From d6cb1fce4b7a46afe5124e37e805b441d776071d Mon Sep 17 00:00:00 2001
From: "Kim, Milo" <Milo.Kim@ti.com>
Date: Mon, 18 Feb 2013 06:50:48 +0000
Subject: [PATCH] --- yaml --- r: 365137 b: refs/heads/master c:
 967cfb18c0e331b43a29ae7f60ec1ef0dcb02f6b h: refs/heads/master i:   365135:
 31537d5133ed7990a034e9afddc56a54aedf9939 v: v3

---
 [refs]                         |  2 +-
 trunk/drivers/regulator/core.c | 50 ++++++++++++++++++++++++++++++----
 2 files changed, 45 insertions(+), 7 deletions(-)

diff --git a/[refs] b/[refs]
index 32aacd10d2e0..f1cf9a5831c0 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: f19b00da8ed37db4e3891fe534fcf3a605a0e562
+refs/heads/master: 967cfb18c0e331b43a29ae7f60ec1ef0dcb02f6b
diff --git a/trunk/drivers/regulator/core.c b/trunk/drivers/regulator/core.c
index 71d6adc4eeab..57d434d3145a 100644
--- a/trunk/drivers/regulator/core.c
+++ b/trunk/drivers/regulator/core.c
@@ -1529,6 +1529,42 @@ static void regulator_ena_gpio_free(struct regulator_dev *rdev)
 	}
 }
 
+/**
+ * Balance enable_count of each GPIO and actual GPIO pin control.
+ * GPIO is enabled in case of initial use. (enable_count is 0)
+ * GPIO is disabled when it is not shared any more. (enable_count <= 1)
+ */
+static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
+{
+	struct regulator_enable_gpio *pin = rdev->ena_pin;
+
+	if (!pin)
+		return -EINVAL;
+
+	if (enable) {
+		/* Enable GPIO at initial use */
+		if (pin->enable_count == 0)
+			gpio_set_value_cansleep(pin->gpio,
+						!pin->ena_gpio_invert);
+
+		pin->enable_count++;
+	} else {
+		if (pin->enable_count > 1) {
+			pin->enable_count--;
+			return 0;
+		}
+
+		/* Disable GPIO if not used */
+		if (pin->enable_count <= 1) {
+			gpio_set_value_cansleep(pin->gpio,
+						pin->ena_gpio_invert);
+			pin->enable_count = 0;
+		}
+	}
+
+	return 0;
+}
+
 static int _regulator_do_enable(struct regulator_dev *rdev)
 {
 	int ret, delay;
@@ -1544,9 +1580,10 @@ static int _regulator_do_enable(struct regulator_dev *rdev)
 
 	trace_regulator_enable(rdev_get_name(rdev));
 
-	if (rdev->ena_gpio) {
-		gpio_set_value_cansleep(rdev->ena_gpio,
-					!rdev->ena_gpio_invert);
+	if (rdev->ena_pin) {
+		ret = regulator_ena_gpio_ctrl(rdev, true);
+		if (ret < 0)
+			return ret;
 		rdev->ena_gpio_state = 1;
 	} else if (rdev->desc->ops->enable) {
 		ret = rdev->desc->ops->enable(rdev);
@@ -1648,9 +1685,10 @@ static int _regulator_do_disable(struct regulator_dev *rdev)
 
 	trace_regulator_disable(rdev_get_name(rdev));
 
-	if (rdev->ena_gpio) {
-		gpio_set_value_cansleep(rdev->ena_gpio,
-					rdev->ena_gpio_invert);
+	if (rdev->ena_pin) {
+		ret = regulator_ena_gpio_ctrl(rdev, false);
+		if (ret < 0)
+			return ret;
 		rdev->ena_gpio_state = 0;
 
 	} else if (rdev->desc->ops->disable) {