Allow configuring an optional dedicated wakeirq for gpio-keys that
some SoCs have.
Let's use the common interrupt naming "irq" and "wakeup" that we already
have in use for some drivers and subsystems like i2c framework.
Note that the gpio-keys interrupt property is optional. If only a gpio
property is specified, the driver tries to translate the gpio into an
interrupt.
Reviewed-by: Rob Herring <[email protected]>
Signed-off-by: Tony Lindgren <[email protected]>
---
No changes since v3
Changes since v2:
- Fix indentation as noted by Rob's bot
- Add Reviewed-by from Rob
Changes since v1:
- Run make dt_binding_check on the binding
- Add better checks for interrupt-names as suggested by Rob, it is
now required if two interrupts are configured
- Add more decription entries
- Add a new example for key-wakeup
---
.../devicetree/bindings/input/gpio-keys.yaml | 41 ++++++++++++++++++-
1 file changed, 40 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/input/gpio-keys.yaml b/Documentation/devicetree/bindings/input/gpio-keys.yaml
--- a/Documentation/devicetree/bindings/input/gpio-keys.yaml
+++ b/Documentation/devicetree/bindings/input/gpio-keys.yaml
@@ -31,7 +31,23 @@ patternProperties:
maxItems: 1
interrupts:
- maxItems: 1
+ oneOf:
+ - items:
+ - description: Optional key interrupt or wakeup interrupt
+ - items:
+ - description: Key interrupt
+ - description: Wakeup interrupt
+
+ interrupt-names:
+ description:
+ Optional interrupt names, can be used to specify a separate dedicated
+ wake-up interrupt in addition to the gpio irq
+ oneOf:
+ - items:
+ - enum: [ irq, wakeup ]
+ - items:
+ - const: irq
+ - const: wakeup
label:
description: Descriptive name of the key.
@@ -97,6 +113,20 @@ patternProperties:
- required:
- gpios
+ allOf:
+ - if:
+ properties:
+ interrupts:
+ minItems: 2
+ required:
+ - interrupts
+ then:
+ properties:
+ interrupt-names:
+ minItems: 2
+ required:
+ - interrupt-names
+
dependencies:
wakeup-event-action: [ wakeup-source ]
linux,input-value: [ gpios ]
@@ -137,6 +167,15 @@ examples:
linux,code = <108>;
interrupts = <1 IRQ_TYPE_EDGE_FALLING>;
};
+
+ key-wakeup {
+ label = "GPIO Key WAKEUP";
+ linux,code = <143>;
+ interrupts-extended = <&intc 2 IRQ_TYPE_EDGE_FALLING>,
+ <&intc_wakeup 0 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-names = "irq", "wakeup";
+ wakeup-source;
+ };
};
...
--
2.42.1
Some SoCs have a separate dedicated wake-up interrupt controller that can
be used to wake up the system from deeper idle states. We already support
configuring a separate interrupt for a gpio-keys button to be used with a
gpio line. However, we are lacking support system suspend for cases where
a separate interrupt needs to be used in deeper sleep modes.
Because of it's nature, gpio-keys does not know about the runtime PM state
of the button gpios, and may have several gpio buttons configured for each
gpio-keys device instance. Implementing runtime PM support for gpio-keys
does not help, and we cannot use drivers/base/power/wakeirq.c support. We
need to implement custom wakeirq support for gpio-keys.
For handling a dedicated wakeirq for system suspend, we enable and disable
it with gpio_keys_enable_wakeup() and gpio_keys_disable_wakeup() that we
already use based on device_may_wakeup().
Some systems may have a dedicated wakeirq that can also be used as the
main interrupt, this is already working for gpio-keys. Let's add some
wakeirq related comments while at it as the usage with a gpio line and
separate interrupt line may not be obvious.
Tested-by: Dhruva Gole <[email protected]>
Signed-off-by: Tony Lindgren <[email protected]>
---
Changes since v5
- Use normal disable_irq() as suggested by Dmitry
No driver changes between v1 and v4
---
drivers/input/keyboard/gpio_keys.c | 69 ++++++++++++++++++++++++++++--
include/linux/gpio_keys.h | 2 +
2 files changed, 67 insertions(+), 4 deletions(-)
diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -45,7 +45,9 @@ struct gpio_button_data {
unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */
unsigned int irq;
+ unsigned int wakeirq;
unsigned int wakeup_trigger_type;
+
spinlock_t lock;
bool disabled;
bool key_pressed;
@@ -511,6 +513,7 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
struct gpio_button_data *bdata = &ddata->data[idx];
irq_handler_t isr;
unsigned long irqflags;
+ const char *wakedesc;
int irq;
int error;
@@ -575,6 +578,14 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
!gpiod_cansleep(bdata->gpiod);
}
+ /*
+ * If an interrupt was specified, use it instead of the gpio
+ * interrupt and use the gpio for reading the state. A separate
+ * interrupt may be used as the main button interrupt for
+ * runtime PM to detect events also in deeper idle states. If a
+ * dedicated wakeirq is used for system suspend only, see below
+ * for bdata->wakeirq setup.
