1 /* ir-raw.c - handle IR pulse/space events
3 * Copyright (C) 2010 by Mauro Carvalho Chehab <mchehab@redhat.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation version 2 of the License.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
15 #include <linux/kthread.h>
16 #include <linux/mutex.h>
17 #include <linux/kmod.h>
18 #include <linux/sched.h>
19 #include <linux/freezer.h>
20 #include "rc-core-priv.h"
22 /* Define the max number of pulse/space transitions to buffer */
23 #define MAX_IR_EVENT_SIZE 512
25 /* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */
26 static LIST_HEAD(ir_raw_client_list);
28 /* Used to handle IR raw handler extensions */
29 static DEFINE_MUTEX(ir_raw_handler_lock);
30 static LIST_HEAD(ir_raw_handler_list);
31 static u64 available_protocols;
34 /* Used to load the decoders */
35 static struct work_struct wq_load;
38 static int ir_raw_event_thread(void *data)
40 struct ir_raw_event ev;
41 struct ir_raw_handler *handler;
42 struct ir_raw_event_ctrl *raw = (struct ir_raw_event_ctrl *)data;
45 while (!kthread_should_stop()) {
47 spin_lock_irq(&raw->lock);
48 retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev));
51 set_current_state(TASK_INTERRUPTIBLE);
53 if (kthread_should_stop())
54 set_current_state(TASK_RUNNING);
56 spin_unlock_irq(&raw->lock);
61 spin_unlock_irq(&raw->lock);
64 BUG_ON(retval != sizeof(ev));
66 mutex_lock(&ir_raw_handler_lock);
67 list_for_each_entry(handler, &ir_raw_handler_list, list)
68 handler->decode(raw->dev, ev);
70 mutex_unlock(&ir_raw_handler_lock);
77 * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
78 * @dev: the struct rc_dev device descriptor
79 * @ev: the struct ir_raw_event descriptor of the pulse/space
81 * This routine (which may be called from an interrupt context) stores a
82 * pulse/space duration for the raw ir decoding state machines. Pulses are
83 * signalled as positive values and spaces as negative values. A zero value
84 * will reset the decoding state machines.
86 int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev)
91 IR_dprintk(2, "sample: (%05dus %s)\n",
92 TO_US(ev->duration), TO_STR(ev->pulse));
94 if (kfifo_in(&dev->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev))
99 EXPORT_SYMBOL_GPL(ir_raw_event_store);
102 * ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space
103 * @dev: the struct rc_dev device descriptor
104 * @type: the type of the event that has occurred
106 * This routine (which may be called from an interrupt context) is used to
107 * store the beginning of an ir pulse or space (or the start/end of ir
108 * reception) for the raw ir decoding state machines. This is used by
109 * hardware which does not provide durations directly but only interrupts
110 * (or similar events) on state change.
112 int ir_raw_event_store_edge(struct rc_dev *dev, enum raw_event_type type)
116 DEFINE_IR_RAW_EVENT(ev);
124 delta = ktime_to_ns(ktime_sub(now, dev->raw->last_event));
125 delay = MS_TO_NS(dev->input_dev->rep[REP_DELAY]);
127 /* Check for a long duration since last event or if we're
128 * being called for the first time, note that delta can't
129 * possibly be negative.
131 if (delta > delay || !dev->raw->last_type)
132 type |= IR_START_EVENT;
136 if (type & IR_START_EVENT)
137 ir_raw_event_reset(dev);
138 else if (dev->raw->last_type & IR_SPACE) {
140 rc = ir_raw_event_store(dev, &ev);
141 } else if (dev->raw->last_type & IR_PULSE) {
143 rc = ir_raw_event_store(dev, &ev);
147 dev->raw->last_event = now;
148 dev->raw->last_type = type;
151 EXPORT_SYMBOL_GPL(ir_raw_event_store_edge);
154 * ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing
155 * @dev: the struct rc_dev device descriptor
156 * @type: the type of the event that has occurred
158 * This routine (which may be called from an interrupt context) works
159 * in similar manner to ir_raw_event_store_edge.
