linux/drivers/mmc/core/core.c
Nicolas Pitre 95cdfb72b9 mmc: propagate error codes back from bus drivers' suspend/resume methods
Especially for SDIO drivers which may have special conditions/errors to
report, it is a good thing to relay the returned error code back to upper
layers.

This also allows for the rationalization of the resume path where code to
"remove" a no-longer-existing or replaced card was duplicated into the
MMC, SD and SDIO bus drivers.

In the SDIO case, if a function suspend method returns an error, then all
previously suspended functions are resumed and the error returned.  An
exception is made for -ENOSYS which the core interprets as "we don't
support suspend so just kick the card out for suspend and return success".

When resuming SDIO cards, the core code only validates the manufacturer
and product IDs to make sure the same kind of card is still present before
invoking functions resume methods.  It's the function driver's
responsibility to perform further tests to confirm that the actual same
card is present (same MAC address, etc.) and return an error otherwise.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:38 -07:00

1359 lines
30 KiB
C

/*
* 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) 2005-2008 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 <linux/leds.h>
#include <linux/scatterlist.h>
#include <linux/log2.h>
#include <linux/regulator/consumer.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 "bus.h"
#include "host.h"
#include "sdio_bus.h"
#include "mmc_ops.h"
#include "sd_ops.h"
#include "sdio_ops.h"
static struct workqueue_struct *workqueue;
/*
* Enabling software CRCs on the data blocks can be a significant (30%)
* performance cost, and for other reasons may not always be desired.
* So we allow it it to be disabled.
*/
int use_spi_crc = 1;
module_param(use_spi_crc, bool, 0);
/*
* Internal function. Schedule delayed work in the MMC work queue.
*/
static int mmc_schedule_delayed_work(struct delayed_work *work,
unsigned long delay)
{
return queue_delayed_work(workqueue, work, delay);
}
/*
* Internal function. Flush all scheduled work from the MMC work queue.
*/
static void mmc_flush_scheduled_work(void)
{
flush_workqueue(workqueue);
}
/**
* 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;
if (err && cmd->retries && mmc_host_is_spi(host)) {
if (cmd->resp[0] & R1_SPI_ILLEGAL_COMMAND)
cmd->retries = 0;
}
if (err && cmd->retries) {
pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
mmc_hostname(host), cmd->opcode, err);
cmd->retries--;
cmd->error = 0;
host->ops->request(host, mrq);
} else {
led_trigger_event(host->led, LED_OFF);
pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
mmc_hostname(host), cmd->opcode, err,
cmd->resp[0], cmd->resp[1],
cmd->resp[2], cmd->resp[3]);
if (mrq->data) {
pr_debug("%s: %d bytes transferred: %d\n",
mmc_hostname(host),
mrq->data->bytes_xfered, mrq->data->error);
}
if (mrq->stop) {
pr_debug("%s: (CMD%u): %d: %08x %08x %08x %08x\n",
mmc_hostname(host), mrq->stop->opcode,
mrq->stop->error,
mrq->stop->resp[0], mrq->stop->resp[1],
mrq->stop->resp[2], mrq->stop->resp[3]);
}
if (mrq->done)
mrq->done(mrq);
}
}
EXPORT_SYMBOL(mmc_request_done);
static void
mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
{
#ifdef CONFIG_MMC_DEBUG
unsigned int i, sz;
struct scatterlist *sg;
#endif
pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
mmc_hostname(host), mrq->cmd->opcode,
mrq->cmd->arg, mrq->cmd->flags);
if (mrq->data) {
pr_debug("%s: blksz %d blocks %d flags %08x "
"tsac %d ms nsac %d\n",
mmc_hostname(host), mrq->data->blksz,
mrq->data->blocks, mrq->data->flags,
mrq->data->timeout_ns / 1000000,
mrq->data->timeout_clks);
}
if (mrq->stop) {
pr_debug("%s: CMD%u arg %08x flags %08x\n",
mmc_hostname(host), mrq->stop->opcode,
mrq->stop->arg, mrq->stop->flags);
}
WARN_ON(!host->claimed);
led_trigger_event(host->led, LED_FULL);
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_each_sg(mrq->data->sg, sg, mrq->data->sg_len, i)
sz += sg->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);
}
static void mmc_wait_done(struct mmc_request *mrq)
{
complete(mrq->done_data);
}
/**
* mmc_wait_for_req - start a request and wait for completion
* @host: MMC host to start command
* @mrq: MMC request to start
*
* Start a new MMC custom command request for a host, and wait
* for the command to complete. Does not attempt to parse the
* response.
