Hi all, 2017-07-25 10:34 GMT+08:00 Jacob Chen <jacob-chen@xxxxxxxxxx>: > According to datasheet, BIT5 in reg-0x4800 are used to > enable/disable clock lane gate. > > It's wrong to make clock lane free running before > sensor stream on was called, while the mipi phy > are not initialized. > > Signed-off-by: Jacob Chen <jacob-chen@xxxxxxxxxx> > --- > drivers/media/i2c/ov5647.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c > index 95ce90f..d3e6fd0 100644 > --- a/drivers/media/i2c/ov5647.c > +++ b/drivers/media/i2c/ov5647.c > @@ -253,6 +253,10 @@ static int ov5647_stream_on(struct v4l2_subdev *sd) > { > int ret; > > + ret = ov5647_write(sd, 0x4800, 0x04); > + if (ret < 0) > + return ret; > + > ret = ov5647_write(sd, 0x4202, 0x00); > if (ret < 0) > return ret; > @@ -264,6 +268,10 @@ static int ov5647_stream_off(struct v4l2_subdev *sd) > { > int ret; > > + ret = ov5647_write(sd, 0x4800, 0x25); > + if (ret < 0) > + return ret; > + > ret = ov5647_write(sd, 0x4202, 0x0f); > if (ret < 0) > return ret; > @@ -320,7 +328,7 @@ static int __sensor_init(struct v4l2_subdev *sd) > return ret; > } > > - return ov5647_write(sd, 0x4800, 0x04); > + return ov5647_stream_off(sd); > } > > static int ov5647_sensor_power(struct v4l2_subdev *sd, int on) > -- > 2.7.4 > Can anyone comment on it? I saw there is a same discussion in https://patchwork.kernel.org/patch/9569031/ There is a comment in i.MX CSI2 driver. " Configure MIPI Camera Sensor to put all Tx lanes in LP-11 state. This must be carried out by the MIPI sensor's s_power(ON) subdev op. " That's what this patch do, sensor driver should make sure that clock lanes are in stop state while not streaming.