drivers/media/rc/ir-rx51.c

   1 /*
   2  *  Copyright (C) 2008 Nokia Corporation
   3  *
   4  *  Based on lirc_serial.c
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/uaccess.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/sched.h>
  27 #include <linux/wait.h>
  28
  29 #include <plat/dmtimer.h>
  30 #include <plat/clock.h>
  31
  32 #include <media/lirc.h>
  33 #include <media/lirc_dev.h>
  34 #include <media/ir-rx51.h>
  35
  36 #define LIRC_RX51_DRIVER_FEATURES (LIRC_CAN_SET_SEND_DUTY_CYCLE |       \
  37                                    LIRC_CAN_SET_SEND_CARRIER |          \
  38                                    LIRC_CAN_SEND_PULSE)
  39
  40 #define DRIVER_NAME "lirc_rx51"
  41
  42 #define WBUF_LEN 256
  43
  44 #define TIMER_MAX_VALUE 0xffffffff
  45
  46 struct lirc_rx51 {
  47         struct omap_dm_timer *pwm_timer;
  48         struct omap_dm_timer *pulse_timer;
  49         struct device        *dev;
  50         struct lirc_rx51_platform_data *pdata;
  51         wait_queue_head_t     wqueue;
  52
  53         unsigned long   fclk_khz;
  54         unsigned int    freq;           /* carrier frequency */
  55         unsigned int    duty_cycle;     /* carrier duty cycle */
  56         unsigned int    irq_num;
  57         unsigned int    match;
  58         int             wbuf[WBUF_LEN];
  59         int             wbuf_index;
  60         unsigned long   device_is_open;
  61         int             pwm_timer_num;
  62 };
  63
  64 static void lirc_rx51_on(struct lirc_rx51 *lirc_rx51)
  65 {
  66         omap_dm_timer_set_pwm(lirc_rx51->pwm_timer, 0, 1,
  67                               OMAP_TIMER_TRIGGER_OVERFLOW_AND_COMPARE);
  68 }
  69
  70 static void lirc_rx51_off(struct lirc_rx51 *lirc_rx51)
  71 {
  72         omap_dm_timer_set_pwm(lirc_rx51->pwm_timer, 0, 1,
  73                               OMAP_TIMER_TRIGGER_NONE);
  74 }
  75
  76 static int init_timing_params(struct lirc_rx51 *lirc_rx51)
  77 {
  78         u32 load, match;
  79
  80         load = -(lirc_rx51->fclk_khz * 1000 / lirc_rx51->freq);
  81         match = -(lirc_rx51->duty_cycle * -load / 100);
  82         omap_dm_timer_set_load(lirc_rx51->pwm_timer, 1, load);
  83         omap_dm_timer_set_match(lirc_rx51->pwm_timer, 1, match);
  84         omap_dm_timer_write_counter(lirc_rx51->pwm_timer, TIMER_MAX_VALUE - 2);
  85         omap_dm_timer_start(lirc_rx51->pwm_timer);
  86         omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0);
  87         omap_dm_timer_start(lirc_rx51->pulse_timer);
  88
  89         lirc_rx51->match = 0;
  90
  91         return 0;
  92 }
  93
  94 #define tics_after(a, b) ((long)(b) - (long)(a) < 0)
  95
  96 static int pulse_timer_set_timeout(struct lirc_rx51 *lirc_rx51, int usec)
  97 {
  98         int counter;
  99
 100         BUG_ON(usec < 0);
 101
 102         if (lirc_rx51->match == 0)
 103                 counter = omap_dm_timer_read_counter(lirc_rx51->pulse_timer);
 104         else
 105                 counter = lirc_rx51->match;
 106
 107         counter += (u32)(lirc_rx51->fclk_khz * usec / (1000));
 108         omap_dm_timer_set_match(lirc_rx51->pulse_timer, 1, counter);
 109         omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer,
 110                                      OMAP_TIMER_INT_MATCH);
 111         if (tics_after(omap_dm_timer_read_counter(lirc_rx51->pulse_timer),
 112                        counter)) {
 113                 return 1;
 114         }
 115         return 0;
 116 }
 117
 118 static irqreturn_t lirc_rx51_interrupt_handler(int irq, void *ptr)
 119 {
 120         unsigned int retval;
 121         struct lirc_rx51 *lirc_rx51 = ptr;
 122
 123         retval = omap_dm_timer_read_status(lirc_rx51->pulse_timer);
 124         if (!retval)
 125                 return IRQ_NONE;
 126
 127         if (retval & ~OMAP_TIMER_INT_MATCH)
 128                 dev_err_ratelimited(lirc_rx51->dev,
 129                                 ": Unexpected interrupt source: %x\n", retval);
 130
 131         omap_dm_timer_write_status(lirc_rx51->pulse_timer,
 132                                 OMAP_TIMER_INT_MATCH    |
 133                                 OMAP_TIMER_INT_OVERFLOW |
 134                                 OMAP_TIMER_INT_CAPTURE);
 135         if (lirc_rx51->wbuf_index < 0) {
 136                 dev_err_ratelimited(lirc_rx51->dev,
 137                                 ": BUG wbuf_index has value of %i\n",
 138                                 lirc_rx51->wbuf_index);
 139                 goto end;
 140         }
 141
 142         /*
 143          * If we happen to hit an odd latency spike, loop through the
 144          * pulses until we catch up.
