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