drivers/usb/serial/oti6858.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Ours Technology Inc. OTi-6858 USB to serial adapter driver.
   4  *
   5  * Copyleft  (C) 2007 Kees Lemmens (adapted for kernel 2.6.20)
   6  * Copyright (C) 2006 Tomasz Michal Lukaszewski (FIXME: add e-mail)
   7  * Copyright (C) 2001-2004 Greg Kroah-Hartman ([email protected])
   8  * Copyright (C) 2003 IBM Corp.
   9  *
  10  * Many thanks to the authors of pl2303 driver: all functions in this file
  11  * are heavily based on pl2303 code, buffering code is a 1-to-1 copy.
  12  *
  13  * Warning! You use this driver on your own risk! The only official
  14  * description of this device I have is datasheet from manufacturer,
  15  * and it doesn't contain almost any information needed to write a driver.
  16  * Almost all knowlegde used while writing this driver was gathered by:
  17  *  - analyzing traffic between device and the M$ Windows 2000 driver,
  18  *  - trying different bit combinations and checking pin states
  19  *    with a voltmeter,
  20  *  - receiving malformed frames and producing buffer overflows
  21  *    to learn how errors are reported,
  22  * So, THIS CODE CAN DESTROY OTi-6858 AND ANY OTHER DEVICES, THAT ARE
  23  * CONNECTED TO IT!
  24  *
  25  * See Documentation/usb/usb-serial.rst for more information on using this
  26  * driver
  27  *
  28  * TODO:
  29  *  - implement correct flushing for ioctls and oti6858_close()
  30  *  - check how errors (rx overflow, parity error, framing error) are reported
  31  *  - implement oti6858_break_ctl()
  32  *  - implement more ioctls
  33  *  - test/implement flow control
  34  *  - allow setting custom baud rates
  35  */
  36
  37 #include <linux/kernel.h>
  38 #include <linux/errno.h>
  39 #include <linux/slab.h>
  40 #include <linux/tty.h>
  41 #include <linux/tty_driver.h>
  42 #include <linux/tty_flip.h>
  43 #include <linux/serial.h>
  44 #include <linux/module.h>
  45 #include <linux/moduleparam.h>
  46 #include <linux/spinlock.h>
  47 #include <linux/usb.h>
  48 #include <linux/usb/serial.h>
  49 #include <linux/uaccess.h>
  50 #include <linux/kfifo.h>
  51 #include "oti6858.h"
  52
  53 #define OTI6858_DESCRIPTION \
  54         "Ours Technology Inc. OTi-6858 USB to serial adapter driver"
  55 #define OTI6858_AUTHOR "Tomasz Michal Lukaszewski <FIXME@FIXME>"
  56
  57 static const struct usb_device_id id_table[] = {
  58         { USB_DEVICE(OTI6858_VENDOR_ID, OTI6858_PRODUCT_ID) },
  59         { }
  60 };
  61
  62 MODULE_DEVICE_TABLE(usb, id_table);
  63
  64 /* requests */
  65 #define OTI6858_REQ_GET_STATUS          (USB_DIR_IN | USB_TYPE_VENDOR | 0x00)
  66 #define OTI6858_REQ_T_GET_STATUS        0x01
  67
  68 #define OTI6858_REQ_SET_LINE            (USB_DIR_OUT | USB_TYPE_VENDOR | 0x00)
  69 #define OTI6858_REQ_T_SET_LINE          0x00
  70
  71 #define OTI6858_REQ_CHECK_TXBUFF        (USB_DIR_IN | USB_TYPE_VENDOR | 0x01)
  72 #define OTI6858_REQ_T_CHECK_TXBUFF      0x00
  73
  74 /* format of the control packet */
  75 struct oti6858_control_pkt {
  76         __le16  divisor;        /* baud rate = 96000000 / (16 * divisor), LE */
  77 #define OTI6858_MAX_BAUD_RATE   3000000
  78         u8      frame_fmt;
  79 #define FMT_STOP_BITS_MASK      0xc0
  80 #define FMT_STOP_BITS_1         0x00
  81 #define FMT_STOP_BITS_2         0x40    /* 1.5 stop bits if FMT_DATA_BITS_5 */
  82 #define FMT_PARITY_MASK         0x38
  83 #define FMT_PARITY_NONE         0x00
  84 #define FMT_PARITY_ODD          0x08
  85 #define FMT_PARITY_EVEN         0x18
  86 #define FMT_PARITY_MARK         0x28
  87 #define FMT_PARITY_SPACE        0x38
  88 #define FMT_DATA_BITS_MASK      0x03
  89 #define FMT_DATA_BITS_5         0x00
  90 #define FMT_DATA_BITS_6         0x01
  91 #define FMT_DATA_BITS_7         0x02
  92 #define FMT_DATA_BITS_8         0x03
  93         u8      something;      /* always equals 0x43 */
  94         u8      control;        /* settings of flow control lines */
  95 #define CONTROL_MASK            0x0c
  96 #define CONTROL_DTR_HIGH        0x08
  97 #define CONTROL_RTS_HIGH        0x04
  98         u8      tx_status;
  99 #define TX_BUFFER_EMPTIED       0x09
 100         u8      pin_state;
 101 #define PIN_MASK                0x3f
 102 #define PIN_MSR_MASK            0x1b
 103 #define PIN_RTS                 0x20    /* output pin */
 104 #define PIN_CTS                 0x10    /* input pin, active low */
