drivers/usb/serial/cypress_m8.c

   1 /*
   2  * USB Cypress M8 driver
   3  *
   4  *      Copyright (C) 2004
   5  *          Lonnie Mendez (dignome@gmail.com)
   6  *      Copyright (C) 2003,2004
   7  *          Neil Whelchel (koyama@firstlight.net)
   8  *
   9  *      This program is free software; you can redistribute it and/or modify
  10  *      it under the terms of the GNU General Public License as published by
  11  *      the Free Software Foundation; either version 2 of the License, or
  12  *      (at your option) any later version.
  13  *
  14  * See Documentation/usb/usb-serial.txt for more information on using this
  15  * driver
  16  *
  17  * See http://geocities.com/i0xox0i for information on this driver and the
  18  * earthmate usb device.
  19  */
  20
  21 /* Thanks to Neil Whelchel for writing the first cypress m8 implementation
  22    for linux. */
  23 /* Thanks to cypress for providing references for the hid reports. */
  24 /* Thanks to Jiang Zhang for providing links and for general help. */
  25 /* Code originates and was built up from ftdi_sio, belkin, pl2303 and others.*/
  26
  27
  28 #include <linux/kernel.h>
  29 #include <linux/errno.h>
  30 #include <linux/init.h>
  31 #include <linux/slab.h>
  32 #include <linux/tty.h>
  33 #include <linux/tty_driver.h>
  34 #include <linux/tty_flip.h>
  35 #include <linux/module.h>
  36 #include <linux/moduleparam.h>
  37 #include <linux/spinlock.h>
  38 #include <linux/usb.h>
  39 #include <linux/usb/serial.h>
  40 #include <linux/serial.h>
  41 #include <linux/kfifo.h>
  42 #include <linux/delay.h>
  43 #include <linux/uaccess.h>
  44 #include <asm/unaligned.h>
  45
  46 #include "cypress_m8.h"
  47
  48
  49 static bool debug;
  50 static bool stats;
  51 static int interval;
  52 static bool unstable_bauds;
  53
  54 /*
  55  * Version Information
  56  */
  57 #define DRIVER_VERSION "v1.10"
  58 #define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
  59 #define DRIVER_DESC "Cypress USB to Serial Driver"
  60
  61 /* write buffer size defines */
  62 #define CYPRESS_BUF_SIZE        1024
  63
  64 static const struct usb_device_id id_table_earthmate[] = {
  65         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  66         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  67         { }                                             /* Terminating entry */
  68 };
  69
  70 static const struct usb_device_id id_table_cyphidcomrs232[] = {
  71         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  72         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  73         { }                                             /* Terminating entry */
  74 };
  75
  76 static const struct usb_device_id id_table_nokiaca42v2[] = {
  77         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  78         { }                                             /* Terminating entry */
  79 };
  80
  81 static const struct usb_device_id id_table_combined[] = {
  82         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  83         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  84         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  85         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  86         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  87         { }                                             /* Terminating entry */
  88 };
  89
  90 MODULE_DEVICE_TABLE(usb, id_table_combined);
  91
  92 enum packet_format {
  93         packet_format_1,  /* b0:status, b1:payload count */
  94         packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
  95 };
  96
  97 struct cypress_private {
  98         spinlock_t lock;                   /* private lock */
  99         int chiptype;                      /* identifier of device, for quirks/etc */
 100         int bytes_in;                      /* used for statistics */
 101         int bytes_out;                     /* used for statistics */
 102         int cmd_count;                     /* used for statistics */
 103         int cmd_ctrl;                      /* always set this to 1 before issuing a command */
 104         struct kfifo write_fifo;           /* write fifo */
 105         int write_urb_in_use;              /* write urb in use indicator */
 106         int write_urb_interval;            /* interval to use for write urb */
 107         int read_urb_interval;             /* interval to use for read urb */
 108         int comm_is_ok;                    /* true if communication is (still) ok */
 109         int termios_initialized;
 110         __u8 line_control;                 /* holds dtr / rts value */
 111         __u8 current_status;               /* received from last read - info on dsr,cts,cd,ri,etc */
 112         __u8 current_config;               /* stores the current configuration byte */
 113         __u8 rx_flags;                     /* throttling - used from whiteheat/ftdi_sio */
 114         enum packet_format pkt_fmt;        /* format to use for packet send / receive */
 115         int get_cfg_unsafe;                /* If true, the CYPRESS_GET_CONFIG is unsafe */
 116         int baud_rate;                     /* stores current baud rate in
 117                                               integer form */
 118         int isthrottled;                   /* if throttled, discard reads */
 119         wait_queue_head_t delta_msr_wait;  /* used for TIOCMIWAIT */
 120         char prev_status, diff_status;     /* used for TIOCMIWAIT */
 121         /* we pass a pointer to this as the argument sent to
 122            cypress_set_termios old_termios */
 123         struct ktermios tmp_termios;       /* stores the old termios settings */
 124 };
 125
 126 /* function prototypes for the Cypress USB to serial device */
 127 static int  cypress_earthmate_startup(struct usb_serial *serial);
 128 static int  cypress_hidcom_startup(struct usb_serial *serial);
 129 static int  cypress_ca42v2_startup(struct usb_serial *serial);
 130 static void cypress_release(struct usb_serial *serial);
 131 static int  cypress_open(struct tty_struct *tty, struct usb_serial_port *port);
 132 static void cypress_close(struct usb_serial_port *port);
 133 static void cypress_dtr_rts(struct usb_serial_port *port, int on);
 134 static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 135                         const unsigned char *buf, int count);
 136 static void cypress_send(struct usb_serial_port *port);
 137 static int  cypress_write_room(struct tty_struct *tty);
 138 static int  cypress_ioctl(struct tty_struct *tty,
 139                         unsigned int cmd, unsigned long arg);
