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Re: [PATCH 1/2] mfd: arizona: Add GPIO maintain state flag

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On Fri, Apr 07, 2017 at 01:38:44PM +0100, Charles Keepax wrote:
> The Arizona devices only maintain the state of output GPIOs whilst the
> CODEC is active, this can cause issues if the CODEC suspends whilst
> something is relying on the state of one of its GPIOs. However, in
> many systems the CODEC GPIOs are used for audio related features
> and thus the state of the GPIOs is unimportant whilst the CODEC is
> suspended. Often keeping the CODEC resumed in such a system would
> incur a power impact that is unacceptable.
> 
> Add a flag through the second cell of the GPIO specifier in device
> tree, to allow the user to select whether a GPIO being configured as
> an output should keep the CODEC resumed.

If the whole codec can't be suspended, why does this need to be per 
GPIO? You could just have a single boolean property.

> 
> Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
> ---
>  Documentation/devicetree/bindings/mfd/arizona.txt | 5 ++++-
>  include/dt-bindings/mfd/arizona.h                 | 3 +++
>  2 files changed, 7 insertions(+), 1 deletion(-)

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Re: [PATCH 1/2] mfd: arizona: Add GPIO maintain state flag Rob Herring <robh@kernel.org> - 2017-04-10 22:20 +0200
  Re: [PATCH 1/2] mfd: arizona: Add GPIO maintain state flag Richard Fitzgerald <rf@opensource.wolfsonmicro.com> - 2017-04-11 11:40 +0200
    Re: [PATCH 1/2] mfd: arizona: Add GPIO maintain state flag Charles Keepax <ckeepax@opensource.wolfsonmicro.com> - 2017-04-13 11:20 +0200
      Re: [PATCH 1/2] mfd: arizona: Add GPIO maintain state flag Linus Walleij <linus.walleij@linaro.org> - 2017-04-13 14:20 +0200
        Re: [PATCH 1/2] mfd: arizona: Add GPIO maintain state flag Richard Fitzgerald <rf@opensource.wolfsonmicro.com> - 2017-04-13 14:30 +0200
          Re: [PATCH 1/2] mfd: arizona: Add GPIO maintain state flag Linus Walleij <linus.walleij@linaro.org> - 2017-04-13 14:50 +0200
            Re: [PATCH 1/2] mfd: arizona: Add GPIO maintain state flag Charles Keepax <ckeepax@opensource.wolfsonmicro.com> - 2017-04-13 15:10 +0200

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