drivers/usb/serial/ir-usb.c

   1 /*
   2  * USB IR Dongle driver
   3  *
   4  *      Copyright (C) 2001-2002 Greg Kroah-Hartman (greg@kroah.com)
   5  *      Copyright (C) 2002      Gary Brubaker (xavyer@ix.netcom.com)
   6  *      Copyright (C) 2010      Johan Hovold (jhovold@gmail.com)
   7  *
   8  *      This program is free software; you can redistribute it and/or modify
   9  *      it under the terms of the GNU General Public License as published by
  10  *      the Free Software Foundation; either version 2 of the License, or
  11  *      (at your option) any later version.
  12  *
  13  * This driver allows a USB IrDA device to be used as a "dumb" serial device.
  14  * This can be useful if you do not have access to a full IrDA stack on the
  15  * other side of the connection.  If you do have an IrDA stack on both devices,
  16  * please use the usb-irda driver, as it contains the proper error checking and
  17  * other goodness of a full IrDA stack.
  18  *
  19  * Portions of this driver were taken from drivers/net/irda/irda-usb.c, which
  20  * was written by Roman Weissgaerber <weissg@vienna.at>, Dag Brattli
  21  * <dag@brattli.net>, and Jean Tourrilhes <jt@hpl.hp.com>
  22  *
  23  * See Documentation/usb/usb-serial.txt for more information on using this
  24  * driver
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/errno.h>
  29 #include <linux/init.h>
  30 #include <linux/slab.h>
  31 #include <linux/tty.h>
  32 #include <linux/tty_driver.h>
  33 #include <linux/tty_flip.h>
  34 #include <linux/module.h>
  35 #include <linux/spinlock.h>
  36 #include <linux/uaccess.h>
  37 #include <linux/usb.h>
  38 #include <linux/usb/serial.h>
  39 #include <linux/usb/irda.h>
  40
  41 /*
  42  * Version Information
  43  */
  44 #define DRIVER_VERSION "v0.5"
  45 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Johan Hovold <jhovold@gmail.com>"
  46 #define DRIVER_DESC "USB IR Dongle driver"
  47
  48 static bool debug;
  49
  50 /* if overridden by the user, then use their value for the size of the read and
  51  * write urbs */
  52 static int buffer_size;
  53
  54 /* if overridden by the user, then use the specified number of XBOFs */
  55 static int xbof = -1;
  56
  57 static int  ir_startup (struct usb_serial *serial);
  58 static int  ir_open(struct tty_struct *tty, struct usb_serial_port *port);
  59 static int ir_prepare_write_buffer(struct usb_serial_port *port,
  60                                                 void *dest, size_t size);
  61 static void ir_process_read_urb(struct urb *urb);
  62 static void ir_set_termios(struct tty_struct *tty,
  63                 struct usb_serial_port *port, struct ktermios *old_termios);
  64
  65 /* Not that this lot means you can only have one per system */
  66 static u8 ir_baud;
  67 static u8 ir_xbof;
  68 static u8 ir_add_bof;
  69
  70 static const struct usb_device_id ir_id_table[] = {
  71         { USB_DEVICE(0x050f, 0x0180) },         /* KC Technology, KC-180 */
  72         { USB_DEVICE(0x08e9, 0x0100) },         /* XTNDAccess */
  73         { USB_DEVICE(0x09c4, 0x0011) },         /* ACTiSys ACT-IR2000U */
  74         { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, USB_SUBCLASS_IRDA, 0) },
  75         { }                                     /* Terminating entry */
  76 };
  77
  78 MODULE_DEVICE_TABLE(usb, ir_id_table);
  79
  80 static struct usb_driver ir_driver = {
  81         .name           = "ir-usb",
  82         .probe          = usb_serial_probe,
  83         .disconnect     = usb_serial_disconnect,
  84         .id_table       = ir_id_table,
  85         .no_dynamic_id  = 1,
  86 };
  87
  88 static struct usb_serial_driver ir_device = {
  89         .driver = {
  90                 .owner  = THIS_MODULE,
  91                 .name   = "ir-usb",
  92         },
  93         .description            = "IR Dongle",
  94         .usb_driver             = &ir_driver,
  95         .id_table               = ir_id_table,
  96         .num_ports              = 1,
  97         .set_termios            = ir_set_termios,
  98         .attach                 = ir_startup,
  99         .open                   = ir_open,
 100         .prepare_write_buffer   = ir_prepare_write_buffer,
 101         .process_read_urb       = ir_process_read_urb,
 102 };
 103
 104 static inline void irda_usb_dump_class_desc(struct usb_irda_cs_descriptor *desc)
