linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * bus.c - bus driver management

 *

 * Copyright (c) 2002-3 Patrick Mochel

 * Copyright (c) 2002-3 Open Source Development Labs

 * Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de>

 * Copyright (c) 2007 Novell Inc.

 */

​

#include <linux/async.h>

#include <linux/device.h>

#include <linux/module.h>

#include <linux/errno.h>

#include <linux/slab.h>

#include <linux/init.h>

#include <linux/string.h>

#include <linux/mutex.h>

#include <linux/sysfs.h>

#include "base.h"

#include "power/power.h"

​

/* /sys/devices/system */

static struct kset *system_kset;

​

#define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr)

​

/*

 * sysfs bindings for drivers

 */

​

#define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr)

​

#define DRIVER_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \

    struct driver_attribute driver_attr_##_name =       \

        __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)

​

static int __must_check bus_rescan_devices_helper(struct device *dev,

                        void *data);

​

static struct bus_type *bus_get(struct bus_type *bus)

{

    if (bus) {

        kset_get(&bus->p->subsys);

        return bus;

    }

    return NULL;

}

​

static void bus_put(struct bus_type *bus)

{

    if (bus)

        kset_put(&bus->p->subsys);

}

​

static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr,

                 char *buf)

{

    struct driver_attribute *drv_attr = to_drv_attr(attr);

    struct driver_private *drv_priv = to_driver(kobj);

    ssize_t ret = -EIO;

​

    if (drv_attr->show)

        ret = drv_attr->show(drv_priv->driver, buf);

    return ret;

}

​

static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr,

                  const char *buf, size_t count)

{

    struct driver_attribute *drv_attr = to_drv_attr(attr);

    struct driver_private *drv_priv = to_driver(kobj);

    ssize_t ret = -EIO;

​

    if (drv_attr->store)

        ret = drv_attr->store(drv_priv->driver, buf, count);

    return ret;

}

​

static const struct sysfs_ops driver_sysfs_ops = {

    .show   = drv_attr_show,

    .store  = drv_attr_store,

};

​

static void driver_release(struct kobject *kobj)

{

    struct driver_private *drv_priv = to_driver(kobj);

​

    pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__);

    kfree(drv_priv);

}

​