drivers/media/rc/ttusbir.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * TechnoTrend USB IR Receiver
   4  *
   5  * Copyright (C) 2012 Sean Young <sean@mess.org>
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/usb.h>
  10 #include <linux/usb/input.h>
  11 #include <linux/slab.h>
  12 #include <linux/leds.h>
  13 #include <media/rc-core.h>
  14
  15 #define DRIVER_NAME     "ttusbir"
  16 #define DRIVER_DESC     "TechnoTrend USB IR Receiver"
  17 /*
  18  * The Windows driver uses 8 URBS, the original lirc drivers has a
  19  * configurable amount (2 default, 4 max). This device generates about 125
  20  * messages per second (!), whether IR is idle or not.
  21  */
  22 #define NUM_URBS        4
  23 #define US_PER_BYTE     62
  24 #define US_PER_BIT      (US_PER_BYTE / 8)
  25
  26 struct ttusbir {
  27         struct rc_dev *rc;
  28         struct device *dev;
  29         struct usb_device *udev;
  30
  31         struct urb *urb[NUM_URBS];
  32
  33         struct led_classdev led;
  34         struct urb *bulk_urb;
  35         uint8_t bulk_buffer[5];
  36         int bulk_out_endp, iso_in_endp;
  37         bool led_on, is_led_on;
  38         atomic_t led_complete;
  39
  40         char phys[64];
  41 };
  42
  43 static enum led_brightness ttusbir_brightness_get(struct led_classdev *led_dev)
  44 {
  45         struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
  46
  47         return tt->led_on ? LED_FULL : LED_OFF;
  48 }
  49
  50 static void ttusbir_set_led(struct ttusbir *tt)
  51 {
  52         int ret;
  53
  54         smp_mb();
  55
  56         if (tt->led_on != tt->is_led_on && tt->udev &&
  57                                 atomic_add_unless(&tt->led_complete, 1, 1)) {
  58                 tt->bulk_buffer[4] = tt->is_led_on = tt->led_on;
  59                 ret = usb_submit_urb(tt->bulk_urb, GFP_ATOMIC);
  60                 if (ret) {
  61                         dev_warn(tt->dev, "failed to submit bulk urb: %d\n",
  62                                                                         ret);
  63                         atomic_dec(&tt->led_complete);
  64                 }
  65         }
  66 }
  67
  68 static void ttusbir_brightness_set(struct led_classdev *led_dev, enum
  69                                                 led_brightness brightness)
  70 {
  71         struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
  72
  73         tt->led_on = brightness != LED_OFF;
  74
  75         ttusbir_set_led(tt);
  76 }
  77
  78 /*
  79  * The urb cannot be reused until the urb completes
  80  */
  81 static void ttusbir_bulk_complete(struct urb *urb)
  82 {
  83         struct ttusbir *tt = urb->context;
  84
  85         atomic_dec(&tt->led_complete);
  86
  87         switch (urb->status) {
  88         case 0:
  89                 break;
  90         case -ECONNRESET:
  91         case -ENOENT:
  92         case -ESHUTDOWN:
  93                 return;
  94         case -EPIPE:
  95         default:
  96                 dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
  97                 break;
  98         }
  99
 100         ttusbir_set_led(tt);
 101 }
 102
 103 /*
 104  * The data is one bit per sample, a set bit signifying silence and samples
 105  * being MSB first. Bit 0 can contain garbage so take it to be whatever
 106  * bit 1 is, so we don't have unexpected edges.
