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author | Johannes Berg <johannes@sipsolutions.net> | 2009-06-02 13:01:37 +0200 |
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committer | John W. Linville <linville@tuxdriver.com> | 2009-06-03 14:06:13 -0400 |
commit | 19d337dff95cbf76edd3ad95c0cee2732c3e1ec5 (patch) | |
tree | 33326eeb09cb9664cc8427a5dc7cd2b08b5a57c3 /net/rfkill/input.c | |
parent | 0f6399c4c525b518644a9b09f8d6fb125a418c4d (diff) | |
download | linux-19d337dff95cbf76edd3ad95c0cee2732c3e1ec5.tar.gz linux-19d337dff95cbf76edd3ad95c0cee2732c3e1ec5.tar.bz2 linux-19d337dff95cbf76edd3ad95c0cee2732c3e1ec5.zip |
rfkill: rewrite
This patch completely rewrites the rfkill core to address
the following deficiencies:
* all rfkill drivers need to implement polling where necessary
rather than having one central implementation
* updating the rfkill state cannot be done from arbitrary
contexts, forcing drivers to use schedule_work and requiring
lots of code
* rfkill drivers need to keep track of soft/hard blocked
internally -- the core should do this
* the rfkill API has many unexpected quirks, for example being
asymmetric wrt. alloc/free and register/unregister
* rfkill can call back into a driver from within a function the
driver called -- this is prone to deadlocks and generally
should be avoided
* rfkill-input pointlessly is a separate module
* drivers need to #ifdef rfkill functions (unless they want to
depend on or select RFKILL) -- rfkill should provide inlines
that do nothing if it isn't compiled in
* the rfkill structure is not opaque -- drivers need to initialise
it correctly (lots of sanity checking code required) -- instead
force drivers to pass the right variables to rfkill_alloc()
* the documentation is hard to read because it always assumes the
reader is completely clueless and contains way TOO MANY CAPS
* the rfkill code needlessly uses a lot of locks and atomic
operations in locked sections
* fix LED trigger to actually change the LED when the radio state
changes -- this wasn't done before
Tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> [thinkpad]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'net/rfkill/input.c')
-rw-r--r-- | net/rfkill/input.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/net/rfkill/input.c b/net/rfkill/input.c new file mode 100644 index 000000000000..a7295ad5f9cb --- /dev/null +++ b/net/rfkill/input.c @@ -0,0 +1,342 @@ +/* + * Input layer to RF Kill interface connector + * + * Copyright (c) 2007 Dmitry Torokhov + * Copyright 2009 Johannes Berg <johannes@sipsolutions.net> + * + * 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. + * + * If you ever run into a situation in which you have a SW_ type rfkill + * input device, then you can revive code that was removed in the patch + * "rfkill-input: remove unused code". + */ + +#include <linux/input.h> +#include <linux/slab.h> +#include <linux/workqueue.h> +#include <linux/init.h> +#include <linux/rfkill.h> +#include <linux/sched.h> + +#include "rfkill.h" + +enum rfkill_input_master_mode { + RFKILL_INPUT_MASTER_UNLOCK = 0, + RFKILL_INPUT_MASTER_RESTORE = 1, + RFKILL_INPUT_MASTER_UNBLOCKALL = 2, + NUM_RFKILL_INPUT_MASTER_MODES +}; + +/* Delay (in ms) between consecutive switch ops */ +#define RFKILL_OPS_DELAY 200 + +static enum rfkill_input_master_mode rfkill_master_switch_mode = + RFKILL_INPUT_MASTER_UNBLOCKALL; +module_param_named(master_switch_mode, rfkill_master_switch_mode, uint, 