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-rw-r--r--drivers/gpio/gpiolib-acpi.c140
1 files changed, 120 insertions, 20 deletions
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index a063eb04b6ce..89336c4f82cd 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -17,6 +17,13 @@
#include <linux/acpi.h>
#include <linux/interrupt.h>
+struct acpi_gpio_evt_pin {
+ struct list_head node;
+ acpi_handle *evt_handle;
+ unsigned int pin;
+ unsigned int irq;
+};
+
static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
{
if (!gc->dev)
@@ -54,7 +61,6 @@ int acpi_get_gpio(char *path, int pin)
}
EXPORT_SYMBOL_GPL(acpi_get_gpio);
-
static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
{
acpi_handle handle = data;
@@ -64,6 +70,27 @@ static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
return IRQ_HANDLED;
}
+static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
+{
+ struct acpi_gpio_evt_pin *evt_pin = data;
+ struct acpi_object_list args;
+ union acpi_object arg;
+
+ arg.type = ACPI_TYPE_INTEGER;
+ arg.integer.value = evt_pin->pin;
+ args.count = 1;
+ args.pointer = &arg;
+
+ acpi_evaluate_object(evt_pin->evt_handle, NULL, &args, NULL);
+
+ return IRQ_HANDLED;
+}
+
+static void acpi_gpio_evt_dh(acpi_handle handle, void *data)
+{
+ /* The address of this function is used as a key. */
+}
+
/**
* acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
* @chip: gpio chip
@@ -73,15 +100,13 @@ static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
* chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
* gpio pins have acpi event methods and assigns interrupt handlers that calls
* the acpi event methods for those pins.
- *
- * Interrupts are automatically freed on driver detach
*/
-
void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
{
struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
struct acpi_resource *res;
- acpi_handle handle, ev_handle;
+ acpi_handle handle, evt_handle;
+ struct list_head *evt_pins = NULL;
acpi_status status;
unsigned int pin;
int irq, ret;
@@ -98,13 +123,30 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
if (ACPI_FAILURE(status))
return;
- /* If a gpio interrupt has an acpi event handler method, then
- * set up an interrupt handler that calls the acpi event handler
- */
+ status = acpi_get_handle(handle, "_EVT", &evt_handle);
+ if (ACPI_SUCCESS(status)) {
+ evt_pins = kzalloc(sizeof(*evt_pins), GFP_KERNEL);
+ if (evt_pins) {
+ INIT_LIST_HEAD(evt_pins);
+ status = acpi_attach_data(handle, acpi_gpio_evt_dh,
+ evt_pins);
+ if (ACPI_FAILURE(status)) {
+ kfree(evt_pins);
+ evt_pins = NULL;
+ }
+ }
+ }
+ /*
+ * If a GPIO interrupt has an ACPI event handler method, or _EVT is
+ * present, set up an interrupt handler that calls the ACPI event
+ * handler.
+ */
for (res = buf.pointer;
res && (res->type != ACPI_RESOURCE_TYPE_END_TAG);
res = ACPI_NEXT_RESOURCE(res)) {
+ irq_handler_t handler = NULL;
+ void *data;
if (res->type != ACPI_RESOURCE_TYPE_GPIO ||
res->data.gpio.connection_type !=
@@ -115,23 +157,42 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
if (pin > chip->ngpio)
continue;
- sprintf(ev_name, "_%c%02X",
- res->data.gpio.triggering ? 'E' : 'L', pin);
-
- status = acpi_get_handle(handle, ev_name, &ev_handle);
- if (ACPI_FAILURE(status))
- continue;
-
irq = chip->to_irq(chip, pin);
if (irq < 0)
continue;
+ if (pin <= 255) {
+ acpi_handle ev_handle;
+
+ sprintf(ev_name, "_%c%02X",
+ res->data.gpio.triggering ? 'E' : 'L', pin);
+ status = acpi_get_handle(handle, ev_name, &ev_handle);
+ if (ACPI_SUCCESS(status)) {
+ handler = acpi_gpio_irq_handler;
+ data = ev_handle;
+ }
+ }
+ if (!handler && evt_pins) {
+ struct acpi_gpio_evt_pin *evt_pin;
+
+ evt_pin = kzalloc(sizeof(*evt_pin), GFP_KERNEL);
+ if (!evt_pin)
+ continue;
+
+ list_add_tail(&evt_pin->node, evt_pins);
+ evt_pin->evt_handle = evt_handle;
+ evt_pin->pin = pin;
+ evt_pin->irq = irq;
+ handler = acpi_gpio_irq_handler_evt;
+ data = evt_pin;
+ }
+ if (!handler)
+ continue;
+
/* Assume BIOS sets the triggering, so no flags */
- ret = devm_request_threaded_irq(chip->dev, irq, NULL,
- acpi_gpio_irq_handler,
- 0,
- "GPIO-signaled-ACPI-event",
- ev_handle);
+ ret = devm_request_threaded_irq(chip->dev, irq, NULL, handler,
+ 0, "GPIO-signaled-ACPI-event",
+ data);
if (ret)
dev_err(chip->dev,
"Failed to request IRQ %d ACPI event handler\n",
@@ -139,3 +200,42 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
}
}
EXPORT_SYMBOL(acpi_gpiochip_request_interrupts);
+
+
+/**
+ * acpi_gpiochip_free_interrupts() - Free GPIO _EVT ACPI event interrupts.
+ * @chip: gpio chip
+ *
+ * Free interrupts associated with the _EVT method for the given GPIO chip.
+ *
+ * The remaining ACPI event interrupts associated with the chip are freed
+ * automatically.
+ */
+void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
+{
+ acpi_handle handle;
+ acpi_status status;
+ struct list_head *evt_pins;
+ struct acpi_gpio_evt_pin *evt_pin, *ep;
+
+ if (!chip->dev || !chip->to_irq)
+ return;
+
+ handle = ACPI_HANDLE(chip->dev);
+ if (!handle)
+ return;
+
+ status = acpi_get_data(handle, acpi_gpio_evt_dh, (void **)&evt_pins);
+ if (ACPI_FAILURE(status))
+ return;
+
+ list_for_each_entry_safe_reverse(evt_pin, ep, evt_pins, node) {
+ devm_free_irq(chip->dev, evt_pin->irq, evt_pin);
+ list_del(&evt_pin->node);
+ kfree(evt_pin);
+ }
+
+ acpi_detach_data(handle, acpi_gpio_evt_dh);
+ kfree(evt_pins);
+}
+EXPORT_SYMBOL(acpi_gpiochip_free_interrupts);