Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759817AbWLCW2c (ORCPT ); Sun, 3 Dec 2006 17:28:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759818AbWLCW2c (ORCPT ); Sun, 3 Dec 2006 17:28:32 -0500 Received: from ug-out-1314.google.com ([66.249.92.168]:6988 "EHLO ug-out-1314.google.com") by vger.kernel.org with ESMTP id S1759790AbWLCW23 (ORCPT ); Sun, 3 Dec 2006 17:28:29 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:to:subject:date:user-agent:cc:references:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:message-id:from; b=B+vWRkmXYRMW1+CV7hKbzgHYroc8KXLyCtGggnMnNJdGWrPFKMuopv3GF/xYjfidDyrvdPFly3lIs8ss2qOSS3m9w5TxTUzcG1XeFEVCZr3JUGKJFF6PqU/ILyzPDL6qnMn4GsnnnWgKRg3U4NpjgNQoWJnKC53TxBns6zTUgfM= To: Arjan van de Ven Subject: Re: [RFC] rfkill - Add support for input key to control wireless radio Date: Sun, 3 Dec 2006 23:28:11 +0100 User-Agent: KMail/1.9.5 Cc: Dmitry Torokhov , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, John Linville , Jiri Benc , Lennart Poettering , Johannes Berg , Larry Finger References: <200612031936.34343.IvDoorn@gmail.com> <1165173618.3233.243.camel@laptopd505.fenrus.org> In-Reply-To: <1165173618.3233.243.camel@laptopd505.fenrus.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200612032328.12093.IvDoorn@gmail.com> From: Ivo van Doorn Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 28469 Lines: 1097 rfkill with the fixes as suggested by Arjan. - instead of a semaphore a mutex is now being used. - open_count changing is now locked by the mutex. Signed-off-by Ivo van Doorn --- diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig index ba0e88c..6986d59 100644 --- a/drivers/input/misc/Kconfig +++ b/drivers/input/misc/Kconfig @@ -79,4 +79,19 @@ config HP_SDC_RTC Say Y here if you want to support the built-in real time clock of the HP SDC controller. +config RFKILL + tristate "RF button support" + help + If you say yes here, the rfkill driver will be build + which allowed network devices to register their hardware + RF button which controls the radio state. This driver + will then create an input device for it. + + When the input device is not used, the rfkill driver + will make sure that when the RF button is pressed the radio + is enabled or disabled accordingly. When the input device + has been opened by the user this radio control will be left + to the user, and rfkill will only send the RF button status + change to userspace. + endif diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile index 415c491..e788a1b 100644 --- a/drivers/input/misc/Makefile +++ b/drivers/input/misc/Makefile @@ -11,3 +11,4 @@ obj-$(CONFIG_INPUT_UINPUT) += uinput.o obj-$(CONFIG_INPUT_WISTRON_BTNS) += wistron_btns.o obj-$(CONFIG_HP_SDC_RTC) += hp_sdc_rtc.o obj-$(CONFIG_INPUT_IXP4XX_BEEPER) += ixp4xx-beeper.o +obj-$(CONFIG_RFKILL) += rfkill.o diff --git a/drivers/input/misc/rfkill.c b/drivers/input/misc/rfkill.c new file mode 100644 index 0000000..4777d73 --- /dev/null +++ b/drivers/input/misc/rfkill.c @@ -0,0 +1,887 @@ +/* + Copyright (C) 2006 Ivo van Doorn + + 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 key support"); +MODULE_LICENSE("GPL"); + +/* + * rfkill key structure. + */ +struct rfkill_key { + /* + * For sysfs representation. + */ + struct class_device *cdev; + + /* + * Pointer to rfkill structure + * that was filled in by key driver. + */ + struct rfkill *rfkill; + + /* + * Pointer to type structure that this key belongs to. + */ + struct rfkill_type *type; + + /* + * Once key status change has been detected, the toggled + * field should be set to indicate a notification to + * user or driver should be performed. + */ + int toggled; + + /* + * Current state of the device radio, this state will + * change after the radio has actually been toggled since + * receiving the radio key event. + */ + int radio_status; + + /* + * Current status of the key which controls the radio, + * this value will change after the key