Re: [PATCH v4 2/3] thermal: rockchip: support the sleep pinctrl state to avoid glitches in s2r

From: Doug Anderson
Date: Fri Oct 23 2015 - 11:25:55 EST


Caesar,

On Fri, Oct 23, 2015 at 4:25 AM, Caesar Wang <wxt@xxxxxxxxxxxxxx> wrote:
> When we come out of system suspend state (S3) the tsadc will have been
> reset and back at its default state. While reprogramming the tsadc
> it's possible that we'll glitch the output and unintentionally cause
> the "over temperature" GPIO to be asserted. Since the over
> temperature GPIO is often hooked up to something that will cause a
> reboot or shutdown in hardware, this glitch can be catastrophic on
> some boards.
>
> We'll add support for selecting the "sleep" pinctrl state at suspend
> time. Boards can use this to effectively disable the tsadc at suspend
> time and avoid glitches when the system is resumed.
>
> Signed-off-by: Caesar Wang <wxt@xxxxxxxxxxxxxx>
>
> ---
>
> Changes in v4:
> - take the Doug's commit as correct decription.
>
> Changes in v3:
> - Add the pinctrl state for in the suspend/resume.
>
> Changes in v2: None
> Changes in v1: None
>
> drivers/thermal/rockchip_thermal.c | 4 ++++
> 1 file changed, 4 insertions(+)

Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
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