From b57c43ad81602589afca3948a5a7121e40026e17 Mon Sep 17 00:00:00 2001 From: Pierre Ossman Date: Tue, 6 Sep 2005 15:18:53 -0700 Subject: [PATCH] sd: SCR register Read the SD specific SCR register from the card. Signed-off-by: Pierre Ossman Cc: Russell King Cc: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/mmc/mmc.c | 143 ++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 133 insertions(+), 10 deletions(-) (limited to 'drivers/mmc/mmc.c') diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 725c6ad3eb6..21d4fb3314f 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -16,6 +16,8 @@ #include #include #include +#include +#include #include #include @@ -246,6 +248,8 @@ int mmc_wait_for_app_cmd(struct mmc_host *host, unsigned int rca, EXPORT_SYMBOL(mmc_wait_for_app_cmd); +static int mmc_select_card(struct mmc_host *host, struct mmc_card *card); + /** * __mmc_claim_host - exclusively claim a host * @host: mmc host to claim @@ -278,16 +282,10 @@ int __mmc_claim_host(struct mmc_host *host, struct mmc_card *card) spin_unlock_irqrestore(&host->lock, flags); remove_wait_queue(&host->wq, &wait); - if (card != (void *)-1 && host->card_selected != card) { - struct mmc_command cmd; - - host->card_selected = card; - - cmd.opcode = MMC_SELECT_CARD; - cmd.arg = card->rca << 16; - cmd.flags = MMC_RSP_R1; - - err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES); + if (card != (void *)-1) { + err = mmc_select_card(host, card); + if (err != MMC_ERR_NONE) + return err; } return err; @@ -317,6 +315,29 @@ void mmc_release_host(struct mmc_host *host) EXPORT_SYMBOL(mmc_release_host); +static int mmc_select_card(struct mmc_host *host, struct mmc_card *card) +{ + int err; + struct mmc_command cmd; + + BUG_ON(host->card_busy == NULL); + + if (host->card_selected == card) + return MMC_ERR_NONE; + + host->card_selected = card; + + cmd.opcode = MMC_SELECT_CARD; + cmd.arg = card->rca << 16; + cmd.flags = MMC_RSP_R1; + + err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES); + if (err != MMC_ERR_NONE) + return err; + + return MMC_ERR_NONE; +} + /* * Ensure that no card is selected. */ @@ -525,6 +546,32 @@ static void mmc_decode_csd(struct mmc_card *card) } } +/* + * Given a 64-bit response, decode to our card SCR structure. + */ +static void mmc_decode_scr(struct mmc_card *card) +{ + struct sd_scr *scr = &card->scr; + unsigned int scr_struct; + u32 resp[4]; + + BUG_ON(!mmc_card_sd(card)); + + resp[3] = card->raw_scr[1]; + resp[2] = card->raw_scr[0]; + + scr_struct = UNSTUFF_BITS(resp, 60, 4); + if (scr_struct != 0) { + printk("%s: unrecognised SCR structure version %d\n", + mmc_hostname(card->host), scr_struct); + mmc_card_set_bad(card); + return; + } + + scr->sda_vsn = UNSTUFF_BITS(resp, 56, 4); + scr->bus_widths = UNSTUFF_BITS(resp, 48, 4); +} + /* * Locate a MMC card on this MMC host given a raw CID. */ @@ -789,6 +836,79 @@ static void mmc_read_csds(struct mmc_host *host) } } +static void mmc_read_scrs(struct mmc_host *host) +{ + int err; + struct mmc_card *card; + + struct mmc_request mrq; + struct mmc_command cmd; + struct mmc_data data; + + struct scatterlist sg; + + list_for_each_entry(card, &host->cards, node) { + if (card->state & (MMC_STATE_DEAD|MMC_STATE_PRESENT)) + continue; + if (!mmc_card_sd(card)) + continue; + + err = mmc_select_card(host, card); + if (err != MMC_ERR_NONE) { + mmc_card_set_dead(card); + continue; + } + + memset(&cmd, 0, sizeof(struct mmc_command)); + + cmd.opcode = MMC_APP_CMD; + cmd.arg = card->rca << 16; + cmd.flags = MMC_RSP_R1; + + err = mmc_wait_for_cmd(host, &cmd, 0); + if ((err != MMC_ERR_NONE) || !(cmd.resp[0] & R1_APP_CMD)) { + mmc_card_set_dead(card); + continue; + } + + memset(&cmd, 0, sizeof(struct mmc_command)); + + cmd.opcode = SD_APP_SEND_SCR; + cmd.arg = 0; + cmd.flags = MMC_RSP_R1; + + memset(&data, 0, sizeof(struct mmc_data)); + + data.timeout_ns = card->csd.tacc_ns * 10; + data.timeout_clks = card->csd.tacc_clks * 10; + data.blksz_bits = 3; + data.blocks = 1; + data.flags = MMC_DATA_READ; + data.sg = &sg; + data.sg_len = 1; + + memset(&mrq, 0, sizeof(struct mmc_request)); + + mrq.cmd = &cmd; + mrq.data = &data; + + sg_init_one(&sg, (u8*)card->raw_scr, 8); + + err = mmc_wait_for_req(host, &mrq); + if (err != MMC_ERR_NONE) { + mmc_card_set_dead(card); + continue; + } + + card->raw_scr[0] = ntohl(card->raw_scr[0]); + card->raw_scr[1] = ntohl(card->raw_scr[1]); + + mmc_decode_scr(card); + } + + mmc_deselect_cards(host); +} + static unsigned int mmc_calculate_clock(struct mmc_host *host) { struct mmc_card *card; @@ -912,6 +1032,9 @@ static void mmc_setup(struct mmc_host *host) host->ops->set_ios(host, &host->ios); mmc_read_csds(host); + + if (host->mode == MMC_MODE_SD) + mmc_read_scrs(host); } -- cgit v1.2.3