 105 #define PIN_DSR                 0x08    /* input pin, active low */
 106 #define PIN_DTR                 0x04    /* output pin */
 107 #define PIN_RI                  0x02    /* input pin, active low */
 108 #define PIN_DCD                 0x01    /* input pin, active low */
 109         u8      rx_bytes_avail;         /* number of bytes in rx buffer */;
 110 };
 111
 112 #define OTI6858_CTRL_PKT_SIZE   sizeof(struct oti6858_control_pkt)
 113 #define OTI6858_CTRL_EQUALS_PENDING(a, priv) \
 114         (((a)->divisor == (priv)->pending_setup.divisor) \
 115           && ((a)->control == (priv)->pending_setup.control) \
 116           && ((a)->frame_fmt == (priv)->pending_setup.frame_fmt))
 117
 118 /* function prototypes */
 119 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port);
 120 static void oti6858_close(struct usb_serial_port *port);
 121 static void oti6858_set_termios(struct tty_struct *tty,
 122                                 struct usb_serial_port *port,
 123                                 const struct ktermios *old_termios);
 124 static void oti6858_init_termios(struct tty_struct *tty);
 125 static void oti6858_read_int_callback(struct urb *urb);
 126 static void oti6858_read_bulk_callback(struct urb *urb);
 127 static void oti6858_write_bulk_callback(struct urb *urb);
 128 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 129                         const unsigned char *buf, int count);
 130 static unsigned int oti6858_write_room(struct tty_struct *tty);
 131 static unsigned int oti6858_chars_in_buffer(struct tty_struct *tty);
 132 static int oti6858_tiocmget(struct tty_struct *tty);
 133 static int oti6858_tiocmset(struct tty_struct *tty,
 134                                 unsigned int set, unsigned int clear);
 135 static int oti6858_port_probe(struct usb_serial_port *port);
 136 static void oti6858_port_remove(struct usb_serial_port *port);
 137
 138 /* device info */
 139 static struct usb_serial_driver oti6858_device = {
 140         .driver = {
 141                 .owner =        THIS_MODULE,
 142                 .name =         "oti6858",
 143         },
 144         .id_table =             id_table,
 145         .num_ports =            1,
 146         .num_bulk_in =          1,
 147         .num_bulk_out =         1,
 148         .num_interrupt_in =     1,
 149         .open =                 oti6858_open,
 150         .close =                oti6858_close,
 151         .write =                oti6858_write,
 152         .set_termios =          oti6858_set_termios,
 153         .init_termios =         oti6858_init_termios,
 154         .tiocmget =             oti6858_tiocmget,
 155         .tiocmset =             oti6858_tiocmset,
 156         .tiocmiwait =           usb_serial_generic_tiocmiwait,
 157         .read_bulk_callback =   oti6858_read_bulk_callback,
 158         .read_int_callback =    oti6858_read_int_callback,
 159         .write_bulk_callback =  oti6858_write_bulk_callback,
 160         .write_room =           oti6858_write_room,
 161         .chars_in_buffer =      oti6858_chars_in_buffer,
 162         .port_probe =           oti6858_port_probe,
 163         .port_remove =          oti6858_port_remove,
 164 };
 165
 166 static struct usb_serial_driver * const serial_drivers[] = {
 167         &oti6858_device, NULL
 168 };
 169
 170 struct oti6858_private {
 171         spinlock_t lock;
 172
 173         struct oti6858_control_pkt status;
 174
 175         struct {
 176                 u8 read_urb_in_use;
 177                 u8 write_urb_in_use;
 178         } flags;
 179         struct delayed_work delayed_write_work;
 180
 181         struct {
 182                 __le16 divisor;
 183                 u8 frame_fmt;
 184                 u8 control;
 185         } pending_setup;
 186         u8 transient;
 187         u8 setup_done;
 188         struct delayed_work delayed_setup_work;
 189
 190         struct usb_serial_port *port;   /* USB port with which associated */
 191 };
 192
 193 static void setup_line(struct work_struct *work)
 194 {
 195         struct oti6858_private *priv = container_of(work,
 196                         struct oti6858_private, delayed_setup_work.work);
 197         struct usb_serial_port *port = priv->port;
 198         struct oti6858_control_pkt *new_setup;
 199         unsigned long flags;
 200         int result;
