa
> 
> The patch itself looks good, but while at it I started wondering
> if we shouldn't move below STROBE_SOURCE access before the lock.
> I don't see now, why we placed it there.
> 
My assumption is LED should already be called 'led_sysfs_enable(false)',
no other APIs except V4L2 singular handle. But your guess is right. If we
put the change after the lock, should be more safe.

Thanks for the reviewing, if the common is to put after the lock, then
I can send v4 patch to fix it.
> Adding Sakari.
> 
> -- 
> Best regards,
> Jacek Anaszewski
>