Re: [PATCH 1/6] media: ov5693: Add support for a privacy-led GPIO

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

Hi Hans,

On Wed, Nov 30, 2022 at 12:11:44AM +0100, Hans de Goede wrote:
> Add support for a privacy-led GPIO.
> 
> Making the privacy LED to controlable from userspace, as using the LED
> class subsystem would do, would make it too easy for spy-ware to disable
> the LED.
> 
> To avoid this have the sensor driver directly control the LED.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> Note an additional advantage of directly controlling the GPIO is that
> GPIOs are tied directly to consumer devices. Where as with a LED class
> device, there would need to be some mechanism to tie the right LED
> (e.g front or back) to the right sensor.

Thanks for the patch.

This approach has the drawback that support needs to be added for each
sensor separately. Any idea how many sensor drivers might need this?

Most implementations have privacy LED hard-wired to the sensor's power
rails so it'll be lit whenever the sensor is powered on.

If there would be more than just a couple of these I'd instead create a LED
class device and hook it up to the sensor in V4L2.

-- 
Kind regards,

Sakari Ailus