diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mmc/core/sdio.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c index 62df8e177585..48c465a8e34e 100644 --- a/drivers/mmc/core/sdio.c +++ b/drivers/mmc/core/sdio.c @@ -138,6 +138,32 @@ out: return ret; } +static int sdio_enable_wide(struct mmc_card *card) +{ + int ret; + u8 ctrl; + + if (!(card->host->caps & MMC_CAP_4_BIT_DATA)) + return 0; + + if (card->cccr.low_speed && !card->cccr.wide_bus) + return 0; + + ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl); + if (ret) + return ret; + + ctrl |= SDIO_BUS_WIDTH_4BIT; + + ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL); + if (ret) + return ret; + + mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4); + + return 0; +} + /* * Host is being removed. Free up the current card. */ @@ -300,6 +326,13 @@ int mmc_attach_sdio(struct mmc_host *host, u32 ocr) mmc_set_clock(host, card->cis.max_dtr); /* + * Switch to wider bus (if supported). + */ + err = sdio_enable_wide(card); + if (err) + goto remove; + + /* * Initialize (but don't add) all present functions. */ for (i = 0;i < funcs;i++) { |