From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: [PATCH] mmc: core: Fix access to HS400-ES devices Date: Mon, 6 Mar 2017 19:42:53 -0800 Message-ID: <20170307034253.GA32126@roeck-us.net> References: <1488406307-8952-1-git-send-email-linux@roeck-us.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1488406307-8952-1-git-send-email-linux@roeck-us.net> Sender: linux-kernel-owner@vger.kernel.org To: Ulf Hansson Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Anssi Hannula , Douglas Anderson , Brian Norris List-Id: linux-mmc@vger.kernel.org ping ... Ulf, I know it is early for a ping. However, the patch causing all HS400-ES devices to fail already made it into various stable releases, and I think it would be very desirable to get those back to working. Thanks, Guenter On Wed, Mar 01, 2017 at 02:11:47PM -0800, Guenter Roeck wrote: > 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 > Cc: Douglas Anderson > Cc: Brian Norris > Fixes: 3d4ef329757c ("mmc: core: fix multi-bit bus width ...") > Signed-off-by: Guenter Roeck > --- > drivers/mmc/core/mmc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index 7fd722868875..b502601df228 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -1730,7 +1730,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, > err = mmc_select_hs400(card); > if (err) > goto free_card; > - } else { > + } else if (!mmc_card_hs400es(card)) { > /* Select the desired bus width optionally */ > err = mmc_select_bus_width(card); > if (err > 0 && mmc_card_hs(card)) { > -- > 2.7.4 >