/*
* Copyright (C) 2006 Ivo van Doorn
* Copyright (C) 2007 Dmitry Torokhov
*
* 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.
*
* 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.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/workqueue.h>
#include <linux/capability.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/rfkill.h>
MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
MODULE_VERSION("1.0");
MODULE_DESCRIPTION("RF switch support");
MODULE_LICENSE("GPL");
static LIST_HEAD(rfkill_list); /* list of registered rf switches */
static DEFINE_MUTEX(rfkill_mutex);
static enum rfkill_state rfkill_states[RFKILL_TYPE_MAX];
static int rfkill_toggle_radio(struct rfkill *rfkill,
enum rfkill_state state)
{
int retval;
retval = mutex_lock_interruptible(&rfkill->mutex);
if (retval)
return retval;
if (state != rfkill->state) {
retval = rfkill->toggle_radio(rfkill->data, state);
if (!retval)
rfkill->state = state;
}
mutex_unlock(&rfkill->mutex);
return retval;
}
/**
* rfkill_switch_all - Toggle state of all switches of given type
* @type: type of interfaces to be affeceted
* @state: the new state
*
* This function toggles state of all switches of given type unless
* a specific switch is claimed by userspace in which case it is
* left alone.
*/
void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state)
{
struct rfkill *rfkill;
mutex_lock(&rfkill_mutex);
rfkill_states[type] = state;
list_for_each_entry(rfkill, &rfkill_list, node) {
if (!rfkill->user_claim)
rfkill_toggle_radio(rfkill, state);
}
mutex_unlock(&rfkill_mutex);
}
EXPORT_SYMBOL(rfkill_switch_all);
static ssize_t rfkill_name_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%s\n", rfkill->name);
}
static ssize_t rfkill_type_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
const char *type;
switch (rfkill->type) {
case RFKILL_TYPE_WLAN:
type = "wlan";
break;
case RFKILL_TYPE_BLUETOOTH:
type = "bluetooth";
break;
case RFKILL_TYPE_IRDA:
type = "irda";
break;
default:
BUG();
}
return sprintf(buf, "%s\n", type);
}
static ssize_t rfkill_state_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%d\n", rfkill->state);
}
static ssize_t rfkill_state_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct rfkill *rfkill = to_rfkill(dev);
unsigned int state = simple_strtoul(buf, NULL, 0);
int error;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
error = rfkill_toggle_radio(rfkill,
state ? RFKILL_STATE_ON : RFKILL_STATE_OFF);
if (error)
return error;
return count;
}
static ssize_t rfkill_claim_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%d", rfkill->user_claim);
}
static ssize_t rfkill_claim_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct rfkill *rfkill = to_rfkill(dev);
bool claim = !!simple_strtoul(buf, NULL, 0);
int error;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
/*
* Take the global lock to make sure the kernel is not in
* the middle of rfkill_switch_all
*/
error = mutex_lock_interruptible(&rfkill_mutex);
if (error)
return error;
if (rfkill->user_claim != claim) {
if (!claim)
rfkill_toggle_radio(rfkill,
rfkill_states[rfkill->type]);
rfkill->user_claim = claim;
}
mutex_unlock(&rfkill_mutex);
return count;
}
static struct device_attribute rfkill_dev_attrs[] = {
__ATTR(name, S_IRUGO, rfkill_name_show, NULL),
__ATTR(type, S_IRUGO, rfkill_type_show, NULL),
__ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
__ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
__ATTR_NULL
};
static void rfkill_release(struct device *dev)
{
struct rfkill *rfkill = to_rfkill(dev);
kfree(rfkill);
module_put(THIS_MODULE);
}
#ifdef CONFIG_PM
static int rfkill_suspend(struct device *dev, pm_message_t state)
{
struct rfkill *rfkill = to_rfkill(dev);
if (dev->power.power_state.event != state.event) {
if (state.event == PM_EVENT_SUSPEND) {
mutex_lock(&rfkill->mutex);
if (rfkill->state == RFKILL_STATE_ON)
rfkill->toggle_radio(rfkill->data,
RFKILL_STATE_OFF);
mutex_unlock(&rfkill->mutex);
}
dev->power.power_state = state;
}
return 0;
}
static int rfkill_resume(struct device *dev)
{
struct rfkill *rfkill = to_rfkill(dev);
if (dev->power.power_state.event != PM_EVENT_ON) {
mutex_lock(&rfkill->mutex);
if (rfkill->state == RFKILL_STATE_ON)
rfkill->toggle_radio(rfkill->data, RFKILL_STATE_ON);
mutex_unlock(&rfkill->mutex);
}
dev->power.power_state = PMSG_ON;
return 0;
}
#else
#define rfkill_suspend NULL
#define rfkill_resume NULL
#endif
static struct class rfkill_class = {
.name = "rfkill",
.dev_release = rfkill_release,
.dev_attrs = rfkill_dev_attrs,
.suspend = rfkill_suspend,
.resume = rfkill_resume,
};
static int rfkill_add_switch(struct rfkill *rfkill)
{
int retval;
retval = mutex_lock_interruptible(&rfkill_mutex);
if (retval)
return retval;
retval = rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type]);
if (retval)
goto out;
list_add_tail(&rfkill->node, &rfkill_list);
out:
mutex_unlock(&rfkill_mutex);
return retval;
}
static void rfkill_remove_switch(struct rfkill *rfkill)
{
mutex_lock(&rfkill_mutex);
list_del_init(&rfkill->node);
rfkill_toggle_radio(rfkill, RFKILL_STATE_OFF);
mutex_unlock(&rfkill_mutex);
}
/**
* rfkill_allocate - allocate memory for rfkill structure.