 140 static void cypress_set_termios(struct tty_struct *tty,
 141                         struct usb_serial_port *port, struct ktermios *old);
 142 static int  cypress_tiocmget(struct tty_struct *tty);
 143 static int  cypress_tiocmset(struct tty_struct *tty,
 144                         unsigned int set, unsigned int clear);
 145 static int  cypress_chars_in_buffer(struct tty_struct *tty);
 146 static void cypress_throttle(struct tty_struct *tty);
 147 static void cypress_unthrottle(struct tty_struct *tty);
 148 static void cypress_set_dead(struct usb_serial_port *port);
 149 static void cypress_read_int_callback(struct urb *urb);
 150 static void cypress_write_int_callback(struct urb *urb);
 151
 152 static struct usb_serial_driver cypress_earthmate_device = {
 153         .driver = {
 154                 .owner =                THIS_MODULE,
 155                 .name =                 "earthmate",
 156         },
 157         .description =                  "DeLorme Earthmate USB",
 158         .id_table =                     id_table_earthmate,
 159         .num_ports =                    1,
 160         .attach =                       cypress_earthmate_startup,
 161         .release =                      cypress_release,
 162         .open =                         cypress_open,
 163         .close =                        cypress_close,
 164         .dtr_rts =                      cypress_dtr_rts,
 165         .write =                        cypress_write,
 166         .write_room =                   cypress_write_room,
 167         .ioctl =                        cypress_ioctl,
 168         .set_termios =                  cypress_set_termios,
 169         .tiocmget =                     cypress_tiocmget,
 170         .tiocmset =                     cypress_tiocmset,
 171         .chars_in_buffer =              cypress_chars_in_buffer,
 172         .throttle =                     cypress_throttle,
 173         .unthrottle =                   cypress_unthrottle,
 174         .read_int_callback =            cypress_read_int_callback,
 175         .write_int_callback =           cypress_write_int_callback,
 176 };
 177
 178 static struct usb_serial_driver cypress_hidcom_device = {
 179         .driver = {
 180                 .owner =                THIS_MODULE,
 181                 .name =                 "cyphidcom",
 182         },
 183         .description =                  "HID->COM RS232 Adapter",
 184         .id_table =                     id_table_cyphidcomrs232,
 185         .num_ports =                    1,
 186         .attach =                       cypress_hidcom_startup,
 187         .release =                      cypress_release,
 188         .open =                         cypress_open,
 189         .close =                        cypress_close,
 190         .dtr_rts =                      cypress_dtr_rts,
 191         .write =                        cypress_write,
 192         .write_room =                   cypress_write_room,
 193         .ioctl =                        cypress_ioctl,
 194         .set_termios =                  cypress_set_termios,
 195         .tiocmget =                     cypress_tiocmget,
 196         .tiocmset =                     cypress_tiocmset,
 197         .chars_in_buffer =              cypress_chars_in_buffer,
 198         .throttle =                     cypress_throttle,
 199         .unthrottle =                   cypress_unthrottle,
 200         .read_int_callback =            cypress_read_int_callback,
 201         .write_int_callback =           cypress_write_int_callback,
 202 };
 203
 204 static struct usb_serial_driver cypress_ca42v2_device = {
 205         .driver = {
 206                 .owner =                THIS_MODULE,
 207                 .name =                 "nokiaca42v2",
 208         },
 209         .description =                  "Nokia CA-42 V2 Adapter",
 210         .id_table =                     id_table_nokiaca42v2,
 211         .num_ports =                    1,
 212         .attach =                       cypress_ca42v2_startup,
 213         .release =                      cypress_release,
 214         .open =                         cypress_open,
 215         .close =                        cypress_close,
 216         .dtr_rts =                      cypress_dtr_rts,
 217         .write =                        cypress_write,
 218         .write_room =                   cypress_write_room,
 219         .ioctl =                        cypress_ioctl,
 220         .set_termios =                  cypress_set_termios,
 221         .tiocmget =                     cypress_tiocmget,
 222         .tiocmset =                     cypress_tiocmset,
 223         .chars_in_buffer =              cypress_chars_in_buffer,
 224         .throttle =                     cypress_throttle,
 225         .unthrottle =                   cypress_unthrottle,
 226         .read_int_callback =            cypress_read_int_callback,
 227         .write_int_callback =           cypress_write_int_callback,
 228 };
 229
 230 static struct usb_serial_driver * const serial_drivers[] = {
 231         &cypress_earthmate_device, &cypress_hidcom_device,
 232         &cypress_ca42v2_device, NULL
 233 };
 234
 235 /*****************************************************************************
 236  * Cypress serial helper functions
 237  *****************************************************************************/
 238
 239
 240 static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
 241 {
 242         struct cypress_private *priv;
 243         priv = usb_get_serial_port_data(port);
 244
 245         if (unstable_bauds)
 246                 return new_rate;
 247
 248         /*
 249          * The general purpose firmware for the Cypress M8 allows for
 250          * a maximum speed of 57600bps (I have no idea whether DeLorme
 251          * chose to use the general purpose firmware or not), if you
 252          * need to modify this speed setting for your own project
 253          * please add your own chiptype and modify the code likewise.
 254          * The Cypress HID->COM device will work successfully up to
 255          * 115200bps (but the actual throughput is around 3kBps).
 256          */
 257         if (port->serial->dev->speed == USB_SPEED_LOW) {
 258                 /*
 259                  * Mike Isely <isely@pobox.com> 2-Feb-2008: The
 260                  * Cypress app note that describes this mechanism
 261                  * states the the low-speed part can't handle more
 262                  * than 800 bytes/sec, in which case 4800 baud is the
 263                  * safest speed for a part like that.