state has changed + * after polling, or the key driver has send the new state + * manually. + */ + int key_status; + + /* + * Input device for this key, + * we also keep track of the number of + * times this input device is open. This + * is important for determining to whom we + * should report key events. + */ + struct input_dev *input; + unsigned int open_count; + + /* + * Key index number. + */ + unsigned int key_index; + + /* + * List head structure to be used + * to add this structure to the list. + */ + struct list_head entry; +}; + +/* + * rfkill key type structure. + */ +struct rfkill_type { + /* + * For sysfs representation. + */ + struct class_device *cdev; + + /* + * Name of this radio type. + */ + char *name; + + /* + * Key type identification. Value must be any + * in the key_type enum. + */ + unsigned int key_type; + + /* + * Number of registered keys of this type. + */ + unsigned int key_count; +}; + +/* + * rfkill master structure. + */ +struct rfkill_master { + /* + * For sysfs representation. + */ + struct class *class; + + /* + * All access to the master structure + * and its children (the keys) are protected + * by this key lock. + */ + struct mutex mutex; + + /* + * List of available key types. + */ + struct rfkill_type type[KEY_TYPE_MAX]; + + /* + * Total number of registered keys. + */ + unsigned int key_count; + + /* + * Number of keys that require polling + */ + unsigned int poll_required; + + /* + * List of rfkill_key structures. + */ + struct list_head key_list; + + /* + * Work structures for periodic polling, + * as well as the scheduled radio toggling. + */ + struct work_struct toggle_work; + struct work_struct poll_work; +}; + +/* + * We only need 1 single master interface, + * make this a global variable since we always need it. + */ +static struct rfkill_master *master; + +/* + * Send toggle event to key driver. + */ +static void rfkill_toggle_radio_driver(struct rfkill_key *key) +{ + struct rfkill *rfkill = key->rfkill; + + /* + * check what the current radio status is, and perform + * the correct action to toggle the radio. This will make + * sure the correct event happens when either the key driver + * of the user has requested to toggle this radio. + */ + if (!key->radio_status && rfkill->enable_radio) + rfkill->enable_radio(rfkill->data); + else if (key->radio_status && rfkill->disable_radio) + rfkill->disable_radio(rfkill->data); + + /* + * Independent of the presence of the enable_radio and + * disable_radio handler update the radio_status field. + * Note that this is valid, since if the key driver did + * not provide the 2 radio handlers, the driver is in + * charge of correctly setting the radio. This is usually + * done because the hardware will toggle the radio itself. + */ + key->radio_status = key->key_status; +} + +/* + * Send toggle event to userspace through the input device. + */ +static void rfkill_toggle_radio_input(struct rfkill_key *key) +{ + input_report_key(key->input, KEY_RFKILL, key->key_status); + input_sync(key->input); +} + +/* + * Loop through the list of registered keys and + * check if key if it has been toggled. + */ +static void rfkill_toggle_radio(void *data) +{ + struct rfkill_key *key; + + mutex_lock(&master->mutex); + + list_for_each_entry(key, &master->key_list, entry) { + + /* + * If this key hasn't been toggled by either + * the key driver or the user we can skip this key. + */ + if (!key->toggled) + continue; + + /* + * If the input device has been opened, all events + * should be send to userspace otherwise the key driver + * is supposed to handle the event. + */ + if (key->open_count) + rfkill_toggle_radio_input(key); + else + rfkill_toggle_radio_driver(key); + + /* + * Reset the toggled field to allow new toggle events. + */ + key->toggled = 0; + } + + mutex_unlock(&master->mutex); +} + +/* + * Check the new status of the key, and determine if the key has been toggled. + * This function can be