platform.c

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/*
 * platform.c - platform 'pseudo' bus for legacy devices
 *
 * Copyright (c) 2002-3 Patrick Mochel
 * Copyright (c) 2002-3 Open Source Development Labs
 *
 * This file is released under the GPLv2
 *
 * Please see Documentation/driver-model/platform.txt for more
 * information.
 */

#include <linux/string.h>
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/dma-mapping.h>
#include <linux/bootmem.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/idr.h>

#include "base.h"
#include "power/power.h"

/* For automatically allocated device IDs */
static DEFINE_IDA(platform_devid_ida);

#define to_platform_driver(drv) (container_of((drv), struct platform_driver, \
                 driver))

struct device platform_bus = {
    .init_name  = "platform",
};
EXPORT_SYMBOL_GPL(platform_bus);

void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
{
}

struct resource *platform_get_resource(struct platform_device *dev,
                       unsigned int type, unsigned int num)
{
    int i;

    for (i = 0; i < dev->num_resources; i++) {
        struct resource *r = &dev->resource[i];

        if (type == resource_type(r) && num-- == 0)
            return r;
    }
    return NULL;
}
EXPORT_SYMBOL_GPL(platform_get_resource);

int platform_get_irq(struct platform_device *dev, unsigned int num)
{
#ifdef CONFIG_SPARC
    /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
    if (!dev || num >= dev->archdata.num_irqs)
        return -ENXIO;
    return dev->archdata.irqs[num];
#else
    struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);

    return r ? r->start : -ENXIO;
#endif
}
EXPORT_SYMBOL_GPL(platform_get_irq);

struct resource *platform_get_resource_byname(struct platform_device *dev,
                          unsigned int type,
                          const char *name)
{
    int i;

    for (i = 0; i < dev->num_resources; i++) {
        struct resource *r = &dev->resource[i];

        if (unlikely(!r->name))
            continue;

        if (type == resource_type(r) && !strcmp(r->name, name))
            return r;
    }
    return NULL;
}
EXPORT_SYMBOL_GPL(platform_get_resource_byname);

int platform_get_irq_byname(struct platform_device *dev, const char *name)
{
    struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
                              name);

    return r ? r->start : -ENXIO;
}
EXPORT_SYMBOL_GPL(platform_get_irq_byname);

int platform_add_devices(struct platform_device **devs, int num)
{
    int i, ret = 0;

    for (i = 0; i < num; i++) {
        ret = platform_device_register(devs[i]);
        if (ret) {
            while (--i >= 0)
                platform_device_unregister(devs[i]);
            break;
        }
    }

    return ret;
}
EXPORT_SYMBOL_GPL(platform_add_devices);

struct platform_object {
    struct platform_device pdev;
    char name[1];
};

void platform_device_put(struct platform_device *pdev)
{
    if (pdev)
        put_device(&pdev->dev);
}
EXPORT_SYMBOL_GPL(platform_device_put);

static void platform_device_release(struct device *dev)
{
    struct platform_object *pa = container_of(dev, struct platform_object,
                          pdev.dev);

    of_device_node_put(&pa->pdev.dev);
    kfree(pa->pdev.dev.platform_data);
    kfree(pa->pdev.mfd_cell);
    kfree(pa->pdev.resource);
    kfree(pa);
}

struct platform_device *platform_device_alloc(const char *name, int id)
{
    struct platform_object *pa;

    pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
    if (pa) {
        strcpy(pa->name, name);
        pa->pdev.name = pa->name;
        pa->pdev.id = id;
        device_initialize(&pa->pdev.dev);
        pa->pdev.dev.release = platform_device_release;
        arch_setup_pdev_archdata(&pa->pdev);
    }

    return pa ? &pa->pdev : NULL;
}
EXPORT_SYMBOL_GPL(platform_device_alloc);

int platform_device_add_resources(struct platform_device *pdev,
                  const struct resource *res, unsigned int num)
{
    struct resource *r = NULL;

    if (res) {
        r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
        if (!r)
            return -ENOMEM;
    }