 201
 202         new_setup = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 203         if (!new_setup) {
 204                 /* we will try again */
 205                 schedule_delayed_work(&priv->delayed_setup_work,
 206                                                 msecs_to_jiffies(2));
 207                 return;
 208         }
 209
 210         result = usb_control_msg(port->serial->dev,
 211                                 usb_rcvctrlpipe(port->serial->dev, 0),
 212                                 OTI6858_REQ_T_GET_STATUS,
 213                                 OTI6858_REQ_GET_STATUS,
 214                                 0, 0,
 215                                 new_setup, OTI6858_CTRL_PKT_SIZE,
 216                                 100);
 217
 218         if (result != OTI6858_CTRL_PKT_SIZE) {
 219                 dev_err(&port->dev, "%s(): error reading status\n", __func__);
 220                 kfree(new_setup);
 221                 /* we will try again */
 222                 schedule_delayed_work(&priv->delayed_setup_work,
 223                                                         msecs_to_jiffies(2));
 224                 return;
 225         }
 226
 227         spin_lock_irqsave(&priv->lock, flags);
 228         if (!OTI6858_CTRL_EQUALS_PENDING(new_setup, priv)) {
 229                 new_setup->divisor = priv->pending_setup.divisor;
 230                 new_setup->control = priv->pending_setup.control;
 231                 new_setup->frame_fmt = priv->pending_setup.frame_fmt;
 232
 233                 spin_unlock_irqrestore(&priv->lock, flags);
 234                 result = usb_control_msg(port->serial->dev,
 235                                         usb_sndctrlpipe(port->serial->dev, 0),
 236                                         OTI6858_REQ_T_SET_LINE,
 237                                         OTI6858_REQ_SET_LINE,
 238                                         0, 0,
 239                                         new_setup, OTI6858_CTRL_PKT_SIZE,
 240                                         100);
 241         } else {
 242                 spin_unlock_irqrestore(&priv->lock, flags);
 243                 result = 0;
 244         }
 245         kfree(new_setup);
 246
 247         spin_lock_irqsave(&priv->lock, flags);
 248         if (result != OTI6858_CTRL_PKT_SIZE)
 249                 priv->transient = 0;
 250         priv->setup_done = 1;
 251         spin_unlock_irqrestore(&priv->lock, flags);
 252
 253         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 254         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 255         if (result != 0) {
 256                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 257                         __func__, result);
 258         }
 259 }
 260
 261 static void send_data(struct work_struct *work)
 262 {
 263         struct oti6858_private *priv = container_of(work,
 264                         struct oti6858_private, delayed_write_work.work);
 265         struct usb_serial_port *port = priv->port;
 266         int count = 0, result;
 267         unsigned long flags;
 268         u8 *allow;
 269
 270         spin_lock_irqsave(&priv->lock, flags);
 271         if (priv->flags.write_urb_in_use) {
 272                 spin_unlock_irqrestore(&priv->lock, flags);
 273                 schedule_delayed_work(&priv->delayed_write_work,
 274                                                 msecs_to_jiffies(2));
 275                 return;
 276         }
 277         priv->flags.write_urb_in_use = 1;
 278         spin_unlock_irqrestore(&priv->lock, flags);
 279
 280         spin_lock_irqsave(&port->lock, flags);
 281         count = kfifo_len(&port->write_fifo);
 282         spin_unlock_irqrestore(&port->lock, flags);
 283
 284         if (count > port->bulk_out_size)
 285                 count = port->bulk_out_size;
 286
 287         if (count != 0) {
 288                 allow = kmalloc(1, GFP_KERNEL);
 289                 if (!allow)
 290                         return;
 291
 292                 result = usb_control_msg(port->serial->dev,
 293                                 usb_rcvctrlpipe(port->serial->dev, 0),
 294                                 OTI6858_REQ_T_CHECK_TXBUFF,
 295                                 OTI6858_REQ_CHECK_TXBUFF,
 296                                 count, 0, allow, 1, 100);
 297                 if (result != 1 || *allow != 0)
