spmi: pmic-arb: support show_resume_irq

show_resume_irq is used to debug interrupts that cause wakeup.
Support it for spmi arbiter's interrupt controller.

Change-Id: I52d51c09d7ff316248542c84a1cd65a28e2283da
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>

drivers/spmi/spmi-pmic-arb.c

@@ -24,6 +24,7 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/spmi.h>
+#include <linux/syscore_ops.h>
 
 /* PMIC Arbiter configuration registers */
 #define PMIC_ARB_VERSION		0x0000
@@ -159,6 +160,7 @@ struct spmi_pmic_arb {
 	u16			last_apid;
 	struct apid_data	apid_data[PMIC_ARB_MAX_PERIPHS];
 };
+static struct spmi_pmic_arb *the_pa;
 
 /**
  * pmic_arb_ver: version dependent functionality.
@@ -525,7 +527,7 @@ static void cleanup_irq(struct spmi_pmic_arb *pa, u16 apid, int id)
 				irq_mask, ppid);
 }
 
-static void periph_interrupt(struct spmi_pmic_arb *pa, u16 apid)
+static void periph_interrupt(struct spmi_pmic_arb *pa, u16 apid, bool show)
 {
 	unsigned int irq;
 	u32 status;
@@ -542,22 +544,32 @@ static void periph_interrupt(struct spmi_pmic_arb *pa, u16 apid)
 			cleanup_irq(pa, apid, id);
 			continue;
 		}
+		if (show) {
+			struct irq_desc *desc;
+			const char *name = "null";
+
+			desc = irq_to_desc(irq);
+			if (desc == NULL)
+				name = "stray irq";
+			else if (desc->action && desc->action->name)
+				name = desc->action->name;
+
+			pr_warn("spmi_show_resume_irq: %d triggered [0x%01x, 0x%02x, 0x%01x] %s\n",
+				irq, sid, per, id, name);
+		} else {
 			generic_handle_irq(irq);
 		}
 	}
+}
 
-static void pmic_arb_chained_irq(struct irq_desc *desc)
+static void __pmic_arb_chained_irq(struct spmi_pmic_arb *pa, bool show)
 {
-	struct spmi_pmic_arb *pa = irq_desc_get_handler_data(desc);
-	struct irq_chip *chip = irq_desc_get_chip(desc);
 	void __iomem *intr = pa->intr;
 	int first = pa->min_apid >> 5;
 	int last = pa->max_apid >> 5;
 	u32 status, enable;
 	int i, id, apid;
 
-	chained_irq_enter(chip, desc);
-
 	for (i = first; i <= last; ++i) {
 		status = readl_relaxed(intr +
 				      pa->ver_ops->owner_acc_status(pa->ee, i));
@@ -568,10 +580,18 @@ static void pmic_arb_chained_irq(struct irq_desc *desc)
 			enable = readl_relaxed(intr +
 					pa->ver_ops->acc_enable(apid));
 			if (enable & SPMI_PIC_ACC_ENABLE_BIT)
-				periph_interrupt(pa, apid);
+				periph_interrupt(pa, apid, show);
+		}
 	}
 }
 
+static void pmic_arb_chained_irq(struct irq_desc *desc)
+{
+	struct spmi_pmic_arb *pa = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+
+	chained_irq_enter(chip, desc);
+	__pmic_arb_chained_irq(pa, false);
 	chained_irq_exit(chip, desc);
 }
 
@@ -988,6 +1008,16 @@ static const struct irq_domain_ops pmic_arb_irq_domain_ops = {
 	.xlate	= qpnpint_irq_domain_dt_translate,
 };
 
+static void spmi_pmic_arb_resume(void)
+{
+	if (spmi_show_resume_irq())
+		__pmic_arb_chained_irq(the_pa, true);
+}
+
+static struct syscore_ops spmi_pmic_arb_syscore_ops = {
+	.resume = spmi_pmic_arb_resume,
+};
+
 static int spmi_pmic_arb_probe(struct platform_device *pdev)
 {
 	struct spmi_pmic_arb *pa;
@@ -1153,6 +1183,8 @@ static int spmi_pmic_arb_probe(struct platform_device *pdev)
 	if (err)
 		goto err_domain_remove;
 
+	the_pa = pa;
+	register_syscore_ops(&spmi_pmic_arb_syscore_ops);
 	return 0;
 
 err_domain_remove:
@@ -1167,8 +1199,11 @@ static int spmi_pmic_arb_remove(struct platform_device *pdev)
 {
 	struct spmi_controller *ctrl = platform_get_drvdata(pdev);
 	struct spmi_pmic_arb *pa = spmi_controller_get_drvdata(ctrl);
+
 	spmi_controller_remove(ctrl);
 	irq_set_chained_handler_and_data(pa->irq, NULL, NULL);
+	unregister_syscore_ops(&spmi_pmic_arb_syscore_ops);
+	the_pa = NULL;
 	irq_domain_remove(pa->domain);
 	spmi_controller_put(ctrl);
 	return 0;

include/linux/spmi.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2012-2016, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -171,6 +171,19 @@ static inline void spmi_driver_unregister(struct spmi_driver *sdrv)
 	module_driver(__spmi_driver, spmi_driver_register, \
 			spmi_driver_unregister)
 
+#ifdef CONFIG_QCOM_SHOW_RESUME_IRQ
+extern int msm_show_resume_irq_mask;
+static inline bool spmi_show_resume_irq(void)
+{
+	return msm_show_resume_irq_mask;
+}
+#else
+static inline bool spmi_show_resume_irq(void)
+{
+	return false;
+}
+#endif
+
 int spmi_register_read(struct spmi_device *sdev, u8 addr, u8 *buf);
 int spmi_ext_register_read(struct spmi_device *sdev, u8 addr, u8 *buf,
 			   size_t len);