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 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Johan Hovold <jhovold@gmail.com>"
  42 #define DRIVER_DESC "USB IR Dongle driver"
  43
  44 /* if overridden by the user, then use their value for the size of the read and
  45  * write urbs */
  46 static int buffer_size;
  47
  48 /* if overridden by the user, then use the specified number of XBOFs */
  49 static int xbof = -1;
  50
  51 static int  ir_startup (struct usb_serial *serial);
  52 static int ir_write(struct tty_struct *tty, struct usb_serial_port *port,
  53                 const unsigned char *buf, int count);
  54 static int ir_write_room(struct tty_struct *tty);
  55 static void ir_write_bulk_callback(struct urb *urb);
  56 static void ir_process_read_urb(struct urb *urb);
  57 static void ir_set_termios(struct tty_struct *tty,
  58                 struct usb_serial_port *port, struct ktermios *old_termios);
  59
  60 /* Not that this lot means you can only have one per system */
  61 static u8 ir_baud;
  62 static u8 ir_xbof;
  63 static u8 ir_add_bof;
  64
  65 static const struct usb_device_id ir_id_table[] = {
  66         { USB_DEVICE(0x050f, 0x0180) },         /* KC Technology, KC-180 */
  67         { USB_DEVICE(0x08e9, 0x0100) },         /* XTNDAccess */
  68         { USB_DEVICE(0x09c4, 0x0011) },         /* ACTiSys ACT-IR2000U */
  69         { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, USB_SUBCLASS_IRDA, 0) },
  70         { }                                     /* Terminating entry */
  71 };
  72
  73 MODULE_DEVICE_TABLE(usb, ir_id_table);
  74
  75 static struct usb_serial_driver ir_device = {
  76         .driver = {
  77                 .owner  = THIS_MODULE,
  78                 .name   = "ir-usb",
  79         },
  80         .description            = "IR Dongle",
  81         .id_table               = ir_id_table,
  82         .num_ports              = 1,
  83         .set_termios            = ir_set_termios,
  84         .attach                 = ir_startup,
  85         .write                  = ir_write,
  86         .write_room             = ir_write_room,
  87         .write_bulk_callback    = ir_write_bulk_callback,
  88         .process_read_urb       = ir_process_read_urb,
  89 };
  90
  91 static struct usb_serial_driver * const serial_drivers[] = {
  92         &ir_device, NULL
  93 };
  94
  95 static inline void irda_usb_dump_class_desc(struct usb_serial *serial,
  96                                             struct usb_irda_cs_descriptor *desc)
  97 {
  98         struct device *dev = &serial->dev->dev;
  99
 100         dev_dbg(dev, "bLength=%x\n", desc->bLength);
 101         dev_dbg(dev, "bDescriptorType=%x\n", desc->bDescriptorType);
 102         dev_dbg(dev, "bcdSpecRevision=%x\n", __le16_to_cpu(desc->bcdSpecRevision));
 103         dev_dbg(dev, "bmDataSize=%x\n", desc->bmDataSize);
 104         dev_dbg(dev, "bmWindowSize=%x\n", desc->bmWindowSize);
 105         dev_dbg(dev, "bmMinTurnaroundTime=%d\n", desc->bmMinTurnaroundTime);
 106         dev_dbg(dev, "wBaudRate=%x\n", __le16_to_cpu(desc->wBaudRate));
 107         dev_dbg(dev, "bmAdditionalBOFs=%x\n", desc->bmAdditionalBOFs);
 108         dev_dbg(dev, "bIrdaRateSniff=%x\n", desc->bIrdaRateSniff);
 109         dev_dbg(dev, "bMaxUnicastList=%x\n", desc->bMaxUnicastList);
 110 }
 111
 112 /*------------------------------------------------------------------*/
 113 /*
 114  * Function irda_usb_find_class_desc(dev, ifnum)
 115  *
 116  *    Returns instance of IrDA class descriptor, or NULL if not found
 117  *
 118  * The class descriptor is some extra info that IrDA USB devices will
 119  * offer to us, describing their IrDA characteristics. We will use that in
 120  * irda_usb_init_qos()
 121  *
 122  * Based on the same function in drivers/net/irda/irda-usb.c
 123  */
 124 static struct usb_irda_cs_descriptor *
 125 irda_usb_find_class_desc(struct usb_serial *serial, unsigned int ifnum)
 126 {
 127         struct usb_device *dev = serial->dev;
 128         struct usb_irda_cs_descriptor *desc;
 129         int ret;
 130
 131         desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 132         if (!desc)
 133                 return NULL;
 134
 135         ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 136                         USB_REQ_CS_IRDA_GET_CLASS_DESC,
 137                         USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 138                         0, ifnum, desc, sizeof(*desc), 1000);
 139
 140         dev_dbg(&serial->dev->dev, "%s -  ret=%d\n", __func__, ret);
 141         if (ret < sizeof(*desc)) {
 142                 dev_dbg(&serial->dev->dev,
 143                         "%s - class descriptor read %s (%d)\n", __func__,
 144                         (ret < 0) ? "failed" : "too short", ret);