 298                         count = 0;
 299                 kfree(allow);
 300         }
 301
 302         if (count == 0) {
 303                 priv->flags.write_urb_in_use = 0;
 304
 305                 dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 306                 result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
 307                 if (result != 0) {
 308                         dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 309                                 __func__, result);
 310                 }
 311                 return;
 312         }
 313
 314         count = kfifo_out_locked(&port->write_fifo,
 315                                         port->write_urb->transfer_buffer,
 316                                         count, &port->lock);
 317         port->write_urb->transfer_buffer_length = count;
 318         result = usb_submit_urb(port->write_urb, GFP_NOIO);
 319         if (result != 0) {
 320                 dev_err_console(port, "%s(): usb_submit_urb() failed with error %d\n",
 321                                 __func__, result);
 322                 priv->flags.write_urb_in_use = 0;
 323         }
 324
 325         usb_serial_port_softint(port);
 326 }
 327
 328 static int oti6858_port_probe(struct usb_serial_port *port)
 329 {
 330         struct oti6858_private *priv;
 331
 332         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 333         if (!priv)
 334                 return -ENOMEM;
 335
 336         spin_lock_init(&priv->lock);
 337         priv->port = port;
 338         INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 339         INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 340
 341         usb_set_serial_port_data(port, priv);
 342
 343         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 344
 345         return 0;
 346 }
 347
 348 static void oti6858_port_remove(struct usb_serial_port *port)
 349 {
 350         struct oti6858_private *priv;
 351
 352         priv = usb_get_serial_port_data(port);
 353         kfree(priv);
 354 }
 355
 356 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 357                         const unsigned char *buf, int count)
 358 {
 359         if (!count)
 360                 return count;
 361
 362         count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
 363
 364         return count;
 365 }
 366
 367 static unsigned int oti6858_write_room(struct tty_struct *tty)
 368 {
 369         struct usb_serial_port *port = tty->driver_data;
 370         unsigned int room;
 371         unsigned long flags;
 372
 373         spin_lock_irqsave(&port->lock, flags);
 374         room = kfifo_avail(&port->write_fifo);
 375         spin_unlock_irqrestore(&port->lock, flags);
 376
 377         return room;
 378 }
 379
 380 static unsigned int oti6858_chars_in_buffer(struct tty_struct *tty)
 381 {
 382         struct usb_serial_port *port = tty->driver_data;
 383         unsigned int chars;
 384         unsigned long flags;
 385
 386         spin_lock_irqsave(&port->lock, flags);
 387         chars = kfifo_len(&port->write_fifo);
 388         spin_unlock_irqrestore(&port->lock, flags);
 389
 390         return chars;
 391 }
 392
 393 static void oti6858_init_termios(struct tty_struct *tty)
 394 {
 395         tty_encode_baud_rate(tty, 38400, 38400);
 396 }
 397
 398 static void oti6858_set_termios(struct tty_struct *tty,
 399                                 struct usb_serial_port *port,
 400                                 const struct ktermios *old_termios)
 401 {
 402         struct oti6858_private *priv = usb_get_serial_port_data(port);
 403         unsigned long flags;
 404         unsigned int cflag;
 405         u8 frame_fmt, control;
 406         __le16 divisor;
 407         int br;
 408
 409         cflag = tty->termios.c_cflag;
 410
 411         spin_lock_irqsave(&priv->lock, flags);
 412         frame_fmt = priv->pending_setup.frame_fmt;
 413         control = priv->pending_setup.control;
 414         spin_unlock_irqrestore(&priv->lock, flags);
 415
 416         frame_fmt &= ~FMT_DATA_BITS_MASK;
 417         switch (cflag & CSIZE) {
 418         case CS5:
 419                 frame_fmt |= FMT_DATA_BITS_5;
 420                 break;
 421         case CS6:
 422                 frame_fmt |= FMT_DATA_BITS_6;
 423                 break;
 424         case CS7:
 425                 frame_fmt |= FMT_DATA_BITS_7;
