上段LINUX的MMC文件

a13736925316

/*
*  linux/drivers/mmc/mmc.c
*
*  Copyright (C) 2003-2004 Russell King, 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/config.h>
#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/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/protocol.h>

#include "mmc.h"

#ifdef CONFIG_MMC_DEBUG
#define DBG(x...)        printk(KERN_DEBUG x)
#else
#define DBG(x...)        do { } while (0)
#endif

#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 command
*        @host: MMC host which completed command
*        @mrq: MMC request which completed
*
*        MMC drivers should call this function when they have completed
*        their processing of a command.  This should be called before the
*        data part of the command has completed.
*/
void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
{
        struct mmc_command *cmd = mrq->cmd;
        int err = mrq->cmd->error;
        DBG("MMC: req done (%02x): %d: %08x %08x %08x %08x\n", cmd->opcode,
            err, 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)
{
        DBG("MMC: starting cmd %02x arg %08x flags %08x\n",
            mrq->cmd->opcode, mrq->cmd->arg, mrq->cmd->flags);

        WARN_ON(host->card_busy == NULL);

        mrq->cmd->error = 0;
        mrq->cmd->mrq = mrq;
        if (mrq->data) {
                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(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->card_busy == NULL);

        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_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.
*/
int __mmc_claim_host(struct mmc_host *host, struct mmc_card *card)
{
        DECLARE_WAITQUEUE(wait, current);
        unsigned long flags;
        int err = 0;

        add_wait_queue(&host->wq, &wait);
        spin_lock_irqsave(&host->lock, flags);
        while (1) {
                set_current_state(TASK_UNINTERRUPTIBLE);
                if (host->card_busy == NULL)
                        break;
                spin_unlock_irqrestore(&host->lock, flags);
                schedule();
                spin_lock_irqsave(&host->lock, flags);
        }
        set_current_state(TASK_RUNNING);
        host->card_busy = 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);
        }

        return err;
}

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->card_busy == NULL);

        spin_lock_irqsave(&host->lock, flags);
        host->card_busy = NULL;
        spin_unlock_irqrestore(&host->lock, flags);

        wake_up(&host->wq);
}

EXPORT_SYMBOL(mmc_release_host);

/*
* Ensure that no card is selected.
*/
static void mmc_deselect_cards(struct mmc_host *host)
{
        struct mmc_command cmd;

        if (host->card_selected) {
                host->card_selected = NULL;

                cmd.opcode = MMC_SELECT_CARD;
                cmd.arg = 0;
                cmd.flags = MMC_RSP_NONE;

                mmc_wait_for_cmd(host, &cmd, 0);
        }
}


static inline void mmc_delay(unsigned int ms)
{
        if (ms < HZ / 1000) {
                yield();
                mdelay(ms);
        } else {
                msleep_interruptible (ms);
        }
}

/*
* 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;
                host->ops->set_ios(host, &host->ios);
        } else {
                ocr = 0;
        }

        return ocr;
}

#define UNSTUFF_BITS(resp,start,size)                                        \
        ({                                                                \
                const u32 __mask = (1 << (size)) - 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);        \
                __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));

        /*
         * The selection of the format here is guesswork based upon
         * information people have sent to date.
         */
        switch (card->csd.mmca_vsn) {
        case 0: /* MMC v1.? */
        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.x ? */
        case 3: /* MMC v3.x ? */
                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",
                        card->host->host_name, 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 v2.
         * v2 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",
                        card->host->host_name, 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);
}

/*
* Locate a MMC card on this MMC host given a raw CID.
*/
static struct mmc_card *mmc_find_card(struct mmc_host *host, u32 *raw_cid)
{
        struct mmc_card *card;

        list_for_each_entry(card, &host->cards, node) {
                if (memcmp(card->raw_cid, raw_cid, sizeof(card->raw_cid)) == 0)
                        return card;
        }
        return NULL;
}

/*
* Allocate a new MMC card, and assign a unique RCA.
*/
static struct mmc_card *
mmc_alloc_card(struct mmc_host *host, u32 *raw_cid, unsigned int *frca)
{
        struct mmc_card *card, *c;
        unsigned int rca = *frca;

        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));

again:
        list_for_each_entry(c, &host->cards, node)
                if (c->rca == rca) {
                        rca++;
                        goto again;
                }

        card->rca = rca;

