Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-05 03:21:32 +00:00
Code Issues Packages Projects Releases Wiki Activity
da7fbe58d2
linux/drivers/mmc/core/core.c
Pierre Ossman da7fbe58d2 mmc: Separate out protocol ops 
Move protocol operations and definitions into their own files
in an effort to separate protocol handling and bus
arbitration more clearly.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-05-01 13:04:18 +02:00

1256 lines
29 KiB
C
Raw Blame History

/*
* linux/drivers/mmc/core/core.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.
* 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/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/pagemap.h>
#include <linux/err.h>
#include <asm/scatterlist.h>
#include <linux/scatterlist.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sd.h>
#include "core.h"
#include "sysfs.h"
#include "mmc_ops.h"
#include "sd_ops.h"
#define CMD_RETRIES 3
/*
* OCR Bit positions to 10s of Vdd mV.
*/
static const unsigned short mmc_ocr_bit_to_vdd[] = {
150, 155, 160, 165, 170, 180, 190, 200,
210, 220, 230, 240, 250, 260, 270, 280,
290, 300, 310, 320, 330, 340, 350, 360
};
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,
};
/**
* mmc_request_done - finish processing an MMC request
* @host: MMC host which completed request
* @mrq: MMC request which request
*
* MMC drivers should call this function when they have completed
* their processing of a request.
*/
void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
{
struct mmc_command *cmd = mrq->cmd;
int err = cmd->error;
pr_debug("%s: req done (CMD%u): %d/%d/%d: %08x %08x %08x %08x\n",
mmc_hostname(host), cmd->opcode, err,
mrq->data ? mrq->data->error : 0,
mrq->stop ? mrq->stop->error : 0,
cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3]);
if (err && cmd->retries) {
cmd->retries--;
cmd->error = 0;
host->ops->request(host, mrq);
} else if (mrq->done) {
mrq->done(mrq);
}
}
EXPORT_SYMBOL(mmc_request_done);
/**
* mmc_start_request - start a command on a host
* @host: MMC host to start command on
* @mrq: MMC request to start
*
* Queue a command on the specified host. We expect the
* caller to be holding the host lock with interrupts disabled.
*/
void
mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
{
#ifdef CONFIG_MMC_DEBUG
unsigned int i, sz;
#endif
pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
mmc_hostname(host), mrq->cmd->opcode,
mrq->cmd->arg, mrq->cmd->flags);
WARN_ON(!host->claimed);
mrq->cmd->error = 0;
mrq->cmd->mrq = mrq;
if (mrq->data) {
BUG_ON(mrq->data->blksz > host->max_blk_size);
BUG_ON(mrq->data->blocks > host->max_blk_count);
BUG_ON(mrq->data->blocks * mrq->data->blksz >
host->max_req_size);
#ifdef CONFIG_MMC_DEBUG
sz = 0;
for (i = 0;i < mrq->data->sg_len;i++)
sz += mrq->data->sg[i].length;
BUG_ON(sz != mrq->data->blocks * mrq->data->blksz);
#endif
mrq->cmd->data = mrq->data;
mrq->data->error = 0;
mrq->data->mrq = mrq;
if (mrq->stop) {
mrq->data->stop = mrq->stop;
mrq->stop->error = 0;
mrq->stop->mrq = mrq;
}
}
host->ops->request(host, mrq);
}
EXPORT_SYMBOL(mmc_start_request);
static void mmc_wait_done(struct mmc_request *mrq)
{
complete(mrq->done_data);
}
int mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
{
DECLARE_COMPLETION_ONSTACK(complete);
mrq->done_data = &complete;
mrq->done = mmc_wait_done;
mmc_start_request(host, mrq);
wait_for_completion(&complete);
return 0;
}
EXPORT_SYMBOL(mmc_wait_for_req);
/**
* mmc_wait_for_cmd - start a command and wait for completion
* @host: MMC host to start command
* @cmd: MMC command to start
* @retries: maximum number of retries
*
* Start a new MMC command for a host, and wait for the command
* to complete. Return any error that occurred while the command
* was executing. Do not attempt to parse the response.
