[Meego-kernel] [PATCH] MRST Tablet camera driver ver-0.95 (re-send), fix 8112
Arjan van de Ven
arjan at linux.intel.com
Mon Jun 13 06:40:50 PDT 2011
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.
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