Re: [PATCH] mmc: dw_mmc-rockchip: add pinctrl support

[Shawn Lin]

On 2016/1/19 19:45, Caesar Wang wrote:
> å 2016å01æ19æ 19:07, Shawn Lin åé:
> > On 2016/1/19 18:07, Heiko Stuebner wrote:
> > > Hi Shawn,
> > >
> > > Am Dienstag, 19. Januar 2016, 17:52:45 schrieb Shawn Lin:
> > > > We find rk3368 fail to enumerate sd card since
> > > > the default state is gpio function. Meahwhile, lots of
> > > > rockchip platform dts file assign pinctrl to dw_mmc but actually
> > > > dw_mmc never use it. Fortunately, those platforms' default io
> > > > state is sdmmc function, but no always right for all.
> > > >
> > > > Cc: Heiko Stuebner <heiko@xxxxxxxxx>
> > > > Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> > >
> > > I do believe any issue you see, must come from somewhere else,
> > > because the
> > > driver-core does in drivers/base/dd.c really_probe():
> > >     pinctrl_bind_pins()
> >
> > yes, pinctrl_bind_pins does turn pinctrl state. But I try debug a little
> > more and seems somewhere else switch the state before dw_mmc probe.
> > Now I *guess* that may relate to our ATF or MCU firmware since
> > rk3368's sdmmc io can also be used as mcu_jtag for system debug. I
> > need to double check that point, thanks.
>
> Yep,  maybe that's related to the firmware setting.
> I guess you can repro this issue on RK3368 platform.
> At least until now, the RK3036, RK3288....that's work well.

Hi Caesar,

Then I check this issue with MCU firmware guys and it does force
pin setting into mcu_jtag functionã Now I can see only 3368 apply
MCU firmware, right? Another thing, seems old version firmware didn't
break the sdmmc function.

I think it's better to slove this problem in firmware side,
not Linux.  So, abandon this patch!


> > Hi Caesar,
> > does your patch able to consider adding SDMMC/CPU_JTAG/MCU_JTAG
> > managment for rk3368 as well?
>
> That's no related,  I will add the sdmmc node and check it on tomorrow
> if the time can be availabled.
>
>
> > > which in turn already does the needed pinctrl state handling.
> > >
> > > So that default-state should be set up even before the dwmmc probe
> > > function
> > > is called.
> > >
> > > The sharing between sdmmc and uart2 pins is the same on the rk3036
> > > and so
> > > far Caesar seems to have been able to switch the pin-state to sdmmc
> > > without
> > > touching the dw_mmc driver itself.
>
> Yep, that's working on rk3036 kylin board.
>
>
> ---
> Thanks,
> Caesar


--
Best Regards
Shawn Lin