target/linux/brcm2708/patches-3.10/0042-lirc-added-support-for-RaspberryPi-GPIO.patch

   1 From b7496d2df33f324ee6854c600944b50a011d95e0 Mon Sep 17 00:00:00 2001
   2 From: Aron Szabo <aron@aron.ws>
   3 Date: Sat, 16 Jun 2012 12:15:55 +0200
   4 Subject: [PATCH 042/174] lirc: added support for RaspberryPi GPIO
   5
   6 ---
   7  drivers/staging/media/lirc/Kconfig    |   6 +
   8  drivers/staging/media/lirc/Makefile   |   1 +
   9  drivers/staging/media/lirc/lirc_rpi.c | 687 ++++++++++++++++++++++++++++++++++
  10  3 files changed, 694 insertions(+)
  11  create mode 100644 drivers/staging/media/lirc/lirc_rpi.c
  12
  13 --- a/drivers/staging/media/lirc/Kconfig
  14 +++ b/drivers/staging/media/lirc/Kconfig
  15 @@ -38,6 +38,12 @@ config LIRC_PARALLEL
  16         help
  17           Driver for Homebrew Parallel Port Receivers
  18
  19 +config LIRC_RPI
  20 +       tristate "Homebrew GPIO Port Receiver/Transmitter for the RaspberryPi"
  21 +       depends on LIRC
  22 +       help
  23 +         Driver for Homebrew GPIO Port Receiver/Transmitter for the RaspberryPi
  24 +
  25  config LIRC_SASEM
  26         tristate "Sasem USB IR Remote"
  27         depends on LIRC && USB
  28 --- a/drivers/staging/media/lirc/Makefile
  29 +++ b/drivers/staging/media/lirc/Makefile
  30 @@ -7,6 +7,7 @@ obj-$(CONFIG_LIRC_BT829)        += lirc_bt829.o
  31  obj-$(CONFIG_LIRC_IGORPLUGUSB) += lirc_igorplugusb.o
  32  obj-$(CONFIG_LIRC_IMON)                += lirc_imon.o
  33  obj-$(CONFIG_LIRC_PARALLEL)    += lirc_parallel.o
  34 +obj-$(CONFIG_LIRC_RPI)         += lirc_rpi.o
  35  obj-$(CONFIG_LIRC_SASEM)       += lirc_sasem.o
  36  obj-$(CONFIG_LIRC_SERIAL)      += lirc_serial.o
  37  obj-$(CONFIG_LIRC_SIR)         += lirc_sir.o
  38 --- /dev/null
  39 +++ b/drivers/staging/media/lirc/lirc_rpi.c
  40 @@ -0,0 +1,687 @@
  41 +/*
  42 + * lirc_rpi.c
  43 + *
  44 + * lirc_rpi - Device driver that records pulse- and pause-lengths
  45 + *           (space-lengths) (just like the lirc_serial driver does)
  46 + *           between GPIO interrupt events on the Raspberry Pi.
  47 + *           Lots of code has been taken from the lirc_serial module,
  48 + *           so I would like say thanks to the authors.
  49 + *
  50 + * Copyright (C) 2012 Aron Robert Szabo <aron@reon.hu>,
  51 + *                   Michael Bishop <cleverca22@gmail.com>
  52 + *  This program is free software; you can redistribute it and/or modify
  53 + *  it under the terms of the GNU General Public License as published by
  54 + *  the Free Software Foundation; either version 2 of the License, or
  55 + *  (at your option) any later version.
  56 + *
  57 + *  This program is distributed in the hope that it will be useful,
  58 + *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  59 + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  60 + *  GNU General Public License for more details.
