Merge tag 'pinctrl-v5.8-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin control fix from Linus Walleij:
 "A single last minute pin control fix to the Qualcomm driver fixing
  missing dual edge PCH interrupts"

* tag 'pinctrl-v5.8-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: qcom: Handle broken/missing PDC dual edge IRQs on sc7180

Author: torvalds

drivers/pinctrl/qcom/Kconfig

@@ -7,6 +7,8 @@ config PINCTRL_MSM
 	select PINCONF
 	select GENERIC_PINCONF
 	select GPIOLIB_IRQCHIP
+	select IRQ_DOMAIN_HIERARCHY
+	select IRQ_FASTEOI_HIERARCHY_HANDLERS
 
 config PINCTRL_APQ8064
 	tristate "Qualcomm APQ8064 pin controller driver"

drivers/pinctrl/qcom/pinctrl-msm.c

@@ -832,6 +832,52 @@ static void msm_gpio_irq_unmask(struct irq_data *d)
 	msm_gpio_irq_clear_unmask(d, false);
 }
 
+/**
+ * msm_gpio_update_dual_edge_parent() - Prime next edge for IRQs handled by parent.
+ * @d: The irq dta.
+ *
+ * This is much like msm_gpio_update_dual_edge_pos() but for IRQs that are
+ * normally handled by the parent irqchip.  The logic here is slightly
+ * different due to what's easy to do with our parent, but in principle it's
+ * the same.
+ */
+static void msm_gpio_update_dual_edge_parent(struct irq_data *d)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
+	const struct msm_pingroup *g = &pctrl->soc->groups[d->hwirq];
+	int loop_limit = 100;
+	unsigned int val;
+	unsigned int type;
+
+	/* Read the value and make a guess about what edge we need to catch */
+	val = msm_readl_io(pctrl, g) & BIT(g->in_bit);
+	type = val ? IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING;
+
+	do {
+		/* Set the parent to catch the next edge */
+		irq_chip_set_type_parent(d, type);
+
+		/*
+		 * Possibly the line changed between when we last read "val"
+		 * (and decided what edge we needed) and when set the edge.
+		 * If the value didn't change (or changed and then changed
+		 * back) then we're done.
+		 */
+		val = msm_readl_io(pctrl, g) & BIT(g->in_bit);
+		if (type == IRQ_TYPE_EDGE_RISING) {
+			if (!val)
+				return;
+			type = IRQ_TYPE_EDGE_FALLING;
+		} else if (type == IRQ_TYPE_EDGE_FALLING) {
+			if (val)
+				return;
+			type = IRQ_TYPE_EDGE_RISING;
+		}
+	} while (loop_limit-- > 0);
+	dev_warn_once(pctrl->dev, "dual-edge irq failed to stabilize\n");
+}
+
 static void msm_gpio_irq_ack(struct irq_data *d)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
@@ -840,8 +886,11 @@ static void msm_gpio_irq_ack(struct irq_data *d)
 	unsigned long flags;
 	u32 val;
 
-	if (test_bit(d->hwirq, pctrl->skip_wake_irqs))
+	if (test_bit(d->hwirq, pctrl->skip_wake_irqs)) {
+		if (test_bit(d->hwirq, pctrl->dual_edge_irqs))
+			msm_gpio_update_dual_edge_parent(d);
 		return;
+	}
 
 	g = &pctrl->soc->groups[d->hwirq];
 
@@ -860,6 +909,17 @@ static void msm_gpio_irq_ack(struct irq_data *d)
 	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 }
 
+static bool msm_gpio_needs_dual_edge_parent_workaround(struct irq_data *d,
+						       unsigned int type)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
+
+	return type == IRQ_TYPE_EDGE_BOTH &&
+	       pctrl->soc->wakeirq_dual_edge_errata && d->parent_data &&
+	       test_bit(d->hwirq, pctrl->skip_wake_irqs);
+}
+
 static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
@@ -868,11 +928,21 @@ static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 	unsigned long flags;
 	u32 val;
 
+	if (msm_gpio_needs_dual_edge_parent_workaround(d, type)) {
+		set_bit(d->hwirq, pctrl->dual_edge_irqs);
+		irq_set_handler_locked(d, handle_fasteoi_ack_irq);
+		msm_gpio_update_dual_edge_parent(d);
+		return 0;
+	}
+
 	if (d->parent_data)
 		irq_chip_set_type_parent(d, type);
 
-	if (test_bit(d->hwirq, pctrl->skip_wake_irqs))
+	if (test_bit(d->hwirq, pctrl->skip_wake_irqs)) {
+		clear_bit(d->hwirq, pctrl->dual_edge_irqs);
+		irq_set_handler_locked(d, handle_fasteoi_irq);
 		return 0;
+	}
 
 	g = &pctrl->soc->groups[d->hwirq];
 

drivers/pinctrl/qcom/pinctrl-msm.h

@@ -113,6 +113,9 @@ struct msm_gpio_wakeirq_map {
  * @pull_no_keeper: The SoC does not support keeper bias.
  * @wakeirq_map:    The map of wakeup capable GPIOs and the pin at PDC/MPM
  * @nwakeirq_map:   The number of entries in @wakeirq_map
+ * @wakeirq_dual_edge_errata: If true then GPIOs using the wakeirq_map need
+ *                            to be aware that their parent can't handle dual
+ *                            edge interrupts.
  */
 struct msm_pinctrl_soc_data {
 	const struct pinctrl_pin_desc *pins;
@@ -128,6 +131,7 @@ struct msm_pinctrl_soc_data {
 	const int *reserved_gpios;
 	const struct msm_gpio_wakeirq_map *wakeirq_map;
 	unsigned int nwakeirq_map;
+	bool wakeirq_dual_edge_errata;
 };
 
 extern const struct dev_pm_ops msm_pinctrl_dev_pm_ops;

drivers/pinctrl/qcom/pinctrl-sc7180.c

@@ -1147,6 +1147,7 @@ static const struct msm_pinctrl_soc_data sc7180_pinctrl = {
 	.ntiles = ARRAY_SIZE(sc7180_tiles),
 	.wakeirq_map = sc7180_pdc_map,
 	.nwakeirq_map = ARRAY_SIZE(sc7180_pdc_map),
+	.wakeirq_dual_edge_errata = true,
 };
 
 static int sc7180_pinctrl_probe(struct platform_device *pdev)