From: Ivo van Doorn Date: Mon, 7 May 2007 07:34:20 +0000 (-0700) Subject: [NET]: rfkill: add support for input key to control wireless radio X-Git-Tag: v2.6.22-rc1~822^2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cf4328cd949c2086091c62c5685f1580fe9b55e4;p=linux-2.6 [NET]: rfkill: add support for input key to control wireless radio The RF kill patch that provides infrastructure for implementing switches controlling radio states on various network and other cards. [dtor@insightbb.com: address review comments] [akpm@linux-foundation.org: cleanups, build fixes] Signed-off-by: Ivo van Doorn Signed-off-by: Andrew Morton Signed-off-by: Dmitry Torokhov Signed-off-by: David S. Miller --- diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h new file mode 100644 index 0000000000..7c1ffbab78 --- /dev/null +++ b/include/linux/rfkill.h @@ -0,0 +1,89 @@ +#ifndef __RFKILL_H +#define __RFKILL_H + +/* + * 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 +#include +#include +#include +#include + +/** + * enum rfkill_type - type of rfkill switch. + * RFKILL_TYPE_WLAN: switch is no a Wireless network devices. + * RFKILL_TYPE_BlUETOOTH: switch is on a bluetooth device. + * RFKILL_TYPE_IRDA: switch is on an infrared devices. + */ +enum rfkill_type { + RFKILL_TYPE_WLAN = 0, + RFKILL_TYPE_BLUETOOTH = 1, + RFKILL_TYPE_IRDA = 2, + RFKILL_TYPE_MAX = 3, +}; + +enum rfkill_state { + RFKILL_STATE_OFF = 0, + RFKILL_STATE_ON = 1, +}; + +/** + * struct rfkill - rfkill control structure. + * @name: Name of the switch. + * @type: Radio type which the button controls, the value stored + * here should be a value from enum rfkill_type. + * @state: State of the switch (on/off). + * @user_claim: Set when the switch is controlled exlusively by userspace. + * @mutex: Guards switch state transitions + * @data: Pointer to the RF button drivers private data which will be + * passed along when toggling radio state. + * @toggle_radio(): Mandatory handler to control state of the radio. + * @dev: Device structure integrating the switch into device tree. + * @node: Used to place switch into list of all switches known to the + * the system. + * + * This structure represents a RF switch located on a network device. + */ +struct rfkill { + char *name; + enum rfkill_type type; + + enum rfkill_state state; + bool user_claim; + + struct mutex mutex; + + void *data; + int (*toggle_radio)(void *data, enum rfkill_state state); + + struct device dev; + struct list_head node; +}; +#define to_rfkill(d) container_of(d, struct rfkill, dev) + +struct rfkill *rfkill_allocate(struct device *parent, enum rfkill_type type); +void rfkill_free(struct rfkill *rfkill); +int rfkill_register(struct rfkill *rfkill); +void rfkill_unregister(struct rfkill *rfkill); + +void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state); + +#endif /* RFKILL_H */ diff --git a/net/Kconfig b/net/Kconfig index 5b22278139..caeacd1665 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -225,6 +225,8 @@ source "net/ieee80211/Kconfig" endmenu +source "net/rfkill/Kconfig" + endif # if NET endmenu # Networking diff --git a/net/Makefile b/net/Makefile index 9fdb60c2e4..34e5b2d7f8 100644 --- a/net/Makefile +++ b/net/Makefile @@ -51,6 +51,7 @@ obj-$(CONFIG_IEEE80211) += ieee80211/ obj-$(CONFIG_TIPC) += tipc/ obj-$(CONFIG_NETLABEL) += netlabel/ obj-$(CONFIG_IUCV) += iucv/ +obj-$(CONFIG_RFKILL) += rfkill/ ifeq ($(CONFIG_NET),y) obj-$(CONFIG_SYSCTL) += sysctl_net.o diff --git a/net/rfkill/Kconfig b/net/rfkill/Kconfig new file mode 100644 index 0000000000..8b31759ee8 --- /dev/null +++ b/net/rfkill/Kconfig @@ -0,0 +1,24 @@ +# +# RF switch subsystem configuration +# +menuconfig RFKILL + tristate "RF switch subsystem support" + help + Say Y here if you want to have control over RF switches + found on many WiFi, Bluetooth and IRDA cards. + + To compile this driver as a module, choose M here: the + module will be called rfkill. + +config RFKILL_INPUT + tristate "Input layer to RF switch connector" + depends on RFKILL && INPUT + help + Say Y here if you want kernel automatically toggle state + of RF switches on and off when user presses appropriate + button or a key on the keyboard. Without this module you + need a some kind of userspace application to control + state of the switches. + + To compile this driver as a module, choose M here: the + module will be called rfkill-input. diff --git a/net/rfkill/Makefile b/net/rfkill/Makefile new file mode 100644 index 0000000000..b38c430be0 --- /dev/null +++ b/net/rfkill/Makefile @@ -0,0 +1,6 @@ +# +# Makefile for the RF