  61 + *
  62 + *  You should have received a copy of the GNU General Public License
  63 + *  along with this program; if not, write to the Free Software
  64 + *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  65 + */
  66 +
  67 +#include <linux/module.h>
  68 +#include <linux/errno.h>
  69 +#include <linux/interrupt.h>
  70 +#include <linux/sched.h>
  71 +#include <linux/kernel.h>
  72 +#include <linux/time.h>
  73 +#include <linux/string.h>
  74 +#include <linux/delay.h>
  75 +#include <linux/platform_device.h>
  76 +#include <linux/irq.h>
  77 +#include <linux/spinlock.h>
  78 +#include <media/lirc.h>
  79 +#include <media/lirc_dev.h>
  80 +#include <linux/gpio.h>
  81 +
  82 +#define LIRC_DRIVER_NAME "lirc_rpi"
  83 +#define RBUF_LEN 256
  84 +#define LIRC_TRANSMITTER_LATENCY 256
  85 +
  86 +#ifndef MAX_UDELAY_MS
  87 +#define MAX_UDELAY_US 5000
  88 +#else
  89 +#define MAX_UDELAY_US (MAX_UDELAY_MS*1000)
  90 +#endif
  91 +
  92 +#define dprintk(fmt, args...)                                  \
  93 +       do {                                                    \
  94 +               if (debug)                                      \
  95 +                       printk(KERN_DEBUG LIRC_DRIVER_NAME ": " \
  96 +                              fmt, ## args);                   \
  97 +       } while (0)
  98 +
  99 +/* module parameters */
 100 +
 101 +/* set the default GPIO input pin */
 102 +static int gpio_in_pin = 18;
 103 +/* set the default GPIO output pin */
 104 +static int gpio_out_pin = 17;
 105 +/* enable debugging messages */
 106 +static int debug;
 107 +/* -1 = auto, 0 = active high, 1 = active low */
 108 +static int sense = -1;
 109 +/* use softcarrier by default */
 110 +static int softcarrier = 1;
 111 +
 112 +struct gpio_chip *gpiochip;
 113 +struct irq_chip *irqchip;
 114 +struct irq_data *irqdata;
 115 +
 116 +/* forward declarations */
 117 +static long send_pulse(unsigned long length);
 118 +static void send_space(long length);
 119 +static void lirc_rpi_exit(void);
 120 +
 121 +int valid_gpio_pins[] = { 0, 1, 4, 8, 7, 9, 10, 11, 14, 15, 17, 18, 21, 22, 23,
 122 +       24, 25 };
 123 +
 124 +static struct platform_device *lirc_rpi_dev;
 125 +static struct timeval lasttv = { 0, 0 };
 126 +static struct lirc_buffer rbuf;
 127 +static spinlock_t lock;
 128 +
 129 +/* initialized/set in init_timing_params() */
 130 +static unsigned int freq = 38000;
 131 +static unsigned int duty_cycle = 50;
 132 +static unsigned long period;
 133 +static unsigned long pulse_width;
 134 +static unsigned long space_width;
 135 +
 136 +static void safe_udelay(unsigned long usecs)
 137 +{
 138 +       while (usecs > MAX_UDELAY_US) {
 139 +               udelay(MAX_UDELAY_US);
 140 +               usecs -= MAX_UDELAY_US;
 141 +       }
 142 +       udelay(usecs);
 143 +}
 144 +
 145 +static int init_timing_params(unsigned int new_duty_cycle,
 146 +       unsigned int new_freq)
 147 +{
 148 +       /*
 149 +        * period, pulse/space width are kept with 8 binary places -
 150 +        * IE multiplied by 256.