 264                  */
 265                 if (new_rate > 4800) {
 266                         dbg("%s - failed setting baud rate, device incapable "
 267                             "speed %d", __func__, new_rate);
 268                         return -1;
 269                 }
 270         }
 271         switch (priv->chiptype) {
 272         case CT_EARTHMATE:
 273                 if (new_rate <= 600) {
 274                         /* 300 and 600 baud rates are supported under
 275                          * the generic firmware, but are not used with
 276                          * NMEA and SiRF protocols */
 277                         dbg("%s - failed setting baud rate, unsupported speed "
 278                             "of %d on Earthmate GPS", __func__, new_rate);
 279                         return -1;
 280                 }
 281                 break;
 282         default:
 283                 break;
 284         }
 285         return new_rate;
 286 }
 287
 288
 289 /* This function can either set or retrieve the current serial line settings */
 290 static int cypress_serial_control(struct tty_struct *tty,
 291         struct usb_serial_port *port, speed_t baud_rate, int data_bits,
 292         int stop_bits, int parity_enable, int parity_type, int reset,
 293         int cypress_request_type)
 294 {
 295         int new_baudrate = 0, retval = 0, tries = 0;
 296         struct cypress_private *priv;
 297         u8 *feature_buffer;
 298         const unsigned int feature_len = 5;
 299         unsigned long flags;
 300
 301         priv = usb_get_serial_port_data(port);
 302
 303         if (!priv->comm_is_ok)
 304                 return -ENODEV;
 305
 306         feature_buffer = kcalloc(feature_len, sizeof(u8), GFP_KERNEL);
 307         if (!feature_buffer)
 308                 return -ENOMEM;
 309
 310         switch (cypress_request_type) {
 311         case CYPRESS_SET_CONFIG:
 312                 /* 0 means 'Hang up' so doesn't change the true bit rate */
 313                 new_baudrate = priv->baud_rate;
 314                 if (baud_rate && baud_rate != priv->baud_rate) {
 315                         dbg("%s - baud rate is changing", __func__);
 316                         retval = analyze_baud_rate(port, baud_rate);
 317                         if (retval >= 0) {
 318                                 new_baudrate = retval;
 319                                 dbg("%s - New baud rate set to %d",
 320                                     __func__, new_baudrate);
 321                         }
 322                 }
 323                 dbg("%s - baud rate is being sent as %d",
 324                                         __func__, new_baudrate);
 325
 326                 /* fill the feature_buffer with new configuration */
 327                 put_unaligned_le32(new_baudrate, feature_buffer);
 328                 feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
 329                 /* 1 bit gap */
 330                 feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
 331                 feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
 332                 feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
 333                 /* 1 bit gap */
 334                 feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
 335
 336                 dbg("%s - device is being sent this feature report:",
 337                                                                 __func__);
 338                 dbg("%s - %02X - %02X - %02X - %02X - %02X", __func__,
 339                         feature_buffer[0], feature_buffer[1],
 340                         feature_buffer[2], feature_buffer[3],
 341                         feature_buffer[4]);
 342
 343                 do {
 344                         retval = usb_control_msg(port->serial->dev,
 345                                         usb_sndctrlpipe(port->serial->dev, 0),
 346                                         HID_REQ_SET_REPORT,
 347                                         USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 348                                         0x0300, 0, feature_buffer,
 349                                         feature_len, 500);
 350
 351                         if (tries++ >= 3)
 352                                 break;
 353
 354                 } while (retval != feature_len &&
 355                          retval != -ENODEV);
 356
 357                 if (retval != feature_len) {
 358                         dev_err(&port->dev, "%s - failed sending serial "
 359                                 "line settings - %d\n", __func__, retval);
 360                         cypress_set_dead(port);
 361                 } else {
 362                         spin_lock_irqsave(&priv->lock, flags);
 363                         priv->baud_rate = new_baudrate;
 364                         priv->current_config = feature_buffer[4];
 365                         spin_unlock_irqrestore(&priv->lock, flags);
 366                         /* If we asked for a speed change encode it */
 367                         if (baud_rate)
 368                                 tty_encode_baud_rate(tty,
 369                                         new_baudrate, new_baudrate);
 370                 }
 371         break;
 372         case CYPRESS_GET_CONFIG:
 373                 if (priv->get_cfg_unsafe) {
 374                         /* Not implemented for this device,
 375                            and if we try to do it we're likely
 376                            to crash the hardware. */
 377                         retval = -ENOTTY;
 378                         goto out;
 379                 }
 380                 dbg("%s - retreiving serial line settings", __func__);
 381                 do {
 382                         retval = usb_control_msg(port->serial->dev,
 383                                         usb_rcvctrlpipe(port->serial->dev, 0),
 384                                         HID_REQ_GET_REPORT,
 385                                         USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 386                                         0x0300, 0, feature_buffer,
 387                                         feature_len, 500);
 388
 389                         if (tries++ >= 3)
 390                                 break;
 391                 } while (retval != feature_len
 392                                                 && retval != -ENODEV);
 393
 394                 if (retval != feature_len) {
 395                         dev_err(&port->dev, "%s - failed to retrieve serial "
 396                                 "line settings - %d\n", __func__, retval);
 397                         cypress_set_dead(port);
 398                         goto out;
 399                 } else {
 400                         spin_lock_irqsave(&priv->lock, flags);
 401                         /* store the config in one byte, and later
 402                            use bit masks to check values */
 403                         priv->current_config = feature_buffer[4];
 404                         priv->baud_rate = get_unaligned_le32(feature_buffer);
 405                         spin_unlock_irqrestore(&priv->lock, flags);
 406                 }
 407         }
 408         spin_lock_irqsave(&priv->lock, flags);
 409         ++priv->cmd_count;
 410         spin_unlock_irqrestore(&priv->lock, flags);
 411 out:
 412         kfree(feature_buffer);
 413         return retval;
 414 } /* cypress_serial_control */
 415
 416
 417 static void cypress_set_dead(struct usb_serial_port *port)
 418 {
 419         struct cypress_private *priv = usb_get_serial_port_data(port);
 420         unsigned long flags;
 421
 422         spin_lock_irqsave(&priv->lock, flags);
 423         if (!priv->comm_is_ok) {
 424                 spin_unlock_irqrestore(&priv->lock, flags);
 425                 return;
 426         }
 427         priv->comm_is_ok = 0;
 428         spin_unlock_irqrestore(&priv->lock, flags);
 429
 430         dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
 431                 "interval might be too short\n", port->number);
 432 }
 433
 434
 435 /*****************************************************************************
 436  * Cypress serial driver functions
 437  *****************************************************************************/
 438
 439
 440 static int generic_startup(struct usb_serial *serial)
 441 {
 442         struct cypress_private *priv;
 443         struct usb_serial_port *port = serial->port[0];
 444
 445         priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
 446         if (!priv)
 447                 return -ENOMEM;
 448
 449         priv->comm_is_ok = !0;
 450         spin_lock_init(&priv->lock);
 451         if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
 452                 kfree(priv);
 453                 return -ENOMEM;
 454         }
 455         init_waitqueue_head(&priv->delta_msr_wait);
 456
 457         usb_reset_configuration(serial->dev);
 458
 459         priv->cmd_ctrl = 0;
 460         priv->line_control = 0;
 461         priv->termios_initialized = 0;
 462         priv->rx_flags = 0;
 463         /* Default packet format setting is determined by packet size.
