linux-kernel - [PATCH 1/1] pinctrl: amd: disable and mask interrupts on probe

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Message-Id: <20211001161714.2053597-2-nakato@nakato.io>
Date:   Sat,  2 Oct 2021 02:17:14 +1000
From:   Sachi King <nakato@...ato.io>
To:     linux-gpio@...r.kernel.org, basavaraj.natikar@....com
Cc:     linux-kernel@...r.kernel.org, Sachi King <nakato@...ato.io>
Subject: [PATCH 1/1] pinctrl: amd: disable and mask interrupts on probe

Some systems such as the Microsoft Surface Laptop 4 leave interrupts
enabled and configured for use in sleep states on boot, which cause
unexpected behaviour such as spurious wakes and failed resumes in
s2idle states.

As interrupts should not be enabled until they are claimed and
explicitly enabled, disabling any interrupts mistakenly left enabled by
firmware should be safe.

Signed-off-by: Sachi King <nakato@...ato.io>
---
 drivers/pinctrl/pinctrl-amd.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c
index c001f2ed20f8..aa4136cd312d 100644
--- a/drivers/pinctrl/pinctrl-amd.c
+++ b/drivers/pinctrl/pinctrl-amd.c
@@ -830,6 +830,32 @@ static const struct pinconf_ops amd_pinconf_ops = {
 	.pin_config_group_set = amd_pinconf_group_set,
 };
 
+static void amd_gpio_irq_init(struct amd_gpio *gpio_dev) {
+	struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
+	unsigned long flags;
+	u32 pin_reg, mask;
+	int i;
+
+	mask = BIT(WAKE_CNTRL_OFF_S0I3) | BIT(WAKE_CNTRL_OFF_S3)
+		| BIT(INTERRUPT_MASK_OFF) | BIT(INTERRUPT_ENABLE_OFF)
+	        | BIT(INTERRUPT_MASK_OFF) | BIT(WAKE_CNTRL_OFF_S4);
+
+	for (i = 0; i < desc->npins; i++) {
+		int pin = desc->pins[i].number;
+		const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);
+		if (!pd)
+			continue;
+
+		raw_spin_lock_irqsave(&gpio_dev->lock, flags);
+
+		pin_reg = readl(gpio_dev->base + i * 4);
+		pin_reg &= ~mask;
+		writel(pin_reg, gpio_dev->base + i * 4);
+
+		raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
+	}
+}
+
 #ifdef CONFIG_PM_SLEEP
 static bool amd_gpio_should_save(struct amd_gpio *gpio_dev, unsigned int pin)
 {
@@ -967,6 +993,9 @@ static int amd_gpio_probe(struct platform_device *pdev)
 		return PTR_ERR(gpio_dev->pctrl);
 	}
 
+	/* Disable and mask interrupts */
+	amd_gpio_irq_init(gpio_dev);
+
 	girq = &gpio_dev->gc.irq;
 	girq->chip = &amd_gpio_irqchip;
 	/* This will let us handle the parent IRQ in the driver */
-- 
2.33.0