1 files changed, 23 insertions, 10 deletions

diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c
index 41ccc759b8b8..1425c2874d40 100644
--- a/drivers/pinctrl/pinctrl-amd.c
+++ b/drivers/pinctrl/pinctrl-amd.c
@@ -348,21 +348,12 @@ static void amd_gpio_irq_enable(struct irq_data *d)
 	unsigned long flags;
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
-	u32 mask = BIT(INTERRUPT_ENABLE_OFF) | BIT(INTERRUPT_MASK_OFF);
 
 	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
 	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
 	pin_reg |= BIT(INTERRUPT_ENABLE_OFF);
 	pin_reg |= BIT(INTERRUPT_MASK_OFF);
 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
-	/*
-	 * When debounce logic is enabled it takes ~900 us before interrupts
-	 * can be enabled.  During this "debounce warm up" period the
-	 * "INTERRUPT_ENABLE" bit will read as 0. Poll the bit here until it
-	 * reads back as 1, signaling that interrupts are now enabled.
-	 */
-	while ((readl(gpio_dev->base + (d->hwirq)*4) & mask) != mask)
-		continue;
 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
 }
 
@@ -426,7 +417,7 @@ static void amd_gpio_irq_eoi(struct irq_data *d)
 static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 {
 	int ret = 0;
-	u32 pin_reg;
+	u32 pin_reg, pin_reg_irq_en, mask;
 	unsigned long flags, irq_flags;
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
@@ -495,6 +486,28 @@ static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 	}
 
 	pin_reg |= CLR_INTR_STAT << INTERRUPT_STS_OFF;
+	/*
+	 * If WAKE_INT_MASTER_REG.MaskStsEn is set, a software write to the
+	 * debounce registers of any GPIO will block wake/interrupt status
+	 * generation for *all* GPIOs for a lenght of time that depends on
+	 * WAKE_INT_MASTER_REG.MaskStsLength[11:0].  During this period the
+	 * INTERRUPT_ENABLE bit will read as 0.
+	 *
+	 * We temporarily enable irq for the GPIO whose configuration is
+	 * changing, and then wait for it to read back as 1 to know when
+	 * debounce has settled and then disable the irq again.
+	 * We do this polling with the spinlock held to ensure other GPIO
+	 * access routines do not read an incorrect value for the irq enable
+	 * bit of other GPIOs.  We keep the GPIO masked while polling to avoid
+	 * spurious irqs, and disable the irq again after polling.
+	 */
+	mask = BIT(INTERRUPT_ENABLE_OFF);
+	pin_reg_irq_en = pin_reg;
+	pin_reg_irq_en |= mask;
+	pin_reg_irq_en &= ~BIT(INTERRUPT_MASK_OFF);
+	writel(pin_reg_irq_en, gpio_dev->base + (d->hwirq)*4);
+	while ((readl(gpio_dev->base + (d->hwirq)*4) & mask) != mask)
+		continue;
 	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
 	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);