drivers/usb/serial/cypress_m8.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * USB Cypress M8 driver
   4  *
   5  *      Copyright (C) 2004
   6  *          Lonnie Mendez ([email protected])
   7  *      Copyright (C) 2003,2004
   8  *          Neil Whelchel ([email protected])
   9  *
  10  * See Documentation/usb/usb-serial.txt for more information on using this
  11  * driver
  12  *
  13  * See http://geocities.com/i0xox0i for information on this driver and the
  14  * earthmate usb device.
  15  */
  16
  17 /* Thanks to Neil Whelchel for writing the first cypress m8 implementation
  18    for linux. */
  19 /* Thanks to cypress for providing references for the hid reports. */
  20 /* Thanks to Jiang Zhang for providing links and for general help. */
  21 /* Code originates and was built up from ftdi_sio, belkin, pl2303 and others.*/
  22
  23
  24 #include <linux/kernel.h>
  25 #include <linux/errno.h>
  26 #include <linux/slab.h>
  27 #include <linux/tty.h>
  28 #include <linux/tty_driver.h>
  29 #include <linux/tty_flip.h>
  30 #include <linux/module.h>
  31 #include <linux/moduleparam.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/usb.h>
  34 #include <linux/usb/serial.h>
  35 #include <linux/serial.h>
  36 #include <linux/kfifo.h>
  37 #include <linux/delay.h>
  38 #include <linux/uaccess.h>
  39 #include <asm/unaligned.h>
  40
  41 #include "cypress_m8.h"
  42
  43
  44 static bool stats;
  45 static int interval;
  46 static bool unstable_bauds;
  47
  48 #define DRIVER_AUTHOR "Lonnie Mendez <[email protected]>, Neil Whelchel <[email protected]>"
  49 #define DRIVER_DESC "Cypress USB to Serial Driver"
  50
  51 /* write buffer size defines */
  52 #define CYPRESS_BUF_SIZE        1024
  53
  54 static const struct usb_device_id id_table_earthmate[] = {
  55         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  56         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  57         { }                                             /* Terminating entry */
  58 };
  59
  60 static const struct usb_device_id id_table_cyphidcomrs232[] = {
  61         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  62         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  63         { USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
  64         { }                                             /* Terminating entry */
  65 };
  66
  67 static const struct usb_device_id id_table_nokiaca42v2[] = {
  68         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  69         { }                                             /* Terminating entry */
  70 };
  71
  72 static const struct usb_device_id id_table_combined[] = {
  73         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  74         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  75         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  76         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  77         { USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
  78         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  79         { }                                             /* Terminating entry */
  80 };
  81
  82 MODULE_DEVICE_TABLE(usb, id_table_combined);
  83
  84 enum packet_format {
  85         packet_format_1,  /* b0:status, b1:payload count */
  86         packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
  87 };
  88
  89 struct cypress_private {
  90         spinlock_t lock;                   /* private lock */
  91         int chiptype;                      /* identifier of device, for quirks/etc */
  92         int bytes_in;                      /* used for statistics */
  93         int bytes_out;                     /* used for statistics */
  94         int cmd_count;                     /* used for statistics */
  95         int cmd_ctrl;                      /* always set this to 1 before issuing a command */
  96         struct kfifo write_fifo;           /* write fifo */
  97         int write_urb_in_use;              /* write urb in use indicator */
  98         int write_urb_interval;            /* interval to use for write urb */
  99         int read_urb_interval;             /* interval to use for read urb */
 100         int comm_is_ok;                    /* true if communication is (still) ok */
 101         int termios_initialized;
 102         __u8 line_control;                 /* holds dtr / rts value */
 103         __u8 current_status;               /* received from last read - info on dsr,cts,cd,ri,etc */
 104         __u8 current_config;               /* stores the current configuration byte */
 105         __u8 rx_flags;                     /* throttling - used from whiteheat/ftdi_sio */
 106         enum packet_format pkt_fmt;        /* format to use for packet send / receive */
 107         int get_cfg_unsafe;                /* If true, the CYPRESS_GET_CONFIG is unsafe */
 108         int baud_rate;                     /* stores current baud rate in
 109                                               integer form */
