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 */
 33static 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->raw->enabled_protocols & RC_TYPE_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
102static 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 = 0;
109	size_t count;
110
111	lirc = lirc_get_pdata(file);
112	if (!lirc)
113		return -EFAULT;
114
115	if (n < sizeof(unsigned) || n % sizeof(unsigned))
116		return -EINVAL;
117
118	count = n / sizeof(unsigned);
119	if (count > LIRCBUF_SIZE || count % 2 == 0)
120		return -EINVAL;
121
122	txbuf = memdup_user(buf, n);
123	if (IS_ERR(txbuf))
124		return PTR_ERR(txbuf);
125
126	dev = lirc->dev;
127	if (!dev) {
128		ret = -EFAULT;
129		goto out;
130	}
131
132	if (dev->tx_ir)
133		ret = dev->tx_ir(dev, txbuf, count);
134
135	if (ret > 0)
136		ret *= sizeof(unsigned);
137
138out:
139	kfree(txbuf);
140	return ret;
141}
142
143static long ir_lirc_ioctl(struct file *filep, unsigned int cmd,
144			unsigned long arg)
145{
146	struct lirc_codec *lirc;
147	struct rc_dev *dev;
148	u32 __user *argp = (u32 __user *)(arg);
149	int ret = 0;
150	__u32 val = 0, tmp;
151
152	lirc = lirc_get_pdata(filep);
153	if (!lirc)
154		return -EFAULT;
155
156	dev = lirc->dev;
157	if (!dev)
158		return -EFAULT;
159
160	if (_IOC_DIR(cmd) & _IOC_WRITE) {
161		ret = get_user(val, argp);
162		if (ret)
163			return ret;
164	}
165
166	switch (cmd) {
167
168	/* legacy support */
169	case LIRC_GET_SEND_MODE:
170		val = LIRC_CAN_SEND_PULSE & LIRC_CAN_SEND_MASK;
171		break;
172
173	case LIRC_SET_SEND_MODE:
174		if (val != (LIRC_MODE_PULSE & LIRC_CAN_SEND_MASK))
175			return -EINVAL;
176		return 0;
177
178	/* TX settings */
179	case LIRC_SET_TRANSMITTER_MASK:
180		if (!dev->s_tx_mask)
181			return -EINVAL;
182
183		return dev->s_tx_mask(dev, val);
184
185	case LIRC_SET_SEND_CARRIER:
186		if (!dev->s_tx_carrier)
187			return -EINVAL;
188
189		return dev->s_tx_carrier(dev, val);
190
191	case LIRC_SET_SEND_DUTY_CYCLE:
192		if (!dev->s_tx_duty_cycle)
193			return -ENOSYS;
194
195		if (val <= 0 || val >= 100)
196			return -EINVAL;
197
198		return dev->s_tx_duty_cycle(dev, val);
199
200	/* RX settings */
201	case LIRC_SET_REC_CARRIER:
202		if (!dev->s_rx_carrier_range)
203			return -ENOSYS;
204
205		if (val <= 0)
206			return -EINVAL;
207
208		return dev->s_rx_carrier_range(dev,
209					       dev->raw->lirc.carrier_low,
210					       val);
211
212	case LIRC_SET_REC_CARRIER_RANGE:
213		if (val <= 0)
214			return -EINVAL;
215
216		dev->raw->lirc.carrier_low = val;
217		return 0;
218
219	case LIRC_GET_REC_RESOLUTION:
220		val = dev->rx_resolution;
221		break;
222
223	case LIRC_SET_WIDEBAND_RECEIVER:
224		if (!dev->s_learning_mode)
225			return -ENOSYS;
226
227		return dev->s_learning_mode(dev, !!val);
228
229	case LIRC_SET_MEASURE_CARRIER_MODE:
230		if (!dev->s_carrier_report)
231			return -ENOSYS;
232
233		return dev->s_carrier_report(dev, !!val);
234
235	/* Generic timeout support */
236	case LIRC_GET_MIN_TIMEOUT:
237		if (!dev->max_timeout)
238			return -ENOSYS;
239		val = dev->min_timeout / 1000;
240		break;
241
242	case LIRC_GET_MAX_TIMEOUT:
243		if (!dev->max_timeout)
244			return -ENOSYS;
245		val = dev->max_timeout / 1000;
246		break;
247
248	case LIRC_SET_REC_TIMEOUT:
249		if (!dev->max_timeout)
250			return -ENOSYS;
251
252		tmp = val * 1000;
253
254		if (tmp < dev->min_timeout ||
255		    tmp > dev->max_timeout)
256				return -EINVAL;
257
258		dev->timeout = tmp;
259		break;
260
261	case LIRC_SET_REC_TIMEOUT_REPORTS:
262		lirc->send_timeout_reports = !!val;
263		break;
264
265	default:
