From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman Subject: [PATCH 4.4 142/342] mmc: sdhci-pci: Fix card detect race for Intel BXT/APL To: Cc: Greg Kroah-Hartman , , Adrian Hunter , Ulf Hansson Message-Id: <20160301234532.557334574@linuxfoundation.org> In-Reply-To: <20160301234527.990448862@linuxfoundation.org> References: <20160301234527.990448862@linuxfoundation.org> Date: Tue, 01 Mar 2016 23:54:30 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Adrian Hunter commit 163cbe31e5163459908a41a2b4e0d33a28fd557a upstream. Intel BXT/APL use a card detect GPIO however the host controller will not enable bus power unless it's card detect also reflects the presence of a card. Unfortunately those 2 things race which can result in commands not starting, after which the controller does nothing and there is a 10 second wait for the driver's 10-second timer to timeout. That is fixed by having the driver look also at the present state register to determine if the card is present. Consequently, provide a 'get_cd' mmc host operation for BXT/APL that does that. Signed-off-by: Adrian Hunter Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/host/sdhci-pci-core.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) --- a/drivers/mmc/host/sdhci-pci-core.c +++ b/drivers/mmc/host/sdhci-pci-core.c @@ -330,6 +330,33 @@ static void spt_read_drive_strength(stru sdhci_pci_spt_drive_strength = 0x10 | ((val >> 12) & 0xf); } +static int bxt_get_cd(struct mmc_host *mmc) +{ + int gpio_cd = mmc_gpio_get_cd(mmc); + struct sdhci_host *host = mmc_priv(mmc); + unsigned long flags; + int ret = 0; + + if (!gpio_cd) + return 0; + + pm_runtime_get_sync(mmc->parent); + + spin_lock_irqsave(&host->lock, flags); + + if (host->flags & SDHCI_DEVICE_DEAD) + goto out; + + ret = !!(sdhci_readl(host, SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT); +out: + spin_unlock_irqrestore(&host->lock, flags); + + pm_runtime_mark_last_busy(mmc->parent); + pm_runtime_put_autosuspend(mmc->parent); + + return ret; +} + static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot) { slot->host->mmc->caps |= MMC_CAP_8_BIT_DATA | MMC_CAP_NONREMOVABLE | @@ -362,6 +389,10 @@ static int byt_sd_probe_slot(struct sdhc slot->cd_con_id = NULL; slot->cd_idx = 0; slot->cd_override_level = true; + if (slot->chip->pdev->device == PCI_DEVICE_ID_INTEL_BXT_SD || + slot->chip->pdev->device == PCI_DEVICE_ID_INTEL_APL_SD) + slot->host->mmc_host_ops.get_cd = bxt_get_cd; + return 0; }