160 * This routine is intended for devices with limited internal buffer
161 * It automerges samples of same type, and handles timeouts
163 int ir_raw_event_store_with_filter(struct rc_dev *dev, struct ir_raw_event *ev)
168 /* Ignore spaces in idle mode */
169 if (dev->idle && !ev->pulse)
172 ir_raw_event_set_idle(dev, false);
174 if (!dev->raw->this_ev.duration)
175 dev->raw->this_ev = *ev;
176 else if (ev->pulse == dev->raw->this_ev.pulse)
177 dev->raw->this_ev.duration += ev->duration;
179 ir_raw_event_store(dev, &dev->raw->this_ev);
180 dev->raw->this_ev = *ev;
183 /* Enter idle mode if nessesary */
184 if (!ev->pulse && dev->timeout &&
185 dev->raw->this_ev.duration >= dev->timeout)
186 ir_raw_event_set_idle(dev, true);
190 EXPORT_SYMBOL_GPL(ir_raw_event_store_with_filter);
193 * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not
194 * @dev: the struct rc_dev device descriptor
195 * @idle: whether the device is idle or not
197 void ir_raw_event_set_idle(struct rc_dev *dev, bool idle)
202 IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave");
205 dev->raw->this_ev.timeout = true;
206 ir_raw_event_store(dev, &dev->raw->this_ev);
207 init_ir_raw_event(&dev->raw->this_ev);
211 dev->s_idle(dev, idle);
215 EXPORT_SYMBOL_GPL(ir_raw_event_set_idle);
218 * ir_raw_event_handle() - schedules the decoding of stored ir data
219 * @dev: the struct rc_dev device descriptor
221 * This routine will tell rc-core to start decoding stored ir data.
223 void ir_raw_event_handle(struct rc_dev *dev)
230 spin_lock_irqsave(&dev->raw->lock, flags);
231 wake_up_process(dev->raw->thread);
232 spin_unlock_irqrestore(&dev->raw->lock, flags);
234 EXPORT_SYMBOL_GPL(ir_raw_event_handle);
236 /* used internally by the sysfs interface */
238 ir_raw_get_allowed_protocols(void)
241 mutex_lock(&ir_raw_handler_lock);
242 protocols = available_protocols;
243 mutex_unlock(&ir_raw_handler_lock);
248 * Used to (un)register raw event clients
250 int ir_raw_event_register(struct rc_dev *dev)
253 struct ir_raw_handler *handler;
258 dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL);
263 dev->raw->enabled_protocols = ~0;
264 rc = kfifo_alloc(&dev->raw->kfifo,
265 sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE,
270 spin_lock_init(&dev->raw->lock);
271 dev->raw->thread = kthread_run(ir_raw_event_thread, dev->raw,
272 "rc%ld", dev->devno);
274 if (IS_ERR(dev->raw->thread)) {
275 rc = PTR_ERR(dev->raw->thread);
279 mutex_lock(&ir_raw_handler_lock);
280 list_add_tail(&dev->raw->list, &ir_raw_client_list);
281 list_for_each_entry(handler, &ir_raw_handler_list, list)
282 if (handler->raw_register)
283 handler->raw_register(dev);
284 mutex_unlock(&ir_raw_handler_lock);
294 void ir_raw_event_unregister(struct rc_dev *dev)
296 struct ir_raw_handler *handler;
298 if (!dev || !dev->raw)
301 kthread_stop(dev->raw->thread);
303 mutex_lock(&ir_raw_handler_lock);
304 list_del(&dev->raw->list);
305 list_for_each_entry(handler, &ir_raw_handler_list, list)
306 if (handler->raw_unregister)
307 handler->raw_unregister(dev);
308 mutex_unlock(&ir_raw_handler_lock);
310 kfifo_free(&dev->raw->kfifo);
316 * Extension interface - used to register the IR decoders
319 int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler)
321 struct ir_raw_event_ctrl *raw;
323 mutex_lock(&ir_raw_handler_lock);
324 list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list);
325 if (ir_raw_handler->raw_register)
326 list_for_each_entry(raw, &ir_raw_client_list, list)
327 ir_raw_handler->raw_register(raw->dev);
328 available_protocols |= ir_raw_handler->protocols;
329 mutex_unlock(&ir_raw_handler_lock);
333 EXPORT_SYMBOL(ir_raw_handler_register);
335 void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler)
337 struct ir_raw_event_ctrl *raw;
339 mutex_lock(&ir_raw_handler_lock);
340 list_del(&ir_raw_handler->list);
341 if (ir_raw_handler->raw_unregister)
342 list_for_each_entry(raw, &ir_raw_client_list, list)
343 ir_raw_handler->raw_unregister(raw->dev);
344 available_protocols &= ~ir_raw_handler->protocols;
345 mutex_unlock(&ir_raw_handler_lock);
347 EXPORT_SYMBOL(ir_raw_handler_unregister);
350 static void init_decoders(struct work_struct *work)
352 /* Load the decoder modules */
359 load_mce_kbd_decode();
362 /* If needed, we may later add some init code. In this case,
363 it is needed to change the CONFIG_MODULE test at rc-core.h
368 void ir_raw_init(void)
371 INIT_WORK(&wq_load, init_decoders);
372 schedule_work(&wq_load);