gpiolib: acpi: Introduce NO_RESTRICTION quirk

Allow to relax IoRestriction for certain cases.

One of the use case is incorrectly cooked ACPI table where interrupt pin is
defined with GpioIo() macro with IoRestrictionOutputOnly.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib-acpi.c

@@ -496,11 +496,18 @@ int
 acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, struct acpi_gpio_info *info)
 {
 	struct device *dev = &info->adev->dev;
+	enum gpiod_flags old = *flags;
 	int ret;
 
-	ret = __acpi_gpio_update_gpiod_flags(flags, info->flags);
-	if (ret)
-		dev_dbg(dev, "Override GPIO initialization flags\n");
+	ret = __acpi_gpio_update_gpiod_flags(&old, info->flags);
+	if (info->quirks & ACPI_GPIO_QUIRK_NO_IO_RESTRICTION) {
+		if (ret)
+			dev_warn(dev, FW_BUG "GPIO not in correct mode, fixing\n");
+	} else {
+		if (ret)
+			dev_dbg(dev, "Override GPIO initialization flags\n");
+		*flags = old;
+	}
 
 	return ret;
 }

include/linux/acpi.h

@@ -978,6 +978,10 @@ struct acpi_gpio_mapping {
 	const char *name;
 	const struct acpi_gpio_params *data;
 	unsigned int size;
+
+/* Ignore IoRestriction field */
+#define ACPI_GPIO_QUIRK_NO_IO_RESTRICTION	BIT(0)
+
 	unsigned int quirks;
 };