0); +MODULE_PARM_DESC(master_switch_mode, + "SW_RFKILL_ALL ON should: 0=do nothing (only unlock); 1=restore; 2=unblock all"); + +static spinlock_t rfkill_op_lock; +static bool rfkill_op_pending; +static unsigned long rfkill_sw_pending[BITS_TO_LONGS(NUM_RFKILL_TYPES)]; +static unsigned long rfkill_sw_state[BITS_TO_LONGS(NUM_RFKILL_TYPES)]; + +enum rfkill_sched_op { + RFKILL_GLOBAL_OP_EPO = 0, + RFKILL_GLOBAL_OP_RESTORE, + RFKILL_GLOBAL_OP_UNLOCK, + RFKILL_GLOBAL_OP_UNBLOCK, +}; + +static enum rfkill_sched_op rfkill_master_switch_op; +static enum rfkill_sched_op rfkill_op; + +static void __rfkill_handle_global_op(enum rfkill_sched_op op) +{ + unsigned int i; + + switch (op) { + case RFKILL_GLOBAL_OP_EPO: + rfkill_epo(); + break; + case RFKILL_GLOBAL_OP_RESTORE: + rfkill_restore_states(); + break; + case RFKILL_GLOBAL_OP_UNLOCK: + rfkill_remove_epo_lock(); + break; + case RFKILL_GLOBAL_OP_UNBLOCK: + rfkill_remove_epo_lock(); + for (i = 0; i < NUM_RFKILL_TYPES; i++) + rfkill_switch_all(i, false); + break; + default: + /* memory corruption or bug, fail safely */ + rfkill_epo(); + WARN(1, "Unknown requested operation %d! " + "rfkill Emergency Power Off activated\n", + op); + } +} + +static void __rfkill_handle_normal_op(const enum rfkill_type type, + const bool complement) +{ + bool blocked; + + blocked = rfkill_get_global_sw_state(type); + if (complement) + blocked = !blocked; + + rfkill_switch_all(type, blocked); +} + +static void rfkill_op_handler(struct work_struct *work) +{ + unsigned int i; + bool c; + + spin_lock_irq(&rfkill_op_lock); + do { + if (rfkill_op_pending) { + enum rfkill_sched_op op = rfkill_op; + rfkill_op_pending = false; + memset(rfkill_sw_pending, 0, + sizeof(rfkill_sw_pending)); + spin_unlock_irq(&rfkill_op_lock); + + __rfkill_handle_global_op(op); + + spin_lock_irq(&rfkill_op_lock); + + /* + * handle global ops first -- during unlocked period + * we might have gotten a new global op. + */ + if (rfkill_op_pending) + continue; + } + + if (rfkill_is_epo_lock_active()) + continue; + + for (i = 0; i < NUM_RFKILL_TYPES; i++) { + if (__test_and_clear_bit(i, rfkill_sw_pending)) { + c = __test_and_clear_bit(i, rfkill_sw_state); + spin_unlock_irq(&rfkill_op_lock); + + __rfkill_handle_normal_op(i, c); + + spin_lock_irq(&rfkill_op_lock); + } + } + } while (rfkill_op_pending); + spin_unlock_irq(&rfkill_op_lock); +} + +static DECLARE_DELAYED_WORK(rfkill_op_work, rfkill_op_handler); +static unsigned long rfkill_last_scheduled; + +static unsigned long rfkill_ratelimit(const unsigned long last) +{ + const unsigned long delay = msecs_to_jiffies(RFKILL_OPS_DELAY); + return (time_after(jiffies, last + delay)) ? 0 : delay; +} + +static void rfkill_schedule_ratelimited(void) +{ + if (delayed_work_pending(&rfkill_op_work)) + return; + schedule_delayed_work(&rfkill_op_work, + rfkill_ratelimit(rfkill_last_scheduled)); + rfkill_last_scheduled = jiffies; +} + +static void rfkill_schedule_global_op(enum rfkill_sched_op op) +{ + unsigned long flags; + + spin_lock_irqsave(&rfkill_op_lock, flags); + rfkill_op = op; + rfkill_op_pending = true; + if (op == RFKILL_GLOBAL_OP_EPO && !rfkill_is_epo_lock_active()) { + /* bypass the limiter for EPO */ + cancel_delayed_work(&rfkill_op_work); + schedule_delayed_work(&rfkill_op_work, 0); + rfkill_last_scheduled = jiffies; + } else + rfkill_schedule_ratelimited(); + spin_unlock_irqrestore(&rfkill_op_lock, flags); +} + +static void rfkill_schedule_toggle(enum rfkill_type type) +{ + unsigned