linux/drivers/media/rc/ttusbir.c
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   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
  35struct 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
  52static 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
  59static 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
  77static 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 */
  90static 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 */
 118static 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        init_ir_raw_event(&rawir);
 125
 126        for (i = 0; i < 128; i++) {
 127                v = buf[i] & 0xfe;
 128                switch (v) {
 129                case 0xfe:
 130                        rawir.pulse = false;
 131                        rawir.duration = NS_PER_BYTE;
 132                        if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 133                                event = true;
 134                        break;
 135                case 0:
 136                        rawir.pulse = true;
 137                        rawir.duration = NS_PER_BYTE;
 138                        if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 139                                event = true;
 140                        break;
 141                default:
 142                        /* one edge per byte */
 143                        if (v & 2) {
 144                                b = ffz(v | 1);
 145                                rawir.pulse = true;
 146                        } else {
 147                                b = ffs(v) - 1;
 148                                rawir.pulse = false;
 149                        }
 150
 151                        rawir.duration = NS_PER_BIT * (8 - b);
 152                        if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 153                                event = true;
 154
 155                        rawir.pulse = !rawir.pulse;
 156                        rawir.duration = NS_PER_BIT * b;
 157                        if (ir_raw_event_store_with_filter(tt->rc, &rawir))
 158                                event = true;
 159                        break;
 160                }
 161        }
 162
 163        /* don't wakeup when there's nothing to do */
 164        if (event)
 165                ir_raw_event_handle(tt->rc);
 166}
 167
 168static void ttusbir_urb_complete(struct urb *urb)
 169{
 170        struct ttusbir *tt = urb->context;
 171        int rc;
 172
 173        switch (urb->status) {
 174        case 0:
 175                ttusbir_process_ir_data(tt, urb->transfer_buffer);
 176                break;
 177        case -ECONNRESET:
 178        case -ENOENT:
 179        case -ESHUTDOWN:
 180                usb_unlink_urb(urb);
 181                return;
 182        case -EPIPE:
 183        default:
 184                dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
 185                break;
 186        }
 187
 188        rc = usb_submit_urb(urb, GFP_ATOMIC);
 189        if (rc && rc != -ENODEV)
 190                dev_warn(tt->dev, "failed to resubmit urb: %d\n", rc);
 191}
 192
 193static int ttusbir_probe(struct usb_interface *intf,
 194                         const struct usb_device_id *id)
 195{
 196        struct ttusbir *tt;
 197        struct usb_interface_descriptor *idesc;
 198        struct usb_endpoint_descriptor *desc;
 199        struct rc_dev *rc;
 200        int i, j, ret;
 201        int altsetting = -1;
 202
 203        tt = kzalloc(sizeof(*tt), GFP_KERNEL);
 204        rc = rc_allocate_device(RC_DRIVER_IR_RAW);
 205        if (!tt || !rc) {
 206                ret = -ENOMEM;
 207                goto out;
 208        }
 209
 210        /* find the correct alt setting */
 211        for (i = 0; i < intf->num_altsetting && altsetting == -1; i++) {
 212                int max_packet, bulk_out_endp = -1, iso_in_endp = -1;
 213
 214                idesc = &intf->altsetting[i].desc;
 215
 216                for (j = 0; j < idesc->bNumEndpoints; j++) {
 217                        desc = &intf->altsetting[i].endpoint[j].desc;
 218                        max_packet = le16_to_cpu(desc->wMaxPacketSize);
 219                        if (usb_endpoint_dir_in(desc) &&
 220                                        usb_endpoint_xfer_isoc(desc) &&