 110         int isthrottled;                   /* if throttled, discard reads */
 111         char prev_status;                  /* used for TIOCMIWAIT */
 112         /* we pass a pointer to this as the argument sent to
 113            cypress_set_termios old_termios */
 114         struct ktermios tmp_termios;       /* stores the old termios settings */
 115 };
 116
 117 /* function prototypes for the Cypress USB to serial device */
 118 static int  cypress_earthmate_port_probe(struct usb_serial_port *port);
 119 static int  cypress_hidcom_port_probe(struct usb_serial_port *port);
 120 static int  cypress_ca42v2_port_probe(struct usb_serial_port *port);
 121 static int  cypress_port_remove(struct usb_serial_port *port);
 122 static int  cypress_open(struct tty_struct *tty, struct usb_serial_port *port);
 123 static void cypress_close(struct usb_serial_port *port);
 124 static void cypress_dtr_rts(struct usb_serial_port *port, int on);
 125 static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 126                         const unsigned char *buf, int count);
 127 static void cypress_send(struct usb_serial_port *port);
 128 static int  cypress_write_room(struct tty_struct *tty);
 129 static void cypress_set_termios(struct tty_struct *tty,
 130                         struct usb_serial_port *port, struct ktermios *old);
 131 static int  cypress_tiocmget(struct tty_struct *tty);
 132 static int  cypress_tiocmset(struct tty_struct *tty,
 133                         unsigned int set, unsigned int clear);
 134 static int  cypress_chars_in_buffer(struct tty_struct *tty);
 135 static void cypress_throttle(struct tty_struct *tty);
 136 static void cypress_unthrottle(struct tty_struct *tty);
 137 static void cypress_set_dead(struct usb_serial_port *port);
 138 static void cypress_read_int_callback(struct urb *urb);
 139 static void cypress_write_int_callback(struct urb *urb);
 140
 141 static struct usb_serial_driver cypress_earthmate_device = {
 142         .driver = {
 143                 .owner =                THIS_MODULE,
 144                 .name =                 "earthmate",
 145         },
 146         .description =                  "DeLorme Earthmate USB",
 147         .id_table =                     id_table_earthmate,
 148         .num_ports =                    1,
 149         .port_probe =                   cypress_earthmate_port_probe,
 150         .port_remove =                  cypress_port_remove,
 151         .open =                         cypress_open,
 152         .close =                        cypress_close,
 153         .dtr_rts =                      cypress_dtr_rts,
 154         .write =                        cypress_write,
 155         .write_room =                   cypress_write_room,
 156         .set_termios =                  cypress_set_termios,
 157         .tiocmget =                     cypress_tiocmget,
 158         .tiocmset =                     cypress_tiocmset,
 159         .tiocmiwait =                   usb_serial_generic_tiocmiwait,
 160         .chars_in_buffer =              cypress_chars_in_buffer,
 161         .throttle =                     cypress_throttle,
 162         .unthrottle =                   cypress_unthrottle,
 163         .read_int_callback =            cypress_read_int_callback,
 164         .write_int_callback =           cypress_write_int_callback,
 165 };
 166
 167 static struct usb_serial_driver cypress_hidcom_device = {
 168         .driver = {
 169                 .owner =                THIS_MODULE,
 170                 .name =                 "cyphidcom",
 171         },
 172         .description =                  "HID->COM RS232 Adapter",
 173         .id_table =                     id_table_cyphidcomrs232,
 174         .num_ports =                    1,
 175         .port_probe =                   cypress_hidcom_port_probe,
 176         .port_remove =                  cypress_port_remove,
 177         .open =                         cypress_open,
 178         .close =                        cypress_close,
 179         .dtr_rts =                      cypress_dtr_rts,
 180         .write =                        cypress_write,
 181         .write_room =                   cypress_write_room,
 182         .set_termios =                  cypress_set_termios,
 183         .tiocmget =                     cypress_tiocmget,
 184         .tiocmset =                     cypress_tiocmset,
 185         .tiocmiwait =                   usb_serial_generic_tiocmiwait,
 186         .chars_in_buffer =              cypress_chars_in_buffer,
 187         .throttle =                     cypress_throttle,
 188         .unthrottle =                   cypress_unthrottle,
 189         .read_int_callback =            cypress_read_int_callback,
 190         .write_int_callback =           cypress_write_int_callback,
 191 };
 192
 193 static struct usb_serial_driver cypress_ca42v2_device = {
 194         .driver = {
 195                 .owner =                THIS_MODULE,
