bus.c

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/*
 *  linux/drivers/mmc/core/bus.c
 *
 *  Copyright (C) 2003 Russell King, All Rights Reserved.
 *  Copyright (C) 2007 Pierre Ossman
 *
 * 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.
 *
 *  MMC card bus driver model
 */

#include <linux/export.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/pm_runtime.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>

#include "core.h"
#include "sdio_cis.h"
#include "bus.h"

#define to_mmc_driver(d)    container_of(d, struct mmc_driver, drv)

static ssize_t mmc_type_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{
    struct mmc_card *card = mmc_dev_to_card(dev);

    switch (card->type) {
    case MMC_TYPE_MMC:
        return sprintf(buf, "MMC\n");
    case MMC_TYPE_SD:
        return sprintf(buf, "SD\n");
    case MMC_TYPE_SDIO:
        return sprintf(buf, "SDIO\n");
    case MMC_TYPE_SD_COMBO:
        return sprintf(buf, "SDcombo\n");
    default:
        return -EFAULT;
    }
}

static struct device_attribute mmc_dev_attrs[] = {
    __ATTR(type, S_IRUGO, mmc_type_show, NULL),
    __ATTR_NULL,
};

/*
 * This currently matches any MMC driver to any MMC card - drivers
 * themselves make the decision whether to drive this card in their
 * probe method.
 */
static int mmc_bus_match(struct device *dev, struct device_driver *drv)
{
    return 1;
}

static int
mmc_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
{
    struct mmc_card *card = mmc_dev_to_card(dev);
    const char *type;
    int retval = 0;

    switch (card->type) {
    case MMC_TYPE_MMC:
        type = "MMC";
        break;
    case MMC_TYPE_SD:
        type = "SD";
        break;
    case MMC_TYPE_SDIO:
        type = "SDIO";
        break;
    case MMC_TYPE_SD_COMBO:
        type = "SDcombo";
        break;
    default:
        type = NULL;
    }

    if (type) {
        retval = add_uevent_var(env, "MMC_TYPE=%s", type);
        if (retval)
            return retval;
    }

    retval = add_uevent_var(env, "MMC_NAME=%s", mmc_card_name(card));
    if (retval)
        return retval;

    /*
     * Request the mmc_block device.  Note: that this is a direct request
     * for the module it carries no information as to what is inserted.
     */
    retval = add_uevent_var(env, "MODALIAS=mmc:block");

    return retval;
}

static int mmc_bus_probe(struct device *dev)
{
    struct mmc_driver *drv = to_mmc_driver(dev->driver);
    struct mmc_card *card = mmc_dev_to_card(dev);

    return drv->probe(card);
}

static int mmc_bus_remove(struct device *dev)
{
    struct mmc_driver *drv = to_mmc_driver(dev->driver);
    struct mmc_card *card = mmc_dev_to_card(dev);

    drv->remove(card);

    return 0;
}

#ifdef CONFIG_PM_SLEEP
static int mmc_bus_suspend(struct device *dev)
{
    struct mmc_driver *drv = to_mmc_driver(dev->driver);
    struct mmc_card *card = mmc_dev_to_card(dev);
    int ret = 0;

    if (dev->driver && drv->suspend)
        ret = drv->suspend(card);
    return ret;
}

static int mmc_bus_resume(struct device *dev)
{
    struct mmc_driver *drv = to_mmc_driver(dev->driver);
    struct mmc_card *card = mmc_dev_to_card(dev);
    int ret = 0;

    if (dev->driver && drv->resume)
        ret = drv->resume(card);
    return ret;
}
#endif

#ifdef CONFIG_PM_RUNTIME

static int mmc_runtime_suspend(struct device *dev)
{
    struct mmc_card *card = mmc_dev_to_card(dev);

    return mmc_power_save_host(card->host);
}

static int mmc_runtime_resume(struct device *dev)
{
    struct mmc_card *card = mmc_dev_to_card(dev);

    return mmc_power_restore_host(card->host);
}

static int mmc_runtime_idle(struct device *dev)
{
    return pm_runtime_suspend(dev);
}

#endif /* !CONFIG_PM_RUNTIME */

static const struct dev_pm_ops mmc_bus_pm_ops = {
    SET_RUNTIME_PM_OPS(mmc_runtime_suspend, mmc_runtime_resume,
            mmc_runtime_idle)
    SET_SYSTEM_SLEEP_PM_OPS(mmc_bus_suspend, mmc_bus_resume)
};

static struct bus_type mmc_bus_type = {
    .name       = "mmc",
    .dev_attrs  = mmc_dev_attrs,
    .match      = mmc_bus_match,
    .uevent     = mmc_bus_uevent,
    .probe      = mmc_bus_probe,
    .remove     = mmc_bus_remove,
    .pm     = &mmc_bus_pm_ops,
};

int mmc_register_bus(void)
{
    return bus_register(&mmc_bus_type);
}

void mmc_unregister_bus(void)
{
    bus_unregister(&mmc_bus_type);
}

int mmc_register_driver(struct mmc_driver *drv)
{
    drv->drv.bus = &mmc_bus_type;
    return driver_register(&drv->drv);
}

