diff options
Diffstat (limited to 'drivers/mmc/core/sd.c')
| -rw-r--r-- | drivers/mmc/core/sd.c | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c new file mode 100644 index 000000000000..6c6beb48f3a8 --- /dev/null +++ b/drivers/mmc/core/sd.c @@ -0,0 +1,431 @@ +/* + * linux/drivers/mmc/sd.c + * + * Copyright (C) 2003-2004 Russell King, All Rights Reserved. + * SD support Copyright (C) 2004 Ian Molton, All Rights Reserved. + * Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/err.h> + +#include <linux/mmc/host.h> +#include <linux/mmc/card.h> +#include <linux/mmc/mmc.h> + +#include "core.h" +#include "sysfs.h" +#include "mmc_ops.h" +#include "sd_ops.h" + +#include "core.h" + +static const unsigned int tran_exp[] = { + 10000, 100000, 1000000, 10000000, + 0, 0, 0, 0 +}; + +static const unsigned char tran_mant[] = { + 0, 10, 12, 13, 15, 20, 25, 30, + 35, 40, 45, 50, 55, 60, 70, 80, +}; + +static const unsigned int tacc_exp[] = { + 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, +}; + +static const unsigned int tacc_mant[] = { + 0, 10, 12, 13, 15, 20, 25, 30, + 35, 40, 45, 50, 55, 60, 70, 80, +}; + +#define UNSTUFF_BITS(resp,start,size) \ + ({ \ + const int __size = size; \ + const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \ + const int __off = 3 - ((start) / 32); \ + const int __shft = (start) & 31; \ + u32 __res; \ + \ + __res = resp[__off] >> __shft; \ + if (__size + __shft > 32) \ + __res |= resp[__off-1] << ((32 - __shft) % 32); \ + __res & __mask; \ + }) + +/* + * Given the decoded CSD structure, decode the raw CID to our CID structure. + */ +static void mmc_decode_cid(struct mmc_card *card) +{ + u32 *resp = card->raw_cid; + + memset(&card->cid, 0, sizeof(struct mmc_cid)); + + /* + * SD doesn't currently have a version field so we will + * have to assume we can parse this. + */ + card->cid.manfid = UNSTUFF_BITS(resp, 120, 8); + card->cid.oemid = UNSTUFF_BITS(resp, 104, 16); + card->cid.prod_name[0] = UNSTUFF_BITS(resp, 96, 8); + card->cid.prod_name[1] = UNSTUFF_BITS(resp, 88, 8); + card->cid.prod_name[2] = UNSTUFF_BITS(resp, 80, 8); + card->cid.prod_name[3] = UNSTUFF_BITS(resp, 72, 8); + card->cid.prod_name[4] = UNSTUFF_BITS(resp, 64, 8); + card->cid.hwrev = UNSTUFF_BITS(resp, 60, 4); + card->cid.fwrev = UNSTUFF_BITS(resp, 56, 4); + card->cid.serial = UNSTUFF_BITS(resp, 24, 32); + card->cid.year = UNSTUFF_BITS(resp, 12, 8); + card->cid.month = UNSTUFF_BITS(resp, 8, 4); + + card->cid.year += 2000; /* SD cards year offset */ +} + +/* + * Given a 128-bit response, decode to our card CSD structure. + */ +static void mmc_decode_csd(struct mmc_card *card) +{ + struct mmc_csd *csd = &card->csd; + unsigned int e, m, csd_struct; + u32 *resp = card->raw_csd; + + csd_struct = UNSTUFF_BITS(resp, 126, 2); + + switch (csd_struct) { + case 0: + m = UNSTUFF_BITS(resp, 115, 4); + e = UNSTUFF_BITS(resp, 112, 3); + csd->tacc_ns = (tacc_exp[e] * tacc_mant[m] + 9) / 10; + csd->tacc_clks = UNSTUFF_BITS(resp, 104, 8) * 100; + + m = UNSTUFF_BITS(resp, 99, 4); + e = UNSTUFF_BITS(resp, 96, 3); + csd->max_dtr = tran_exp[e] * tran_mant[m]; + csd->cmdclass = UNSTUFF_BITS(resp, 