 196                 .name =                 "nokiaca42v2",
 197         },
 198         .description =                  "Nokia CA-42 V2 Adapter",
 199         .id_table =                     id_table_nokiaca42v2,
 200         .num_ports =                    1,
 201         .port_probe =                   cypress_ca42v2_port_probe,
 202         .port_remove =                  cypress_port_remove,
 203         .open =                         cypress_open,
 204         .close =                        cypress_close,
 205         .dtr_rts =                      cypress_dtr_rts,
 206         .write =                        cypress_write,
 207         .write_room =                   cypress_write_room,
 208         .set_termios =                  cypress_set_termios,
 209         .tiocmget =                     cypress_tiocmget,
 210         .tiocmset =                     cypress_tiocmset,
 211         .tiocmiwait =                   usb_serial_generic_tiocmiwait,
 212         .chars_in_buffer =              cypress_chars_in_buffer,
 213         .throttle =                     cypress_throttle,
 214         .unthrottle =                   cypress_unthrottle,
 215         .read_int_callback =            cypress_read_int_callback,
 216         .write_int_callback =           cypress_write_int_callback,
 217 };
 218
 219 static struct usb_serial_driver * const serial_drivers[] = {
 220         &cypress_earthmate_device, &cypress_hidcom_device,
 221         &cypress_ca42v2_device, NULL
 222 };
 223
 224 /*****************************************************************************
 225  * Cypress serial helper functions
 226  *****************************************************************************/
 227
 228 /* FRWD Dongle hidcom needs to skip reset and speed checks */
 229 static inline bool is_frwd(struct usb_device *dev)
 230 {
 231         return ((le16_to_cpu(dev->descriptor.idVendor) == VENDOR_ID_FRWD) &&
 232                 (le16_to_cpu(dev->descriptor.idProduct) == PRODUCT_ID_CYPHIDCOM_FRWD));
 233 }
 234
 235 static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
 236 {
 237         struct cypress_private *priv;
 238         priv = usb_get_serial_port_data(port);
 239
 240         if (unstable_bauds)
 241                 return new_rate;
 242
 243         /* FRWD Dongle uses 115200 bps */
 244         if (is_frwd(port->serial->dev))
 245                 return new_rate;
 246
 247         /*
 248          * The general purpose firmware for the Cypress M8 allows for
 249          * a maximum speed of 57600bps (I have no idea whether DeLorme
 250          * chose to use the general purpose firmware or not), if you
 251          * need to modify this speed setting for your own project
 252          * please add your own chiptype and modify the code likewise.
 253          * The Cypress HID->COM device will work successfully up to
 254          * 115200bps (but the actual throughput is around 3kBps).
 255          */
 256         if (port->serial->dev->speed == USB_SPEED_LOW) {
 257                 /*
 258                  * Mike Isely <[email protected]> 2-Feb-2008: The
 259                  * Cypress app note that describes this mechanism
 260                  * states the the low-speed part can't handle more
 261                  * than 800 bytes/sec, in which case 4800 baud is the
 262                  * safest speed for a part like that.
 263                  */
 264                 if (new_rate > 4800) {
 265                         dev_dbg(&port->dev,
 266                                 "%s - failed setting baud rate, device incapable speed %d\n",
 267                                 __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                         dev_dbg(&port->dev,
 278                                 "%s - failed setting baud rate, unsupported speed of %d on Earthmate GPS\n",
 279                                 __func__, new_rate);
 280                         return -1;
 281                 }
 282                 break;
 283         default:
 284                 break;
 285         }
 286         return new_rate;
 287 }
 288
 289
 290 /* This function can either set or retrieve the current serial line settings */
 291 static int cypress_serial_control(struct tty_struct *tty,
 292         struct usb_serial_port *port, speed_t baud_rate, int data_bits,
 293         int stop_bits, int parity_enable, int parity_type, int reset,
 294         int cypress_request_type)
 295 {
 296         int new_baudrate = 0, retval = 0, tries = 0;
 297         struct cypress_private *priv;
 298         struct device *dev = &port->dev;
 299         u8 *feature_buffer;
 300         const unsigned int feature_len = 5;
 301         unsigned long flags;
 302
 303         priv = usb_get_serial_port_data(port);
 304
 305         if (!priv->comm_is_ok)
 306                 return -ENODEV;
 307
 308         feature_buffer = kcalloc(feature_len, sizeof(u8), GFP_KERNEL);
 309         if (!feature_buffer)
 310                 return -ENOMEM;
 311
 312         switch (cypress_request_type) {