*/
int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
{
struct mmc_request mrq;
BUG_ON(!host->claimed);
memset(&mrq, 0, sizeof(struct mmc_request));
memset(cmd->resp, 0, sizeof(cmd->resp));
cmd->retries = retries;
mrq.cmd = cmd;
cmd->data = NULL;
mmc_wait_for_req(host, &mrq);
return cmd->error;
}
EXPORT_SYMBOL(mmc_wait_for_cmd);
/**
* mmc_set_data_timeout - set the timeout for a data command
* @data: data phase for command
* @card: the MMC card associated with the data transfer
* @write: flag to differentiate reads from writes
*/
void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card,
int write)
{
unsigned int mult;
/*
* SD cards use a 100 multiplier rather than 10
*/
mult = mmc_card_sd(card) ? 100 : 10;
/*
* Scale up the multiplier (and therefore the timeout) by
* the r2w factor for writes.
*/
if (write)
mult <<= card->csd.r2w_factor;
data->timeout_ns = card->csd.tacc_ns * mult;
data->timeout_clks = card->csd.tacc_clks * mult;
/*
* SD cards also have an upper limit on the timeout.
*/
if (mmc_card_sd(card)) {
unsigned int timeout_us, limit_us;
timeout_us = data->timeout_ns / 1000;
timeout_us += data->timeout_clks * 1000 /
(card->host->ios.clock / 1000);
if (write)
limit_us = 250000;
else
limit_us = 100000;
/*
* SDHC cards always use these fixed values.
*/
if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
data->timeout_ns = limit_us * 1000;
data->timeout_clks = 0;
}
}
}
EXPORT_SYMBOL(mmc_set_data_timeout);
/**
* __mmc_claim_host - exclusively claim a host
* @host: mmc host to claim
* @card: mmc card to claim host for
*
* Claim a host for a set of operations. If a valid card
* is passed and this wasn't the last card selected, select
* the card before returning.
*
* Note: you should use mmc_card_claim_host or mmc_claim_host.
*/
void mmc_claim_host(struct mmc_host *host)
{
DECLARE_WAITQUEUE(wait, current);
unsigned long flags;
add_wait_queue(&host->wq, &wait);
spin_lock_irqsave(&host->lock, flags);
while (1) {
set_current_state(TASK_UNINTERRUPTIBLE);
if (!host->claimed)
break;
spin_unlock_irqrestore(&host->lock, flags);
schedule();
spin_lock_irqsave(&host->lock, flags);
}
set_current_state(TASK_RUNNING);
host->claimed = 1;
spin_unlock_irqrestore(&host->lock, flags);
remove_wait_queue(&host->wq, &wait);
}
EXPORT_SYMBOL(mmc_claim_host);
/**
* mmc_release_host - release a host
* @host: mmc host to release
*
* Release a MMC host, allowing others to claim the host
* for their operations.
*/
void mmc_release_host(struct mmc_host *host)
{
unsigned long flags;
BUG_ON(!host->claimed);
spin_lock_irqsave(&host->lock, flags);
host->claimed = 0;
spin_unlock_irqrestore(&host->lock, flags);
wake_up(&host->wq);
}
EXPORT_SYMBOL(mmc_release_host);
static inline void mmc_set_ios(struct mmc_host *host)
{
struct mmc_ios *ios = &host->ios;
pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
"width %u timing %u\n",
mmc_hostname(host), ios->clock, ios->bus_mode,
ios->power_mode, ios->chip_select, ios->vdd,
ios->bus_width, ios->timing);
host->ops->set_ios(host, ios);
}
void mmc_set_chip_select(struct mmc_host *host, int mode)
{
host->ios.chip_select = mode;
mmc_set_ios(host);
}
/*
* Mask off any voltages we don't support and select
* the lowest voltage
*/
static u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
{
int bit;
ocr &= host->ocr_avail;
bit = ffs(ocr);
if (bit) {
bit -= 1;
ocr &= 3 << bit;
host->ios.vdd = bit;
mmc_set_ios(host);
} else {
ocr = 0;
}
return ocr;
}
#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));
if (mmc_card_sd(card)) {
/*
* 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 */
} else {
/*
* 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;
if (mmc_card_sd(card)) {
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;
}
} else {
/*
* 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);
}
}
/*
* 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);
}
/*
* Allocate a new MMC card
*/
static struct mmc_card *
mmc_alloc_card(struct mmc_host *host, u32 *raw_cid)
{
struct mmc_card *card;
card = kmalloc(sizeof(struct mmc_card), GFP_KERNEL);
if (!card)
return ERR_PTR(-ENOMEM);
mmc_init_card(card, host);
memcpy(card->raw_cid, raw_cid, sizeof(card->raw_cid));
return card;
}
/*
* Apply power to the MMC stack. This is a two-stage process.