    kfree(pdev->resource);
    pdev->resource = r;
    pdev->num_resources = num;
    return 0;
}
EXPORT_SYMBOL_GPL(platform_device_add_resources);

int platform_device_add_data(struct platform_device *pdev, const void *data,
                 size_t size)
{
    void *d = NULL;

    if (data) {
        d = kmemdup(data, size, GFP_KERNEL);
        if (!d)
            return -ENOMEM;
    }

    kfree(pdev->dev.platform_data);
    pdev->dev.platform_data = d;
    return 0;
}
EXPORT_SYMBOL_GPL(platform_device_add_data);

int platform_device_add(struct platform_device *pdev)
{
    int i, ret;

    if (!pdev)
        return -EINVAL;

    if (!pdev->dev.parent)
        pdev->dev.parent = &platform_bus;

    pdev->dev.bus = &platform_bus_type;

    switch (pdev->id) {
    default:
        dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
        break;
    case PLATFORM_DEVID_NONE:
        dev_set_name(&pdev->dev, "%s", pdev->name);
        break;
    case PLATFORM_DEVID_AUTO:
        /*
         * Automatically allocated device ID. We mark it as such so
         * that we remember it must be freed, and we append a suffix
         * to avoid namespace collision with explicit IDs.
         */
        ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
        if (ret < 0)
            goto err_out;
        pdev->id = ret;
        pdev->id_auto = true;
        dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
        break;
    }

    for (i = 0; i < pdev->num_resources; i++) {
        struct resource *p, *r = &pdev->resource[i];

        if (r->name == NULL)
            r->name = dev_name(&pdev->dev);

        p = r->parent;
        if (!p) {
            if (resource_type(r) == IORESOURCE_MEM)
                p = &iomem_resource;
            else if (resource_type(r) == IORESOURCE_IO)
                p = &ioport_resource;
        }

        if (p && insert_resource(p, r)) {
            printk(KERN_ERR
                   "%s: failed to claim resource %d\n",
                   dev_name(&pdev->dev), i);
            ret = -EBUSY;
            goto failed;
        }
    }

    pr_debug("Registering platform device '%s'. Parent at %s\n",
         dev_name(&pdev->dev), dev_name(pdev->dev.parent));

    ret = device_add(&pdev->dev);
    if (ret == 0)
        return ret;

 failed:
    if (pdev->id_auto) {
        ida_simple_remove(&platform_devid_ida, pdev->id);
        pdev->id = PLATFORM_DEVID_AUTO;
    }

    while (--i >= 0) {
        struct resource *r = &pdev->resource[i];
        unsigned long type = resource_type(r);

        if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
            release_resource(r);
    }

 err_out:
    return ret;
}
EXPORT_SYMBOL_GPL(platform_device_add);

void platform_device_del(struct platform_device *pdev)
{
    int i;

    if (pdev) {
        device_del(&pdev->dev);

        if (pdev->id_auto) {
            ida_simple_remove(&platform_devid_ida, pdev->id);
            pdev->id = PLATFORM_DEVID_AUTO;
        }

        for (i = 0; i < pdev->num_resources; i++) {
            struct resource *r = &pdev->resource[i];
            unsigned long type = resource_type(r);

            if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
                release_resource(r);
        }
    }
}
EXPORT_SYMBOL_GPL(platform_device_del);

int platform_device_register(struct platform_device *pdev)
{
    device_initialize(&pdev->dev);
    arch_setup_pdev_archdata(pdev);
    return platform_device_add(pdev);
}
EXPORT_SYMBOL_GPL(platform_device_register);

void platform_device_unregister(struct platform_device *pdev)
{
    platform_device_del(pdev);
    platform_device_put(pdev);
}
EXPORT_SYMBOL_GPL(platform_device_unregister);

struct platform_device *platform_device_register_full(
        const struct platform_device_info *pdevinfo)
{
    int ret = -ENOMEM;
    struct platform_device *pdev;

    pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
    if (!pdev)
        goto err_alloc;

    pdev->dev.parent = pdevinfo->parent;

    if (pdevinfo->dma_mask) {
        /*
         * This memory isn't freed when the device is put,
         * I don't have a nice idea for that though.  Conceptually
         * dma_mask in struct device should not be a pointer.
         * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
         */
        pdev->dev.dma_mask =
            kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
        if (!pdev->dev.dma_mask)
            goto err;

