drivers/media/rc/ttusbir.c

   1 /*
   2  * TechnoTrend USB IR Receiver
   3  *
   4  * Copyright (C) 2012 Sean Young <sean@mess.org>
   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
  17 #include <linux/module.h>
  18 #include <linux/usb.h>
  19 #include <linux/usb/input.h>
  20 #include <linux/slab.h>
  21 #include <linux/leds.h>
  22 #include <media/rc-core.h>
  23
  24 #define DRIVER_NAME     "ttusbir"
  25 #define DRIVER_DESC     "TechnoTrend USB IR Receiver"
  26 /*
  27  * The Windows driver uses 8 URBS, the original lirc drivers has a
  28  * configurable amount (2 default, 4 max). This device generates about 125
  29  * messages per second (!), whether IR is idle or not.
  30  */
  31 #define NUM_URBS        4
  32 #define NS_PER_BYTE     62500
  33 #define NS_PER_BIT      (NS_PER_BYTE/8)
  34
  35 struct ttusbir {
  36         struct rc_dev *rc;
  37         struct device *dev;
  38         struct usb_device *udev;
  39
  40         struct urb *urb[NUM_URBS];
  41
  42         struct led_classdev led;
  43         struct urb *bulk_urb;
  44         uint8_t bulk_buffer[5];
  45         int bulk_out_endp, iso_in_endp;
  46         bool led_on, is_led_on;
  47         atomic_t led_complete;
  48
  49         char phys[64];
  50 };
  51
  52 static enum led_brightness ttusbir_brightness_get(struct led_classdev *led_dev)
  53 {
  54         struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
  55
  56         return tt->led_on ? LED_FULL : LED_OFF;
  57 }
  58
  59 static void ttusbir_set_led(struct ttusbir *tt)
  60 {
  61         int ret;
  62
  63         smp_mb();
  64
  65         if (tt->led_on != tt->is_led_on && tt->udev &&
  66                                 atomic_add_unless(&tt->led_complete, 1, 1)) {
  67                 tt->bulk_buffer[4] = tt->is_led_on = tt->led_on;
  68                 ret = usb_submit_urb(tt->bulk_urb, GFP_ATOMIC);
  69                 if (ret) {
  70                         dev_warn(tt->dev, "failed to submit bulk urb: %d\n",
  71                                                                         ret);
  72                         atomic_dec(&tt->led_complete);
  73                 }
  74         }
  75 }
  76
  77 static void ttusbir_brightness_set(struct led_classdev *led_dev, enum
  78                                                 led_brightness brightness)
  79 {
  80         struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
  81
  82         tt->led_on = brightness != LED_OFF;
  83
  84         ttusbir_set_led(tt);
  85 }
  86
  87 /*
  88  * The urb cannot be reused until the urb completes
  89  */
  90 static void ttusbir_bulk_complete(struct urb *urb)
  91 {
  92         struct ttusbir *tt = urb->context;
  93
  94         atomic_dec(&tt->led_complete);
  95
  96         switch (urb->status) {
  97         case 0:
  98                 break;
  99         case -ECONNRESET:
 100         case -ENOENT:
 101         case -ESHUTDOWN:
 102                 usb_unlink_urb(urb);
 103                 return;
 104         case -EPIPE:
 105         default:
 106                 dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
 107                 break;
 108         }
 109
 110         ttusbir_set_led(tt);
 111 }
 112
 113 /*
 114  * The data is one bit per sample, a set bit signifying silence and samples
 115  * being MSB first. Bit 0 can contain garbage so take it to be whatever
 116  * bit 1 is, so we don't have unexpected edges.
