Re: [PATCH v3 3/7] drm: Add driver for Solomon SSD130X OLED displays

[Javier Martinez Canillas]

On 2/9/22 16:03, Mark Brown wrote:
> On Wed, Feb 09, 2022 at 03:50:13PM +0100, Javier Martinez Canillas wrote:

[snip]

> 
>> But I understand why the Device Tree binding and fbdev driver used VBAT
>> since that's what the documentation mentions.
> 
> What is "the documentation" in this context and how is that distinct
> from the datasheet for the display controller?  In general the consumer
> driver should be using the name from the datasheet and the regulator
> itself should get a regulator-name reflecting the name in the schematic.
>

For "documentation" I meant the datasheet that mentions VBAT but I got
what you mean and will also propose a change to the binding to rename
the property to vcc-supply instead to match the pin name in the device.

>>> It is depressingly common to see broken code here, unfortunately
>>> graphics drivers seem like one of the most common offendors.
> 
>> I'll include a patch for the existing DT binding and mark the vbat-supply
>> property as required. Probably we won't be able to change the fbdev driver
>> without causing regressions, and I'm not interested in that driver anyways.
> 
> There should be little danger of causing regressions given that a dummy
> regualtor will be provided when one is missing.

Right, I forgot that a dummy regulator is provided in that case. Perfect.

Best regards,
-- 
Javier Martinez Canillas
Linux Engineering
Red Hat