Re: [PATCH] media: dw9714: Fix powerup sequence

[Ricardo Ribalda]

On Mon, 22 Dec 2025 at 18:21, Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> wrote:
>
> Hi Ricardo,
>
> On Mon, Dec 15, 2025 at 09:46:46AM +0100, Ricardo Ribalda wrote:
> > Hi Hans
> >
> > On Wed, 10 Dec 2025 at 09:21, <johannes.goede@xxxxxxxxxxxxxxxx> wrote:
> > >
> > > Hi,
> > >
> > > On 10-Dec-25 8:53 AM, Ricardo Ribalda wrote:
> > > > We have experienced seen multiple I2C errors while doing stress test on
> > > > the module:
> > > >
> > > > dw9714 i2c-PRP0001:01: dw9714_vcm_resume I2C failure: -5
> > > > dw9714 i2c-PRP0001:01: I2C write fail
> > > >
> > > > Inspecting the powerup sequence we found that it does not match the
> > > > documentation at:
> > > > https://blog.arducam.com/downloads/DW9714A-DONGWOON(Autofocus_motor_manual).pdf
> > > >
> > > > """
> > > > (2) DW9714A requires waiting time of 12ms after power on. During this
> > > > waiting time, the offset calibration of internal amplifier is
> > > > operating for minimization of output offset current .
> > > > """
> > > >
> > > > This patch increases the powerup delay to follow the documentation.
> > > >
> > > > Fixes: 9d00ccabfbb5 ("media: i2c: dw9714: Fix occasional probe errors")
> > > > Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
> > >
> > > Thanks, patch looks good to me:
> > >
> > > Reviewed-by: Hans de Goede <johannes.goede@xxxxxxxxxxxxxxxx>
> >
> > Some tags for the record
> >
> > Tested-by: Neil Sun <neil.sun@xxxxxxxxxxxxxxxxxx>
> > Co-developed-by: Naomi Huang <naomi.huang@xxxxxxxxxxxxxxxxxx>
>
> Co-developed-by: requires Sob. Do we have that as well?

Good point, I did not get a explicit Sob.

I wanted to give them credit for this patch, because they did a great
job reporting the issue.

Let's do a Reported-by with no Closes. Does that work for you?

Thanks
>
> --
> Regards,
>
> Sakari Ailus



-- 
Ricardo Ribalda