+ */
if (button->irq) {
bdata->irq = button->irq;
} else {
@@ -672,6 +683,36 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
return error;
}
+ if (!button->wakeirq)
+ return 0;
+
+ /* Use :wakeup suffix like drivers/base/power/wakeirq.c does */
+ wakedesc = devm_kasprintf(dev, GFP_KERNEL, "%s:wakeup", desc);
+ if (!wakedesc)
+ return -ENOMEM;
+
+ bdata->wakeirq = button->wakeirq;
+ irqflags |= IRQF_NO_SUSPEND;
+
+ /*
+ * Wakeirq shares the handler with the main interrupt, it's only
+ * active during system suspend. See gpio_keys_button_enable_wakeup()
+ * and gpio_keys_button_disable_wakeup().
+ */
+ error = devm_request_any_context_irq(dev, bdata->wakeirq, isr,
+ irqflags, wakedesc, bdata);
+ if (error < 0) {
+ dev_err(dev, "Unable to claim wakeirq %d; error %d\n",
+ bdata->irq, error);
+ return error;
+ }
+
+ /*
+ * Disable wakeirq until suspend. IRQF_NO_AUTOEN won't work if
+ * IRQF_SHARED was set based on !button->can_disable.
+ */
+ disable_irq(bdata->wakeirq);
+
return 0;
}
@@ -728,7 +769,7 @@ gpio_keys_get_devtree_pdata(struct device *dev)
struct gpio_keys_platform_data *pdata;
struct gpio_keys_button *button;
struct fwnode_handle *child;
- int nbuttons;
+ int nbuttons, irq;
nbuttons = device_get_child_node_count(dev);
if (nbuttons == 0)
@@ -750,9 +791,19 @@ gpio_keys_get_devtree_pdata(struct device *dev)
device_property_read_string(dev, "label", &pdata->name);
device_for_each_child_node(dev, child) {
- if (is_of_node(child))
- button->irq =
- irq_of_parse_and_map(to_of_node(child), 0);
+ if (is_of_node(child)) {
+ irq = of_irq_get_byname(to_of_node(child), "irq");
+ if (irq > 0)
+ button->irq = irq;
+
+ irq = of_irq_get_byname(to_of_node(child), "wakeup");
+ if (irq > 0)
+ button->wakeirq = irq;
+
+ if (!button->irq && !button->wakeirq)
+ button->irq =
+ irq_of_parse_and_map(to_of_node(child), 0);
+ }
if (fwnode_property_read_u32(child, "linux,code",
&button->code)) {
@@ -921,6 +972,11 @@ gpio_keys_button_enable_wakeup(struct gpio_button_data *bdata)
}
}
+ if (bdata->wakeirq) {
+ enable_irq(bdata->wakeirq);
+ disable_irq(bdata->irq);
+ }
+
return 0;
}
@@ -929,6 +985,11 @@ gpio_keys_button_disable_wakeup(struct gpio_button_data *bdata)
{
int error;
+ if (bdata->wakeirq) {
+ enable_irq(bdata->irq);
+ disable_irq(bdata->wakeirq);
+ }
+
/*
* The trigger type is always both edges for gpio-based keys and we do
* not support changing wakeup trigger for interrupt-based keys.
diff --git a/include/linux/gpio_keys.h b/include/linux/gpio_keys.h
--- a/include/linux/gpio_keys.h
+++ b/include/linux/gpio_keys.h
@@ -21,6 +21,7 @@ struct device;
* disable button via sysfs
* @value: axis value for %EV_ABS
* @irq: Irq number in case of interrupt keys
+ * @wakeirq: Optional dedicated wake-up interrupt
*/
struct gpio_keys_button {
unsigned int code;
@@ -34,6 +35,7 @@ struct gpio_keys_button {
bool can_disable;
int value;
unsigned int irq;
+ unsigned int wakeirq;
};
/**
--
2.42.1
On Wed, Nov 29, 2023 at 01:06:15PM +0200, Tony Lindgren wrote:
> Some SoCs have a separate dedicated wake-up interrupt controller that can
> be used to wake up the system from deeper idle states. We already support
> configuring a separate interrupt for a gpio-keys button to be used with a
> gpio line. However, we are lacking support system suspend for cases where
> a separate interrupt needs to be used in deeper sleep modes.
>
> Because of it's nature, gpio-keys does not know about the runtime PM state
> of the button gpios, and may have several gpio buttons configured for each
> gpio-keys device instance. Implementing runtime PM support for gpio-keys
> does not help, and we cannot use drivers/base/power/wakeirq.c support. We
> need to implement custom wakeirq support for gpio-keys.
>
> For handling a dedicated wakeirq for system suspend, we enable and disable
> it with gpio_keys_enable_wakeup() and gpio_keys_disable_wakeup() that we
> already use based on device_may_wakeup().
>
> Some systems may have a dedicated wakeirq that can also be used as the
> main interrupt, this is already working for gpio-keys. Let's add some
> wakeirq related comments while at it as the usage with a gpio line and
> separate interrupt line may not be obvious.
>
> Tested-by: Dhruva Gole <[email protected]>
> Signed-off-by: Tony Lindgren <[email protected]>
Applied, thank you.
--
Dmitry
On Wed, Nov 29, 2023 at 01:06:14PM +0200, Tony Lindgren wrote:
> Allow configuring an optional dedicated wakeirq for gpio-keys that
> some SoCs have.
>
> Let's use the common interrupt naming "irq" and "wakeup" that we already
> have in use for some drivers and subsystems like i2c framework.
>
> Note that the gpio-keys interrupt property is optional. If only a gpio
> property is specified, the driver tries to translate the gpio into an
> interrupt.
>
> Reviewed-by: Rob Herring <[email protected]>
> Signed-off-by: Tony Lindgren <[email protected]>
Applied, thank you.
--
Dmitry