* First, we enable power to the card without the clock running.
* We then wait a bit for the power to stabilise. Finally,
* enable the bus drivers and clock to the card.
*
* We must _NOT_ enable the clock prior to power stablising.
*
* If a host does all the power sequencing itself, ignore the
* initial MMC_POWER_UP stage.
*/
static void mmc_power_up(struct mmc_host *host)
{
int bit = fls(host->ocr_avail) - 1;
host->ios.vdd = bit;
host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
host->ios.chip_select = MMC_CS_DONTCARE;
host->ios.power_mode = MMC_POWER_UP;
host->ios.bus_width = MMC_BUS_WIDTH_1;
host->ios.timing = MMC_TIMING_LEGACY;
mmc_set_ios(host);
mmc_delay(1);
host->ios.clock = host->f_min;
host->ios.power_mode = MMC_POWER_ON;
mmc_set_ios(host);
mmc_delay(2);
}
static void mmc_power_off(struct mmc_host *host)
{
host->ios.clock = 0;
host->ios.vdd = 0;
host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
host->ios.chip_select = MMC_CS_DONTCARE;
host->ios.power_mode = MMC_POWER_OFF;
host->ios.bus_width = MMC_BUS_WIDTH_1;
host->ios.timing = MMC_TIMING_LEGACY;
mmc_set_ios(host);
}
/*
* Discover the card by requesting its CID.
*
* Create a mmc_card entry for the discovered card, assigning
* it an RCA, and save the raw CID for decoding later.
*/
static void mmc_discover_card(struct mmc_host *host)
{
unsigned int err;
u32 cid[4];
BUG_ON(host->card);
err = mmc_all_send_cid(host, cid);
if (err != MMC_ERR_NONE) {
printk(KERN_ERR "%s: error requesting CID: %d\n",
mmc_hostname(host), err);
return;
}
host->card = mmc_alloc_card(host, cid);
if (IS_ERR(host->card)) {
err = PTR_ERR(host->card);
host->card = NULL;
return;
}
if (host->mode == MMC_MODE_SD) {
host->card->type = MMC_TYPE_SD;
err = mmc_send_relative_addr(host, &host->card->rca);
if (err != MMC_ERR_NONE)
mmc_card_set_dead(host->card);
else {
if (!host->ops->get_ro) {
printk(KERN_WARNING "%s: host does not "
"support reading read-only "
"switch. assuming write-enable.\n",
mmc_hostname(host));
} else {
if (host->ops->get_ro(host))
mmc_card_set_readonly(host->card);
}
}
} else {
host->card->type = MMC_TYPE_MMC;
host->card->rca = 1;
err = mmc_set_relative_addr(host->card);
if (err != MMC_ERR_NONE)
mmc_card_set_dead(host->card);
}
}
static void mmc_read_csd(struct mmc_host *host)
{
int err;
if (!host->card)
return;
if (mmc_card_dead(host->card))
return;
err = mmc_send_csd(host->card, host->card->raw_csd);
if (err != MMC_ERR_NONE) {
mmc_card_set_dead(host->card);
return;
}
mmc_decode_csd(host->card);
mmc_decode_cid(host->card);
}
static void mmc_process_ext_csd(struct mmc_host *host)
{
int err;
u8 *ext_csd;
if (!host->card)
return;
if (mmc_card_dead(host->card))
return;
if (mmc_card_sd(host->card))
return;
if (host->card->csd.mmca_vsn < CSD_SPEC_VER_4)
return;
/*
* 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("%s: could not allocate a buffer to receive the ext_csd."
