[PATCH] gpio: omap: Remove custom PM calls and use cpu_pm instead

[Tony Lindgren <tony@xxxxxxxxxxx>]

For a long time the gpio-omap custom PM calls have been annoying me so
let's replace them with cpu_pm instead. This will enable GPIO PM for
deeper idle states on omap4. And we can handle GPIO PM for omap2/3/4
in the same way.

Note that with this patch we are also slightly changing GPIO PM to be
less aggressive for omap3 and only will idle GPIO when PER context
may be lost.

For omap2, we don't need to save context and don't want to remove any
triggering so let's add a quirk flag for that.

Let's do this all in a single patch to avoid a situation where old
custom calls still are used with new code.

Cc: Aaro Koskinen <aaro.koskinen@xxxxxx>
Cc: Grygorii Strashko <grygorii.strashko@xxxxxx>
Cc: Keerthy <j-keerthy@xxxxxx>
Cc: Ladislav Michl <ladis@xxxxxxxxxxxxxx>
Cc: Tero Kristo <t-kristo@xxxxxx>
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
---

Note that this depends on previously posted patch:

[PATCH] gpio: omap: Add level wakeup handling for omap4 based SoCs

Linus, once people are happy with these, can you maybe set up an
immutable branch with both patches in it?

---
 arch/arm/mach-omap2/pm24xx.c            |  7 +--
 arch/arm/mach-omap2/pm34xx.c            | 14 ++---
 drivers/gpio/gpio-omap.c                | 78 +++++++++++++++----------
 include/linux/platform_data/gpio-omap.h | 13 -----
 4 files changed, 55 insertions(+), 57 deletions(-)

diff --git a/arch/arm/mach-omap2/pm24xx.c b/arch/arm/mach-omap2/pm24xx.c
--- a/arch/arm/mach-omap2/pm24xx.c
+++ b/arch/arm/mach-omap2/pm24xx.c
@@ -18,6 +18,7 @@
  * published by the Free Software Foundation.
  */
 
+#include <linux/cpu_pm.h>
 #include <linux/suspend.h>
 #include <linux/sched.h>
 #include <linux/proc_fs.h>
@@ -29,8 +30,6 @@
 #include <linux/clk-provider.h>
 #include <linux/irq.h>
 #include <linux/time.h>
-#include <linux/gpio.h>
-#include <linux/platform_data/gpio-omap.h>
 
 #include <asm/fncpy.h>
 
@@ -87,7 +86,7 @@ static int omap2_enter_full_retention(void)
 	l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
 	omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
 
-	omap2_gpio_prepare_for_idle(0);
+	cpu_cluster_pm_enter();
 
 	/* One last check for pending IRQs to avoid extra latency due
 	 * to sleeping unnecessarily. */
@@ -100,7 +99,7 @@ static int omap2_enter_full_retention(void)
 			   OMAP_SDRC_REGADDR(SDRC_POWER));
 
 no_sleep:
-	omap2_gpio_resume_after_idle();
+	cpu_cluster_pm_exit();
 
 	clk_enable(osc_ck);
 
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -18,19 +18,18 @@
  * published by the Free Software Foundation.
  */
 
+#include <linux/cpu_pm.h>
 #include <linux/pm.h>
 #include <linux/suspend.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/list.h>
 #include <linux/err.h>
-#include <linux/gpio.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/omap-dma.h>
 #include <linux/omap-gpmc.h>
-#include <linux/platform_data/gpio-omap.h>
 
 #include <trace/events/power.h>
 
@@ -197,7 +196,6 @@ void omap_sram_idle(void)
 	int mpu_next_state = PWRDM_POWER_ON;
 	int per_next_state = PWRDM_POWER_ON;
 	int core_next_state = PWRDM_POWER_ON;
-	int per_going_off;
 	u32 sdrc_pwr = 0;
 
 	mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
@@ -227,10 +225,8 @@ void omap_sram_idle(void)
 	pwrdm_pre_transition(NULL);
 
 	/* PER */
-	if (per_next_state < PWRDM_POWER_ON) {
-		per_going_off = (per_next_state == PWRDM_POWER_OFF) ? 1 : 0;
-		omap2_gpio_prepare_for_idle(per_going_off);
-	}
+	if (per_next_state == PWRDM_POWER_OFF)
+		cpu_cluster_pm_enter();
 
 	/* CORE */
 	if (core_next_state < PWRDM_POWER_ON) {
@@ -295,8 +291,8 @@ void omap_sram_idle(void)
 	pwrdm_post_transition(NULL);
 
 	/* PER */
-	if (per_next_state < PWRDM_POWER_ON)
-		omap2_gpio_resume_after_idle();
+	if (per_next_state == PWRDM_POWER_OFF)
+		cpu_cluster_pm_exit();
 }
 
 static void omap3_pm_idle(void)
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -19,6 +19,7 @@
 #include <linux/err.h>
 #include <linux/clk.h>
 #include <linux/io.h>
+#include <linux/cpu_pm.h>
 #include <linux/device.h>
 #include <linux/pm_runtime.h>
 #include <linux/pm.h>
@@ -31,6 +32,7 @@
 #define OFF_MODE	1
 #define OMAP4_GPIO_DEBOUNCINGTIME_MASK 0xFF
 
