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