"mmc v4 cards will be treated as v3.\n",
mmc_hostname(host));
return;
}
err = mmc_send_ext_csd(host->card, ext_csd);
if (err != MMC_ERR_NONE) {
if (host->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(host));
mmc_card_set_dead(host->card);
} else {
printk(KERN_WARNING "%s: unable to read "
"EXT_CSD, performance might "
"suffer.\n",
mmc_hostname(host));
}
goto out;
}
host->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 (host->card->ext_csd.sectors)
mmc_card_set_blockaddr(host->card);
switch (ext_csd[EXT_CSD_CARD_TYPE]) {
case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26:
host->card->ext_csd.hs_max_dtr = 52000000;
break;
case EXT_CSD_CARD_TYPE_26:
host->card->ext_csd.hs_max_dtr = 26000000;
break;
default:
/* MMC v4 spec says this cannot happen */
printk("%s: card is mmc v4 but doesn't support "
"any high-speed modes.\n",
mmc_hostname(host));
goto out;
}
if (host->caps & MMC_CAP_MMC_HIGHSPEED) {
/* Activate highspeed support. */
err = mmc_switch(host->card, MMC_SWITCH_MODE_WRITE_BYTE,
EXT_CSD_HS_TIMING, 1);
if (err != MMC_ERR_NONE) {
printk("%s: failed to switch card to mmc v4 "
"high-speed mode.\n",
mmc_hostname(host));
goto out;
}
mmc_card_set_highspeed(host->card);
host->ios.timing = MMC_TIMING_MMC_HS;
mmc_set_ios(host);
}
/* Check for host support for wide-bus modes. */
if (host->caps & MMC_CAP_4_BIT_DATA) {
/* Activate 4-bit support. */
err = mmc_switch(host->card, MMC_SWITCH_MODE_WRITE_BYTE,
EXT_CSD_BUS_WIDTH, EXT_CSD_BUS_WIDTH_4 |
EXT_CSD_CMD_SET_NORMAL);
if (err != MMC_ERR_NONE) {
printk("%s: failed to switch card to "
"mmc v4 4-bit bus mode.\n",
mmc_hostname(host));
goto out;
}
host->ios.bus_width = MMC_BUS_WIDTH_4;
mmc_set_ios(host);
}
out:
kfree(ext_csd);
}
static void mmc_read_scr(struct mmc_host *host)
{
int err;
if (!host->card)
return;
if (mmc_card_dead(host->card))
return;
if (!mmc_card_sd(host->card))
return;
err = mmc_app_send_scr(host->card, host->card->raw_scr);
if (err != MMC_ERR_NONE) {
mmc_card_set_dead(host->card);
return;
}
mmc_decode_scr(host->card);
}
static void mmc_read_switch_caps(struct mmc_host *host)
{
int err;
unsigned char *status;
if (!(host->caps & MMC_CAP_SD_HIGHSPEED))
return;
if (!host->card)
return;
if (mmc_card_dead(host->card))
return;
if (!mmc_card_sd(host->card))
return;
if (host->card->scr.sda_vsn < SCR_SPEC_VER_1)
return;
status = kmalloc(64, GFP_KERNEL);
if (!status) {
printk(KERN_WARNING "%s: Unable to allocate buffer for "
"reading switch capabilities.\n",
mmc_hostname(host));
return;
}
err = mmc_sd_switch(host->card, SD_SWITCH_CHECK,
SD_SWITCH_GRP_ACCESS, SD_SWITCH_ACCESS_HS, status);
if (err != MMC_ERR_NONE) {
printk("%s: unable to read switch capabilities, "
"performance might suffer.\n",
mmc_hostname(host));
goto out;
}
if (status[13] & 0x02)
host->card->sw_caps.hs_max_dtr = 50000000;
err = mmc_sd_switch(host->card, SD_SWITCH_SET,
SD_SWITCH_GRP_ACCESS, SD_SWITCH_ACCESS_HS, status);
if (err != MMC_ERR_NONE || (status[16] & 0xF) != 1) {
printk(KERN_WARNING "%s: Problem switching card "
"into high-speed mode!\n",
mmc_hostname(host));
goto out;
}
mmc_card_set_highspeed(host->card);
host->ios.timing = MMC_TIMING_SD_HS;
mmc_set_ios(host);
out:
kfree(status);
}
static unsigned int mmc_calculate_clock(struct mmc_host *host)
{
unsigned int max_dtr = host->f_max;
if (host->card && !mmc_card_dead(host->card)) {
if (mmc_card_highspeed(host->card) && mmc_card_sd(host->card)) {
if (max_dtr > host->card->sw_caps.hs_max_dtr)
max_dtr = host->card->sw_caps.hs_max_dtr;
} else if (mmc_card_highspeed(host->card) && !mmc_card_sd(host->card)) {
if (max_dtr > host->card->ext_csd.hs_max_dtr)
max_dtr = host->card->ext_csd.hs_max_dtr;
} else if (max_dtr > host->card->csd.max_dtr) {
max_dtr = host->card->csd.max_dtr;
}
}
pr_debug("%s: selected %d.%03dMHz transfer rate\n",
mmc_hostname(host),
max_dtr / 1000000, (max_dtr / 1000) % 1000);
return max_dtr;
}
/*
* Check whether cards we already know about are still present.
