sdio_bus.c

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/*
 *  linux/drivers/mmc/core/sdio_bus.c
 *
 *  Copyright 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 as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * SDIO function driver model
 */

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

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

#include "sdio_cis.h"
#include "sdio_bus.h"

/* show configuration fields */
#define sdio_config_attr(field, format_string)              \
static ssize_t                              \
field##_show(struct device *dev, struct device_attribute *attr, char *buf)              \
{                                   \
    struct sdio_func *func;                     \
                                    \
    func = dev_to_sdio_func (dev);                  \
    return sprintf (buf, format_string, func->field);       \
}

sdio_config_attr(class, "0x%02x\n");
sdio_config_attr(vendor, "0x%04x\n");
sdio_config_attr(device, "0x%04x\n");

static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct sdio_func *func = dev_to_sdio_func (dev);

    return sprintf(buf, "sdio:c%02Xv%04Xd%04X\n",
            func->class, func->vendor, func->device);
}

static struct device_attribute sdio_dev_attrs[] = {
    __ATTR_RO(class),
    __ATTR_RO(vendor),
    __ATTR_RO(device),
    __ATTR_RO(modalias),
    __ATTR_NULL,
};

static const struct sdio_device_id *sdio_match_one(struct sdio_func *func,
    const struct sdio_device_id *id)
{
    if (id->class != (__u8)SDIO_ANY_ID && id->class != func->class)
        return NULL;
    if (id->vendor != (__u16)SDIO_ANY_ID && id->vendor != func->vendor)
        return NULL;
    if (id->device != (__u16)SDIO_ANY_ID && id->device != func->device)
        return NULL;
    return id;
}

static const struct sdio_device_id *sdio_match_device(struct sdio_func *func,
    struct sdio_driver *sdrv)
{
    const struct sdio_device_id *ids;

    ids = sdrv->id_table;

    if (ids) {
        while (ids->class || ids->vendor || ids->device) {
            if (sdio_match_one(func, ids))
                return ids;
            ids++;
        }
    }

    return NULL;
}

static int sdio_bus_match(struct device *dev, struct device_driver *drv)
{
    struct sdio_func *func = dev_to_sdio_func(dev);
    struct sdio_driver *sdrv = to_sdio_driver(drv);

    if (sdio_match_device(func, sdrv))
        return 1;

    return 0;
}

static int
sdio_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
{
    struct sdio_func *func = dev_to_sdio_func(dev);

    if (add_uevent_var(env,
            "SDIO_CLASS=%02X", func->class))
        return -ENOMEM;

    if (add_uevent_var(env, 
            "SDIO_ID=%04X:%04X", func->vendor, func->device))
        return -ENOMEM;

    if (add_uevent_var(env,
            "MODALIAS=sdio:c%02Xv%04Xd%04X",
            func->class, func->vendor, func->device))
        return -ENOMEM;

    return 0;
}

static int sdio_bus_probe(struct device *dev)
{
    struct sdio_driver *drv = to_sdio_driver(dev->driver);
    struct sdio_func *func = dev_to_sdio_func(dev);
    const struct sdio_device_id *id;
    int ret;

    id = sdio_match_device(func, drv);
    if (!id)
        return -ENODEV;

    /* Unbound SDIO functions are always suspended.
     * During probe, the function is set active and the usage count
     * is incremented.  If the driver supports runtime PM,
     * it should call pm_runtime_put_noidle() in its probe routine and
     * pm_runtime_get_noresume() in its remove routine.
     */
    if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD) {
        ret = pm_runtime_get_sync(dev);
        if (ret < 0)
            goto out;
    }

