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 };
  86
  87 static struct usb_serial_driver ir_device = {
  88         .driver = {
  89                 .owner  = THIS_MODULE,
  90                 .name   = "ir-usb",
  91         },
  92         .description            = "IR Dongle",
  93         .id_table               = ir_id_table,
  94         .num_ports              = 1,
  95         .set_termios            = ir_set_termios,
  96         .attach                 = ir_startup,
  97         .open                   = ir_open,
  98         .prepare_write_buffer   = ir_prepare_write_buffer,
  99         .process_read_urb       = ir_process_read_urb,
 100 };
 101
 102 static struct usb_serial_driver * const serial_drivers[] = {
 103         &ir_device, NULL
 104 };
 105
 106 static inline void irda_usb_dump_class_desc(struct usb_irda_cs_descriptor *desc)
 107 {
 108         dbg("bLength=%x", desc->bLength);
 109         dbg("bDescriptorType=%x", desc->bDescriptorType);
 110         dbg("bcdSpecRevision=%x", __le16_to_cpu(desc->bcdSpecRevision));
 111         dbg("bmDataSize=%x", desc->bmDataSize);
 112         dbg("bmWindowSize=%x", desc->bmWindowSize);
 113         dbg("bmMinTurnaroundTime=%d", desc->bmMinTurnaroundTime);
 114         dbg("wBaudRate=%x", __le16_to_cpu(desc->wBaudRate));
 115         dbg("bmAdditionalBOFs=%x", desc->bmAdditionalBOFs);
 116         dbg("bIrdaRateSniff=%x", desc->bIrdaRateSniff);
 117         dbg("bMaxUnicastList=%x", desc->bMaxUnicastList);
 118 }
 119
 120 /*------------------------------------------------------------------*/
 121 /*
 122  * Function irda_usb_find_class_desc(dev, ifnum)
 123  *
 124  *    Returns instance of IrDA class descriptor, or NULL if not found
 125  *
 126  * The class descriptor is some extra info that IrDA USB devices will
 127  * offer to us, describing their IrDA characteristics. We will use that in
 128  * irda_usb_init_qos()
 129  *
 130  * Based on the same function in drivers/net/irda/irda-usb.c
 131  */
 132 static struct usb_irda_cs_descriptor *
 133 irda_usb_find_class_desc(struct usb_device *dev, unsigned int ifnum)
 134 {
 135         struct usb_irda_cs_descriptor *desc;
 136         int ret;
 137
 138         desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 139         if (!desc)
 140                 return NULL;
 141
 142         ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 143                         USB_REQ_CS_IRDA_GET_CLASS_DESC,
 144                         USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 145                         0, ifnum, desc, sizeof(*desc), 1000);
 146
 147         dbg("%s -  ret=%d", __func__, ret);
 148         if (ret < sizeof(*desc)) {
 149                 dbg("%s - class descriptor read %s (%d)",
 150                                 __func__,
 151                                 (ret < 0) ? "failed" : "too short",
 152                                 ret);
 153                 goto error;
 154         }
 155         if (desc->bDescriptorType != USB_DT_CS_IRDA) {
 156                 dbg("%s - bad class descriptor type", __func__);
 157                 goto error;
 158         }
 159
 160         irda_usb_dump_class_desc(desc);
 161         return desc;
 162
 163 error:
 164         kfree(desc);
 165         return NULL;
 166 }
 167
 168 static u8 ir_xbof_change(u8 xbof)
 169 {
 170         u8 result;
 171
 172         /* reference irda-usb.c */
 173         switch (xbof) {
 174         case 48:
 175                 result = 0x10;
 176                 break;
 177         case 28:
 178         case 24:
 179                 result = 0x20;
 180                 break;
 181         default:
 182         case 12:
 183                 result = 0x30;
 184                 break;
 185         case  5:
 186         case  6:
 187                 result = 0x40;
 188                 break;
 189         case  3:
 190                 result = 0x50;
 191                 break;
 192         case  2:
 193                 result = 0x60;
 194                 break;
 195         case  1:
 196                 result = 0x70;
 197                 break;
 198         case  0:
 199                 result = 0x80;
 200                 break;
 201         }
 202
 203         return(result);
 204 }
 205
 206 static int ir_startup(struct usb_serial *serial)
 207 {
 208         struct usb_irda_cs_descriptor *irda_desc;
 209
 210         irda_desc = irda_usb_find_class_desc(serial->dev, 0);
 211         if (!irda_desc) {
 212                 dev_err(&serial->dev->dev,
 213                         "IRDA class descriptor not found, device not bound\n");
 214                 return -ENODEV;
 215         }
 216
 217         dbg("%s - Baud rates supported:%s%s%s%s%s%s%s%s%s",
 218                 __func__,