 313         case CYPRESS_SET_CONFIG:
 314                 /* 0 means 'Hang up' so doesn't change the true bit rate */
 315                 new_baudrate = priv->baud_rate;
 316                 if (baud_rate && baud_rate != priv->baud_rate) {
 317                         dev_dbg(dev, "%s - baud rate is changing\n", __func__);
 318                         retval = analyze_baud_rate(port, baud_rate);
 319                         if (retval >= 0) {
 320                                 new_baudrate = retval;
 321                                 dev_dbg(dev, "%s - New baud rate set to %d\n",
 322                                         __func__, new_baudrate);
 323                         }
 324                 }
 325                 dev_dbg(dev, "%s - baud rate is being sent as %d\n", __func__,
 326                         new_baudrate);
 327
 328                 /* fill the feature_buffer with new configuration */
 329                 put_unaligned_le32(new_baudrate, feature_buffer);
 330                 feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
 331                 /* 1 bit gap */
 332                 feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
 333                 feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
 334                 feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
 335                 /* 1 bit gap */
 336                 feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
 337
 338                 dev_dbg(dev, "%s - device is being sent this feature report:\n", __func__);
 339                 dev_dbg(dev, "%s - %02X - %02X - %02X - %02X - %02X\n", __func__,
 340                         feature_buffer[0], feature_buffer[1],
 341                         feature_buffer[2], feature_buffer[3],
 342                         feature_buffer[4]);
 343
 344                 do {
 345                         retval = usb_control_msg(port->serial->dev,
 346                                         usb_sndctrlpipe(port->serial->dev, 0),
 347                                         HID_REQ_SET_REPORT,
 348                                         USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 349                                         0x0300, 0, feature_buffer,
 350                                         feature_len, 500);
 351
 352                         if (tries++ >= 3)
 353                                 break;
 354
 355                 } while (retval != feature_len &&
 356                          retval != -ENODEV);
 357
 358                 if (retval != feature_len) {
 359                         dev_err(dev, "%s - failed sending serial line settings - %d\n",
 360                                 __func__, retval);
 361                         cypress_set_dead(port);
 362                 } else {
 363                         spin_lock_irqsave(&priv->lock, flags);
 364                         priv->baud_rate = new_baudrate;
 365                         priv->current_config = feature_buffer[4];
 366                         spin_unlock_irqrestore(&priv->lock, flags);
 367                         /* If we asked for a speed change encode it */
 368                         if (baud_rate)
 369                                 tty_encode_baud_rate(tty,
 370                                         new_baudrate, new_baudrate);
 371                 }
 372         break;
 373         case CYPRESS_GET_CONFIG:
 374                 if (priv->get_cfg_unsafe) {
 375                         /* Not implemented for this device,
 376                            and if we try to do it we're likely
 377                            to crash the hardware. */
 378                         retval = -ENOTTY;
 379                         goto out;
 380                 }
 381                 dev_dbg(dev, "%s - retreiving serial line settings\n", __func__);
 382                 do {
 383                         retval = usb_control_msg(port->serial->dev,
 384                                         usb_rcvctrlpipe(port->serial->dev, 0),
 385                                         HID_REQ_GET_REPORT,
 386                                         USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 387                                         0x0300, 0, feature_buffer,
 388                                         feature_len, 500);
 389
 390                         if (tries++ >= 3)
 391                                 break;
 392                 } while (retval != feature_len
 393                                                 && retval != -ENODEV);
 394
 395                 if (retval != feature_len) {
 396                         dev_err(dev, "%s - failed to retrieve serial line settings - %d\n",
 397                                 __func__, retval);
 398                         cypress_set_dead(port);
 399                         goto out;
 400                 } else {
 401                         spin_lock_irqsave(&priv->lock, flags);
 402                         /* store the config in one byte, and later