        *frca = rca;

        return card;
}

/*
* Tell attached cards to go to IDLE state
*/
static void mmc_idle_cards(struct mmc_host *host)
{
        struct mmc_command cmd;

        cmd.opcode = MMC_GO_IDLE_STATE;
        cmd.arg = 0;
        cmd.flags = MMC_RSP_NONE;

        mmc_wait_for_cmd(host, &cmd, 0);

        mmc_delay(1);
}

/*
* Apply power to the MMC stack.
*/
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.power_mode = MMC_POWER_UP;
        host->ops->set_ios(host, &host->ios);

        mmc_delay(1);

        host->ios.clock = host->f_min;
        host->ios.power_mode = MMC_POWER_ON;
        host->ops->set_ios(host, &host->ios);

        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.power_mode = MMC_POWER_OFF;
        host->ops->set_ios(host, &host->ios);
}

static int mmc_send_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
{
        struct mmc_command cmd;
        int i, err = 0;

        cmd.opcode = MMC_SEND_OP_COND;
        cmd.arg = ocr;
        cmd.flags = MMC_RSP_R3;

        for (i = 100; i; i--) {
                err = mmc_wait_for_cmd(host, &cmd, 0);
                if (err != MMC_ERR_NONE)
                        break;

                if (cmd.resp[0] & MMC_CARD_BUSY || ocr == 0)
                        break;

                err = MMC_ERR_TIMEOUT;

                mmc_delay(10);
        }

        if (rocr)
                *rocr = cmd.resp[0];

        return err;
}

/*
* Discover cards by requesting their CID.  If this command
* times out, it is not an error; there are no further cards
* to be discovered.  Add new cards to the list.
*
* Create a mmc_card entry for each discovered card, assigning
* it an RCA, and save the raw CID for decoding later.
*/
static void mmc_discover_cards(struct mmc_host *host)
{
        struct mmc_card *card;
        unsigned int first_rca = 1, err;

        while (1) {
                struct mmc_command cmd;

                cmd.opcode = MMC_ALL_SEND_CID;
                cmd.arg = 0;
                cmd.flags = MMC_RSP_R2;

                err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
                if (err == MMC_ERR_TIMEOUT) {
                        err = MMC_ERR_NONE;
                        break;
                }
                if (err != MMC_ERR_NONE) {
                        printk(KERN_ERR "%s: error requesting CID: %d\n",
                                host->host_name, err);
                        break;
                }

                card = mmc_find_card(host, cmd.resp);
                if (!card) {
                        card = mmc_alloc_card(host, cmd.resp, &first_rca);
                        if (IS_ERR(card)) {
                                err = PTR_ERR(card);
                                break;
                        }
                        list_add(&card->node, &host->cards);
                }

                card->state &= ~MMC_STATE_DEAD;

                cmd.opcode = MMC_SET_RELATIVE_ADDR;
                cmd.arg = card->rca << 16;
                cmd.flags = MMC_RSP_R1;

                err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
                if (err != MMC_ERR_NONE)
                        mmc_card_set_dead(card);
        }
}

static void mmc_read_csds(struct mmc_host *host)
{
        struct mmc_card *card;

        list_for_each_entry(card, &host->cards, node) {
                struct mmc_command cmd;
                int err;

                if (card->state & (MMC_STATE_DEAD|MMC_STATE_PRESENT))
                        continue;

                cmd.opcode = MMC_SEND_CSD;
                cmd.arg = card->rca << 16;
                cmd.flags = MMC_RSP_R2;

                err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
                if (err != MMC_ERR_NONE) {
                        mmc_card_set_dead(card);
                        continue;
                }

                memcpy(card->raw_csd, cmd.resp, sizeof(card->raw_csd));

                mmc_decode_csd(card);
                mmc_decode_cid(card);
        }
}

static unsigned int mmc_calculate_clock(struct mmc_host *host)
{
        struct mmc_card *card;
        unsigned int max_dtr = host->f_max;

        list_for_each_entry(card, &host->cards, node)
                if (!mmc_card_dead(card) && max_dtr > card->csd.max_dtr)
                        max_dtr = card->csd.max_dtr;

        DBG("MMC: selected %d.%03dMHz transfer rate\n",
            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_cards(struct mmc_host *host)
{
        struct list_head *l, *n;

        mmc_deselect_cards(host);

        list_for_each_safe(l, n, &host->cards) {
                struct mmc_card *card = mmc_list_to_card(l);
                struct mmc_command cmd;
                int err;

                cmd.opcode = MMC_SEND_STATUS;
                cmd.arg = card->rca << 16;
                cmd.flags = MMC_RSP_R1;

                err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
                if (err == MMC_ERR_NONE)
                        continue;

                mmc_card_set_dead(card);
        }
}

static void mmc_setup(struct mmc_host *host)
{
        if (host->ios.power_mode != MMC_POWER_ON) {
                int err;
                u32 ocr;

                mmc_power_up(host);
                mmc_idle_cards(host);

                err = mmc_send_op_cond(host, 0, &ocr);
                if (err != MMC_ERR_NONE)
                        return;

                host->ocr = mmc_select_voltage(host, ocr);

