GPIO: OMAP: set edge trigger for wakeup gpio

Only edge trigger is supported for wakeup.
if a gpio is set as wakeup, and level trigger,
make sure we set the edge trigger so that we
can wake up.

Change-Id: Ibb61042be6ce053729ff20f3cb8d53899afe42b1
Signed-off-by: Axel Haslam <axelhaslam@ti.com>

3 files changed, 53 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c
index 7e2b3c8..8ffc139 100644
--- a/arch/arm/mach-omap2/pm44xx.c
+++ b/arch/arm/mach-omap2/pm44xx.c
@@ -165,6 +165,8 @@ void omap4_enter_sleep(unsigned int cpu, unsigned int power_state, bool suspend)
 		}
 	}
 
+	omap2_gpio_set_edge_wakeup();
+
 	if (omap4_device_next_state_off()) {
 		omap2_gpio_prepare_for_idle(true);
 		omap_gpmc_save_context();
@@ -233,6 +235,8 @@ abort_device_off:
 			OMAP4430_PRM_DEVICE_INST, OMAP4_PRM_IO_PMCTRL_OFFSET);
 	}
 
+	omap2_gpio_restore_edge_wakeup();
+
 	if (mpu_next_state < PWRDM_POWER_INACTIVE) {
 		omap_vc_set_auto_trans(mpu_voltdm,
 				OMAP_VC_CHANNEL_AUTO_TRANSITION_DISABLE);
diff --git a/arch/arm/plat-omap/include/plat/gpio.h b/arch/arm/plat-omap/include/plat/gpio.h
index 24b61af..89af4ad 100644
--- a/arch/arm/plat-omap/include/plat/gpio.h
+++ b/arch/arm/plat-omap/include/plat/gpio.h
@@ -217,6 +217,8 @@ extern void omap2_gpio_prepare_for_idle(int off_mode);
 extern void omap2_gpio_resume_after_idle(void);
 extern void omap_set_gpio_debounce(int gpio, int enable);
 extern void omap_set_gpio_debounce_time(int gpio, int enable);
+extern void omap2_gpio_set_edge_wakeup(void);
+extern void omap2_gpio_restore_edge_wakeup(void);
 /*-------------------------------------------------------------------------*/
 
 /* Wrappers for "new style" GPIO calls, using the new infrastructure
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index a06a054..312d45d 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -44,6 +44,8 @@ struct gpio_regs {
 	u32 dataout;
 	u32 debounce;
 	u32 debounce_en;
+	u32 edge_falling;
+	u32 edge_rising;
 };
 
 struct gpio_bank {
@@ -1383,6 +1385,51 @@ static int omap_gpio_pm_runtime_resume(struct device *dev)
 }
 
 #ifdef CONFIG_ARCH_OMAP2PLUS
+void omap2_gpio_set_edge_wakeup(void)
+{
+	struct gpio_bank *bank;
+
+	list_for_each_entry(bank, &omap_gpio_list, node) {
+		u32 level_low = 0;
+		u32 level_high = 0;
+		u32 wkup_status = 0;
+
+		level_low = __raw_readl(bank->base +
+				bank->regs->leveldetect0);
+		level_high = __raw_readl(bank->base +
+				bank->regs->leveldetect1);
+		wkup_status = __raw_readl(bank->base +
+				bank->regs->wkup_status);
+		bank->context.edge_falling = __raw_readl(bank->base +
+				bank->regs->fallingdetect);
+		bank->context.edge_rising = __raw_readl(bank->base +
+				bank->regs->risingdetect);
+
+		/*
+		 * Set edge trigger for all gpio's that are
+		 * expected to produce wakeup from low power.
+		 * even if they are set for level detection only.
+		 */
+		__raw_writel((bank->context.edge_falling | level_low) & wkup_status,
+			(bank->base + bank->regs->fallingdetect));
+		__raw_writel((bank->context.edge_rising | level_high) & wkup_status,
+			(bank->base + bank->regs->risingdetect));
+
+	}
+}
+
+void omap2_gpio_restore_edge_wakeup(void)
+{
+	struct gpio_bank *bank;
+
+	list_for_each_entry(bank, &omap_gpio_list, node) {
+		/* restore edge setting */
+		__raw_writel(bank->context.edge_falling,
+			(bank->base + bank->regs->fallingdetect));
+		__raw_writel(bank->context.edge_rising,
+			(bank->base + bank->regs->risingdetect));
+	}
+}
 
 void omap2_gpio_prepare_for_idle(int off_mode)
 {