 464            Anything with a size larger then 9 must have a separate
 465            count field since the 3 bit count field is otherwise too
 466            small.  Otherwise we can use the slightly more compact
 467            format.  This is in accordance with the cypress_m8 serial
 468            converter app note. */
 469         if (port->interrupt_out_size > 9)
 470                 priv->pkt_fmt = packet_format_1;
 471         else
 472                 priv->pkt_fmt = packet_format_2;
 473
 474         if (interval > 0) {
 475                 priv->write_urb_interval = interval;
 476                 priv->read_urb_interval = interval;
 477                 dbg("%s - port %d read & write intervals forced to %d",
 478                     __func__, port->number, interval);
 479         } else {
 480                 priv->write_urb_interval = port->interrupt_out_urb->interval;
 481                 priv->read_urb_interval = port->interrupt_in_urb->interval;
 482                 dbg("%s - port %d intervals: read=%d write=%d",
 483                     __func__, port->number,
 484                     priv->read_urb_interval, priv->write_urb_interval);
 485         }
 486         usb_set_serial_port_data(port, priv);
 487
 488         return 0;
 489 }
 490
 491
 492 static int cypress_earthmate_startup(struct usb_serial *serial)
 493 {
 494         struct cypress_private *priv;
 495         struct usb_serial_port *port = serial->port[0];
 496
 497         if (generic_startup(serial)) {
 498                 dbg("%s - Failed setting up port %d", __func__,
 499                                 port->number);
 500                 return 1;
 501         }
 502
 503         priv = usb_get_serial_port_data(port);
 504         priv->chiptype = CT_EARTHMATE;
 505         /* All Earthmate devices use the separated-count packet
 506            format!  Idiotic. */
 507         priv->pkt_fmt = packet_format_1;
 508         if (serial->dev->descriptor.idProduct !=
 509                                 cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
 510                 /* The old original USB Earthmate seemed able to
 511                    handle GET_CONFIG requests; everything they've
 512                    produced since that time crashes if this command is
 513                    attempted :-( */
 514                 dbg("%s - Marking this device as unsafe for GET_CONFIG "
 515                     "commands", __func__);
 516                 priv->get_cfg_unsafe = !0;
 517         }
 518
 519         return 0;
 520 } /* cypress_earthmate_startup */
 521
 522
 523 static int cypress_hidcom_startup(struct usb_serial *serial)
 524 {
 525         struct cypress_private *priv;
 526
 527         if (generic_startup(serial)) {
 528                 dbg("%s - Failed setting up port %d", __func__,
 529                                 serial->port[0]->number);
 530                 return 1;
 531         }
 532
 533         priv = usb_get_serial_port_data(serial->port[0]);
 534         priv->chiptype = CT_CYPHIDCOM;
 535
 536         return 0;
 537 } /* cypress_hidcom_startup */
 538
 539
 540 static int cypress_ca42v2_startup(struct usb_serial *serial)
 541 {
 542         struct cypress_private *priv;
 543
 544         if (generic_startup(serial)) {
 545                 dbg("%s - Failed setting up port %d", __func__,
 546                                 serial->port[0]->number);
 547                 return 1;
 548         }
 549
 550         priv = usb_get_serial_port_data(serial->port[0]);
 551         priv->chiptype = CT_CA42V2;
 552
 553         return 0;
 554 } /* cypress_ca42v2_startup */
 555
 556
 557 static void cypress_release(struct usb_serial *serial)
 558 {
 559         struct cypress_private *priv;
 560
 561         /* all open ports are closed at this point */
 562         priv = usb_get_serial_port_data(serial->port[0]);
 563
 564         if (priv) {
 565                 kfifo_free(&priv->write_fifo);
 566                 kfree(priv);
 567         }
 568 }
 569
 570
 571 static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
 572 {
 573         struct cypress_private *priv = usb_get_serial_port_data(port);
 574         struct usb_serial *serial = port->serial;
 575         unsigned long flags;
 576         int result = 0;
 577
 578         if (!priv->comm_is_ok)
 579                 return -EIO;
 580
 581         /* clear halts before open */
 582         usb_clear_halt(serial->dev, 0x81);
 583         usb_clear_halt(serial->dev, 0x02);
 584
 585         spin_lock_irqsave(&priv->lock, flags);
 586         /* reset read/write statistics */
 587         priv->bytes_in = 0;
 588         priv->bytes_out = 0;
 589         priv->cmd_count = 0;
 590         priv->rx_flags = 0;
 591         spin_unlock_irqrestore(&priv->lock, flags);
 592
 593         /* Set termios */
 594         cypress_send(port);
 595
 596         if (tty)
 597                 cypress_set_termios(tty, port, &priv->tmp_termios);
 598
 599         /* setup the port and start reading from the device */
 600         if (!port->interrupt_in_urb) {
 601                 dev_err(&port->dev, "%s - interrupt_in_urb is empty!\n",
 602                         __func__);
 603                 return -1;
 604         }
 605
 606         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 607                 usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 608                 port->interrupt_in_urb->transfer_buffer,
 609                 port->interrupt_in_urb->transfer_buffer_length,
 610                 cypress_read_int_callback, port, priv->read_urb_interval);
 611         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 612
 613         if (result) {
 614                 dev_err(&port->dev,
 615                         "%s - failed submitting read urb, error %d\n",
 616                                                         __func__, result);
 617                 cypress_set_dead(port);
 618         }
 619         port->port.drain_delay = 256;
 620         return result;
 621 } /* cypress_open */
 622
 623 static void cypress_dtr_rts(struct usb_serial_port *port, int on)
 624 {
 625         struct cypress_private *priv = usb_get_serial_port_data(port);
 626         /* drop dtr and rts */
 627         spin_lock_irq(&priv->lock);
 628         if (on == 0)
 629                 priv->line_control = 0;
 630         else
 631                 priv->line_control = CONTROL_DTR | CONTROL_RTS;
 632         priv->cmd_ctrl = 1;
 633         spin_unlock_irq(&priv->lock);
 634         cypress_write(NULL, port, NULL, 0);
 635 }
 636
 637 static void cypress_close(struct usb_serial_port *port)
 638 {
 639         struct cypress_private *priv = usb_get_serial_port_data(port);
 640         unsigned long flags;
 641
 642         /* writing is potentially harmful, lock must be taken */
 643         mutex_lock(&port->serial->disc_mutex);
 644         if (port->serial->disconnected) {
 645                 mutex_unlock(&port->serial->disc_mutex);
 646                 return;
 647         }
 648         spin_lock_irqsave(&priv->lock, flags);
 649         kfifo_reset_out(&priv->write_fifo);
 650         spin_unlock_irqrestore(&priv->lock, flags);
 651
 652         dbg("%s - stopping urbs", __func__);
 653         usb_kill_urb(port->interrupt_in_urb);
 654         usb_kill_urb(port->interrupt_out_urb);
 655
 656         if (stats)
 657                 dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
 658                         priv->bytes_in, priv->bytes_out, priv->cmd_count);
 659         mutex_unlock(&port->serial->disc_mutex);
 660 } /* cypress_close */
 661
 662
 663 static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 664                                         const unsigned char *buf, int count)
 665 {
 666         struct cypress_private *priv = usb_get_serial_port_data(port);
 667
 668         dbg("%s - port %d, %d bytes", __func__, port->number, count);
 669
 670         /* line control commands, which need to be executed immediately,
 671            are not put into the buffer for obvious reasons.