 145          */
 146         do {
 147                 if (lirc_rx51->wbuf_index >= WBUF_LEN)
 148                         goto end;
 149                 if (lirc_rx51->wbuf[lirc_rx51->wbuf_index] == -1)
 150                         goto end;
 151
 152                 if (lirc_rx51->wbuf_index % 2)
 153                         lirc_rx51_off(lirc_rx51);
 154                 else
 155                         lirc_rx51_on(lirc_rx51);
 156
 157                 retval = pulse_timer_set_timeout(lirc_rx51,
 158                                         lirc_rx51->wbuf[lirc_rx51->wbuf_index]);
 159                 lirc_rx51->wbuf_index++;
 160
 161         } while (retval);
 162
 163         return IRQ_HANDLED;
 164 end:
 165         /* Stop TX here */
 166         lirc_rx51_off(lirc_rx51);
 167         lirc_rx51->wbuf_index = -1;
 168         omap_dm_timer_stop(lirc_rx51->pwm_timer);
 169         omap_dm_timer_stop(lirc_rx51->pulse_timer);
 170         omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0);
 171         wake_up_interruptible(&lirc_rx51->wqueue);
 172
 173         return IRQ_HANDLED;
 174 }
 175
 176 static int lirc_rx51_init_port(struct lirc_rx51 *lirc_rx51)
 177 {
 178         struct clk *clk_fclk;
 179         int retval, pwm_timer = lirc_rx51->pwm_timer_num;
 180
 181         lirc_rx51->pwm_timer = omap_dm_timer_request_specific(pwm_timer);
 182         if (lirc_rx51->pwm_timer == NULL) {
 183                 dev_err(lirc_rx51->dev, ": Error requesting GPT%d timer\n",
 184                         pwm_timer);
 185                 return -EBUSY;
 186         }
 187
 188         lirc_rx51->pulse_timer = omap_dm_timer_request();
 189         if (lirc_rx51->pulse_timer == NULL) {
 190                 dev_err(lirc_rx51->dev, ": Error requesting pulse timer\n");
 191                 retval = -EBUSY;
 192                 goto err1;
 193         }
 194
 195         omap_dm_timer_set_source(lirc_rx51->pwm_timer, OMAP_TIMER_SRC_SYS_CLK);
 196         omap_dm_timer_set_source(lirc_rx51->pulse_timer,
 197                                 OMAP_TIMER_SRC_SYS_CLK);
 198
 199         omap_dm_timer_enable(lirc_rx51->pwm_timer);
 200         omap_dm_timer_enable(lirc_rx51->pulse_timer);
 201
 202         lirc_rx51->irq_num = omap_dm_timer_get_irq(lirc_rx51->pulse_timer);
 203         retval = request_irq(lirc_rx51->irq_num, lirc_rx51_interrupt_handler,
 204                              IRQF_DISABLED | IRQF_SHARED,
 205                              "lirc_pulse_timer", lirc_rx51);
 206         if (retval) {
 207                 dev_err(lirc_rx51->dev, ": Failed to request interrupt line\n");
 208                 goto err2;
 209         }
 210
 211         clk_fclk = omap_dm_timer_get_fclk(lirc_rx51->pwm_timer);
 212         lirc_rx51->fclk_khz = clk_fclk->rate / 1000;
 213
 214         return 0;
 215
 216 err2:
 217         omap_dm_timer_free(lirc_rx51->pulse_timer);
 218 err1:
 219         omap_dm_timer_free(lirc_rx51->pwm_timer);
 220
 221         return retval;
 222 }
 223
 224 static int lirc_rx51_free_port(struct lirc_rx51 *lirc_rx51)
 225 {
 226         omap_dm_timer_set_int_enable(lirc_rx51->pulse_timer, 0);
 227         free_irq(lirc_rx51->irq_num, lirc_rx51);
 228         lirc_rx51_off(lirc_rx51);
 229         omap_dm_timer_disable(lirc_rx51->pwm_timer);
 230         omap_dm_timer_disable(lirc_rx51->pulse_timer);
 231         omap_dm_timer_free(lirc_rx51->pwm_timer);
 232         omap_dm_timer_free(lirc_rx51->pulse_timer);
 233         lirc_rx51->wbuf_index = -1;
 234
 235         return 0;
 236 }
 237
 238 static ssize_t lirc_rx51_write(struct file *file, const char *buf,
 239                           size_t n, loff_t *ppos)
 240 {
 241         int count, i;
 242         struct lirc_rx51 *lirc_rx51 = file->private_data;
 243
 244         if (n % sizeof(int))
 245                 return -EINVAL;
 246
 247         count = n / sizeof(int);
 248         if ((count > WBUF_LEN) || (count % 2 == 0))
 249                 return -EINVAL;
 250
 251         /* Wait any pending transfers to finish */
