From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: [PATCH v4] mmc: sdhci-of-esdhc: fixup PRESENT_STATE read Date: Tue, 15 Nov 2016 12:25:32 +0200 Message-ID: References: <1479204796-23982-1-git-send-email-michael@walle.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: Received: from mga06.intel.com ([134.134.136.31]:27732 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755484AbcKOKab (ORCPT ); Tue, 15 Nov 2016 05:30:31 -0500 In-Reply-To: <1479204796-23982-1-git-send-email-michael@walle.cc> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Michael Walle , linux-kernel@vger.kernel.org Cc: linux-mmc@vger.kernel.org, Ulf Hansson , yangbo lu , Alexander Stein On 15/11/16 12:13, Michael Walle wrote: > Since commit 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy > cards in __mmc_switch()") the ESDHC driver is broken: > mmc0: Card stuck in programming state! __mmc_switch > mmc0: error -110 whilst initialising MMC card > > Since this commit __mmc_switch() uses ->card_busy(), which is > sdhci_card_busy() for the esdhc driver. sdhci_card_busy() uses the > PRESENT_STATE register, specifically the DAT0 signal level bit. But the > ESDHC uses a non-conformant PRESENT_STATE register, thus a read fixup is > required to make the driver work again. > > Signed-off-by: Michael Walle > Fixes: 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy cards in __mmc_switch()") > Acked-by: Yangbo Lu Acked-by: Adrian Hunter > --- > v4: > - add and use SDHCI_CMD_LVL macro > - fix typo in comment, thanks alex > - add acked-by > > v3: > - explain the bits in the comments > - use bits[19:0] from the original value, all other will be taken from the > fixup value. > > v2: > - use lower bits of the original value (that was actually a typo) > - add fixes tag > - fix typo > > drivers/mmc/host/sdhci-of-esdhc.c | 14 ++++++++++++++ > drivers/mmc/host/sdhci.h | 1 + > 2 files changed, 15 insertions(+) > > diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c > index fb71c86..1bb11e4 100644 > --- a/drivers/mmc/host/sdhci-of-esdhc.c > +++ b/drivers/mmc/host/sdhci-of-esdhc.c > @@ -66,6 +66,20 @@ static u32 esdhc_readl_fixup(struct sdhci_host *host, > return ret; > } > } > + /* > + * The DAT[3:0] line signal levels and the CMD line signal level are > + * not compatible with standard SDHC register. The line signal levels > + * DAT[7:0] are at bits 31:24 and the command line signal level is at > + * bit 23. All other bits are the same as in the standard SDHC > + * register. > + */ > + if (spec_reg == SDHCI_PRESENT_STATE) { > + ret = value & 0x000fffff; > + ret |= (value >> 4) & SDHCI_DATA_LVL_MASK; > + ret |= (value << 1) & SDHCI_CMD_LVL; > + return ret; > + } > + > ret = value; > return ret; > } > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > index c722cd2..ea38962 100644 > --- a/drivers/mmc/host/sdhci.h > +++ b/drivers/mmc/host/sdhci.h > @@ -73,6 +73,7 @@ > #define SDHCI_DATA_LVL_MASK 0x00F00000 > #define SDHCI_DATA_LVL_SHIFT 20 > #define SDHCI_DATA_0_LVL_MASK 0x00100000 > +#define SDHCI_CMD_LVL 0x01000000 > > #define SDHCI_HOST_CONTROL 0x28 > #define SDHCI_CTRL_LED 0x01 >