    /* Set the default block size so the driver is sure it's something
     * sensible. */
    sdio_claim_host(func);
    ret = sdio_set_block_size(func, 0);
    sdio_release_host(func);
    if (ret)
        goto disable_runtimepm;

    ret = drv->probe(func, id);
    if (ret)
        goto disable_runtimepm;

    return 0;

disable_runtimepm:
    if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
        pm_runtime_put_noidle(dev);
out:
    return ret;
}

static int sdio_bus_remove(struct device *dev)
{
    struct sdio_driver *drv = to_sdio_driver(dev->driver);
    struct sdio_func *func = dev_to_sdio_func(dev);
    int ret = 0;

    /* Make sure card is powered before invoking ->remove() */
    if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
        pm_runtime_get_sync(dev);

    drv->remove(func);

    if (func->irq_handler) {
        pr_warning("WARNING: driver %s did not remove "
            "its interrupt handler!\n", drv->name);
        sdio_claim_host(func);
        sdio_release_irq(func);
        sdio_release_host(func);
    }

    /* First, undo the increment made directly above */
    if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
        pm_runtime_put_noidle(dev);

    /* Then undo the runtime PM settings in sdio_bus_probe() */
    if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
        pm_runtime_put_sync(dev);

    return ret;
}

#ifdef CONFIG_PM
static const struct dev_pm_ops sdio_bus_pm_ops = {
    SET_RUNTIME_PM_OPS(
        pm_generic_runtime_suspend,
        pm_generic_runtime_resume,
        pm_generic_runtime_idle
    )
};

#define SDIO_PM_OPS_PTR (&sdio_bus_pm_ops)

#else /* !CONFIG_PM */

#define SDIO_PM_OPS_PTR NULL

#endif /* !CONFIG_PM */

static struct bus_type sdio_bus_type = {
    .name       = "sdio",
    .dev_attrs  = sdio_dev_attrs,
    .match      = sdio_bus_match,
    .uevent     = sdio_bus_uevent,
    .probe      = sdio_bus_probe,
    .remove     = sdio_bus_remove,
    .pm     = SDIO_PM_OPS_PTR,
};

int sdio_register_bus(void)
{
    return bus_register(&sdio_bus_type);
}

void sdio_unregister_bus(void)
{
    bus_unregister(&sdio_bus_type);
}

int sdio_register_driver(struct sdio_driver *drv)
{
    drv->drv.name = drv->name;
    drv->drv.bus = &sdio_bus_type;
    return driver_register(&drv->drv);
}
EXPORT_SYMBOL_GPL(sdio_register_driver);

void sdio_unregister_driver(struct sdio_driver *drv)
{
    drv->drv.bus = &sdio_bus_type;
    driver_unregister(&drv->drv);
}
EXPORT_SYMBOL_GPL(sdio_unregister_driver);

static void sdio_release_func(struct device *dev)
{
    struct sdio_func *func = dev_to_sdio_func(dev);

    sdio_free_func_cis(func);

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

    kfree(func);
}

/*
 * Allocate and initialise a new SDIO function structure.
 */
struct sdio_func *sdio_alloc_func(struct mmc_card *card)
{
    struct sdio_func *func;

    func = kzalloc(sizeof(struct sdio_func), GFP_KERNEL);
    if (!func)
        return ERR_PTR(-ENOMEM);

    func->card = card;

    device_initialize(&func->dev);

    func->dev.parent = &card->dev;
    func->dev.bus = &sdio_bus_type;
    func->dev.release = sdio_release_func;

    return func;
}

/*
 * Register a new SDIO function with the driver model.
 */
int sdio_add_func(struct sdio_func *func)
{
    int ret;

    dev_set_name(&func->dev, "%s:%d", mmc_card_id(func->card), func->num);

    ret = device_add(&func->dev);
    if (ret == 0)
        sdio_func_set_present(func);

    return ret;
}

/*
 * Unregister a SDIO function with the driver model, and
 * (eventually) free it.
 * This function can be called through error paths where sdio_add_func() was
 * never executed (because a failure occurred at an earlier point).
 */
void sdio_remove_func(struct sdio_func *func)
{
    if (!sdio_func_present(func))
        return;

    device_del(&func->dev);
    put_device(&func->dev);
}