From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932952AbcKKNUy (ORCPT ); Fri, 11 Nov 2016 08:20:54 -0500 Received: from mga01.intel.com ([192.55.52.88]:28368 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754011AbcKKNUx (ORCPT ); Fri, 11 Nov 2016 08:20:53 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,621,1473145200"; d="scan'208";a="1067175797" Subject: Re: [PATCH] mmc: sdhci-of-esdhc: fixup PRESENT_STATE read To: Michael Walle , linux-kernel@vger.kernel.org References: <1478796456-30549-1-git-send-email-michael@walle.cc> Cc: linux-mmc@vger.kernel.org, Ulf Hansson , yangbo lu From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: <0a5454e6-efa6-744e-4a2d-123a47e7cc40@intel.com> Date: Fri, 11 Nov 2016 15:15:55 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <1478796456-30549-1-git-send-email-michael@walle.cc> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/11/16 18:47, 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 Could add a Fixes tag here. > --- > drivers/mmc/host/sdhci-of-esdhc.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c > index fb71c86..243fee9 100644 > --- a/drivers/mmc/host/sdhci-of-esdhc.c > +++ b/drivers/mmc/host/sdhci-of-esdhc.c > @@ -66,6 +66,18 @@ static u32 esdhc_readl_fixup(struct sdhci_host *host, > return ret; > } > } > + /* > + * The DAT[3:0] line signal levels and the CMD line signal level is > + * not compatible with standard SDHC reegister. Move the corresponding reegister -> register > + * bits around. > + */ > + if (spec_reg == SDHCI_PRESENT_STATE) { > + ret = value & 0xf8000000; > + ret |= (value >> 4) & SDHCI_DATA_LVL_MASK; > + ret |= (value << 1) & 0x01000000; > + return ret; SDHCI also uses other bits in SDHCI_PRESENT_STATE like SDHCI_CMD_INHIBIT and SDHCI_DATA_INHIBIT etc, but this looks like all those bits will be zero. Is that right? > + } > + > ret = value; > return ret; > } >