Re: [PATCH v2 4/8] drm/i2c: tda998x: prepare for video input configuration

[Russell King - ARM Linux <linux@arm.linux.org.uk>]

On Wed, Aug 21, 2013 at 08:26:46PM +0200, Jean-Francois Moine wrote:
> On Wed Aug 14 12:43:29 PDT 2013, Sebastian Hesselbarth wrote:
> > From: Russell King <rmk+kernel at arm.linux.org.uk>
> > 
> > The video-input-port (VIP) is highly configurable. This prepares
> > current driver to allow to configure VIP configuration, as some
> > boards connect lcd controller and TDA998x "pin-swapped" and depend
> > on VIP to swap the pins by register configuration.
> > 
> > Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
> > Tested-by: Darren Etheridge <detheridge at ti.com>
> > Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth at gmail.com>
> 	[snip]
> 
> AFAIK, the TI boards have no "pin-swapped", nor has the Cubox (there is
> no need to set the bit CFG_GRA_SWAPRB of the register LCD_SPU_DMA_CTRL0
> of the Dove lcd for RGB or YUV formats).
> 
> Which board needs a special VIP configuration?

If you run the NXP driver, and then run this driver, things get messed
up - which has already been covered months ago when this patch was first
brought up.

It's there to ensure that the TDA998x is correctly configured no matter
what it's previous state is, and prevent the thing being fragile as hell.
No, reset doesn't restore its settings, only a power cycle does.