* @parent: device that has rf switch on it
* @type: type of the switch (wlan, bluetooth, irda)
*
* This function should be called by the network driver when it needs
* rfkill structure. Once the structure is allocated the driver shoud
* finish its initialization by setting name, private data, enable_radio
* and disable_radio methods and then register it with rfkill_register().
* NOTE: If registration fails the structure shoudl be freed by calling
* rfkill_free() otherwise rfkill_unregister() should be used.
*/
struct rfkill *rfkill_allocate(struct device *parent, enum rfkill_type type)
{
struct rfkill *rfkill;
struct device *dev;
rfkill = kzalloc(sizeof(struct rfkill), GFP_KERNEL);
if (!rfkill)
return NULL;
mutex_init(&rfkill->mutex);
INIT_LIST_HEAD(&rfkill->node);
rfkill->type = type;
dev = &rfkill->dev;
dev->class = &rfkill_class;
dev->parent = parent;
device_initialize(dev);
__module_get(THIS_MODULE);
return rfkill;
}
EXPORT_SYMBOL(rfkill_allocate);
/**
* rfkill_free - Mark rfkill structure for deletion
* @rfkill: rfkill structure to be destroyed
*
* Decrements reference count of rfkill structure so it is destoryed.
* Note that rfkill_free() should _not_ be called after rfkill_unregister().
*/
void rfkill_free(struct rfkill *rfkill)
{
if (rfkill)
put_device(&rfkill->dev);
}
EXPORT_SYMBOL(rfkill_free);
/**
* rfkill_register - Register a rfkill structure.
* @rfkill: rfkill structure to be registered
*
* This function should be called by the network driver when the rfkill
* structure needs to be registered. Immediately from registration the
* switch driver should be able to service calls to toggle_radio.
*/
int rfkill_register(struct rfkill *rfkill)
{
static atomic_t rfkill_no = ATOMIC_INIT(0);
struct device *dev = &rfkill->dev;
int error;
if (!rfkill->toggle_radio)
return -EINVAL;
error = rfkill_add_switch(rfkill);
if (error)
return error;
snprintf(dev->bus_id, sizeof(dev->bus_id),
"rfkill%ld", (long)atomic_inc_return(&rfkill_no) - 1);
error = device_add(dev);
if (error) {
rfkill_remove_switch(rfkill);
return error;
}
return 0;
}
EXPORT_SYMBOL(rfkill_register);
/**
* rfkill_unregister - Uegister a rfkill structure.
* @rfkill: rfkill structure to be unregistered
*
* This function should be called by the network driver during device
* teardown to destroy rfkill structure. Note that rfkill_free() should
* _not_ be called after rfkill_unregister().
*/
void rfkill_unregister(struct rfkill *rfkill)
{
device_del(&rfkill->dev);
rfkill_remove_switch(rfkill);
put_device(&rfkill->dev);
}
EXPORT_SYMBOL(rfkill_unregister);
/*
* Rfkill module initialization/deinitialization.
*/
static int __init rfkill_init(void)
{
int error;
int i;
for (i = 0; i < ARRAY_SIZE(rfkill_states); i++)
rfkill_states[i] = RFKILL_STATE_ON;
error = class_register(&rfkill_class);
if (error) {
printk(KERN_ERR "rfkill: unable to register rfkill class\n");
return error;
}
return 0;
}
static void __exit rfkill_exit(void)
{
class_unregister(&rfkill_class);
}
module_init(rfkill_init);
module_exit(rfkill_exit);
