Hi Jacopo, Thank you for the patch. On Mon, Apr 12, 2021 at 11:34:44AM +0200, Jacopo Mondi wrote: > The current RDACM21 initialization routine powers up the OV10640 image > sensor after the OV490 ISP. The ISP is programmed with a firmare loaded > from an embedded serial flash that (most probably) tries to interact and > program also the image sensor connected to the ISP. > > As described in commit ("media: i2c: rdacm21: Fix OV10640 powerup") the s/[()]//g > image sensor powerdown signal is kept high by an internal pull up > resistor and occasionally fails to startup correctly if the powerdown > line is not asserted explicitely. Failures in the OV10640 startup causes > the OV490 firmware to fail to boot correctly resulting in the camera > module initialization to fail consequentially. > > Fix this by powering up the OV10640 image sensor before testing the > OV490 firmware boot completion, by splitting the ov10640_initialize() > function in an ov10640_power_up() one and an ov10640_check_id() one. > > Also make sure the OV10640 identification procedure gives enough time to > the image sensor to resume after the programming phase performed by the > OV490 firmware by repeating the ID read procedure. > > This commit fixes a sporadic start-up error triggered by a failure to > detect the OV490 firmware boot completion: > rdacm21 8-0054: Timeout waiting for firmware boot > > Fixes: a59f853b3b4b ("media: i2c: Add driver for RDACM21 camera module") > Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > --- > drivers/media/i2c/rdacm21.c | 46 ++++++++++++++++++++++++++----------- > 1 file changed, 32 insertions(+), 14 deletions(-) > > diff --git a/drivers/media/i2c/rdacm21.c b/drivers/media/i2c/rdacm21.c > index 7c0a4a84340a..43c41cb800a4 100644 > --- a/drivers/media/i2c/rdacm21.c > +++ b/drivers/media/i2c/rdacm21.c > @@ -69,6 +69,7 @@ > #define OV490_ISP_VSIZE_LOW 0x80820062 > #define OV490_ISP_VSIZE_HIGH 0x80820063 > > +#define OV10640_PID_TIMEOUT 20 > #define OV10640_ID_HIGH 0xa6 > #define OV10640_CHIP_ID 0x300a > #define OV10640_PIXEL_RATE 55000000 > @@ -329,10 +330,8 @@ static const struct v4l2_subdev_ops rdacm21_subdev_ops = { > .pad = &rdacm21_subdev_pad_ops, > }; > > -static int ov10640_initialize(struct rdacm21_device *dev) > +static void ov10640_power_up(struct rdacm21_device *dev) > { > - u8 val; > - > /* Enable GPIO0#0 (reset) and GPIO1#0 (pwdn) as output lines. */ > ov490_write_reg(dev, OV490_GPIO_SEL0, OV490_GPIO0); > ov490_write_reg(dev, OV490_GPIO_SEL1, OV490_SPWDN0); > @@ -347,18 +346,35 @@ static int ov10640_initialize(struct rdacm21_device *dev) > usleep_range(1500, 3000); > ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE0, OV490_GPIO0); > usleep_range(3000, 5000); > +} > > - /* Read OV10640 ID to test communications. */ > - ov490_write_reg(dev, OV490_SCCB_SLAVE0_DIR, OV490_SCCB_SLAVE_READ); > - ov490_write_reg(dev, OV490_SCCB_SLAVE0_ADDR_HIGH, OV10640_CHIP_ID >> 8); > - ov490_write_reg(dev, OV490_SCCB_SLAVE0_ADDR_LOW, OV10640_CHIP_ID & 0xff); > - > - /* Trigger SCCB slave transaction and give it some time to complete. */ > - ov490_write_reg(dev, OV490_HOST_CMD, OV490_HOST_CMD_TRIGGER); > - usleep_range(1000, 1500); > +static int ov10640_check_id(struct rdacm21_device *dev) > +{ > + unsigned int i; > + u8 val; > > - ov490_read_reg(dev, OV490_SCCB_SLAVE0_DIR, &val); > - if (val != OV10640_ID_HIGH) { > + /* Read OV10640 ID to test communications. */ > + for (i = 0; i < OV10640_PID_TIMEOUT; ++i) { > + ov490_write_reg(dev, OV490_SCCB_SLAVE0_DIR, > + OV490_SCCB_SLAVE_READ); > + ov490_write_reg(dev, OV490_SCCB_SLAVE0_ADDR_HIGH, > + OV10640_CHIP_ID >> 8); > + ov490_write_reg(dev, OV490_SCCB_SLAVE0_ADDR_LOW, > + OV10640_CHIP_ID & 0xff); > + > + /* > + * Trigger SCCB slave transaction and give it some time > + * to complete. > + */ > + ov490_write_reg(dev, OV490_HOST_CMD, OV490_HOST_CMD_TRIGGER); > + usleep_range(1000, 1500); > + > + ov490_read_reg(dev, OV490_SCCB_SLAVE0_DIR, &val); > + if (val == OV10640_ID_HIGH) > + break; > + usleep_range(1000, 1500); > + } > + if (i == OV10640_PID_TIMEOUT) { > dev_err(dev->dev, "OV10640 ID mismatch: (0x%02x)\n", val); > return -ENODEV; > } > @@ -374,6 +390,8 @@ static int ov490_initialize(struct rdacm21_device *dev) > unsigned int i; > int ret; > > + ov10640_power_up(dev); > + > /* > * Read OV490 Id to test communications. Give it up to 40msec to > * exit from reset. > @@ -411,7 +429,7 @@ static int ov490_initialize(struct rdacm21_device *dev) > return -ENODEV; > } > > - ret = ov10640_initialize(dev); > + ret = ov10640_check_id(dev); > if (ret) > return ret; > -- Regards, Laurent Pinchart