[PATCH 0/2] Input: gpio-keys - support wakeup pinctrl state

[PATCH 0/2] Input: gpio-keys - support wakeup pinctrl state

[Kendall Willis]

Add 'wakeup' pinctrl state to support separate pin wakeup
configurations for GPIO. Upon suspend the 'wakeup' pinctrl state is
chosen if it exists. On resume the 'default' pinctrl state is selected.
The 'wakeup' pinctrl state allows wakeup from low-power states if a
specific pin configuration is needed.

On TI K3 AM62 family of devices, the GPIO controller is turned off in
suspend to RAM states, so no interrupt can be received by the
controller. This prevents system wakeup from low-power states.
Alternatively, the pins can wakeup the system if a wakeup flag is set on
the pin by using pinctrl.

A corresponding device tree patch using the 'wakeup' pinctrl state can
be found under "arm64: dts: ti: k3-am62l3-evm: add wakeup-source for GPIO
button".

Tested GPIO wakeup from suspend on AM62L EVM and AM62P EVM.

Signed-off-by: Kendall Willis <k-willis@ti.com>
---
Kendall Willis (2):
      dt-bindings: input: gpio-keys: add pinctrl states
      Input: gpio-keys - support wakeup pinctrl state on suspend

 Documentation/devicetree/bindings/input/gpio-keys.yaml | 16 ++++++++++++++++
 drivers/input/keyboard/gpio_keys.c                     | 13 +++++++++++++
 2 files changed, 29 insertions(+)
---
base-commit: df2908090cda368b01ff43709f51890076c56157
change-id: 20260904-upstream-gpio-wakeup-52a54080c948

Best regards,
-- 
Kendall Willis <k-willis@ti.com>

[PATCH 1/2] dt-bindings: input: gpio-keys: add pinctrl states

[Kendall Willis]

Document pinctrl properties on the gpio-keys device node. By using the
wakeup pinctrl state, the pins are able to wakeup the system from a
low-power state. The default pinctrl state describes the default pin
configuration.

Signed-off-by: Kendall Willis <k-willis@ti.com>
---
 Documentation/devicetree/bindings/input/gpio-keys.yaml | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Documentation/devicetree/bindings/input/gpio-keys.yaml b/Documentation/devicetree/bindings/input/gpio-keys.yaml
index cc78c2152921308fe0cad3e29ca78a5fad08f066..b554933e93412d8b6c2ec401dc1e1eeff57d4190 100644
--- a/Documentation/devicetree/bindings/input/gpio-keys.yaml
+++ b/Documentation/devicetree/bindings/input/gpio-keys.yaml
@@ -22,6 +22,22 @@ properties:
 
   poll-interval: true
 
+  pinctrl-0:
+    description: Default pinctrl state
+
+  pinctrl-1:
+    description: Wakeup pinctrl state
+
+  pinctrl-names:
+    description:
+      When present should contain at least "default" describing the default pin
+      states. The second state called "wakeup" describes the pins in their
+      wakeup configuration required to exit sleep states.
+    minItems: 1
+    items:
+      - const: default
+      - const: wakeup
+
 patternProperties:
   "^(button|event|key|switch|(button|event|key|switch)-[a-z0-9-]+|[a-z0-9-]+-(button|event|key|switch))$":
     $ref: input.yaml#

-- 
2.34.1

[PATCH 2/2] Input: gpio-keys - support wakeup pinctrl state on suspend

[Kendall Willis]

GPIO can be used as a wakeup source for TI K3 AM62 devices during
suspend to RAM states. The GPIO controller is powered off in these
states, so a wakeup enable flag must be set on the GPIO pin in the
pinctrl in order to allow wakeup.

If the device is wakeup enabled, select the 'wakeup' pinctrl state on
suspend and restore the default pinctrl state on resume.

Signed-off-by: Kendall Willis <k-willis@ti.com>
---
 drivers/input/keyboard/gpio_keys.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
index 129fc4212a5ed126496b331ce626682d441c53bf..b409e179705195e5fec172ff62088395109cd758 100644
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -28,6 +28,7 @@
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/spinlock.h>
+#include <linux/pinctrl/consumer.h>
 #include <dt-bindings/input/gpio-keys.h>
 
 struct gpio_button_data {
@@ -60,6 +61,8 @@ struct gpio_keys_drvdata {
 	struct input_dev *input;
 	struct mutex disable_lock;
 	unsigned short *keymap;
+	struct pinctrl *pinctrl;
+	struct pinctrl_state *pinctrl_wakeup;
 	struct gpio_button_data data[];
 };
 
@@ -884,6 +887,10 @@ static int gpio_keys_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, ddata);
 	input_set_drvdata(input, ddata);
 
+	ddata->pinctrl = devm_pinctrl_get(dev);
+	if (!IS_ERR_OR_NULL(ddata->pinctrl))
+		ddata->pinctrl_wakeup = pinctrl_lookup_state(ddata->pinctrl, "wakeup");
+
 	input->name = pdata->name ? : pdev->name;
 	input->phys = "gpio-keys/input0";
 	input->dev.parent = dev;
@@ -1010,6 +1017,9 @@ gpio_keys_enable_wakeup(struct gpio_keys_drvdata *ddata)
 	int error;
 	int i;
 
