iio: gyro: fxas21002c: Fix missing data update in trigger handler

BugLink: https://bugs.launchpad.net/bugs/2097298

commit fa13ac6 upstream.

The fxas21002c_trigger_handler() may fail to acquire sample data because
the runtime PM enters the autosuspend state and sensor can not return
sample data in standby mode..

Resume the sensor before reading the sample data into the buffer within the
trigger handler. After the data is read, place the sensor back into the
autosuspend state.

Fixes: a0701b6 ("iio: gyro: add core driver for fxas21002c")
Signed-off-by: Carlos Song <[email protected]>
Signed-off-by: Frank Li <[email protected]>
Link: https://patch.msgid.link/[email protected]
Cc: <[email protected]>
Signed-off-by: Jonathan Cameron <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Noah Wager <[email protected]>
Signed-off-by: Koichiro Den <[email protected]>

Author: NXP-CarlosSong

drivers/iio/gyro/fxas21002c_core.c

@@ -730,14 +730,21 @@ static irqreturn_t fxas21002c_trigger_handler(int irq, void *p)
 	int ret;
 
 	mutex_lock(&data->lock);
+	ret = fxas21002c_pm_get(data);
+	if (ret < 0)
+		goto out_unlock;
+
 	ret = regmap_bulk_read(data->regmap, FXAS21002C_REG_OUT_X_MSB,
 			       data->buffer, CHANNEL_SCAN_MAX * sizeof(s16));
 	if (ret < 0)
-		goto out_unlock;
+		goto out_pm_put;
 
 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
 					   data->timestamp);
 
+out_pm_put:
+	fxas21002c_pm_put(data);
+
 out_unlock:
 	mutex_unlock(&data->lock);