 117  */
 118 static void ttusbir_process_ir_data(struct ttusbir *tt, uint8_t *buf)
 119 {
 120         struct ir_raw_event rawir = {};
 121         unsigned i, v, b;
 122         bool event = false;
 123
 124         for (i = 0; i < 128; i++) {
 125                 v = buf[i] & 0xfe;
 126                 switch (v) {
 127                 case 0xfe:
 128                         rawir.pulse = false;
 129                         rawir.duration = NS_PER_BYTE;
 130                         if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 131                                 event = true;
 132                         break;
 133                 case 0:
 134                         rawir.pulse = true;
 135                         rawir.duration = NS_PER_BYTE;
 136                         if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 137                                 event = true;
 138                         break;
 139                 default:
 140                         /* one edge per byte */
 141                         if (v & 2) {
 142                                 b = ffz(v | 1);
 143                                 rawir.pulse = true;
 144                         } else {
 145                                 b = ffs(v) - 1;
 146                                 rawir.pulse = false;
 147                         }
 148
 149                         rawir.duration = NS_PER_BIT * (8 - b);
 150                         if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 151                                 event = true;
 152
 153                         rawir.pulse = !rawir.pulse;
 154                         rawir.duration = NS_PER_BIT * b;
 155                         if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 156                                 event = true;
 157                         break;
 158                 }
 159         }
 160
 161         /* don't wakeup when there's nothing to do */
 162         if (event)
 163                 ir_raw_event_handle(tt->rc);
 164 }
 165
 166 static void ttusbir_urb_complete(struct urb *urb)
 167 {
 168         struct ttusbir *tt = urb->context;
 169         int rc;
 170
 171         switch (urb->status) {
 172         case 0:
 173                 ttusbir_process_ir_data(tt, urb->transfer_buffer);
 174                 break;
 175         case -ECONNRESET:
 176         case -ENOENT:
 177         case -ESHUTDOWN:
 178                 usb_unlink_urb(urb);
 179                 return;
 180         case -EPIPE:
 181         default:
 182                 dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
 183                 break;
 184         }
 185
 186         rc = usb_submit_urb(urb, GFP_ATOMIC);
 187         if (rc && rc != -ENODEV)
 188                 dev_warn(tt->dev, "failed to resubmit urb: %d\n", rc);
 189 }
 190
 191 static int ttusbir_probe(struct usb_interface *intf,
 192                          const struct usb_device_id *id)
 193 {
 194         struct ttusbir *tt;
 195         struct usb_interface_descriptor *idesc;
 196         struct usb_endpoint_descriptor *desc;
 197         struct rc_dev *rc;
 198         int i, j, ret;
 199         int altsetting = -1;
 200
 201         tt = kzalloc(sizeof(*tt), GFP_KERNEL);
 202         rc = rc_allocate_device(RC_DRIVER_IR_RAW);
 203         if (!tt || !rc) {
 204                 ret = -ENOMEM;
 205                 goto out;
 206         }
 207
 208         /* find the correct alt setting */
 209         for (i = 0; i < intf->num_altsetting && altsetting == -1; i++) {
 210                 int max_packet, bulk_out_endp = -1, iso_in_endp = -1;
 211
 212                 idesc = &intf->altsetting[i].desc;
 213
 214                 for (j = 0; j < idesc->bNumEndpoints; j++) {
 215                         desc = &intf->altsetting[i].endpoint[j].desc;
 216                         max_packet = le16_to_cpu(desc->wMaxPacketSize);
 217                         if (usb_endpoint_dir_in(desc) &&
 218                                         usb_endpoint_xfer_isoc(desc) &&
 219                                         max_packet == 0x10)
 220                                 iso_in_endp = j;
 221                         else if (usb_endpoint_dir_out(desc) &&