 403                            use bit masks to check values */
 404                         priv->current_config = feature_buffer[4];
 405                         priv->baud_rate = get_unaligned_le32(feature_buffer);
 406                         spin_unlock_irqrestore(&priv->lock, flags);
 407                 }
 408         }
 409         spin_lock_irqsave(&priv->lock, flags);
 410         ++priv->cmd_count;
 411         spin_unlock_irqrestore(&priv->lock, flags);
 412 out:
 413         kfree(feature_buffer);
 414         return retval;
 415 } /* cypress_serial_control */
 416
 417
 418 static void cypress_set_dead(struct usb_serial_port *port)
 419 {
 420         struct cypress_private *priv = usb_get_serial_port_data(port);
 421         unsigned long flags;
 422
 423         spin_lock_irqsave(&priv->lock, flags);
 424         if (!priv->comm_is_ok) {
 425                 spin_unlock_irqrestore(&priv->lock, flags);
 426                 return;
 427         }
 428         priv->comm_is_ok = 0;
 429         spin_unlock_irqrestore(&priv->lock, flags);
 430
 431         dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
 432                 "interval might be too short\n", port->port_number);
 433 }
 434
 435
 436 /*****************************************************************************
 437  * Cypress serial driver functions
 438  *****************************************************************************/
 439
 440
 441 static int cypress_generic_port_probe(struct usb_serial_port *port)
 442 {
 443         struct usb_serial *serial = port->serial;
 444         struct cypress_private *priv;
 445
 446         if (!port->interrupt_out_urb || !port->interrupt_in_urb) {
 447                 dev_err(&port->dev, "required endpoint is missing\n");
 448                 return -ENODEV;
 449         }
 450
 451         priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
 452         if (!priv)
 453                 return -ENOMEM;
 454
 455         priv->comm_is_ok = !0;
 456         spin_lock_init(&priv->lock);
 457         if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
 458                 kfree(priv);
 459                 return -ENOMEM;
 460         }
 461
 462         /* Skip reset for FRWD device. It is a workaound:
 463            device hangs if it receives SET_CONFIGURE in Configured
 464            state. */
 465         if (!is_frwd(serial->dev))
 466                 usb_reset_configuration(serial->dev);
 467
 468         priv->cmd_ctrl = 0;
 469         priv->line_control = 0;
 470         priv->termios_initialized = 0;
 471         priv->rx_flags = 0;
 472         /* Default packet format setting is determined by packet size.
 473            Anything with a size larger then 9 must have a separate
 474            count field since the 3 bit count field is otherwise too
 475            small.  Otherwise we can use the slightly more compact
 476            format.  This is in accordance with the cypress_m8 serial
 477            converter app note. */
 478         if (port->interrupt_out_size > 9)
 479                 priv->pkt_fmt = packet_format_1;
 480         else
 481                 priv->pkt_fmt = packet_format_2;
 482
 483         if (interval > 0) {
 484                 priv->write_urb_interval = interval;
 485                 priv->read_urb_interval = interval;
 486                 dev_dbg(&port->dev, "%s - read & write intervals forced to %d\n",
 487                         __func__, interval);
 488         } else {
 489                 priv->write_urb_interval = port->interrupt_out_urb->interval;
 490                 priv->read_urb_interval = port->interrupt_in_urb->interval;
 491                 dev_dbg(&port->dev, "%s - intervals: read=%d write=%d\n",
 492                         __func__, priv->read_urb_interval,
 493                         priv->write_urb_interval);
 494         }
 495         usb_set_serial_port_data(port, priv);
 496
 497         port->port.drain_delay = 256;
 498
 499         return 0;
 500 }
 501
 502
 503 static int cypress_earthmate_port_probe(struct usb_serial_port *port)
 504 {
 505         struct usb_serial *serial = port->serial;
 506         struct cypress_private *priv;
 507         int ret;
 508
 509         ret = cypress_generic_port_probe(port);
 510         if (ret) {
 511                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 512                 return ret;
 513         }
 514
 515         priv = usb_get_serial_port_data(port);
 516         priv->chiptype = CT_EARTHMATE;
 517         /* All Earthmate devices use the separated-count packet
 518            format!  Idiotic. */
 519         priv->pkt_fmt = packet_format_1;
 520         if (serial->dev->descriptor.idProduct !=
 521                                 cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
 522                 /* The old original USB Earthmate seemed able to
 523                    handle GET_CONFIG requests; everything they've
 524                    produced since that time crashes if this command is
 525                    attempted :-( */
