1 /* ir-lirc-codec.c - rc-core to classic lirc interface bridge
2 *
3 * Copyright (C) 2010 by Jarod Wilson <jarod@redhat.com>
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/sched.h>
16 #include <linux/wait.h>
17 #include <linux/module.h>
18 #include <media/lirc.h>
19 #include <media/lirc_dev.h>
20 #include <media/rc-core.h>
21 #include "rc-core-priv.h"
22
23 #define LIRCBUF_SIZE 256
24
25 /**
26 * ir_lirc_decode() - Send raw IR data to lirc_dev to be relayed to the
27 * lircd userspace daemon for decoding.
28 * @input_dev: the struct rc_dev descriptor of the device
29 * @duration: the struct ir_raw_event descriptor of the pulse/space
30 *
31 * This function returns -EINVAL if the lirc interfaces aren't wired up.
32 */
ir_lirc_decode(struct rc_dev * dev,struct ir_raw_event ev)33 static int ir_lirc_decode(struct rc_dev *dev, struct ir_raw_event ev)
34 {
35 struct lirc_codec *lirc = &dev->raw->lirc;
36 int sample;
37
38 if (!(dev->enabled_protocols & RC_BIT_LIRC))
39 return 0;
40
41 if (!dev->raw->lirc.drv || !dev->raw->lirc.drv->rbuf)
42 return -EINVAL;
43
44 /* Packet start */
45 if (ev.reset)
46 return 0;
47
48 /* Carrier reports */
49 if (ev.carrier_report) {
50 sample = LIRC_FREQUENCY(ev.carrier);
51 IR_dprintk(2, "carrier report (freq: %d)\n", sample);
52
53 /* Packet end */
54 } else if (ev.timeout) {
55
56 if (lirc->gap)
57 return 0;
58
59 lirc->gap_start = ktime_get();
60 lirc->gap = true;
61 lirc->gap_duration = ev.duration;
62
63 if (!lirc->send_timeout_reports)
64 return 0;
65
66 sample = LIRC_TIMEOUT(ev.duration / 1000);
67 IR_dprintk(2, "timeout report (duration: %d)\n", sample);
68
69 /* Normal sample */
70 } else {
71
72 if (lirc->gap) {
73 int gap_sample;
74
75 lirc->gap_duration += ktime_to_ns(ktime_sub(ktime_get(),
76 lirc->gap_start));
77
78 /* Convert to ms and cap by LIRC_VALUE_MASK */
79 do_div(lirc->gap_duration, 1000);
80 lirc->gap_duration = min(lirc->gap_duration,
81 (u64)LIRC_VALUE_MASK);
82
83 gap_sample = LIRC_SPACE(lirc->gap_duration);
84 lirc_buffer_write(dev->raw->lirc.drv->rbuf,
85 (unsigned char *) &gap_sample);
86 lirc->gap = false;
87 }
88
89 sample = ev.pulse ? LIRC_PULSE(ev.duration / 1000) :
90 LIRC_SPACE(ev.duration / 1000);
91 IR_dprintk(2, "delivering %uus %s to lirc_dev\n",
92 TO_US(ev.duration), TO_STR(ev.pulse));
93 }
94
95 lirc_buffer_write(dev->raw->lirc.drv->rbuf,
96 (unsigned char *) &sample);
97 wake_up(&dev->raw->lirc.drv->rbuf->wait_poll);
98
99 return 0;
100 }
101
ir_lirc_transmit_ir(struct file * file,const char __user * buf,size_t n,loff_t * ppos)102 static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
103 size_t n, loff_t *ppos)
104 {
105 struct lirc_codec *lirc;
106 struct rc_dev *dev;
107 unsigned int *txbuf; /* buffer with values to transmit */
108 ssize_t ret = -EINVAL;
109 size_t count;
110 ktime_t start;
111 s64 towait;
112 unsigned int duration = 0; /* signal duration in us */
113 int i;
114
115 start = ktime_get();
116
117 lirc = lirc_get_pdata(file);
118 if (!lirc)
119 return -EFAULT;
120
121 if (n < sizeof(unsigned) || n % sizeof(unsigned))
122 return -EINVAL;
123
124 count = n / sizeof(unsigned);
125 if (count > LIRCBUF_SIZE || count % 2 == 0)
126 return -EINVAL;
127
128 txbuf = memdup_user(buf, n);
129 if (IS_ERR(txbuf))
130 return PTR_ERR(txbuf);
131
132 dev = lirc->dev;
133 if (!dev) {
134 ret = -EFAULT;
135 goto out;
136 }
137
138 if (!dev->tx_ir) {
139 ret = -ENOSYS;
140 goto out;
141 }
142
143 ret = dev->tx_ir(dev, txbuf, count);
144 if (ret < 0)
145 goto out;
146
147 for (i = 0; i < ret; i++)
148 duration += txbuf[i];
149
150 ret *= sizeof(unsigned int);
151
152 /*
153 * The lircd gap calculation expects the write function to
154 * wait for the actual IR signal to be transmitted before
155 * returning.
