Hi Jacopo, On Thu, Jan 14, 2021 at 08:52:28AM +0100, Jacopo Mondi wrote: > On Thu, Jan 14, 2021 at 01:23:25AM +0200, Laurent Pinchart wrote: > > On Wed, Jan 13, 2021 at 07:55:01PM +0100, Jacopo Mondi wrote: > > > The embedded OV490 ISP chip provides a secondary SCCB interface and > > > two GPIO lines to control the connected OV10640 image sensor. > > > > > > Break out the OV10640 initialization from the OV490 initialization and > > > explicitely control the powerdown and reset GPIOs. After the image > > > > s/explicitely/explicitly/ > > > > > sensor has been hard reset, implement a more clear handling of the > > > secondary SCCB interface to read the image sensor chip ID. > > > > > > Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx> > > > --- > > > drivers/media/i2c/rdacm21.c | 75 ++++++++++++++++++++++++++++++------- > > > 1 file changed, 61 insertions(+), 14 deletions(-) > > > > > > diff --git a/drivers/media/i2c/rdacm21.c b/drivers/media/i2c/rdacm21.c > > > index 0428e3209463..944009687de5 100644 > > > --- a/drivers/media/i2c/rdacm21.c > > > +++ b/drivers/media/i2c/rdacm21.c > > > @@ -30,11 +30,24 @@ > > > #define OV490_PAGE_HIGH_REG 0xfffd > > > #define OV490_PAGE_LOW_REG 0xfffe > > > > > > +/* > > > + * The SCCB slave handling is undocumented; the registers naming scheme is > > > + * totally arbitrary. > > > + */ > > > +#define OV490_SCCB_SLAVE_WRITE 0x00 > > > +#define OV490_SCCB_SLAVE_READ 0x01 > > > +#define OV490_SCCB_SLAVE0_DIR 0x80195000 > > > +#define OV490_SCCB_SLAVE0_ADDR_HIGH 0x80195001 > > > +#define OV490_SCCB_SLAVE0_ADDR_LOW 0x80195002 > > > + > > > #define OV490_DVP_CTRL3 0x80286009 > > > > > > #define OV490_ODS_CTRL_FRAME_OUTPUT_EN 0x0c > > > #define OV490_ODS_CTRL 0x8029d000 > > > > > > +#define OV490_HOST_CMD 0x808000c0 > > > +#define OV490_HOST_CMD_TRIGGER 0xc1 > > > + > > > #define OV490_ID_VAL 0x0490 > > > #define OV490_ID(_p, _v) ((((_p) & 0xff) << 8) | ((_v) & 0xff)) > > > #define OV490_PID 0x8080300a > > > @@ -42,12 +55,22 @@ > > > #define OV490_PID_TIMEOUT 20 > > > #define OV490_OUTPUT_EN_TIMEOUT 300 > > > > > > +#define OV490_GPIO0_RESETB 0x01 > > > > Shouldn't this be named just OV490_GPIO0 ? The fact that it's connected > > to the RESETB signal of the OV10640 is board-specific, not an OV490 > > intrinsic property. > > > > BIT(0) ? > > > > > +#define OV490_SPWDN0 0x01 > > > > Same here. > > > > Correct, I'll fix... > > > > +#define OV490_GPIO_SEL0 0x80800050 > > > +#define OV490_GPIO_SEL1 0x80800051 > > > +#define OV490_GPIO_DIRECTION0 0x80800054 > > > +#define OV490_GPIO_DIRECTION1 0x80800055 > > > +#define OV490_GPIO_OUTPUT_VALUE0 0x80800058 > > > +#define OV490_GPIO_OUTPUT_VALUE1 0x80800059 > > > + > > > #define OV490_ISP_HSIZE_LOW 0x80820060 > > > #define OV490_ISP_HSIZE_HIGH 0x80820061 > > > #define OV490_ISP_VSIZE_LOW 0x80820062 > > > #define OV490_ISP_VSIZE_HIGH 0x80820063 > > > > > > -#define OV10640_ID_LOW 0xa6 > > > +#define OV10640_ID_HIGH 0xa6 > > > +#define OV10640_CHIP_ID 0x300a > > > #define OV10640_PIXEL_RATE 55000000 > > > > > > struct rdacm21_device { > > > @@ -306,6 +329,39 @@ static