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path: root/drivers/gpio/gpio-omap.c
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Diffstat (limited to 'drivers/gpio/gpio-omap.c')
-rw-r--r--drivers/gpio/gpio-omap.c34
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index afef0f7c..c48de8f 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -1206,8 +1206,30 @@ static int omap_gpio_runtime_suspend(struct device *dev)
struct gpio_bank *bank = platform_get_drvdata(pdev);
u32 l1 = 0, l2 = 0;
unsigned long flags;
+ u32 wake_low, wake_hi;
spin_lock_irqsave(&bank->lock, flags);
+
+ /*
+ * Only edges can generate a wakeup event to the PRCM.
+ *
+ * Therefore, ensure any wake-up capable GPIOs have
+ * edge-detection enabled before going idle to ensure a wakeup
+ * to the PRCM is generated on a GPIO transition. (c.f. 34xx
+ * NDA TRM 25.5.3.1)
+ *
+ * The normal values will be restored upon ->runtime_resume()
+ * by writing back the values saved in bank->context.
+ */
+ wake_low = bank->context.leveldetect0 & bank->context.wake_en;
+ if (wake_low)
+ __raw_writel(wake_low | bank->context.fallingdetect,
+ bank->base + bank->regs->fallingdetect);
+ wake_hi = bank->context.leveldetect1 & bank->context.wake_en;
+ if (wake_hi)
+ __raw_writel(wake_hi | bank->context.risingdetect,
+ bank->base + bank->regs->risingdetect);
+
if (bank->power_mode != OFF_MODE) {
bank->power_mode = 0;
goto update_gpio_context_count;
@@ -1256,6 +1278,18 @@ static int omap_gpio_runtime_resume(struct device *dev)
spin_lock_irqsave(&bank->lock, flags);
_gpio_dbck_enable(bank);
+
+ /*
+ * In ->runtime_suspend(), level-triggered, wakeup-enabled
+ * GPIOs were set to edge trigger also in order to be able to
+ * generate a PRCM wakeup. Here we restore the
+ * pre-runtime_suspend() values for edge triggering.
+ */
+ __raw_writel(bank->context.fallingdetect,
+ bank->base + bank->regs->fallingdetect);
+ __raw_writel(bank->context.risingdetect,
+ bank->base + bank->regs->risingdetect);
+
if (!bank->enabled_non_wakeup_gpios || !bank->workaround_enabled) {
spin_unlock_irqrestore(&bank->lock, flags);
return 0;
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