 151 +        */
 152 +       if (256 * 1000000L / new_freq * new_duty_cycle / 100 <=
 153 +           LIRC_TRANSMITTER_LATENCY)
 154 +               return -EINVAL;
 155 +       if (256 * 1000000L / new_freq * (100 - new_duty_cycle) / 100 <=
 156 +           LIRC_TRANSMITTER_LATENCY)
 157 +               return -EINVAL;
 158 +       duty_cycle = new_duty_cycle;
 159 +       freq = new_freq;
 160 +       period = 256 * 1000000L / freq;
 161 +       pulse_width = period * duty_cycle / 100;
 162 +       space_width = period - pulse_width;
 163 +       dprintk("in init_timing_params, freq=%d pulse=%ld, "
 164 +               "space=%ld\n", freq, pulse_width, space_width);
 165 +       return 0;
 166 +}
 167 +
 168 +static long send_pulse_softcarrier(unsigned long length)
 169 +{
 170 +       int flag;
 171 +       unsigned long actual, target, d;
 172 +
 173 +       length <<= 8;
 174 +
 175 +       actual = 0; target = 0; flag = 0;
 176 +       while (actual < length) {
 177 +               if (flag) {
 178 +                       gpiochip->set(gpiochip, gpio_out_pin, 0);
 179 +                       target += space_width;
 180 +               } else {
 181 +                       gpiochip->set(gpiochip, gpio_out_pin, 1);
 182 +                       target += pulse_width;
 183 +               }
 184 +               d = (target - actual -
 185 +                    LIRC_TRANSMITTER_LATENCY + 128) >> 8;
 186 +               /*
 187 +                * Note - we've checked in ioctl that the pulse/space
 188 +                * widths are big enough so that d is > 0
 189 +                */
 190 +               udelay(d);
 191 +               actual += (d << 8) + LIRC_TRANSMITTER_LATENCY;
 192 +               flag = !flag;
 193 +       }
 194 +       return (actual-length) >> 8;
 195 +}
 196 +
 197 +static long send_pulse(unsigned long length)
 198 +{
 199 +       if (length <= 0)
 200 +               return 0;
 201 +
 202 +       if (softcarrier) {
 203 +               return send_pulse_softcarrier(length);
 204 +       } else {
 205 +               gpiochip->set(gpiochip, gpio_out_pin, 1);
 206 +               safe_udelay(length);
 207 +               return 0;
 208 +       }
 209 +}
 210 +
 211 +static void send_space(long length)
 212 +{
 213 +       gpiochip->set(gpiochip, gpio_out_pin, 0);
 214 +       if (length <= 0)
 215 +               return;
 216 +       safe_udelay(length);
 217 +}
 218 +
 219 +static void rbwrite(int l)
 220 +{
 221 +       if (lirc_buffer_full(&rbuf)) {
 222 +               /* no new signals will be accepted */
 223 +               dprintk("Buffer overrun\n");
 224 +               return;
 225 +       }
 226 +       lirc_buffer_write(&rbuf, (void *)&l);
 227 +}
 228 +
 229 +static void frbwrite(int l)
 230 +{
 231 +       /* simple noise filter */
 232 +       static int pulse, space;
 233 +       static unsigned int ptr;
 234 +
 235 +       if (ptr > 0 && (l & PULSE_BIT)) {
 236 +               pulse += l & PULSE_MASK;
 237 +               if (pulse > 250) {
 238 +                       rbwrite(space);
 239 +                       rbwrite(pulse | PULSE_BIT);
 240 +                       ptr = 0;
 241 +                       pulse = 0;
 242 +               }
 243 +               return;
 244 +       }
 245 +       if (!(l & PULSE_BIT)) {
 246 +               if (ptr == 0) {
 247 +                       if (l > 20000) {
 248 +                               space = l;
 249 +                               ptr++;
 250 +                               return;