* We do this by requesting status, and checking whether a card
* responds.
*
* A request for status does not cause a state change in data
* transfer mode.
*/
static void mmc_check_card(struct mmc_card *card)
{
int err;
BUG_ON(!card);
err = mmc_send_status(card, NULL);
if (err == MMC_ERR_NONE)
return;
mmc_card_set_dead(card);
}
static void mmc_setup(struct mmc_host *host)
{
int err;
u32 ocr;
host->mode = MMC_MODE_SD;
mmc_power_up(host);
mmc_go_idle(host);
err = mmc_send_if_cond(host, host->ocr_avail);
if (err != MMC_ERR_NONE) {
return;
}
err = mmc_send_app_op_cond(host, 0, &ocr);
/*
* If we fail to detect any SD cards then try
* searching for MMC cards.
*/
if (err != MMC_ERR_NONE) {
host->mode = MMC_MODE_MMC;
err = mmc_send_op_cond(host, 0, &ocr);
if (err != MMC_ERR_NONE)
return;
}
host->ocr = mmc_select_voltage(host, ocr);
if (host->ocr == 0)
return;
/*
* 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);
/*
* Send the selected OCR multiple times... until the cards
* all get the idea that they should be ready for CMD2.
* (My SanDisk card seems to need this.)
*/
if (host->mode == MMC_MODE_SD) {
/*
* 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);
} else {
/* The extra bit indicates that we support high capacity */
mmc_send_op_cond(host, host->ocr | (1 << 30), NULL);
}
mmc_discover_card(host);
/*
* Ok, now switch to push-pull mode.
*/
host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
mmc_set_ios(host);
mmc_read_csd(host);
if (host->card && !mmc_card_dead(host->card)) {
err = mmc_select_card(host->card);
if (err != MMC_ERR_NONE)
mmc_card_set_dead(host->card);
}
/*
* The card is in 1 bit mode by default so
* we only need to change if it supports the
* wider version.
*/
if (host->card && !mmc_card_dead(host->card) &&
mmc_card_sd(host->card) &&
(host->card->scr.bus_widths & SD_SCR_BUS_WIDTH_4) &&
(host->card->host->caps & MMC_CAP_4_BIT_DATA)) {
err = mmc_app_set_bus_width(host->card, SD_BUS_WIDTH_4);
if (err != MMC_ERR_NONE)
mmc_card_set_dead(host->card);
else {
host->ios.bus_width = MMC_BUS_WIDTH_4;
mmc_set_ios(host);
}
}
if (host->mode == MMC_MODE_SD) {
mmc_read_scr(host);
mmc_read_switch_caps(host);
} else
mmc_process_ext_csd(host);
}
/**
* mmc_detect_change - process change of state on a MMC socket
* @host: host which changed state.
* @delay: optional delay to wait before detection (jiffies)
*
* All we know is that card(s) have been inserted or removed
* from the socket(s). We don't know which socket or cards.
*/
void mmc_detect_change(struct mmc_host *host, unsigned long delay)
{
#ifdef CONFIG_MMC_DEBUG
mmc_claim_host(host);
BUG_ON(host->removed);
mmc_release_host(host);
#endif
mmc_schedule_delayed_work(&host->detect, delay);
}
EXPORT_SYMBOL(mmc_detect_change);
static void mmc_rescan(struct work_struct *work)
{
struct mmc_host *host =
container_of(work, struct mmc_host, detect.work);
mmc_claim_host(host);
/*
* Check for removed card and newly inserted ones. We check for
* removed cards first so we can intelligently re-select the VDD.