called upon request by the device driver or userspace. + */ +static int rfkill_check_status(struct rfkill_key *key, int status) +{ + /* + * A key should be toggled if the current radio status does not + * match the requested status. This check is required instead of + * comparing it to the current key status since this function can + * be called on request of the user as well. The user is able to + * request a radio toggle to make sure the radio status will match + * the key status if the new key status has been reported to + * userspace only. + * As a safety measure, we won't toggle a key twice. + */ + if (key->radio_status != !!status && !key->toggled) { + key->toggled = 1; + return 1; + } + + return 0; +} + +/* + * Wrapper around the rfkill_check_status function, this may only + * be called from the device driver status events. Besides calling + * rfkill_check_status it will also update the key_status field. + */ +static int rfkill_check_key(struct rfkill_key *key, int status) +{ + /* + * Store the new key status value. + */ + key->key_status = !!status; + + /* + * The rest of the work should be done by rfkill_check_status. + */ + return rfkill_check_status(key->rfkill->key, status); +} + +/* + * Handler that is run frequently to determine the current status + * of all registered keys that require polling. + */ +static void rfkill_list_poll(void *data) +{ + struct rfkill_key *key; + struct rfkill *rfkill; + int status = 0; + + mutex_lock(&master->mutex); + + list_for_each_entry(key, &master->key_list, entry) { + rfkill = key->rfkill; + + /* + * If the poll handler has not been given + * the key driver should report events, + * so we can ignore this key now. + */ + if (!rfkill->poll) + continue; + + /* + * Poll radio state and check if a radio toggle + * has been requested by the key. + */ + if (rfkill_check_key(key, rfkill->poll(rfkill->data))) + status = 1; + } + + mutex_unlock(&master->mutex); + + /* + * A radio toggle has been requested, schedule the toggle work thread. + */ + if (status) + schedule_work(&master->toggle_work); + + /* + * Check if we need to rearm ourselves. + */ + if (master->poll_required) + schedule_delayed_work(&master->poll_work, RFKILL_POLL_DELAY); +} + +/* + * Function called by the key driver to report the new status + * of the key. + */ +void rfkill_report_event(struct rfkill *rfkill, int new_status) +{ + mutex_lock(&master->mutex); + + if (rfkill_check_key(rfkill->key, new_status)) + schedule_work(&master->toggle_work); + + mutex_unlock(&master->mutex); +} +EXPORT_SYMBOL_GPL(rfkill_report_event); + +/* + * Sysfs handler to release the data when sysfs is cleaning + * up all the garbage. This is done in a late state since the + * user could still be reading some of the files at the moment + * this key was removed. + * This method is being used for both rfkill_key as rfkill_type + * class devices. So be careful not to do anything structure + * specific. + */ +static void rfkill_class_device_release(struct class_device *cdev) +{ + kfree(class_get_devdata(cdev)); +} + +/* + * rfkill master sysfs creation. + */ +static int rfkill_master_sysfs_create(struct rfkill_master *master) +{ + master->class = class_create(THIS_MODULE, "rfkill"); + if (unlikely(!master->class || IS_ERR(master->class))) + return PTR_ERR(master->class); + + master->class->release = rfkill_class_device_release; + + return 0; +} + +/* + * rfkill master sysfs destroy. + */ +static void rfkill_master_sysfs_release(struct rfkill_master *master) +{ + class_destroy(master->class); +} + +/* + * rfkill type sysfs creation. + */ +static int rfkill_type_sysfs_create(struct rfkill_master *master, + struct rfkill_type *type) +{ + type->cdev = class_device_create(master->class, NULL, type->key_type, + NULL, type->name); + if (unlikely(!type->cdev || IS_ERR(type->cdev))) + return PTR_ERR(type->cdev); + + return 0; +} + +static void rfkill_type_sysfs_release(struct rfkill_type *type) +{ + class_device_destroy(type->cdev->class, type->key_type); +} + +/* + * rfkill key attribute to display the current key status. + */ +static ssize_t rfkill_key_status_show(struct class_device *cdev, char *buf) +{ + struct rfkill_key *key = class_get_devdata(cdev); + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + return sprintf(buf, "%d", key->key_status); +} + +/* + * rfkill key attribute to change the current radio status. + */ +static ssize_t rfkill_key_status_store(struct class_device *cdev, + const char *buf, size_t count) +{ + struct rfkill_key *key = class_get_devdata(cdev); + int status = simple_strtoul(buf, NULL, 0); + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + mutex_lock(&master->mutex); + + /* + * Check if this new status implies that the radio + * should be toggled to the correct state. + */ + if (rfkill_check_status(key, status)) + schedule_work(&master->toggle_work); + + mutex_unlock(&master->mutex); + + return count; +} + +static struct class_device_attribute cdev_attr_key_status = + __ATTR(status, S_IRUGO | S_IWUGO, + rfkill_key_status_show, rfkill_key_status_store); + +/* + * rfkill key sysfs creation. + */ +static int rfkill_key_sysfs_create(struct rfkill_master *master, + struct rfkill_key *key) +{ + int status; + + key->cdev = class_device_create(master->class, key->type->cdev, + KEY_TYPE_MAX + key->key_index, + key->rfkill->dev, + "key%d", key->key_index); + if (unlikely(!key->cdev || IS_ERR(key->cdev))) + return PTR_ERR(key->cdev); + + /* + * Create the sysfs files. + */ + status = class_device_create_file(key->cdev, &cdev_attr_key_status); + if (unlikely(status)) + goto exit; + + /* + * The key belongs to the device structure the key driver + * has given us a reference to. But besides that device + * this key also belongs to the input device that has been + * created. We should create the link to that entry manually. + */ + status = sysfs_create_link(&key->cdev->kobj, &key->input->cdev.kobj, + "idev"); + if (unlikely(status)) + goto exit_file; + + return 0; + +exit_file: + class_device_remove_file(key->cdev, &cdev_attr_key_status); + +exit: + class_device_destroy(master->class, KEY_TYPE_MAX + key->key_index); + + return status; +} + +static void rfkill_key_sysfs_release(struct rfkill_key *key) +{ + sysfs_remove_link(&key->cdev->kobj, "idev"); + class_device_remove_file(key->cdev, &cdev_attr_key_status); + class_device_destroy(master->class, KEY_TYPE_MAX + key->key_index); +} + +/* + * Handlers to enable or close the input device. + * These handlers only have to increase or decrease the open_count, + * this counter will automatically make sure key events will be + * send to the correct location (userspace or key driver). + */ +static int rfkill_open(struct input_dev *dev) +{ + mutex_lock(&master->mutex); + + ((struct rfkill_key*)(dev->private))->open_count++; + + mutex_unlock(&master->mutex); + return 0; +} + +static void rfkill_close(struct input_dev *dev) +{ + mutex_lock(&master->mutex); + + ((struct rfkill_key*)(dev->private))->open_count--; + + mutex_unlock(&master->mutex); +} + +/* + * Input device initialization handler. + */ +static struct input_dev* rfkill_register_input(struct rfkill_key *key) +{ + struct input_dev *input; + int status; + char *name; + char *phys; + + input = input_allocate_device(); + if (unlikely(!input)) + return NULL; + + /* + * Link the private data to rfkill structure. + */ + input->private = key; + + /* + * Allocate the strings for the input device names. + */ + name = kasprintf(GFP_KERNEL, "rfkill key%d: %s", + key->key_index, key->rfkill->dev_name); + phys = kasprintf(GFP_KERNEL, "rfkill/%s/key%d", + key->type->name, key->key_index); + + if (!name || !phys) + goto exit; + + input->name = name; + input->phys = phys; + + /* + * Initialize the input_id structure. + */ + input->id.bustype = BUS_HOST; + input->id.vendor = 0x0001; + input->id.product = 0x0001; + input->id.version = 