From d16f57700475f670ca2828c150a34fa7102a05fc Mon Sep 17 00:00:00 2001 From: Pierre Ossman Date: Sun, 31 Aug 2008 17:22:46 +0200 Subject: [PATCH] sdio: high-speed support Signed-off-by: Pierre Ossman --- drivers/mmc/core/sdio.c | 52 ++++++++++++++++++++++++++++++++++++++--- 1 file changed, 49 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c index 4eab79e09ccc..fb99ccff9080 100644 --- a/drivers/mmc/core/sdio.c +++ b/drivers/mmc/core/sdio.c @@ -164,6 +164,36 @@ static int sdio_enable_wide(struct mmc_card *card) return 0; } +/* + * Test if the card supports high-speed mode and, if so, switch to it. + */ +static int sdio_enable_hs(struct mmc_card *card) +{ + int ret; + u8 speed; + + if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED)) + return 0; + + if (!card->cccr.high_speed) + return 0; + + ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed); + if (ret) + return ret; + + speed |= SDIO_SPEED_EHS; + + ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL); + if (ret) + return ret; + + mmc_card_set_highspeed(card); + mmc_set_timing(card->host, MMC_TIMING_SD_HS); + + return 0; +} + /* * Host is being removed. Free up the current card. */ @@ -333,10 +363,26 @@ int mmc_attach_sdio(struct mmc_host *host, u32 ocr) goto remove; /* - * No support for high-speed yet, so just set - * the card's maximum speed. + * Switch to high-speed (if supported). */ - mmc_set_clock(host, card->cis.max_dtr); + err = sdio_enable_hs(card); + if (err) + goto remove; + + /* + * Change to the card's maximum speed. + */ + if (mmc_card_highspeed(card)) { + /* + * The SDIO specification doesn't mention how + * the CIS transfer speed register relates to + * high-speed, but it seems that 50 MHz is + * mandatory. + */ + mmc_set_clock(host, 50000000); + } else { + mmc_set_clock(host, card->cis.max_dtr); + } /* * Switch to wider bus (if supported). -- 2.20.1