 252         wait_event_interruptible(lirc_rx51->wqueue, lirc_rx51->wbuf_index < 0);
 253
 254         if (copy_from_user(lirc_rx51->wbuf, buf, n))
 255                 return -EFAULT;
 256
 257         /* Sanity check the input pulses */
 258         for (i = 0; i < count; i++)
 259                 if (lirc_rx51->wbuf[i] < 0)
 260                         return -EINVAL;
 261
 262         init_timing_params(lirc_rx51);
 263         if (count < WBUF_LEN)
 264                 lirc_rx51->wbuf[count] = -1; /* Insert termination mark */
 265
 266         /*
 267          * Adjust latency requirements so the device doesn't go in too
 268          * deep sleep states
 269          */
 270         lirc_rx51->pdata->set_max_mpu_wakeup_lat(lirc_rx51->dev, 50);
 271
 272         lirc_rx51_on(lirc_rx51);
 273         lirc_rx51->wbuf_index = 1;
 274         pulse_timer_set_timeout(lirc_rx51, lirc_rx51->wbuf[0]);
 275
 276         /*
 277          * Don't return back to the userspace until the transfer has
 278          * finished
 279          */
 280         wait_event_interruptible(lirc_rx51->wqueue, lirc_rx51->wbuf_index < 0);
 281
 282         /* We can sleep again */
 283         lirc_rx51->pdata->set_max_mpu_wakeup_lat(lirc_rx51->dev, -1);
 284
 285         return n;
 286 }
 287
 288 static long lirc_rx51_ioctl(struct file *filep,
 289                         unsigned int cmd, unsigned long arg)
 290 {
 291         int result;
 292         unsigned long value;
 293         unsigned int ivalue;
 294         struct lirc_rx51 *lirc_rx51 = filep->private_data;
 295
 296         switch (cmd) {
 297         case LIRC_GET_SEND_MODE:
 298                 result = put_user(LIRC_MODE_PULSE, (unsigned long *)arg);
 299                 if (result)
 300                         return result;
 301                 break;
 302
 303         case LIRC_SET_SEND_MODE:
 304                 result = get_user(value, (unsigned long *)arg);
 305                 if (result)
 306                         return result;
 307
 308                 /* only LIRC_MODE_PULSE supported */
 309                 if (value != LIRC_MODE_PULSE)
 310                         return -ENOSYS;
 311                 break;
 312
 313         case LIRC_GET_REC_MODE:
 314                 result = put_user(0, (unsigned long *) arg);
 315                 if (result)
 316                         return result;
 317                 break;
 318
 319         case LIRC_GET_LENGTH:
 320                 return -ENOSYS;
 321                 break;
 322
 323         case LIRC_SET_SEND_DUTY_CYCLE:
 324                 result = get_user(ivalue, (unsigned int *) arg);
 325                 if (result)
 326                         return result;
 327
 328                 if (ivalue <= 0 || ivalue > 100) {
 329                         dev_err(lirc_rx51->dev, ": invalid duty cycle %d\n",
 330                                 ivalue);
 331                         return -EINVAL;
 332                 }
 333
 334                 lirc_rx51->duty_cycle = ivalue;
 335                 break;
 336
 337         case LIRC_SET_SEND_CARRIER:
 338                 result = get_user(ivalue, (unsigned int *) arg);
 339                 if (result)
 340                         return result;
 341
 342                 if (ivalue > 500000 || ivalue < 20000) {
 343                         dev_err(lirc_rx51->dev, ": invalid carrier freq %d\n",
 344                                 ivalue);
 345                         return -EINVAL;
 346                 }
 347
 348                 lirc_rx51->freq = ivalue;
 349                 break;
 350
 351         case LIRC_GET_FEATURES:
 352                 result = put_user(LIRC_RX51_DRIVER_FEATURES,
 353                                   (unsigned long *) arg);
 354                 if (result)
 355                         return result;
 356                 break;
 357
 358         default:
 359                 return -ENOIOCTLCMD;
 360         }
 361
 362         return 0;
 363 }
 364
 365 static int lirc_rx51_open(struct inode *inode, struct file *file)
 366 {
 367         struct lirc_rx51 *lirc_rx51 = lirc_get_pdata(file);
