[PATCH v2 3/5] drivers: pinctrl: msm: enable PDC interrupt only during suspend

[Lina Iyer]

During suspend the system may power down some of the system rails. As a
result, the TLMM hw block may not be operational anymore and wakeup
capable GPIOs will not be detected. The PDC however will be operational
and the GPIOs that are routed to the PDC as IRQs can wake the system up.

To avoid being interrupted twice (for TLMM and once for PDC IRQ) when a
GPIO trips, use TLMM for active and switch to PDC for suspend. When
entering suspend, disable the TLMM wakeup interrupt and instead enable
the PDC IRQ and revert upon resume.

Signed-off-by: Lina Iyer <ilina@xxxxxxxxxxxxxx>
---
 drivers/pinctrl/qcom/pinctrl-msm.c | 60 +++++++++++++++++++++++++++++-
 drivers/pinctrl/qcom/pinctrl-msm.h |  3 ++
 2 files changed, 62 insertions(+), 1 deletion(-)

diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index 03ef1d29d078..17e541f8f09d 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -37,6 +37,7 @@
 #include "../pinctrl-utils.h"
 
 #define MAX_NR_GPIO 300
+#define MAX_PDC_IRQ 1024
 #define PS_HOLD_OFFSET 0x820
 
 /**
@@ -51,6 +52,7 @@
  * @enabled_irqs:   Bitmap of currently enabled irqs.
  * @dual_edge_irqs: Bitmap of irqs that need sw emulated dual edge
  *                  detection.
+ * @pdc_irqs:       Bitmap of wakeup capable irqs.
  * @soc;            Reference to soc_data of platform specific data.
  * @regs:           Base address for the TLMM register map.
  */
@@ -68,11 +70,14 @@ struct msm_pinctrl {
 
 	DECLARE_BITMAP(dual_edge_irqs, MAX_NR_GPIO);
 	DECLARE_BITMAP(enabled_irqs, MAX_NR_GPIO);
+	DECLARE_BITMAP(pdc_irqs, MAX_PDC_IRQ);
 
 	const struct msm_pinctrl_soc_data *soc;
 	void __iomem *regs;
 };
 
+static bool in_suspend;
+
 static int msm_get_groups_count(struct pinctrl_dev *pctldev)
 {
 	struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
@@ -787,8 +792,11 @@ static int msm_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
 
 	raw_spin_lock_irqsave(&pctrl->lock, flags);
 
-	if (pdc_irqd)
+	if (pdc_irqd && !in_suspend) {
 		irq_set_irq_wake(pdc_irqd->irq, on);
+		on ? set_bit(pdc_irqd->irq, pctrl->pdc_irqs) :
+		     clear_bit(pdc_irqd->irq, pctrl->pdc_irqs);
+	}
 
 	irq_set_irq_wake(pctrl->irq, on);
 
@@ -920,6 +928,8 @@ static int msm_gpio_pdc_pin_request(struct irq_data *d)
 	}
 
 	irq_set_handler_data(d->irq, irq_get_irq_data(irq));
+	irq_set_handler_data(irq, d);
+	irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY);
 	disable_irq(irq);
 
 	return 0;
@@ -1070,6 +1080,54 @@ static void msm_pinctrl_setup_pm_reset(struct msm_pinctrl *pctrl)
 		}
 }
 
+int __maybe_unused msm_pinctrl_suspend_late(struct device *dev)
+{
+	struct msm_pinctrl *pctrl = dev_get_drvdata(dev);
+	struct irq_data *irqd;
+	int i;
+
+	in_suspend = true;
+	for_each_set_bit(i, pctrl->pdc_irqs, MAX_PDC_IRQ) {
+		irqd = irq_get_handler_data(i);
+		/*
+		 * We don't know if the TLMM will be functional
+		 * or not, during the suspend. If its functional,
+		 * we do not want duplicate interrupts from PDC.
+		 * Hence disable the GPIO IRQ and enable PDC IRQ.
+		 */
+		if (irqd_is_wakeup_set(irqd)) {
+			irq_set_irq_wake(irqd->irq, false);
+			disable_irq(irqd->irq);
+			enable_irq(i);
+		}
+	}
+
+	return 0;
+}
+
+int __maybe_unused msm_pinctrl_resume_late(struct device *dev)
+{
+	struct msm_pinctrl *pctrl = dev_get_drvdata(dev);
+	struct irq_data *irqd;
+	int i;
+
+	for_each_set_bit(i, pctrl->pdc_irqs, MAX_PDC_IRQ) {
+		irqd = irq_get_handler_data(i);
+		/*
+		 * The TLMM will be operational now, so disable
+		 * the PDC IRQ.
+		 */
+		if (irqd_is_wakeup_set(irq_get_irq_data(i))) {
+			disable_irq_nosync(i);
+			irq_set_irq_wake(irqd->irq, true);
+			enable_irq(irqd->irq);
+		}
+	}
+	in_suspend = false;
+
+	return 0;
+}
+
 int msm_pinctrl_probe(struct platform_device *pdev,
 		      const struct msm_pinctrl_soc_data *soc_data)
 {
diff --git a/drivers/pinctrl/qcom/pinctrl-msm.h b/drivers/pinctrl/qcom/pinctrl-msm.h
index 9b9feea540ff..21b56fb5dae9 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.h
+++ b/drivers/pinctrl/qcom/pinctrl-msm.h
@@ -123,4 +123,7 @@ int msm_pinctrl_probe(struct platform_device *pdev,
 		      const struct msm_pinctrl_soc_data *soc_data);
 int msm_pinctrl_remove(struct platform_device *pdev);
 
+int msm_pinctrl_suspend_late(struct device *dev);
+int msm_pinctrl_resume_late(struct device *dev);
+
 #endif
-- 
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