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         .disconnect     = usb_serial_disconnect,
  83         .id_table       = ir_id_table,
  84 };
  85
  86 static struct usb_serial_driver ir_device = {
  87         .driver = {
  88                 .owner  = THIS_MODULE,
  89                 .name   = "ir-usb",
  90         },
  91         .description            = "IR Dongle",
  92         .id_table               = ir_id_table,
  93         .num_ports              = 1,
  94         .set_termios            = ir_set_termios,
  95         .attach                 = ir_startup,
  96         .open                   = ir_open,
  97         .prepare_write_buffer   = ir_prepare_write_buffer,
  98         .process_read_urb       = ir_process_read_urb,
  99 };
 100
 101 static struct usb_serial_driver * const serial_drivers[] = {
 102         &ir_device, NULL
 103 };
 104
 105 static inline void irda_usb_dump_class_desc(struct usb_irda_cs_descriptor *desc)
 106 {
 107         dbg("bLength=%x", desc->bLength);
 108         dbg("bDescriptorType=%x", desc->bDescriptorType);
 109         dbg("bcdSpecRevision=%x", __le16_to_cpu(desc->bcdSpecRevision));
 110         dbg("bmDataSize=%x", desc->bmDataSize);
 111         dbg("bmWindowSize=%x", desc->bmWindowSize);
 112         dbg("bmMinTurnaroundTime=%d", desc->bmMinTurnaroundTime);
 113         dbg("wBaudRate=%x", __le16_to_cpu(desc->wBaudRate));
 114         dbg("bmAdditionalBOFs=%x", desc->bmAdditionalBOFs);
 115         dbg("bIrdaRateSniff=%x", desc->bIrdaRateSniff);
 116         dbg("bMaxUnicastList=%x", desc->bMaxUnicastList);
 117 }
 118
 119 /*------------------------------------------------------------------*/
 120 /*
 121  * Function irda_usb_find_class_desc(dev, ifnum)
 122  *
 123  *    Returns instance of IrDA class descriptor, or NULL if not found
 124  *
 125  * The class descriptor is some extra info that IrDA USB devices will
 126  * offer to us, describing their IrDA characteristics. We will use that in
 127  * irda_usb_init_qos()
 128  *
 129  * Based on the same function in drivers/net/irda/irda-usb.c
 130  */
 131 static struct usb_irda_cs_descriptor *
 132 irda_usb_find_class_desc(struct usb_device *dev, unsigned int ifnum)
 133 {
 134         struct usb_irda_cs_descriptor *desc;
 135         int ret;
 136
 137         desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 138         if (!desc)
 139                 return NULL;
 140
 141         ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 142                         USB_REQ_CS_IRDA_GET_CLASS_DESC,
 143                         USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 144                         0, ifnum, desc, sizeof(*desc), 1000);
 145
 146         dbg("%s -  ret=%d", __func__, ret);
 147         if (ret < sizeof(*desc)) {
 148                 dbg("%s - class descriptor read %s (%d)",
 149                                 __func__,
 150                                 (ret < 0) ? "failed" : "too short",
 151                                 ret);
 152                 goto error;
 153         }
 154         if (desc->bDescriptorType != USB_DT_CS_IRDA) {
 155                 dbg("%s - bad class descriptor type", __func__);
 156                 goto error;
 157         }
 158
 159         irda_usb_dump_class_desc(desc);
 160         return desc;
 161
 162 error:
 163         kfree(desc);
 164         return NULL;
 165 }
 166
 167 static u8 ir_xbof_change(u8 xbof)
 168 {
 169         u8 result;
 170
 171         /* reference irda-usb.c */
 172         switch (xbof) {
 173         case 48:
 174                 result = 0x10;
 175                 break;
 176         case 28:
 177         case 24:
 178                 result = 0x20;
 179                 break;
 180         default:
 181         case 12:
 182                 result = 0x30;
 183                 break;
 184         case  5:
 185         case  6:
 186                 result = 0x40;
 187                 break;
 188         case  3:
 189                 result = 0x50;
 190                 break;
 191         case  2:
 192                 result = 0x60;
 193                 break;
 194         case  1:
 195                 result = 0x70;
 196                 break;
 197         case  0:
 198                 result = 0x80;
 199                 break;
 200         }
 201
 202         return(result);
 203 }
 204
 205 static int ir_startup(struct usb_serial *serial)
 206 {
 207         struct usb_irda_cs_descriptor *irda_desc;
 208
 209         irda_desc = irda_usb_find_class_desc(serial->dev, 0);
 210         if (!irda_desc) {
 211                 dev_err(&serial->dev->dev,
 212                         "IRDA class descriptor not found, device not bound\n");