156 */
157 towait = ktime_us_delta(ktime_add_us(start, duration), ktime_get());
158 if (towait > 0) {
159 set_current_state(TASK_INTERRUPTIBLE);
160 schedule_timeout(usecs_to_jiffies(towait));
161 }
162
163 out:
164 kfree(txbuf);
165 return ret;
166 }
167
ir_lirc_ioctl(struct file * filep,unsigned int cmd,unsigned long arg)168 static long ir_lirc_ioctl(struct file *filep, unsigned int cmd,
169 unsigned long arg)
170 {
171 struct lirc_codec *lirc;
172 struct rc_dev *dev;
173 u32 __user *argp = (u32 __user *)(arg);
174 int ret = 0;
175 __u32 val = 0, tmp;
176
177 lirc = lirc_get_pdata(filep);
178 if (!lirc)
179 return -EFAULT;
180
181 dev = lirc->dev;
182 if (!dev)
183 return -EFAULT;
184
185 if (_IOC_DIR(cmd) & _IOC_WRITE) {
186 ret = get_user(val, argp);
187 if (ret)
188 return ret;
189 }
190
191 switch (cmd) {
192
193 /* legacy support */
194 case LIRC_GET_SEND_MODE:
195 val = LIRC_CAN_SEND_PULSE & LIRC_CAN_SEND_MASK;
196 break;
197
198 case LIRC_SET_SEND_MODE:
199 if (val != (LIRC_MODE_PULSE & LIRC_CAN_SEND_MASK))
200 return -EINVAL;
201 return 0;
202
203 /* TX settings */
204 case LIRC_SET_TRANSMITTER_MASK:
205 if (!dev->s_tx_mask)
206 return -ENOSYS;
207
208 return dev->s_tx_mask(dev, val);
209
210 case LIRC_SET_SEND_CARRIER:
211 if (!dev->s_tx_carrier)
212 return -ENOSYS;
213
214 return dev->s_tx_carrier(dev, val);
215
216 case LIRC_SET_SEND_DUTY_CYCLE:
217 if (!dev->s_tx_duty_cycle)
218 return -ENOSYS;
219
220 if (val <= 0 || val >= 100)
221 return -EINVAL;
222
223 return dev->s_tx_duty_cycle(dev, val);
224
225 /* RX settings */
226 case LIRC_SET_REC_CARRIER:
227 if (!dev->s_rx_carrier_range)
228 return -ENOSYS;
229
230 if (val <= 0)
231 return -EINVAL;
232
233 return dev->s_rx_carrier_range(dev,
234 dev->raw->lirc.carrier_low,
235 val);
236
237 case LIRC_SET_REC_CARRIER_RANGE:
238 if (val <= 0)
239 return -EINVAL;
240
241 dev->raw->lirc.carrier_low = val;
242 return 0;
243
244 case LIRC_GET_REC_RESOLUTION:
245 val = dev->rx_resolution;
246 break;
247
248 case LIRC_SET_WIDEBAND_RECEIVER:
249 if (!dev->s_learning_mode)
250 return -ENOSYS;
251
252 return dev->s_learning_mode(dev, !!val);
253
254 case LIRC_SET_MEASURE_CARRIER_MODE:
255 if (!dev->s_carrier_report)
256 return -ENOSYS;
257
258 return dev->s_carrier_report(dev, !!val);
259
260 /* Generic timeout support */
261 case LIRC_GET_MIN_TIMEOUT:
262 if (!dev->max_timeout)
263 return -ENOSYS;
264 val = dev->min_timeout / 1000;
265 break;
266
267 case LIRC_GET_MAX_TIMEOUT:
268 if (!dev->max_timeout)
269 return -ENOSYS;
270 val = dev->max_timeout / 1000;
271 break;
272
273 case LIRC_SET_REC_TIMEOUT:
274 if (!dev->max_timeout)
275 return -ENOSYS;
276
277 tmp = val * 1000;
278
279 if (tmp < dev->min_timeout ||
280 tmp > dev->max_timeout)
281 return -EINVAL;
282
283 dev->timeout = tmp;
284 break;
285
286 case LIRC_SET_REC_TIMEOUT_REPORTS:
287 lirc->send_timeout_reports = !!val;
288 break;
289
290 default:
291 return lirc_dev_fop_ioctl(filep, cmd, arg);
292 }
293
294 if (_IOC_DIR(cmd) & _IOC_READ)
295 ret = put_user(val, argp);
296
297 return ret;
298 }
299
ir_lirc_open(void * data)300 static int ir_lirc_open(void *data)
301 {
302 return 0;
303 }
304
ir_lirc_close(void * data)305 static void ir_lirc_close(void *data)
306 {
307 return;
308 }
309
310 static const struct file_operations lirc_fops = {
311 .owner = THIS_MODULE,
