[PATCH v3 08/11] hwmon: chipcap2: balance regulator state

[Javier Carrasco <javier.carrasco.cruz@gmail.com>]

The current implementation does not guarantee that the calls to
regulator_enable() and regulator_disable() are balanced.
regulator_is_enabled() might return a negative value, and an always-on
attribute in the DT might break the symmetry anyway.

Add a regulator_enabled flag to keep balance within this regulator
consumer.

Fixes: 3af350929e75 ("hwmon: Add support for Amphenol ChipCap 2")
Cc: stable@vger.kernel.org
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
 drivers/hwmon/chipcap2.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/hwmon/chipcap2.c b/drivers/hwmon/chipcap2.c
index 837b1830f2e4..952789fdb9db 100644
--- a/drivers/hwmon/chipcap2.c
+++ b/drivers/hwmon/chipcap2.c
@@ -91,6 +91,7 @@ struct cc2_data {
 	int irq_low;
 	int irq_high;
 	bool process_irqs;
+	bool regulator_enabled;
 };
 
 /* %RH as a per cent mille from a register value */
@@ -120,7 +121,7 @@ static int cc2_enable(struct cc2_data *data)
 	int ret;
 
 	/* exclusive regulator, check in case a disable failed */
-	if (regulator_is_enabled(data->regulator)) {
+	if (data->regulator_enabled) {
 		data->process_irqs = true;
 		return 0;
 	}
@@ -132,6 +133,8 @@ static int cc2_enable(struct cc2_data *data)
 	if (ret < 0)
 		return ret;
 
+	data->regulator_enabled = true;
+
 	usleep_range(CC2_STARTUP_TIME_US, CC2_STARTUP_TIME_US + 125);
 
 	data->process_irqs = true;
@@ -147,11 +150,16 @@ static void cc2_disable(struct cc2_data *data)
 	data->process_irqs = false;
 
 	/* exclusive regulator, check in case an enable failed */
-	if (regulator_is_enabled(data->regulator)) {
-		err = regulator_disable(data->regulator);
-		if (err)
-			dev_dbg(&data->client->dev, "Failed to disable device");
+	if (!data->regulator_enabled)
+		return;
+
+	err = regulator_disable(data->regulator);
+	if (err) {
+		dev_dbg(&data->client->dev, "Failed to disable device");
+		return;
 	}
+
+	data->regulator_enabled = false;
 }
 
 static void cc2_disable_action(void *data)

-- 
2.43.0