1 /* ir-raw-event.c - handle IR Pulse/Space event
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/workqueue.h>
16 #include <linux/spinlock.h>
17 #include <linux/sched.h>
18 #include "ir-core-priv.h"
20 /* Define the max number of pulse/space transitions to buffer */
21 #define MAX_IR_EVENT_SIZE 512
23 /* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */
24 static LIST_HEAD(ir_raw_client_list);
26 /* Used to handle IR raw handler extensions */
27 static DEFINE_SPINLOCK(ir_raw_handler_lock);
28 static LIST_HEAD(ir_raw_handler_list);
29 static u64 available_protocols;
32 /* Used to load the decoders */
33 static struct work_struct wq_load;
36 static void ir_raw_event_work(struct work_struct *work)
38 struct ir_raw_event ev;
39 struct ir_raw_handler *handler;
40 struct ir_raw_event_ctrl *raw =
41 container_of(work, struct ir_raw_event_ctrl, rx_work);
43 while (kfifo_out(&raw->kfifo, &ev, sizeof(ev)) == sizeof(ev)) {
44 spin_lock(&ir_raw_handler_lock);
45 list_for_each_entry(handler, &ir_raw_handler_list, list)
46 handler->decode(raw->input_dev, ev);
47 spin_unlock(&ir_raw_handler_lock);
53 * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
54 * @input_dev: the struct input_dev device descriptor
55 * @ev: the struct ir_raw_event descriptor of the pulse/space
57 * This routine (which may be called from an interrupt context) stores a
58 * pulse/space duration for the raw ir decoding state machines. Pulses are
59 * signalled as positive values and spaces as negative values. A zero value
60 * will reset the decoding state machines.
62 int ir_raw_event_store(struct input_dev *input_dev, struct ir_raw_event *ev)
64 struct ir_input_dev *ir = input_get_drvdata(input_dev);
69 if (kfifo_in(&ir->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev))
74 EXPORT_SYMBOL_GPL(ir_raw_event_store);
77 * ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space
78 * @input_dev: the struct input_dev device descriptor
79 * @type: the type of the event that has occurred
81 * This routine (which may be called from an interrupt context) is used to
82 * store the beginning of an ir pulse or space (or the start/end of ir
83 * reception) for the raw ir decoding state machines. This is used by
84 * hardware which does not provide durations directly but only interrupts
85 * (or similar events) on state change.
87 int ir_raw_event_store_edge(struct input_dev *input_dev, enum raw_event_type type)
89 struct ir_input_dev *ir = input_get_drvdata(input_dev);
92 struct ir_raw_event ev;
99 delta = ktime_to_ns(ktime_sub(now, ir->raw->last_event));
101 /* Check for a long duration since last event or if we're
102 * being called for the first time, note that delta can't
103 * possibly be negative.
106 if (delta > IR_MAX_DURATION || !ir->raw->last_type)
107 type |= IR_START_EVENT;
111 if (type & IR_START_EVENT)
112 ir_raw_event_reset(input_dev);
113 else if (ir->raw->last_type & IR_SPACE) {
115 rc = ir_raw_event_store(input_dev, &ev);
116 } else if (ir->raw->last_type & IR_PULSE) {
118 rc = ir_raw_event_store(input_dev, &ev);
122 ir->raw->last_event = now;
123 ir->raw->last_type = type;
126 EXPORT_SYMBOL_GPL(ir_raw_event_store_edge);
129 * ir_raw_event_handle() - schedules the decoding of stored ir data
130 * @input_dev: the struct input_dev device descriptor
132 * This routine will signal the workqueue to start decoding stored ir data.
134 void ir_raw_event_handle(struct input_dev *input_dev)
136 struct ir_input_dev *ir = input_get_drvdata(input_dev);
141 schedule_work(&ir->raw->rx_work);
143 EXPORT_SYMBOL_GPL(ir_raw_event_handle);
145 /* used internally by the sysfs interface */
147 ir_raw_get_allowed_protocols()
150 spin_lock(&ir_raw_handler_lock);
151 protocols = available_protocols;
152 spin_unlock(&ir_raw_handler_lock);
157 * Used to (un)register raw event clients
159 int ir_raw_event_register(struct input_dev *input_dev)
161 struct ir_input_dev *ir = input_get_drvdata(input_dev);
163 struct ir_raw_handler *handler;
165 ir->raw = kzalloc(sizeof(*ir->raw), GFP_KERNEL);
169 ir->raw->input_dev = input_dev;
170 INIT_WORK(&ir->raw->rx_work, ir_raw_event_work);
171 ir->raw->enabled_protocols = ~0;
172 rc = kfifo_alloc(&ir->raw->kfifo, sizeof(s64) * MAX_IR_EVENT_SIZE,
180 spin_lock(&ir_raw_handler_lock);
181 list_add_tail(&ir->raw->list, &ir_raw_client_list);
182 list_for_each_entry(handler, &ir_raw_handler_list, list)
183 if (handler->raw_register)
184 handler->raw_register(ir->raw->input_dev);
185 spin_unlock(&ir_raw_handler_lock);
190 void ir_raw_event_unregister(struct input_dev *input_dev)
192 struct ir_input_dev *ir = input_get_drvdata(input_dev);
193 struct ir_raw_handler *handler;
198 cancel_work_sync(&ir->raw->rx_work);
200 spin_lock(&ir_raw_handler_lock);
201 list_del(&ir->raw->list);
202 list_for_each_entry(handler, &ir_raw_handler_list, list)
203 if (handler->raw_unregister)
204 handler->raw_unregister(ir->raw->input_dev);
205 spin_unlock(&ir_raw_handler_lock);
207 kfifo_free(&ir->raw->kfifo);
213 * Extension interface - used to register the IR decoders
216 int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler)
218 struct ir_raw_event_ctrl *raw;
220 spin_lock(&ir_raw_handler_lock);
221 list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list);
222 if (ir_raw_handler->raw_register)
223 list_for_each_entry(raw, &ir_raw_client_list, list)
224 ir_raw_handler->raw_register(raw->input_dev);
225 available_protocols |= ir_raw_handler->protocols;
226 spin_unlock(&ir_raw_handler_lock);
230 EXPORT_SYMBOL(ir_raw_handler_register);
232 void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler)
234 struct ir_raw_event_ctrl *raw;
236 spin_lock(&ir_raw_handler_lock);
237 list_del(&ir_raw_handler->list);
238 if (ir_raw_handler->raw_unregister)
239 list_for_each_entry(raw, &ir_raw_client_list, list)
240 ir_raw_handler->raw_unregister(raw->input_dev);
241 available_protocols &= ~ir_raw_handler->protocols;
242 spin_unlock(&ir_raw_handler_lock);
244 EXPORT_SYMBOL(ir_raw_handler_unregister);
247 static void init_decoders(struct work_struct *work)
249 /* Load the decoder modules */
258 /* If needed, we may later add some init code. In this case,
259 it is needed to change the CONFIG_MODULE test at ir-core.h
264 void ir_raw_init(void)
267 INIT_WORK(&wq_load, init_decoders);
268 schedule_work(&wq_load);