 219                 (irda_desc->wBaudRate & USB_IRDA_BR_2400) ? " 2400" : "",
 220                 (irda_desc->wBaudRate & USB_IRDA_BR_9600) ? " 9600" : "",
 221                 (irda_desc->wBaudRate & USB_IRDA_BR_19200) ? " 19200" : "",
 222                 (irda_desc->wBaudRate & USB_IRDA_BR_38400) ? " 38400" : "",
 223                 (irda_desc->wBaudRate & USB_IRDA_BR_57600) ? " 57600" : "",
 224                 (irda_desc->wBaudRate & USB_IRDA_BR_115200) ? " 115200" : "",
 225                 (irda_desc->wBaudRate & USB_IRDA_BR_576000) ? " 576000" : "",
 226                 (irda_desc->wBaudRate & USB_IRDA_BR_1152000) ? " 1152000" : "",
 227                 (irda_desc->wBaudRate & USB_IRDA_BR_4000000) ? " 4000000" : "");
 228
 229         switch (irda_desc->bmAdditionalBOFs) {
 230         case USB_IRDA_AB_48:
 231                 ir_add_bof = 48;
 232                 break;
 233         case USB_IRDA_AB_24:
 234                 ir_add_bof = 24;
 235                 break;
 236         case USB_IRDA_AB_12:
 237                 ir_add_bof = 12;
 238                 break;
 239         case USB_IRDA_AB_6:
 240                 ir_add_bof = 6;
 241                 break;
 242         case USB_IRDA_AB_3:
 243                 ir_add_bof = 3;
 244                 break;
 245         case USB_IRDA_AB_2:
 246                 ir_add_bof = 2;
 247                 break;
 248         case USB_IRDA_AB_1:
 249                 ir_add_bof = 1;
 250                 break;
 251         case USB_IRDA_AB_0:
 252                 ir_add_bof = 0;
 253                 break;
 254         default:
 255                 break;
 256         }
 257
 258         kfree(irda_desc);
 259
 260         return 0;
 261 }
 262
 263 static int ir_open(struct tty_struct *tty, struct usb_serial_port *port)
 264 {
 265         int i;
 266
 267         dbg("%s - port %d", __func__, port->number);
 268
 269         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 270                 port->write_urbs[i]->transfer_flags = URB_ZERO_PACKET;
 271
 272         /* Start reading from the device */
 273         return usb_serial_generic_open(tty, port);
 274 }
 275
 276 static int ir_prepare_write_buffer(struct usb_serial_port *port,
 277                                                 void *dest, size_t size)
 278 {
 279         unsigned char *buf = dest;
 280         int count;
 281
 282         /*
 283          * The first byte of the packet we send to the device contains an
 284          * inbound header which indicates an additional number of BOFs and
 285          * a baud rate change.
 286          *
 287          * See section 5.4.2.2 of the USB IrDA spec.
 288          */
 289         *buf = ir_xbof | ir_baud;
 290
 291         count = kfifo_out_locked(&port->write_fifo, buf + 1, size - 1,
 292                                                                 &port->lock);
 293         return count + 1;
 294 }
 295
 296 static void ir_process_read_urb(struct urb *urb)
 297 {
 298         struct usb_serial_port *port = urb->context;
 299         unsigned char *data = urb->transfer_buffer;
 300         struct tty_struct *tty;
 301
 302         if (!urb->actual_length)
 303                 return;
 304         /*
 305          * The first byte of the packet we get from the device
 306          * contains a busy indicator and baud rate change.
 307          * See section 5.4.1.2 of the USB IrDA spec.
 308          */
 309         if (*data & 0x0f)
 310                 ir_baud = *data & 0x0f;
 311
 312         if (urb->actual_length == 1)
 313                 return;
 314
 315         tty = tty_port_tty_get(&port->port);
 316         if (!tty)
 317                 return;
 318         tty_insert_flip_string(tty, data + 1, urb->actual_length - 1);
 319         tty_flip_buffer_push(tty);
 320         tty_kref_put(tty);
 321 }
 322
 323 static void ir_set_termios_callback(struct urb *urb)
 324 {
 325         struct usb_serial_port *port = urb->context;
 326         int status = urb->status;
 327
 328         dbg("%s - port %d", __func__, port->number);
 329
 330         kfree(urb->transfer_buffer);
 331
 332         if (status)
 333                 dbg("%s - non-zero urb status: %d", __func__, status);
 334 }
 335
 336 static void ir_set_termios(struct tty_struct *tty,
 337                 struct usb_serial_port *port, struct ktermios *old_termios)
 338 {
 339         struct urb *urb;
 340         unsigned char *transfer_buffer;
 341         int result;
 342         speed_t baud;
 343         int ir_baud;
 344
 345         dbg("%s - port %d", __func__, port->number);
 346
 347         baud = tty_get_baud_rate(tty);
 348
 349         /*
 350          * FIXME, we should compare the baud request against the
 351          * capability stated in the IR header that we got in the
 352          * startup function.