*/
void 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);
}
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;
WARN_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
*
* Computes the data timeout parameters according to the
* correct algorithm given the card type.
*/
void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card)
{
unsigned int mult;
/*
* SDIO cards only define an upper 1 s limit on access.
*/
if (mmc_card_sdio(card)) {
data->timeout_ns = 1000000000;
data->timeout_clks = 0;
return;
}
/*
* 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 (data->flags & MMC_DATA_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 (data->flags & MMC_DATA_WRITE)
/*
* The limit is really 250 ms, but that is
* insufficient for some crappy cards.
*/
limit_us = 300000;
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;
}
}
/*
* Some cards need very high timeouts if driven in SPI mode.
* The worst observed timeout was 900ms after writing a
* continuous stream of data until the internal logic
* overflowed.
*/
if (mmc_host_is_spi(card->host)) {
if (data->flags & MMC_DATA_WRITE) {
if (data->timeout_ns < 1000000000)
data->timeout_ns = 1000000000; /* 1s */
} else {
if (data->timeout_ns < 100000000)
data->timeout_ns = 100000000; /* 100ms */
}
}
}
EXPORT_SYMBOL(mmc_set_data_timeout);
/**
* mmc_align_data_size - pads a transfer size to a more optimal value
* @card: the MMC card associated with the data transfer
* @sz: original transfer size
*
* Pads the original data size with a number of extra bytes in
* order to avoid controller bugs and/or performance hits
* (e.g. some controllers revert to PIO for certain sizes).
*
* Returns the improved size, which might be unmodified.
*
* Note that this function is only relevant when issuing a
* single scatter gather entry.
*/
unsigned int mmc_align_data_size(struct mmc_card *card, unsigned int sz)
{
/*
* FIXME: We don't have a system for the controller to tell
* the core about its problems yet, so for now we just 32-bit
* align the size.
*/
sz = ((sz + 3) / 4) * 4;
return sz;
}
EXPORT_SYMBOL(mmc_align_data_size);
/**
* mmc_host_enable - enable a host.
* @host: mmc host to enable
*
* Hosts that support power saving can use the 'enable' and 'disable'
* methods to exit and enter power saving states. For more information
* see comments for struct mmc_host_ops.
*/
int mmc_host_enable(struct mmc_host *host)
{
if (!(host->caps & MMC_CAP_DISABLE))
return 0;
if (host->en_dis_recurs)
return 0;
if (host->nesting_cnt++)
return 0;
cancel_delayed_work_sync(&host->disable);
if (host->enabled)
return 0;
if (host->ops->enable) {
int err;
host->en_dis_recurs = 1;
err = host->ops->enable(host);
host->en_dis_recurs = 0;
if (err) {
pr_debug("%s: enable error %d\n",
mmc_hostname(host), err);
return err;
}
}
host->enabled = 1;
return 0;
}
EXPORT_SYMBOL(mmc_host_enable);
static int mmc_host_do_disable(struct mmc_host *host, int lazy)
{
if (host->ops->disable) {
int err;
host->en_dis_recurs = 1;
err = host->ops->disable(host, lazy);
host->en_dis_recurs = 0;
if (err < 0) {
pr_debug("%s: disable error %d\n",
mmc_hostname(host), err);
return err;
}
if (err > 0) {
unsigned long delay = msecs_to_jiffies(err);
mmc_schedule_delayed_work(&host->disable, delay);
}
}
host->enabled = 0;
return 0;
}
/**
* mmc_host_disable - disable a host.