 368         BUG_ON(!lirc_rx51);
 369
 370         file->private_data = lirc_rx51;
 371
 372         if (test_and_set_bit(1, &lirc_rx51->device_is_open))
 373                 return -EBUSY;
 374
 375         return lirc_rx51_init_port(lirc_rx51);
 376 }
 377
 378 static int lirc_rx51_release(struct inode *inode, struct file *file)
 379 {
 380         struct lirc_rx51 *lirc_rx51 = file->private_data;
 381
 382         lirc_rx51_free_port(lirc_rx51);
 383
 384         clear_bit(1, &lirc_rx51->device_is_open);
 385
 386         return 0;
 387 }
 388
 389 static struct lirc_rx51 lirc_rx51 = {
 390         .freq           = 38000,
 391         .duty_cycle     = 50,
 392         .wbuf_index     = -1,
 393 };
 394
 395 static const struct file_operations lirc_fops = {
 396         .owner          = THIS_MODULE,
 397         .write          = lirc_rx51_write,
 398         .unlocked_ioctl = lirc_rx51_ioctl,
 399         .read           = lirc_dev_fop_read,
 400         .poll           = lirc_dev_fop_poll,
 401         .open           = lirc_rx51_open,
 402         .release        = lirc_rx51_release,
 403 };
 404
 405 static struct lirc_driver lirc_rx51_driver = {
 406         .name           = DRIVER_NAME,
 407         .minor          = -1,
 408         .code_length    = 1,
 409         .data           = &lirc_rx51,
 410         .fops           = &lirc_fops,
 411         .owner          = THIS_MODULE,
 412 };
 413
 414 #ifdef CONFIG_PM
 415
 416 static int lirc_rx51_suspend(struct platform_device *dev, pm_message_t state)
 417 {
 418         /*
 419          * In case the device is still open, do not suspend. Normally
 420          * this should not be a problem as lircd only keeps the device
 421          * open only for short periods of time. We also don't want to
 422          * get involved with race conditions that might happen if we
 423          * were in a middle of a transmit. Thus, we defer any suspend
 424          * actions until transmit has completed.
 425          */
 426         if (test_and_set_bit(1, &lirc_rx51.device_is_open))
 427                 return -EAGAIN;
 428
 429         clear_bit(1, &lirc_rx51.device_is_open);
 430
 431         return 0;
 432 }
 433
 434 static int lirc_rx51_resume(struct platform_device *dev)
 435 {
 436         return 0;
 437 }
 438
 439 #else
 440
 441 #define lirc_rx51_suspend       NULL
 442 #define lirc_rx51_resume        NULL
 443
 444 #endif /* CONFIG_PM */
 445
 446 static int lirc_rx51_probe(struct platform_device *dev)
 447 {
 448         lirc_rx51_driver.features = LIRC_RX51_DRIVER_FEATURES;
 449         lirc_rx51.pdata = dev->dev.platform_data;
 450         lirc_rx51.pwm_timer_num = lirc_rx51.pdata->pwm_timer;
 451         lirc_rx51.dev = &dev->dev;
 452         lirc_rx51_driver.dev = &dev->dev;
 453         lirc_rx51_driver.minor = lirc_register_driver(&lirc_rx51_driver);
 454         init_waitqueue_head(&lirc_rx51.wqueue);
 455
 456         if (lirc_rx51_driver.minor < 0) {
 457                 dev_err(lirc_rx51.dev, ": lirc_register_driver failed: %d\n",
 458                        lirc_rx51_driver.minor);
 459                 return lirc_rx51_driver.minor;
 460         }
 461         dev_info(lirc_rx51.dev, "registration ok, minor: %d, pwm: %d\n",
 462                  lirc_rx51_driver.minor, lirc_rx51.pwm_timer_num);
 463
 464         return 0;
 465 }
 466
 467 static int lirc_rx51_remove(struct platform_device *dev)
 468 {
 469         return lirc_unregister_driver(lirc_rx51_driver.minor);
 470 }
 471
 472 struct platform_driver lirc_rx51_platform_driver = {
 473         .probe          = lirc_rx51_probe,
 474         .remove         = lirc_rx51_remove,
 475         .suspend        = lirc_rx51_suspend,
 476         .resume         = lirc_rx51_resume,
 477         .driver         = {
 478                 .name   = DRIVER_NAME,
 479                 .owner  = THIS_MODULE,
 480         },
 481 };
 482 module_platform_driver(lirc_rx51_platform_driver);
 483
 484 MODULE_DESCRIPTION("LIRC TX driver for Nokia RX51");
 485 MODULE_AUTHOR("Nokia Corporation");
 486 MODULE_LICENSE("GPL");