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

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