Re: [PATCH v2] backlight: lp855x: Add enable regulator

From: Rob Herring
Date: Tue Jun 14 2016 - 16:09:43 EST


On Fri, Jun 10, 2016 at 12:39:57PM -0700, Brian Norris wrote:
> The LP8556 datasheet describes an EN/VDDIO input, which serves "both as
> a chip enable and as a power supply reference for PWM, SDA, and SCL
> inputs." The LP8556 that I'm testing doesn't respond properly if I try
> to talk I2C to it too quickly after enabling VDDIO, and the LP8555
> datasheet mentions a t_RESPONSE delay of up to 1 millisecond.
>
> Support this EN/VDDIO by adding a regulator property to the binding;
> enabling this regulator at probe time; and sleeping for 1 to 2ms, if the
> EN/VDDIO regulator was provided.
>
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
> ---
> v2: s/TS8555/LP8555/ in comment (typo)
>
> .../devicetree/bindings/leds/backlight/lp855x.txt | 2 ++

I would have picked 'vddio' as the name, but it's fine.

Acked-by: Rob Herring <robh@xxxxxxxxxx>

> drivers/video/backlight/lp855x_bl.c | 29 ++++++++++++++++++++++
> 2 files changed, 31 insertions(+)