drivers/media/rc/ir-lirc-codec.c

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