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authorLinus Torvalds <torvalds@linux-foundation.org>2013-05-06 22:40:55 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2013-05-06 22:40:55 (GMT)
commit30c67e93c526639aaac90fa873800104b7c16d16 (patch)
tree6d8d0fd248d4e60bdc175dacbd196fc44f23ce11 /drivers/gpio/gpiolib-acpi.c
parentf87bb9ee62700fa11713c630ac5671f253233b94 (diff)
parent08ffb2229fafc2c3a696b325a74bf4198d6b91d7 (diff)
downloadlinux-fsl-qoriq-30c67e93c526639aaac90fa873800104b7c16d16.tar.xz
Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux
Pull GPIO changes from Grant Likely: "The usual selection of bug fixes and driver updates for GPIO. Nothing really stands out except the addition of the GRGPIO driver and some enhacements to ACPI support" I'm pulling this despite the earlier mess. Let's hope it compiles these days. * tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux: (46 commits) gpio: grgpio: Add irq support gpio: grgpio: Add device driver for GRGPIO cores gpiolib-acpi: introduce acpi_get_gpio_by_index() helper GPIO: gpio-generic: remove kfree() from bgpio_remove call gpio / ACPI: Handle ACPI events in accordance with the spec gpio: lpc32xx: Fix off-by-one valid range checking for bank gpio: mcp23s08: convert driver to DT gpio/omap: force restore if context loss is not detectable gpio/omap: optimise interrupt service routine gpio/omap: remove extra context restores in *_runtime_resume() gpio/omap: free irq domain in probe() failure paths gpio: gpio-generic: Add 16 and 32 bit big endian byte order support gpio: samsung: Add terminating entry for exynos_pinctrl_ids gpio: mvebu: add dbg_show function MAX7301 GPIO: Do not force SPI speed when using OF Platform gpio: gpio-tps65910.c: fix checkpatch error gpio: gpio-timberdale.c: fix checkpatch error gpio: gpio-tc3589x.c: fix checkpatch errors gpio: gpio-stp-xway.c: fix checkpatch error gpio: gpio-sch.c: fix checkpatch error ...
Diffstat (limited to 'drivers/gpio/gpiolib-acpi.c')
-rw-r--r--drivers/gpio/gpiolib-acpi.c217
1 files changed, 197 insertions, 20 deletions
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index a063eb0..5c1ef2b 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 +200,119 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
}
}
EXPORT_SYMBOL(acpi_gpiochip_request_interrupts);
+
+struct acpi_gpio_lookup {
+ struct acpi_gpio_info info;
+ int index;
+ int gpio;
+ int n;
+};
+
+static int acpi_find_gpio(struct acpi_resource *ares, void *data)
+{
+ struct acpi_gpio_lookup *lookup = data;
+
+ if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
+ return 1;
+
+ if (lookup->n++ == lookup->index && lookup->gpio < 0) {
+ const struct acpi_resource_gpio *agpio = &ares->data.gpio;
+
+ lookup->gpio = acpi_get_gpio(agpio->resource_source.string_ptr,
+ agpio->pin_table[0]);
+ lookup->info.gpioint =
+ agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
+ }
+
+ return 1;
+}
+
+/**
+ * acpi_get_gpio_by_index() - get a GPIO number from device resources
+ * @dev: pointer to a device to get GPIO from
+ * @index: index of GpioIo/GpioInt resource (starting from %0)
+ * @info: info pointer to fill in (optional)
+ *
+ * Function goes through ACPI resources for @dev and based on @index looks
+ * up a GpioIo/GpioInt resource, translates it to the Linux GPIO number,
+ * and returns it. @index matches GpioIo/GpioInt resources only so if there
+ * are total %3 GPIO resources, the index goes from %0 to %2.
+ *
+ * If the GPIO cannot be translated or there is an error, negative errno is
+ * returned.
+ *
+ * Note: if the GPIO resource has multiple entries in the pin list, this
+ * function only returns the first.
+ */
+int acpi_get_gpio_by_index(struct device *dev, int index,
+ struct acpi_gpio_info *info)
+{
+ struct acpi_gpio_lookup lookup;
+ struct list_head resource_list;
+ struct acpi_device *adev;
+ acpi_handle handle;
+ int ret;
+
+ if (!dev)
+ return -EINVAL;
+
+ handle = ACPI_HANDLE(dev);
+ if (!handle || acpi_bus_get_device(handle, &adev))
+ return -ENODEV;
+
+ memset(&lookup, 0, sizeof(lookup));
+ lookup.index = index;
+ lookup.gpio = -ENODEV;
+
+ INIT_LIST_HEAD(&resource_list);
+ ret = acpi_dev_get_resources(adev, &resource_list, acpi_find_gpio,
+ &lookup);
+ if (ret < 0)
+ return ret;
+
+ acpi_dev_free_resource_list(&resource_list);
+
+ if (lookup.gpio >= 0 && info)
+ *info = lookup.info;
+
+ return lookup.gpio;
+}
+EXPORT_SYMBOL_GPL(acpi_get_gpio_by_index);
+
+/**
+ * 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);