 145                 goto error;
 146         }
 147         if (desc->bDescriptorType != USB_DT_CS_IRDA) {
 148                 dev_dbg(&serial->dev->dev, "%s - bad class descriptor type\n",
 149                         __func__);
 150                 goto error;
 151         }
 152
 153         irda_usb_dump_class_desc(serial, desc);
 154         return desc;
 155
 156 error:
 157         kfree(desc);
 158         return NULL;
 159 }
 160
 161 static u8 ir_xbof_change(u8 xbof)
 162 {
 163         u8 result;
 164
 165         /* reference irda-usb.c */
 166         switch (xbof) {
 167         case 48:
 168                 result = 0x10;
 169                 break;
 170         case 28:
 171         case 24:
 172                 result = 0x20;
 173                 break;
 174         default:
 175         case 12:
 176                 result = 0x30;
 177                 break;
 178         case  5:
 179         case  6:
 180                 result = 0x40;
 181                 break;
 182         case  3:
 183                 result = 0x50;
 184                 break;
 185         case  2:
 186                 result = 0x60;
 187                 break;
 188         case  1:
 189                 result = 0x70;
 190                 break;
 191         case  0:
 192                 result = 0x80;
 193                 break;
 194         }
 195
 196         return(result);
 197 }
 198
 199 static int ir_startup(struct usb_serial *serial)
 200 {
 201         struct usb_irda_cs_descriptor *irda_desc;
 202
 203         if (serial->num_bulk_in < 1 || serial->num_bulk_out < 1)
 204                 return -ENODEV;
 205
 206         irda_desc = irda_usb_find_class_desc(serial, 0);
 207         if (!irda_desc) {
 208                 dev_err(&serial->dev->dev,
 209                         "IRDA class descriptor not found, device not bound\n");
 210                 return -ENODEV;
 211         }
 212
 213         dev_dbg(&serial->dev->dev,
 214                 "%s - Baud rates supported:%s%s%s%s%s%s%s%s%s\n",
 215                 __func__,
 216                 (irda_desc->wBaudRate & USB_IRDA_BR_2400) ? " 2400" : "",
 217                 (irda_desc->wBaudRate & USB_IRDA_BR_9600) ? " 9600" : "",
 218                 (irda_desc->wBaudRate & USB_IRDA_BR_19200) ? " 19200" : "",
 219                 (irda_desc->wBaudRate & USB_IRDA_BR_38400) ? " 38400" : "",
 220                 (irda_desc->wBaudRate & USB_IRDA_BR_57600) ? " 57600" : "",
 221                 (irda_desc->wBaudRate & USB_IRDA_BR_115200) ? " 115200" : "",
 222                 (irda_desc->wBaudRate & USB_IRDA_BR_576000) ? " 576000" : "",
 223                 (irda_desc->wBaudRate & USB_IRDA_BR_1152000) ? " 1152000" : "",
 224                 (irda_desc->wBaudRate & USB_IRDA_BR_4000000) ? " 4000000" : "");
 225
 226         switch (irda_desc->bmAdditionalBOFs) {
 227         case USB_IRDA_AB_48:
 228                 ir_add_bof = 48;
 229                 break;
 230         case USB_IRDA_AB_24:
 231                 ir_add_bof = 24;
 232                 break;
 233         case USB_IRDA_AB_12:
 234                 ir_add_bof = 12;
 235                 break;
 236         case USB_IRDA_AB_6:
 237                 ir_add_bof = 6;
 238                 break;
 239         case USB_IRDA_AB_3:
 240                 ir_add_bof = 3;
 241                 break;
 242         case USB_IRDA_AB_2:
 243                 ir_add_bof = 2;
 244                 break;
 245         case USB_IRDA_AB_1:
 246                 ir_add_bof = 1;
 247                 break;
 248         case USB_IRDA_AB_0:
 249                 ir_add_bof = 0;
 250                 break;
 251         default:
 252                 break;
 253         }
 254
 255         kfree(irda_desc);
 256
 257         return 0;
 258 }
 259
 260 static int ir_write(struct tty_struct *tty, struct usb_serial_port *port,
 261                 const unsigned char *buf, int count)
 262 {
 263         struct urb *urb = NULL;
 264         unsigned long flags;
 265         int ret;
 266
 267         if (port->bulk_out_size == 0)
 268                 return -EINVAL;
 269
 270         if (count == 0)
 271                 return 0;
 272
 273         count = min(count, port->bulk_out_size - 1);
 274
 275         spin_lock_irqsave(&port->lock, flags);
 276         if (__test_and_clear_bit(0, &port->write_urbs_free)) {
 277                 urb = port->write_urbs[0];
 278                 port->tx_bytes += count;
 279         }
 280         spin_unlock_irqrestore(&port->lock, flags);
 281
 282         if (!urb)
 283                 return 0;
 284
 285         /*
 286          * The first byte of the packet we send to the device contains an
 287          * outbound header which indicates an additional number of BOFs and
 288          * a baud rate change.