0x0001; + + input->evbit[0] = BIT(EV_KEY); + set_bit(KEY_RFKILL, input->keybit); + + input->open = rfkill_open; + input->close = rfkill_close; + + status = input_register_device(input); + if (status) + goto exit; + + return input; + +exit: + input_free_device(input); + + kfree(name); + kfree(phys); + + return NULL; +} + +/* + * Input device deinitialization handler. + */ +static void rfkill_deregister_input(struct rfkill_key *key) +{ + const char *name; + const char *phys; + + /* + * The name and phys fields have been allocated + * using kasprintf, this means they have to be + * freed seperately. + */ + name = key->input->name; + phys = key->input->phys; + + input_unregister_device(key->input); + kfree(name); + kfree(phys); +} + +/* + * Rfkill key initialization/deinitialization. + * These methods should only be called with the mutex held. + */ +static struct rfkill_key* rfkill_key_init(struct rfkill *rfkill, int status) +{ + struct rfkill_key *key; + + key = kzalloc(sizeof(struct rfkill_key), GFP_KERNEL); + if (unlikely(!key)) + return NULL; + + /* + * Initialize all variables. + */ + key->rfkill = rfkill; + rfkill->key = key; + key->type = &master->type[rfkill->key_type]; + key->toggled = 0; + key->radio_status = status; + key->key_status = status; + key->key_index = master->key_count++; + INIT_LIST_HEAD(&key->entry); + + /* + * Create input device. + */ + key->input = rfkill_register_input(key); + if (!key->input) + goto exit; + + /* + * Create sysfs entry. + */ + if (rfkill_key_sysfs_create(master, key)) + goto exit; + + return key; + +exit: + rfkill_deregister_input(key); + rfkill->key = NULL; + kfree(key); + return NULL; +} + +static void rfkill_key_deinit(struct rfkill_key *key) +{ + if (key) { + rfkill_key_sysfs_release(key); + rfkill_deregister_input(key); + } +} + +/* + * Rfkill type handler to check if the sysfs entries should + * be created or removed based on the number of registered keys. + */ +static int rfkill_add_type_key(struct rfkill_type *type) +{ + int status; + + if (type->key_count) { + type->key_count++; + return 0; + } + + status = rfkill_type_sysfs_create(master, type); + if (status) + return status; + + type->key_count = 1; + return 0; +} + +static void rfkill_del_type_key(struct rfkill_type *type) +{ + if (!--type->key_count) + rfkill_type_sysfs_release(type); +} + +/* + * Function called by the key driver when the rfkill structure + * needs to be registered. + */ +int rfkill_register_key(struct rfkill *rfkill, int init_status) +{ + struct rfkill_type *type = &master->type[rfkill->key_type]; + struct rfkill_key *key; + int status; + + if (!rfkill) + return -EINVAL; + + if (rfkill->key_type >= KEY_TYPE_MAX) + return -EINVAL; + + /* + * Increase module use count to prevent this + * module to be unloaded while there are still + * registered keys. + */ + if (!try_module_get(THIS_MODULE)) + return -EBUSY; + + mutex_lock(&master->mutex); + + /* + * Initialize key, and if required the type. + */ + status = rfkill_add_type_key(type); + if (status) + goto exit; + + key = rfkill_key_init(rfkill, init_status); + if (!key) { + status = -ENOMEM; + goto exit_type; + } + + /* + * Add key to our list. + */ + list_add(&key->entry, &master->key_list); + + /* + * Check if we need polling, and if we do + * increase the poll required counter and check + * if we weren't polling yet. + */ + if (rfkill->poll && !master->poll_required++) + schedule_delayed_work(&master->poll_work, RFKILL_POLL_DELAY); + + mutex_unlock(&master->mutex); + + return 0; + +exit_type: + rfkill_del_type_key(type); + +exit: + mutex_unlock(&master->mutex); + module_put(THIS_MODULE); + + return status; +} +EXPORT_SYMBOL_GPL(rfkill_register_key); + +/* + * Function called by the key driver when the rfkill structure + * needs to be deregistered. + */ +int rfkill_deregister_key(struct rfkill *rfkill) +{ + struct rfkill_type *type; + + if (!rfkill || !rfkill->key) + return -EINVAL; + + mutex_lock(&master->mutex); + + /* + * Cancel delayed work if this is the last key + * that requires polling. It is not bad if + * if the workqueue is still running, + * the workqueue won't rearm itself since the + * poll_required variable has been set. + * and we have protected the list with a semaphore. + */ + if (rfkill->poll && !