[PATCH] gpio: mpc8xxx: Add wake on GPIO support

[PATCH] gpio: mpc8xxx: Add wake on GPIO support

[Martyn Welch]

The mpc8xxx GPIO can generate an interrupt on state change. This
interrupt can be used to wake up the device from its sleep state if
enabled to do so. Add required support to the driver so that the GPIO
can be used in this way.

In order for the GPIO to actually function in this way, it is necessary
to also set the GPIO bit in the RCPM. This can be done via the device
tree fsl,rcpm-wakeup property.

Signed-off-by: Martyn Welch <martyn.welch@collabora.com>
---
 drivers/gpio/gpio-mpc8xxx.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/gpio/gpio-mpc8xxx.c b/drivers/gpio/gpio-mpc8xxx.c
index c0125ac73906..ab30c911c9d5 100644
--- a/drivers/gpio/gpio-mpc8xxx.c
+++ b/drivers/gpio/gpio-mpc8xxx.c
@@ -413,6 +413,8 @@ static int mpc8xxx_probe(struct platform_device *pdev)
 		goto err;
 	}
 
+	device_init_wakeup(&pdev->dev, true);
+
 	return 0;
 err:
 	irq_domain_remove(mpc8xxx_gc->irq);
@@ -429,6 +431,31 @@ static void mpc8xxx_remove(struct platform_device *pdev)
 	}
 }
 
+#ifdef CONFIG_PM
+static int mpc8xxx_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
+
+	if (mpc8xxx_gc->irqn && device_may_wakeup(&pdev->dev))
+		enable_irq_wake(mpc8xxx_gc->irqn);
+
+	return 0;
+}
+
+static int mpc8xxx_resume(struct platform_device *pdev)
+{
+	struct mpc8xxx_gpio_chip *mpc8xxx_gc = platform_get_drvdata(pdev);
+
+	if (mpc8xxx_gc->irqn && device_may_wakeup(&pdev->dev))
+		disable_irq_wake(mpc8xxx_gc->irqn);
+
+	return 0;
+}
+#else
+#define mpc8xxx_suspend NULL
+#define mpc8xxx_resume NULL
+#endif
+
 #ifdef CONFIG_ACPI
 static const struct acpi_device_id gpio_acpi_ids[] = {
 	{"NXP0031",},
@@ -440,6 +467,8 @@ MODULE_DEVICE_TABLE(acpi, gpio_acpi_ids);
 static struct platform_driver mpc8xxx_plat_driver = {
 	.probe		= mpc8xxx_probe,
 	.remove_new	= mpc8xxx_remove,
+	.suspend	= mpc8xxx_suspend,
+	.resume		= mpc8xxx_resume,
 	.driver		= {
 		.name = "gpio-mpc8xxx",
 		.of_match_table	= mpc8xxx_gpio_ids,
-- 
2.43.0

Re: [PATCH] gpio: mpc8xxx: Add wake on GPIO support

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>


On Tue, 20 Aug 2024 15:33:27 +0100, Martyn Welch wrote:
> The mpc8xxx GPIO can generate an interrupt on state change. This
> interrupt can be used to wake up the device from its sleep state if
> enabled to do so. Add required support to the driver so that the GPIO
> can be used in this way.
> 
> In order for the GPIO to actually function in this way, it is necessary
> to also set the GPIO bit in the RCPM. This can be done via the device
> tree fsl,rcpm-wakeup property.
> 
> [...]

Applied, thanks!

[1/1] gpio: mpc8xxx: Add wake on GPIO support
      commit: 520aa57ad7222806ebdfd05b8de07bccd0156cf8

Best regards,
-- 
Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Re: [PATCH] gpio: mpc8xxx: Add wake on GPIO support

[Andy Shevchenko]

On Tue, Aug 20, 2024 at 03:33:27PM +0100, Martyn Welch wrote:
> The mpc8xxx GPIO can generate an interrupt on state change. This
> interrupt can be used to wake up the device from its sleep state if
> enabled to do so. Add required support to the driver so that the GPIO
> can be used in this way.
> 
> In order for the GPIO to actually function in this way, it is necessary
> to also set the GPIO bit in the RCPM. This can be done via the device
> tree fsl,rcpm-wakeup property.

Any specific requirement(s) to:
1) avoid new PM macros (such as pm_ptr());
2) use quite outdated PM callbacks?

-- 
With Best Regards,
Andy Shevchenko