[Meego-kernel] [PATCH] MRST Tablet camera driver ver-0.95 (re-send), fix 8112

[Arjan van de Ven]

On 6/12/2011 9:52 PM, He, Yong M wrote:
> Hi Arjan ,
>
> about the power state of camera subdevs,
> the original idea is to power off all subdevs (camera sensors) when there's no user application was opening this device.
> (the libCI breaks down all its operations to many very small ones, each one will do an open and close on the /dev/video0 file. so there're many power off&on for even a single snapshot operation)
> but since we updated the firmware for AF feature, each power on, we need to re-load the firmware, it will break the focus status,,,
> so I remove this power-off. and only do power off when the driver's suspend method is called (for example, system goes to S0i3), not every time when it is closed.
>
there is no suspend!

now if you have very frequent in/outs and you need to "debounce" them, 
the runtime PM framework supports that where you can set up code to 
delay this by, say, 100 msec.
I would suggest looking into that angle.