| 1 | /* rc-ir-raw.c - handle IR pulse/space events |
| 2 | * |
| 3 | * Copyright (C) 2010 by Mauro Carvalho Chehab |
| 4 | * |
| 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. |
| 8 | * |
| 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. |
| 13 | */ |
| 14 | |
| 15 | #include <linux/export.h> |
| 16 | #include <linux/kthread.h> |
| 17 | #include <linux/mutex.h> |
| 18 | #include <linux/kmod.h> |
| 19 | #include <linux/sched.h> |
| 20 | #include <linux/freezer.h> |
| 21 | #include "rc-core-priv.h" |
| 22 | |
| 23 | /* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */ |
| 24 | static LIST_HEAD(ir_raw_client_list); |
| 25 | |
| 26 | /* Used to handle IR raw handler extensions */ |
| 27 | static DEFINE_MUTEX(ir_raw_handler_lock); |
| 28 | static LIST_HEAD(ir_raw_handler_list); |
| 29 | static u64 available_protocols; |
| 30 | |
| 31 | static int ir_raw_event_thread(void *data) |
| 32 | { |
| 33 | struct ir_raw_event ev; |
| 34 | struct ir_raw_handler *handler; |
| 35 | struct ir_raw_event_ctrl *raw = (struct ir_raw_event_ctrl *)data; |
| 36 | |
| 37 | while (!kthread_should_stop()) { |
| 38 | |
| 39 | spin_lock_irq(&raw->lock); |
| 40 | |
| 41 | if (!kfifo_len(&raw->kfifo)) { |
| 42 | set_current_state(TASK_INTERRUPTIBLE); |
| 43 | |
| 44 | if (kthread_should_stop()) |
| 45 | set_current_state(TASK_RUNNING); |
| 46 | |
| 47 | spin_unlock_irq(&raw->lock); |
| 48 | schedule(); |
| 49 | continue; |
| 50 | } |
| 51 | |
| 52 | if(!kfifo_out(&raw->kfifo, &ev, 1)) |
| 53 | dev_err(&raw->dev->dev, "IR event FIFO is empty!\n"); |
| 54 | spin_unlock_irq(&raw->lock); |
| 55 | |
| 56 | mutex_lock(&ir_raw_handler_lock); |
| 57 | list_for_each_entry(handler, &ir_raw_handler_list, list) |
| 58 | if (raw->dev->enabled_protocols & handler->protocols || |
| 59 | !handler->protocols) |
| 60 | handler->decode(raw->dev, ev); |
| 61 | raw->prev_ev = ev; |
| 62 | mutex_unlock(&ir_raw_handler_lock); |
| 63 | } |
| 64 | |
| 65 | return 0; |
| 66 | } |
| 67 | |
| 68 | /** |
| 69 | * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders |
| 70 | * @dev: the struct rc_dev device descriptor |
| 71 | * @ev: the struct ir_raw_event descriptor of the pulse/space |
| 72 | * |
| 73 | * This routine (which may be called from an interrupt context) stores a |
| 74 | * pulse/space duration for the raw ir decoding state machines. Pulses are |
| 75 | * signalled as positive values and spaces as negative values. A zero value |
| 76 | * will reset the decoding state machines. |
| 77 | */ |
| 78 | int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev) |
| 79 | { |
| 80 | if (!dev->raw) |
| 81 | return -EINVAL; |
| 82 | |
| 83 | IR_dprintk(2, "sample: (%05dus %s)\n", |
| 84 | TO_US(ev->duration), TO_STR(ev->pulse)); |
| 85 | |
| 86 | if (!kfifo_put(&dev->raw->kfifo, *ev)) { |
| 87 | dev_err(&dev->dev, "IR event FIFO is full!\n"); |
| 88 | return -ENOSPC; |
| 89 | } |
| 90 | |
| 91 | return 0; |
| 92 | } |
| 93 | EXPORT_SYMBOL_GPL(ir_raw_event_store); |
| 94 | |