 222                                         usb_endpoint_xfer_bulk(desc) &&
 223                                         max_packet == 0x20)
 224                                 bulk_out_endp = j;
 225
 226                         if (bulk_out_endp != -1 && iso_in_endp != -1) {
 227                                 tt->bulk_out_endp = bulk_out_endp;
 228                                 tt->iso_in_endp = iso_in_endp;
 229                                 altsetting = i;
 230                                 break;
 231                         }
 232                 }
 233         }
 234
 235         if (altsetting == -1) {
 236                 dev_err(&intf->dev, "cannot find expected altsetting\n");
 237                 ret = -ENODEV;
 238                 goto out;
 239         }
 240
 241         tt->dev = &intf->dev;
 242         tt->udev = interface_to_usbdev(intf);
 243         tt->rc = rc;
 244
 245         ret = usb_set_interface(tt->udev, 0, altsetting);
 246         if (ret)
 247                 goto out;
 248
 249         for (i = 0; i < NUM_URBS; i++) {
 250                 struct urb *urb = usb_alloc_urb(8, GFP_KERNEL);
 251                 void *buffer;
 252
 253                 if (!urb) {
 254                         ret = -ENOMEM;
 255                         goto out;
 256                 }
 257
 258                 urb->dev = tt->udev;
 259                 urb->context = tt;
 260                 urb->pipe = usb_rcvisocpipe(tt->udev, tt->iso_in_endp);
 261                 urb->interval = 1;
 262                 buffer = usb_alloc_coherent(tt->udev, 128, GFP_KERNEL,
 263                                                 &urb->transfer_dma);
 264                 if (!buffer) {
 265                         usb_free_urb(urb);
 266                         ret = -ENOMEM;
 267                         goto out;
 268                 }
 269                 urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP | URB_ISO_ASAP;
 270                 urb->transfer_buffer = buffer;
 271                 urb->complete = ttusbir_urb_complete;
 272                 urb->number_of_packets = 8;
 273                 urb->transfer_buffer_length = 128;
 274
 275                 for (j = 0; j < 8; j++) {
 276                         urb->iso_frame_desc[j].offset = j * 16;
 277                         urb->iso_frame_desc[j].length = 16;
 278                 }
 279
 280                 tt->urb[i] = urb;
 281         }
 282
 283         tt->bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
 284         if (!tt->bulk_urb) {
 285                 ret = -ENOMEM;
 286                 goto out;
 287         }
 288
 289         tt->bulk_buffer[0] = 0xaa;
 290         tt->bulk_buffer[1] = 0x01;
 291         tt->bulk_buffer[2] = 0x05;
 292         tt->bulk_buffer[3] = 0x01;
 293
 294         usb_fill_bulk_urb(tt->bulk_urb, tt->udev, usb_sndbulkpipe(tt->udev,
 295                 tt->bulk_out_endp), tt->bulk_buffer, sizeof(tt->bulk_buffer),
 296                                                 ttusbir_bulk_complete, tt);
 297
 298         tt->led.name = "ttusbir:green:power";
 299         tt->led.default_trigger = "rc-feedback";
 300         tt->led.brightness_set = ttusbir_brightness_set;
 301         tt->led.brightness_get = ttusbir_brightness_get;
 302         tt->is_led_on = tt->led_on = true;
 303         atomic_set(&tt->led_complete, 0);
 304         ret = led_classdev_register(&intf->dev, &tt->led);
 305         if (ret)
 306                 goto out;
 307
 308         usb_make_path(tt->udev, tt->phys, sizeof(tt->phys));
 309
 310         rc->device_name = DRIVER_DESC;
 311         rc->input_phys = tt->phys;
 312         usb_to_input_id(tt->udev, &rc->input_id);
 313         rc->dev.parent = &intf->dev;
 314         rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
 315         rc->priv = tt;
 316         rc->driver_name = DRIVER_NAME;
 317         rc->map_name = RC_MAP_TT_1500;
 318         rc->min_timeout = 1;
 319         rc->timeout = IR_DEFAULT_TIMEOUT;
 320         rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
 321
 322         /*
 323          * The precision is NS_PER_BIT, but since every 8th bit can be
 324          * overwritten with garbage the accuracy is at best 2 * NS_PER_BIT.
