3.16.42-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Adrian Hunter <adrian.hunter@xxxxxxxxx> commit 61e53bd0047d58caee0c7170613045bf96de4458 upstream. 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 <adrian.hunter@xxxxxxxxx> Tested-by: Dan O'Donovan <dan@xxxxxxxxxx> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- drivers/mmc/host/sdhci.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1959,7 +1959,27 @@ static int sdhci_execute_tuning(struct m 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; }