switch subsystem. +# + +obj-$(CONFIG_RFKILL) += rfkill.o +obj-$(CONFIG_RFKILL_INPUT) += rfkill-input.o diff --git a/net/rfkill/rfkill-input.c b/net/rfkill/rfkill-input.c new file mode 100644 index 0000000000..e5c840c302 --- /dev/null +++ b/net/rfkill/rfkill-input.c @@ -0,0 +1,174 @@ +/* + * Input layer to RF Kill interface connector + * + * 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 version 2 as published + * by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Dmitry Torokhov "); +MODULE_DESCRIPTION("Input layer to RF switch connector"); +MODULE_LICENSE("GPL"); + +struct rfkill_task { + struct work_struct work; + enum rfkill_type type; + struct mutex mutex; /* ensures that task is serialized */ + spinlock_t lock; /* for accessing last and desired state */ + unsigned long last; /* last schedule */ + enum rfkill_state desired_state; /* on/off */ + enum rfkill_state current_state; /* on/off */ +}; + +static void rfkill_task_handler(struct work_struct *work) +{ + struct rfkill_task *task = container_of(work, struct rfkill_task, work); + enum rfkill_state state; + + mutex_lock(&task->mutex); + + /* + * Use temp variable to fetch desired state to keep it + * consistent even if rfkill_schedule_toggle() runs in + * another thread or interrupts us. + */ + state = task->desired_state; + + if (state != task->current_state) { + rfkill_switch_all(task->type, state); + task->current_state = state; + } + + mutex_unlock(&task->mutex); +} + +static void rfkill_schedule_toggle(struct rfkill_task *task) +{ + unsigned int flags; + + spin_lock_irqsave(&task->lock, flags); + + if (time_after(jiffies, task->last + msecs_to_jiffies(200))) { + task->desired_state = !task->desired_state; + task->last = jiffies; + schedule_work(&task->work); + } + + spin_unlock_irqrestore(&task->lock, flags); +} + +#define DEFINE_RFKILL_TASK(n, t) \ + struct rfkill_task n = { \ + .work = __WORK_INITIALIZER(n.work, \ + rfkill_task_handler), \ + .type = t, \ + .mutex = __MUTEX_INITIALIZER(n.mutex), \ + .lock = __SPIN_LOCK_UNLOCKED(n.lock), \ + .desired_state = RFKILL_STATE_ON, \ + .current_state = RFKILL_STATE_ON, \ + } + +static DEFINE_RFKILL_TASK(rfkill_wlan, RFKILL_TYPE_WLAN); +static DEFINE_RFKILL_TASK(rfkill_bt, RFKILL_TYPE_BLUETOOTH); + +static void rfkill_event(struct input_handle *handle, unsigned int type, + unsigned int code, int down) +{ + if (type == EV_KEY && down == 1) { + switch (code) { + case KEY_WLAN: + rfkill_schedule_toggle(&rfkill_wlan); + break; + case KEY_BLUETOOTH: + rfkill_schedule_toggle(&rfkill_bt); + break; + default: + break; + } + } +} + +static int rfkill_connect(struct input_handler *handler, struct input_dev *dev, + const struct input_device_id *id) +{ + struct input_handle *handle; + int error; + + handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL); + if (!handle) + return -ENOMEM; + + handle->dev = dev; + handle->handler = handler; + handle->name = "rfkill"; + + error = input_register_handle(handle); + if (error) + goto err_free_handle; + + error = input_open_device(handle); + if (error) + goto err_unregister_handle; + + return 0; + + err_unregister_handle: + input_unregister_handle(handle); + err_free_handle: + kfree(handle); + return error; +} + +static void rfkill_disconnect(struct input_handle *handle) +{ + input_close_device(handle); + input_unregister_handle(handle); + kfree(handle); +} + +static const struct input_device_id rfkill_ids[] = { + { + .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, + .evbit = { BIT(EV_KEY) }, + .keybit = { [LONG(KEY_WLAN)] = BIT(KEY_WLAN) }, + }, + { + .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, + .evbit = { BIT(EV_KEY) }, + .keybit = { [LONG(KEY_BLUETOOTH)] = BIT(KEY_BLUETOOTH) }, + }, + { } +}; + +static struct input_handler rfkill_handler = { + .event = rfkill_event, + .connect = rfkill_connect, + .disconnect = rfkill_disconnect, + .name = "rfkill", + .id_table = rfkill_ids, +}; + +static int __init rfkill_handler_init(void) +{ + return input_register_handler(&rfkill_handler); +} + +static void __exit rfkill_handler_exit(void) +{ + input_unregister_handler(&rfkill_handler); + flush_scheduled_work(); +} + +module_init(rfkill_handler_init); +module_exit(rfkill_handler_exit); diff --git a/net/rfkill/rfkill.c b/net/rfkill/rfkill.c new file mode 100644 index 0000000000..a973603e38 --- /dev/null +++ b/net/rfkill/rfkill.c @@ -0,0 +1,407 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Ivo van Doorn "); +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, 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);