 213                 return -ENODEV;
 214         }
 215
 216         dbg("%s - Baud rates supported:%s%s%s%s%s%s%s%s%s",
 217                 __func__,
 218                 (irda_desc->wBaudRate & USB_IRDA_BR_2400) ? " 2400" : "",
 219                 (irda_desc->wBaudRate & USB_IRDA_BR_9600) ? " 9600" : "",
 220                 (irda_desc->wBaudRate & USB_IRDA_BR_19200) ? " 19200" : "",
 221                 (irda_desc->wBaudRate & USB_IRDA_BR_38400) ? " 38400" : "",
 222                 (irda_desc->wBaudRate & USB_IRDA_BR_57600) ? " 57600" : "",
 223                 (irda_desc->wBaudRate & USB_IRDA_BR_115200) ? " 115200" : "",
 224                 (irda_desc->wBaudRate & USB_IRDA_BR_576000) ? " 576000" : "",
 225                 (irda_desc->wBaudRate & USB_IRDA_BR_1152000) ? " 1152000" : "",
 226                 (irda_desc->wBaudRate & USB_IRDA_BR_4000000) ? " 4000000" : "");
 227
 228         switch (irda_desc->bmAdditionalBOFs) {
 229         case USB_IRDA_AB_48:
 230                 ir_add_bof = 48;
 231                 break;
 232         case USB_IRDA_AB_24:
 233                 ir_add_bof = 24;
 234                 break;
 235         case USB_IRDA_AB_12:
 236                 ir_add_bof = 12;
 237                 break;
 238         case USB_IRDA_AB_6:
 239                 ir_add_bof = 6;
 240                 break;
 241         case USB_IRDA_AB_3:
 242                 ir_add_bof = 3;
 243                 break;
 244         case USB_IRDA_AB_2:
 245                 ir_add_bof = 2;
 246                 break;
 247         case USB_IRDA_AB_1:
 248                 ir_add_bof = 1;
 249                 break;
 250         case USB_IRDA_AB_0:
 251                 ir_add_bof = 0;
 252                 break;
 253         default:
 254                 break;
 255         }
 256
 257         kfree(irda_desc);
 258
 259         return 0;
 260 }
 261
 262 static int ir_open(struct tty_struct *tty, struct usb_serial_port *port)
 263 {
 264         int i;
 265
 266         for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 267                 port->write_urbs[i]->transfer_flags = URB_ZERO_PACKET;
 268
 269         /* Start reading from the device */
 270         return usb_serial_generic_open(tty, port);
 271 }
 272
 273 static int ir_prepare_write_buffer(struct usb_serial_port *port,
 274                                                 void *dest, size_t size)
 275 {
 276         unsigned char *buf = dest;
 277         int count;
 278
 279         /*
 280          * The first byte of the packet we send to the device contains an
 281          * inbound header which indicates an additional number of BOFs and
 282          * a baud rate change.
 283          *
 284          * See section 5.4.2.2 of the USB IrDA spec.
 285          */
 286         *buf = ir_xbof | ir_baud;
 287
 288         count = kfifo_out_locked(&port->write_fifo, buf + 1, size - 1,
 289                                                                 &port->lock);
 290         return count + 1;
 291 }
 292
 293 static void ir_process_read_urb(struct urb *urb)
 294 {
 295         struct usb_serial_port *port = urb->context;
 296         unsigned char *data = urb->transfer_buffer;
 297         struct tty_struct *tty;
 298
 299         if (!urb->actual_length)
 300                 return;
 301         /*
 302          * The first byte of the packet we get from the device
 303          * contains a busy indicator and baud rate change.
 304          * See section 5.4.1.2 of the USB IrDA spec.
 305          */
 306         if (*data & 0x0f)
 307                 ir_baud = *data & 0x0f;
 308
 309         if (urb->actual_length == 1)
 310                 return;
 311
 312         tty = tty_port_tty_get(&port->port);
 313         if (!tty)
 314                 return;
 315         tty_insert_flip_string(tty, data + 1, urb->actual_length - 1);
 316         tty_flip_buffer_push(tty);
 317         tty_kref_put(tty);
 318 }
 319
 320 static void ir_set_termios_callback(struct urb *urb)
 321 {
 322         kfree(urb->transfer_buffer);
 323
 324         if (urb->status)
 325                 dbg("%s - non-zero urb status: %d", __func__, urb->status);
 326 }
 327
 328 static void ir_set_termios(struct tty_struct *tty,
 329                 struct usb_serial_port *port, struct ktermios *old_termios)
 330 {
 331         struct urb *urb;
 332         unsigned char *transfer_buffer;
 333         int result;
 334         speed_t baud;
 335         int ir_baud;
 336
 337         baud = tty_get_baud_rate(tty);
 338
 339         /*
 340          * FIXME, we should compare the baud request against the
 341          * capability stated in the IR header that we got in the
 342          * startup function.