 251 +                       }
 252 +               } else {
 253 +                       if (l > 20000) {
 254 +                               space += pulse;
 255 +                               if (space > PULSE_MASK)
 256 +                                       space = PULSE_MASK;
 257 +                               space += l;
 258 +                               if (space > PULSE_MASK)
 259 +                                       space = PULSE_MASK;
 260 +                               pulse = 0;
 261 +                               return;
 262 +                       }
 263 +                       rbwrite(space);
 264 +                       rbwrite(pulse | PULSE_BIT);
 265 +                       ptr = 0;
 266 +                       pulse = 0;
 267 +               }
 268 +       }
 269 +       rbwrite(l);
 270 +}
 271 +
 272 +static irqreturn_t irq_handler(int i, void *blah, struct pt_regs *regs)
 273 +{
 274 +       struct timeval tv;
 275 +       long deltv;
 276 +       int data;
 277 +       int signal;
 278 +
 279 +       /* use the GPIO signal level */
 280 +       signal = gpiochip->get(gpiochip, gpio_in_pin);
 281 +
 282 +       /* unmask the irq */
 283 +       irqchip->irq_unmask(irqdata);
 284 +
 285 +       if (sense != -1) {
 286 +               /* get current time */
 287 +               do_gettimeofday(&tv);
 288 +
 289 +               /* calc time since last interrupt in microseconds */
 290 +               deltv = tv.tv_sec-lasttv.tv_sec;
 291 +               if (tv.tv_sec < lasttv.tv_sec ||
 292 +                   (tv.tv_sec == lasttv.tv_sec &&
 293 +                    tv.tv_usec < lasttv.tv_usec)) {
 294 +                       printk(KERN_WARNING LIRC_DRIVER_NAME
 295 +                              ": AIEEEE: your clock just jumped backwards\n");
 296 +                       printk(KERN_WARNING LIRC_DRIVER_NAME
 297 +                              ": %d %d %lx %lx %lx %lx\n", signal, sense,
 298 +                              tv.tv_sec, lasttv.tv_sec,
 299 +                              tv.tv_usec, lasttv.tv_usec);
 300 +                       data = PULSE_MASK;
 301 +               } else if (deltv > 15) {
 302 +                       data = PULSE_MASK; /* really long time */
 303 +                       if (!(signal^sense)) {
 304 +                               /* sanity check */
 305 +                               printk(KERN_WARNING LIRC_DRIVER_NAME
 306 +                                      ": AIEEEE: %d %d %lx %lx %lx %lx\n",
 307 +                                      signal, sense, tv.tv_sec, lasttv.tv_sec,
 308 +                                      tv.tv_usec, lasttv.tv_usec);
 309 +                               /*
 310 +                                * detecting pulse while this
 311 +                                * MUST be a space!
 312 +                                */
 313 +                               sense = sense ? 0 : 1;
 314 +                       }
 315 +               } else {
 316 +                       data = (int) (deltv*1000000 +
 317 +                                     (tv.tv_usec - lasttv.tv_usec));
 318 +               }
 319 +               frbwrite(signal^sense ? data : (data|PULSE_BIT));
 320 +               lasttv = tv;
 321 +               wake_up_interruptible(&rbuf.wait_poll);
 322 +       }
 323 +
 324 +       return IRQ_HANDLED;
 325 +}
 326 +
 327 +static int is_right_chip(struct gpio_chip *chip, void *data)
 328 +{
 329 +       dprintk("is_right_chip %s %d\n", chip->label, strcmp(data, chip->label));