 289          *
 290          * See section 5.4.2.2 of the USB IrDA spec.
 291          */
 292         *(u8 *)urb->transfer_buffer = ir_xbof | ir_baud;
 293
 294         memcpy(urb->transfer_buffer + 1, buf, count);
 295
 296         urb->transfer_buffer_length = count + 1;
 297         urb->transfer_flags = URB_ZERO_PACKET;
 298
 299         ret = usb_submit_urb(urb, GFP_ATOMIC);
 300         if (ret) {
 301                 dev_err(&port->dev, "failed to submit write urb: %d\n", ret);
 302
 303                 spin_lock_irqsave(&port->lock, flags);
 304                 __set_bit(0, &port->write_urbs_free);
 305                 port->tx_bytes -= count;
 306                 spin_unlock_irqrestore(&port->lock, flags);
 307
 308                 return ret;
 309         }
 310
 311         return count;
 312 }
 313
 314 static void ir_write_bulk_callback(struct urb *urb)
 315 {
 316         struct usb_serial_port *port = urb->context;
 317         int status = urb->status;
 318         unsigned long flags;
 319
 320         spin_lock_irqsave(&port->lock, flags);
 321         __set_bit(0, &port->write_urbs_free);
 322         port->tx_bytes -= urb->transfer_buffer_length - 1;
 323         spin_unlock_irqrestore(&port->lock, flags);
 324
 325         switch (status) {
 326         case 0:
 327                 break;
 328         case -ENOENT:
 329         case -ECONNRESET:
 330         case -ESHUTDOWN:
 331                 dev_dbg(&port->dev, "write urb stopped: %d\n", status);
 332                 return;
 333         case -EPIPE:
 334                 dev_err(&port->dev, "write urb stopped: %d\n", status);
 335                 return;
 336         default:
 337                 dev_err(&port->dev, "nonzero write-urb status: %d\n", status);
 338                 break;
 339         }
 340
 341         usb_serial_port_softint(port);
 342 }
 343
 344 static int ir_write_room(struct tty_struct *tty)
 345 {
 346         struct usb_serial_port *port = tty->driver_data;
 347         int count = 0;
 348
 349         if (port->bulk_out_size == 0)
 350                 return 0;
 351
 352         if (test_bit(0, &port->write_urbs_free))
 353                 count = port->bulk_out_size - 1;
 354
 355         return count;
 356 }
 357
 358 static void ir_process_read_urb(struct urb *urb)
 359 {
 360         struct usb_serial_port *port = urb->context;
 361         unsigned char *data = urb->transfer_buffer;
 362
 363         if (!urb->actual_length)
 364                 return;
 365         /*
 366          * The first byte of the packet we get from the device
 367          * contains a busy indicator and baud rate change.
 368          * See section 5.4.1.2 of the USB IrDA spec.
