Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752285Ab1DUS0k (ORCPT ); Thu, 21 Apr 2011 14:26:40 -0400 Received: from cantor.suse.de ([195.135.220.2]:59493 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751381Ab1DUS0j (ORCPT ); Thu, 21 Apr 2011 14:26:39 -0400 Date: Thu, 21 Apr 2011 20:26:38 +0200 Message-ID: From: Takashi Iwai To: Chris Ball Cc: Aries Lee , linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] [PATCH v2] mmc: Fix read-only detection with JMicron 388 chip User-Agent: Wanderlust/2.15.6 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.7 Emacs/23.2 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3251 Lines: 109 On HP laptops with JMicron 388 chip, the write-locked SD card isn't detected correctly as read-only in many cases. This is because the PRESENT_STATE register becomes unsable just after plugging, and it returns the WRITE_PROTECT bit wrongly at the first read. This patch fixes the read-only detection by adding a new sdhci quirk indicating to check the register more intensively with a relatively long delay. The patch is tested with 2.6.39-rc4 kernel. Cc: Aries Lee Signed-off-by: Takashi Iwai --- v1->v2 rewritten to use a quirk drivers/mmc/host/sdhci-pci.c | 5 +++++ drivers/mmc/host/sdhci.c | 28 ++++++++++++++++++++++++---- include/linux/mmc/sdhci.h | 2 ++ 3 files changed, 31 insertions(+), 4 deletions(-) diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c index a136be7..5781395 100644 --- a/drivers/mmc/host/sdhci-pci.c +++ b/drivers/mmc/host/sdhci-pci.c @@ -329,6 +329,11 @@ static int jmicron_probe(struct sdhci_pci_chip *chip) return ret; } + /* quirk for unsable RO-detection on JM388 chips */ + if (chip->pdev->device == PCI_DEVICE_ID_JMICRON_JMB388_SD || + chip->pdev->device == PCI_DEVICE_ID_JMICRON_JMB388_ESD) + chip->quirks |= SDHCI_QUIRK_UNSTABLE_RO_DETECT; + return 0; } diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 9e15f41..8097171 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1237,14 +1237,11 @@ out: spin_unlock_irqrestore(&host->lock, flags); } -static int sdhci_get_ro(struct mmc_host *mmc) +static int check_ro(struct sdhci_host *host) { - struct sdhci_host *host; unsigned long flags; int is_readonly; - host = mmc_priv(mmc); - spin_lock_irqsave(&host->lock, flags); if (host->flags & SDHCI_DEVICE_DEAD) @@ -1262,6 +1259,29 @@ static int sdhci_get_ro(struct mmc_host *mmc) !is_readonly : is_readonly; } +#define SAMPLE_COUNT 5 + +static int sdhci_get_ro(struct mmc_host *mmc) +{ + struct sdhci_host *host; + int i, ro_count; + + host = mmc_priv(mmc); + + if (!(host->quirks & SDHCI_QUIRK_UNSTABLE_RO_DETECT)) + return check_ro(host); + + ro_count = 0; + for (i = 0; i < SAMPLE_COUNT; i++) { + if (check_ro(host)) { + if (++ro_count > SAMPLE_COUNT / 2) + return 1; + } + msleep(30); + } + return 0; +} + static void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable) { struct sdhci_host *host; diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h index 83bd9f7..92e1c9a 100644 --- a/include/linux/mmc/sdhci.h +++ b/include/linux/mmc/sdhci.h @@ -85,6 +85,8 @@ struct sdhci_host { #define SDHCI_QUIRK_NO_HISPD_BIT (1<<29) /* Controller treats ADMA descriptors with length 0000h incorrectly */ #define SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC (1<<30) +/* The read-only detection via SDHCI_PRESENT_STATE register is unstable */ +#define SDHCI_QUIRK_UNSTABLE_RO_DETECT (1<<31) int irq; /* Device IRQ */ void __iomem *ioaddr; /* Mapped address */ -- 1.7.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/