 330 +
 331 +       if (strcmp(data, chip->label) == 0)
 332 +               return 1;
 333 +       return 0;
 334 +}
 335 +
 336 +static int init_port(void)
 337 +{
 338 +       int i, nlow, nhigh, ret, irq;
 339 +
 340 +       gpiochip = gpiochip_find("bcm2708_gpio", is_right_chip);
 341 +
 342 +       if (!gpiochip)
 343 +               return -ENODEV;
 344 +
 345 +       if (gpio_request(gpio_out_pin, LIRC_DRIVER_NAME " ir/out")) {
 346 +               printk(KERN_ALERT LIRC_DRIVER_NAME
 347 +                      ": cant claim gpio pin %d\n", gpio_out_pin);
 348 +               ret = -ENODEV;
 349 +               goto exit_init_port;
 350 +       }
 351 +
 352 +       if (gpio_request(gpio_in_pin, LIRC_DRIVER_NAME " ir/in")) {
 353 +               printk(KERN_ALERT LIRC_DRIVER_NAME
 354 +                      ": cant claim gpio pin %d\n", gpio_in_pin);
 355 +               ret = -ENODEV;
 356 +               goto exit_gpio_free_out_pin;
 357 +       }
 358 +
 359 +       gpiochip->direction_input(gpiochip, gpio_in_pin);
 360 +       gpiochip->direction_output(gpiochip, gpio_out_pin, 1);
 361 +       gpiochip->set(gpiochip, gpio_out_pin, 0);
 362 +
 363 +       irq = gpiochip->to_irq(gpiochip, gpio_in_pin);
 364 +       dprintk("to_irq %d\n", irq);
 365 +       irqdata = irq_get_irq_data(irq);
 366 +
 367 +       if (irqdata && irqdata->chip) {
 368 +               irqchip = irqdata->chip;
 369 +       } else {
 370 +               ret = -ENODEV;
 371 +               goto exit_gpio_free_in_pin;
 372 +       }
 373 +
 374 +       /* if pin is high, then this must be an active low receiver. */
 375 +       if (sense == -1) {
 376 +               /* wait 1/2 sec for the power supply */
 377 +               msleep(500);
 378 +
 379 +               /*
 380 +                * probe 9 times every 0.04s, collect "votes" for
 381 +                * active high/low
 382 +                */
 383 +               nlow = 0;
 384 +               nhigh = 0;
 385 +               for (i = 0; i < 9; i++) {
 386 +                       if (gpiochip->get(gpiochip, gpio_in_pin))
 387 +                               nlow++;
 388 +                       else
 389 +                               nhigh++;
 390 +                       msleep(40);
 391 +               }
 392 +               sense = (nlow >= nhigh ? 1 : 0);
 393 +               printk(KERN_INFO LIRC_DRIVER_NAME
 394 +                      ": auto-detected active %s receiver on GPIO pin %d\n",
 395 +                      sense ? "low" : "high", gpio_in_pin);
 396 +       } else {
 397 +               printk(KERN_INFO LIRC_DRIVER_NAME
 398 +                      ": manually using active %s receiver on GPIO pin %d\n",
 399 +                      sense ? "low" : "high", gpio_in_pin);
 400 +       }
 401 +
 402 +       return 0;
 403 +
 404 +       exit_gpio_free_in_pin:
 405 +       gpio_free(gpio_in_pin);
 406 +
 407 +       exit_gpio_free_out_pin:
 408 +       gpio_free(gpio_out_pin);
 409 +
 410 +       exit_init_port:
 411 +       return ret;
 412 +}
 413 +
 414 +// called when the character device is opened
 415 +static int set_use_inc(void *data)
 416 +{
 417 +       int result;
 418 +       unsigned long flags;
 419 +
 420 +       /* initialize timestamp */
 421 +       do_gettimeofday(&lasttv);
 422 +
 423 +       result = request_irq(gpiochip->to_irq(gpiochip, gpio_in_pin),
 424 +                            (irq_handler_t) irq_handler, 0,
 425 +                            LIRC_DRIVER_NAME, (void*) 0);
 426 +
 427 +       switch (result) {