| 95 | /** |
| 96 | * ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space |
| 97 | * @dev: the struct rc_dev device descriptor |
| 98 | * @type: the type of the event that has occurred |
| 99 | * |
| 100 | * This routine (which may be called from an interrupt context) is used to |
| 101 | * store the beginning of an ir pulse or space (or the start/end of ir |
| 102 | * reception) for the raw ir decoding state machines. This is used by |
| 103 | * hardware which does not provide durations directly but only interrupts |
| 104 | * (or similar events) on state change. |
| 105 | */ |
| 106 | int ir_raw_event_store_edge(struct rc_dev *dev, enum raw_event_type type) |
| 107 | { |
| 108 | ktime_t now; |
| 109 | s64 delta; /* ns */ |
| 110 | DEFINE_IR_RAW_EVENT(ev); |
| 111 | int rc = 0; |
| 112 | int delay; |
| 113 | |
| 114 | if (!dev->raw) |
| 115 | return -EINVAL; |
| 116 | |
| 117 | now = ktime_get(); |
| 118 | delta = ktime_to_ns(ktime_sub(now, dev->raw->last_event)); |
| 119 | delay = MS_TO_NS(dev->input_dev->rep[REP_DELAY]); |
| 120 | |
| 121 | /* Check for a long duration since last event or if we're |
| 122 | * being called for the first time, note that delta can't |
| 123 | * possibly be negative. |
| 124 | */ |
| 125 | if (delta > delay || !dev->raw->last_type) |
| 126 | type |= IR_START_EVENT; |
| 127 | else |
| 128 | ev.duration = delta; |
| 129 | |
| 130 | if (type & IR_START_EVENT) |
| 131 | ir_raw_event_reset(dev); |
| 132 | else if (dev->raw->last_type & IR_SPACE) { |
| 133 | ev.pulse = false; |
| 134 | rc = ir_raw_event_store(dev, &ev); |
| 135 | } else if (dev->raw->last_type & IR_PULSE) { |
| 136 | ev.pulse = true; |
| 137 | rc = ir_raw_event_store(dev, &ev); |
| 138 | } else |
| 139 | return 0; |
| 140 | |
| 141 | dev->raw->last_event = now; |
| 142 | dev->raw->last_type = type; |
| 143 | return rc; |
| 144 | } |
| 145 | EXPORT_SYMBOL_GPL(ir_raw_event_store_edge); |
| 146 | |
| 147 | /** |
| 148 | * ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing |
| 149 | * @dev: the struct rc_dev device descriptor |
| 150 | * @type: the type of the event that has occurred |
| 151 | * |
| 152 | * This routine (which may be called from an interrupt context) works |
| 153 | * in similar manner to ir_raw_event_store_edge. |
| 154 | * This routine is intended for devices with limited internal buffer |
| 155 | * It automerges samples of same type, and handles timeouts. Returns non-zero |
| 156 | * if the event was added, and zero if the event was ignored due to idle |
| 157 | * processing. |
| 158 | */ |
| 159 | int ir_raw_event_store_with_filter(struct rc_dev *dev, struct ir_raw_event *ev) |
| 160 | { |
| 161 | if (!dev->raw) |
| 162 | return -EINVAL; |
| 163 | |
| 164 | /* Ignore spaces in idle mode */ |
| 165 | if (dev->idle && !ev->pulse) |
| 166 | return 0; |
| 167 | else if (dev->idle) |
| 168 | ir_raw_event_set_idle(dev, false); |
| 169 | |
| 170 | if (!dev->raw->this_ev.duration) |
| 171 | dev->raw->this_ev = *ev; |