 353          */
 354
 355         switch (baud) {
 356         case 2400:
 357                 ir_baud = USB_IRDA_BR_2400;
 358                 break;
 359         case 9600:
 360                 ir_baud = USB_IRDA_BR_9600;
 361                 break;
 362         case 19200:
 363                 ir_baud = USB_IRDA_BR_19200;
 364                 break;
 365         case 38400:
 366                 ir_baud = USB_IRDA_BR_38400;
 367                 break;
 368         case 57600:
 369                 ir_baud = USB_IRDA_BR_57600;
 370                 break;
 371         case 115200:
 372                 ir_baud = USB_IRDA_BR_115200;
 373                 break;
 374         case 576000:
 375                 ir_baud = USB_IRDA_BR_576000;
 376                 break;
 377         case 1152000:
 378                 ir_baud = USB_IRDA_BR_1152000;
 379                 break;
 380         case 4000000:
 381                 ir_baud = USB_IRDA_BR_4000000;
 382                 break;
 383         default:
 384                 ir_baud = USB_IRDA_BR_9600;
 385                 baud = 9600;
 386         }
 387
 388         if (xbof == -1)
 389                 ir_xbof = ir_xbof_change(ir_add_bof);
 390         else
 391                 ir_xbof = ir_xbof_change(xbof) ;
 392
 393         /* Only speed changes are supported */
 394         tty_termios_copy_hw(tty->termios, old_termios);
 395         tty_encode_baud_rate(tty, baud, baud);
 396
 397         /*
 398          * send the baud change out on an "empty" data packet
 399          */
 400         urb = usb_alloc_urb(0, GFP_KERNEL);
 401         if (!urb) {
 402                 dev_err(&port->dev, "%s - no more urbs\n", __func__);
 403                 return;
 404         }
 405         transfer_buffer = kmalloc(1, GFP_KERNEL);
 406         if (!transfer_buffer) {
 407                 dev_err(&port->dev, "%s - out of memory\n", __func__);
 408                 goto err_buf;
 409         }
 410
 411         *transfer_buffer = ir_xbof | ir_baud;
 412
 413         usb_fill_bulk_urb(
 414                 urb,
 415                 port->serial->dev,
 416                 usb_sndbulkpipe(port->serial->dev,
 417                         port->bulk_out_endpointAddress),
 418                 transfer_buffer,
 419                 1,
 420                 ir_set_termios_callback,
 421                 port);
 422
 423         urb->transfer_flags = URB_ZERO_PACKET;
 424
 425         result = usb_submit_urb(urb, GFP_KERNEL);
 426         if (result) {
 427                 dev_err(&port->dev, "%s - failed to submit urb: %d\n",
 428                                                         __func__, result);
 429                 goto err_subm;
 430         }
 431
 432         usb_free_urb(urb);
 433
 434         return;
 435 err_subm:
 436         kfree(transfer_buffer);
 437 err_buf:
 438         usb_free_urb(urb);
 439 }
 440
 441 static int __init ir_init(void)
 442 {
 443         int retval;
 444
 445         if (buffer_size) {
 446                 ir_device.bulk_in_size = buffer_size;
 447                 ir_device.bulk_out_size = buffer_size;
 448         }
 449
 450         retval = usb_serial_register_drivers(&ir_driver, serial_drivers);
 451         if (retval == 0)
 452                 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
 453                                DRIVER_DESC "\n");
 454         return retval;
 455 }
 456
 457 static void __exit ir_exit(void)
 458 {
 459         usb_serial_deregister_drivers(&ir_driver, serial_drivers);
 460 }
 461
 462
 463 module_init(ir_init);
 464 module_exit(ir_exit);
 465
 466 MODULE_AUTHOR(DRIVER_AUTHOR);
 467 MODULE_DESCRIPTION(DRIVER_DESC);
 468 MODULE_LICENSE("GPL");
 469
 470 module_param(debug, bool, S_IRUGO | S_IWUSR);
 471 MODULE_PARM_DESC(debug, "Debug enabled or not");
 472 module_param(xbof, int, 0);
 473 MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
 474 module_param(buffer_size, int, 0);
 475 MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
 476