diff options
| author | Andrew Gabbasov <andrew_gabbasov@mentor.com> | 2014-12-25 10:22:25 -0600 |
|---|---|---|
| committer | Pantelis Antoniou <pantelis.antoniou@konsulko.com> | 2015-01-19 17:41:52 +0200 |
| commit | fc5b32fbf3bd43dabaf409e424e0bfb9a1b4df26 (patch) | |
| tree | 534a345ad2ff73c1a2b81acd73e20a027f5d9ed6 /drivers/mmc/mmc.c | |
| parent | bf4770731c1fbd23befb1ffcd0436df2262a3199 (diff) | |
mmc: Skip changing bus width for MMC cards earlier than version 4.0
Wider bus widths (larger than default 1 bit) appeared in MMC standard
version 4.0. So, for MMC cards of any earlier version trying to change
the bus width (including ext_csd comparison) does not make any sense.
It may work incorrectly and at least cause unnecessary timeouts.
So, just skip the entire bus width related activity for earlier versions.
Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Tested-by: Alexey Brodkin <abrodkin@synopsys.com>
Diffstat (limited to 'drivers/mmc/mmc.c')
| -rw-r--r-- | drivers/mmc/mmc.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index bdd7894231..b8039cd092 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -486,7 +486,7 @@ static int mmc_change_freq(struct mmc *mmc) char cardtype; int err; - mmc->card_caps = MMC_MODE_4BIT | MMC_MODE_8BIT; + mmc->card_caps = 0; if (mmc_host_is_spi(mmc)) return 0; @@ -495,6 +495,8 @@ static int mmc_change_freq(struct mmc *mmc) if (mmc->version < MMC_VERSION_4) return 0; + mmc->card_caps |= MMC_MODE_4BIT | MMC_MODE_8BIT; + err = mmc_send_ext_csd(mmc, ext_csd); if (err) @@ -1349,7 +1351,8 @@ static int mmc_startup(struct mmc *mmc) mmc->tran_speed = 50000000; else mmc->tran_speed = 25000000; - } else { + } else if (mmc->version >= MMC_VERSION_4) { + /* Only version 4 of MMC supports wider bus widths */ int idx; /* An array of possible bus widths in order of preference */ |