| 172 | else if (ev->pulse == dev->raw->this_ev.pulse) |
| 173 | dev->raw->this_ev.duration += ev->duration; |
| 174 | else { |
| 175 | ir_raw_event_store(dev, &dev->raw->this_ev); |
| 176 | dev->raw->this_ev = *ev; |
| 177 | } |
| 178 | |
| 179 | /* Enter idle mode if nessesary */ |
| 180 | if (!ev->pulse && dev->timeout && |
| 181 | dev->raw->this_ev.duration >= dev->timeout) |
| 182 | ir_raw_event_set_idle(dev, true); |
| 183 | |
| 184 | return 1; |
| 185 | } |
| 186 | EXPORT_SYMBOL_GPL(ir_raw_event_store_with_filter); |
| 187 | |
| 188 | /** |
| 189 | * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not |
| 190 | * @dev: the struct rc_dev device descriptor |
| 191 | * @idle: whether the device is idle or not |
| 192 | */ |
| 193 | void ir_raw_event_set_idle(struct rc_dev *dev, bool idle) |
| 194 | { |
| 195 | if (!dev->raw) |
| 196 | return; |
| 197 | |
| 198 | IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave"); |
| 199 | |
| 200 | if (idle) { |
| 201 | dev->raw->this_ev.timeout = true; |
| 202 | ir_raw_event_store(dev, &dev->raw->this_ev); |
| 203 | init_ir_raw_event(&dev->raw->this_ev); |
| 204 | } |
| 205 | |
| 206 | if (dev->s_idle) |
| 207 | dev->s_idle(dev, idle); |
| 208 | |
| 209 | dev->idle = idle; |
| 210 | } |
| 211 | EXPORT_SYMBOL_GPL(ir_raw_event_set_idle); |
| 212 | |
| 213 | /** |
| 214 | * ir_raw_event_handle() - schedules the decoding of stored ir data |
| 215 | * @dev: the struct rc_dev device descriptor |
| 216 | * |
| 217 | * This routine will tell rc-core to start decoding stored ir data. |
| 218 | */ |
| 219 | void ir_raw_event_handle(struct rc_dev *dev) |
| 220 | { |
| 221 | unsigned long flags; |
| 222 | |
| 223 | if (!dev->raw) |
| 224 | return; |
| 225 | |
| 226 | spin_lock_irqsave(&dev->raw->lock, flags); |
| 227 | wake_up_process(dev->raw->thread); |
| 228 | spin_unlock_irqrestore(&dev->raw->lock, flags); |
| 229 | } |
| 230 | EXPORT_SYMBOL_GPL(ir_raw_event_handle); |
| 231 | |
| 232 | /* used internally by the sysfs interface */ |
| 233 | u64 |
| 234 | ir_raw_get_allowed_protocols(void) |
| 235 | { |
| 236 | u64 protocols; |
| 237 | mutex_lock(&ir_raw_handler_lock); |
| 238 | protocols = available_protocols; |
| 239 | mutex_unlock(&ir_raw_handler_lock); |
| 240 | return protocols; |
| 241 | } |
| 242 | |
| 243 | static int change_protocol(struct rc_dev *dev, u64 *rc_type) |
| 244 | { |
| 245 | /* the caller will update dev->enabled_protocols */ |
| 246 | return 0; |
| 247 | } |
| 248 | |
| 249 | static void ir_raw_disable_protocols(struct rc_dev *dev, u64 protocols) |
| 250 | { |
| 251 | mutex_lock(&dev->lock); |
| 252 | dev->enabled_protocols &= ~protocols; |
| 253 | dev->enabled_wakeup_protocols &= ~protocols; |
| 254 | mutex_unlock(&dev->lock); |
| 255 | } |
| 256 | |
| 257 | /* |
| 258 | * Used to (un)register raw event clients |
| 259 | */ |
| 260 | int ir_raw_event_register(struct rc_dev *dev) |
| 261 | { |
| 262 | int rc; |
| 263 | struct ir_raw_handler *handler; |
| 264 | |
| 265 | if (!dev) |