*/
if (host->card) {
mmc_check_card(host->card);
mmc_release_host(host);
if (mmc_card_dead(host->card)) {
mmc_remove_card(host->card);
host->card = NULL;
}
goto out;
}
mmc_setup(host);
if (host->card && !mmc_card_dead(host->card)) {
/*
* (Re-)calculate the fastest clock rate which the
* attached cards and the host support.
*/
host->ios.clock = mmc_calculate_clock(host);
mmc_set_ios(host);
}
mmc_release_host(host);
/*
* If this is a new and good card, register it.
*/
if (host->card && !mmc_card_dead(host->card)) {
if (mmc_register_card(host->card))
mmc_card_set_dead(host->card);
}
/*
* If this card is dead, destroy it.
*/
if (host->card && mmc_card_dead(host->card)) {
mmc_remove_card(host->card);
host->card = NULL;
}
out:
/*
* If we discover that there are no cards on the
* bus, turn off the clock and power down.
*/
if (!host->card)
mmc_power_off(host);
}
/**
* mmc_alloc_host - initialise the per-host structure.
* @extra: sizeof private data structure
* @dev: pointer to host device model structure
*
* Initialise the per-host structure.
*/
struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
{
struct mmc_host *host;
host = mmc_alloc_host_sysfs(extra, dev);
if (host) {
spin_lock_init(&host->lock);
init_waitqueue_head(&host->wq);
INIT_DELAYED_WORK(&host->detect, mmc_rescan);
/*
* By default, hosts do not support SGIO or large requests.
* They have to set these according to their abilities.
*/
host->max_hw_segs = 1;
host->max_phys_segs = 1;
host->max_seg_size = PAGE_CACHE_SIZE;
host->max_req_size = PAGE_CACHE_SIZE;
host->max_blk_size = 512;
host->max_blk_count = PAGE_CACHE_SIZE / 512;
}
return host;
}
EXPORT_SYMBOL(mmc_alloc_host);
/**
* mmc_add_host - initialise host hardware
* @host: mmc host
*/
int mmc_add_host(struct mmc_host *host)
{
int ret;
ret = mmc_add_host_sysfs(host);
if (ret == 0) {
mmc_power_off(host);
mmc_detect_change(host, 0);
}
return ret;
}
EXPORT_SYMBOL(mmc_add_host);
/**
* mmc_remove_host - remove host hardware
* @host: mmc host
*
* Unregister and remove all cards associated with this host,
* and power down the MMC bus.
*/
void mmc_remove_host(struct mmc_host *host)
{
#ifdef CONFIG_MMC_DEBUG
mmc_claim_host(host);
host->removed = 1;
mmc_release_host(host);
#endif
mmc_flush_scheduled_work();
if (host->card) {
mmc_remove_card(host->card);
host->card = NULL;
}
mmc_power_off(host);
mmc_remove_host_sysfs(host);
}
EXPORT_SYMBOL(mmc_remove_host);
/**
* mmc_free_host - free the host structure
* @host: mmc host
*
* Free the host once all references to it have been dropped.
*/
void mmc_free_host(struct mmc_host *host)
{
mmc_free_host_sysfs(host);
}
EXPORT_SYMBOL(mmc_free_host);
#ifdef CONFIG_PM
/**
* mmc_suspend_host - suspend a host
* @host: mmc host
* @state: suspend mode (PM_SUSPEND_xxx)
*/
int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
{
mmc_flush_scheduled_work();
if (host->card) {
mmc_remove_card(host->card);
host->card = NULL;
}
mmc_power_off(host);
return 0;
}
EXPORT_SYMBOL(mmc_suspend_host);
/**
* mmc_resume_host - resume a previously suspended host
* @host: mmc host
*/
int mmc_resume_host(struct mmc_host *host)
{
mmc_rescan(&host->detect.work);
return 0;
}
EXPORT_SYMBOL(mmc_resume_host);
#endif
MODULE_LICENSE("GPL");
Reference in New Issue View Git Blame Copy Permalink