From 7bc9f038d02c2fc14e53e4aaca651deaf6d0de3f Mon Sep 17 00:00:00 2001 From: Jacob Chen Date: Sun, 1 Oct 2017 12:22:37 +0200 Subject: media: i2c: OV5647: ensure clock lane in LP-11 state before streaming on When I was supporting Rpi Camera Module on the ASUS Tinker board, I found this driver have some issues with rockchip's mipi-csi driver. It didn't place clock lane in LP-11 state before performing D-PHY initialisation. >From our experience, on some OV sensors, LP-11 state is not achieved while BIT(5)-0x4800 is cleared. So let's set BIT(5) and BIT(0) both while not streaming, in order to coax the clock lane into LP-11 state. 0x4800 : MIPI CTRL 00 BIT(5) : clock lane gate enable 0: continuous 1: none-continuous BIT(0) : manually set clock lane 0: Not used 1: used Signed-off-by: Jacob Chen Reviewed-by: Luis Oliveira Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/ov5647.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'drivers/media/i2c/ov5647.c') diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c index 95ce90fdb876..247302d01f53 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 +328,10 @@ static int __sensor_init(struct v4l2_subdev *sd) return ret; } - return ov5647_write(sd, 0x4800, 0x04); + /* + * stream off to make the clock lane into LP-11 state. + */ + return ov5647_stream_off(sd); } static int ov5647_sensor_power(struct v4l2_subdev *sd, int on) -- cgit v1.2.3-55-g7522