312 .write = ir_lirc_transmit_ir,
313 .unlocked_ioctl = ir_lirc_ioctl,
314 #ifdef CONFIG_COMPAT
315 .compat_ioctl = ir_lirc_ioctl,
316 #endif
317 .read = lirc_dev_fop_read,
318 .poll = lirc_dev_fop_poll,
319 .open = lirc_dev_fop_open,
320 .release = lirc_dev_fop_close,
321 .llseek = no_llseek,
322 };
323
ir_lirc_register(struct rc_dev * dev)324 static int ir_lirc_register(struct rc_dev *dev)
325 {
326 struct lirc_driver *drv;
327 struct lirc_buffer *rbuf;
328 int rc = -ENOMEM;
329 unsigned long features;
330
331 drv = kzalloc(sizeof(struct lirc_driver), GFP_KERNEL);
332 if (!drv)
333 return rc;
334
335 rbuf = kzalloc(sizeof(struct lirc_buffer), GFP_KERNEL);
336 if (!rbuf)
337 goto rbuf_alloc_failed;
338
339 rc = lirc_buffer_init(rbuf, sizeof(int), LIRCBUF_SIZE);
340 if (rc)
341 goto rbuf_init_failed;
342
343 features = LIRC_CAN_REC_MODE2;
344 if (dev->tx_ir) {
345 features |= LIRC_CAN_SEND_PULSE;
346 if (dev->s_tx_mask)
347 features |= LIRC_CAN_SET_TRANSMITTER_MASK;
348 if (dev->s_tx_carrier)
349 features |= LIRC_CAN_SET_SEND_CARRIER;
350 if (dev->s_tx_duty_cycle)
351 features |= LIRC_CAN_SET_SEND_DUTY_CYCLE;
352 }
353
354 if (dev->s_rx_carrier_range)
355 features |= LIRC_CAN_SET_REC_CARRIER |
356 LIRC_CAN_SET_REC_CARRIER_RANGE;
357
358 if (dev->s_learning_mode)
359 features |= LIRC_CAN_USE_WIDEBAND_RECEIVER;
360
361 if (dev->s_carrier_report)
362 features |= LIRC_CAN_MEASURE_CARRIER;
363
364 if (dev->max_timeout)
365 features |= LIRC_CAN_SET_REC_TIMEOUT;
366
367 snprintf(drv->name, sizeof(drv->name), "ir-lirc-codec (%s)",
368 dev->driver_name);
369 drv->minor = -1;
370 drv->features = features;
371 drv->data = &dev->raw->lirc;
372 drv->rbuf = rbuf;
373 drv->set_use_inc = &ir_lirc_open;
374 drv->set_use_dec = &ir_lirc_close;
375 drv->code_length = sizeof(struct ir_raw_event) * 8;
376 drv->fops = &lirc_fops;
377 drv->dev = &dev->dev;
378 drv->owner = THIS_MODULE;
379
380 drv->minor = lirc_register_driver(drv);
381 if (drv->minor < 0) {
382 rc = -ENODEV;
383 goto lirc_register_failed;
384 }
385
386 dev->raw->lirc.drv = drv;
387 dev->raw->lirc.dev = dev;
388 return 0;
389
390 lirc_register_failed:
391 rbuf_init_failed:
392 kfree(rbuf);
393 rbuf_alloc_failed:
394 kfree(drv);
395
396 return rc;
397 }
398
ir_lirc_unregister(struct rc_dev * dev)399 static int ir_lirc_unregister(struct rc_dev *dev)
400 {
401 struct lirc_codec *lirc = &dev->raw->lirc;
402
403 lirc_unregister_driver(lirc->drv->minor);
404 lirc_buffer_free(lirc->drv->rbuf);
405 kfree(lirc->drv);
406
407 return 0;
408 }
409
410 static struct ir_raw_handler lirc_handler = {
411 .protocols = RC_BIT_LIRC,
412 .decode = ir_lirc_decode,
413 .raw_register = ir_lirc_register,
414 .raw_unregister = ir_lirc_unregister,
415 };
416
ir_lirc_codec_init(void)417 static int __init ir_lirc_codec_init(void)
418 {
419 ir_raw_handler_register(&lirc_handler);
420
421 printk(KERN_INFO "IR LIRC bridge handler initialized\n");
422 return 0;
423 }
424
ir_lirc_codec_exit(void)425 static void __exit ir_lirc_codec_exit(void)
426 {
427 ir_raw_handler_unregister(&lirc_handler);
428 }
429
430 module_init(ir_lirc_codec_init);
431 module_exit(ir_lirc_codec_exit);
432
433 MODULE_LICENSE("GPL");
434 MODULE_AUTHOR("Jarod Wilson <jarod@redhat.com>");
435 MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
436 MODULE_DESCRIPTION("LIRC IR handler bridge");
437