 428 +       case -EBUSY:
 429 +               printk(KERN_ERR LIRC_DRIVER_NAME
 430 +                      ": IRQ %d is busy\n",
 431 +                      gpiochip->to_irq(gpiochip, gpio_in_pin));
 432 +               return -EBUSY;
 433 +       case -EINVAL:
 434 +               printk(KERN_ERR LIRC_DRIVER_NAME
 435 +                      ": Bad irq number or handler\n");
 436 +               return -EINVAL;
 437 +       default:
 438 +               dprintk("Interrupt %d obtained\n",
 439 +                       gpiochip->to_irq(gpiochip, gpio_in_pin));
 440 +               break;
 441 +       };
 442 +
 443 +       /* initialize pulse/space widths */
 444 +       init_timing_params(duty_cycle, freq);
 445 +
 446 +       spin_lock_irqsave(&lock, flags);
 447 +
 448 +       /* GPIO Pin Falling/Rising Edge Detect Enable */
 449 +       irqchip->irq_set_type(irqdata,
 450 +                             IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING);
 451 +
 452 +       /* unmask the irq */
 453 +       irqchip->irq_unmask(irqdata);
 454 +
 455 +       spin_unlock_irqrestore(&lock, flags);
 456 +
 457 +       return 0;
 458 +}
 459 +
 460 +static void set_use_dec(void *data)
 461 +{
 462 +       unsigned long flags;
 463 +
 464 +       spin_lock_irqsave(&lock, flags);
 465 +
 466 +       /* GPIO Pin Falling/Rising Edge Detect Disable */
 467 +       irqchip->irq_set_type(irqdata, 0);
 468 +       irqchip->irq_mask(irqdata);
 469 +
 470 +       spin_unlock_irqrestore(&lock, flags);
 471 +
 472 +       free_irq(gpiochip->to_irq(gpiochip, gpio_in_pin), (void *) 0);
 473 +
 474 +       dprintk(KERN_INFO LIRC_DRIVER_NAME
 475 +               ": freed IRQ %d\n", gpiochip->to_irq(gpiochip, gpio_in_pin));
 476 +}
 477 +
 478 +static ssize_t lirc_write(struct file *file, const char *buf,
 479 +       size_t n, loff_t *ppos)
 480 +{
 481 +       int i, count;
 482 +       unsigned long flags;
 483 +       long delta = 0;
 484 +       int *wbuf;
 485 +
 486 +       count = n / sizeof(int);
 487 +       if (n % sizeof(int) || count % 2 == 0)
 488 +               return -EINVAL;
 489 +       wbuf = memdup_user(buf, n);
 490 +       if (IS_ERR(wbuf))
 491 +               return PTR_ERR(wbuf);
 492 +       spin_lock_irqsave(&lock, flags);
 493 +
 494 +       for (i = 0; i < count; i++) {
 495 +               if (i%2)
 496 +                       send_space(wbuf[i] - delta);
 497 +               else
 498 +                       delta = send_pulse(wbuf[i]);
 499 +       }
 500 +       gpiochip->set(gpiochip, gpio_out_pin, 0);
 501 +
 502 +       spin_unlock_irqrestore(&lock, flags);
 503 +       kfree(wbuf);
 504 +       return n;
 505 +}
 506 +
 507 +static long lirc_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
 508 +{
 509 +       int result;
 510 +       __u32 value;
 511 +
 512 +       switch (cmd) {
 513 +       case LIRC_GET_SEND_MODE:
 514 +               return -ENOIOCTLCMD;
 515 +               break;
 516 +
 517 +       case LIRC_SET_SEND_MODE:
 518 +               result = get_user(value, (__u32 *) arg);
 519 +               if (result)
 520 +                       return result;
 521 +               /* only LIRC_MODE_PULSE supported */
 522 +               if (value != LIRC_MODE_PULSE)
 523 +                       return -ENOSYS;
 524 +               break;
 525 +
 526 +       case LIRC_GET_LENGTH:
 527 +               return -ENOSYS;
 528 +               break;
 529 +
 530 +       case LIRC_SET_SEND_DUTY_CYCLE:
 531 +               dprintk("SET_SEND_DUTY_CYCLE\n");