 672          */
 673         if (priv->cmd_ctrl) {
 674                 count = 0;
 675                 goto finish;
 676         }
 677
 678         if (!count)
 679                 return count;
 680
 681         count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
 682
 683 finish:
 684         cypress_send(port);
 685
 686         return count;
 687 } /* cypress_write */
 688
 689
 690 static void cypress_send(struct usb_serial_port *port)
 691 {
 692         int count = 0, result, offset, actual_size;
 693         struct cypress_private *priv = usb_get_serial_port_data(port);
 694         unsigned long flags;
 695
 696         if (!priv->comm_is_ok)
 697                 return;
 698
 699         dbg("%s - interrupt out size is %d", __func__,
 700                                                 port->interrupt_out_size);
 701
 702         spin_lock_irqsave(&priv->lock, flags);
 703         if (priv->write_urb_in_use) {
 704                 dbg("%s - can't write, urb in use", __func__);
 705                 spin_unlock_irqrestore(&priv->lock, flags);
 706                 return;
 707         }
 708         spin_unlock_irqrestore(&priv->lock, flags);
 709
 710         /* clear buffer */
 711         memset(port->interrupt_out_urb->transfer_buffer, 0,
 712                                                 port->interrupt_out_size);
 713
 714         spin_lock_irqsave(&priv->lock, flags);
 715         switch (priv->pkt_fmt) {
 716         default:
 717         case packet_format_1:
 718                 /* this is for the CY7C64013... */
 719                 offset = 2;
 720                 port->interrupt_out_buffer[0] = priv->line_control;
 721                 break;
 722         case packet_format_2:
 723                 /* this is for the CY7C63743... */
 724                 offset = 1;
 725                 port->interrupt_out_buffer[0] = priv->line_control;
 726                 break;
 727         }
 728
 729         if (priv->line_control & CONTROL_RESET)
 730                 priv->line_control &= ~CONTROL_RESET;
 731
 732         if (priv->cmd_ctrl) {
 733                 priv->cmd_count++;
 734                 dbg("%s - line control command being issued", __func__);
 735                 spin_unlock_irqrestore(&priv->lock, flags);
 736                 goto send;
 737         } else
 738                 spin_unlock_irqrestore(&priv->lock, flags);
 739
 740         count = kfifo_out_locked(&priv->write_fifo,
 741                                         &port->interrupt_out_buffer[offset],
 742                                         port->interrupt_out_size - offset,
 743                                         &priv->lock);
 744         if (count == 0)
 745                 return;
 746
 747         switch (priv->pkt_fmt) {
 748         default:
 749         case packet_format_1:
 750                 port->interrupt_out_buffer[1] = count;
 751                 break;
 752         case packet_format_2:
 753                 port->interrupt_out_buffer[0] |= count;
 754         }
 755
 756         dbg("%s - count is %d", __func__, count);
 757
 758 send:
 759         spin_lock_irqsave(&priv->lock, flags);
 760         priv->write_urb_in_use = 1;
 761         spin_unlock_irqrestore(&priv->lock, flags);
 762
 763         if (priv->cmd_ctrl)
 764                 actual_size = 1;
 765         else
 766                 actual_size = count +
 767                               (priv->pkt_fmt == packet_format_1 ? 2 : 1);
 768
 769         usb_serial_debug_data(debug, &port->dev, __func__,
 770                 port->interrupt_out_size,
 771                 port->interrupt_out_urb->transfer_buffer);
 772
 773         usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
 774                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
 775                 port->interrupt_out_buffer, port->interrupt_out_size,
 776                 cypress_write_int_callback, port, priv->write_urb_interval);
 777         result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
 778         if (result) {
 779                 dev_err_console(port,
 780                                 "%s - failed submitting write urb, error %d\n",
 781                                                         __func__, result);
 782                 priv->write_urb_in_use = 0;
 783                 cypress_set_dead(port);
 784         }
 785
 786         spin_lock_irqsave(&priv->lock, flags);
 787         if (priv->cmd_ctrl)
 788                 priv->cmd_ctrl = 0;
 789
 790         /* do not count the line control and size bytes */
 791         priv->bytes_out += count;
 792         spin_unlock_irqrestore(&priv->lock, flags);
 793
 794         usb_serial_port_softint(port);
 795 } /* cypress_send */
 796
 797
 798 /* returns how much space is available in the soft buffer */
 799 static int cypress_write_room(struct tty_struct *tty)
 800 {
 801         struct usb_serial_port *port = tty->driver_data;
 802         struct cypress_private *priv = usb_get_serial_port_data(port);
 803         int room = 0;
 804         unsigned long flags;
 805
 806         spin_lock_irqsave(&priv->lock, flags);
 807         room = kfifo_avail(&priv->write_fifo);
 808         spin_unlock_irqrestore(&priv->lock, flags);
 809
 810         dbg("%s - returns %d", __func__, room);
 811         return room;
 812 }
 813
 814
 815 static int cypress_tiocmget(struct tty_struct *tty)
 816 {
 817         struct usb_serial_port *port = tty->driver_data;
 818         struct cypress_private *priv = usb_get_serial_port_data(port);
 819         __u8 status, control;
 820         unsigned int result = 0;
 821         unsigned long flags;
 822
 823         spin_lock_irqsave(&priv->lock, flags);
 824         control = priv->line_control;
 825         status = priv->current_status;
 826         spin_unlock_irqrestore(&priv->lock, flags);
 827
 828         result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
 829                 | ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
 830                 | ((status & UART_CTS)        ? TIOCM_CTS : 0)
 831                 | ((status & UART_DSR)        ? TIOCM_DSR : 0)
 832                 | ((status & UART_RI)         ? TIOCM_RI  : 0)
 833                 | ((status & UART_CD)         ? TIOCM_CD  : 0);
 834
 835         dbg("%s - result = %x", __func__, result);
 836
 837         return result;
 838 }
 839
 840
 841 static int cypress_tiocmset(struct tty_struct *tty,
 842                                unsigned int set, unsigned int clear)
 843 {
 844         struct usb_serial_port *port = tty->driver_data;
 845         struct cypress_private *priv = usb_get_serial_port_data(port);
 846         unsigned long flags;
 847
 848         spin_lock_irqsave(&priv->lock, flags);
 849         if (set & TIOCM_RTS)
 850                 priv->line_control |= CONTROL_RTS;
 851         if (set & TIOCM_DTR)