+#define OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER	BIT(2)
 #define OMAP_GPIO_QUIRK_DEFERRED_WKUP_EN	BIT(1)
 
 static LIST_HEAD(omap_gpio_list);
@@ -72,6 +74,7 @@ struct gpio_bank {
 	raw_spinlock_t wa_lock;
 	struct gpio_chip chip;
 	struct clk *dbck;
+	struct notifier_block nb;
 	u32 mod_usage;
 	u32 irq_usage;
 	u32 dbck_enable_mask;
@@ -1308,6 +1311,38 @@ static int omap_gpio_chip_init(struct gpio_bank *bank, struct irq_chip *irqc)
 	return ret;
 }
 
+static int gpio_omap_cpu_notifier(struct notifier_block *nb,
+				  unsigned long cmd, void *v)
+{
+	struct gpio_bank *bank;
+	struct device *dev;
+	int error;
+
+	bank = container_of(nb, struct gpio_bank, nb);
+	dev = bank->chip.parent;
+
+	switch (cmd) {
+	case CPU_CLUSTER_PM_ENTER:
+		/* Gets cleard on runtime_suspend */
+		bank->power_mode = OFF_MODE;
+
+		error = pm_runtime_put_sync(dev);
+		if (error < 0)
+			dev_warn(dev, "CPU PM enter: %i\n", error);
+		break;
+	case CPU_CLUSTER_PM_ENTER_FAILED:
+	case CPU_CLUSTER_PM_EXIT:
+		error = pm_runtime_get_sync(dev);
+		if (error < 0) {
+			dev_err(dev, "CPU PM exit %i\n", error);
+			pm_runtime_put_noidle(dev);
+		}
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
 static const struct of_device_id omap_gpio_match[];
 
 static int omap_gpio_probe(struct platform_device *pdev)
@@ -1445,6 +1480,9 @@ static int omap_gpio_probe(struct platform_device *pdev)
 
 	omap_gpio_show_rev(bank);
 
+	bank->nb.notifier_call = gpio_omap_cpu_notifier;
+	cpu_pm_register_notifier(&bank->nb);
+
 	pm_runtime_put(dev);
 
 	list_add_tail(&bank->node, &omap_gpio_list);
@@ -1456,6 +1494,7 @@ static int omap_gpio_remove(struct platform_device *pdev)
 {
 	struct gpio_bank *bank = platform_get_drvdata(pdev);
 
+	cpu_pm_unregister_notifier(&bank->nb);
 	list_del(&bank->node);
 	gpiochip_remove(&bank->chip);
 	pm_runtime_disable(&pdev->dev);
@@ -1622,37 +1661,7 @@ static int omap_gpio_runtime_resume(struct device *dev)
 
 	return 0;
 }
-#endif /* CONFIG_PM */
-
-#if IS_BUILTIN(CONFIG_GPIO_OMAP)
-void omap2_gpio_prepare_for_idle(int pwr_mode)
-{
-	struct gpio_bank *bank;
 
-	list_for_each_entry(bank, &omap_gpio_list, node) {
-		if (!BANK_USED(bank) || !bank->loses_context)
-			continue;
-
-		bank->power_mode = pwr_mode;
-
-		pm_runtime_put_sync_suspend(bank->chip.parent);
-	}
-}
-
-void omap2_gpio_resume_after_idle(void)
-{
-	struct gpio_bank *bank;
-
-	list_for_each_entry(bank, &omap_gpio_list, node) {
-		if (!BANK_USED(bank) || !bank->loses_context)
-			continue;
-
-		pm_runtime_get_sync(bank->chip.parent);
-	}
-}
-#endif
-
-#if defined(CONFIG_PM)
 static void omap_gpio_init_context(struct gpio_bank *p)
 {
 	struct omap_gpio_reg_offs *regs = p->regs;
@@ -1768,6 +1777,11 @@ static struct omap_gpio_reg_offs omap4_gpio_regs = {
 	.fallingdetect =	OMAP4_GPIO_FALLINGDETECT,
 };
 
+/*
+ * Note that omap2 does not currently support idle modes with context loss so
+ * no need to add OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER quirk flag to save
+ * and restore context.
+ */
 static const struct omap_gpio_platform_data omap2_pdata = {
 	.regs = &omap2_gpio_regs,
 	.bank_width = 32,
@@ -1778,13 +1792,15 @@ static const struct omap_gpio_platform_data omap3_pdata = {
 	.regs = &omap2_gpio_regs,
 	.bank_width = 32,
 	.dbck_flag = true,
+	.quirks = OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER,
 };
 
 static const struct omap_gpio_platform_data omap4_pdata = {
 	.regs = &omap4_gpio_regs,
 	.bank_width = 32,
 	.dbck_flag = true,
-	.quirks = OMAP_GPIO_QUIRK_DEFERRED_WKUP_EN,
+	.quirks = OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER |
+		  OMAP_GPIO_QUIRK_DEFERRED_WKUP_EN,
 };
 
 static const struct of_device_id omap_gpio_match[] = {
diff --git a/include/linux/platform_data/gpio-omap.h b/include/linux/platform_data/gpio-omap.h
--- a/include/linux/platform_data/gpio-omap.h
+++ b/include/linux/platform_data/gpio-omap.h
@@ -205,17 +205,4 @@ struct omap_gpio_platform_data {
 	int (*get_context_loss_count)(struct device *dev);
 };
 
-#if IS_BUILTIN(CONFIG_GPIO_OMAP)
-extern void omap2_gpio_prepare_for_idle(int off_mode);
-extern void omap2_gpio_resume_after_idle(void);
-#else
-static inline void omap2_gpio_prepare_for_idle(int off_mode)
-{
-}
-
-static inline void omap2_gpio_resume_after_idle(void)
-{
-}
-#endif
-
 #endif
-- 
2.18.0