 107  */
 108 static void ttusbir_process_ir_data(struct ttusbir *tt, uint8_t *buf)
 109 {
 110         struct ir_raw_event rawir = {};
 111         unsigned i, v, b;
 112         bool event = false;
 113
 114         for (i = 0; i < 128; i++) {
 115                 v = buf[i] & 0xfe;
 116                 switch (v) {
 117                 case 0xfe:
 118                         rawir.pulse = false;
 119                         rawir.duration = US_PER_BYTE;
 120                         if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 121                                 event = true;
 122                         break;
 123                 case 0:
 124                         rawir.pulse = true;
 125                         rawir.duration = US_PER_BYTE;
 126                         if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 127                                 event = true;
 128                         break;
 129                 default:
 130                         /* one edge per byte */
 131                         if (v & 2) {
 132                                 b = ffz(v | 1);
 133                                 rawir.pulse = true;
 134                         } else {
 135                                 b = ffs(v) - 1;
 136                                 rawir.pulse = false;
 137                         }
 138
 139                         rawir.duration = US_PER_BIT * (8 - b);
 140                         if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 141                                 event = true;
 142
 143                         rawir.pulse = !rawir.pulse;
 144                         rawir.duration = US_PER_BIT * b;
 145                         if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 146                                 event = true;
 147                         break;
 148                 }
 149         }
 150
 151         /* don't wakeup when there's nothing to do */
 152         if (event)
 153                 ir_raw_event_handle(tt->rc);
 154 }
 155
 156 static void ttusbir_urb_complete(struct urb *urb)
 157 {
 158         struct ttusbir *tt = urb->context;
 159         int rc;
 160
 161         switch (urb->status) {
 162         case 0:
 163                 ttusbir_process_ir_data(tt, urb->transfer_buffer);
 164                 break;
 165         case -ECONNRESET:
 166         case -ENOENT:
 167         case -ESHUTDOWN:
 168                 return;
 169         case -EPIPE:
 170         default:
 171                 dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
 172                 break;
 173         }
 174
 175         rc = usb_submit_urb(urb, GFP_ATOMIC);
 176         if (rc && rc != -ENODEV)
 177                 dev_warn(tt->dev, "failed to resubmit urb: %d\n", rc);
 178 }
 179
 180 static int ttusbir_probe(struct usb_interface *intf,
 181                          const struct usb_device_id *id)
 182 {
 183         struct ttusbir *tt;
 184         struct usb_interface_descriptor *idesc;
 185         struct usb_endpoint_descriptor *desc;
 186         struct rc_dev *rc;
 187         int i, j, ret;
 188         int altsetting = -1;
 189
 190         tt = kzalloc(sizeof(*tt), GFP_KERNEL);
 191         rc = rc_allocate_device(RC_DRIVER_IR_RAW);
 192         if (!tt || !rc) {
 193                 ret = -ENOMEM;
 194                 goto out;
 195         }
 196
 197         /* find the correct alt setting */
 198         for (i = 0; i < intf->num_altsetting && altsetting == -1; i++) {
 199                 int max_packet, bulk_out_endp = -1, iso_in_endp = -1;
 200
 201                 idesc = &intf->altsetting[i].desc;
 202
 203                 for (j = 0; j < idesc->bNumEndpoints; j++) {
 204                         desc = &intf->altsetting[i].endpoint[j].desc;
 205                         max_packet = le16_to_cpu(desc->wMaxPacketSize);
 206                         if (usb_endpoint_dir_in(desc) &&
 207                                         usb_endpoint_xfer_isoc(desc) &&
 208                                         max_packet == 0x10)
 209                                 iso_in_endp = j;
 210                         else if (usb_endpoint_dir_out(desc) &&
