From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: [PATCH 2/4] mmc: sdhci: Fix recovery from tuning timeout Date: Wed, 30 Nov 2016 11:20:12 +0200 Message-ID: <1480497614-3501-3-git-send-email-adrian.hunter@intel.com> References: <1480497614-3501-1-git-send-email-adrian.hunter@intel.com> Return-path: Received: from mga02.intel.com ([134.134.136.20]:18535 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755800AbcK3JZV (ORCPT ); Wed, 30 Nov 2016 04:25:21 -0500 In-Reply-To: <1480497614-3501-1-git-send-email-adrian.hunter@intel.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Ulf Hansson Cc: linux-mmc , Dan O'Donovan Clearing the tuning bits should reset the tuning circuit. However there is more to do. Reset the command and data lines for good measure, and then for eMMC ensure the card is not still trying to process a tuning command by sending a stop command. Note the JEDEC eMMC specification says the stop command (CMD12) can be used to stop a tuning command (CMD21) whereas the SD specification is silent on the subject with respect to the SD tuning command (CMD19). Considering that CMD12 is not a valid SDIO command, the stop command is sent only when the tuning command is CMD21 i.e. for eMMC. That addresses cases seen so far which have been on eMMC. Note that this replaces the commit fe5fb2e3b58f ("mmc: sdhci: Reset cmd and data circuits after tuning failure") which is being reverted for v4.9+. Signed-off-by: Adrian Hunter Tested-by: Dan O'Donovan Cc: stable@vger.kernel.org --- drivers/mmc/host/sdhci.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index e761fe2aa99e..1d72a51287d4 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2095,7 +2095,27 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) ctrl &= ~SDHCI_CTRL_EXEC_TUNING; sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2); + sdhci_do_reset(host, SDHCI_RESET_CMD); + sdhci_do_reset(host, SDHCI_RESET_DATA); + err = -EIO; + + if (cmd.opcode != MMC_SEND_TUNING_BLOCK_HS200) + goto out; + + sdhci_writel(host, host->ier, SDHCI_INT_ENABLE); + sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE); + + spin_unlock_irqrestore(&host->lock, flags); + + memset(&cmd, 0, sizeof(cmd)); + cmd.opcode = MMC_STOP_TRANSMISSION; + cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC; + cmd.busy_timeout = 50; + mmc_wait_for_cmd(mmc, &cmd, 0); + + spin_lock_irqsave(&host->lock, flags); + goto out; } -- 1.9.1