* @host: mmc host to disable
*
* Hosts that support power saving can use the 'enable' and 'disable'
* methods to exit and enter power saving states. For more information
* see comments for struct mmc_host_ops.
*/
int mmc_host_disable(struct mmc_host *host)
{
int err;
if (!(host->caps & MMC_CAP_DISABLE))
return 0;
if (host->en_dis_recurs)
return 0;
if (--host->nesting_cnt)
return 0;
if (!host->enabled)
return 0;
err = mmc_host_do_disable(host, 0);
return err;
}
EXPORT_SYMBOL(mmc_host_disable);
/**
* __mmc_claim_host - exclusively claim a host
* @host: mmc host to claim
* @abort: whether or not the operation should be aborted
*
* Claim a host for a set of operations. If @abort is non null and
* dereference a non-zero value then this will return prematurely with
* that non-zero value without acquiring the lock. Returns zero
* with the lock held otherwise.
*/
int __mmc_claim_host(struct mmc_host *host, atomic_t *abort)
{
DECLARE_WAITQUEUE(wait, current);
unsigned long flags;
int stop;
might_sleep();
add_wait_queue(&host->wq, &wait);
spin_lock_irqsave(&host->lock, flags);
while (1) {
set_current_state(TASK_UNINTERRUPTIBLE);
stop = abort ? atomic_read(abort) : 0;
if (stop || !host->claimed || host->claimer == current)
break;
spin_unlock_irqrestore(&host->lock, flags);
schedule();
spin_lock_irqsave(&host->lock, flags);
}
set_current_state(TASK_RUNNING);
if (!stop) {
host->claimed = 1;
host->claimer = current;
host->claim_cnt += 1;
} else
wake_up(&host->wq);
spin_unlock_irqrestore(&host->lock, flags);
remove_wait_queue(&host->wq, &wait);
if (!stop)
mmc_host_enable(host);
return stop;
}
EXPORT_SYMBOL(__mmc_claim_host);
/**
* mmc_try_claim_host - try exclusively to claim a host
* @host: mmc host to claim
*
* Returns %1 if the host is claimed, %0 otherwise.
*/
int mmc_try_claim_host(struct mmc_host *host)
{
int claimed_host = 0;
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
if (!host->claimed || host->claimer == current) {
host->claimed = 1;
host->claimer = current;
host->claim_cnt += 1;
claimed_host = 1;
}
spin_unlock_irqrestore(&host->lock, flags);
return claimed_host;
}
EXPORT_SYMBOL(mmc_try_claim_host);
static void mmc_do_release_host(struct mmc_host *host)
{
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
if (--host->claim_cnt) {
/* Release for nested claim */
spin_unlock_irqrestore(&host->lock, flags);
} else {
host->claimed = 0;
host->claimer = NULL;
spin_unlock_irqrestore(&host->lock, flags);
wake_up(&host->wq);
}
}
void mmc_host_deeper_disable(struct work_struct *work)
{
struct mmc_host *host =
container_of(work, struct mmc_host, disable.work);
/* If the host is claimed then we do not want to disable it anymore */
if (!mmc_try_claim_host(host))
return;
mmc_host_do_disable(host, 1);
mmc_do_release_host(host);
}
/**
* mmc_host_lazy_disable - lazily disable a host.
* @host: mmc host to disable
*
* Hosts that support power saving can use the 'enable' and 'disable'
* methods to exit and enter power saving states. For more information
* see comments for struct mmc_host_ops.
*/
int mmc_host_lazy_disable(struct mmc_host *host)
{
if (!(host->caps & MMC_CAP_DISABLE))
return 0;
if (host->en_dis_recurs)
return 0;
if (--host->nesting_cnt)
return 0;
if (!host->enabled)
return 0;
if (host->disable_delay) {
mmc_schedule_delayed_work(&host->disable,
msecs_to_jiffies(host->disable_delay));
return 0;
} else
return mmc_host_do_disable(host, 1);
}
EXPORT_SYMBOL(mmc_host_lazy_disable);
/**
* 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)
{
WARN_ON(!host->claimed);
mmc_host_lazy_disable(host);
mmc_do_release_host(host);
}
EXPORT_SYMBOL(mmc_release_host);
/*
* Internal function that does the actual ios call to the host driver,
* optionally printing some debug output.