 105 {
 106         dbg("bLength=%x", desc->bLength);
 107         dbg("bDescriptorType=%x", desc->bDescriptorType);
 108         dbg("bcdSpecRevision=%x", __le16_to_cpu(desc->bcdSpecRevision));
 109         dbg("bmDataSize=%x", desc->bmDataSize);
 110         dbg("bmWindowSize=%x", desc->bmWindowSize);
 111         dbg("bmMinTurnaroundTime=%d", desc->bmMinTurnaroundTime);
 112         dbg("wBaudRate=%x", __le16_to_cpu(desc->wBaudRate));
 113         dbg("bmAdditionalBOFs=%x", desc->bmAdditionalBOFs);
 114         dbg("bIrdaRateSniff=%x", desc->bIrdaRateSniff);
 115         dbg("bMaxUnicastList=%x", desc->bMaxUnicastList);
 116 }
 117
 118 /*------------------------------------------------------------------*/
 119 /*
 120  * Function irda_usb_find_class_desc(dev, ifnum)
 121  *
 122  *    Returns instance of IrDA class descriptor, or NULL if not found
 123  *
 124  * The class descriptor is some extra info that IrDA USB devices will
 125  * offer to us, describing their IrDA characteristics. We will use that in
 126  * irda_usb_init_qos()
 127  *
 128  * Based on the same function in drivers/net/irda/irda-usb.c
 129  */
 130 static struct usb_irda_cs_descriptor *
 131 irda_usb_find_class_desc(struct usb_device *dev, unsigned int ifnum)
 132 {
 133         struct usb_irda_cs_descriptor *desc;
 134         int ret;
 135
 136         desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 137         if (!desc)
 138                 return NULL;
 139
 140         ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 141                         USB_REQ_CS_IRDA_GET_CLASS_DESC,
 142                         USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 143                         0, ifnum, desc, sizeof(*desc), 1000);
 144
 145         dbg("%s -  ret=%d", __func__, ret);
 146         if (ret < sizeof(*desc)) {
 147                 dbg("%s - class descriptor read %s (%d)",
 148                                 __func__,
 149                                 (ret < 0) ? "failed" : "too short",
 150                                 ret);
 151                 goto error;
 152         }
 153         if (desc->bDescriptorType != USB_DT_CS_IRDA) {
 154                 dbg("%s - bad class descriptor type", __func__);
 155                 goto error;
 156         }
 157
 158         irda_usb_dump_class_desc(desc);
 159         return desc;
 160
 161 error:
 162         kfree(desc);
 163         return NULL;
 164 }
 165
 166 static u8 ir_xbof_change(u8 xbof)
 167 {
 168         u8 result;
 169
 170         /* reference irda-usb.c */
 171         switch (xbof) {
 172         case 48:
 173                 result = 0x10;
 174                 break;
 175         case 28:
 176         case 24:
 177                 result = 0x20;
 178                 break;
 179         default:
 180         case 12:
 181                 result = 0x30;
 182                 break;
 183         case  5:
 184         case  6:
 185                 result = 0x40;
 186                 break;
 187         case  3:
 188                 result = 0x50;
 189                 break;
 190         case  2:
 191                 result = 0x60;
 192                 break;
 193         case  1:
 194                 result = 0x70;
 195                 break;
 196         case  0:
 197                 result = 0x80;
 198                 break;
 199         }
 200
 201         return(result);
 202 }
 203
 204 static int ir_startup(struct usb_serial *serial)
 205 {
 206         struct usb_irda_cs_descriptor *irda_desc;
 207
 208         irda_desc = irda_usb_find_class_desc(serial->dev, 0);
 209         if (!irda_desc) {
 210                 dev_err(&serial->dev->dev,
 211                         "IRDA class descriptor not found, device not bound\n");
 212                 return -ENODEV;
 213         }
 214
 215         dbg("%s - Baud rates supported:%s%s%s%s%s%s%s%s%s",
 216                 __func__,
 217                 (irda_desc->wBaudRate & USB_IRDA_BR_2400) ? " 2400" : "",
 218                 (irda_desc->wBaudRate & USB_IRDA_BR_9600) ? " 9600" : "",
 219                 (irda_desc->wBaudRate & USB_IRDA_BR_19200) ? " 19200" : "",
 220                 (irda_desc->wBaudRate & USB_IRDA_BR_38400) ? " 38400" : "",
 221                 (irda_desc->wBaudRate & USB_IRDA_BR_57600) ? " 57600" : "",
 222                 (irda_desc->wBaudRate & USB_IRDA_BR_115200) ? " 115200" : "",