 526                 dev_dbg(&port->dev,
 527                         "%s - Marking this device as unsafe for GET_CONFIG commands\n",
 528                         __func__);
 529                 priv->get_cfg_unsafe = !0;
 530         }
 531
 532         return 0;
 533 }
 534
 535 static int cypress_hidcom_port_probe(struct usb_serial_port *port)
 536 {
 537         struct cypress_private *priv;
 538         int ret;
 539
 540         ret = cypress_generic_port_probe(port);
 541         if (ret) {
 542                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 543                 return ret;
 544         }
 545
 546         priv = usb_get_serial_port_data(port);
 547         priv->chiptype = CT_CYPHIDCOM;
 548
 549         return 0;
 550 }
 551
 552 static int cypress_ca42v2_port_probe(struct usb_serial_port *port)
 553 {
 554         struct cypress_private *priv;
 555         int ret;
 556
 557         ret = cypress_generic_port_probe(port);
 558         if (ret) {
 559                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 560                 return ret;
 561         }
 562
 563         priv = usb_get_serial_port_data(port);
 564         priv->chiptype = CT_CA42V2;
 565
 566         return 0;
 567 }
 568
 569 static int cypress_port_remove(struct usb_serial_port *port)
 570 {
 571         struct cypress_private *priv;
 572
 573         priv = usb_get_serial_port_data(port);
 574
 575         kfifo_free(&priv->write_fifo);
 576         kfree(priv);
 577
 578         return 0;
 579 }
 580
 581 static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
 582 {
 583         struct cypress_private *priv = usb_get_serial_port_data(port);
 584         struct usb_serial *serial = port->serial;
 585         unsigned long flags;
 586         int result = 0;
 587
 588         if (!priv->comm_is_ok)
 589                 return -EIO;
 590
 591         /* clear halts before open */
 592         usb_clear_halt(serial->dev, 0x81);
 593         usb_clear_halt(serial->dev, 0x02);
 594
 595         spin_lock_irqsave(&priv->lock, flags);
 596         /* reset read/write statistics */
 597         priv->bytes_in = 0;
 598         priv->bytes_out = 0;
 599         priv->cmd_count = 0;
 600         priv->rx_flags = 0;
 601         spin_unlock_irqrestore(&priv->lock, flags);
 602
 603         /* Set termios */
 604         cypress_send(port);
 605
 606         if (tty)
 607                 cypress_set_termios(tty, port, &priv->tmp_termios);
 608
 609         /* setup the port and start reading from the device */
 610         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 611                 usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 612                 port->interrupt_in_urb->transfer_buffer,
 613                 port->interrupt_in_urb->transfer_buffer_length,
 614                 cypress_read_int_callback, port, priv->read_urb_interval);
 615         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 616
 617         if (result) {
 618                 dev_err(&port->dev,
 619                         "%s - failed submitting read urb, error %d\n",
 620                                                         __func__, result);
 621                 cypress_set_dead(port);
 622         }
 623
 624         return result;
 625 } /* cypress_open */
 626
 627 static void cypress_dtr_rts(struct usb_serial_port *port, int on)
 628 {
 629         struct cypress_private *priv = usb_get_serial_port_data(port);
 630         /* drop dtr and rts */
 631         spin_lock_irq(&priv->lock);
 632         if (on == 0)
 633                 priv->line_control = 0;
 634         else
 635                 priv->line_control = CONTROL_DTR | CONTROL_RTS;
 636         priv->cmd_ctrl = 1;
 637         spin_unlock_irq(&priv->lock);
 638         cypress_write(NULL, port, NULL, 0);
 639 }
 640
 641 static void cypress_close(struct usb_serial_port *port)
 642 {
 643         struct cypress_private *priv = usb_get_serial_port_data(port);
 644         unsigned long flags;
 645
 646         spin_lock_irqsave(&priv->lock, flags);
 647         kfifo_reset_out(&priv->write_fifo);
 648         spin_unlock_irqrestore(&priv->lock, flags);
 649
 650         dev_dbg(&port->dev, "%s - stopping urbs\n", __func__);
 651         usb_kill_urb(port->interrupt_in_urb);
 652         usb_kill_urb(port->interrupt_out_urb);
 653
 654         if (stats)
 655                 dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
 656                         priv->bytes_in, priv->bytes_out, priv->cmd_count);
 657 } /* cypress_close */
 658
 659
 660 static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 661                                         const unsigned char *buf, int count)
 662 {
 663         struct cypress_private *priv = usb_get_serial_port_data(port);
 664
 665         dev_dbg(&port->dev, "%s - %d bytes\n", __func__, count);
 666
 667         /* line control commands, which need to be executed immediately,
 668            are not put into the buffer for obvious reasons.