                /*
                 * 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.
                 */
                if (host->ocr)
                        mmc_idle_cards(host);
        } else {
                host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
                host->ios.clock = host->f_min;
                host->ops->set_ios(host, &host->ios);

                /*
                 * We should remember the OCR mask from the existing
                 * cards, and detect the new cards OCR mask, combine
                 * the two and re-select the VDD.  However, if we do
                 * change VDD, we should do an idle, and then do a
                 * full re-initialisation.  We would need to notify
                 * drivers so that they can re-setup the cards as
                 * well, while keeping their queues at bay.
                 *
                 * For the moment, we take the easy way out - if the
                 * new cards don't like our currently selected VDD,
                 * they drop off the bus.
                 */
        }

        if (host->ocr == 0)
                return;

        /*
         * 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.)
         */
        mmc_send_op_cond(host, host->ocr, NULL);

        mmc_discover_cards(host);

        /*
         * Ok, now switch to push-pull mode.
         */
        host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
        host->ops->set_ios(host, &host->ios);

        mmc_read_csds(host);
}


/**
*        mmc_detect_change - process change of state on a MMC socket
*        @host: host which changed state.
*
*        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)
{
        schedule_work(&host->detect);
}

EXPORT_SYMBOL(mmc_detect_change);


static void mmc_rescan(void *data)
{
        struct mmc_host *host = data;
        struct list_head *l, *n;

        mmc_claim_host(host);

        if (host->ios.power_mode == MMC_POWER_ON)
                mmc_check_cards(host);

        mmc_setup(host);

        if (!list_empty(&host->cards)) {
                /*
                 * (Re-)calculate the fastest clock rate which the
                 * attached cards and the host support.
                 */
                host->ios.clock = mmc_calculate_clock(host);
                host->ops->set_ios(host, &host->ios);
        }

        mmc_release_host(host);

        list_for_each_safe(l, n, &host->cards) {
                struct mmc_card *card = mmc_list_to_card(l);

                /*
                 * If this is a new and good card, register it.
                 */
                if (!mmc_card_present(card) && !mmc_card_dead(card)) {
                        if (mmc_register_card(card))
                                mmc_card_set_dead(card);
                        else
                                mmc_card_set_present(card);
                }

                /*
                 * If this card is dead, destroy it.
                 */
                if (mmc_card_dead(card)) {
                        list_del(&card->node);
                        mmc_remove_card(card);
                }
        }

        /*
         * If we discover that there are no cards on the
         * bus, turn off the clock and power down.
         */
        if (list_empty(&host->cards))
                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 = kmalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
        if (host) {
                memset(host, 0, sizeof(struct mmc_host) + extra);

                spin_lock_init(&host->lock);
                init_waitqueue_head(&host->wq);
                INIT_LIST_HEAD(&host->cards);
                INIT_WORK(&host->detect, mmc_rescan, host);

                host->dev = dev;

                /*
                 * 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_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
                host->max_seg_size = PAGE_CACHE_SIZE;
        }

        return host;
}

EXPORT_SYMBOL(mmc_alloc_host);

/**
*        mmc_add_host - initialise host hardware
*        @host: mmc host
*/
int mmc_add_host(struct mmc_host *host)
{
        static unsigned int host_num;

        snprintf(host->host_name, sizeof(host->host_name),
                 "mmc%d", host_num++);

        mmc_power_off(host);
        mmc_detect_change(host);

        return 0;
}

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)
{
        struct list_head *l, *n;

        list_for_each_safe(l, n, &host->cards) {
                struct mmc_card *card = mmc_list_to_card(l);

                mmc_remove_card(card);
        }

        mmc_power_off(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)
{
        flush_scheduled_work();
        kfree(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, u32 state)
{
        mmc_claim_host(host);
        mmc_deselect_cards(host);
        mmc_power_off(host);
        mmc_release_host(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_detect_change(host);

        return 0;
}

EXPORT_SYMBOL(mmc_resume_host);

#endif

MODULE_LICENSE("GPL");

a13736925316

/*
*  linux/drivers/mmc/mmc.h
*
*  Copyright (C) 2003 Russell King, 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.
*/
#ifndef _MMC_H
#define _MMC_H
/* core-internal functions */
void mmc_init_card(struct mmc_card *card, struct mmc_host *host);
int mmc_register_card(struct mmc_card *card);
void mmc_remove_card(struct mmc_card *card);
#endif

a13736925316

/*
    eeprom.c - Part of lm_sensors, Linux kernel modules for hardware
               monitoring
    Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl> and
                               Philip Edelbrock <phil@netroedge.com>
    Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
    Copyright (C) 2003 IBM Corp.

