Re: [PATCH 4/4] ARM: tegra: roth: add display DT node

[Alexandre Courbot <acourbot@nvidia.com>]

On 07/03/2014 12:55 AM, Stephen Warren wrote:
> On 07/02/2014 06:19 AM, Alexandre Courbot wrote:
>> DSI support has been fixed to support continuous clock behavior that the
>> panel used on SHIELD requires, so finally add its device tree node since
>> it is functional.
>
>> diff --git a/arch/arm/boot/dts/tegra114-roth.dts b/arch/arm/boot/dts/tegra114-roth.dts
>
>> +	host1x@50000000 {
>> +		dsi@54300000 {
>
> That node looks fine, but I wonder why we need to mark a bunch of
> regulators as always-on? shouldn't the references to vdd-supply and
> power-supply from this node be enough? If not, perhaps the tree
> structure of the regulators isn't correct, or the DSI or panel bindings
> don't allow enough regulators to be referenced?

regulator-always-on is indeed not needed for vdd_lcd. I actually had a 
patch in my tree removing this line that I forgot to squash. Will post a 
v2 for this patch that fixes this, thanks.

vdd-2v8-display needs to remain always-on however. Here we may hit a 
limitation of the simple-panel driver, where only one power supply can 
be provided.