Re: mmc: core: Fix access to HS400-ES devices

From: Heiko Stübner
Date: Fri Mar 10 2017 - 03:46:16 EST


Am Mittwoch, 1. März 2017, 14:11:47 CET schrieb Guenter Roeck:
> HS400-ES devices fail to initialize with the following error messages.
>
> mmc1: power class selection to bus width 8 ddr 0 failed
> mmc1: error -110 whilst initialising MMC card
>
> This was seen on Samsung Chromebook Plus. Code analysis points to
> commit 3d4ef329757c ("mmc: core: fix multi-bit bus width without
> high-speed mode"), which attempts to set the bus width for all but
> HS200 devices unconditionally. However, for HS400-ES, the bus width
> is already selected.
>
> Cc: Anssi Hannula <anssi.hannula@xxxxxxxxxx>
> Cc: Douglas Anderson <dianders@xxxxxxxxxxxx>
> Cc: Brian Norris <briannorris@xxxxxxxxxxxx>
> Fixes: 3d4ef329757c ("mmc: core: fix multi-bit bus width ...")
> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> Reviewed-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxx>

On a rk3399-kevin and the current mainline kernel from 20170309 it makes the
issue go away and the emmc work again, so

Tested-by: Heiko Stuebner <heiko@xxxxxxxxx>