diff options
Diffstat (limited to 'Documentation/driver-api/gpio/driver.rst')
| -rw-r--r-- | Documentation/driver-api/gpio/driver.rst | 27 |
1 files changed, 25 insertions, 2 deletions
diff --git a/Documentation/driver-api/gpio/driver.rst b/Documentation/driver-api/gpio/driver.rst index cbe0242842d1..a92d8837b62b 100644 --- a/Documentation/driver-api/gpio/driver.rst +++ b/Documentation/driver-api/gpio/driver.rst @@ -374,7 +374,28 @@ When implementing an irqchip inside a GPIO driver, these two functions should typically be called in the .startup() and .shutdown() callbacks from the irqchip. -When using the gpiolib irqchip helpers, these callback are automatically +When using the gpiolib irqchip helpers, these callbacks are automatically +assigned. + + +Disabling and enabling IRQs +--------------------------- +When a GPIO is used as an IRQ signal, then gpiolib also needs to know if +the IRQ is enabled or disabled. In order to inform gpiolib about this, +a driver should call:: + + void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset) + +This allows drivers to drive the GPIO as an output while the IRQ is +disabled. When the IRQ is enabled again, a driver should call:: + + void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset) + +When implementing an irqchip inside a GPIO driver, these two functions should +typically be called in the .irq_disable() and .irq_enable() callbacks from the +irqchip. + +When using the gpiolib irqchip helpers, these callbacks are automatically assigned. Real-Time compliance for GPIO IRQ chips @@ -413,7 +434,9 @@ try_module_get()). A GPIO driver can use the following functions instead to request and free descriptors without being pinned to the kernel forever:: struct gpio_desc *gpiochip_request_own_desc(struct gpio_desc *desc, - const char *label) + u16 hwnum, + const char *label, + enum gpiod_flags flags) void gpiochip_free_own_desc(struct gpio_desc *desc) |