Re: gc2145 camera driver (front camera on PinePhone)

From: Alain Volmat
Date: Tue Aug 29 2023 - 10:41:51 EST


Hi Andrey,

sorry for the delay and huge thanks for the effort of adding parallel
support into the driver.

Yeah pushing this driver is still in my todo and your effort for the
parallel part helps me a lot.

Since you already have a commit which adds the parallel support, what
about I prepare the driver with only CSI support for the time being
(after cleanup as you also suggested) and then you can push additionnal
patches on top of it to add parallel support ?

Regards,
Alain

On Sun, Aug 20, 2023 at 08:38:44PM +0300, Andrey Skvortsov wrote:
> Hi Alain,
>
> > we are also using the GC2145 sensor but in a CSI based environment.
> >
> > We are in contact with GalaxyCore and following discussions we had with them
> > and data they provided us with, we've made a driver for that, supporting for
> > the time being 3 different resolutions via the CSI interface.
> >
> > The driver is available on the STMicroelectronics STM32 github [1].
> >
> > If you are ok with that, we could go further upstreaming it while testing/adding
> > features necessary for the PinePhone.
> >
> > [1] https://github.com/STMicroelectronics/linux/blob/v5.15-stm32mp/drivers/media/i2c/gc2145.c
>
> I've implemented basic parallel bus support to check your driver [1] on
> the PinePhone. My changes are here [2].
> With your driver results are much better in compare to Megi's
> driver (I'm still glad, that Megi has written one). See pictures for
> comparison here [3]. Access to vendor support and (probably)
> documentation gives great results.
>
> I'd recommend to replace more of hard-coded parts of initialization
> sequences with functions like in proposed Megi's driver. So this will
> be clearer what different register values mean. Since you have access
> to support channel/documentation it'd be easier for you to do.
>
> It'd be nice to have at least some gc2145 driver in mainline. Do you
> still have plans/time to mainline driver?
>
> P.S.
> Alain, I don't see your address in the list of recipients of last Pavel's
> response. In case you have not received it, it's here [4].
>
> 1. https://github.com/STMicroelectronics/linux/blob/v6.1-stm32mp/drivers/media/i2c/gc2145.c
> 2. https://github.com/AndreySV/linux/commit/f06ff60eb7a664dcafa8d40901a1ab0f59071529
> 3. https://github.com/AndreySV/linux/issues/1
> 4. https://lwn.net/ml/linux-kernel/Y6tGfxrq/Mh1JoA9@xxxxxxxxxx
> --
> Best regards,
> Andrey Skvortsov