From 0fec1c81707f5335d0b04b5e97d2ddd0b902377b Mon Sep 17 00:00:00 2001 From: Lad Prabhakar Date: Tue, 10 Mar 2020 14:17:07 +0100 Subject: [PATCH] media: i2c: imx219: Fix power sequence Commit ca45448a56659c6df6e0436188e97f6cc65dea8a upstream. When supporting Rpi Camera v2 Module on the RZ/G2E, found the driver had some issues with rcar mipi-csi driver. The sensor never entered into LP-11 state. The powerup sequence in the datasheet[1] shows the sensor entering into LP-11 in streaming mode, so to fix this issue transitions are performed from "streaming -> standby" in the probe() after power up. With this commit the sensor is able to enter LP-11 mode during power up, as expected by some CSI-2 controllers. [1] https://publiclab.org/system/images/photos/000/023/294/original/ RASPBERRY_PI_CAMERA_V2_DATASHEET_IMX219PQH5_7.0.0_Datasheet_XXX.PDF Signed-off-by: Lad Prabhakar Acked-by: Dave Stevenson Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/imx219.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) --- a/drivers/media/i2c/imx219.c +++ b/drivers/media/i2c/imx219.c @@ -1224,6 +1224,23 @@ static int imx219_probe(struct i2c_clien /* Set default mode to max resolution */ imx219->mode = &supported_modes[0]; + /* sensor doesn't enter LP-11 state upon power up until and unless + * streaming is started, so upon power up switch the modes to: + * streaming -> standby + */ + ret = imx219_write_reg(imx219, IMX219_REG_MODE_SELECT, + IMX219_REG_VALUE_08BIT, IMX219_MODE_STREAMING); + if (ret < 0) + goto error_power_off; + usleep_range(100, 110); + + /* put sensor back to standby mode */ + ret = imx219_write_reg(imx219, IMX219_REG_MODE_SELECT, + IMX219_REG_VALUE_08BIT, IMX219_MODE_STANDBY); + if (ret < 0) + goto error_power_off; + usleep_range(100, 110); + ret = imx219_init_controls(imx219); if (ret) goto error_power_off;