--master->poll_required) + cancel_delayed_work(&master->poll_work); + + /* + * Delete the rfkill structure to the list. + */ + list_del(&rfkill->key->entry); + + /* + * Deinitialize key. + */ + type = rfkill->key->type; + rfkill_key_deinit(rfkill->key); + rfkill_del_type_key(type); + + mutex_unlock(&master->mutex); + + /* + * rfkill entry has been removed, + * decrease module use count. + */ + module_put(THIS_MODULE); + + return 0; +} +EXPORT_SYMBOL_GPL(rfkill_deregister_key); + +/* + * Rfkill type initialization. + */ +static void rfkill_type_init(unsigned int key_type, char *name) +{ + struct rfkill_type *type = &master->type[key_type]; + + /* + * Initialize all variables. + */ + type->name = name; + type->key_type = key_type; + type->key_count = 0; +} + +/* + * Rfkill master initialization/deinitialization. + */ +static int rfkill_master_init(void) +{ + int status; + + master = kzalloc(sizeof(struct rfkill_master), GFP_KERNEL); + if (unlikely(!master)) + return -ENOMEM; + + /* + * Initialize all variables. + */ + mutex_init(&master->mutex); + INIT_LIST_HEAD(&master->key_list); + INIT_WORK(&master->toggle_work, &rfkill_toggle_radio, NULL); + INIT_WORK(&master->poll_work, &rfkill_list_poll, NULL); + + /* + * Initialize all type structures. + */ + rfkill_type_init(KEY_TYPE_WIFI, "wifi"); + rfkill_type_init(KEY_TYPE_BlUETOOTH, "bluetooth"); + rfkill_type_init(KEY_TYPE_IRDA, "irda"); + + /* + * Create sysfs entry. + */ + status = rfkill_master_sysfs_create(master); + if (status) { + kfree(master); + master = NULL; + return status; + } + + return 0; +} + +static void rfkill_master_deinit(void) +{ + if (master) { + rfkill_master_sysfs_release(master); + kfree(master); + master = NULL; + } +} + +/* + * Module initialization/deinitialization. + */ +static int __init rfkill_init(void) +{ + printk(KERN_INFO "Loading rfkill driver.\n"); + + return rfkill_master_init(); +} + +static void __exit rfkill_exit(void) +{ + rfkill_master_deinit(); + + printk(KERN_INFO "Unloading rfkill driver.\n"); +} + +module_init(rfkill_init); +module_exit(rfkill_exit); diff --git a/include/linux/input.h b/include/linux/input.h index c38507b..1b44108 100644 --- a/include/linux/input.h +++ b/include/linux/input.h @@ -491,6 +491,7 @@ struct input_absinfo { #define KEY_DIGITS 0x19d #define KEY_TEEN 0x19e #define KEY_TWEN 0x19f +#define KEY_RFKILL 0x1a0 #define KEY_DEL_EOL 0x1c0 #define KEY_DEL_EOS 0x1c1 diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h new file mode 100644 index 0000000..a455548 --- /dev/null +++ b/include/linux/rfkill.h @@ -0,0 +1,140 @@ +/* + Copyright (C) 2006 Ivo van Doorn + + 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. + */ + +/* + RF button support + Laptops are quite often equiped with a RF key to enable or + disable the radio of the wireless device attached to that key. + This wireless device usually is an integrated wireless network device, + infrared or bluetooth device. + Some of these devices will disable the radio automatically when the + RF key has been pressed, while other devices need to be polled + for the RF key status, and leave the action to be taken up to the + driver for that particular device. + But in all cases the only interface that will have its radio disabled + will be the device that has the RF key attached to it. It could however + be desired that userspace performs this disabling of the radios in case + more things than just disabling a single radio is desired. + + The rfkill driver will contain a list of all devices with a RF button, + and hardware drivers need to register their hardware to the rfkill + interface. Rfkill will then take care of everything. If