long flags; + + if (rfkill_is_epo_lock_active()) + return; + + spin_lock_irqsave(&rfkill_op_lock, flags); + if (!rfkill_op_pending) { + __set_bit(type, rfkill_sw_pending); + __change_bit(type, rfkill_sw_state); + rfkill_schedule_ratelimited(); + } + spin_unlock_irqrestore(&rfkill_op_lock, flags); +} + +static void rfkill_schedule_evsw_rfkillall(int state) +{ + if (state) + rfkill_schedule_global_op(rfkill_master_switch_op); + else + rfkill_schedule_global_op(RFKILL_GLOBAL_OP_EPO); +} + +static void rfkill_event(struct input_handle *handle, unsigned int type, + unsigned int code, int data) +{ + if (type == EV_KEY && data == 1) { + switch (code) { + case KEY_WLAN: + rfkill_schedule_toggle(RFKILL_TYPE_WLAN); + break; + case KEY_BLUETOOTH: + rfkill_schedule_toggle(RFKILL_TYPE_BLUETOOTH); + break; + case KEY_UWB: + rfkill_schedule_toggle(RFKILL_TYPE_UWB); + break; + case KEY_WIMAX: + rfkill_schedule_toggle(RFKILL_TYPE_WIMAX); + break; + } + } else if (type == EV_SW && code == SW_RFKILL_ALL) + rfkill_schedule_evsw_rfkillall(data); +} + +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"; + + /* causes rfkill_start() to be called */ + 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_start(struct input_handle *handle) +{ + /* + * Take event_lock to guard against configuration changes, we + * should be able to deal with concurrency with rfkill_event() + * just fine (which event_lock will also avoid). + */ + spin_lock_irq(&handle->dev->event_lock); + + if (test_bit(EV_SW, handle->dev->evbit) && + test_bit(SW_RFKILL_ALL, handle->dev->swbit)) + rfkill_schedule_evsw_rfkillall(test_bit(SW_RFKILL_ALL, + handle->dev->sw)); + + spin_unlock_irq(&handle->dev->event_lock); +} + +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_MASK(EV_KEY) }, + .keybit = { [BIT_WORD(KEY_WLAN)] = BIT_MASK(KEY_WLAN) }, + }, + { + .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, + .evbit = { BIT_MASK(EV_KEY) }, + .keybit = { [BIT_WORD(KEY_BLUETOOTH)] = BIT_MASK(KEY_BLUETOOTH) }, + }, + { + .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, + .evbit = { BIT_MASK(EV_KEY) }, + .keybit = { [BIT_WORD(KEY_UWB)] = BIT_MASK(KEY_UWB) }, + }, + { + .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, + .evbit = { BIT_MASK(EV_KEY) }, + .keybit = { [BIT_WORD(KEY_WIMAX)] = BIT_MASK(KEY_WIMAX) }, + }, + { + .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_SWBIT, + .evbit = { BIT(EV_SW) }, + .swbit = { [BIT_WORD(SW_RFKILL_ALL)] = BIT_MASK(SW_RFKILL_ALL) }, + }, + { } +}; + +static struct input_handler rfkill_handler = { + .name = "rfkill", + .event = rfkill_event, + .connect = rfkill_connect, + .start = rfkill_start, + .disconnect = rfkill_disconnect, + .id_table = rfkill_ids, +}; + +int __init rfkill_handler_init(void) +{ + switch (rfkill_master_switch_mode) { + case RFKILL_INPUT_MASTER_UNBLOCKALL: + rfkill_master_switch_op = RFKILL_GLOBAL_OP_UNBLOCK; + break; + case RFKILL_INPUT_MASTER_RESTORE: + rfkill_master_switch_op = RFKILL_GLOBAL_OP_RESTORE; + break; + case RFKILL_INPUT_MASTER_UNLOCK: + rfkill_master_switch_op = RFKILL_GLOBAL_OP_UNLOCK; + break; + default: + return -EINVAL; + } + + spin_lock_init(&rfkill_op_lock); + + /* Avoid delay at first schedule */ + rfkill_last_scheduled = + jiffies - msecs_to_jiffies(RFKILL_OPS_DELAY) - 1; + return input_register_handler(&rfkill_handler); +} + +void __exit rfkill_handler_exit(void) +{ + input_unregister_handler(&rfkill_handler); + cancel_delayed_work_sync(&rfkill_op_work); +} |