266		return lirc_dev_fop_ioctl(filep, cmd, arg);
267	}
268
269	if (_IOC_DIR(cmd) & _IOC_READ)
270		ret = put_user(val, argp);
271
272	return ret;
273}
274
275static int ir_lirc_open(void *data)
276{
277	return 0;
278}
279
280static void ir_lirc_close(void *data)
281{
282	return;
283}
284
285static struct file_operations lirc_fops = {
286	.owner		= THIS_MODULE,
287	.write		= ir_lirc_transmit_ir,
288	.unlocked_ioctl	= ir_lirc_ioctl,
289#ifdef CONFIG_COMPAT
290	.compat_ioctl	= ir_lirc_ioctl,
291#endif
292	.read		= lirc_dev_fop_read,
293	.poll		= lirc_dev_fop_poll,
294	.open		= lirc_dev_fop_open,
295	.release	= lirc_dev_fop_close,
296	.llseek		= no_llseek,
297};
298
299static int ir_lirc_register(struct rc_dev *dev)
300{
301	struct lirc_driver *drv;
302	struct lirc_buffer *rbuf;
303	int rc = -ENOMEM;
304	unsigned long features;
305
306	drv = kzalloc(sizeof(struct lirc_driver), GFP_KERNEL);
307	if (!drv)
308		return rc;
309
310	rbuf = kzalloc(sizeof(struct lirc_buffer), GFP_KERNEL);
311	if (!rbuf)
312		goto rbuf_alloc_failed;
313
314	rc = lirc_buffer_init(rbuf, sizeof(int), LIRCBUF_SIZE);
315	if (rc)
316		goto rbuf_init_failed;
317
318	features = LIRC_CAN_REC_MODE2;
319	if (dev->tx_ir) {
320		features |= LIRC_CAN_SEND_PULSE;
321		if (dev->s_tx_mask)
322			features |= LIRC_CAN_SET_TRANSMITTER_MASK;
323		if (dev->s_tx_carrier)
324			features |= LIRC_CAN_SET_SEND_CARRIER;
325		if (dev->s_tx_duty_cycle)
326			features |= LIRC_CAN_SET_SEND_DUTY_CYCLE;
327	}
328
329	if (dev->s_rx_carrier_range)
330		features |= LIRC_CAN_SET_REC_CARRIER |
331			LIRC_CAN_SET_REC_CARRIER_RANGE;
332
333	if (dev->s_learning_mode)
334		features |= LIRC_CAN_USE_WIDEBAND_RECEIVER;
335
336	if (dev->s_carrier_report)
337		features |= LIRC_CAN_MEASURE_CARRIER;
338
339	if (dev->max_timeout)
340		features |= LIRC_CAN_SET_REC_TIMEOUT;
341
342	snprintf(drv->name, sizeof(drv->name), "ir-lirc-codec (%s)",
343		 dev->driver_name);
344	drv->minor = -1;
345	drv->features = features;
346	drv->data = &dev->raw->lirc;
347	drv->rbuf = rbuf;
348	drv->set_use_inc = &ir_lirc_open;
349	drv->set_use_dec = &ir_lirc_close;
350	drv->code_length = sizeof(struct ir_raw_event) * 8;
351	drv->fops = &lirc_fops;
352	drv->dev = &dev->dev;
353	drv->owner = THIS_MODULE;
354
355	drv->minor = lirc_register_driver(drv);
356	if (drv->minor < 0) {
357		rc = -ENODEV;
358		goto lirc_register_failed;
359	}
360
361	dev->raw->lirc.drv = drv;
362	dev->raw->lirc.dev = dev;
363	return 0;
364
365lirc_register_failed:
366rbuf_init_failed:
367	kfree(rbuf);
368rbuf_alloc_failed:
369	kfree(drv);
370
371	return rc;
372}
373
374static int ir_lirc_unregister(struct rc_dev *dev)
375{
376	struct lirc_codec *lirc = &dev->raw->lirc;
377
378	lirc_unregister_driver(lirc->drv->minor);
379	lirc_buffer_free(lirc->drv->rbuf);
380	kfree(lirc->drv);
381
382	return 0;
383}
384
385static struct ir_raw_handler lirc_handler = {
386	.protocols	= RC_TYPE_LIRC,
387	.decode		= ir_lirc_decode,
388	.raw_register	= ir_lirc_register,
389	.raw_unregister	= ir_lirc_unregister,
390};
391
392static int __init ir_lirc_codec_init(void)
393{
394	ir_raw_handler_register(&lirc_handler);
395
396	printk(KERN_INFO "IR LIRC bridge handler initialized\n");
397	return 0;
398}
399
400static void __exit ir_lirc_codec_exit(void)
401{
402	ir_raw_handler_unregister(&lirc_handler);
403}
404
405module_init(ir_lirc_codec_init);
406module_exit(ir_lirc_codec_exit);
407
408MODULE_LICENSE("GPL");
409MODULE_AUTHOR("Jarod Wilson <jarod@redhat.com>");
410MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
411MODULE_DESCRIPTION("LIRC IR handler bridge");