 221                                        max_packet == 0x10)
 222                                iso_in_endp = j;
 223                        else if (usb_endpoint_dir_out(desc) &&
 224                                        usb_endpoint_xfer_bulk(desc) &&
 225                                        max_packet == 0x20)
 226                                bulk_out_endp = j;
 227
 228                        if (bulk_out_endp != -1 && iso_in_endp != -1) {
 229                                tt->bulk_out_endp = bulk_out_endp;
 230                                tt->iso_in_endp = iso_in_endp;
 231                                altsetting = i;
 232                                break;
 233                        }
 234                }
 235        }
 236
 237        if (altsetting == -1) {
 238                dev_err(&intf->dev, "cannot find expected altsetting\n");
 239                ret = -ENODEV;
 240                goto out;
 241        }
 242
 243        tt->dev = &intf->dev;
 244        tt->udev = interface_to_usbdev(intf);
 245        tt->rc = rc;
 246
 247        ret = usb_set_interface(tt->udev, 0, altsetting);
 248        if (ret)
 249                goto out;
 250
 251        for (i = 0; i < NUM_URBS; i++) {
 252                struct urb *urb = usb_alloc_urb(8, GFP_KERNEL);
 253                void *buffer;
 254
 255                if (!urb) {
 256                        ret = -ENOMEM;
 257                        goto out;
 258                }
 259
 260                urb->dev = tt->udev;
 261                urb->context = tt;
 262                urb->pipe = usb_rcvisocpipe(tt->udev, tt->iso_in_endp);
 263                urb->interval = 1;
 264                buffer = usb_alloc_coherent(tt->udev, 128, GFP_KERNEL,
 265                                                &urb->transfer_dma);
 266                if (!buffer) {
 267                        usb_free_urb(urb);
 268                        ret = -ENOMEM;
 269                        goto out;
 270                }
 271                urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP | URB_ISO_ASAP;
 272                urb->transfer_buffer = buffer;
 273                urb->complete = ttusbir_urb_complete;
 274                urb->number_of_packets = 8;
 275                urb->transfer_buffer_length = 128;
 276
 277                for (j = 0; j < 8; j++) {
 278                        urb->iso_frame_desc[j].offset = j * 16;
 279                        urb->iso_frame_desc[j].length = 16;
 280                }
 281
 282                tt->urb[i] = urb;
 283        }
 284
 285        tt->bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
 286        if (!tt->bulk_urb) {
 287                ret = -ENOMEM;
 288                goto out;
 289        }
 290
 291        tt->bulk_buffer[0] = 0xaa;
 292        tt->bulk_buffer[1] = 0x01;
 293        tt->bulk_buffer[2] = 0x05;
 294        tt->bulk_buffer[3] = 0x01;
 295
 296        usb_fill_bulk_urb(tt->bulk_urb, tt->udev, usb_sndbulkpipe(tt->udev,
 297                tt->bulk_out_endp), tt->bulk_buffer, sizeof(tt->bulk_buffer),
 298                                                ttusbir_bulk_complete, tt);
 299
 300        tt->led.name = "ttusbir:green:power";
 301        tt->led.default_trigger = "rc-feedback";
 302        tt->led.brightness_set = ttusbir_brightness_set;
 303        tt->led.brightness_get = ttusbir_brightness_get;
 304        tt->is_led_on = tt->led_on = true;
 305        atomic_set(&tt->led_complete, 0);
 306        ret = led_classdev_register(&intf->dev, &tt->led);
 307        if (ret)
 308                goto out;
 309
 310        usb_make_path(tt->udev, tt->phys, sizeof(tt->phys));
 311
 312        rc->device_name = DRIVER_DESC;
 313        rc->input_phys = tt->phys;
 314        usb_to_input_id(tt->udev, &rc->input_id);
 315        rc->dev.parent = &intf->dev;
 316        rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
 317        rc->priv = tt;
 318        rc->driver_name = DRIVER_NAME;
 319        rc->map_name = RC_MAP_TT_1500;
 320        rc->min_timeout = 1;
 321        rc->timeout = IR_DEFAULT_TIMEOUT;
 322        rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
 323
 324        /*
 325         * The precision is NS_PER_BIT, but since every 8th bit can be
 326         * overwritten with garbage the accuracy is at best 2 * NS_PER_BIT.