        *pdev->dev.dma_mask = pdevinfo->dma_mask;
        pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
    }

    ret = platform_device_add_resources(pdev,
            pdevinfo->res, pdevinfo->num_res);
    if (ret)
        goto err;

    ret = platform_device_add_data(pdev,
            pdevinfo->data, pdevinfo->size_data);
    if (ret)
        goto err;

    ret = platform_device_add(pdev);
    if (ret) {
err:
        kfree(pdev->dev.dma_mask);

err_alloc:
        platform_device_put(pdev);
        return ERR_PTR(ret);
    }

    return pdev;
}
EXPORT_SYMBOL_GPL(platform_device_register_full);

static int platform_drv_probe(struct device *_dev)
{
    struct platform_driver *drv = to_platform_driver(_dev->driver);
    struct platform_device *dev = to_platform_device(_dev);

    return drv->probe(dev);
}

static int platform_drv_probe_fail(struct device *_dev)
{
    return -ENXIO;
}

static int platform_drv_remove(struct device *_dev)
{
    struct platform_driver *drv = to_platform_driver(_dev->driver);
    struct platform_device *dev = to_platform_device(_dev);

    return drv->remove(dev);
}

static void platform_drv_shutdown(struct device *_dev)
{
    struct platform_driver *drv = to_platform_driver(_dev->driver);
    struct platform_device *dev = to_platform_device(_dev);

    drv->shutdown(dev);
}

int platform_driver_register(struct platform_driver *drv)
{
    drv->driver.bus = &platform_bus_type;
    if (drv->probe)
        drv->driver.probe = platform_drv_probe;
    if (drv->remove)
        drv->driver.remove = platform_drv_remove;
    if (drv->shutdown)
        drv->driver.shutdown = platform_drv_shutdown;

    return driver_register(&drv->driver);
}
EXPORT_SYMBOL_GPL(platform_driver_register);

void platform_driver_unregister(struct platform_driver *drv)
{
    driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(platform_driver_unregister);

int __init_or_module platform_driver_probe(struct platform_driver *drv,
        int (*probe)(struct platform_device *))
{
    int retval, code;

    /* make sure driver won't have bind/unbind attributes */
    drv->driver.suppress_bind_attrs = true;

    /* temporary section violation during probe() */
    drv->probe = probe;
    retval = code = platform_driver_register(drv);

    /*
     * Fixup that section violation, being paranoid about code scanning
     * the list of drivers in order to probe new devices.  Check to see
     * if the probe was successful, and make sure any forced probes of
     * new devices fail.
     */
    spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
    drv->probe = NULL;
    if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
        retval = -ENODEV;
    drv->driver.probe = platform_drv_probe_fail;
    spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);

    if (code != retval)
        platform_driver_unregister(drv);
    return retval;
}
EXPORT_SYMBOL_GPL(platform_driver_probe);

struct platform_device * __init_or_module platform_create_bundle(
            struct platform_driver *driver,
            int (*probe)(struct platform_device *),
            struct resource *res, unsigned int n_res,
            const void *data, size_t size)
{
    struct platform_device *pdev;
    int error;

    pdev = platform_device_alloc(driver->driver.name, -1);
    if (!pdev) {
        error = -ENOMEM;
        goto err_out;
    }

    error = platform_device_add_resources(pdev, res, n_res);
    if (error)
        goto err_pdev_put;

    error = platform_device_add_data(pdev, data, size);
    if (error)
        goto err_pdev_put;

    error = platform_device_add(pdev);
    if (error)
        goto err_pdev_put;

    error = platform_driver_probe(driver, probe);
    if (error)
        goto err_pdev_del;

    return pdev;

err_pdev_del:
    platform_device_del(pdev);
err_pdev_put:
    platform_device_put(pdev);
err_out:
    return ERR_PTR(error);
}
EXPORT_SYMBOL_GPL(platform_create_bundle);