*/
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);
}
/*
* Control chip select pin on a host.
*/
void mmc_set_chip_select(struct mmc_host *host, int mode)
{
host->ios.chip_select = mode;
mmc_set_ios(host);
}
/*
* Sets the host clock to the highest possible frequency that
* is below "hz".
*/
void mmc_set_clock(struct mmc_host *host, unsigned int hz)
{
WARN_ON(hz < host->f_min);
if (hz > host->f_max)
hz = host->f_max;
host->ios.clock = hz;
mmc_set_ios(host);
}
/*
* Change the bus mode (open drain/push-pull) of a host.
*/
void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
{
host->ios.bus_mode = mode;
mmc_set_ios(host);
}
/*
* Change data bus width of a host.
*/
void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
{
host->ios.bus_width = width;
mmc_set_ios(host);
}
/**
* mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
* @vdd: voltage (mV)
* @low_bits: prefer low bits in boundary cases
*
* This function returns the OCR bit number according to the provided @vdd
* value. If conversion is not possible a negative errno value returned.
*
* Depending on the @low_bits flag the function prefers low or high OCR bits
* on boundary voltages. For example,
* with @low_bits = true, 3300 mV translates to ilog2(MMC_VDD_32_33);
* with @low_bits = false, 3300 mV translates to ilog2(MMC_VDD_33_34);
*
* Any value in the [1951:1999] range translates to the ilog2(MMC_VDD_20_21).
*/
static int mmc_vdd_to_ocrbitnum(int vdd, bool low_bits)
{
const int max_bit = ilog2(MMC_VDD_35_36);
int bit;
if (vdd < 1650 || vdd > 3600)
return -EINVAL;
if (vdd >= 1650 && vdd <= 1950)
return ilog2(MMC_VDD_165_195);
if (low_bits)
vdd -= 1;
/* Base 2000 mV, step 100 mV, bit's base 8. */
bit = (vdd - 2000) / 100 + 8;
if (bit > max_bit)
return max_bit;
return bit;
}
/**
* mmc_vddrange_to_ocrmask - Convert a voltage range to the OCR mask
* @vdd_min: minimum voltage value (mV)
* @vdd_max: maximum voltage value (mV)
*
* This function returns the OCR mask bits according to the provided @vdd_min
* and @vdd_max values. If conversion is not possible the function returns 0.
*
* Notes wrt boundary cases:
* This function sets the OCR bits for all boundary voltages, for example
* [3300:3400] range is translated to MMC_VDD_32_33 | MMC_VDD_33_34 |
* MMC_VDD_34_35 mask.
*/
u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
{
u32 mask = 0;
if (vdd_max < vdd_min)
return 0;
/* Prefer high bits for the boundary vdd_max values. */
vdd_max = mmc_vdd_to_ocrbitnum(vdd_max, false);
if (vdd_max < 0)
return 0;
/* Prefer low bits for the boundary vdd_min values. */
vdd_min = mmc_vdd_to_ocrbitnum(vdd_min, true);
if (vdd_min < 0)
return 0;
/* Fill the mask, from max bit to min bit. */
while (vdd_max >= vdd_min)
mask |= 1 << vdd_max--;
return mask;
}
EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
#ifdef CONFIG_REGULATOR
/**
* mmc_regulator_get_ocrmask - return mask of supported voltages
* @supply: regulator to use
*
* This returns either a negative errno, or a mask of voltages that
* can be provided to MMC/SD/SDIO devices using the specified voltage
* regulator. This would normally be called before registering the
* MMC host adapter.
*/
int mmc_regulator_get_ocrmask(struct regulator *supply)
{
int result = 0;
int count;
int i;
count = regulator_count_voltages(supply);
if (count < 0)
return count;
for (i = 0; i < count; i++) {
int vdd_uV;
int vdd_mV;
vdd_uV = regulator_list_voltage(supply, i);
if (vdd_uV <= 0)
continue;
vdd_mV = vdd_uV / 1000;
result |= mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
}
return result;
}
EXPORT_SYMBOL(mmc_regulator_get_ocrmask);
/**
* mmc_regulator_set_ocr - set regulator to match host->ios voltage
* @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
* @supply: regulator to use
*
* Returns zero on success, else negative errno.
