[Linux-stm32] [PATCH v3] media: ov5640: fix support of BT656 bus mode
Jacopo Mondi
jacopo at jmondi.org
Tue Oct 13 12:56:52 UTC 2020
Hi Hugues
On Tue, Oct 13, 2020 at 12:44:10PM +0000, Hugues FRUCHET wrote:
> Hi Jacopo,
>
> On 10/13/20 2:01 PM, Jacopo Mondi wrote:
> > Hi Hugues,
> >
> > On Tue, Oct 13, 2020 at 11:02:23AM +0200, Hugues Fruchet wrote:
> >> Fix PCLK polarity not being taken into account.
> >> Add comments about BT656 register control.
> >> Remove useless ov5640_set_stream_bt656() function.
> >> Refine comments about MIPI IO register control.
> >>
> >> Fixes: 4039b03720f7 ("media: i2c: ov5640: Add support for BT656 mode")
> >> Signed-off-by: Hugues Fruchet <hugues.fruchet at st.com>
> >> ---
> >> version 3:
> >> - reformat code as per Jacopo's comments
> >> version 2:
> >> - keep reset to default without error check at power off
> >>
> >> drivers/media/i2c/ov5640.c | 82 +++++++++++++++++++++++++---------------------
> >> 1 file changed, 45 insertions(+), 37 deletions(-)
> >>
> >> diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> >> index 8d0254d..8f0812e 100644
> >> --- a/drivers/media/i2c/ov5640.c
> >> +++ b/drivers/media/i2c/ov5640.c
> >> @@ -1216,20 +1216,6 @@ 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;
> >> -
> >> - return ov5640_write_reg(sensor, OV5640_REG_SYS_CTRL0, on ?
> >> - OV5640_REG_SYS_CTRL0_SW_PWUP :
> >> - OV5640_REG_SYS_CTRL0_SW_PWDN);
> >> -}
> >> -
> >> static int ov5640_set_stream_dvp(struct ov5640_dev *sensor, bool on)
> >> {
> >> return ov5640_write_reg(sensor, OV5640_REG_SYS_CTRL0, on ?
> >> @@ -1994,13 +1980,13 @@ static int ov5640_set_power_mipi(struct ov5640_dev *sensor, bool on)
> >> static int ov5640_set_power_dvp(struct ov5640_dev *sensor, bool on)
> >> {
> >> unsigned int flags = sensor->ep.bus.parallel.flags;
> >> - u8 pclk_pol = 0;
> >> - u8 hsync_pol = 0;
> >> - u8 vsync_pol = 0;
> >> + bool bt656 = sensor->ep.bus_type == V4L2_MBUS_BT656;
> >> + u8 polarities = 0;
> >> int ret;
> >>
> >> if (!on) {
> >> /* Reset settings to their default values. */
> >> + ov5640_write_reg(sensor, OV5640_REG_CCIR656_CTRL00, 0x00);
> >> ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00, 0x58);
> >> ov5640_write_reg(sensor, OV5640_REG_POLARITY_CTRL00, 0x20);
> >> ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT_ENABLE01, 0x00);
> >> @@ -2024,7 +2010,35 @@ static int ov5640_set_power_dvp(struct ov5640_dev *sensor, bool on)
> >> * - VSYNC: active high
> >> * - HREF: active low
> >> * - PCLK: active low
> >> + *
> >> + * VSYNC & HREF are not configured if BT656 bus mode is selected
> >> */
> >> +
> >> + /*
> >> + * BT656 embedded synchronization configuration
> >> + *
> >> + * CCIR656 CTRL00
> >> + * - [7]: SYNC code selection (0: auto generate sync code,
> >> + * 1: sync code from regs 0x4732-0x4735)
> >> + * - [6]: f value in CCIR656 SYNC code when fixed f value
> >> + * - [5]: Fixed f value
> >> + * - [4:3]: Blank toggle data options (00: data=1'h040/1'h200,
> >> + * 01: data from regs 0x4736-0x4738, 10: always keep 0)
> >> + * - [1]: Clip data disable
> >> + * - [0]: CCIR656 mode enable
> >> + *
> >> + * Default CCIR656 SAV/EAV mode with default codes
> >> + * SAV=0xff000080 & EAV=0xff00009d is enabled here with settings:
> >> + * - CCIR656 mode enable
> >> + * - auto generation of sync codes
> >> + * - blank toggle data 1'h040/1'h200
> >> + * - clip reserved data (0x00 & 0xff changed to 0x01 & 0xfe)
> >> + */
> >> + ret = ov5640_write_reg(sensor, OV5640_REG_CCIR656_CTRL00,
> >> + bt656 ? 0x01 : 0x00);
> >> + if (ret)
> >> + return ret;
> >> +
> >> /*
> >> * configure parallel port control lines polarity
> >> *
> >> @@ -2035,29 +2049,26 @@ static int ov5640_set_power_dvp(struct ov5640_dev *sensor, bool on)
> >> * datasheet and hardware, 0 is active high
> >> * and 1 is active low...)