/* modalias support enables more hands-off userspace setup:
 * (a) environment variable lets new-style hotplug events work once system is
 *     fully running:  "modprobe $MODALIAS"
 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
 */
static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
                 char *buf)
{
    struct platform_device  *pdev = to_platform_device(dev);
    int len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);

    return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
}

static struct device_attribute platform_dev_attrs[] = {
    __ATTR_RO(modalias),
    __ATTR_NULL,
};

static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
{
    struct platform_device  *pdev = to_platform_device(dev);
    int rc;

    /* Some devices have extra OF data and an OF-style MODALIAS */
    rc = of_device_uevent_modalias(dev,env);
    if (rc != -ENODEV)
        return rc;

    add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
            pdev->name);
    return 0;
}

static const struct platform_device_id *platform_match_id(
            const struct platform_device_id *id,
            struct platform_device *pdev)
{
    while (id->name[0]) {
        if (strcmp(pdev->name, id->name) == 0) {
            pdev->id_entry = id;
            return id;
        }
        id++;
    }
    return NULL;
}

static int platform_match(struct device *dev, struct device_driver *drv)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct platform_driver *pdrv = to_platform_driver(drv);

    /* Attempt an OF style match first */
    if (of_driver_match_device(dev, drv))
        return 1;

    /* Then try to match against the id table */
    if (pdrv->id_table)
        return platform_match_id(pdrv->id_table, pdev) != NULL;

    /* fall-back to driver name match */
    return (strcmp(pdev->name, drv->name) == 0);
}

#ifdef CONFIG_PM_SLEEP

static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
{
    struct platform_driver *pdrv = to_platform_driver(dev->driver);
    struct platform_device *pdev = to_platform_device(dev);
    int ret = 0;

    if (dev->driver && pdrv->suspend)
        ret = pdrv->suspend(pdev, mesg);

    return ret;
}

static int platform_legacy_resume(struct device *dev)
{
    struct platform_driver *pdrv = to_platform_driver(dev->driver);
    struct platform_device *pdev = to_platform_device(dev);
    int ret = 0;

    if (dev->driver && pdrv->resume)
        ret = pdrv->resume(pdev);

    return ret;
}

#endif /* CONFIG_PM_SLEEP */

#ifdef CONFIG_SUSPEND

int platform_pm_suspend(struct device *dev)
{
    struct device_driver *drv = dev->driver;
    int ret = 0;

    if (!drv)
        return 0;

    if (drv->pm) {
        if (drv->pm->suspend)
            ret = drv->pm->suspend(dev);
    } else {
        ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
    }

    return ret;
}

int platform_pm_resume(struct device *dev)
{
    struct device_driver *drv = dev->driver;
    int ret = 0;

    if (!drv)
        return 0;

    if (drv->pm) {
        if (drv->pm->resume)
            ret = drv->pm->resume(dev);
    } else {
        ret = platform_legacy_resume(dev);
    }

    return ret;
}

#endif /* CONFIG_SUSPEND */

#ifdef CONFIG_HIBERNATE_CALLBACKS

int platform_pm_freeze(struct device *dev)
{
    struct device_driver *drv = dev->driver;
    int ret = 0;

    if (!drv)
        return 0;

    if (drv->pm) {
        if (drv->pm->freeze)
            ret = drv->pm->freeze(dev);
    } else {
        ret = platform_legacy_suspend(dev, PMSG_FREEZE);
    }

    return ret;
}

int platform_pm_thaw(struct device *dev)
{
    struct device_driver *drv = dev->driver;
    int ret = 0;

    if (!drv)
        return 0;

    if (drv->pm) {
        if (drv->pm->thaw)
            ret = drv->pm->thaw(dev);
    } else {
        ret = platform_legacy_resume(dev);
    }