*
* MMC host drivers may use this to enable or disable a regulator using
* a particular supply voltage. This would normally be called from the
* set_ios() method.
*/
int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit)
{
int result = 0;
int min_uV, max_uV;
int enabled;
enabled = regulator_is_enabled(supply);
if (enabled < 0)
return enabled;
if (vdd_bit) {
int tmp;
int voltage;
/* REVISIT mmc_vddrange_to_ocrmask() may have set some
* bits this regulator doesn't quite support ... don't
* be too picky, most cards and regulators are OK with
* a 0.1V range goof (it's a small error percentage).
*/
tmp = vdd_bit - ilog2(MMC_VDD_165_195);
if (tmp == 0) {
min_uV = 1650 * 1000;
max_uV = 1950 * 1000;
} else {
min_uV = 1900 * 1000 + tmp * 100 * 1000;
max_uV = min_uV + 100 * 1000;
}
/* avoid needless changes to this voltage; the regulator
* might not allow this operation
*/
voltage = regulator_get_voltage(supply);
if (voltage < 0)
result = voltage;
else if (voltage < min_uV || voltage > max_uV)
result = regulator_set_voltage(supply, min_uV, max_uV);
else
result = 0;
if (result == 0 && !enabled)
result = regulator_enable(supply);
} else if (enabled) {
result = regulator_disable(supply);
}
return result;
}
EXPORT_SYMBOL(mmc_regulator_set_ocr);
#endif
/*
* Mask off any voltages we don't support and select
* the lowest voltage
*/
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 {
pr_warning("%s: host doesn't support card's voltages\n",
mmc_hostname(host));
ocr = 0;
}
return ocr;
}
/*
* Select timing parameters for host.
*/
void mmc_set_timing(struct mmc_host *host, unsigned int timing)
{
host->ios.timing = timing;
mmc_set_ios(host);
}
/*
* 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;
/* If ocr is set, we use it */
if (host->ocr)
bit = ffs(host->ocr) - 1;
else
bit = fls(host->ocr_avail) - 1;
host->ios.vdd = bit;
if (mmc_host_is_spi(host)) {
host->ios.chip_select = MMC_CS_HIGH;
host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
} else {
host->ios.chip_select = MMC_CS_DONTCARE;
host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
}
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);
/*
* This delay should be sufficient to allow the power supply
* to reach the minimum voltage.
*/
mmc_delay(10);
if (host->f_min > 400000) {
pr_warning("%s: Minimum clock frequency too high for "
"identification mode\n", mmc_hostname(host));
host->ios.clock = host->f_min;
} else
host->ios.clock = 400000;
host->ios.power_mode = MMC_POWER_ON;
mmc_set_ios(host);
/*
* This delay must be at least 74 clock sizes, or 1 ms, or the
* time required to reach a stable voltage.
*/
mmc_delay(10);
}
static void mmc_power_off(struct mmc_host *host)
{
host->ios.clock = 0;
host->ios.vdd = 0;
if (!mmc_host_is_spi(host)) {
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);
}
/*
* Cleanup when the last reference to the bus operator is dropped.
*/
static void __mmc_release_bus(struct mmc_host *host)
{
BUG_ON(!host);
BUG_ON(host->bus_refs);
BUG_ON(!host->bus_dead);
host->bus_ops = NULL;
}
/*
* Increase reference count of bus operator
*/
static inline void mmc_bus_get(struct mmc_host *host)
{
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
host->bus_refs++;
spin_unlock_irqrestore(&host->lock, flags);
}
/*
* Decrease reference count of bus operator and free it if
* it is the last reference.
*/
static inline void mmc_bus_put(struct mmc_host *host)
{
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
host->bus_refs--;
if ((host->bus_refs == 0) && host->bus_ops)
__mmc_release_bus(host);
spin_unlock_irqrestore(&host->lock, flags);
}
/*
* Assign a mmc bus handler to a host. Only one bus handler may control a
* host at any given time.
