diff options
| author | Shawn Lin <shawn.lin@rock-chips.com> | 2016-09-30 14:18:59 +0800 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2016-10-10 14:01:15 +0200 |
| commit | 4f25580fb84d934d7ecffa3c0aa8f10f7e23af92 (patch) | |
| tree | 624c64cb0d179ff5ef5732ce4f7d58eaf4302b59 /drivers/mmc | |
| parent | 1720d3545b772c49b2975eeb3b8f4d3f56dc2085 (diff) | |
| download | linux-4f25580fb84d934d7ecffa3c0aa8f10f7e23af92.tar.bz2 | |
mmc: core: changes frequency to hs_max_dtr when selecting hs400es
Per JESD84-B51 P49, Host need to change frequency to <=52MHz
after setting HS_TIMING to 0x1, and host may changes frequency
to <= 200MHz after setting HS_TIMING to 0x3. That means the card
expects the clock rate to increase from the current used f_init
(which is less than 400KHz, but still being less than 52MHz) to
52MHz, otherwise we find some eMMC devices significantly report
failure when sending status.
Reported-by: Xiao Yao <xiaoyao@rock-chips.com>
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Diffstat (limited to 'drivers/mmc')
| -rw-r--r-- | drivers/mmc/core/mmc.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index f4ed5accafd0..39fc5b2b96c5 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -1282,6 +1282,8 @@ static int mmc_select_hs400es(struct mmc_card *card) if (err) goto out_err; + mmc_set_clock(host, card->ext_csd.hs_max_dtr); + err = mmc_switch_status(card); if (err) goto out_err; |