diff options
| author | Mika Westerberg | 2015-05-06 13:29:06 +0300 |
|---|---|---|
| committer | Linus Walleij | 2015-05-11 11:56:11 +0200 |
| commit | c884fbd452147e952ae160e750553d00ea4dc4c9 (patch) | |
| tree | 7e2488cb40d3b70ac525fd3ea9ca2b69eda0c3f2 | |
| parent | 442b2494b17d1a4f0a14721580271eb23ebffd42 (diff) | |
gpio / ACPI: Add support for retrieving GpioInt resources from a device
ACPI specification knows two types of GPIOs: GpioIo and GpioInt. The latter
is used to describe that a given device interrupt line is connected to a
specific GPIO pin. Typical ACPI _CRS entry for such device looks like
below:
Name (_CRS, ResourceTemplate ()
{
I2cSerialBus (0x004A, ControllerInitiated, 0x00061A80,
AddressingMode7Bit, "\\_SB.PCI0.I2C6",
0x00, ResourceConsumer)
GpioIo (Exclusive, PullDefault, 0x0000, 0x0000,
IoRestrictionOutputOnly, "\\_SB.GPO0",
0x00, ResourceConsumer)
{
0x004B
}
GpioInt (Level, ActiveLow, Shared, PullDefault, 0x0000,
"\\_SB.GPO0", 0x00, ResourceConsumer)
{
0x004C
}
})
Currently drivers need to request a GPIO corresponding to the right GpioInt
and then translate that to Linux IRQ number. This adds unnecessary lines of
boiler-plate code.
We can ease this a bit by introducing acpi_dev_gpio_irq_get() analogous to
of_irq_get(). This function translates given GpioInt resource under the
device in question to the suitable Linux IRQ number.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
| -rw-r--r-- | drivers/gpio/gpiolib-acpi.c | 29 | ||||
| -rw-r--r-- | include/linux/acpi.h | 7 |
2 files changed, 36 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index d2303d50f561..bff29bb0a3fe 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -514,6 +514,35 @@ struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, return lookup.desc ? lookup.desc : ERR_PTR(-ENOENT); } +/** + * acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number + * @adev: pointer to a ACPI device to get IRQ from + * @index: index of GpioInt resource (starting from %0) + * + * If the device has one or more GpioInt resources, this function can be + * used to translate from the GPIO offset in the resource to the Linux IRQ + * number. + * + * Return: Linux IRQ number (>%0) on success, negative errno on failure. + */ +int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index) +{ + int idx, i; + + for (i = 0, idx = 0; idx <= index; i++) { + struct acpi_gpio_info info; + struct gpio_desc *desc; + + desc = acpi_get_gpiod_by_index(adev, NULL, i, &info); + if (IS_ERR(desc)) + break; + if (info.gpioint && idx++ == index) + return gpiod_to_irq(desc); + } + return -ENOENT; +} +EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get); + static acpi_status acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address, u32 bits, u64 *value, void *handler_context, diff --git a/include/linux/acpi.h b/include/linux/acpi.h index e4da5e35e29c..f57c440642cd 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -721,6 +721,8 @@ static inline void acpi_dev_remove_driver_gpios(struct acpi_device *adev) if (adev) adev->driver_gpios = NULL; } + +int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index); #else static inline int acpi_dev_add_driver_gpios(struct acpi_device *adev, const struct acpi_gpio_mapping *gpios) @@ -728,6 +730,11 @@ static inline int acpi_dev_add_driver_gpios(struct acpi_device *adev, return -ENXIO; } static inline void acpi_dev_remove_driver_gpios(struct acpi_device *adev) {} + +static inline int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index) +{ + return -ENXIO; +} #endif /* Device properties */ |