 327         */
 328        rc->rx_resolution = NS_PER_BIT;
 329
 330        ret = rc_register_device(rc);
 331        if (ret) {
 332                dev_err(&intf->dev, "failed to register rc device %d\n", ret);
 333                goto out2;
 334        }
 335
 336        usb_set_intfdata(intf, tt);
 337
 338        for (i = 0; i < NUM_URBS; i++) {
 339                ret = usb_submit_urb(tt->urb[i], GFP_KERNEL);
 340                if (ret) {
 341                        dev_err(tt->dev, "failed to submit urb %d\n", ret);
 342                        goto out3;
 343                }
 344        }
 345
 346        return 0;
 347out3:
 348        rc_unregister_device(rc);
 349        rc = NULL;
 350out2:
 351        led_classdev_unregister(&tt->led);
 352out:
 353        if (tt) {
 354                for (i = 0; i < NUM_URBS && tt->urb[i]; i++) {
 355                        struct urb *urb = tt->urb[i];
 356
 357                        usb_kill_urb(urb);
 358                        usb_free_coherent(tt->udev, 128, urb->transfer_buffer,
 359                                                        urb->transfer_dma);
 360                        usb_free_urb(urb);
 361                }
 362                usb_kill_urb(tt->bulk_urb);
 363                usb_free_urb(tt->bulk_urb);
 364                kfree(tt);
 365        }
 366        rc_free_device(rc);
 367
 368        return ret;
 369}
 370
 371static void ttusbir_disconnect(struct usb_interface *intf)
 372{
 373        struct ttusbir *tt = usb_get_intfdata(intf);
 374        struct usb_device *udev = tt->udev;
 375        int i;
 376
 377        tt->udev = NULL;
 378
 379        rc_unregister_device(tt->rc);
 380        led_classdev_unregister(&tt->led);
 381        for (i = 0; i < NUM_URBS; i++) {
 382                usb_kill_urb(tt->urb[i]);
 383                usb_free_coherent(udev, 128, tt->urb[i]->transfer_buffer,
 384                                                tt->urb[i]->transfer_dma);
 385                usb_free_urb(tt->urb[i]);
 386        }
 387        usb_kill_urb(tt->bulk_urb);
 388        usb_free_urb(tt->bulk_urb);
 389        usb_set_intfdata(intf, NULL);
 390        kfree(tt);
 391}
 392
 393static int ttusbir_suspend(struct usb_interface *intf, pm_message_t message)
 394{
 395        struct ttusbir *tt = usb_get_intfdata(intf);
 396        int i;
 397
 398        for (i = 0; i < NUM_URBS; i++)
 399                usb_kill_urb(tt->urb[i]);
 400
 401        led_classdev_suspend(&tt->led);
 402        usb_kill_urb(tt->bulk_urb);
 403
 404        return 0;
 405}
 406
 407static int ttusbir_resume(struct usb_interface *intf)
 408{
 409        struct ttusbir *tt = usb_get_intfdata(intf);
 410        int i, rc;
 411
 412        tt->is_led_on = true;
 413        led_classdev_resume(&tt->led);
 414
 415        for (i = 0; i < NUM_URBS; i++) {
 416                rc = usb_submit_urb(tt->urb[i], GFP_KERNEL);
 417                if (rc) {
 418                        dev_warn(tt->dev, "failed to submit urb: %d\n", rc);
 419                        break;
 420                }
 421        }
 422
 423        return rc;
 424}
 425
 426static const struct usb_device_id ttusbir_table[] = {
 427        { USB_DEVICE(0x0b48, 0x2003) },
 428        { }
 429};
 430
 431static struct usb_driver ttusbir_driver = {
 432        .name = DRIVER_NAME,
 433        .id_table = ttusbir_table,
 434        .probe = ttusbir_probe,
 435        .suspend = ttusbir_suspend,
 436        .resume = ttusbir_resume,
 437        .reset_resume = ttusbir_resume,
 438        .disconnect = ttusbir_disconnect,
 439};
 440
 441module_usb_driver(ttusbir_driver);
 442
 443MODULE_DESCRIPTION(DRIVER_DESC);
 444MODULE_AUTHOR("Sean Young <sean@mess.org>");
 445MODULE_LICENSE("GPL");
 446MODULE_DEVICE_TABLE(usb, ttusbir_table);
 447
 448