From e51534c806609c806d81bfb034f02737461f855c Mon Sep 17 00:00:00 2001 From: Dong Aisheng Date: Thu, 21 Apr 2016 00:51:30 +0800 Subject: mmc: core: fix using wrong io voltage if mmc_select_hs200 fails Currently MMC core will keep going if HS200/HS timing switch failed with -EBADMSG error by the assumption that the old timing is still valid. However, for mmc_select_hs200 case, the signal voltage may have already been switched. If the timing switch failed, we should fall back to the old voltage in case the card is continue run with legacy timing. If fall back signal voltage failed, we explicitly report an EIO error to force retry during the next power cycle. Signed-off-by: Dong Aisheng Signed-off-by: Ulf Hansson --- drivers/mmc/core/mmc.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'drivers/mmc/core') diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index f99c47e003fe..e0c9a559c5fd 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -1244,10 +1244,11 @@ static int mmc_select_hs200(struct mmc_card *card) { struct mmc_host *host = card->host; bool send_status = true; - unsigned int old_timing; + unsigned int old_timing, old_signal_voltage; int err = -EINVAL; u8 val; + old_signal_voltage = host->ios.signal_voltage; if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_2V) err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120); @@ -1256,7 +1257,7 @@ static int mmc_select_hs200(struct mmc_card *card) /* If fails try again during next card power cycle */ if (err) - goto err; + return err; mmc_select_driver_type(card); @@ -1290,9 +1291,14 @@ static int mmc_select_hs200(struct mmc_card *card) } } err: - if (err) + if (err) { + /* fall back to the old signal voltage, if fails report error */ + if (__mmc_set_signal_voltage(host, old_signal_voltage)) + err = -EIO; + pr_err("%s: %s failed, error %d\n", mmc_hostname(card->host), __func__, err); + } return err; } -- cgit v1.2.3-59-g8ed1b