 369          */
 370         if (*data & 0x0f)
 371                 ir_baud = *data & 0x0f;
 372
 373         if (urb->actual_length == 1)
 374                 return;
 375
 376         tty_insert_flip_string(&port->port, data + 1, urb->actual_length - 1);
 377         tty_flip_buffer_push(&port->port);
 378 }
 379
 380 static void ir_set_termios_callback(struct urb *urb)
 381 {
 382         kfree(urb->transfer_buffer);
 383
 384         if (urb->status)
 385                 dev_dbg(&urb->dev->dev, "%s - non-zero urb status: %d\n",
 386                         __func__, urb->status);
 387 }
 388
 389 static void ir_set_termios(struct tty_struct *tty,
 390                 struct usb_serial_port *port, struct ktermios *old_termios)
 391 {
 392         struct urb *urb;
 393         unsigned char *transfer_buffer;
 394         int result;
 395         speed_t baud;
 396         int ir_baud;
 397
 398         baud = tty_get_baud_rate(tty);
 399
 400         /*
 401          * FIXME, we should compare the baud request against the
 402          * capability stated in the IR header that we got in the
 403          * startup function.
 404          */
 405
 406         switch (baud) {
 407         case 2400:
 408                 ir_baud = USB_IRDA_LS_2400;
 409                 break;
 410         case 9600:
 411                 ir_baud = USB_IRDA_LS_9600;
 412                 break;
 413         case 19200:
 414                 ir_baud = USB_IRDA_LS_19200;
 415                 break;
 416         case 38400:
 417                 ir_baud = USB_IRDA_LS_38400;
 418                 break;
 419         case 57600:
 420                 ir_baud = USB_IRDA_LS_57600;
 421                 break;
 422         case 115200:
 423                 ir_baud = USB_IRDA_LS_115200;
 424                 break;
 425         case 576000:
 426                 ir_baud = USB_IRDA_LS_576000;
 427                 break;
 428         case 1152000:
 429                 ir_baud = USB_IRDA_LS_1152000;
 430                 break;
 431         case 4000000:
 432                 ir_baud = USB_IRDA_LS_4000000;
 433                 break;
 434         default:
 435                 ir_baud = USB_IRDA_LS_9600;
 436                 baud = 9600;
 437         }
 438
 439         if (xbof == -1)
 440                 ir_xbof = ir_xbof_change(ir_add_bof);
 441         else
 442                 ir_xbof = ir_xbof_change(xbof) ;
 443
 444         /* Only speed changes are supported */
 445         tty_termios_copy_hw(&tty->termios, old_termios);
 446         tty_encode_baud_rate(tty, baud, baud);
 447
 448         /*
 449          * send the baud change out on an "empty" data packet
 450          */
 451         urb = usb_alloc_urb(0, GFP_KERNEL);
 452         if (!urb)
 453                 return;
 454
 455         transfer_buffer = kmalloc(1, GFP_KERNEL);
 456         if (!transfer_buffer)
 457                 goto err_buf;
 458
 459         *transfer_buffer = ir_xbof | ir_baud;
 460
 461         usb_fill_bulk_urb(
 462                 urb,
 463                 port->serial->dev,
 464                 usb_sndbulkpipe(port->serial->dev,
 465                         port->bulk_out_endpointAddress),
 466                 transfer_buffer,
 467                 1,
 468                 ir_set_termios_callback,
 469                 port);
 470
 471         urb->transfer_flags = URB_ZERO_PACKET;
 472
 473         result = usb_submit_urb(urb, GFP_KERNEL);
 474         if (result) {
 475                 dev_err(&port->dev, "%s - failed to submit urb: %d\n",
 476                                                         __func__, result);
 477                 goto err_subm;
 478         }
 479
 480         usb_free_urb(urb);
 481
 482         return;
 483 err_subm:
 484         kfree(transfer_buffer);
 485 err_buf:
 486         usb_free_urb(urb);
 487 }
 488
 489 static int __init ir_init(void)
 490 {
 491         if (buffer_size) {
 492                 ir_device.bulk_in_size = buffer_size;
 493                 ir_device.bulk_out_size = buffer_size;
 494         }
 495
 496         return usb_serial_register_drivers(serial_drivers, KBUILD_MODNAME, ir_id_table);
 497 }
 498
 499 static void __exit ir_exit(void)
 500 {
 501         usb_serial_deregister_drivers(serial_drivers);
 502 }
 503
 504
 505 module_init(ir_init);
 506 module_exit(ir_exit);
 507
 508 MODULE_AUTHOR(DRIVER_AUTHOR);
 509 MODULE_DESCRIPTION(DRIVER_DESC);
 510 MODULE_LICENSE("GPL");
 511
 512 module_param(xbof, int, 0);
 513 MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
 514 module_param(buffer_size, int, 0);
 515 MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
 516