gpiolib: acpi: Set pin value, based on bias, more accurately

ACPI GpioIo() resource may have different bias settings.
For now, we distinguish only PullUp() setting in order to configure
the initial state of a pin.

Take into consideration the rest of the possible choices as well,
i.e. PullDown, PullNone and PullDefault, when configuring the initial state
of the pin.

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

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 36cd9abe5e555d75eb19c2d647692d69b05d62fe..878c7a7dea8b2dc841327de02ea0c232a01afeda 100644 (file)
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -444,8 +444,6 @@ static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
 static enum gpiod_flags
 acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
 {
-       bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
-
        switch (agpio->io_restriction) {
        case ACPI_IO_RESTRICT_INPUT:
                return GPIOD_IN;
@@ -454,16 +452,26 @@ acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
                 * ACPI GPIO resources don't contain an initial value for the
                 * GPIO. Therefore we deduce that value from the pull field
                 * instead. If the pin is pulled up we assume default to be
-                * high, otherwise low.
+                * high, if it is pulled down we assume default to be low,
+                * otherwise we leave pin untouched.
                 */
-               return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+               switch (agpio->pin_config) {
+               case ACPI_PIN_CONFIG_PULLUP:
+                       return GPIOD_OUT_HIGH;
+               case ACPI_PIN_CONFIG_PULLDOWN:
+                       return GPIOD_OUT_LOW;
+               default:
+                       break;
+               }
        default:
-               /*
-                * Assume that the BIOS has configured the direction and pull
-                * accordingly.
-                */
-               return GPIOD_ASIS;
+               break;
        }
+
+       /*
+        * Assume that the BIOS has configured the direction and pull
+        * accordingly.
+        */
+       return GPIOD_ASIS;
 }
 
 static int