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 <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  */
  33 static 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
 102 static 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
 138 out:
 139         kfree(txbuf);
 140         return ret;
 141 }
 142
 143 static 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
 275 static int ir_lirc_open(void *data)
 276 {
 277         return 0;
 278 }
 279
 280 static void ir_lirc_close(void *data)
 281 {
 282         return;
 283 }
 284
 285 static 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
 299 static 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
 365 lirc_register_failed:
 366 rbuf_init_failed:
 367         kfree(rbuf);
 368 rbuf_alloc_failed:
 369         kfree(drv);
 370
 371         return rc;
 372 }
 373
 374 static 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
 385 static 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
 392 static 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
 400 static void __exit ir_lirc_codec_exit(void)
 401 {
 402         ir_raw_handler_unregister(&lirc_handler);
 403 }
 404
 405 module_init(ir_lirc_codec_init);
 406 module_exit(ir_lirc_codec_exit);
 407
 408 MODULE_LICENSE("GPL");
 409 MODULE_AUTHOR("Jarod Wilson <jarod@redhat.com>");
 410 MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
 411 MODULE_DESCRIPTION("LIRC IR handler bridge");