    return ret;
}

int platform_pm_poweroff(struct device *dev)
{
    struct device_driver *drv = dev->driver;
    int ret = 0;

    if (!drv)
        return 0;

    if (drv->pm) {
        if (drv->pm->poweroff)
            ret = drv->pm->poweroff(dev);
    } else {
        ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
    }

    return ret;
}

int platform_pm_restore(struct device *dev)
{
    struct device_driver *drv = dev->driver;
    int ret = 0;

    if (!drv)
        return 0;

    if (drv->pm) {
        if (drv->pm->restore)
            ret = drv->pm->restore(dev);
    } else {
        ret = platform_legacy_resume(dev);
    }

    return ret;
}

#endif /* CONFIG_HIBERNATE_CALLBACKS */

static const struct dev_pm_ops platform_dev_pm_ops = {
    .runtime_suspend = pm_generic_runtime_suspend,
    .runtime_resume = pm_generic_runtime_resume,
    .runtime_idle = pm_generic_runtime_idle,
    USE_PLATFORM_PM_SLEEP_OPS
};

struct bus_type platform_bus_type = {
    .name       = "platform",
    .dev_attrs  = platform_dev_attrs,
    .match      = platform_match,
    .uevent     = platform_uevent,
    .pm     = &platform_dev_pm_ops,
};
EXPORT_SYMBOL_GPL(platform_bus_type);

int __init platform_bus_init(void)
{
    int error;

    early_platform_cleanup();

    error = device_register(&platform_bus);
    if (error)
        return error;
    error =  bus_register(&platform_bus_type);
    if (error)
        device_unregister(&platform_bus);
    return error;
}

#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
u64 dma_get_required_mask(struct device *dev)
{
    u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
    u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
    u64 mask;

    if (!high_totalram) {
        /* convert to mask just covering totalram */
        low_totalram = (1 << (fls(low_totalram) - 1));
        low_totalram += low_totalram - 1;
        mask = low_totalram;
    } else {
        high_totalram = (1 << (fls(high_totalram) - 1));
        high_totalram += high_totalram - 1;
        mask = (((u64)high_totalram) << 32) + 0xffffffff;
    }
    return mask;
}
EXPORT_SYMBOL_GPL(dma_get_required_mask);
#endif

static __initdata LIST_HEAD(early_platform_driver_list);
static __initdata LIST_HEAD(early_platform_device_list);

int __init early_platform_driver_register(struct early_platform_driver *epdrv,
                      char *buf)
{
    char *tmp;
    int n;

    /* Simply add the driver to the end of the global list.
     * Drivers will by default be put on the list in compiled-in order.
     */
    if (!epdrv->list.next) {
        INIT_LIST_HEAD(&epdrv->list);
        list_add_tail(&epdrv->list, &early_platform_driver_list);
    }

    /* If the user has specified device then make sure the driver
     * gets prioritized. The driver of the last device specified on
     * command line will be put first on the list.
     */
    n = strlen(epdrv->pdrv->driver.name);
    if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
        list_move(&epdrv->list, &early_platform_driver_list);

        /* Allow passing parameters after device name */
        if (buf[n] == '\0' || buf[n] == ',')
            epdrv->requested_id = -1;
        else {
            epdrv->requested_id = simple_strtoul(&buf[n + 1],
                                 &tmp, 10);

            if (buf[n] != '.' || (tmp == &buf[n + 1])) {
                epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
                n = 0;
            } else
                n += strcspn(&buf[n + 1], ",") + 1;
        }

        if (buf[n] == ',')
            n++;

        if (epdrv->bufsize) {
            memcpy(epdrv->buffer, &buf[n],
                   min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
            epdrv->buffer[epdrv->bufsize - 1] = '\0';
        }
    }

    return 0;
}

void __init early_platform_add_devices(struct platform_device **devs, int num)
{
    struct device *dev;
    int i;