 852                 priv->line_control |= CONTROL_DTR;
 853         if (clear & TIOCM_RTS)
 854                 priv->line_control &= ~CONTROL_RTS;
 855         if (clear & TIOCM_DTR)
 856                 priv->line_control &= ~CONTROL_DTR;
 857         priv->cmd_ctrl = 1;
 858         spin_unlock_irqrestore(&priv->lock, flags);
 859
 860         return cypress_write(tty, port, NULL, 0);
 861 }
 862
 863
 864 static int cypress_ioctl(struct tty_struct *tty,
 865                                         unsigned int cmd, unsigned long arg)
 866 {
 867         struct usb_serial_port *port = tty->driver_data;
 868         struct cypress_private *priv = usb_get_serial_port_data(port);
 869
 870         dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
 871
 872         switch (cmd) {
 873         /* This code comes from drivers/char/serial.c and ftdi_sio.c */
 874         case TIOCMIWAIT:
 875                 while (priv != NULL) {
 876                         interruptible_sleep_on(&priv->delta_msr_wait);
 877                         /* see if a signal did it */
 878                         if (signal_pending(current))
 879                                 return -ERESTARTSYS;
 880                         else {
 881                                 char diff = priv->diff_status;
 882                                 if (diff == 0)
 883                                         return -EIO; /* no change => error */
 884
 885                                 /* consume all events */
 886                                 priv->diff_status = 0;
 887
 888                                 /* return 0 if caller wanted to know about
 889                                    these bits */
 890                                 if (((arg & TIOCM_RNG) && (diff & UART_RI)) ||
 891                                     ((arg & TIOCM_DSR) && (diff & UART_DSR)) ||
 892                                     ((arg & TIOCM_CD) && (diff & UART_CD)) ||
 893                                     ((arg & TIOCM_CTS) && (diff & UART_CTS)))
 894                                         return 0;
 895                                 /* otherwise caller can't care less about what
 896                                  * happened, and so we continue to wait for
 897                                  * more events.
 898                                  */
 899                         }
 900                 }
 901                 return 0;
 902         default:
 903                 break;
 904         }
 905         dbg("%s - arg not supported - it was 0x%04x - check include/asm/ioctls.h", __func__, cmd);
 906         return -ENOIOCTLCMD;
 907 } /* cypress_ioctl */
 908
 909
 910 static void cypress_set_termios(struct tty_struct *tty,
 911         struct usb_serial_port *port, struct ktermios *old_termios)
 912 {
 913         struct cypress_private *priv = usb_get_serial_port_data(port);
 914         int data_bits, stop_bits, parity_type, parity_enable;
 915         unsigned cflag, iflag;
 916         unsigned long flags;
 917         __u8 oldlines;
 918         int linechange = 0;
 919
 920         spin_lock_irqsave(&priv->lock, flags);
 921         /* We can't clean this one up as we don't know the device type
 922            early enough */
 923         if (!priv->termios_initialized) {
 924                 if (priv->chiptype == CT_EARTHMATE) {
 925                         *(tty->termios) = tty_std_termios;
 926                         tty->termios->c_cflag = B4800 | CS8 | CREAD | HUPCL |
 927                                 CLOCAL;
 928                         tty->termios->c_ispeed = 4800;
 929                         tty->termios->c_ospeed = 4800;
 930                 } else if (priv->chiptype == CT_CYPHIDCOM) {
 931                         *(tty->termios) = tty_std_termios;
 932                         tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
 933                                 CLOCAL;
 934                         tty->termios->c_ispeed = 9600;
 935                         tty->termios->c_ospeed = 9600;
 936                 } else if (priv->chiptype == CT_CA42V2) {
 937                         *(tty->termios) = tty_std_termios;
 938                         tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
 939                                 CLOCAL;
 940                         tty->termios->c_ispeed = 9600;
 941                         tty->termios->c_ospeed = 9600;
 942                 }
 943                 priv->termios_initialized = 1;
 944         }
 945         spin_unlock_irqrestore(&priv->lock, flags);
 946
 947         /* Unsupported features need clearing */
 948         tty->termios->c_cflag &= ~(CMSPAR|CRTSCTS);
 949
 950         cflag = tty->termios->c_cflag;
 951         iflag = tty->termios->c_iflag;
 952
 953         /* check if there are new settings */
 954         if (old_termios) {
 955                 spin_lock_irqsave(&priv->lock, flags);
 956                 priv->tmp_termios = *(tty->termios);
 957                 spin_unlock_irqrestore(&priv->lock, flags);
 958         }
 959
 960         /* set number of data bits, parity, stop bits */
 961         /* when parity is disabled the parity type bit is ignored */
 962
 963         /* 1 means 2 stop bits, 0 means 1 stop bit */
 964         stop_bits = cflag & CSTOPB ? 1 : 0;
 965
 966         if (cflag & PARENB) {
 967                 parity_enable = 1;
 968                 /* 1 means odd parity, 0 means even parity */
 969                 parity_type = cflag & PARODD ? 1 : 0;
 970         } else
 971                 parity_enable = parity_type = 0;
 972
 973         switch (cflag & CSIZE) {
 974         case CS5:
 975                 data_bits = 0;
 976                 break;
 977         case CS6:
 978                 data_bits = 1;
 979                 break;
 980         case CS7:
 981                 data_bits = 2;
 982                 break;
 983         case CS8:
 984                 data_bits = 3;
 985                 break;
 986         default:
 987                 dev_err(&port->dev, "%s - CSIZE was set, but not CS5-CS8\n",
 988                         __func__);
 989                 data_bits = 3;
 990         }
 991         spin_lock_irqsave(&priv->lock, flags);
 992         oldlines = priv->line_control;
 993         if ((cflag & CBAUD) == B0) {
 994                 /* drop dtr and rts */
 995                 dbg("%s - dropping the lines, baud rate 0bps", __func__);
 996                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 997         } else
 998                 priv->line_control = (CONTROL_DTR | CONTROL_RTS);
 999         spin_unlock_irqrestore(&priv->lock, flags);
1000
1001         dbg("%s - sending %d stop_bits, %d parity_enable, %d parity_type, "
1002                         "%d data_bits (+5)", __func__, stop_bits,
1003                         parity_enable, parity_type, data_bits);
1004
1005         cypress_serial_control(tty, port, tty_get_baud_rate(tty),