*/
void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
{
unsigned long flags;
BUG_ON(!host);
BUG_ON(!ops);
WARN_ON(!host->claimed);
spin_lock_irqsave(&host->lock, flags);
BUG_ON(host->bus_ops);
BUG_ON(host->bus_refs);
host->bus_ops = ops;
host->bus_refs = 1;
host->bus_dead = 0;
spin_unlock_irqrestore(&host->lock, flags);
}
/*
* Remove the current bus handler from a host. Assumes that there are
* no interesting cards left, so the bus is powered down.
*/
void mmc_detach_bus(struct mmc_host *host)
{
unsigned long flags;
BUG_ON(!host);
WARN_ON(!host->claimed);
WARN_ON(!host->bus_ops);
spin_lock_irqsave(&host->lock, flags);
host->bus_dead = 1;
spin_unlock_irqrestore(&host->lock, flags);
mmc_power_off(host);
mmc_bus_put(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)
*
* MMC drivers should call this when they detect a card has been
* inserted or removed. The MMC layer will confirm that any
* present card is still functional, and initialize any newly
* inserted.
*/
void mmc_detect_change(struct mmc_host *host, unsigned long delay)
{
#ifdef CONFIG_MMC_DEBUG
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
WARN_ON(host->removed);
spin_unlock_irqrestore(&host->lock, flags);
#endif
mmc_schedule_delayed_work(&host->detect, delay);
}
EXPORT_SYMBOL(mmc_detect_change);
void mmc_rescan(struct work_struct *work)
{
struct mmc_host *host =
container_of(work, struct mmc_host, detect.work);
u32 ocr;
int err;
mmc_bus_get(host);
/* if there is a card registered, check whether it is still present */
if ((host->bus_ops != NULL) && host->bus_ops->detect && !host->bus_dead)
host->bus_ops->detect(host);
mmc_bus_put(host);
mmc_bus_get(host);
/* if there still is a card present, stop here */
if (host->bus_ops != NULL) {
mmc_bus_put(host);
goto out;
}
/* detect a newly inserted card */
/*
* Only we can add a new handler, so it's safe to
* release the lock here.
*/
mmc_bus_put(host);
if (host->ops->get_cd && host->ops->get_cd(host) == 0)
goto out;
mmc_claim_host(host);
mmc_power_up(host);
mmc_go_idle(host);
mmc_send_if_cond(host, host->ocr_avail);
/*
* First we search for SDIO...
*/
err = mmc_send_io_op_cond(host, 0, &ocr);
if (!err) {
if (mmc_attach_sdio(host, ocr))
mmc_power_off(host);
goto out;
}
/*
* ...then normal SD...
*/
err = mmc_send_app_op_cond(host, 0, &ocr);
if (!err) {
if (mmc_attach_sd(host, ocr))
mmc_power_off(host);
goto out;
}
/*
* ...and finally MMC.
