gpio: aggregator: Add interrupt support

Currently the GPIO Aggregator does not support interrupts.  This means
that kernel drivers going from a GPIO to an IRQ using gpiod_to_irq(),
and userspace applications using line events do not work.

Add interrupt support by providing a gpio_chip.to_irq() callback, which
just calls into the parent GPIO controller.

Note that this does not implement full interrupt controller (irq_chip)
support, so using e.g. gpio-keys with "interrupts" instead of "gpios"
still does not work.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
index e9671d1660ef4b4006dcdc6865a502d0fc0c89bc..869dc952cf45218b7cc7c295f31ea730aaab836a 100644 (file)
--- a/drivers/gpio/gpio-aggregator.c
+++ b/drivers/gpio/gpio-aggregator.c
@@ -371,6 +371,13 @@ static int gpio_fwd_set_config(struct gpio_chip *chip, unsigned int offset,
        return gpiod_set_config(fwd->descs[offset], config);
 }
 
+static int gpio_fwd_to_irq(struct gpio_chip *chip, unsigned int offset)
+{
+       struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+       return gpiod_to_irq(fwd->descs[offset]);
+}
+
 /**
  * gpiochip_fwd_create() - Create a new GPIO forwarder
  * @dev: Parent device pointer
@@ -411,7 +418,8 @@ static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
        for (i = 0; i < ngpios; i++) {
                struct gpio_chip *parent = gpiod_to_chip(descs[i]);
 
-               dev_dbg(dev, "%u => gpio-%d\n", i, desc_to_gpio(descs[i]));
+               dev_dbg(dev, "%u => gpio %d irq %d\n", i,
+                       desc_to_gpio(descs[i]), gpiod_to_irq(descs[i]));
 
                if (gpiod_cansleep(descs[i]))
                        chip->can_sleep = true;
@@ -429,6 +437,7 @@ static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
        chip->get_multiple = gpio_fwd_get_multiple_locked;
        chip->set = gpio_fwd_set;
        chip->set_multiple = gpio_fwd_set_multiple_locked;
+       chip->to_irq = gpio_fwd_to_irq;
        chip->base = -1;
        chip->ngpio = ngpios;
        fwd->descs = descs;