1006                         data_bits, stop_bits,
1007                         parity_enable, parity_type,
1008                         0, CYPRESS_SET_CONFIG);
1009
1010         /* we perform a CYPRESS_GET_CONFIG so that the current settings are
1011          * filled into the private structure this should confirm that all is
1012          * working if it returns what we just set */
1013         cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
1014
1015         /* Here we can define custom tty settings for devices; the main tty
1016          * termios flag base comes from empeg.c */
1017
1018         spin_lock_irqsave(&priv->lock, flags);
1019         if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
1020                 dbg("Using custom termios settings for a baud rate of "
1021                                 "4800bps.");
1022                 /* define custom termios settings for NMEA protocol */
1023
1024                 tty->termios->c_iflag /* input modes - */
1025                         &= ~(IGNBRK  /* disable ignore break */
1026                         | BRKINT     /* disable break causes interrupt */
1027                         | PARMRK     /* disable mark parity errors */
1028                         | ISTRIP     /* disable clear high bit of input char */
1029                         | INLCR      /* disable translate NL to CR */
1030                         | IGNCR      /* disable ignore CR */
1031                         | ICRNL      /* disable translate CR to NL */
1032                         | IXON);     /* disable enable XON/XOFF flow control */
1033
1034                 tty->termios->c_oflag /* output modes */
1035                         &= ~OPOST;    /* disable postprocess output char */
1036
1037                 tty->termios->c_lflag /* line discipline modes */
1038                         &= ~(ECHO     /* disable echo input characters */
1039                         | ECHONL      /* disable echo new line */
1040                         | ICANON      /* disable erase, kill, werase, and rprnt
1041                                          special characters */
1042                         | ISIG        /* disable interrupt, quit, and suspend
1043                                          special characters */
1044                         | IEXTEN);    /* disable non-POSIX special characters */
1045         } /* CT_CYPHIDCOM: Application should handle this for device */
1046
1047         linechange = (priv->line_control != oldlines);
1048         spin_unlock_irqrestore(&priv->lock, flags);
1049
1050         /* if necessary, set lines */
1051         if (linechange) {
1052                 priv->cmd_ctrl = 1;
1053                 cypress_write(tty, port, NULL, 0);
1054         }
1055 } /* cypress_set_termios */
1056
1057
1058 /* returns amount of data still left in soft buffer */
1059 static int cypress_chars_in_buffer(struct tty_struct *tty)
1060 {
1061         struct usb_serial_port *port = tty->driver_data;
1062         struct cypress_private *priv = usb_get_serial_port_data(port);
1063         int chars = 0;
1064         unsigned long flags;
1065
1066         spin_lock_irqsave(&priv->lock, flags);
1067         chars = kfifo_len(&priv->write_fifo);
1068         spin_unlock_irqrestore(&priv->lock, flags);
1069
1070         dbg("%s - returns %d", __func__, chars);
1071         return chars;
1072 }
1073
1074
1075 static void cypress_throttle(struct tty_struct *tty)
1076 {
1077         struct usb_serial_port *port = tty->driver_data;
1078         struct cypress_private *priv = usb_get_serial_port_data(port);
1079
1080         spin_lock_irq(&priv->lock);
1081         priv->rx_flags = THROTTLED;
1082         spin_unlock_irq(&priv->lock);
1083 }
1084
1085
1086 static void cypress_unthrottle(struct tty_struct *tty)
1087 {
1088         struct usb_serial_port *port = tty->driver_data;
1089         struct cypress_private *priv = usb_get_serial_port_data(port);
1090         int actually_throttled, result;
1091
1092         spin_lock_irq(&priv->lock);
1093         actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1094         priv->rx_flags = 0;
1095         spin_unlock_irq(&priv->lock);
1096
1097         if (!priv->comm_is_ok)
1098                 return;
1099
1100         if (actually_throttled) {
1101                 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1102                 if (result) {
1103                         dev_err(&port->dev, "%s - failed submitting read urb, "
1104                                         "error %d\n", __func__, result);
1105                         cypress_set_dead(port);
1106                 }
1107         }
1108 }
1109
1110
1111 static void cypress_read_int_callback(struct urb *urb)
1112 {
1113         struct usb_serial_port *port = urb->context;
1114         struct cypress_private *priv = usb_get_serial_port_data(port);
1115         struct tty_struct *tty;
1116         unsigned char *data = urb->transfer_buffer;
1117         unsigned long flags;
1118         char tty_flag = TTY_NORMAL;
1119         int havedata = 0;
1120         int bytes = 0;
1121         int result;
1122         int i = 0;
1123         int status = urb->status;
1124
1125         switch (status) {
1126         case 0: /* success */
1127                 break;
1128         case -ECONNRESET:
1129         case -ENOENT:
1130         case -ESHUTDOWN:
1131                 /* precursor to disconnect so just go away */
1132                 return;
1133         case -EPIPE:
1134                 /* Can't call usb_clear_halt while in_interrupt */
1135                 /* FALLS THROUGH */
1136         default:
1137                 /* something ugly is going on... */
1138                 dev_err(&urb->dev->dev,
1139                         "%s - unexpected nonzero read status received: %d\n",
1140                                                         __func__, status);
1141                 cypress_set_dead(port);
1142                 return;
1143         }
1144
1145         spin_lock_irqsave(&priv->lock, flags);
1146         if (priv->rx_flags & THROTTLED) {
1147                 dbg("%s - now throttling", __func__);
1148                 priv->rx_flags |= ACTUALLY_THROTTLED;
1149                 spin_unlock_irqrestore(&priv->lock, flags);
1150                 return;
1151         }
1152         spin_unlock_irqrestore(&priv->lock, flags);
1153
1154         tty = tty_port_tty_get(&port->port);
1155         if (!tty) {
1156                 dbg("%s - bad tty pointer - exiting", __func__);
1157                 return;
1158         }
1159
1160         spin_lock_irqsave(&priv->lock, flags);
1161         result = urb->actual_length;
1162         switch (priv->pkt_fmt) {
1163         default:
1164         case packet_format_1:
1165                 /* This is for the CY7C64013... */
1166                 priv->current_status = data[0] & 0xF8;
