linux/net/rfkill/rfkill.c
Ivo van Doorn c81de6addb [RFKILL]: Make state sysfs writable
The rfkill state Sysfs attribute should be made writable,
we already pass the argument for the store handler,
so we only need to update the permissions flag.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-18 15:38:03 -07:00

408 lines
9.4 KiB
C

/*
* 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);