From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754032AbaIOKJJ (ORCPT ); Mon, 15 Sep 2014 06:09:09 -0400 Received: from mail-oi0-f42.google.com ([209.85.218.42]:51459 "EHLO mail-oi0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753350AbaIOKJI (ORCPT ); Mon, 15 Sep 2014 06:09:08 -0400 MIME-Version: 1.0 In-Reply-To: <54110B29.7030303@samsung.com> References: <1410265614-3275-1-git-send-email-jean-michel.hautbois@vodalys.com> <54110B29.7030303@samsung.com> From: Jean-Michel Hautbois Date: Mon, 15 Sep 2014 12:08:47 +0200 X-Google-Sender-Auth: tLssO6nlTWvmC-e_KqkoLM8N88c Message-ID: Subject: Re: [PATCH] mmc: Add delay between CMD6 and CMD13 for Sandisk eMMC cards To: Jaehoon Chung Cc: linux-kernel , "linux-mmc@vger.kernel.org" , "tgih.jun@samsung.com" , Ulf Hansson , Chris Ball Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jaehoon, > 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. Yes >> >> 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? Well, this is difficult to verify, I know that on all my SDIN5D1-2G I have this MANFID different from what is defined by CID_MANFID_SANDISK. How should I use MMC_FIXUP ? Like this ? MMC_FIXUP("SEM02G", 0x45, CID_OEMID_ANY, add_quirk, MMC_QUIRK_INAND_CMD13) ? If so, can I use : if (card->quirks & MMC_QUIRK_INAND_CMD38) msleep(1); In drivers/mmc/core/mmc_ops.c ? Is this the good way ? Thanks, JM