 223                 (irda_desc->wBaudRate & USB_IRDA_BR_576000) ? " 576000" : "",
 224                 (irda_desc->wBaudRate & USB_IRDA_BR_1152000) ? " 1152000" : "",
 225                 (irda_desc->wBaudRate & USB_IRDA_BR_4000000) ? " 4000000" : "");
 226
 227         switch (irda_desc->bmAdditionalBOFs) {
 228         case USB_IRDA_AB_48:
 229                 ir_add_bof = 48;
 230                 break;
 231         case USB_IRDA_AB_24:
 232                 ir_add_bof = 24;
 233                 break;
 234         case USB_IRDA_AB_12:
 235                 ir_add_bof = 12;
 236                 break;
 237         case USB_IRDA_AB_6:
 238                 ir_add_bof = 6;
 239                 break;
 240         case USB_IRDA_AB_3:
 241                 ir_add_bof = 3;
 242                 break;
 243         case USB_IRDA_AB_2:
 244                 ir_add_bof = 2;
 245                 break;
 246         case USB_IRDA_AB_1:
 247                 ir_add_bof = 1;
 248                 break;
 249         case USB_IRDA_AB_0:
 250                 ir_add_bof = 0;
 251                 break;
 252         default:
 253                 break;
 254         }
 255
 256         kfree(irda_desc);
 257
 258         return 0;
 259 }
 260
 261 static int ir_open(struct tty_struct *tty, struct usb_serial_port *port)
 262 {
 263         int i;
 264
 265         dbg("%s - port %d", __func__, port->number);
 266
 267         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 268                 port->write_urbs[i]->transfer_flags = URB_ZERO_PACKET;
 269
 270         /* Start reading from the device */
 271         return usb_serial_generic_open(tty, port);
 272 }
 273
 274 static int ir_prepare_write_buffer(struct usb_serial_port *port,
 275                                                 void *dest, size_t size)
 276 {
 277         unsigned char *buf = dest;
 278         int count;
 279
 280         /*
 281          * The first byte of the packet we send to the device contains an
 282          * inbound header which indicates an additional number of BOFs and
 283          * a baud rate change.
 284          *
 285          * See section 5.4.2.2 of the USB IrDA spec.
 286          */
 287         *buf = ir_xbof | ir_baud;
 288
 289         count = kfifo_out_locked(&port->write_fifo, buf + 1, size - 1,
 290                                                                 &port->lock);
 291         return count + 1;
 292 }
 293
 294 static void ir_process_read_urb(struct urb *urb)
 295 {
 296         struct usb_serial_port *port = urb->context;
 297         unsigned char *data = urb->transfer_buffer;
 298         struct tty_struct *tty;
 299
 300         if (!urb->actual_length)
 301                 return;
 302         /*
 303          * The first byte of the packet we get from the device
 304          * contains a busy indicator and baud rate change.
 305          * See section 5.4.1.2 of the USB IrDA spec.
 306          */
 307         if (*data & 0x0f)
 308                 ir_baud = *data & 0x0f;
 309
 310         if (urb->actual_length == 1)
 311                 return;
 312
 313         tty = tty_port_tty_get(&port->port);
 314         if (!tty)
 315                 return;
 316         tty_insert_flip_string(tty, data + 1, urb->actual_length - 1);
 317         tty_flip_buffer_push(tty);
 318         tty_kref_put(tty);
 319 }
 320
 321 static void ir_set_termios_callback(struct urb *urb)
 322 {
 323         struct usb_serial_port *port = urb->context;
 324         int status = urb->status;
 325
 326         dbg("%s - port %d", __func__, port->number);
 327
 328         kfree(urb->transfer_buffer);
 329
 330         if (status)
 331                 dbg("%s - non-zero urb status: %d", __func__, status);
 332 }
 333
 334 static void ir_set_termios(struct tty_struct *tty,
 335                 struct usb_serial_port *port, struct ktermios *old_termios)
 336 {
 337         struct urb *urb;
 338         unsigned char *transfer_buffer;
 339         int result;
 340         speed_t baud;
 341         int ir_baud;
 342
 343         dbg("%s - port %d", __func__, port->number);
 344
 345         baud = tty_get_baud_rate(tty);
 346
 347         /*
 348          * FIXME, we should compare the baud request against the
 349          * capability stated in the IR header that we got in the
 350          * startup function.