 532 +               result = get_user(value, (__u32 *) arg);
 533 +               if (result)
 534 +                       return result;
 535 +               if (value <= 0 || value > 100)
 536 +                       return -EINVAL;
 537 +               return init_timing_params(value, freq);
 538 +               break;
 539 +
 540 +       case LIRC_SET_SEND_CARRIER:
 541 +               dprintk("SET_SEND_CARRIER\n");
 542 +               result = get_user(value, (__u32 *) arg);
 543 +               if (result)
 544 +                       return result;
 545 +               if (value > 500000 || value < 20000)
 546 +                       return -EINVAL;
 547 +               return init_timing_params(duty_cycle, value);
 548 +               break;
 549 +
 550 +       default:
 551 +               return lirc_dev_fop_ioctl(filep, cmd, arg);
 552 +       }
 553 +       return 0;
 554 +}
 555 +
 556 +static const struct file_operations lirc_fops = {
 557 +       .owner          = THIS_MODULE,
 558 +       .write          = lirc_write,
 559 +       .unlocked_ioctl = lirc_ioctl,
 560 +       .read           = lirc_dev_fop_read,
 561 +       .poll           = lirc_dev_fop_poll,
 562 +       .open           = lirc_dev_fop_open,
 563 +       .release        = lirc_dev_fop_close,
 564 +       .llseek         = no_llseek,
 565 +};
 566 +
 567 +static struct lirc_driver driver = {
 568 +       .name           = LIRC_DRIVER_NAME,
 569 +       .minor          = -1,
 570 +       .code_length    = 1,
 571 +       .sample_rate    = 0,
 572 +       .data           = NULL,
 573 +       .add_to_buf     = NULL,
 574 +       .rbuf           = &rbuf,
 575 +       .set_use_inc    = set_use_inc,
 576 +       .set_use_dec    = set_use_dec,
 577 +       .fops           = &lirc_fops,
 578 +       .dev            = NULL,
 579 +       .owner          = THIS_MODULE,
 580 +};
 581 +
 582 +static struct platform_driver lirc_rpi_driver = {
 583 +       .driver = {
 584 +               .name   = LIRC_DRIVER_NAME,
 585 +               .owner  = THIS_MODULE,
 586 +       },
 587 +};
 588 +
 589 +static int __init lirc_rpi_init(void)
 590 +{
 591 +       int result;
 592 +
 593 +       /* Init read buffer. */
 594 +       result = lirc_buffer_init(&rbuf, sizeof(int), RBUF_LEN);
 595 +       if (result < 0)
 596 +               return -ENOMEM;
 597 +
 598 +       result = platform_driver_register(&lirc_rpi_driver);
 599 +       if (result) {
 600 +               printk(KERN_ERR LIRC_DRIVER_NAME
 601 +                      ": lirc register returned %d\n", result);
 602 +               goto exit_buffer_free;
 603 +       }
 604 +
 605 +       lirc_rpi_dev = platform_device_alloc(LIRC_DRIVER_NAME, 0);
 606 +       if (!lirc_rpi_dev) {
 607 +               result = -ENOMEM;
 608 +               goto exit_driver_unregister;
 609 +       }
 610 +
 611 +       result = platform_device_add(lirc_rpi_dev);
 612 +       if (result)
 613 +               goto exit_device_put;
 614 +
 615 +       return 0;
 616 +
 617 +       exit_device_put:
 618 +       platform_device_put(lirc_rpi_dev);
 619 +
 620 +       exit_driver_unregister:
 621 +       platform_driver_unregister(&lirc_rpi_driver);
 622 +
 623 +       exit_buffer_free:
 624 +       lirc_buffer_free(&rbuf);
 625 +
 626 +       return result;
 627 +}
 628 +
 629 +static void lirc_rpi_exit(void)
 630 +{
 631 +       gpio_free(gpio_out_pin);
 632 +       gpio_free(gpio_in_pin);
 633 +       platform_device_unregister(lirc_rpi_dev);
 634 +       platform_driver_unregister(&lirc_rpi_driver);