    2004-01-16  Jean Delvare <khali@linux-fr.org>
    Divide the eeprom in 32-byte (arbitrary) slices. This significantly
    speeds sensors up, as well as various scripts using the eeprom
    module.

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/i2c.h>
#include <linux/i2c-sensor.h>

/* Addresses to scan */
static unsigned short normal_i2c[] = { 0x50, 0x51, 0x52, 0x53, 0x54,
                                        0x55, 0x56, 0x57, I2C_CLIENT_END };
static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };

/* Insmod parameters */
SENSORS_INSMOD_1(eeprom);

static int checksum = 0;
module_param(checksum, bool, 0);
MODULE_PARM_DESC(checksum, "Only accept eeproms whose checksum is correct");


/* EEPROM registers */
#define EEPROM_REG_CHECKSUM        0x3f

/* Size of EEPROM in bytes */
#define EEPROM_SIZE                256

/* possible types of eeprom devices */
enum eeprom_nature {
        UNKNOWN,
        VAIO,
};

/* Each client has this additional data */
struct eeprom_data {
        struct i2c_client client;
        struct semaphore update_lock;
        u8 valid;                        /* bitfield, bit!=0 if slice is valid */
        unsigned long last_updated[8];        /* In jiffies, 8 slices */
        u8 data[EEPROM_SIZE];                /* Register values */
        enum eeprom_nature nature;
};


static int eeprom_attach_adapter(struct i2c_adapter *adapter);
static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind);
static int eeprom_detach_client(struct i2c_client *client);

/* This is the driver that will be inserted */
static struct i2c_driver eeprom_driver = {
        .owner                = THIS_MODULE,
        .name                = "eeprom",
        .id                = I2C_DRIVERID_EEPROM,
        .flags                = I2C_DF_NOTIFY,
        .attach_adapter        = eeprom_attach_adapter,
        .detach_client        = eeprom_detach_client,
};

static int eeprom_id;

static void eeprom_update_client(struct i2c_client *client, u8 slice)
{
        struct eeprom_data *data = i2c_get_clientdata(client);
        int i, j;

        down(&data->update_lock);

        if (!(data->valid & (1 << slice)) ||
            (jiffies - data->last_updated[slice] > 300 * HZ) ||
            (jiffies < data->last_updated[slice])) {
                dev_dbg(&client->dev, "Starting eeprom update, slice %u\n", slice);

                if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
                        for (i = slice << 5; i < (slice + 1) << 5; i += I2C_SMBUS_I2C_BLOCK_MAX)
                                if (i2c_smbus_read_i2c_block_data(client, i, data->data + i) != I2C_SMBUS_I2C_BLOCK_MAX)
                                        goto exit;
                } else {
                        if (i2c_smbus_write_byte(client, slice << 5)) {
                                dev_dbg(&client->dev, "eeprom read start has failed!\n");
                                goto exit;
                        }
                        for (i = slice << 5; i < (slice + 1) << 5; i++) {
                                j = i2c_smbus_read_byte(client);
                                if (j < 0)
                                        goto exit;
                                data->data = (u8) j;
                        }
                }
                data->last_updated[slice] = jiffies;
                data->valid |= (1 << slice);
        }
exit:
        up(&data->update_lock);
}

static ssize_t eeprom_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
{
        struct i2c_client *client = to_i2c_client(container_of(kobj, struct device, kobj));
        struct eeprom_data *data = i2c_get_clientdata(client);
        u8 slice;

        if (off > EEPROM_SIZE)
                return 0;
        if (off + count > EEPROM_SIZE)
                count = EEPROM_SIZE - off;

        /* Only refresh slices which contain requested bytes */
        for (slice = off >> 5; slice <= (off + count - 1) >> 5; slice++)
                eeprom_update_client(client, slice);

