[Linux-stm32] [PATCH v2] media: ov5640: fix support of BT656 bus mode
Lad, Prabhakar
prabhakar.csengg at gmail.com
Wed Oct 14 13:24:54 UTC 2020
Hi Hugues,
On Wed, Oct 14, 2020 at 11:43 AM Hugues FRUCHET <hugues.fruchet at st.com> wrote:
>
> Hi Prabhakar,
>
> On 10/14/20 12:26 AM, Lad, Prabhakar wrote:
> > Hi Hugues,
> >
> > Thank you for catching the polarity bug.
> Y're welcome.
>
> >
> > On Mon, Oct 12, 2020 at 3:55 PM Hugues Fruchet <hugues.fruchet at st.com> 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>
> >> ---
> >> drivers/media/i2c/ov5640.c | 77 +++++++++++++++++++++++++++-------------------
> >> 1 file changed, 45 insertions(+), 32 deletions(-)
> >>
> >> diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> >> index 8d0254d..c0ebf4c 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 ?
> >> @@ -1994,6 +1980,7 @@ 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;
> >> + bool bt656 = sensor->ep.bus_type == V4L2_MBUS_BT656;
> >> u8 pclk_pol = 0;
> >> u8 hsync_pol = 0;
> >> u8 vsync_pol = 0;
> >> @@ -2001,6 +1988,7 @@ static int ov5640_set_power_dvp(struct ov5640_dev *sensor, bool on)
> >>
> >> 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);
> >> @@ -2024,23 +2012,51 @@ 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
> >> */
> >> +
> >> /*
> >> - * configure parallel port control lines polarity
> >> + * BT656 embedded synchronization configuration
> >> *
> >> - * POLARITY CTRL0
> >> - * - [5]: PCLK polarity (0: active low, 1: active high)
> >> - * - [1]: HREF polarity (0: active low, 1: active high)
> >> - * - [0]: VSYNC polarity (mismatch here between
> >> - * datasheet and hardware, 0 is active high
> >> - * and 1 is active low...)
> >> + * 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)
> >> */
> >> - if (sensor->ep.bus_type == V4L2_MBUS_PARALLEL) {
> >> + ret = ov5640_write_reg(sensor, OV5640_REG_CCIR656_CTRL00,
> >> + bt656 ? 0x01 : 0x00);
> > Did you test bt656 on your platform ? with these changes BT.656 mode
> > doesn't work anymore on my platform. With the below diff on top of
> > your patch it works OK. Could you please test the same works on your
> > platform.
>
> Yes of course, tested on STM32MP1 evaluation board with OV5640/parallel
> setup (stm32-dcmi capture driver). Several captures made, no issues.
>
> So in short you have to move the CCIR656 mode enable from set_power() to
> set_stream(), this is similar to changes you've made in code recently
> around OV5640_REG_SYS_CTRL0 & SW_PWUP/DOWN, but the reason to do that is
> still not understood, at least on my side.
> My understanding reading your patch was that OV5640_REG_SYS_CTRL0 ->
> SW_PWUP trigs the real "stream on" of the sensor and only at that time
> the data are produced by sensor, but if this is true, why do we need to
> enable CCIR656 right before SW_PWUP instead of enabling it with other
> DVP settings (DVP enable and so on...) ? This is not logical.
>
Sorry my bad it was one of thing, Ive done some thorough re-testing
with just your patch and it looks OK.
Cheers,
Prabhakar
> I think that we have to understand what happens on your side before
> going to more changes on this already so complex driver.
>
> >
> > diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> > index 49e73ace8685..c5e45bc17bdf 100644
> > --- a/drivers/media/i2c/ov5640.c
> > +++ b/drivers/media/i2c/ov5640.c
> > @@ -1977,6 +1977,40 @@ static int ov5640_set_power_mipi(struct
> > ov5640_dev *sensor, bool on)
> > return 0;
> > }
> >
> > +static int ov5640_set_stream_bt656(struct ov5640_dev *sensor, bool on)
> > +{
> > + int ret;
> > +
> > + /*
> > + * 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,
> > + 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_power_dvp(struct ov5640_dev *sensor, bool on)
> > {
> > unsigned int flags = sensor->ep.bus.parallel.flags;
> > @@ -2014,31 +2048,6 @@ static int ov5640_set_power_dvp(struct
> > ov5640_dev *sensor, bool on)
> > * 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
> > *
> > @@ -2935,6 +2944,8 @@ 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);
> >
> > Cheers,
> > Prabhakar
> >
> >> + if (ret)
> >> + return ret;
> >> +
> >> + if (on) {
> >> + /*
> >> + * configure parallel port control lines polarity
> >> + *
> >> + * POLARITY CTRL0
> >> + * - [5]: PCLK polarity (0: active low, 1: active high)
> >> + * - [1]: HREF polarity (0: active low, 1: active high)
> >> + * - [0]: VSYNC polarity (mismatch here between
> >> + * 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)
> >> + if (!bt656 && flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH)
> >> hsync_pol = 1;
> >> - if (flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
> >> + if (!bt656 && flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
> >> vsync_pol = 1;
> >>
> >> ret = ov5640_write_reg(sensor, OV5640_REG_POLARITY_CTRL00,
> >> @@ -2052,12 +2068,12 @@ static int ov5640_set_power_dvp(struct ov5640_dev *sensor, bool on)
> >> }
> >>
> >> /*
> >> - * 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 +2090,7 @@ 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 +2940,6 @@ 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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