From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jaehoon Chung Subject: Re: [PATCH] mmc: Add delay between CMD6 and CMD13 for Sandisk eMMC cards Date: Thu, 11 Sep 2014 11:38:33 +0900 Message-ID: <54110B29.7030303@samsung.com> References: <1410265614-3275-1-git-send-email-jean-michel.hautbois@vodalys.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mailout3.samsung.com ([203.254.224.33]:54742 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752035AbaIKCig (ORCPT ); Wed, 10 Sep 2014 22:38:36 -0400 In-reply-to: <1410265614-3275-1-git-send-email-jean-michel.hautbois@vodalys.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Jean-Michel Hautbois , linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org Cc: tgih.jun@samsung.com, ulf.hansson@linaro.org, chris@printf.net Hi, On 09/09/2014 09:26 PM, Jean-Michel Hautbois wrote: > Tested on a i.MX6 board, with Sandisk SDIN5D1-2G. > Without this patch, I/O errors occur. > This eMMC seems to have a different Manufacturer ID as it reads 0x45 > and not 0x2 as specified in datasheet. I think this patch don't merge into mainline. This is not solution for problem. you mentioned the below comment, this is workaround. > > Signed-off-by: Jean-Michel Hautbois > --- > drivers/mmc/core/mmc_ops.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c > index f51b5ba..91babaa 100644 > --- a/drivers/mmc/core/mmc_ops.c > +++ b/drivers/mmc/core/mmc_ops.c > @@ -458,6 +458,15 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value, > if (!use_busy_signal) > return 0; > > + /* WORKAROUND: for Sandisk eMMC cards, it might need certain delay > + * before sending CMD13 after CMD6 > + * On SDIN5D1-2G MANFID is 0x45 and not 0x2 as specified in datasheet > + */ > + if (card->cid.manfid == CID_MANFID_SANDISK || > + card->cid.manfid == 0x45) { > + msleep(1); > + } If it's a general problem of Sandisk SDIN5D1-2G, I think you need to verify this problem. And can you use the MMC_FIXUP() and QUIRK? Best Regards, Jaehoon Chung > + > /* > * CRC errors shall only be ignored in cases were CMD13 is used to poll > * to detect busy completion. >