 669          */
 670         if (priv->cmd_ctrl) {
 671                 count = 0;
 672                 goto finish;
 673         }
 674
 675         if (!count)
 676                 return count;
 677
 678         count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
 679
 680 finish:
 681         cypress_send(port);
 682
 683         return count;
 684 } /* cypress_write */
 685
 686
 687 static void cypress_send(struct usb_serial_port *port)
 688 {
 689         int count = 0, result, offset, actual_size;
 690         struct cypress_private *priv = usb_get_serial_port_data(port);
 691         struct device *dev = &port->dev;
 692         unsigned long flags;
 693
 694         if (!priv->comm_is_ok)
 695                 return;
 696
 697         dev_dbg(dev, "%s - interrupt out size is %d\n", __func__,
 698                 port->interrupt_out_size);
 699
 700         spin_lock_irqsave(&priv->lock, flags);
 701         if (priv->write_urb_in_use) {
 702                 dev_dbg(dev, "%s - can't write, urb in use\n", __func__);
 703                 spin_unlock_irqrestore(&priv->lock, flags);
 704                 return;
 705         }
 706         spin_unlock_irqrestore(&priv->lock, flags);
 707
 708         /* clear buffer */
 709         memset(port->interrupt_out_urb->transfer_buffer, 0,
 710                                                 port->interrupt_out_size);
 711
 712         spin_lock_irqsave(&priv->lock, flags);
 713         switch (priv->pkt_fmt) {
 714         default:
 715         case packet_format_1:
 716                 /* this is for the CY7C64013... */
 717                 offset = 2;
 718                 port->interrupt_out_buffer[0] = priv->line_control;
 719                 break;
 720         case packet_format_2:
 721                 /* this is for the CY7C63743... */
 722                 offset = 1;
 723                 port->interrupt_out_buffer[0] = priv->line_control;
 724                 break;
 725         }
 726
 727         if (priv->line_control & CONTROL_RESET)
 728                 priv->line_control &= ~CONTROL_RESET;
 729
 730         if (priv->cmd_ctrl) {
 731                 priv->cmd_count++;
 732                 dev_dbg(dev, "%s - line control command being issued\n", __func__);
 733                 spin_unlock_irqrestore(&priv->lock, flags);
 734                 goto send;
 735         } else
 736                 spin_unlock_irqrestore(&priv->lock, flags);
 737
 738         count = kfifo_out_locked(&priv->write_fifo,
 739                                         &port->interrupt_out_buffer[offset],
 740                                         port->interrupt_out_size - offset,
 741                                         &priv->lock);
 742         if (count == 0)
 743                 return;
 744
 745         switch (priv->pkt_fmt) {
 746         default:
 747         case packet_format_1:
 748                 port->interrupt_out_buffer[1] = count;
 749                 break;
 750         case packet_format_2:
 751                 port->interrupt_out_buffer[0] |= count;
 752         }
 753
 754         dev_dbg(dev, "%s - count is %d\n", __func__, count);
 755
 756 send:
 757         spin_lock_irqsave(&priv->lock, flags);
 758         priv->write_urb_in_use = 1;
 759         spin_unlock_irqrestore(&priv->lock, flags);
 760
 761         if (priv->cmd_ctrl)
 762                 actual_size = 1;
 763         else
 764                 actual_size = count +
 765                               (priv->pkt_fmt == packet_format_1 ? 2 : 1);
 766
 767         usb_serial_debug_data(dev, __func__, port->interrupt_out_size,
 768                               port->interrupt_out_urb->transfer_buffer);
 769
 770         usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
 771                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
 772                 port->interrupt_out_buffer, port->interrupt_out_size,
 773                 cypress_write_int_callback, port, priv->write_urb_interval);
 774         result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
 775         if (result) {
 776                 dev_err_console(port,
 777                                 "%s - failed submitting write urb, error %d\n",
 778                                                         __func__, result);
 779                 priv->write_urb_in_use = 0;
 780                 cypress_set_dead(port);
 781         }
 782
 783         spin_lock_irqsave(&priv->lock, flags);
 784         if (priv->cmd_ctrl)
 785                 priv->cmd_ctrl = 0;
 786
 787         /* do not count the line control and size bytes */
 788         priv->bytes_out += count;