const struct v4l2_subdev_ops rdacm21_subdev_ops = { > > > .pad = &rdacm21_subdev_pad_ops, > > > }; > > > > > > +static int ov10640_initialize(struct rdacm21_device *dev) > > > +{ > > > + u8 val; > > > + > > > + /* Power-up OV10640 by setting RESETB and PWDNB pins high. */ > > > + ov490_write_reg(dev, OV490_GPIO_SEL0, OV490_GPIO0_RESETB); > > > + ov490_write_reg(dev, OV490_GPIO_SEL1, OV490_SPWDN0); > > > + ov490_write_reg(dev, OV490_GPIO_DIRECTION0, OV490_GPIO0_RESETB); > > > + ov490_write_reg(dev, OV490_GPIO_DIRECTION1, OV490_SPWDN0); > > > + ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE0, OV490_GPIO0_RESETB); > > > + ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE0, OV490_SPWDN0); > > > + usleep_range(3000, 5000); > > > > So the OV490 firmware doesn't handle this ? > > Do you mean the delay or the reset of the ov10640 ? > > I need the delay here otherwise reading the ov10640 id fails below. > Same for the reset :) > > About reset, it seems it does not... The ov490 settings are loaded > from an EEPROM but I don't know what it content is, maybe it's just > about the imaging-related settings ? I meant the configuration of the GPIOs and the reset of the sensor, yes. I was just curious, as I was expecting the firmware to handle all the platform-specific data. > > > + > > > + /* 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, (u8)OV10640_CHIP_ID); > > > + > > > + /* 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) { > > > + dev_err(dev->dev, "OV10640 ID mismatch: (0x%02x)\n", val); > > > + return -ENODEV; > > > + } > > > > Would it make sense to create an ov490_sensor_read() helper ? > > While developing this I went and also tested reading other registers > of the ov10640 and I had contradictory results. I'm mostly wondering > if OV490_HOST_CMD_TRIGGER is correct in all cases, as I have some BSP > code that uses a different value. > > Can we wait for an helper until we have more users ? I don't mind. > > > + > > > + dev_dbg(dev->dev, "OV10640 ID = 0x%2x\n", val); > > > + > > > + return 0; > > > +} > > > + > > > static int ov490_initialize(struct rdacm21_device *dev) > > > { > > > u8 pid, ver, val; > > > @@ -349,20 +405,11 @@ static int ov490_initialize(struct rdacm21_device *dev) > > > return -ENODEV; > > > } > > > > > > - /* Read OV10640 Id to test communications. */ > > > - ov490_write_reg(dev, 0x80195000, 0x01); > > > - ov490_write_reg(dev, 0x80195001, 0x30); > > > - ov490_write_reg(dev, 0x80195002, 0x0a); > > > - ov490_write_reg(dev, 0x808000c0, 0xc1); > > > - > > > - ov490_read_reg(dev, 0x80195000, &val); > > > - if (val != OV10640_ID_LOW) { > > > - dev_err(dev->dev, "OV10640 ID mismatch: (0x%02x)\n", val); > > > - return -ENODEV; > > > - } > > > - > > > - dev_dbg(dev->dev, "OV10640 ID = 0x%2x\n", val); > > > + ret = ov10640_initialize(dev); > > > + if (ret) > > > + return ret; > > > > > > + /* Program OV490 with register-value table. */ > > > for (i = 0; i < ARRAY_SIZE(ov490_regs_wizard); ++i) { > > > ret = ov490_write(dev, ov490_regs_wizard[i].reg, > > > ov490_regs_wizard[i].val); -- Regards, Laurent Pinchart