From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932889AbcFGN5L (ORCPT ); Tue, 7 Jun 2016 09:57:11 -0400 Received: from mail-wm0-f52.google.com ([74.125.82.52]:38007 "EHLO mail-wm0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932337AbcFGN5J (ORCPT ); Tue, 7 Jun 2016 09:57:09 -0400 Date: Tue, 7 Jun 2016 14:57:02 +0100 From: Peter Griffin To: Lee Jones Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel@stlinux.com, ulf.hansson@linaro.org, adrian.hunter@intel.com, linux-mmc@vger.kernel.org, Arnd Bergmann Subject: Re: [PATCH] mmc: core: Fix mmc_select_hs200() regression in v4.7-rc. Message-ID: <20160607135702.GA19771@griffinp-ThinkPad-X1-Carbon-2nd> References: <1465304543-23988-1-git-send-email-peter.griffin@linaro.org> <20160607133839.GH18047@dell> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160607133839.GH18047@dell> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Lee, On Tue, 07 Jun 2016, Lee Jones wrote: > On Tue, 07 Jun 2016, Peter Griffin wrote: > > > mmc_select_bus_width() returns bus width (4 or 8) on success or > > zero if unsupported. If bus width is set successfully we then wish > > to switch to HS200 mode. > > > > This avoids the following error message in v4.70-rc2 > > > > [ 2.523674] mmc0: mmc_select_hs200 failed, error 3 > > [ 2.528516] mmc0: error 3 whilst initialising MMC card > > > > With this patch card is enumerated correctly > > > > [ 2.468065] mmc0: new HS200 MMC card at address 0001 > > [ 2.468335] mmcblk0: mmc0:0001 P1XXXX 7.20 GiB > > [ 2.468441] mmcblk0boot0: mmc0:0001 P1XXXX partition 1 2.00 MiB > > [ 2.468552] mmcblk0boot1: mmc0:0001 P1XXXX partition 2 2.00 MiB > > [ 2.468651] mmcblk0rpmb: mmc0:0001 P1XXXX partition 3 128 KiB > > [ 2.469269] mmcblk0: p1 > > > > Fixes: 287980e (remove lots of IS_ERR_VALUE abuses) > > Signed-off-by: Peter Griffin > > Cc: Arnd Bergmann > > --- > > drivers/mmc/core/mmc.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > > index c984321..aafb73d 100644 > > --- a/drivers/mmc/core/mmc.c > > +++ b/drivers/mmc/core/mmc.c > > @@ -1276,7 +1276,7 @@ static int mmc_select_hs200(struct mmc_card *card) > > * switch to HS200 mode if bus width is set successfully. > > */ > > err = mmc_select_bus_width(card); > > - if (!err) { > > + if (err > 0) { > > val = EXT_CSD_TIMING_HS200 | > > card->drive_strength << EXT_CSD_DRV_STR_SHIFT; > > err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, > > @@ -1583,7 +1583,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, > > } else if (mmc_card_hs(card)) { > > /* Select the desired bus width optionally */ > > err = mmc_select_bus_width(card); > > - if (!err) { > > + if (err > 0) { > > err = mmc_select_hs_ddr(card); > > if (err) > > goto free_card; > > Looks like this has already been 'fixed' in -rc2. Ah, it seems I was on -rc1, not -rc2 > > Although, this patch does not work for me. > mmc: fix mmc mode selection for HS-DDR and higher > > When IS_ERR_VALUE was removed from the mmc core code, it was replaced > with a simple not-zero check. This does not work, as the value checked > is the return value for mmc_select_bus_width, which returns the set > bit width on success. This made eMMC modes higher than HS-DDR unusable. > > Fix this by checking for a positive return value instead. > > Fixes: 287980e49ffc ("remove lots of IS_ERR_VALUE abuses") > Cc: Arnd Bergmann > Signed-off-by: Chen-Yu Tsai > Acked-by: Hans de Goede > Reviewed-by: Krzysztof Kozlowski > Acked-by: Jaehoon Chung > Reviewed-by: Shawn Lin > Tested-by: Marcel Ziswiler > Tested-by: Bjorn Andersson > Signed-off-by: Ulf Hansson > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index c984321..5d438ad 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -1276,7 +1276,7 @@ static int mmc_select_hs200(struct mmc_card *card) > * switch to HS200 mode if bus width is set successfully. > */ > err = mmc_select_bus_width(card); > - if (!err) { > + if (err >= 0) { This patch looks wrong to me, as if zero is returned by mmc_select_bus_width() it means setting the bus width failed, and you most likely don't want to switch to hs200 mode. Ulf - what is your opinion? regards, Peter.>