 426                 break;
 427         default:
 428         case CS8:
 429                 frame_fmt |= FMT_DATA_BITS_8;
 430                 break;
 431         }
 432
 433         /* manufacturer claims that this device can work with baud rates
 434          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 435          * guarantee that any other baud rate will work (especially
 436          * the higher ones)
 437          */
 438         br = tty_get_baud_rate(tty);
 439         if (br == 0) {
 440                 divisor = 0;
 441         } else {
 442                 int real_br;
 443                 int new_divisor;
 444                 br = min(br, OTI6858_MAX_BAUD_RATE);
 445
 446                 new_divisor = (96000000 + 8 * br) / (16 * br);
 447                 real_br = 96000000 / (16 * new_divisor);
 448                 divisor = cpu_to_le16(new_divisor);
 449                 tty_encode_baud_rate(tty, real_br, real_br);
 450         }
 451
 452         frame_fmt &= ~FMT_STOP_BITS_MASK;
 453         if ((cflag & CSTOPB) != 0)
 454                 frame_fmt |= FMT_STOP_BITS_2;
 455         else
 456                 frame_fmt |= FMT_STOP_BITS_1;
 457
 458         frame_fmt &= ~FMT_PARITY_MASK;
 459         if ((cflag & PARENB) != 0) {
 460                 if ((cflag & PARODD) != 0)
 461                         frame_fmt |= FMT_PARITY_ODD;
 462                 else
 463                         frame_fmt |= FMT_PARITY_EVEN;
 464         } else {
 465                 frame_fmt |= FMT_PARITY_NONE;
 466         }
 467
 468         control &= ~CONTROL_MASK;
 469         if ((cflag & CRTSCTS) != 0)
 470                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 471
 472         /* change control lines if we are switching to or from B0 */
 473         /* FIXME:
 474         spin_lock_irqsave(&priv->lock, flags);
 475         control = priv->line_control;
 476         if ((cflag & CBAUD) == B0)
 477                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 478         else
 479                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 480         if (control != priv->line_control) {
 481                 control = priv->line_control;
 482                 spin_unlock_irqrestore(&priv->lock, flags);
 483                 set_control_lines(serial->dev, control);
 484         } else {
 485                 spin_unlock_irqrestore(&priv->lock, flags);
 486         }
 487         */
 488
 489         spin_lock_irqsave(&priv->lock, flags);
 490         if (divisor != priv->pending_setup.divisor
 491                         || control != priv->pending_setup.control
 492                         || frame_fmt != priv->pending_setup.frame_fmt) {
 493                 priv->pending_setup.divisor = divisor;
 494                 priv->pending_setup.control = control;
 495                 priv->pending_setup.frame_fmt = frame_fmt;
 496         }
 497         spin_unlock_irqrestore(&priv->lock, flags);
 498 }
 499
 500 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port)
 501 {
 502         struct oti6858_private *priv = usb_get_serial_port_data(port);
 503         struct usb_serial *serial = port->serial;
 504         struct oti6858_control_pkt *buf;
 505         unsigned long flags;
 506         int result;
 507
 508         usb_clear_halt(serial->dev, port->write_urb->pipe);
 509         usb_clear_halt(serial->dev, port->read_urb->pipe);
 510
 511         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 512         if (!buf)
 513                 return -ENOMEM;
 514
 515         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 516                                 OTI6858_REQ_T_GET_STATUS,
 517                                 OTI6858_REQ_GET_STATUS,
 518                                 0, 0,
 519                                 buf, OTI6858_CTRL_PKT_SIZE,
 520                                 100);
 521         if (result != OTI6858_CTRL_PKT_SIZE) {
 522                 /* assume default (after power-on reset) values */
 523                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 524                 buf->frame_fmt = 0x03;  /* 8N1 */
 525                 buf->something = 0x43;
 526                 buf->control = 0x4c;    /* DTR, RTS */
 527                 buf->tx_status = 0x00;
 528                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 529                 buf->rx_bytes_avail = 0x00;
