wpan-class.c

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/*
 * Copyright (C) 2007, 2008, 2009 Siemens AG
 *
 * 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.
 *
 * 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */

#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>

#include <net/wpan-phy.h>

#include "ieee802154.h"

#define MASTER_SHOW_COMPLEX(name, format_string, args...)       \
static ssize_t name ## _show(struct device *dev,            \
                struct device_attribute *attr, char *buf)   \
{                                   \
    struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev); \
    int ret;                            \
                                    \
    mutex_lock(&phy->pib_lock);                 \
    ret = snprintf(buf, PAGE_SIZE, format_string "\n", args);   \
    mutex_unlock(&phy->pib_lock);                   \
    return ret;                         \
}

#define MASTER_SHOW(field, format_string)               \
    MASTER_SHOW_COMPLEX(field, format_string, phy->field)

MASTER_SHOW(current_channel, "%d");
MASTER_SHOW(current_page, "%d");
MASTER_SHOW_COMPLEX(transmit_power, "%d +- %d dB",
    ((signed char) (phy->transmit_power << 2)) >> 2,
    (phy->transmit_power >> 6) ? (phy->transmit_power >> 6) * 3 : 1 );
MASTER_SHOW(cca_mode, "%d");

static ssize_t channels_supported_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev);
    int ret;
    int i, len = 0;

    mutex_lock(&phy->pib_lock);
    for (i = 0; i < 32; i++) {
        ret = snprintf(buf + len, PAGE_SIZE - len,
                "%#09x\n", phy->channels_supported[i]);
        if (ret < 0)
            break;
        len += ret;
    }
    mutex_unlock(&phy->pib_lock);
    return len;
}

static struct device_attribute pmib_attrs[] = {
    __ATTR_RO(current_channel),
    __ATTR_RO(current_page),
    __ATTR_RO(channels_supported),
    __ATTR_RO(transmit_power),
    __ATTR_RO(cca_mode),
    {},
};

static void wpan_phy_release(struct device *d)
{
    struct wpan_phy *phy = container_of(d, struct wpan_phy, dev);
    kfree(phy);
}

static struct class wpan_phy_class = {
    .name = "ieee802154",
    .dev_release = wpan_phy_release,
    .dev_attrs = pmib_attrs,
};

static DEFINE_MUTEX(wpan_phy_mutex);
static int wpan_phy_idx;

static int wpan_phy_match(struct device *dev, void *data)
{
    return !strcmp(dev_name(dev), (const char *)data);
}

struct wpan_phy *wpan_phy_find(const char *str)
{
    struct device *dev;

    if (WARN_ON(!str))
        return NULL;

    dev = class_find_device(&wpan_phy_class, NULL,
            (void *)str, wpan_phy_match);
    if (!dev)
        return NULL;

    return container_of(dev, struct wpan_phy, dev);
}
EXPORT_SYMBOL(wpan_phy_find);

struct wpan_phy_iter_data {
    int (*fn)(struct wpan_phy *phy, void *data);
    void *data;
};

static int wpan_phy_iter(struct device *dev, void *_data)
{
    struct wpan_phy_iter_data *wpid = _data;
    struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev);
    return wpid->fn(phy, wpid->data);
}

int wpan_phy_for_each(int (*fn)(struct wpan_phy *phy, void *data),
        void *data)
{
    struct wpan_phy_iter_data wpid = {
        .fn = fn,
        .data = data,
    };

    return class_for_each_device(&wpan_phy_class, NULL,
            &wpid, wpan_phy_iter);
}
EXPORT_SYMBOL(wpan_phy_for_each);

static int wpan_phy_idx_valid(int idx)
{
    return idx >= 0;
}

struct wpan_phy *wpan_phy_alloc(size_t priv_size)
{
    struct wpan_phy *phy = kzalloc(sizeof(*phy) + priv_size,
            GFP_KERNEL);

    if (!phy)
        goto out;
    mutex_lock(&wpan_phy_mutex);
    phy->idx = wpan_phy_idx++;
    if (unlikely(!wpan_phy_idx_valid(phy->idx))) {
        wpan_phy_idx--;
        mutex_unlock(&wpan_phy_mutex);
        kfree(phy);
        goto out;
    }
    mutex_unlock(&wpan_phy_mutex);

    mutex_init(&phy->pib_lock);

    device_initialize(&phy->dev);
    dev_set_name(&phy->dev, "wpan-phy%d", phy->idx);

    phy->dev.class = &wpan_phy_class;

    phy->current_channel = -1; /* not initialised */
    phy->current_page = 0; /* for compatibility */

    return phy;

out:
    return NULL;
}
EXPORT_SYMBOL(wpan_phy_alloc);

int wpan_phy_register(struct wpan_phy *phy)
{
    return device_add(&phy->dev);
}
EXPORT_SYMBOL(wpan_phy_register);

void wpan_phy_unregister(struct wpan_phy *phy)
{
    device_del(&phy->dev);
}
EXPORT_SYMBOL(wpan_phy_unregister);

void wpan_phy_free(struct wpan_phy *phy)
{
    put_device(&phy->dev);
}
EXPORT_SYMBOL(wpan_phy_free);

static int __init wpan_phy_class_init(void)
{
    int rc;
    rc = class_register(&wpan_phy_class);
    if (rc)
        goto err;

    rc = ieee802154_nl_init();
    if (rc)
        goto err_nl;

    return 0;
err_nl:
    class_unregister(&wpan_phy_class);
err:
    return rc;
}
subsys_initcall(wpan_phy_class_init);

static void __exit wpan_phy_class_exit(void)
{
    ieee802154_nl_exit();
    class_unregister(&wpan_phy_class);
}
module_exit(wpan_phy_class_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("IEEE 802.15.4 configuration interface");
MODULE_AUTHOR("Dmitry Eremin-Solenikov");