[PATCH 2/2] pinctrl: amd: Mask non-wake source pins with interrupt enabled at suspend

[Mario Limonciello <mario.limonciello@amd.com>]

If a pin isn't marked as a wake source processing any interrupts is
just going to destroy battery life.  The APU may wake up from a hardware
sleep state to process the interrupt but not return control to the OS.

Mask interrupt for all non-wake source pins at suspend. They'll be
re-enabled at resume.

Reported-and-tested-by: Marcus Aram <marcus+oss@oxar.nl>
Reported-and-tested-by: Mark Herbert <mark.herbert42@gmail.com>
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2812
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 drivers/pinctrl/pinctrl-amd.c | 9 +++++++++
 drivers/pinctrl/pinctrl-amd.h | 5 +++++
 2 files changed, 14 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c
index fb58acb843d9..03ecb3d1aaf6 100644
--- a/drivers/pinctrl/pinctrl-amd.c
+++ b/drivers/pinctrl/pinctrl-amd.c
@@ -923,6 +923,15 @@ static int amd_gpio_suspend(struct device *dev)
 
 		raw_spin_lock_irqsave(&gpio_dev->lock, flags);
 		gpio_dev->saved_regs[i] = readl(gpio_dev->base + pin * 4) & ~PIN_IRQ_PENDING;
+
+		/* mask any interrupts not intended to be a wake source */
+		if (!(gpio_dev->saved_regs[i] & WAKE_SOURCE)) {
+			writel(gpio_dev->saved_regs[i] & ~BIT(INTERRUPT_MASK_OFF),
+			       gpio_dev->base + pin * 4);
+			pm_pr_dbg("Disabling GPIO #%d interrupt for suspend.\n",
+				  pin);
+		}
+
 		raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
 	}
 
diff --git a/drivers/pinctrl/pinctrl-amd.h b/drivers/pinctrl/pinctrl-amd.h
index 34c5c3e71fb2..cf59089f2776 100644
--- a/drivers/pinctrl/pinctrl-amd.h
+++ b/drivers/pinctrl/pinctrl-amd.h
@@ -80,6 +80,11 @@
 #define FUNCTION_MASK		GENMASK(1, 0)
 #define FUNCTION_INVALID	GENMASK(7, 0)
 
+#define WAKE_SOURCE	(BIT(WAKE_CNTRL_OFF_S0I3) | \
+			 BIT(WAKE_CNTRL_OFF_S3)   | \
+			 BIT(WAKE_CNTRL_OFF_S4)   | \
+			 BIT(WAKECNTRL_Z_OFF))
+
 struct amd_function {
 	const char *name;
 	const char * const groups[NSELECTS];
-- 
2.34.1