 530         }
 531
 532         spin_lock_irqsave(&priv->lock, flags);
 533         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 534         priv->pending_setup.divisor = buf->divisor;
 535         priv->pending_setup.frame_fmt = buf->frame_fmt;
 536         priv->pending_setup.control = buf->control;
 537         spin_unlock_irqrestore(&priv->lock, flags);
 538         kfree(buf);
 539
 540         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 541         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 542         if (result != 0) {
 543                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 544                         __func__, result);
 545                 oti6858_close(port);
 546                 return result;
 547         }
 548
 549         /* setup termios */
 550         if (tty)
 551                 oti6858_set_termios(tty, port, NULL);
 552
 553         return 0;
 554 }
 555
 556 static void oti6858_close(struct usb_serial_port *port)
 557 {
 558         struct oti6858_private *priv = usb_get_serial_port_data(port);
 559         unsigned long flags;
 560
 561         spin_lock_irqsave(&port->lock, flags);
 562         /* clear out any remaining data in the buffer */
 563         kfifo_reset_out(&port->write_fifo);
 564         spin_unlock_irqrestore(&port->lock, flags);
 565
 566         dev_dbg(&port->dev, "%s(): after buf_clear()\n", __func__);
 567
 568         /* cancel scheduled setup */
 569         cancel_delayed_work_sync(&priv->delayed_setup_work);
 570         cancel_delayed_work_sync(&priv->delayed_write_work);
 571
 572         /* shutdown our urbs */
 573         dev_dbg(&port->dev, "%s(): shutting down urbs\n", __func__);
 574         usb_kill_urb(port->write_urb);
 575         usb_kill_urb(port->read_urb);
 576         usb_kill_urb(port->interrupt_in_urb);
 577 }
 578
 579 static int oti6858_tiocmset(struct tty_struct *tty,
 580                                 unsigned int set, unsigned int clear)
 581 {
 582         struct usb_serial_port *port = tty->driver_data;
 583         struct oti6858_private *priv = usb_get_serial_port_data(port);
 584         unsigned long flags;
 585         u8 control;
 586
 587         dev_dbg(&port->dev, "%s(set = 0x%08x, clear = 0x%08x)\n",
 588                 __func__, set, clear);
 589
 590         /* FIXME: check if this is correct (active high/low) */
 591         spin_lock_irqsave(&priv->lock, flags);
 592         control = priv->pending_setup.control;
 593         if ((set & TIOCM_RTS) != 0)
 594                 control |= CONTROL_RTS_HIGH;
 595         if ((set & TIOCM_DTR) != 0)
 596                 control |= CONTROL_DTR_HIGH;
 597         if ((clear & TIOCM_RTS) != 0)
 598                 control &= ~CONTROL_RTS_HIGH;
 599         if ((clear & TIOCM_DTR) != 0)
 600                 control &= ~CONTROL_DTR_HIGH;
 601
 602         if (control != priv->pending_setup.control)
 603                 priv->pending_setup.control = control;
 604
 605         spin_unlock_irqrestore(&priv->lock, flags);
 606         return 0;
 607 }
 608
 609 static int oti6858_tiocmget(struct tty_struct *tty)
 610 {
 611         struct usb_serial_port *port = tty->driver_data;
 612         struct oti6858_private *priv = usb_get_serial_port_data(port);
 613         unsigned long flags;
 614         unsigned pin_state;
 615         unsigned result = 0;
 616
 617         spin_lock_irqsave(&priv->lock, flags);
 618         pin_state = priv->status.pin_state & PIN_MASK;
 619         spin_unlock_irqrestore(&priv->lock, flags);
 620
 621         /* FIXME: check if this is correct (active high/low) */
 622         if ((pin_state & PIN_RTS) != 0)
 623                 result |= TIOCM_RTS;
 624         if ((pin_state & PIN_CTS) != 0)
 625                 result |= TIOCM_CTS;
 626         if ((pin_state & PIN_DSR) != 0)
 627                 result |= TIOCM_DSR;
 628         if ((pin_state & PIN_DTR) != 0)
 629                 result |= TIOCM_DTR;
 630         if ((pin_state & PIN_RI) != 0)
 631                 result |= TIOCM_RI;
 632         if ((pin_state & PIN_DCD) != 0)
 633                 result |= TIOCM_CD;
 634
 635         dev_dbg(&port->dev, "%s() = 0x%08x\n", __func__, result);
 636
 637         return result;
 638 }
 639
 640 static void oti6858_read_int_callback(struct urb *urb)
 641 {
 642         struct usb_serial_port *port =  urb->context;
