Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753292AbdHIRTK (ORCPT ); Wed, 9 Aug 2017 13:19:10 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:38704 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752916AbdHIQxr (ORCPT ); Wed, 9 Aug 2017 12:53:47 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ludovic Desroches , Adrian Hunter , Ulf Hansson Subject: [PATCH 4.12 014/106] mmc: sdhci-of-at91: force card detect value for non removable devices Date: Wed, 9 Aug 2017 09:51:58 -0700 Message-Id: <20170809164517.877633436@linuxfoundation.org> X-Mailer: git-send-email 2.14.0 In-Reply-To: <20170809164515.714288642@linuxfoundation.org> References: <20170809164515.714288642@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3159 Lines: 92 4.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ludovic Desroches commit 7a1e3f143176e8ebdb2f5a9b3b47abc18b879d90 upstream. When the device is non removable, the card detect signal is often used for another purpose i.e. muxed to another SoC peripheral or used as a GPIO. It could lead to wrong behaviors depending the default value of this signal if not muxed to the SDHCI controller. Fixes: bb5f8ea4d514 ("mmc: sdhci-of-at91: introduce driver for the Atmel SDMMC") Signed-off-by: Ludovic Desroches Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/host/sdhci-of-at91.c | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) --- a/drivers/mmc/host/sdhci-of-at91.c +++ b/drivers/mmc/host/sdhci-of-at91.c @@ -31,6 +31,7 @@ #define SDMMC_MC1R 0x204 #define SDMMC_MC1R_DDR BIT(3) +#define SDMMC_MC1R_FCD BIT(7) #define SDMMC_CACR 0x230 #define SDMMC_CACR_CAPWREN BIT(0) #define SDMMC_CACR_KEY (0x46 << 8) @@ -43,6 +44,15 @@ struct sdhci_at91_priv { struct clk *mainck; }; +static void sdhci_at91_set_force_card_detect(struct sdhci_host *host) +{ + u8 mc1r; + + mc1r = readb(host->ioaddr + SDMMC_MC1R); + mc1r |= SDMMC_MC1R_FCD; + writeb(mc1r, host->ioaddr + SDMMC_MC1R); +} + static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock) { u16 clk; @@ -110,10 +120,18 @@ void sdhci_at91_set_uhs_signaling(struct sdhci_set_uhs_signaling(host, timing); } +static void sdhci_at91_reset(struct sdhci_host *host, u8 mask) +{ + sdhci_reset(host, mask); + + if (host->mmc->caps & MMC_CAP_NONREMOVABLE) + sdhci_at91_set_force_card_detect(host); +} + static const struct sdhci_ops sdhci_at91_sama5d2_ops = { .set_clock = sdhci_at91_set_clock, .set_bus_width = sdhci_set_bus_width, - .reset = sdhci_reset, + .reset = sdhci_at91_reset, .set_uhs_signaling = sdhci_at91_set_uhs_signaling, .set_power = sdhci_at91_set_power, }; @@ -324,6 +342,21 @@ static int sdhci_at91_probe(struct platf host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION; } + /* + * If the device attached to the MMC bus is not removable, it is safer + * to set the Force Card Detect bit. People often don't connect the + * card detect signal and use this pin for another purpose. If the card + * detect pin is not muxed to SDHCI controller, a default value is + * used. This value can be different from a SoC revision to another + * one. Problems come when this default value is not card present. To + * avoid this case, if the device is non removable then the card + * detection procedure using the SDMCC_CD signal is bypassed. + * This bit is reset when a software reset for all command is performed + * so we need to implement our own reset function to set back this bit. + */ + if (host->mmc->caps & MMC_CAP_NONREMOVABLE) + sdhci_at91_set_force_card_detect(host); + pm_runtime_put_autosuspend(&pdev->dev); return 0;