From af51715079e7fb6b290e1881d63d815dc4de5011 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Wed, 8 Aug 2007 09:11:32 -0700 Subject: MMC core learns about SPI Teach the MMC/SD/SDIO core about using SPI mode. - Use mmc_host_is_spi() so enumeration works through SPI signaling and protocols, not just the native versions. - Provide the SPI response type flags with each request issued, including requests from the new lock/unlock code. - Understand that cmd->resp[0] and mmc_get_status() results for SPI return different values than for "native" MMC/SD protocol; this affects resetting, checking card lock status, and some others. - Understand that some commands act a bit differently ... notably: * OP_COND command doesn't return the OCR * APP_CMD status doesn't have an R1_APP_CMD analogue Those changes required some new and updated primitives: - Provide utilities to access two SPI-only requests, and one request that wasn't previously needed: * mmc_spi_read_ocr() ... SPI only * mmc_spi_set_crc() ... SPI only (override by module parm) * mmc_send_cid() ... for use without broadcast mode - Updated internal routines: * Previous mmc_send_csd() modified into mmc_send_cxd_native(); it uses native "R2" responses, which include 16 bytes of data. * Previous mmc_send_ext_csd() becomes new mmc_send_cxd_data() helper for command-and-data access * Bugfix to that mmc_send_cxd_data() code: dma-to-stack is unsafe/nonportable, so kmalloc a bounce buffer instead. - Modified mmc_send_ext_csd() now uses mmc_send_cxd_data() helper - Modified mmc_send_csd(), and new mmc_spi_send_cid(), routines use those helper routines based on whether they're native or SPI The newest categories of cards supported by the MMC stack aren't expected to work yet with SPI: MMC or SD cards with over 4GB data, and SDIO. All those cards support SPI mode, so eventually they should work too. Signed-off-by: David Brownell Signed-off-by: Pierre Ossman --- drivers/mmc/core/sd.c | 48 ++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 38 insertions(+), 10 deletions(-) (limited to 'drivers/mmc/core/sd.c') diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index c86588fdaae..d1c1e0f592f 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -322,10 +322,22 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, if (err) goto err; + /* + * For SPI, enable CRC as appropriate. + */ + if (mmc_host_is_spi(host)) { + err = mmc_spi_set_crc(host, use_spi_crc); + if (err) + goto err; + } + /* * Fetch CID from card. */ - err = mmc_all_send_cid(host, cid); + if (mmc_host_is_spi(host)) + err = mmc_send_cid(host, cid); + else + err = mmc_all_send_cid(host, cid); if (err) goto err; @@ -351,13 +363,15 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, } /* - * Set card RCA. + * For native busses: get card RCA and quit open drain mode. */ - err = mmc_send_relative_addr(host, &card->rca); - if (err) - goto free_card; + if (!mmc_host_is_spi(host)) { + err = mmc_send_relative_addr(host, &card->rca); + if (err) + goto free_card; - mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL); + mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL); + } if (!oldcard) { /* @@ -377,9 +391,11 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, /* * Select card, as all following commands rely on that. */ - err = mmc_select_card(card); - if (err) - goto free_card; + if (!mmc_host_is_spi(host)) { + err = mmc_select_card(card); + if (err) + goto free_card; + } if (!oldcard) { /* @@ -562,7 +578,8 @@ static void mmc_sd_suspend(struct mmc_host *host) BUG_ON(!host->card); mmc_claim_host(host); - mmc_deselect_cards(host); + if (!mmc_host_is_spi(host)) + mmc_deselect_cards(host); host->card->state &= ~MMC_STATE_HIGHSPEED; mmc_release_host(host); } @@ -622,6 +639,17 @@ int mmc_attach_sd(struct mmc_host *host, u32 ocr) mmc_attach_bus(host, &mmc_sd_ops); + /* + * We need to get OCR a different way for SPI. + */ + if (mmc_host_is_spi(host)) { + mmc_go_idle(host); + + err = mmc_spi_read_ocr(host, 0, &ocr); + if (err) + goto err; + } + /* * Sanity check the voltages that the card claims to * support. -- cgit v1.2.3