    /* simply add the devices to list */
    for (i = 0; i < num; i++) {
        dev = &devs[i]->dev;

        if (!dev->devres_head.next) {
            pm_runtime_early_init(dev);
            INIT_LIST_HEAD(&dev->devres_head);
            list_add_tail(&dev->devres_head,
                      &early_platform_device_list);
        }
    }
}

void __init early_platform_driver_register_all(char *class_str)
{
    /* The "class_str" parameter may or may not be present on the kernel
     * command line. If it is present then there may be more than one
     * matching parameter.
     *
     * Since we register our early platform drivers using early_param()
     * we need to make sure that they also get registered in the case
     * when the parameter is missing from the kernel command line.
     *
     * We use parse_early_options() to make sure the early_param() gets
     * called at least once. The early_param() may be called more than
     * once since the name of the preferred device may be specified on
     * the kernel command line. early_platform_driver_register() handles
     * this case for us.
     */
    parse_early_options(class_str);
}

static  __init struct platform_device *
early_platform_match(struct early_platform_driver *epdrv, int id)
{
    struct platform_device *pd;

    list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
        if (platform_match(&pd->dev, &epdrv->pdrv->driver))
            if (pd->id == id)
                return pd;

    return NULL;
}

static  __init int early_platform_left(struct early_platform_driver *epdrv,
                       int id)
{
    struct platform_device *pd;

    list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
        if (platform_match(&pd->dev, &epdrv->pdrv->driver))
            if (pd->id >= id)
                return 1;

    return 0;
}

static int __init early_platform_driver_probe_id(char *class_str,
                         int id,
                         int nr_probe)
{
    struct early_platform_driver *epdrv;
    struct platform_device *match;
    int match_id;
    int n = 0;
    int left = 0;

    list_for_each_entry(epdrv, &early_platform_driver_list, list) {
        /* only use drivers matching our class_str */
        if (strcmp(class_str, epdrv->class_str))
            continue;

        if (id == -2) {
            match_id = epdrv->requested_id;
            left = 1;

        } else {
            match_id = id;
            left += early_platform_left(epdrv, id);

            /* skip requested id */
            switch (epdrv->requested_id) {
            case EARLY_PLATFORM_ID_ERROR:
            case EARLY_PLATFORM_ID_UNSET:
                break;
            default:
                if (epdrv->requested_id == id)
                    match_id = EARLY_PLATFORM_ID_UNSET;
            }
        }

        switch (match_id) {
        case EARLY_PLATFORM_ID_ERROR:
            pr_warning("%s: unable to parse %s parameter\n",
                   class_str, epdrv->pdrv->driver.name);
            /* fall-through */
        case EARLY_PLATFORM_ID_UNSET:
            match = NULL;
            break;
        default:
            match = early_platform_match(epdrv, match_id);
        }

        if (match) {
            /*
             * Set up a sensible init_name to enable
             * dev_name() and others to be used before the
             * rest of the driver core is initialized.
             */
            if (!match->dev.init_name && slab_is_available()) {
                if (match->id != -1)
                    match->dev.init_name =
                        kasprintf(GFP_KERNEL, "%s.%d",
                              match->name,
                              match->id);
                else
                    match->dev.init_name =
                        kasprintf(GFP_KERNEL, "%s",
                              match->name);

                if (!match->dev.init_name)
                    return -ENOMEM;
            }

            if (epdrv->pdrv->probe(match))
                pr_warning("%s: unable to probe %s early.\n",
                       class_str, match->name);
            else
                n++;
        }

        if (n >= nr_probe)
            break;
    }

    if (left)
        return n;
    else
        return -ENODEV;
}

int __init early_platform_driver_probe(char *class_str,
                       int nr_probe,
                       int user_only)
{
    int k, n, i;

    n = 0;
    for (i = -2; n < nr_probe; i++) {
        k = early_platform_driver_probe_id(class_str, i, nr_probe - n);

        if (k < 0)
            break;

        n += k;

        if (user_only)
            break;
    }

    return n;
}

void __init early_platform_cleanup(void)
{
    struct platform_device *pd, *pd2;

    /* clean up the devres list used to chain devices */
    list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
                 dev.devres_head) {
        list_del(&pd->dev.devres_head);
        memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
    }
}