Re: [PATCH] media: i2c: ov5645: Fix CSI-2 CRC errors on RK3576 after init sequence

[Xiaolei Wang]

Hi Laurent,

Thank you so much for your review.

在 2026/9/8 18:36, Laurent Pinchart 写道:
> On Tue, Sep 08, 2026 at 01:14:32PM +0300, Sakari Ailus wrote:
> > On Wed, Aug 26, 2026 at 08:54:32AM +0000, Xiaolei Wang wrote:
> > > On the RK3576 platform, after ov5645_global_init_setting completes and
> > > before stream on, the CSI host reports a high rate of CRC errors:
> > >
> > >    MIPI_CSI2 ERR1:0x1000000 (crc,vc: 0)
> > >
> > > These errors occur exclusively in the window between init completion and
> > > stream on. Once preview starts and the sensor outputs valid HS data, no
> > > further CRC errors are observed.
> > >
> > > Commit 092e8eb90a7d ("media: i2c: ov5645: Fix power sequence") reworked
> > > the power sequence to properly enter LP-11 during power-up. As part of
> > > this change, the SYSTEM_CTRL0_STOP (0x42) write in s_power() was replaced
> > > with usleep_range(500, 1000), leaving the sensor in wake state (0x3008 =
> > > 0x02) from init through to s_stream. Reverting this commit resolves the
> > > CRC errors, confirming it as the triggering change.
> > >
> > > Restore the power-down state after init by appending { 0x3008, 0x42 } to
> > > the end of ov5645_global_init_setting[]. This powers down the sensor core
> > > after MIPI configuration is complete, while keeping the MIPI PHY active in
> > > LP-11. The sensor is then woken up only at s_stream time.
> > >
> > > This preserves all LP-11 compliance improvements from
> > > commit 092e8eb90a7d ("media: i2c: ov5645: Fix power sequence") while
> > > eliminating the CRC errors on RK3576.
> > >
> > > Fixes: 092e8eb90a7d ("media: i2c: ov5645: Fix power sequence")
> > > Signed-off-by: Xiaolei Wang <xiaoleiwangxiaolei@xxxxxxxxx>
> > > ---
> > >   drivers/media/i2c/ov5645.c | 3 ++-
> > >   1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/media/i2c/ov5645.c b/drivers/media/i2c/ov5645.c
> > > index c772ef6e51d2..be85e0155b81 100644
> > > --- a/drivers/media/i2c/ov5645.c
> > > +++ b/drivers/media/i2c/ov5645.c
> > > @@ -351,7 +351,8 @@ static const struct reg_value ov5645_global_init_setting[] = {
> > >   	{ 0x3008, 0x02 },
> > >   	{ OV5645_IO_MIPI_CTRL00, 0x40 },
> > >   	{ OV5645_MIPI_CTRL00, 0x24 },
> > > -	{ OV5645_PAD_OUTPUT00, 0x70 }
> > > +	{ OV5645_PAD_OUTPUT00, 0x70 },
> > > +	{ 0x3008, 0x42 }
> While at it, please use the register macro.
Will do in v2.
> > Is the earlier write of 0x3008 still appropriate?
> There are four earlier writes of register 0x3008. The whole
> initialization sequence likely needs a cleanup.

The ov5645_global_init_setting register may come directly from

the manufacturer.

 I gave this a try. Three of the four writes can simply be dropped,

  leaving only the { 0x3008, 0x42 } near the beginning of the table:

        { 0x5a24, 0x00 },
  -     { 0x3008, 0x02 },
        { 0x3503, 0x00 },
        ...
        { 0x0601, 0x02 },
  -     { 0x3008, 0x42 },
  -     { 0x3008, 0x02 },
        { OV5645_IO_MIPI_CTRL00, 0x40 },

I tested this change on the Rockchip 3576 and IMX8MP platforms and found 
no problems.


>   It's not clear why
> software suspend needs to be disabled briefly during initialization.

Yes, I noticed that the driver was configured with software suspend upon

power-up at the initial commit.

thanks

xiaolei

> > >   };
> > >   
> > >   static const struct reg_value ov5645_setting_sxga[] = {