 643         struct oti6858_private *priv = usb_get_serial_port_data(port);
 644         int transient = 0, can_recv = 0, resubmit = 1;
 645         int status = urb->status;
 646
 647         switch (status) {
 648         case 0:
 649                 /* success */
 650                 break;
 651         case -ECONNRESET:
 652         case -ENOENT:
 653         case -ESHUTDOWN:
 654                 /* this urb is terminated, clean up */
 655                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n",
 656                         __func__, status);
 657                 return;
 658         default:
 659                 dev_dbg(&urb->dev->dev, "%s(): nonzero urb status received: %d\n",
 660                         __func__, status);
 661                 break;
 662         }
 663
 664         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 665                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 666                 unsigned long flags;
 667
 668                 spin_lock_irqsave(&priv->lock, flags);
 669
 670                 if (!priv->transient) {
 671                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 672                                 if (xs->rx_bytes_avail == 0) {
 673                                         priv->transient = 4;
 674                                         priv->setup_done = 0;
 675                                         resubmit = 0;
 676                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 677                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 678                                 }
 679                         }
 680                 } else {
 681                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 682                                 priv->transient = 0;
 683                         } else if (!priv->setup_done) {
 684                                 resubmit = 0;
 685                         } else if (--priv->transient == 0) {
 686                                 if (xs->rx_bytes_avail == 0) {
 687                                         priv->transient = 4;
 688                                         priv->setup_done = 0;
 689                                         resubmit = 0;
 690                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 691                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 692                                 }
 693                         }
 694                 }
 695
 696                 if (!priv->transient) {
 697                         u8 delta = xs->pin_state ^ priv->status.pin_state;
 698
 699                         if (delta & PIN_MSR_MASK) {
 700                                 if (delta & PIN_CTS)
 701                                         port->icount.cts++;
 702                                 if (delta & PIN_DSR)
 703                                         port->icount.dsr++;
 704                                 if (delta & PIN_RI)
 705                                         port->icount.rng++;
 706                                 if (delta & PIN_DCD)
 707                                         port->icount.dcd++;
 708
 709                                 wake_up_interruptible(&port->port.delta_msr_wait);
 710                         }
 711
 712                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 713                 }
 714
 715                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 716                         can_recv = xs->rx_bytes_avail;
 717                         priv->flags.read_urb_in_use = 1;
 718                 }
 719
 720                 transient = priv->transient;
 721                 spin_unlock_irqrestore(&priv->lock, flags);
 722         }
 723
 724         if (can_recv) {
 725                 int result;
 726
 727                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 728                 if (result != 0) {
 729                         priv->flags.read_urb_in_use = 0;
 730                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 731                                         " error %d\n", __func__, result);
 732                 } else {
 733                         resubmit = 0;
 734                 }
 735         } else if (!transient) {
 736                 unsigned long flags;
 737                 int count;
 738
 739                 spin_lock_irqsave(&port->lock, flags);