 351          */
 352
 353         switch (baud) {
 354         case 2400:
 355                 ir_baud = USB_IRDA_BR_2400;
 356                 break;
 357         case 9600:
 358                 ir_baud = USB_IRDA_BR_9600;
 359                 break;
 360         case 19200:
 361                 ir_baud = USB_IRDA_BR_19200;
 362                 break;
 363         case 38400:
 364                 ir_baud = USB_IRDA_BR_38400;
 365                 break;
 366         case 57600:
 367                 ir_baud = USB_IRDA_BR_57600;
 368                 break;
 369         case 115200:
 370                 ir_baud = USB_IRDA_BR_115200;
 371                 break;
 372         case 576000:
 373                 ir_baud = USB_IRDA_BR_576000;
 374                 break;
 375         case 1152000:
 376                 ir_baud = USB_IRDA_BR_1152000;
 377                 break;
 378         case 4000000:
 379                 ir_baud = USB_IRDA_BR_4000000;
 380                 break;
 381         default:
 382                 ir_baud = USB_IRDA_BR_9600;
 383                 baud = 9600;
 384         }
 385
 386         if (xbof == -1)
 387                 ir_xbof = ir_xbof_change(ir_add_bof);
 388         else
 389                 ir_xbof = ir_xbof_change(xbof) ;
 390
 391         /* Only speed changes are supported */
 392         tty_termios_copy_hw(tty->termios, old_termios);
 393         tty_encode_baud_rate(tty, baud, baud);
 394
 395         /*
 396          * send the baud change out on an "empty" data packet
 397          */
 398         urb = usb_alloc_urb(0, GFP_KERNEL);
 399         if (!urb) {
 400                 dev_err(&port->dev, "%s - no more urbs\n", __func__);
 401                 return;
 402         }
 403         transfer_buffer = kmalloc(1, GFP_KERNEL);
 404         if (!transfer_buffer) {
 405                 dev_err(&port->dev, "%s - out of memory\n", __func__);
 406                 goto err_buf;
 407         }
 408
 409         *transfer_buffer = ir_xbof | ir_baud;
 410
 411         usb_fill_bulk_urb(
 412                 urb,
 413                 port->serial->dev,
 414                 usb_sndbulkpipe(port->serial->dev,
 415                         port->bulk_out_endpointAddress),
 416                 transfer_buffer,
 417                 1,
 418                 ir_set_termios_callback,
 419                 port);
 420
 421         urb->transfer_flags = URB_ZERO_PACKET;
 422
 423         result = usb_submit_urb(urb, GFP_KERNEL);
 424         if (result) {
 425                 dev_err(&port->dev, "%s - failed to submit urb: %d\n",
 426                                                         __func__, result);
 427                 goto err_subm;
 428         }
 429
 430         usb_free_urb(urb);
 431
 432         return;
 433 err_subm:
 434         kfree(transfer_buffer);
 435 err_buf:
 436         usb_free_urb(urb);
 437 }
 438
 439 static int __init ir_init(void)
 440 {
 441         int retval;
 442
 443         if (buffer_size) {
 444                 ir_device.bulk_in_size = buffer_size;
 445                 ir_device.bulk_out_size = buffer_size;
 446         }
 447
 448         retval = usb_serial_register(&ir_device);
 449         if (retval)
 450                 goto failed_usb_serial_register;
 451
 452         retval = usb_register(&ir_driver);
 453         if (retval)
 454                 goto failed_usb_register;
 455
 456         printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
 457                DRIVER_DESC "\n");
 458
 459         return 0;
 460
 461 failed_usb_register:
 462         usb_serial_deregister(&ir_device);
 463
 464 failed_usb_serial_register:
 465         return retval;
 466 }
 467
 468 static void __exit ir_exit(void)
 469 {
 470         usb_deregister(&ir_driver);
 471         usb_serial_deregister(&ir_device);
 472 }
 473
 474
 475 module_init(ir_init);
 476 module_exit(ir_exit);
 477
 478 MODULE_AUTHOR(DRIVER_AUTHOR);
 479 MODULE_DESCRIPTION(DRIVER_DESC);
 480 MODULE_LICENSE("GPL");
 481
 482 module_param(debug, bool, S_IRUGO | S_IWUSR);
 483 MODULE_PARM_DESC(debug, "Debug enabled or not");
 484 module_param(xbof, int, 0);
 485 MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
 486 module_param(buffer_size, int, 0);
 487 MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
 488