[PATCH 4.9 59/66] pinctrl: baytrail: Rectify debounce support

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

commit 04ff5a095d662e0879f0eb04b9247e092210aeff upstream.

The commit 658b476c742f ("pinctrl: baytrail: Add debounce configuration")
implements debounce for Baytrail pin control, but seems wasn't tested properly.

The register which keeps debounce value is separated from the configuration
one. Writing wrong values to the latter will guarantee wrong behaviour of the
driver and even might break something physically.

Besides above there is missed case how to disable it, which is actually done
through the bit in configuration register.

Rectify implementation here by using proper register for debounce value.

Fixes: 658b476c742f ("pinctrl: baytrail: Add debounce configuration")
Cc: Cristina Ciocan <cristina.ciocan@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/pinctrl/intel/pinctrl-baytrail.c |   28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

--- a/drivers/pinctrl/intel/pinctrl-baytrail.c
+++ b/drivers/pinctrl/intel/pinctrl-baytrail.c
@@ -1092,6 +1092,7 @@ static int byt_pin_config_get(struct pin
 	enum pin_config_param param = pinconf_to_config_param(*config);
 	void __iomem *conf_reg = byt_gpio_reg(vg, offset, BYT_CONF0_REG);
 	void __iomem *val_reg = byt_gpio_reg(vg, offset, BYT_VAL_REG);
+	void __iomem *db_reg = byt_gpio_reg(vg, offset, BYT_DEBOUNCE_REG);
 	unsigned long flags;
 	u32 conf, pull, val, debounce;
 	u16 arg = 0;
@@ -1128,7 +1129,7 @@ static int byt_pin_config_get(struct pin
 			return -EINVAL;
 
 		raw_spin_lock_irqsave(&vg->lock, flags);
-		debounce = readl(byt_gpio_reg(vg, offset, BYT_DEBOUNCE_REG));
+		debounce = readl(db_reg);
 		raw_spin_unlock_irqrestore(&vg->lock, flags);
 
 		switch (debounce & BYT_DEBOUNCE_PULSE_MASK) {
@@ -1176,6 +1177,7 @@ static int byt_pin_config_set(struct pin
 	unsigned int param, arg;
 	void __iomem *conf_reg = byt_gpio_reg(vg, offset, BYT_CONF0_REG);
 	void __iomem *val_reg = byt_gpio_reg(vg, offset, BYT_VAL_REG);
+	void __iomem *db_reg = byt_gpio_reg(vg, offset, BYT_DEBOUNCE_REG);
 	unsigned long flags;
 	u32 conf, val, debounce;
 	int i, ret = 0;
@@ -1238,36 +1240,40 @@ static int byt_pin_config_set(struct pin
 
 			break;
 		case PIN_CONFIG_INPUT_DEBOUNCE:
-			debounce = readl(byt_gpio_reg(vg, offset,
-						      BYT_DEBOUNCE_REG));
-			conf &= ~BYT_DEBOUNCE_PULSE_MASK;
+			debounce = readl(db_reg);
+			debounce &= ~BYT_DEBOUNCE_PULSE_MASK;
 
 			switch (arg) {
+			case 0:
+				conf &= BYT_DEBOUNCE_EN;
+				break;
 			case 375:
-				conf |= BYT_DEBOUNCE_PULSE_375US;
+				debounce |= BYT_DEBOUNCE_PULSE_375US;
 				break;
 			case 750:
-				conf |= BYT_DEBOUNCE_PULSE_750US;
+				debounce |= BYT_DEBOUNCE_PULSE_750US;
 				break;
 			case 1500:
-				conf |= BYT_DEBOUNCE_PULSE_1500US;
+				debounce |= BYT_DEBOUNCE_PULSE_1500US;
 				break;
 			case 3000:
-				conf |= BYT_DEBOUNCE_PULSE_3MS;
+				debounce |= BYT_DEBOUNCE_PULSE_3MS;
 				break;
 			case 6000:
-				conf |= BYT_DEBOUNCE_PULSE_6MS;
+				debounce |= BYT_DEBOUNCE_PULSE_6MS;
 				break;
 			case 12000:
-				conf |= BYT_DEBOUNCE_PULSE_12MS;
+				debounce |= BYT_DEBOUNCE_PULSE_12MS;
 				break;
 			case 24000:
-				conf |= BYT_DEBOUNCE_PULSE_24MS;
+				debounce |= BYT_DEBOUNCE_PULSE_24MS;
 				break;
 			default:
 				ret = -EINVAL;
 			}
 
+			if (!ret)
+				writel(debounce, db_reg);
 			break;
 		default:
 			ret = -ENOTSUPP;