 343          */
 344
 345         switch (baud) {
 346         case 2400:
 347                 ir_baud = USB_IRDA_BR_2400;
 348                 break;
 349         case 9600:
 350                 ir_baud = USB_IRDA_BR_9600;
 351                 break;
 352         case 19200:
 353                 ir_baud = USB_IRDA_BR_19200;
 354                 break;
 355         case 38400:
 356                 ir_baud = USB_IRDA_BR_38400;
 357                 break;
 358         case 57600:
 359                 ir_baud = USB_IRDA_BR_57600;
 360                 break;
 361         case 115200:
 362                 ir_baud = USB_IRDA_BR_115200;
 363                 break;
 364         case 576000:
 365                 ir_baud = USB_IRDA_BR_576000;
 366                 break;
 367         case 1152000:
 368                 ir_baud = USB_IRDA_BR_1152000;
 369                 break;
 370         case 4000000:
 371                 ir_baud = USB_IRDA_BR_4000000;
 372                 break;
 373         default:
 374                 ir_baud = USB_IRDA_BR_9600;
 375                 baud = 9600;
 376         }
 377
 378         if (xbof == -1)
 379                 ir_xbof = ir_xbof_change(ir_add_bof);
 380         else
 381                 ir_xbof = ir_xbof_change(xbof) ;
 382
 383         /* Only speed changes are supported */
 384         tty_termios_copy_hw(tty->termios, old_termios);
 385         tty_encode_baud_rate(tty, baud, baud);
 386
 387         /*
 388          * send the baud change out on an "empty" data packet
 389          */
 390         urb = usb_alloc_urb(0, GFP_KERNEL);
 391         if (!urb) {
 392                 dev_err(&port->dev, "%s - no more urbs\n", __func__);
 393                 return;
 394         }
 395         transfer_buffer = kmalloc(1, GFP_KERNEL);
 396         if (!transfer_buffer) {
 397                 dev_err(&port->dev, "%s - out of memory\n", __func__);
 398                 goto err_buf;
 399         }
 400
 401         *transfer_buffer = ir_xbof | ir_baud;
 402
 403         usb_fill_bulk_urb(
 404                 urb,
 405                 port->serial->dev,
 406                 usb_sndbulkpipe(port->serial->dev,
 407                         port->bulk_out_endpointAddress),
 408                 transfer_buffer,
 409                 1,
 410                 ir_set_termios_callback,
 411                 port);
 412
 413         urb->transfer_flags = URB_ZERO_PACKET;
 414
 415         result = usb_submit_urb(urb, GFP_KERNEL);
 416         if (result) {
 417                 dev_err(&port->dev, "%s - failed to submit urb: %d\n",
 418                                                         __func__, result);
 419                 goto err_subm;
 420         }
 421
 422         usb_free_urb(urb);
 423
 424         return;
 425 err_subm:
 426         kfree(transfer_buffer);
 427 err_buf:
 428         usb_free_urb(urb);
 429 }
 430
 431 static int __init ir_init(void)
 432 {
 433         int retval;
 434
 435         if (buffer_size) {
 436                 ir_device.bulk_in_size = buffer_size;
 437                 ir_device.bulk_out_size = buffer_size;
 438         }
 439
 440         retval = usb_serial_register_drivers(&ir_driver, serial_drivers);
 441         if (retval == 0)
 442                 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
 443                                DRIVER_DESC "\n");
 444         return retval;
 445 }
 446
 447 static void __exit ir_exit(void)
 448 {
 449         usb_serial_deregister_drivers(&ir_driver, serial_drivers);
 450 }
 451
 452
 453 module_init(ir_init);
 454 module_exit(ir_exit);
 455
 456 MODULE_AUTHOR(DRIVER_AUTHOR);
 457 MODULE_DESCRIPTION(DRIVER_DESC);
 458 MODULE_LICENSE("GPL");
 459
 460 module_param(debug, bool, S_IRUGO | S_IWUSR);
 461 MODULE_PARM_DESC(debug, "Debug enabled or not");
 462 module_param(xbof, int, 0);
 463 MODULE_PARM_DESC(xbof, "Force specific number of XBOFs");
 464 module_param(buffer_size, int, 0);
 465 MODULE_PARM_DESC(buffer_size, "Size of the transfer buffers");
 466