EXPORT_SYMBOL(mmc_register_driver);

void mmc_unregister_driver(struct mmc_driver *drv)
{
    drv->drv.bus = &mmc_bus_type;
    driver_unregister(&drv->drv);
}

EXPORT_SYMBOL(mmc_unregister_driver);

static void mmc_release_card(struct device *dev)
{
    struct mmc_card *card = mmc_dev_to_card(dev);

    sdio_free_common_cis(card);

    if (card->info)
        kfree(card->info);

    kfree(card);
}

/*
 * Allocate and initialise a new MMC card structure.
 */
struct mmc_card *mmc_alloc_card(struct mmc_host *host, struct device_type *type)
{
    struct mmc_card *card;

    card = kzalloc(sizeof(struct mmc_card), GFP_KERNEL);
    if (!card)
        return ERR_PTR(-ENOMEM);

    card->host = host;

    device_initialize(&card->dev);

    card->dev.parent = mmc_classdev(host);
    card->dev.bus = &mmc_bus_type;
    card->dev.release = mmc_release_card;
    card->dev.type = type;

    return card;
}

/*
 * Register a new MMC card with the driver model.
 */
int mmc_add_card(struct mmc_card *card)
{
    int ret;
    const char *type;
    const char *uhs_bus_speed_mode = "";
    static const char *const uhs_speeds[] = {
        [UHS_SDR12_BUS_SPEED] = "SDR12 ",
        [UHS_SDR25_BUS_SPEED] = "SDR25 ",
        [UHS_SDR50_BUS_SPEED] = "SDR50 ",
        [UHS_SDR104_BUS_SPEED] = "SDR104 ",
        [UHS_DDR50_BUS_SPEED] = "DDR50 ",
    };


    dev_set_name(&card->dev, "%s:%04x", mmc_hostname(card->host), card->rca);

    switch (card->type) {
    case MMC_TYPE_MMC:
        type = "MMC";
        break;
    case MMC_TYPE_SD:
        type = "SD";
        if (mmc_card_blockaddr(card)) {
            if (mmc_card_ext_capacity(card))
                type = "SDXC";
            else
                type = "SDHC";
        }
        break;
    case MMC_TYPE_SDIO:
        type = "SDIO";
        break;
    case MMC_TYPE_SD_COMBO:
        type = "SD-combo";
        if (mmc_card_blockaddr(card))
            type = "SDHC-combo";
        break;
    default:
        type = "?";
        break;
    }

    if (mmc_sd_card_uhs(card) &&
        (card->sd_bus_speed < ARRAY_SIZE(uhs_speeds)))
        uhs_bus_speed_mode = uhs_speeds[card->sd_bus_speed];

    if (mmc_host_is_spi(card->host)) {
        pr_info("%s: new %s%s%s card on SPI\n",
            mmc_hostname(card->host),
            mmc_card_highspeed(card) ? "high speed " : "",
            mmc_card_ddr_mode(card) ? "DDR " : "",
            type);
    } else {
        pr_info("%s: new %s%s%s%s%s card at address %04x\n",
            mmc_hostname(card->host),
            mmc_card_uhs(card) ? "ultra high speed " :
            (mmc_card_highspeed(card) ? "high speed " : ""),
            (mmc_card_hs200(card) ? "HS200 " : ""),
            mmc_card_ddr_mode(card) ? "DDR " : "",
            uhs_bus_speed_mode, type, card->rca);
    }

#ifdef CONFIG_DEBUG_FS
    mmc_add_card_debugfs(card);
#endif

    ret = device_add(&card->dev);
    if (ret)
        return ret;

    mmc_card_set_present(card);

    return 0;
}

/*
 * Unregister a new MMC card with the driver model, and
 * (eventually) free it.
 */
void mmc_remove_card(struct mmc_card *card)
{
#ifdef CONFIG_DEBUG_FS
    mmc_remove_card_debugfs(card);
#endif

    if (mmc_card_present(card)) {
        if (mmc_host_is_spi(card->host)) {
            pr_info("%s: SPI card removed\n",
                mmc_hostname(card->host));
        } else {
            pr_info("%s: card %04x removed\n",
                mmc_hostname(card->host), card->rca);
        }
        device_del(&card->dev);
    }

    put_device(&card->dev);
}