N900 board code in 3.14

Sebastian Reichel sre at ring0.de
Sat Nov 16 10:50:33 EST 2013


On Sat, Nov 16, 2013 at 06:12:26AM -0800, Tony Lindgren wrote:
> [...]
> >  b) I could not get the 32GB eMMC working. For me the chip is not found
> >     and I don't know how to debug it.
> 
> OK the eMMC issue might be related to the control module PBIAS
> register support missing. If so, that should be fixable with the
> auxdata until we have a minimal control module device driver to
> deal with the PBIAS and expose those features as regulators to
> the omap-hsmmc driver.

I wasn't aware, that PBIAS register support is missing for DT
boot. The existing board code uses a 2.8-3.0V regulator for mmc1,
so missing PBIAS is probably the problem.

> > [...]
> > 
> > My suggestion would be:
> >  1. Find a better workaround for omapdss to acquire the SDI
> >     regulator. My current hack is obviously not acceptable.
> >  2. Load the panel driver via DT as seen above and reference
> >     the omapdss interface with something like the above
> >     "ti,dss-source".
> 
> To me it seems that we should be able to add minimal panel entries to DT
> if we stick to existing standard bindings. Then the timings etc can be
> set up based on the compatible flag. So I would leave out the properties
> for ti,sdi-datapairs and ti,dss-source for now, and just set those in
> the driver based on the sony,acx565akm compatible flag. Or maybe it should
> be sony,acx565akm-n900 if there's some board specific configuration info.

So we add reset-gpio and label to the DT data (they are panel
specific and independent of omapdss) and just hardcode "dsi.0"
with 2 data lanes into the driver? That sounds fine for me.

If neither Tomi nor anybody else has better ideas I will cook a
patch for that. I'm not sure how to setup the vdds_sdi regulator for
omapdss, though. Is there an example for a legacy driver using a DT
regulator available?

> [...]

-- Sebastian
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