gpio: add IRQ chip helpers in gpiolib
This provides a function gpiochip_irqchip_add() to set
up an irqchip for a GPIO controller, and a function
gpiochip_set_chained_irqchip() to chain it to a parent
irqchip.
Most GPIOs are of the type where a number of lines form
a cascaded interrupt controller chained onto
the primary system interrupt controller (or further down the
chain) so let's add this helper and factor the code to
request the lines to be used as IRQs, the .to_irq() function
and the irqdomain into the core as well.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 2e461e4..51c7825 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -55,6 +55,9 @@
def_bool y
depends on ACPI
+config GPIOLIB_IRQCHIP
+ bool
+
config DEBUG_GPIO
bool "Debug GPIO calls"
depends on DEBUG_KERNEL