 740                 count = kfifo_len(&port->write_fifo);
 741                 spin_unlock_irqrestore(&port->lock, flags);
 742
 743                 spin_lock_irqsave(&priv->lock, flags);
 744                 if (priv->flags.write_urb_in_use == 0 && count != 0) {
 745                         schedule_delayed_work(&priv->delayed_write_work, 0);
 746                         resubmit = 0;
 747                 }
 748                 spin_unlock_irqrestore(&priv->lock, flags);
 749         }
 750
 751         if (resubmit) {
 752                 int result;
 753
 754 /*              dev_dbg(&urb->dev->dev, "%s(): submitting interrupt urb\n", __func__); */
 755                 result = usb_submit_urb(urb, GFP_ATOMIC);
 756                 if (result != 0) {
 757                         dev_err(&urb->dev->dev,
 758                                         "%s(): usb_submit_urb() failed with"
 759                                         " error %d\n", __func__, result);
 760                 }
 761         }
 762 }
 763
 764 static void oti6858_read_bulk_callback(struct urb *urb)
 765 {
 766         struct usb_serial_port *port =  urb->context;
 767         struct oti6858_private *priv = usb_get_serial_port_data(port);
 768         unsigned char *data = urb->transfer_buffer;
 769         unsigned long flags;
 770         int status = urb->status;
 771         int result;
 772
 773         spin_lock_irqsave(&priv->lock, flags);
 774         priv->flags.read_urb_in_use = 0;
 775         spin_unlock_irqrestore(&priv->lock, flags);
 776
 777         if (status != 0) {
 778                 dev_dbg(&urb->dev->dev, "%s(): unable to handle the error, exiting\n", __func__);
 779                 return;
 780         }
 781
 782         if (urb->actual_length > 0) {
 783                 tty_insert_flip_string(&port->port, data, urb->actual_length);
 784                 tty_flip_buffer_push(&port->port);
 785         }
 786
 787         /* schedule the interrupt urb */
 788         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 789         if (result != 0 && result != -EPERM) {
 790                 dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 791                                 " error %d\n", __func__, result);
 792         }
 793 }
 794
 795 static void oti6858_write_bulk_callback(struct urb *urb)
 796 {
 797         struct usb_serial_port *port =  urb->context;
 798         struct oti6858_private *priv = usb_get_serial_port_data(port);
 799         int status = urb->status;
 800         int result;
 801
 802         switch (status) {
 803         case 0:
 804                 /* success */
 805                 break;
 806         case -ECONNRESET:
 807         case -ENOENT:
 808         case -ESHUTDOWN:
 809                 /* this urb is terminated, clean up */
 810                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n", __func__, status);
 811                 priv->flags.write_urb_in_use = 0;
 812                 return;
 813         default:
 814                 /* error in the urb, so we have to resubmit it */
 815                 dev_dbg(&urb->dev->dev, "%s(): nonzero write bulk status received: %d\n", __func__, status);
 816                 dev_dbg(&urb->dev->dev, "%s(): overflow in write\n", __func__);
 817
 818                 port->write_urb->transfer_buffer_length = 1;
 819                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 820                 if (result) {
 821                         dev_err_console(port, "%s(): usb_submit_urb() failed,"
 822                                         " error %d\n", __func__, result);
 823                 } else {
 824                         return;
 825                 }
 826         }
 827
 828         priv->flags.write_urb_in_use = 0;
 829
 830         /* schedule the interrupt urb if we are still open */
 831         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 832         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 833         if (result != 0) {
 834                 dev_err(&port->dev, "%s(): failed submitting int urb,"
 835                                         " error %d\n", __func__, result);
 836         }
 837 }
 838
 839 module_usb_serial_driver(serial_drivers, id_table);
 840
 841 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
 842 MODULE_AUTHOR(OTI6858_AUTHOR);
 843 MODULE_LICENSE("GPL v2");