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Subject: Re: [PATCH v10 13/55] dt-bindings: input: atmel: add suspend mode
 support
To:     Jiada Wang <jiada_wang@mentor.com>, nick@shmanahar.org,
        dmitry.torokhov@gmail.com, jikos@kernel.org,
        benjamin.tissoires@redhat.com, bsz@semihalf.com
Cc:     linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
        erosca@de.adit-jv.com, Andrew_Gabbasov@mentor.com
References: <20200331105051.58896-1-jiada_wang@mentor.com>
 <20200331105051.58896-14-jiada_wang@mentor.com>
From:   Dmitry Osipenko <digetx@gmail.com>
Message-ID: <dd09ab5d-4e33-7ca0-9dfe-80be1cee307f@gmail.com>
Date:   Wed, 1 Apr 2020 18:42:33 +0300
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31.03.2020 13:50, Jiada Wang пишет:
> Add suspend mode support for atmel touchscreen driver
> 
> Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
> ---
>  .../bindings/input/atmel,maxtouch.txt         |  9 ++++++++
>  MAINTAINERS                                   |  1 +
>  include/dt-bindings/input/atmel_mxt_ts.h      | 23 +++++++++++++++++++
>  3 files changed, 33 insertions(+)
>  create mode 100644 include/dt-bindings/input/atmel_mxt_ts.h
> 
> diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
> index c88919480d37..0307e7f7bb43 100644
> --- a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
> +++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
> @@ -31,6 +31,15 @@ Optional properties for main touchpad device:
>  
>  - reset-gpios: GPIO specifier for the touchscreen's reset pin (active low)
>  
> +- atmel,suspend-mode: Select method used to suspend:
> +    MXT_SUSPEND_DEEP_SLEEP - use T7 to suspend the device into deep sleep
> +    MXT_SUSPEND_T9_CTRL - use T9.CTRL to turn off touch processing
> +    MXT_SUSPEND_REGULATOR - use regulators to power down device during suspend
> +    Definitions are in <dt-bindings/input/atmel_mxt_ts.h>.
> +
> +- vdd: Required supply regulator when MXT_SUSPEND_REGULATOR is used to suspend
> +- avdd: Required supply regulator when MXT_SUSPEND_REGULATOR is used to suspend

Some of NVIDIA Tegra devices have a VDD regulator in a form of GPIO,
which is turned off by default at a boot time, and thus, the
power-regulator needs to be enabled by the driver at a probe time in
order to power-up the touchscreen.

I think the VDD/AVDD description isn't correct because these are the
essential power regulators, they aren't used only for the suspending.

What about something more generic, like this:

- vdd: phandle to Power supply regulator
- avdd: phandle to Analog Power supply regulator