diff mbox series

[PATCHv2,5/6] gpio/driver.rst: document gpiochip_disable/enable_irq()

Message ID 20180908092319.43900-6-hverkuil@xs4all.nl
State New
Headers show
Series gpiolib: track irq enabled/disabled state | expand

Commit Message

Hans Verkuil Sept. 8, 2018, 9:23 a.m. UTC 
From: Hans Verkuil <hans.verkuil@cisco.com>

Document these new functions.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 Documentation/driver-api/gpio/driver.rst | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/Documentation/driver-api/gpio/driver.rst b/Documentation/driver-api/gpio/driver.rst
index cbe0242842d1..a6c14ff0c54f 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