> >> */
> >> - if (sensor->ep.bus_type == V4L2_MBUS_PARALLEL) {
> >> - if (flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
> >> - pclk_pol = 1;
> >> + if (!bt656) {
> >> if (flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH)
> >> - hsync_pol = 1;
> >> + polarities |= BIT(1);
> >> if (flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
> >> - vsync_pol = 1;
> >
> > Ups, this doesn't match what's reported in the manual version I have
> > (version 2.03, page 134) I read:
> >
> > VSYNC polarity 0: Active low
> > 1: Active high
> >
> > Was this a bug already present in the code ? >
> > Anyway, this has not been introduced by this patch, but might be a
> > good occasion to fix it.
>
> Code is good, this is a "manual bug" that was documented by me when
> submitting DVP support few lines above ;):
> * - [0]: VSYNC polarity (mismatch here between
> * datasheet and hardware, 0 is active high
> * and 1 is active low...)
Ups, missed that as it was not in the patch :D
Thanks for the clarification!
>
> >
> > Reviewed-by: Jacopo Mondi <jacopo at jmondi.org>
> >
> > Thanks
> > j
> >
> >> -
> >> - ret = ov5640_write_reg(sensor, OV5640_REG_POLARITY_CTRL00,
> >> - (pclk_pol << 5) | (hsync_pol << 1) |
> >> - vsync_pol);
> >> -
> >> - if (ret)
> >> - return ret;
> >> + polarities |= BIT(0);
> >> }
> >> + if (flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
> >> + polarities |= BIT(5);
> >> +
> >> + ret = ov5640_write_reg(sensor, OV5640_REG_POLARITY_CTRL00, polarities);
> >> + if (ret)
> >> + return ret;
> >>
> >> /*
> >> - * powerdown MIPI TX/RX PHY & disable MIPI
> >> + * powerdown MIPI TX/RX PHY & enable DVP
> >> *
> >> * MIPI CONTROL 00
> >> - * 4: PWDN PHY TX
> >> - * 3: PWDN PHY RX
> >> - * 2: MIPI enable
> >> + * [4] = 1 : Power down MIPI HS Tx
> >> + * [3] = 1 : Power down MIPI LS Rx
> >> + * [2] = 0 : DVP enable (MIPI disable)
> >> */
> >> ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00, 0x18);
> >> if (ret)
> >> @@ -2074,8 +2085,7 @@ static int ov5640_set_power_dvp(struct ov5640_dev *sensor, bool on)
> >> * - [3:0]: D[9:6] output enable
> >> */
> >> ret = ov5640_write_reg(sensor, OV5640_REG_PAD_OUTPUT_ENABLE01,
> >> - sensor->ep.bus_type == V4L2_MBUS_PARALLEL ?
> >> - 0x7f : 0x1f);
> >> + bt656 ? 0x1f : 0x7f);
> >> if (ret)
> >> return ret;
> >>
> >> @@ -2925,8 +2935,6 @@ 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);
> >>
> >> --
> >> 2.7.4
> >>
>
> BR,
> Hugues.
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