| 266 | return -EINVAL; |
| 267 | |
| 268 | dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL); |
| 269 | if (!dev->raw) |
| 270 | return -ENOMEM; |
| 271 | |
| 272 | dev->raw->dev = dev; |
| 273 | dev->change_protocol = change_protocol; |
| 274 | INIT_KFIFO(dev->raw->kfifo); |
| 275 | |
| 276 | spin_lock_init(&dev->raw->lock); |
| 277 | dev->raw->thread = kthread_run(ir_raw_event_thread, dev->raw, |
| 278 | "rc%u", dev->minor); |
| 279 | |
| 280 | if (IS_ERR(dev->raw->thread)) { |
| 281 | rc = PTR_ERR(dev->raw->thread); |
| 282 | goto out; |
| 283 | } |
| 284 | |
| 285 | mutex_lock(&ir_raw_handler_lock); |
| 286 | list_add_tail(&dev->raw->list, &ir_raw_client_list); |
| 287 | list_for_each_entry(handler, &ir_raw_handler_list, list) |
| 288 | if (handler->raw_register) |
| 289 | handler->raw_register(dev); |
| 290 | mutex_unlock(&ir_raw_handler_lock); |
| 291 | |
| 292 | return 0; |
| 293 | |
| 294 | out: |
| 295 | kfree(dev->raw); |
| 296 | dev->raw = NULL; |
| 297 | return rc; |
| 298 | } |
| 299 | |
| 300 | void ir_raw_event_unregister(struct rc_dev *dev) |
| 301 | { |
| 302 | struct ir_raw_handler *handler; |
| 303 | |
| 304 | if (!dev || !dev->raw) |
| 305 | return; |
| 306 | |
| 307 | kthread_stop(dev->raw->thread); |
| 308 | |
| 309 | mutex_lock(&ir_raw_handler_lock); |
| 310 | list_del(&dev->raw->list); |
| 311 | list_for_each_entry(handler, &ir_raw_handler_list, list) |
| 312 | if (handler->raw_unregister) |
| 313 | handler->raw_unregister(dev); |
| 314 | mutex_unlock(&ir_raw_handler_lock); |
| 315 | |
| 316 | kfree(dev->raw); |
| 317 | dev->raw = NULL; |
| 318 | } |
| 319 | |
| 320 | /* |
| 321 | * Extension interface - used to register the IR decoders |
| 322 | */ |
| 323 | |
| 324 | int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler) |
| 325 | { |
| 326 | struct ir_raw_event_ctrl *raw; |
| 327 | |
| 328 | mutex_lock(&ir_raw_handler_lock); |
| 329 | list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list); |
| 330 | if (ir_raw_handler->raw_register) |
| 331 | list_for_each_entry(raw, &ir_raw_client_list, list) |
| 332 | ir_raw_handler->raw_register(raw->dev); |
| 333 | available_protocols |= ir_raw_handler->protocols; |
| 334 | mutex_unlock(&ir_raw_handler_lock); |
| 335 | |
| 336 | return 0; |
| 337 | } |
| 338 | EXPORT_SYMBOL(ir_raw_handler_register); |
| 339 | |
| 340 | void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler) |
| 341 | { |
| 342 | struct ir_raw_event_ctrl *raw; |
| 343 | u64 protocols = ir_raw_handler->protocols; |
| 344 | |
| 345 | mutex_lock(&ir_raw_handler_lock); |
| 346 | list_del(&ir_raw_handler->list); |
| 347 | list_for_each_entry(raw, &ir_raw_client_list, list) { |
| 348 | ir_raw_disable_protocols(raw->dev, protocols); |
| 349 | if (ir_raw_handler->raw_unregister) |
| 350 | ir_raw_handler->raw_unregister(raw->dev); |
| 351 | } |
| 352 | available_protocols &= ~protocols; |
| 353 | mutex_unlock(&ir_raw_handler_lock); |
| 354 | } |
| 355 | EXPORT_SYMBOL(ir_raw_handler_unregister); |