ACPI: x86: Introduce an acpi_quirk_skip_gpio_event_handlers() helper

x86 ACPI boards which ship with only Android as their factory image usually
have pretty broken ACPI tables, relying on everything being hardcoded in
the factory kernel image and often disabling parts of the ACPI enumeration
kernel code to avoid the broken tables causing issues.

Part of this broken ACPI code is that sometimes these boards have _AEI
ACPI GPIO event handlers which are broken.

So far this has been dealt with in the platform/x86/x86-android-tablets.c
module, which contains various workarounds for these devices, by it calling
acpi_gpiochip_free_interrupts() on gpiochip-s with troublesome handlers to
disable the handlers.

But in some cases this is too late, if the handlers are of the edge type
then gpiolib-acpi.c's code will already have run them at boot.
This can cause issues such as GPIOs ending up as owned by "ACPI:OpRegion",
making them unavailable for drivers which actually need them.

Boards with these broken ACPI tables are already listed in
drivers/acpi/x86/utils.c for e.g. acpi_quirk_skip_i2c_client_enumeration().
Extend the quirks mechanism for a new acpi_quirk_skip_gpio_event_handlers()
helper, this re-uses the DMI-ids rather then having to duplicate the same
DMI table in gpiolib-acpi.c .

Also add the new ACPI_QUIRK_SKIP_GPIO_EVENT_HANDLERS quirk to existing
boards with troublesome ACPI gpio event handlers, so that the current
acpi_gpiochip_free_interrupts() hack can be removed from
x86-android-tablets.c .

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>

2 files changed, 24 insertions, 3 deletions

diff --git a/drivers/acpi/x86/utils.c b/drivers/acpi/x86/utils.c
index e45285d4e62a..4bf57cce30bb 100644
--- a/drivers/acpi/x86/utils.c
+++ b/drivers/acpi/x86/utils.c
@@ -251,6 +251,7 @@ bool force_storage_d3(void)
 #define ACPI_QUIRK_UART1_TTY_UART2_SKIP				BIT(1)
 #define ACPI_QUIRK_SKIP_ACPI_AC_AND_BATTERY			BIT(2)
 #define ACPI_QUIRK_USE_ACPI_AC_AND_BATTERY			BIT(3)
+#define ACPI_QUIRK_SKIP_GPIO_EVENT_HANDLERS			BIT(4)
 
 static const struct dmi_system_id acpi_quirk_skip_dmi_ids[] = {
 	/*
@@ -286,7 +287,8 @@ static const struct dmi_system_id acpi_quirk_skip_dmi_ids[] = {
 		},
 		.driver_data = (void *)(ACPI_QUIRK_SKIP_I2C_CLIENTS |
 					ACPI_QUIRK_UART1_TTY_UART2_SKIP |
-					ACPI_QUIRK_SKIP_ACPI_AC_AND_BATTERY),
+					ACPI_QUIRK_SKIP_ACPI_AC_AND_BATTERY |
+					ACPI_QUIRK_SKIP_GPIO_EVENT_HANDLERS),
 	},
 	{
 		.matches = {
@@ -294,7 +296,8 @@ static const struct dmi_system_id acpi_quirk_skip_dmi_ids[] = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "TF103C"),
 		},
 		.driver_data = (void *)(ACPI_QUIRK_SKIP_I2C_CLIENTS |
-					ACPI_QUIRK_SKIP_ACPI_AC_AND_BATTERY),
+					ACPI_QUIRK_SKIP_ACPI_AC_AND_BATTERY |
+					ACPI_QUIRK_SKIP_GPIO_EVENT_HANDLERS),
 	},
 	{
 		/* Lenovo Yoga Tablet 2 1050F/L */
@@ -336,7 +339,8 @@ static const struct dmi_system_id acpi_quirk_skip_dmi_ids[] = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "M890BAP"),
 		},
 		.driver_data = (void *)(ACPI_QUIRK_SKIP_I2C_CLIENTS |
-					ACPI_QUIRK_SKIP_ACPI_AC_AND_BATTERY),
+					ACPI_QUIRK_SKIP_ACPI_AC_AND_BATTERY |
+					ACPI_QUIRK_SKIP_GPIO_EVENT_HANDLERS),
 	},
 	{
 		/* Whitelabel (sold as various brands) TM800A550L */
@@ -413,6 +417,20 @@ int acpi_quirk_skip_serdev_enumeration(struct device *controller_parent, bool *s
 	return 0;
 }
 EXPORT_SYMBOL_GPL(acpi_quirk_skip_serdev_enumeration);
+
+bool acpi_quirk_skip_gpio_event_handlers(void)
+{
+	const struct dmi_system_id *dmi_id;
+	long quirks;
+
+	dmi_id = dmi_first_match(acpi_quirk_skip_dmi_ids);
+	if (!dmi_id)
+		return false;
+
+	quirks = (unsigned long)dmi_id->driver_data;
+	return (quirks & ACPI_QUIRK_SKIP_GPIO_EVENT_HANDLERS);
+}
+EXPORT_SYMBOL_GPL(acpi_quirk_skip_gpio_event_handlers);
 #endif
 
 /* Lists of PMIC ACPI HIDs with an (often better) native charger driver */
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index d8a421ce26a8..31ae0adbb295 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -536,6 +536,9 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
 	if (ACPI_FAILURE(status))
 		return;
 
+	if (acpi_quirk_skip_gpio_event_handlers())
+		return;
+
 	acpi_walk_resources(handle, METHOD_NAME__AEI,
 			    acpi_gpiochip_alloc_event, acpi_gpio);