 635 +       lirc_buffer_free(&rbuf);
 636 +}
 637 +
 638 +static int __init lirc_rpi_init_module(void)
 639 +{
 640 +       int result, i;
 641 +
 642 +       result = lirc_rpi_init();
 643 +       if (result)
 644 +               return result;
 645 +
 646 +       /* check if the module received valid gpio pin numbers */
 647 +       result = 0;
 648 +       if (gpio_in_pin != gpio_out_pin) {
 649 +               for(i = 0; (i < ARRAY_SIZE(valid_gpio_pins)) && (result != 2); i++) {
 650 +                       if (gpio_in_pin == valid_gpio_pins[i] ||
 651 +                          gpio_out_pin == valid_gpio_pins[i]) {
 652 +                               result++;
 653 +                       }
 654 +               }
 655 +       }
 656 +
 657 +       if (result != 2) {
 658 +               result = -EINVAL;
 659 +               printk(KERN_ERR LIRC_DRIVER_NAME
 660 +                      ": invalid GPIO pin(s) specified!\n");
 661 +               goto exit_rpi;
 662 +       }
 663 +
 664 +       driver.features = LIRC_CAN_SET_SEND_DUTY_CYCLE |
 665 +                         LIRC_CAN_SET_SEND_CARRIER |
 666 +                         LIRC_CAN_SEND_PULSE |
 667 +                         LIRC_CAN_REC_MODE2;
 668 +
 669 +       driver.dev = &lirc_rpi_dev->dev;
 670 +       driver.minor = lirc_register_driver(&driver);
 671 +
 672 +       if (driver.minor < 0) {
 673 +               printk(KERN_ERR LIRC_DRIVER_NAME
 674 +                      ": device registration failed with %d\n", result);
 675 +               result = -EIO;
 676 +               goto exit_rpi;
 677 +       }
 678 +
 679 +       printk(KERN_INFO LIRC_DRIVER_NAME ": driver registered!\n");
 680 +
 681 +       result = init_port();
 682 +       if (result < 0)
 683 +               goto exit_rpi;
 684 +
 685 +       return 0;
 686 +
 687 +       exit_rpi:
 688 +       lirc_rpi_exit();
 689 +
 690 +       return result;
 691 +}
 692 +
 693 +static void __exit lirc_rpi_exit_module(void)
 694 +{
 695 +       lirc_rpi_exit();
 696 +
 697 +       lirc_unregister_driver(driver.minor);
 698 +       printk(KERN_INFO LIRC_DRIVER_NAME ": cleaned up module\n");
 699 +}
 700 +
 701 +module_init(lirc_rpi_init_module);
 702 +module_exit(lirc_rpi_exit_module);
 703 +
 704 +MODULE_DESCRIPTION("Infra-red receiver and blaster driver for Raspberry Pi GPIO.");
 705 +MODULE_AUTHOR("Aron Robert Szabo <aron@reon.hu>");
 706 +MODULE_AUTHOR("Michael Bishop <cleverca22@gmail.com>");
 707 +MODULE_LICENSE("GPL");
 708 +
 709 +module_param(gpio_out_pin, int, S_IRUGO);
 710 +MODULE_PARM_DESC(gpio_out_pin, "GPIO output/transmitter pin number of the BCM"
 711 +                " processor. Valid pin numbers are: 0, 1, 4, 8, 7, 9, 10, 11,"
 712 +                " 14, 15, 17, 18, 21, 22, 23, 24, 25, default 17");
 713 +
 714 +module_param(gpio_in_pin, int, S_IRUGO);
 715 +MODULE_PARM_DESC(gpio_in_pin, "GPIO input pin number of the BCM processor."
 716 +                " Valid pin numbers are: 0, 1, 4, 8, 7, 9, 10, 11, 14, 15,"
 717 +                " 17, 18, 21, 22, 23, 24, 25, default 18");
 718 +
 719 +module_param(sense, bool, S_IRUGO);
 720 +MODULE_PARM_DESC(sense, "Override autodetection of IR receiver circuit"
 721 +                " (0 = active high, 1 = active low )");
 722 +
 723 +module_param(softcarrier, bool, S_IRUGO);
 724 +MODULE_PARM_DESC(softcarrier, "Software carrier (0 = off, 1 = on, default on)");
 725 +
 726 +module_param(debug, bool, S_IRUGO | S_IWUSR);
 727 +MODULE_PARM_DESC(debug, "Enable debugging messages");