 325          */
 326         rc->rx_resolution = NS_PER_BIT;
 327
 328         ret = rc_register_device(rc);
 329         if (ret) {
 330                 dev_err(&intf->dev, "failed to register rc device %d\n", ret);
 331                 goto out2;
 332         }
 333
 334         usb_set_intfdata(intf, tt);
 335
 336         for (i = 0; i < NUM_URBS; i++) {
 337                 ret = usb_submit_urb(tt->urb[i], GFP_KERNEL);
 338                 if (ret) {
 339                         dev_err(tt->dev, "failed to submit urb %d\n", ret);
 340                         goto out3;
 341                 }
 342         }
 343
 344         return 0;
 345 out3:
 346         rc_unregister_device(rc);
 347         rc = NULL;
 348 out2:
 349         led_classdev_unregister(&tt->led);
 350 out:
 351         if (tt) {
 352                 for (i = 0; i < NUM_URBS && tt->urb[i]; i++) {
 353                         struct urb *urb = tt->urb[i];
 354
 355                         usb_kill_urb(urb);
 356                         usb_free_coherent(tt->udev, 128, urb->transfer_buffer,
 357                                                         urb->transfer_dma);
 358                         usb_free_urb(urb);
 359                 }
 360                 usb_kill_urb(tt->bulk_urb);
 361                 usb_free_urb(tt->bulk_urb);
 362                 kfree(tt);
 363         }
 364         rc_free_device(rc);
 365
 366         return ret;
 367 }
 368
 369 static void ttusbir_disconnect(struct usb_interface *intf)
 370 {
 371         struct ttusbir *tt = usb_get_intfdata(intf);
 372         struct usb_device *udev = tt->udev;
 373         int i;
 374
 375         tt->udev = NULL;
 376
 377         rc_unregister_device(tt->rc);
 378         led_classdev_unregister(&tt->led);
 379         for (i = 0; i < NUM_URBS; i++) {
 380                 usb_kill_urb(tt->urb[i]);
 381                 usb_free_coherent(udev, 128, tt->urb[i]->transfer_buffer,
 382                                                 tt->urb[i]->transfer_dma);
 383                 usb_free_urb(tt->urb[i]);
 384         }
 385         usb_kill_urb(tt->bulk_urb);
 386         usb_free_urb(tt->bulk_urb);
 387         usb_set_intfdata(intf, NULL);
 388         kfree(tt);
 389 }
 390
 391 static int ttusbir_suspend(struct usb_interface *intf, pm_message_t message)
 392 {
 393         struct ttusbir *tt = usb_get_intfdata(intf);
 394         int i;
 395
 396         for (i = 0; i < NUM_URBS; i++)
 397                 usb_kill_urb(tt->urb[i]);
 398
 399         led_classdev_suspend(&tt->led);
 400         usb_kill_urb(tt->bulk_urb);
 401
 402         return 0;
 403 }
 404
 405 static int ttusbir_resume(struct usb_interface *intf)
 406 {
 407         struct ttusbir *tt = usb_get_intfdata(intf);
 408         int i, rc;
 409
 410         tt->is_led_on = true;
 411         led_classdev_resume(&tt->led);
 412
 413         for (i = 0; i < NUM_URBS; i++) {
 414                 rc = usb_submit_urb(tt->urb[i], GFP_KERNEL);
 415                 if (rc) {
 416                         dev_warn(tt->dev, "failed to submit urb: %d\n", rc);
 417                         break;
 418                 }
 419         }
 420
 421         return rc;
 422 }
 423
 424 static const struct usb_device_id ttusbir_table[] = {
 425         { USB_DEVICE(0x0b48, 0x2003) },
 426         { }
 427 };
 428
 429 static struct usb_driver ttusbir_driver = {
 430         .name = DRIVER_NAME,
 431         .id_table = ttusbir_table,
 432         .probe = ttusbir_probe,
 433         .suspend = ttusbir_suspend,
 434         .resume = ttusbir_resume,
 435         .reset_resume = ttusbir_resume,
 436         .disconnect = ttusbir_disconnect,
 437 };
 438
 439 module_usb_driver(ttusbir_driver);
 440
 441 MODULE_DESCRIPTION(DRIVER_DESC);
 442 MODULE_AUTHOR("Sean Young <sean@mess.org>");
 443 MODULE_LICENSE("GPL");
 444 MODULE_DEVICE_TABLE(usb, ttusbir_table);
 445