Re: [GIT PULL FOR v3.10] Camera sensors patches

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Mauro,

On Sunday 14 April 2013 16:59:58 Mauro Carvalho Chehab wrote:
> Em Fri, 12 Apr 2013 11:13:06 +0200 Laurent Pinchart escreveu:
> > Hi Mauro,
> > 
> > The following changes since commit 
81e096c8ac6a064854c2157e0bf802dc4906678c:
> >   [media] budget: Add support for Philips Semi Sylt PCI ref. design
> > 
> > (2013-04-08 07:28:01 -0300)
> > 
> > are available in the git repository at:
> >   git://linuxtv.org/pinchartl/media.git sensors/next
> > 
> > for you to fetch changes up to c890926a06339944790c5c265e21e8547aa55e49:
> >   mt9p031: Use the common clock framework (2013-04-12 11:07:07 +0200)
> > 
> > ----------------------------------------------------------------
> > 
> > Laurent Pinchart (5):
> >       mt9m032: Fix PLL setup
> >       mt9m032: Define MT9M032_READ_MODE1 bits
> >       mt9p031: Use devm_* managed helpers
> >       mt9p031: Add support for regulators
> >       mt9p031: Use the common clock framework
> 
> Hmm... It seems ugly to have regulators and clock framework and other SoC
> calls inside an i2c driver that can be used by a device that doesn't have
> regulators.
> 
> I'm not sure what's the best solution for it, so, I'll be adding those two
> patches, but it seems that we'll need to restrict the usage of those calls
> only if the caller driver is a platform driver.

The MT9P031 needs power supplies and a clock on all platforms, regardless of 
the bridge bus type. I suppose the use case that mostly concerns you here is 
USB webcams where the power supplies and the clock are controlled 
automatically by the device. If we ever need to support such a device in the 
future we can of course revisit the driver then, and one possible solution 
would be to register fixed voltage regulators and a fixed clock.

-- 
Regards,

Laurent Pinchart