*/
err = mmc_send_op_cond(host, 0, &ocr);
if (!err) {
if (mmc_attach_mmc(host, ocr))
mmc_power_off(host);
goto out;
}
mmc_release_host(host);
mmc_power_off(host);
out:
if (host->caps & MMC_CAP_NEEDS_POLL)
mmc_schedule_delayed_work(&host->detect, HZ);
}
void mmc_start_host(struct mmc_host *host)
{
mmc_power_off(host);
mmc_detect_change(host, 0);
}
void mmc_stop_host(struct mmc_host *host)
{
#ifdef CONFIG_MMC_DEBUG
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
host->removed = 1;
spin_unlock_irqrestore(&host->lock, flags);
#endif
if (host->caps & MMC_CAP_DISABLE)
cancel_delayed_work(&host->disable);
cancel_delayed_work(&host->detect);
mmc_flush_scheduled_work();
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead) {
if (host->bus_ops->remove)
host->bus_ops->remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
mmc_bus_put(host);
return;
}
mmc_bus_put(host);
BUG_ON(host->card);
mmc_power_off(host);
}
void mmc_power_save_host(struct mmc_host *host)
{
mmc_bus_get(host);
if (!host->bus_ops || host->bus_dead || !host->bus_ops->power_restore) {
mmc_bus_put(host);
return;
}
if (host->bus_ops->power_save)
host->bus_ops->power_save(host);
mmc_bus_put(host);
mmc_power_off(host);
}
EXPORT_SYMBOL(mmc_power_save_host);
void mmc_power_restore_host(struct mmc_host *host)
{
mmc_bus_get(host);
if (!host->bus_ops || host->bus_dead || !host->bus_ops->power_restore) {
mmc_bus_put(host);
return;
}
mmc_power_up(host);
host->bus_ops->power_restore(host);
mmc_bus_put(host);
}
EXPORT_SYMBOL(mmc_power_restore_host);
int mmc_card_awake(struct mmc_host *host)
{
int err = -ENOSYS;
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead && host->bus_ops->awake)
err = host->bus_ops->awake(host);
mmc_bus_put(host);
return err;
}
EXPORT_SYMBOL(mmc_card_awake);
int mmc_card_sleep(struct mmc_host *host)
{
int err = -ENOSYS;
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead && host->bus_ops->awake)
err = host->bus_ops->sleep(host);
mmc_bus_put(host);
return err;
}
EXPORT_SYMBOL(mmc_card_sleep);
int mmc_card_can_sleep(struct mmc_host *host)
{
struct mmc_card *card = host->card;
if (card && mmc_card_mmc(card) && card->ext_csd.rev >= 3)
return 1;
return 0;
}
EXPORT_SYMBOL(mmc_card_can_sleep);
#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)
{
int err = 0;
if (host->caps & MMC_CAP_DISABLE)
cancel_delayed_work(&host->disable);
cancel_delayed_work(&host->detect);
mmc_flush_scheduled_work();
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead) {
if (host->bus_ops->suspend)
err = host->bus_ops->suspend(host);
if (err == -ENOSYS || !host->bus_ops->resume) {
/*
* We simply "remove" the card in this case.
* It will be redetected on resume.
*/
if (host->bus_ops->remove)
host->bus_ops->remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
err = 0;
}
}
mmc_bus_put(host);
if (!err)
mmc_power_off(host);
return err;
}
EXPORT_SYMBOL(mmc_suspend_host);
/**
* mmc_resume_host - resume a previously suspended host
* @host: mmc host
*/
int mmc_resume_host(struct mmc_host *host)
{
int err = 0;
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead) {
mmc_power_up(host);
mmc_select_voltage(host, host->ocr);
BUG_ON(!host->bus_ops->resume);
err = host->bus_ops->resume(host);
if (err) {
printk(KERN_WARNING "%s: error %d during resume "
"(card was removed?)\n",
mmc_hostname(host), err);
if (host->bus_ops->remove)
host->bus_ops->remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
/* no need to bother upper layers */
err = 0;
}
}
mmc_bus_put(host);
/*
* We add a slight delay here so that resume can progress
* in parallel.
*/
mmc_detect_change(host, 1);
return err;
}
EXPORT_SYMBOL(mmc_resume_host);
#endif
static int __init mmc_init(void)
{
int ret;
workqueue = create_singlethread_workqueue("kmmcd");
if (!workqueue)
return -ENOMEM;
ret = mmc_register_bus();
if (ret)
goto destroy_workqueue;
ret = mmc_register_host_class();
if (ret)
goto unregister_bus;
ret = sdio_register_bus();
if (ret)
goto unregister_host_class;
return 0;
unregister_host_class:
mmc_unregister_host_class();
unregister_bus:
mmc_unregister_bus();
destroy_workqueue:
destroy_workqueue(workqueue);
return ret;
}
static void __exit mmc_exit(void)
{
sdio_unregister_bus();
mmc_unregister_host_class();
mmc_unregister_bus();
destroy_workqueue(workqueue);
}
subsys_initcall(mmc_init);
module_exit(mmc_exit);
MODULE_LICENSE("GPL");