 211                                         usb_endpoint_xfer_bulk(desc) &&
 212                                         max_packet == 0x20)
 213                                 bulk_out_endp = j;
 214
 215                         if (bulk_out_endp != -1 && iso_in_endp != -1) {
 216                                 tt->bulk_out_endp = bulk_out_endp;
 217                                 tt->iso_in_endp = iso_in_endp;
 218                                 altsetting = i;
 219                                 break;
 220                         }
 221                 }
 222         }
 223
 224         if (altsetting == -1) {
 225                 dev_err(&intf->dev, "cannot find expected altsetting\n");
 226                 ret = -ENODEV;
 227                 goto out;
 228         }
 229
 230         tt->dev = &intf->dev;
 231         tt->udev = interface_to_usbdev(intf);
 232         tt->rc = rc;
 233
 234         ret = usb_set_interface(tt->udev, 0, altsetting);
 235         if (ret)
 236                 goto out;
 237
 238         for (i = 0; i < NUM_URBS; i++) {
 239                 struct urb *urb = usb_alloc_urb(8, GFP_KERNEL);
 240                 void *buffer;
 241
 242                 if (!urb) {
 243                         ret = -ENOMEM;
 244                         goto out;
 245                 }
 246
 247                 urb->dev = tt->udev;
 248                 urb->context = tt;
 249                 urb->pipe = usb_rcvisocpipe(tt->udev, tt->iso_in_endp);
 250                 urb->interval = 1;
 251                 buffer = usb_alloc_coherent(tt->udev, 128, GFP_KERNEL,
 252                                                 &urb->transfer_dma);
 253                 if (!buffer) {
 254                         usb_free_urb(urb);
 255                         ret = -ENOMEM;
 256                         goto out;
 257                 }
 258                 urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP | URB_ISO_ASAP;
 259                 urb->transfer_buffer = buffer;
 260                 urb->complete = ttusbir_urb_complete;
 261                 urb->number_of_packets = 8;
 262                 urb->transfer_buffer_length = 128;
 263
 264                 for (j = 0; j < 8; j++) {
 265                         urb->iso_frame_desc[j].offset = j * 16;
 266                         urb->iso_frame_desc[j].length = 16;
 267                 }
 268
 269                 tt->urb[i] = urb;
 270         }
 271
 272         tt->bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
 273         if (!tt->bulk_urb) {
 274                 ret = -ENOMEM;
 275                 goto out;
 276         }
 277
 278         tt->bulk_buffer[0] = 0xaa;
 279         tt->bulk_buffer[1] = 0x01;
 280         tt->bulk_buffer[2] = 0x05;
 281         tt->bulk_buffer[3] = 0x01;
 282
 283         usb_fill_bulk_urb(tt->bulk_urb, tt->udev, usb_sndbulkpipe(tt->udev,
 284                 tt->bulk_out_endp), tt->bulk_buffer, sizeof(tt->bulk_buffer),
 285                                                 ttusbir_bulk_complete, tt);
 286
 287         tt->led.name = "ttusbir:green:power";
 288         tt->led.default_trigger = "rc-feedback";
 289         tt->led.brightness_set = ttusbir_brightness_set;
 290         tt->led.brightness_get = ttusbir_brightness_get;
 291         tt->is_led_on = tt->led_on = true;
 292         atomic_set(&tt->led_complete, 0);
 293         ret = led_classdev_register(&intf->dev, &tt->led);
 294         if (ret)
 295                 goto out;
 296
 297         usb_make_path(tt->udev, tt->phys, sizeof(tt->phys));
 298
 299         rc->device_name = DRIVER_DESC;
 300         rc->input_phys = tt->phys;
 301         usb_to_input_id(tt->udev, &rc->input_id);
 302         rc->dev.parent = &intf->dev;
 303         rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
 304         rc->priv = tt;
 305         rc->driver_name = DRIVER_NAME;
 306         rc->map_name = RC_MAP_TT_1500;
 307         rc->min_timeout = 1;
 308         rc->timeout = IR_DEFAULT_TIMEOUT;
 309         rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
 310
 311         /*
 312          * The precision is US_PER_BIT, but since every 8th bit can be
 313          * overwritten with garbage the accuracy is at best 2 * US_PER_BIT.
