Hi Prabhakar,
I'm currently testing the OV5640 CCIR656 embedded synchronisation mode
on STM32MP1 running STM32 DCMI camera interface.
Tests not yet fully completed but sounds good, more details below.
On 8/3/20 4:31 PM, Lad Prabhakar wrote:
> Enable support for BT656 mode.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> Reviewed-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> ---
> drivers/media/i2c/ov5640.c | 40 +++++++++++++++++++++++++++-----------
> 1 file changed, 29 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> index ec444bee2ce9..08c67250042f 100644
> --- a/drivers/media/i2c/ov5640.c
> +++ b/drivers/media/i2c/ov5640.c
> @@ -82,6 +82,7 @@
> #define OV5640_REG_VFIFO_HSIZE 0x4602
> #define OV5640_REG_VFIFO_VSIZE 0x4604
> #define OV5640_REG_JPG_MODE_SELECT 0x4713
> +#define OV5640_REG_CCIR656_CTRL00 0x4730
> #define OV5640_REG_POLARITY_CTRL00 0x4740
> #define OV5640_REG_MIPI_CTRL00 0x4800
> #define OV5640_REG_DEBUG_MODE 0x4814
> @@ -1216,6 +1217,18 @@ static int ov5640_set_autogain(struct ov5640_dev *sensor, bool on)
> BIT(1), on ? 0 : BIT(1));
> }
>
> +static int ov5640_set_stream_bt656(struct ov5640_dev *sensor, bool on)
> +{
> + int ret;
> +
> + ret = ov5640_write_reg(sensor, OV5640_REG_CCIR656_CTRL00, on ? 0x1 : 0x00);
> + if (ret)
> + return ret;
Please add a comment explaining bit fields from datasheet:
Bit[7]: SYNC code selection
0: Automatically generate SYNC code
1: SYNC code from register setting 0x4732~4735
Bit[4:3]: Blank toggle data options
00: Toggle data is 1'h040/1'h200
Bit[1]: Clip data disable (so clip is enabled)
Bit[0]: CCIR656 mode enable
So 0x1 stands for CCIR656 with automatic SYNC codes: SAV/EAV with
default values ie SAV=0xFF000080 & EAV=0xFF00009d.
On STM32 platform, this correspond to DCMI configuration ESCR=0xff9d80ff
and ESUR=0xffffffff.
On Renesas platform, I have not seen any configuration in code, this
SAV/EAV mode seems to be handled by default by hardware, do you confirm ?
Note that another CCIR656 embedded synchro mode could be used with
custom synchro codes FS/FE/LS/LE in registers 0x4732-0x4735, this
mode is enabled with CCIR656_CTRL00(0x4730) set to 0x81:
Bit[7]: SYNC code selection
1: SYNC code from register setting 0x4732~4735
> +
> + return ov5640_write_reg(sensor, OV5640_REG_SYS_CTRL0, on ?
> + OV5640_SOFTWARE_WAKEUP : OV5640_SOFTWARE_PWDN);
> +}
> +
> static int ov5640_set_stream_dvp(struct ov5640_dev *sensor, bool on)
> {
> return ov5640_write_reg(sensor, OV5640_REG_SYS_CTRL0, on ?
> @@ -2022,18 +2035,20 @@ static int ov5640_set_dvp(struct ov5640_dev *sensor, bool on)
> * datasheet and hardware, 0 is active high
> * and 1 is active low...)
> */
> - if (flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
> - pclk_pol = 1;
> - if (flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH)
> - hsync_pol = 1;
> - if (flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
> - vsync_pol = 1;
> + if (sensor->ep.bus_type == V4L2_MBUS_PARALLEL) {
> + if (flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
> + pclk_pol = 1;
> + if (flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH)
> + hsync_pol = 1;
> + if (flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
> + vsync_pol = 1;
>
> - ret = ov5640_write_reg(sensor, OV5640_REG_POLARITY_CTRL00,
> - (pclk_pol << 5) | (hsync_pol << 1) | vsync_pol);
> + ret = ov5640_write_reg(sensor, OV5640_REG_POLARITY_CTRL00,
> + (pclk_pol << 5) | (hsync_pol << 1) | vsync_pol);
>
> - if (ret)
> - return ret;
> + if (ret)
> + return ret;
> + }
>
> /*
> * powerdown MIPI TX/RX PHY & disable MIPI
> @@ -2057,7 +2072,8 @@ static int ov5640_set_dvp(struct ov5640_dev *sensor, bool on)
> * - 4: PCLK output enable
> * - [3:0]: D[9:6] output enable
> */
> - ret = ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT_ENABLE01, 0x7f);
> + ret = ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT_ENABLE01,
> + sensor->ep.bus_type == V4L2_MBUS_PARALLEL ? 0x7f : 0x1f);
> if (ret)
> return ret;
>
> @@ -2911,6 +2927,8 @@ static int ov5640_s_stream(struct v4l2_subdev *sd, int enable)
>
> if (sensor->ep.bus_type == V4L2_MBUS_CSI2_DPHY)
> ret = ov5640_set_stream_mipi(sensor, enable);
> + else if (sensor->ep.bus_type == V4L2_MBUS_BT656)
> + ret = ov5640_set_stream_bt656(sensor, enable);
> else
> ret = ov5640_set_stream_dvp(sensor, enable);
>
>
BR, Hugues.
