The sensor may be powered by either one of its sub-devices being accessed from the user space (an open file handle) or by its s_power() op being called with non-zero on argument. The driver counts the users and if any reason to keep the device powered exists it will be powered. However, a faulty condition was used in recognising the need to power off the sensor, leading it to be powered off every time any of its uses went away. Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> --- drivers/media/i2c/smiapp/smiapp-core.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) diff --git a/drivers/media/i2c/smiapp/smiapp-core.c b/drivers/media/i2c/smiapp/smiapp-core.c index 94ae3a3..a9c6f9b 100644 --- a/drivers/media/i2c/smiapp/smiapp-core.c +++ b/drivers/media/i2c/smiapp/smiapp-core.c @@ -1400,19 +1400,12 @@ static int smiapp_set_power(struct v4l2_subdev *subdev, int on) mutex_lock(&sensor->power_mutex); - /* - * If the power count is modified from 0 to != 0 or from != 0 - * to 0, update the power state. - */ - if (!sensor->power_count == !on) - goto out; - - if (on) { + if (on && !sensor->power_count) { /* Power on and perform initialisation. */ ret = smiapp_power_on(sensor); if (ret < 0) goto out; - } else { + } else if (!on && sensor->power_count == 1) { smiapp_power_off(sensor); } -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html