diff options
Diffstat (limited to 'drivers/mmc/core/mmc.c')
| -rw-r--r-- | drivers/mmc/core/mmc.c | 430 |
1 files changed, 430 insertions, 0 deletions
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c new file mode 100644 index 00000000000..c528017d612 --- /dev/null +++ b/drivers/mmc/core/mmc.c @@ -0,0 +1,430 @@ +/* + * linux/drivers/mmc/mmc.c + * + * Copyright (C) 2003-2004 Russell King, All Rights Reserved. + * Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved. + * MMCv4 support Copyright (C) 2006 Philip Langdale, 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" + +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; + + /* + * The selection of the format here is based upon published + * specs from sandisk and from what people have reported. + */ + switch (card->csd.mmca_vsn) { + case 0: /* MMC v1.0 - v1.2 */ + case 1: /* MMC v1.4 */ + card->cid.manfid = UNSTUFF_BITS(resp, 104, 24); + 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.prod_name[5] = UNSTUFF_BITS(resp, 56, 8); + card->cid.prod_name[6] = UNSTUFF_BITS(resp, 48, 8); + card->cid.hwrev = UNSTUFF_BITS(resp, 44, 4); + card->cid.fwrev = UNSTUFF_BITS(resp, 40, 4); + card->cid.serial = UNSTUFF_BITS(resp, 16, 24); + card->cid.month = UNSTUFF_BITS(resp, 12, 4); + card->cid.year = UNSTUFF_BITS(resp, 8, 4) + 1997; + break; + + case 2: /* MMC v2.0 - v2.2 */ + case 3: /* MMC v3.1 - v3.3 */ + case 4: /* MMC v4 */ + 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.prod_name[5] = UNSTUFF_BITS(resp, 56, 8); + card->cid.serial = UNSTUFF_BITS(resp, 16, 32); + card->cid.month = UNSTUFF_BITS(resp, 12, 4); + card->cid.year = UNSTUFF_BITS(resp, 8, 4) + 1997; + break; + + default: + printk("%s: card has unknown MMCA version %d\n", + mmc_hostname(card->host), card->csd.mmca_vsn); + mmc_card_set_bad(card); + break; + } +} + +/* + * 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; + + /* + * We only understand CSD structure v1.1 and v1.2. + * v1.2 has extra information in bits 15, 11 and 10. + */ + csd_struct = UNSTUFF_BITS(resp, 126, 2); + if (csd_struct != 1 && csd_struct != 2) { + printk("%s: unrecognised CSD structure version %d\n", + mmc_hostname(card->host), csd_struct); + mmc_card_set_bad(card); + return; + } + + csd->mmca_vsn = UNSTUFF_BITS(resp, 122, 4); + 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); +} + +/* + * Read and decode extended CSD. Switch to high-speed and wide bus + * if supported. + */ +static int mmc_process_ext_csd(struct mmc_card *card) +{ + int err; + u8 *ext_csd; + + BUG_ON(!card); + + err = MMC_ERR_FAILED; + + if (card->csd.mmca_vsn < CSD_SPEC_VER_4) + return MMC_ERR_NONE; + + /* + * As the ext_csd is so large and mostly unused, we don't store the + * raw block in mmc_card. + */ + ext_csd = kmalloc(512, GFP_KERNEL); + if (!ext_csd) { + printk(KERN_ERR "%s: could not allocate a buffer to " + "receive the ext_csd. mmc v4 cards will be " + "treated as v3.\n", mmc_hostname(card->host)); + return MMC_ERR_FAILED; + } + + err = mmc_send_ext_csd(card, ext_csd); + if (err != MMC_ERR_NONE) { + /* + * High capacity cards should have this "magic" size + * stored in their CSD. + */ + if (card->csd.capacity == (4096 * 512)) { + printk(KERN_ERR "%s: unable to read EXT_CSD " + "on a possible high capacity card. " + "Card will be ignored.\n", + mmc_hostname(card->host)); + } else { + printk(KERN_WARNING "%s: unable to read " + "EXT_CSD, performance might " + "suffer.\n", + mmc_hostname(card->host)); + err = MMC_ERR_NONE; + } + goto out; + } + + card->ext_csd.sectors = + ext_csd[EXT_CSD_SEC_CNT + 0] << 0 | + ext_csd[EXT_CSD_SEC_CNT + 1] << 8 | + ext_csd[EXT_CSD_SEC_CNT + 2] << 16 | + ext_csd[EXT_CSD_SEC_CNT + 3] << 24; + if (card->ext_csd.sectors) + mmc_card_set_blockaddr(card); + + switch (ext_csd[EXT_CSD_CARD_TYPE]) { + case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26: + card->ext_csd.hs_max_dtr = 52000000; + break; + case EXT_CSD_CARD_TYPE_26: + card->ext_csd.hs_max_dtr = 26000000; + break; + default: + /* MMC v4 spec says this cannot happen */ + printk(KERN_WARNING "%s: card is mmc v4 but doesn't " + "support any high-speed modes.\n", + mmc_hostname(card->host)); + goto out; + } + + if (card->host->caps & MMC_CAP_MMC_HIGHSPEED) { + /* Activate highspeed support. */ + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_HS_TIMING, 1); + if (err != MMC_ERR_NONE) { + printk(KERN_WARNING "%s: failed to switch " + "card to mmc v4 high-speed mode.\n", + mmc_hostname(card->host)); + err = MMC_ERR_NONE; + goto out; + } + + mmc_card_set_highspeed(card); + + mmc_set_timing(card->host, MMC_TIMING_MMC_HS); + } + + /* Check for host support for wide-bus modes. */ + if (card->host->caps & MMC_CAP_4_BIT_DATA) { + /* Activate 4-bit support. */ + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_BUS_WIDTH, EXT_CSD_BUS_WIDTH_4); + if (err != MMC_ERR_NONE) { + printk(KERN_WARNING "%s: failed to switch " + "card to mmc v4 4-bit bus mode.\n", + mmc_hostname(card->host)); + err = MMC_ERR_NONE; + goto out; + } + + mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4); + } + +out: + kfree(ext_csd); + + return err; +} + +/* + * Host is being removed. Free up the current card. + */ +static void mmc_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_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_ops = { + .remove = mmc_remove, + .detect = mmc_detect, +}; + +/* + * Starting point for MMC card init. + */ +int mmc_attach_mmc(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_ops); + + host->ocr = mmc_select_voltage(host, ocr); + + /* + * Can we support the voltage of the card? + */ + 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); + + /* The extra bit indicates that we support high capacity */ + mmc_send_op_cond(host, host->ocr | (1 << 30), 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_MMC; + card->rca = 1; + memcpy(card->raw_cid, cid, sizeof(card->raw_cid)); + + /* + * Set card RCA. + */ + err = mmc_set_relative_addr(card); + 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 and process extened CSD. + * This will switch into high-speed and wide bus modes, + * as available. + */ + err = mmc_select_card(card); + if (err != MMC_ERR_NONE) + goto free_card; + + err = mmc_process_ext_csd(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->ext_csd.hs_max_dtr) + max_dtr = card->ext_csd.hs_max_dtr; + } else if (max_dtr > card->csd.max_dtr) { + max_dtr = card->csd.max_dtr; + } + + mmc_set_clock(host, max_dtr); + + 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; +} + |