1167                 bytes = data[1] + 2;
1168                 i = 2;
1169                 if (bytes > 2)
1170                         havedata = 1;
1171                 break;
1172         case packet_format_2:
1173                 /* This is for the CY7C63743... */
1174                 priv->current_status = data[0] & 0xF8;
1175                 bytes = (data[0] & 0x07) + 1;
1176                 i = 1;
1177                 if (bytes > 1)
1178                         havedata = 1;
1179                 break;
1180         }
1181         spin_unlock_irqrestore(&priv->lock, flags);
1182         if (result < bytes) {
1183                 dbg("%s - wrong packet size - received %d bytes but packet "
1184                     "said %d bytes", __func__, result, bytes);
1185                 goto continue_read;
1186         }
1187
1188         usb_serial_debug_data(debug, &port->dev, __func__,
1189                                                 urb->actual_length, data);
1190
1191         spin_lock_irqsave(&priv->lock, flags);
1192         /* check to see if status has changed */
1193         if (priv->current_status != priv->prev_status) {
1194                 priv->diff_status |= priv->current_status ^
1195                         priv->prev_status;
1196                 wake_up_interruptible(&priv->delta_msr_wait);
1197                 priv->prev_status = priv->current_status;
1198         }
1199         spin_unlock_irqrestore(&priv->lock, flags);
1200
1201         /* hangup, as defined in acm.c... this might be a bad place for it
1202          * though */
1203         if (tty && !(tty->termios->c_cflag & CLOCAL) &&
1204                         !(priv->current_status & UART_CD)) {
1205                 dbg("%s - calling hangup", __func__);
1206                 tty_hangup(tty);
1207                 goto continue_read;
1208         }
1209
1210         /* There is one error bit... I'm assuming it is a parity error
1211          * indicator as the generic firmware will set this bit to 1 if a
1212          * parity error occurs.
1213          * I can not find reference to any other error events. */
1214         spin_lock_irqsave(&priv->lock, flags);
1215         if (priv->current_status & CYP_ERROR) {
1216                 spin_unlock_irqrestore(&priv->lock, flags);
1217                 tty_flag = TTY_PARITY;
1218                 dbg("%s - Parity Error detected", __func__);
1219         } else
1220                 spin_unlock_irqrestore(&priv->lock, flags);
1221
1222         /* process read if there is data other than line status */
1223         if (tty && bytes > i) {
1224                 tty_insert_flip_string_fixed_flag(tty, data + i,
1225                                 tty_flag, bytes - i);
1226                 tty_flip_buffer_push(tty);
1227         }
1228
1229         spin_lock_irqsave(&priv->lock, flags);
1230         /* control and status byte(s) are also counted */
1231         priv->bytes_in += bytes;
1232         spin_unlock_irqrestore(&priv->lock, flags);
1233
1234 continue_read:
1235         tty_kref_put(tty);
1236
1237         /* Continue trying to always read */
1238
1239         if (priv->comm_is_ok) {
1240                 usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1241                                 usb_rcvintpipe(port->serial->dev,
1242                                         port->interrupt_in_endpointAddress),
1243                                 port->interrupt_in_urb->transfer_buffer,
1244                                 port->interrupt_in_urb->transfer_buffer_length,
1245                                 cypress_read_int_callback, port,
1246                                 priv->read_urb_interval);
1247                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1248                 if (result && result != -EPERM) {
1249                         dev_err(&urb->dev->dev, "%s - failed resubmitting "
1250                                         "read urb, error %d\n", __func__,
1251                                         result);
1252                         cypress_set_dead(port);
1253                 }
1254         }
1255 } /* cypress_read_int_callback */
1256
1257
1258 static void cypress_write_int_callback(struct urb *urb)
1259 {
1260         struct usb_serial_port *port = urb->context;
1261         struct cypress_private *priv = usb_get_serial_port_data(port);
1262         int result;
1263         int status = urb->status;
1264
1265         switch (status) {
1266         case 0:
1267                 /* success */
1268                 break;
1269         case -ECONNRESET:
1270         case -ENOENT:
1271         case -ESHUTDOWN:
1272                 /* this urb is terminated, clean up */
1273                 dbg("%s - urb shutting down with status: %d",
1274                                                 __func__, status);
1275                 priv->write_urb_in_use = 0;
1276                 return;
1277         case -EPIPE: /* no break needed; clear halt and resubmit */
1278                 if (!priv->comm_is_ok)
1279                         break;
1280                 usb_clear_halt(port->serial->dev, 0x02);
1281                 /* error in the urb, so we have to resubmit it */
1282                 dbg("%s - nonzero write bulk status received: %d",
1283                         __func__, status);
1284                 port->interrupt_out_urb->transfer_buffer_length = 1;
1285                 result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
1286                 if (!result)
1287                         return;
1288                 dev_err(&urb->dev->dev,
1289                         "%s - failed resubmitting write urb, error %d\n",
1290                                                         __func__, result);
1291                 cypress_set_dead(port);
1292                 break;
1293         default:
1294                 dev_err(&urb->dev->dev,
1295                          "%s - unexpected nonzero write status received: %d\n",
1296                                                         __func__, status);
1297                 cypress_set_dead(port);
1298                 break;
1299         }
1300         priv->write_urb_in_use = 0;
1301
1302         /* send any buffered data */
1303         cypress_send(port);
1304 }
1305
1306 module_usb_serial_driver(serial_drivers, id_table_combined);
1307
1308 MODULE_AUTHOR(DRIVER_AUTHOR);
1309 MODULE_DESCRIPTION(DRIVER_DESC);
1310 MODULE_VERSION(DRIVER_VERSION);
1311 MODULE_LICENSE("GPL");
1312
1313 module_param(debug, bool, S_IRUGO | S_IWUSR);
1314 MODULE_PARM_DESC(debug, "Debug enabled or not");
1315 module_param(stats, bool, S_IRUGO | S_IWUSR);
1316 MODULE_PARM_DESC(stats, "Enable statistics or not");
1317 module_param(interval, int, S_IRUGO | S_IWUSR);
1318 MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1319 module_param(unstable_bauds, bool, S_IRUGO | S_IWUSR);
1320 MODULE_PARM_DESC(unstable_bauds, "Allow unstable baud rates");