84, 12); + + e = UNSTUFF_BITS(resp, 47, 3); + m = UNSTUFF_BITS(resp, 62, 12); + csd->capacity = (1 + m) << (e + 2); + + csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4); + csd->read_partial = UNSTUFF_BITS(resp, 79, 1); + csd->write_misalign = UNSTUFF_BITS(resp, 78, 1); + csd->read_misalign = UNSTUFF_BITS(resp, 77, 1); + csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3); + csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4); + csd->write_partial = UNSTUFF_BITS(resp, 21, 1); + break; + case 1: + /* + * This is a block-addressed SDHC card. Most + * interesting fields are unused and have fixed + * values. To avoid getting tripped by buggy cards, + * we assume those fixed values ourselves. + */ + mmc_card_set_blockaddr(card); + + csd->tacc_ns = 0; /* Unused */ + csd->tacc_clks = 0; /* Unused */ + + m = UNSTUFF_BITS(resp, 99, 4); + e = UNSTUFF_BITS(resp, 96, 3); + csd->max_dtr = tran_exp[e] * tran_mant[m]; + csd->cmdclass = UNSTUFF_BITS(resp, 84, 12); + + m = UNSTUFF_BITS(resp, 48, 22); + csd->capacity = (1 + m) << 10; + + csd->read_blkbits = 9; + csd->read_partial = 0; + csd->write_misalign = 0; + csd->read_misalign = 0; + csd->r2w_factor = 4; /* Unused */ + csd->write_blkbits = 9; + csd->write_partial = 0; + break; + default: + printk("%s: unrecognised CSD structure version %d\n", + mmc_hostname(card->host), csd_struct); + mmc_card_set_bad(card); + return; + } +} + +/* + * 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); +} + +/* + * Test if the card supports high-speed mode and, if so, switch to it. + */ +static int mmc_switch_hs(struct mmc_card *card) +{ + int err; + u8 *status; + + if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED)) + return MMC_ERR_NONE; + + err = MMC_ERR_FAILED; + + status = kmalloc(64, GFP_KERNEL); + if (!status) { + printk("%s: could not allocate a buffer for switch " + "capabilities.\n", + mmc_hostname(card->host)); + return err; + } + + err = mmc_sd_switch(card, 0, 0, 1, status); + if (err != MMC_ERR_NONE) { + /* + * Card not supporting high-speed will ignore the + * command. + */ + if (err == MMC_ERR_TIMEOUT) + err = MMC_ERR_NONE; + goto out; + } + + if (status[13] & 0x02) + card->sw_caps.hs_max_dtr = 50000000; + + err = mmc_sd_switch(card, 1, 0, 1, status); + if (err != MMC_ERR_NONE) + goto out; + + if ((status[16] & 0xF) != 1) { + printk(KERN_WARNING "%s: Problem switching card " + "into high-speed mode!\n", + mmc_hostname(card->host)); + } else { + mmc_card_set_highspeed(card); + mmc_set_timing(card->host, MMC_TIMING_SD_HS); + } + +out: + kfree(status); + + return err; +} + +/* + * Host is being removed. Free up the current card. + */ +static void mmc_sd_remove(struct mmc_host *host) +{ + BUG_ON(!host); + BUG_ON(!host->card); + + mmc_remove_card(host->card); + host->card = NULL; +} + +/* + * Card detection callback from host. + */ +static void mmc_sd_detect(struct mmc_host *host) +{ + int err; + + BUG_ON(!host); + BUG_ON(!host->card); + + mmc_claim_host(host); + + /* + * Just check if our card has been removed. + */ + err = mmc_send_status(host->card, NULL); + + mmc_release_host(host); + + if (err != MMC_ERR_NONE) { + mmc_remove_card(host->card); + host->card = NULL; + + mmc_claim_host(host); + mmc_detach_bus(host); + mmc_release_host(host); + } +} + +static const struct mmc_bus_ops mmc_sd_ops = { + .remove = mmc_sd_remove, + .detect = mmc_sd_detect, +}; + +/* + * Starting point for SD card init. + */ +int mmc_attach_sd(struct mmc_host *host, u32 ocr) +{ + struct mmc_card *card; + int err; + u32 cid[4]; + unsigned int max_dtr; + + BUG_ON(!host); + BUG_ON(!host->claimed); + + mmc_attach_bus(host, &mmc_sd_ops); + + host->ocr = mmc_select_voltage(host, ocr); + + /* + * Can we support the voltage(s) of the card(s)? + */ + if (!host->ocr) + goto err; + + /* + * Since we're changing the OCR value, we seem to + * need to tell some cards to go back to the idle + * state. We wait 1ms to give cards time to + * respond. + */ + mmc_go_idle(host); + + /* + * If SD_SEND_IF_COND indicates an SD 2.0 + * compliant card and we should set bit 30 + * of the ocr to indicate that we can handle + * block-addressed SDHC cards. + */ + err = mmc_send_if_cond(host, host->ocr); + if (err == MMC_ERR_NONE) + ocr = host->ocr | (1 << 30); + + mmc_send_app_op_cond(host, ocr, NULL); + + /* + * Fetch CID from card. + */ + err = mmc_all_send_cid(host, cid); + if (err != MMC_ERR_NONE) + goto err; + + /* + * Allocate card structure. + */ + card = mmc_alloc_card(host); + if (IS_ERR(card)) + goto err; + + card->type = MMC_TYPE_SD; + memcpy(card->raw_cid, cid, sizeof(card->raw_cid)); + + /* + * Set card RCA. + */ + err = mmc_send_relative_addr(host, &card->rca); + if (err != MMC_ERR_NONE) + goto free_card; + + mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL); + + /* + * Fetch CSD from card. + */ + err = mmc_send_csd(card, card->raw_csd); + if (err != MMC_ERR_NONE) + goto free_card; + + mmc_decode_csd(card); + mmc_decode_cid(card); + + /* + * Fetch SCR from card. + */ + err = mmc_select_card(card); + if (err != MMC_ERR_NONE) + goto free_card; + + err = mmc_app_send_scr(card, card->raw_scr); + if (err != MMC_ERR_NONE) + goto free_card; + + mmc_decode_scr(card); + + /* + * Check if card can be switched into high-speed mode. + */ + err = mmc_switch_hs(card); + if (err != MMC_ERR_NONE) + goto free_card; + + /* + * Compute bus speed. + */ + max_dtr = (unsigned int)-1; + + if (mmc_card_highspeed(card)) { + if (max_dtr > card->sw_caps.hs_max_dtr) + max_dtr = card->sw_caps.hs_max_dtr; + } else if (max_dtr > card->csd.max_dtr) { + max_dtr = card->csd.max_dtr; + } + + mmc_set_clock(host, max_dtr); + + /* + * Switch to wider bus (if supported). + */ + if ((host->caps && MMC_CAP_4_BIT_DATA) && + (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) { + err = mmc_app_set_bus_width(card, MMC_BUS_WIDTH_4); + if (err != MMC_ERR_NONE) + goto free_card; + + mmc_set_bus_width(host, MMC_BUS_WIDTH_4); + } + + host->card = card; + + mmc_release_host(host); + + err = mmc_register_card(card); + if (err) + goto reclaim_host; + + return 0; + +reclaim_host: + mmc_claim_host(host); +free_card: + mmc_remove_card(card); + host->card = NULL; +err: + mmc_detach_bus(host); + mmc_release_host(host); + + return 0; +} + |