[PATCH] iio: gyro: mpu3050: Fix runtime PM refcount leak in trigger enable path

[laixiangwu]

mpu3050_drdy_trigger_set_state() calls pm_runtime_get_sync() when
enabling the data ready trigger, but all five error returns in the
enable path return directly without the matching
pm_runtime_put_autosuspend(). The disable path, in contrast, drops
the reference correctly.

As a result, a failed trigger enable leaves the runtime PM usage
counter incremented and the sensor can never runtime suspend. It also
leaves hw_irq_trigger set to true, claiming the hardware IRQ is in
use when it is not.

Add an error label that drops the runtime PM reference and clears
hw_irq_trigger, and check the return value of pm_runtime_get_sync()
like the rest of the driver does.

Fixes: 3904b28efb2c ("iio: gyro: Add driver for the MPU-3050 gyroscope")
Signed-off-by: laixiangwu <laixiangwu@xxxxxxxxxxxxxxxxxxxx>
---
 drivers/iio/gyro/mpu3050-core.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/gyro/mpu3050-core.c b/drivers/iio/gyro/mpu3050-core.c
index 07c0f9011..9c6d5ba82 100644
--- a/drivers/iio/gyro/mpu3050-core.c
+++ b/drivers/iio/gyro/mpu3050-core.c
@@ -988,20 +988,24 @@ static int mpu3050_drdy_trigger_set_state(struct iio_trigger *trig,
 		return 0;
 	} else {
 		/* Else we're enabling the trigger from this point */
-		pm_runtime_get_sync(mpu3050->dev);
+		ret = pm_runtime_get_sync(mpu3050->dev);
+		if (ret < 0) {
+			pm_runtime_put_noidle(mpu3050->dev);
+			return ret;
+		}
 		mpu3050->hw_irq_trigger = true;
 
 		/* Disable all things in the FIFO */
 		ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0);
 		if (ret)
-			return ret;
+			goto err_put_pm;
 
 		/* Reset and enable the FIFO */
 		ret = regmap_set_bits(mpu3050->map, MPU3050_USR_CTRL,
 				      MPU3050_USR_CTRL_FIFO_EN |
 				      MPU3050_USR_CTRL_FIFO_RST);
 		if (ret)
-			return ret;
+			goto err_put_pm;
 
 		mpu3050->pending_fifo_footer = false;
 
@@ -1013,12 +1017,12 @@ static int mpu3050_drdy_trigger_set_state(struct iio_trigger *trig,
 				   MPU3050_FIFO_EN_GYRO_ZOUT |
 				   MPU3050_FIFO_EN_FOOTER);
 		if (ret)
-			return ret;
+			goto err_put_pm;
 
 		/* Configure the sample engine */
 		ret = mpu3050_start_sampling(mpu3050);
 		if (ret)
-			return ret;
+			goto err_put_pm;
 
 		/* Clear IRQ flag */
 		ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
@@ -1037,10 +1041,16 @@ static int mpu3050_drdy_trigger_set_state(struct iio_trigger *trig,
 
 		ret = regmap_write(mpu3050->map, MPU3050_INT_CFG, val);
 		if (ret)
-			return ret;
+			goto err_put_pm;
 	}
 
 	return 0;
+
+err_put_pm:
+	pm_runtime_put_autosuspend(mpu3050->dev);
+	mpu3050->hw_irq_trigger = false;
+
+	return ret;
 }
 
 static const struct iio_trigger_ops mpu3050_trigger_ops = {
-- 
2.50.1.windows.1