+	if (!IS_ERR_OR_NULL(ddata->pinctrl_wakeup))
+		pinctrl_select_state(ddata->pinctrl, ddata->pinctrl_wakeup);
+
 	for (i = 0; i < ddata->pdata->nbuttons; i++) {
 		bdata = &ddata->data[i];
 		if (bdata->button->wakeup) {
@@ -1039,6 +1049,9 @@ gpio_keys_disable_wakeup(struct gpio_keys_drvdata *ddata)
 	struct gpio_button_data *bdata;
 	int i;
 
+	if (!IS_ERR_OR_NULL(ddata->pinctrl_wakeup))
+		pinctrl_pm_select_default_state(ddata->input->dev.parent);
+
 	for (i = 0; i < ddata->pdata->nbuttons; i++) {
 		bdata = &ddata->data[i];
 		bdata->suspended = false;

-- 
2.34.1

Re: [PATCH 1/2] dt-bindings: input: gpio-keys: add pinctrl states

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Schema constraint on `pinctrl-names` breaks validation for existing device trees using standard PM states.
--

commit 7cccd8c7baf951e7fe028bb369bca736764010d5
Author: Kendall Willis <k-willis@ti.com>

dt-bindings: input: gpio-keys: add pinctrl states

This patch adds pinctrl-0, pinctrl-1, and pinctrl-names properties to the
gpio-keys device tree binding to document the default and wakeup pin
configurations.

> diff --git a/Documentation/devicetree/bindings/input/gpio-keys.yaml b/Documentation/devicetree/bindings/input/gpio-keys.yaml
> index cc78c21529213..b554933e93412 100644
> --- a/Documentation/devicetree/bindings/input/gpio-keys.yaml
> +++ b/Documentation/devicetree/bindings/input/gpio-keys.yaml
[ ... ]
> +  pinctrl-names:
> +    description:
> +      When present should contain at least "default" describing the default pin
> +      states. The second state called "wakeup" describes the pins in their
> +      wakeup configuration required to exit sleep states.
> +    minItems: 1
> +    items:
> +      - const: default
> +      - const: wakeup

[Severity: Medium]
Does this strict schema constraint break validation for existing device trees?

By explicitly restricting the pinctrl-names items to exactly "default" and
"wakeup" in Documentation/devicetree/bindings/input/gpio-keys.yaml, this
generic binding will now cause device tree validation (make dtbs_check) to
fail for existing upstream boards. 

Many boards correctly use standard pinctrl power management states like "sleep"
(for example, pinctrl-names = "default", "sleep";) which are now rejected by
this schema.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260912-upstream-gpio-wakeup-v1-0-f0e12484b836@ti.com?part=1

Re: [PATCH 2/2] Input: gpio-keys - support wakeup pinctrl state on suspend

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Missing restoration of default pinctrl state on error path in gpio_keys_enable_wakeup().
--

commit 794b05f8c21f23224e4ff7b076c2d675310e6432
Author: Kendall Willis <k-willis@ti.com>

Input: gpio-keys - support wakeup pinctrl state on suspend

This commit enables GPIO controllers on TI K3 AM62 devices to act as a wakeup
source during suspend to RAM by selecting a wakeup pinctrl state and restoring
the default on resume.

> diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
> index 129fc4212a5ed..b409e17970519 100644
> --- a/drivers/input/keyboard/gpio_keys.c
> +++ b/drivers/input/keyboard/gpio_keys.c

[ ... ]

> @@ -1010,6 +1017,9 @@ gpio_keys_enable_wakeup(struct gpio_keys_drvdata *ddata)
>  	int error;
>  	int i;
>  
> +	if (!IS_ERR_OR_NULL(ddata->pinctrl_wakeup))
> +		pinctrl_select_state(ddata->pinctrl, ddata->pinctrl_wakeup);
> +
>  	for (i = 0; i < ddata->pdata->nbuttons; i++) {
>  		bdata = &ddata->data[i];
>  		if (bdata->button->wakeup) {

[Severity: Medium]
Does the error path in this function need to restore the default pinctrl
state?

Looking at gpio_keys_enable_wakeup in drivers/input/keyboard/gpio_keys.c,
the pinctrl state is changed to wakeup at the start of the function.
However, if gpio_keys_button_enable_wakeup fails for any button, the code
jumps to the err_out label:

err_out:
        while (i--) {
                bdata = &ddata->data[i];
                if (bdata->button->wakeup)
                        gpio_keys_button_disable_wakeup(bdata);
                bdata->suspended = false;
        }

        return error;

Since a failure here aborts the device's suspend transition, the PM core
will not invoke the corresponding resume callback. Could this leave the
hardware pins stuck in the wakeup configuration instead of reverting to the
default state for normal runtime operation?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260912-upstream-gpio-wakeup-v1-0-f0e12484b836@ti.com?part=2