From c884fbd452147e952ae160e750553d00ea4dc4c9 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Wed, 6 May 2015 13:29:06 +0300 Subject: [PATCH] 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 Acked-by: Rafael J. Wysocki Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib-acpi.c | 29 +++++++++++++++++++++++++++++ include/linux/acpi.h | 7 +++++++ 2 files changed, 36 insertions(+) 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 */ -- 2.20.1