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 <[email protected]>
---
I would prefer to avoid implementing irq_chip support, until there is a
real use case for this.
This has been tested with gpio-keys and gpiomon on the Koelsch
development board:
- gpio-keys, using a DT overlay[1]:
$ overlay add r8a7791-koelsch-keyboard-controlled-led
$ echo gpio-aggregator > /sys/devices/platform/frobnicator/driver_override
$ echo frobnicator > /sys/bus/platform/drivers/gpio-aggregator/bind
$ gpioinfo frobnicator
gpiochip12 - 3 lines:
line 0: "light" "light" output active-high [used]
line 1: "on" "On" input active-low [used]
line 2: "off" "Off" input active-low [used]
$ echo 255 > /sys/class/leds/light/brightness
$ echo 0 > /sys/class/leds/light/brightness
$ evtest /dev/input/event0
- gpiomon, using the GPIO sysfs API:
$ echo keyboard > /sys/bus/platform/drivers/gpio-keys/unbind
$ echo e6055800.gpio 2,6 > /sys/bus/platform/drivers/gpio-aggregator/new_device
$ gpiomon gpiochip12 0 1
[1] "ARM: dts: koelsch: Add overlay for keyboard-controlled LED"
https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git/commit/?h=topic/renesas-overlays&id=c78d817869e63a3485bb4ab98aeea6ce368a396e
---
drivers/gpio/gpio-aggregator.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
index e9671d1660ef4b40..869dc952cf45218b 100644
--- 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;
--
2.25.1
On Fri, Dec 3, 2021 at 3:06 PM Geert Uytterhoeven
<[email protected]> wrote:
>
> 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 <[email protected]>
> ---
> I would prefer to avoid implementing irq_chip support, until there is a
> real use case for this.
>
> This has been tested with gpio-keys and gpiomon on the Koelsch
> development board:
>
> - gpio-keys, using a DT overlay[1]:
>
> $ overlay add r8a7791-koelsch-keyboard-controlled-led
> $ echo gpio-aggregator > /sys/devices/platform/frobnicator/driver_override
> $ echo frobnicator > /sys/bus/platform/drivers/gpio-aggregator/bind
>
> $ gpioinfo frobnicator
> gpiochip12 - 3 lines:
> line 0: "light" "light" output active-high [used]
> line 1: "on" "On" input active-low [used]
> line 2: "off" "Off" input active-low [used]
>
> $ echo 255 > /sys/class/leds/light/brightness
> $ echo 0 > /sys/class/leds/light/brightness
>
> $ evtest /dev/input/event0
>
> - gpiomon, using the GPIO sysfs API:
>
> $ echo keyboard > /sys/bus/platform/drivers/gpio-keys/unbind
> $ echo e6055800.gpio 2,6 > /sys/bus/platform/drivers/gpio-aggregator/new_device
> $ gpiomon gpiochip12 0 1
>
> [1] "ARM: dts: koelsch: Add overlay for keyboard-controlled LED"
> https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git/commit/?h=topic/renesas-overlays&id=c78d817869e63a3485bb4ab98aeea6ce368a396e
> ---
> drivers/gpio/gpio-aggregator.c | 11 ++++++++++-
> 1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
> index e9671d1660ef4b40..869dc952cf45218b 100644
> --- 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;
> --
> 2.25.1
>
Applied, thanks!
Bart
On Fri, Dec 3, 2021 at 3:56 PM Bartosz Golaszewski <[email protected]> wrote:
>
> On Fri, Dec 3, 2021 at 3:06 PM Geert Uytterhoeven
> <[email protected]> wrote:
> >
> > 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 <[email protected]>
> > ---
> > I would prefer to avoid implementing irq_chip support, until there is a
> > real use case for this.
> >
> > This has been tested with gpio-keys and gpiomon on the Koelsch
> > development board:
> >
> > - gpio-keys, using a DT overlay[1]:
> >
> > $ overlay add r8a7791-koelsch-keyboard-controlled-led
> > $ echo gpio-aggregator > /sys/devices/platform/frobnicator/driver_override
> > $ echo frobnicator > /sys/bus/platform/drivers/gpio-aggregator/bind
> >
> > $ gpioinfo frobnicator
> > gpiochip12 - 3 lines:
> > line 0: "light" "light" output active-high [used]
> > line 1: "on" "On" input active-low [used]
> > line 2: "off" "Off" input active-low [used]
> >
> > $ echo 255 > /sys/class/leds/light/brightness
> > $ echo 0 > /sys/class/leds/light/brightness
> >
> > $ evtest /dev/input/event0
> >
> > - gpiomon, using the GPIO sysfs API:
> >
> > $ echo keyboard > /sys/bus/platform/drivers/gpio-keys/unbind
> > $ echo e6055800.gpio 2,6 > /sys/bus/platform/drivers/gpio-aggregator/new_device
> > $ gpiomon gpiochip12 0 1
> >
> > [1] "ARM: dts: koelsch: Add overlay for keyboard-controlled LED"
> > https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git/commit/?h=topic/renesas-overlays&id=c78d817869e63a3485bb4ab98aeea6ce368a396e
> > ---
> > drivers/gpio/gpio-aggregator.c | 11 ++++++++++-
> > 1 file changed, 10 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
> > index e9671d1660ef4b40..869dc952cf45218b 100644
> > --- 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;
> > --
> > 2.25.1
> >
>
> Applied, thanks!
>
> Bart
Eek, missed the explanation.
I think this is fine. For user-space eventual switch to a real
irq_chip won't break anything so let's take it.
Bart