linux-kernel - [PATCH v2] pinctrl: amd: disable and mask interrupts on probe

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Date:   Sat,  9 Oct 2021 14:32:40 +1100
From:   Sachi King <nakato@...ato.io>
To:     bnatikar@....com, mario.limonciello@....com
Cc:     linux-gpio@...r.kernel.org, Shyam-sundar.S-k@....com,
        Nehal-bakulchandra.Shah@....com, linus.walleij@...aro.org,
        linux-kernel@...r.kernel.org, nakato@...ato.io
Subject: [PATCH v2] 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>
---
Changes since v1:
- Removed duplicate INTERRUPT_MASK_OFF
- Corrected incorrect use of spaces instead of tab on third mask line
- Moved bitwise or to end of line to follow convention
- Corrected missing blank line after declaration
- Corrected open brace following function definitions
---
 drivers/pinctrl/pinctrl-amd.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c
index 8d0f88e9ca88..bae9d429b813 100644
--- a/drivers/pinctrl/pinctrl-amd.c
+++ b/drivers/pinctrl/pinctrl-amd.c
@@ -840,6 +840,34 @@ 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(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)
 {
@@ -976,6 +1004,9 @@ 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