 314          */
 315         rc->rx_resolution = 2 * US_PER_BIT;
 316
 317         ret = rc_register_device(rc);
 318         if (ret) {
 319                 dev_err(&intf->dev, "failed to register rc device %d\n", ret);
 320                 goto out2;
 321         }
 322
 323         usb_set_intfdata(intf, tt);
 324
 325         for (i = 0; i < NUM_URBS; i++) {
 326                 ret = usb_submit_urb(tt->urb[i], GFP_KERNEL);
 327                 if (ret) {
 328                         dev_err(tt->dev, "failed to submit urb %d\n", ret);
 329                         goto out3;
 330                 }
 331         }
 332
 333         return 0;
 334 out3:
 335         rc_unregister_device(rc);
 336         rc = NULL;
 337 out2:
 338         led_classdev_unregister(&tt->led);
 339 out:
 340         if (tt) {
 341                 for (i = 0; i < NUM_URBS && tt->urb[i]; i++) {
 342                         struct urb *urb = tt->urb[i];
 343
 344                         usb_kill_urb(urb);
 345                         usb_free_coherent(tt->udev, 128, urb->transfer_buffer,
 346                                                         urb->transfer_dma);
 347                         usb_free_urb(urb);
 348                 }
 349                 usb_kill_urb(tt->bulk_urb);
 350                 usb_free_urb(tt->bulk_urb);
 351                 kfree(tt);
 352         }
 353         rc_free_device(rc);
 354
 355         return ret;
 356 }
 357
 358 static void ttusbir_disconnect(struct usb_interface *intf)
 359 {
 360         struct ttusbir *tt = usb_get_intfdata(intf);
 361         struct usb_device *udev = tt->udev;
 362         int i;
 363
 364         tt->udev = NULL;
 365
 366         rc_unregister_device(tt->rc);
 367         led_classdev_unregister(&tt->led);
 368         for (i = 0; i < NUM_URBS; i++) {
 369                 usb_kill_urb(tt->urb[i]);
 370                 usb_free_coherent(udev, 128, tt->urb[i]->transfer_buffer,
 371                                                 tt->urb[i]->transfer_dma);
 372                 usb_free_urb(tt->urb[i]);
 373         }
 374         usb_kill_urb(tt->bulk_urb);
 375         usb_free_urb(tt->bulk_urb);
 376         usb_set_intfdata(intf, NULL);
 377         kfree(tt);
 378 }
 379
 380 static int ttusbir_suspend(struct usb_interface *intf, pm_message_t message)
 381 {
 382         struct ttusbir *tt = usb_get_intfdata(intf);
 383         int i;
 384
 385         for (i = 0; i < NUM_URBS; i++)
 386                 usb_kill_urb(tt->urb[i]);
 387
 388         led_classdev_suspend(&tt->led);
 389         usb_kill_urb(tt->bulk_urb);
 390
 391         return 0;
 392 }
 393
 394 static int ttusbir_resume(struct usb_interface *intf)
 395 {
 396         struct ttusbir *tt = usb_get_intfdata(intf);
 397         int i, rc;
 398
 399         tt->is_led_on = true;
 400         led_classdev_resume(&tt->led);
 401
 402         for (i = 0; i < NUM_URBS; i++) {
 403                 rc = usb_submit_urb(tt->urb[i], GFP_NOIO);
 404                 if (rc) {
 405                         dev_warn(tt->dev, "failed to submit urb: %d\n", rc);
 406                         break;
 407                 }
 408         }
 409
 410         return rc;
 411 }
 412
 413 static const struct usb_device_id ttusbir_table[] = {
 414         { USB_DEVICE(0x0b48, 0x2003) },
 415         { }
 416 };
 417
 418 static struct usb_driver ttusbir_driver = {
 419         .name = DRIVER_NAME,
 420         .id_table = ttusbir_table,
 421         .probe = ttusbir_probe,
 422         .suspend = ttusbir_suspend,
 423         .resume = ttusbir_resume,
 424         .reset_resume = ttusbir_resume,
 425         .disconnect = ttusbir_disconnect,
 426 };
 427
 428 module_usb_driver(ttusbir_driver);
 429
 430 MODULE_DESCRIPTION(DRIVER_DESC);
 431 MODULE_AUTHOR("Sean Young <sean@mess.org>");
 432 MODULE_LICENSE("GPL");
 433 MODULE_DEVICE_TABLE(usb, ttusbir_table);
 434