the RF key + requires polling to obtain the status this will be handled by rfkill. + If the RF key does not require polling but sends for example interrupts, + the hardware driver can report the change of status to rfkill, without + having to do any other action. + Once the status of the key has changed and the hardware does not + automatically enable or disable the radio rfkill provides the + interface to do this correctly. + + For each registered hardware button an input device will be created. + If this input device has been opened by the user, rfkill will send a + signal to userspace instead of the hardware about the new button + status. This will allow userpace to perform the correct steps + in order to bring down all interfaces. + */ + +#ifndef RFKILL_H +#define RFKILL_H + +#include + +#define RFKILL_POLL_DELAY ( HZ / 10 ) + +enum key_type { + KEY_TYPE_WIFI = 0, + KEY_TYPE_BlUETOOTH = 1, + KEY_TYPE_IRDA = 2, + KEY_TYPE_MAX = 3, +}; + +/** + * struct rfkill - rfkill button control structure. + * + * @dev_name: Name of the interface. This will become the name + * of the input device which will be created for this button. + * @dev: Pointer to the device structure to which this button belongs to. + * @data: Pointer to the RF button drivers private data which will be + * passed along with the radio and polling handlers. + * @poll(void *data): Optional handler which will frequently be + * called to determine the current status of the RF button. + * @enable_radio(void *data): Optional handler to enable the radio + * once the RF button has been pressed and the hardware does enable + * the radio automaticly. + * @disable_radio(void *data): Optional handler to disable the radio + * once the RF button has been pressed and the hardware does disable + * the radio automaticly. + * @key_type: Radio type which the button controls, the value stored + * here should be a value from enum key_type. + * @key: Internal pointer that should not be touched by key driver. + * + * This structure can be used by a key driver to register the key + * to the rfkill driver in order to take control of the reporting + * to userspace or handling of radio status. + */ +struct rfkill { + const char *dev_name; + + struct device *dev; + + void *data; + int (*poll)(void *data); + void (*enable_radio)(void *data); + void (*disable_radio)(void *data); + + unsigned int key_type; + + struct rfkill_key *key; +}; + +/** + * rfkill_register_key - Deregister a previously registered rfkill structre. + * @rfkill: rfkill structure to be deregistered + * @init_status: initial status of the key at the time this function is called + * + * This function should be called by the key driver when the rfkill structure + * needs to be registered. Immediately from registration the key driver + * should be able to receive calls through the poll, enable_radio and + * disable_radio handlers if those were registered. + */ +int rfkill_register_key(struct rfkill *rfkill, int init_status); + +/** + * rfkill_deregister_key - Deregister a previously registered rfkill structre. + * @rfkill: rfkill structure to be deregistered + * + * This function should be called by the key driver when the rfkill structure + * needs to be deregistered. This function may only be called if it was + * previously registered with rfkill_register_key. + */ +int rfkill_deregister_key(struct rfkill *rfkill); + +/** + * rfkill_report_event - Report change in key status to rfkill handler. + * @rfkill: rfkill structure registered by key driver + * @new_status: new key status + * + * This function should be called by the key driver if it has not provided + * a poll handler with rfkill. As soon as the key driver has determined + * the status of the key has changed it should report the new status + * through this function. + */ +void rfkill_report_event(struct rfkill *rfkill, int new_status); + +#endif /* RFKILL_H */ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/