gpio: mvebu: convert to noirq suspend/resume to prevent interrupt storm on resume

The driver uses the legacy .suspend/.resume callbacks, but sets IRQCHIP_MASK_ON_SUSPEND on the irq_chip. During resume, the PM core runs dpm_resume_noirq() first, which calls irq_pm_resume() to unmask interrupts, and only then runs dpm_resume() which invokes the driver's .resume callback to restore GPIO registers (GPIO_IN_POL, GPIO_IO_CONF, mask registers).

This ordering means interrupts are unmasked while the hardware is still in its reset state, potentially with incorrect polarities, causing spurious level-triggered interrupts before local IRQs are re-enabled.

Convert the driver from legacy .suspend/.resume callbacks to noirq callbacks via dev_pm_ops. The noirq phase runs before resume_device_irqs() on resume and after suspend_device_irqs() on suspend, ensuring GPIO registers are restored before interrupts are unmasked.

Assisted-by opencode:big-pickle

Signed-off-by Rosen Penev <[email protected]>

---
v2: add __maybe_unused to fix compilation

 drivers/gpio/gpio-mvebu.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

drivers/gpio/gpio-mvebu.c +9 -7

index 7094ab34020c..bd31acf779e6 100644
@@ -979,9 +979,9 @@ static const struct of_device_id mvebu_gpio_of_match[] = {
        },
 };
 
-static int mvebu_gpio_suspend(struct platform_device *pdev, pm_message_t state)
+static __maybe_unused int mvebu_gpio_suspend(struct device *dev)
 {
-       struct mvebu_gpio_chip *mvchip = platform_get_drvdata(pdev);
+       struct mvebu_gpio_chip *mvchip = dev_get_drvdata(dev);
        int i;
 
        regmap_read(mvchip->regs, GPIO_OUT_OFF + mvchip->offset,

@@ -1031,9 +1031,9 @@ static int mvebu_gpio_suspend(struct platform_device *pdev, pm_message_t state)
        return 0;
 }
 
-static int mvebu_gpio_resume(struct platform_device *pdev)
+static __maybe_unused int mvebu_gpio_resume(struct device *dev)
 {
-       struct mvebu_gpio_chip *mvchip = platform_get_drvdata(pdev);
+       struct mvebu_gpio_chip *mvchip = dev_get_drvdata(dev);
        int i;
 
        regmap_write(mvchip->regs, GPIO_OUT_OFF + mvchip->offset,

@@ -1339,13 +1339,16 @@ static int mvebu_gpio_probe(struct platform_device *pdev)
        return 0;
 }
 
+static const struct dev_pm_ops mvebu_gpio_pm_ops = {
+       SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mvebu_gpio_suspend, mvebu_gpio_resume)
+};
+
 static struct platform_driver mvebu_gpio_driver = {
        .driver         = {
                .name           = "mvebu-gpio",
                .of_match_table = mvebu_gpio_of_match,
+               .pm             = pm_sleep_ptr(&mvebu_gpio_pm_ops),
        },
        .probe          = mvebu_gpio_probe,
-       .suspend        = mvebu_gpio_suspend,
-       .resume         = mvebu_gpio_resume,
 };
 builtin_platform_driver(mvebu_gpio_driver);
--

2.55.0

The driver uses the legacy .suspend/.resume callbacks, but sets IRQCHIP_MASK_ON_SUSPEND on the irq_chip. During resume, the PM core runs dpm_resume_noirq() first, which calls irq_pm_resume() to unmask interrupts, and only then runs dpm_resume() which invokes the driver's .resume callback to restore GPIO registers (GPIO_IN_POL, GPIO_IO_CONF, mask registers).

This ordering means interrupts are unmasked while the hardware is still in its reset state, potentially with incorrect polarities, causing spurious level-triggered interrupts before local IRQs are re-enabled.

Convert the driver from legacy .suspend/.resume callbacks to noirq callbacks via dev_pm_ops. The noirq phase runs before resume_device_irqs() on resume and after suspend_device_irqs() on suspend, ensuring GPIO registers are restored before interrupts are unmasked.

Assisted-by opencode:big-pickle

Signed-off-by Rosen Penev <[email protected]>

Quoted 16 lines · Rosen Penev

The driver uses the legacy .suspend/.resume callbacks, but sets IRQCHIP_MASK_ON_SUSPEND on the irq_chip. During resume, the PM core runs dpm_resume_noirq() first, which calls irq_pm_resume() to unmask interrupts, and only then runs dpm_resume() which invokes the driver's .resume callback to restore GPIO registers (GPIO_IN_POL, GPIO_IO_CONF, mask registers).

This ordering means interrupts are unmasked while the hardware is still in its reset state, potentially with incorrect polarities, causing spurious level-triggered interrupts before local IRQs are re-enabled.

Convert the driver from legacy .suspend/.resume callbacks to noirq callbacks via dev_pm_ops. The noirq phase runs before resume_device_irqs() on resume and after suspend_device_irqs() on suspend, ensuring GPIO registers are restored before interrupts are unmasked.

Quoted 1 line

Assisted-by opencode:big-pickle

Should be

Assisted-by LLM

these days (Bartosz can probs fix when applying)

Quoted 2 lines

Signed-off-by Rosen Penev <[email protected]>

Reviewed-by Linus Walleij <[email protected]>

Yours,
Linus Walleij