Re: [PATCH v2 4/5] fbdev/ssd1307fb: add support to enable VBAT

[Rob Herring <robh@kernel.org>]

On Thu, Jan 19, 2017 at 7:15 AM, Tomi Valkeinen <tomi.valkeinen@ti.com> wrote:
> On 19/01/17 00:33, Rob Herring wrote:
>> On Fri, Jan 13, 2017 at 12:35:48PM +0200, Jyri Sarha wrote:
>>> From: Tomi Valkeinen <tomi.valkeinen@ti.com>
>>>
>>> SSD1306 needs VBAT when it is wired in charge pump configuration. This
>>> patch adds support to the driver to enable VBAT regulator at init time.
>>>
>>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
>>> Reviewed-by: Roger Quadros <rogerq@ti.com>
>>> Signed-off-by: Jyri Sarha <jsarha@ti.com>
>>> ---
>>>  .../devicetree/bindings/display/ssd1307fb.txt        |  1 +
>>>  drivers/video/fbdev/ssd1307fb.c                      | 20 +++++++++++++++++++-
>>>  2 files changed, 20 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/display/ssd1307fb.txt b/Documentation/devicetree/bindings/display/ssd1307fb.txt
>>> index 6617df6..209d931 100644
>>> --- a/Documentation/devicetree/bindings/display/ssd1307fb.txt
>>> +++ b/Documentation/devicetree/bindings/display/ssd1307fb.txt
>>> @@ -16,6 +16,7 @@ Required properties:
>>>  Optional properties:
>>>    - reset-gpios: The GPIO used to reset the OLED display, if available. See
>>>                   Documentation/devicetree/bindings/gpio/gpio.txt for details.
>>> +  - vbat-supply: The supply for VBAT
>>
>> According to the datasheet, SSD1307 has 2 supplies: Vdd and Vcc
>>
>> I don't see any mention of a charge pump, so that must be an external
>> component.
>
> VBAT is for SSD1306. Perhaps the DT doc should mention it.

Datasheet says VBAT is reserved, connect to Vdd. I would just describe
Vdd and Vcc in that case.

Rob