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

From: Caesar Wang
Date: Tue Jan 19 2016 - 06:45:20 EST



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,
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