        /* Hide Vaio security settings to regular users (16 first bytes) */
        if (data->nature == VAIO && off < 16 && !capable(CAP_SYS_ADMIN)) {
                int in_row1 = 16 - off;
                memset(buf, 0, in_row1);
                if (count - in_row1 > 0)
                        memcpy(buf + in_row1, &data->data[16], count - in_row1);
        } else {
                memcpy(buf, &data->data[off], count);
        }

        return count;
}

static struct bin_attribute eeprom_attr = {
        .attr = {
                .name = "eeprom",
                .mode = S_IRUGO,
                .owner = THIS_MODULE,
        },
        .size = EEPROM_SIZE,
        .read = eeprom_read,
};

static int eeprom_attach_adapter(struct i2c_adapter *adapter)
{
        return i2c_detect(adapter, &addr_data, eeprom_detect);
}

/* This function is called by i2c_detect */
int eeprom_detect(struct i2c_adapter *adapter, int address, int kind)
{
        int i, cs;
        struct i2c_client *new_client;
        struct eeprom_data *data;
        int err = 0;

        /* Make sure we aren't probing the ISA bus!! This is just a safety check
           at this moment; i2c_detect really won't call us. */
#ifdef DEBUG
        if (i2c_is_isa_adapter(adapter)) {
                dev_dbg(&adapter->dev, " eeprom_detect called for an ISA bus adapter?!?\n");
                return 0;
        }
#endif

        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
                goto exit;

        /* OK. For now, we presume we have a valid client. We now create the
           client structure, even though we cannot fill it completely yet.
           But it allows us to access eeprom_{read,write}_value. */
        if (!(data = kmalloc(sizeof(struct eeprom_data), GFP_KERNEL))) {
                err = -ENOMEM;
                goto exit;
        }
        memset(data, 0, sizeof(struct eeprom_data));

        new_client = &data->client;
        memset(data->data, 0xff, EEPROM_SIZE);
        i2c_set_clientdata(new_client, data);
        new_client->addr = address;
        new_client->adapter = adapter;
        new_client->driver = &eeprom_driver;
        new_client->flags = 0;

        /* prevent 24RF08 corruption */
        i2c_smbus_write_quick(new_client, 0);

        /* Now, we do the remaining detection. It is not there, unless you force
           the checksum to work out. */
        if (checksum) {
                cs = 0;
                for (i = 0; i <= 0x3e; i++)
                        cs += i2c_smbus_read_byte_data(new_client, i);
                cs &= 0xff;
                if (i2c_smbus_read_byte_data (new_client, EEPROM_REG_CHECKSUM) != cs)
                        goto exit_kfree;
        }

        data->nature = UNKNOWN;
        /* Detect the Vaio nature of EEPROMs.
           We use the "PCG-" prefix as the signature. */
        if (address == 0x57) {
                if (i2c_smbus_read_byte_data(new_client, 0x80) == 'P' &&
                    i2c_smbus_read_byte_data(new_client, 0x81) == 'C' &&
                    i2c_smbus_read_byte_data(new_client, 0x82) == 'G' &&
                    i2c_smbus_read_byte_data(new_client, 0x83) == '-')
                        data->nature = VAIO;
        }

        /* Fill in the remaining client fields */
        strncpy(new_client->name, "eeprom", I2C_NAME_SIZE);
        new_client->id = eeprom_id++;
        data->valid = 0;
        init_MUTEX(&data->update_lock);

        /* Tell the I2C layer a new client has arrived */
        if ((err = i2c_attach_client(new_client)))
                goto exit_kfree;

        /* create the sysfs eeprom file */
        sysfs_create_bin_file(&new_client->dev.kobj, &eeprom_attr);

        return 0;

exit_kfree:
        kfree(data);
exit:
        return err;
}

static int eeprom_detach_client(struct i2c_client *client)
{
        int err;

        err = i2c_detach_client(client);
        if (err) {
                dev_err(&client->dev, "Client deregistration failed, client not detached.\n");
                return err;
        }

        kfree(i2c_get_clientdata(client));

        return 0;
}

static int __init eeprom_init(void)
{
        return i2c_add_driver(&eeprom_driver);
}

static void __exit eeprom_exit(void)
{
        i2c_del_driver(&eeprom_driver);
}


MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
                "Philip Edelbrock <phil@netroedge.com> and "
                "Greg Kroah-Hartman <greg@kroah.com>");
MODULE_DESCRIPTION("I2C EEPROM driver");
MODULE_LICENSE("GPL");

module_init(eeprom_init);
module_exit(eeprom_exit);

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