gpiolib: acpi: Set initial value for output pin based on bias and polarity

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GpioIo() resources don't contain an initial value for the output pin.
Therefore instead of deducting its value solely based on bias field
we should deduce that value from the polarity and the bias fields.
Typical scenario is, when pin is defined in the table and its polarity,
specified in _DSD or via platform code, is defined as active low,
in the following call chain:

  -> acpi_populate_gpio_lookup()
     -> acpi_gpio_to_gpiod_flags()

it will return GPIOD_OUT_HIGH if bias is set no matter if polarity
is GPIO_ACTIVE_LOW, so it will return the current level instead of
the logical level.

Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Vasile-Laurentiu Stanimir <vasile-laurentiu.stanimir@windriver.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

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Vasile-Laurentiu Stanimir 2020-10-01 20:12:12 +03:00 • committed by Andy Shevchenko

parent 1a81f19154

commit 56f7058af0

1 changed files with 12 additions and 9 deletions

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drivers/gpio/gpiolib-acpi.c

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