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authorHans Verkuil <hans.verkuil@cisco.com>2018-09-08 11:23:18 +0200
committerLinus Walleij <linus.walleij@linaro.org>2018-09-10 08:57:01 +0200
commit4f8183ae7092fe3a6985b9a10a5d7f3efa01b097 (patch)
tree699af6a15cdbe8a094134c991395686fb04f6600 /Documentation/driver-api
parent461c1a7d4733d1dfd5c47b040cf32a5e7eefbc6c (diff)
downloadblackbird-op-linux-4f8183ae7092fe3a6985b9a10a5d7f3efa01b097.tar.gz
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gpio/driver.rst: document gpiochip_disable/enable_irq()
Document these new functions. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'Documentation/driver-api')
-rw-r--r--Documentation/driver-api/gpio/driver.rst23
1 files changed, 22 insertions, 1 deletions
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
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