gpio/omap: fix incorrect access of debounce module

Enable debounce clock before writing/reading debounce registers.
Disable the clock at the end so that it is synchronized with the
pm_runtime_get/put_sync calls.

Enable debounce clock per module. This call is mandatory because
in omap_gpio_request() when *_runtime_get_sync() is called,
_gpio_dbck_enable() within runtime callbck fails to turn on dbck
 because dbck_enable_mask used within _gpio_dbck_enable() is still
not initialized at that point. Therefore we have to enable dbck here.

Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>

1 files changed, 13 insertions, 5 deletions

diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index 69e61aecab71..8aeb8dd4342b 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -203,22 +203,30 @@ static void _set_gpio_debounce(struct gpio_bank *bank, unsigned gpio,
 
         l = GPIO_BIT(bank, gpio);
 
+        clk_enable(bank->dbck);
         reg = bank->base + bank->regs->debounce;
         __raw_writel(debounce, reg);
 
         reg = bank->base + bank->regs->debounce_en;
         val = __raw_readl(reg);
 
-        if (debounce) {
+        if (debounce)
                 val |= l;
-                clk_enable(bank->dbck);
-        } else {
+        else
                 val &= ~l;
-                clk_disable(bank->dbck);
-        }
         bank->dbck_enable_mask = val;
 
         __raw_writel(val, reg);
+        clk_disable(bank->dbck);
+        /*
+         * Enable debounce clock per module.
+         * This call is mandatory because in omap_gpio_request() when
+         * *_runtime_get_sync() is called,  _gpio_dbck_enable() within
+         * runtime callbck fails to turn on dbck because dbck_enable_mask
+         * used within _gpio_dbck_enable() is still not initialized at
+         * that point. Therefore we have to enable dbck here.
+         */
+        _gpio_dbck_enable(bank);
 }
 
 static inline void set_gpio_trigger(struct gpio_bank *bank, int gpio,