 789         spin_unlock_irqrestore(&priv->lock, flags);
 790
 791         usb_serial_port_softint(port);
 792 } /* cypress_send */
 793
 794
 795 /* returns how much space is available in the soft buffer */
 796 static int cypress_write_room(struct tty_struct *tty)
 797 {
 798         struct usb_serial_port *port = tty->driver_data;
 799         struct cypress_private *priv = usb_get_serial_port_data(port);
 800         int room = 0;
 801         unsigned long flags;
 802
 803         spin_lock_irqsave(&priv->lock, flags);
 804         room = kfifo_avail(&priv->write_fifo);
 805         spin_unlock_irqrestore(&priv->lock, flags);
 806
 807         dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
 808         return room;
 809 }
 810
 811
 812 static int cypress_tiocmget(struct tty_struct *tty)
 813 {
 814         struct usb_serial_port *port = tty->driver_data;
 815         struct cypress_private *priv = usb_get_serial_port_data(port);
 816         __u8 status, control;
 817         unsigned int result = 0;
 818         unsigned long flags;
 819
 820         spin_lock_irqsave(&priv->lock, flags);
 821         control = priv->line_control;
 822         status = priv->current_status;
 823         spin_unlock_irqrestore(&priv->lock, flags);
 824
 825         result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
 826                 | ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
 827                 | ((status & UART_CTS)        ? TIOCM_CTS : 0)
 828                 | ((status & UART_DSR)        ? TIOCM_DSR : 0)
 829                 | ((status & UART_RI)         ? TIOCM_RI  : 0)
 830                 | ((status & UART_CD)         ? TIOCM_CD  : 0);
 831
 832         dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
 833
 834         return result;
 835 }
 836
 837
 838 static int cypress_tiocmset(struct tty_struct *tty,
 839                                unsigned int set, unsigned int clear)
 840 {
 841         struct usb_serial_port *port = tty->driver_data;
 842         struct cypress_private *priv = usb_get_serial_port_data(port);
 843         unsigned long flags;
 844
 845         spin_lock_irqsave(&priv->lock, flags);
 846         if (set & TIOCM_RTS)
 847                 priv->line_control |= CONTROL_RTS;
 848         if (set & TIOCM_DTR)
 849                 priv->line_control |= CONTROL_DTR;
 850         if (clear & TIOCM_RTS)
 851                 priv->line_control &= ~CONTROL_RTS;
 852         if (clear & TIOCM_DTR)
 853                 priv->line_control &= ~CONTROL_DTR;
 854         priv->cmd_ctrl = 1;
 855         spin_unlock_irqrestore(&priv->lock, flags);
 856
 857         return cypress_write(tty, port, NULL, 0);
 858 }
 859
 860 static void cypress_set_termios(struct tty_struct *tty,
 861         struct usb_serial_port *port, struct ktermios *old_termios)
 862 {
 863         struct cypress_private *priv = usb_get_serial_port_data(port);
 864         struct device *dev = &port->dev;
 865         int data_bits, stop_bits, parity_type, parity_enable;
 866         unsigned cflag, iflag;
 867         unsigned long flags;
 868         __u8 oldlines;
 869         int linechange = 0;
 870
 871         spin_lock_irqsave(&priv->lock, flags);
 872         /* We can't clean this one up as we don't know the device type
 873            early enough */
 874         if (!priv->termios_initialized) {
 875                 if (priv->chiptype == CT_EARTHMATE) {
 876                         tty->termios = tty_std_termios;
 877                         tty->termios.c_cflag = B4800 | CS8 | CREAD | HUPCL |
 878                                 CLOCAL;
 879                         tty->termios.c_ispeed = 4800;
 880                         tty->termios.c_ospeed = 4800;
 881                 } else if (priv->chiptype == CT_CYPHIDCOM) {
 882                         tty->termios = tty_std_termios;
 883                         tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
 884                                 CLOCAL;
 885                         tty->termios.c_ispeed = 9600;
 886                         tty->termios.c_ospeed = 9600;
 887                 } else if (priv->chiptype == CT_CA42V2) {
 888                         tty->termios = tty_std_termios;
 889                         tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
 890                                 CLOCAL;
 891                         tty->termios.c_ispeed = 9600;
 892                         tty->termios.c_ospeed = 9600;
 893                 }
 894                 priv->termios_initialized = 1;
 895         }
 896         spin_unlock_irqrestore(&priv->lock, flags);
 897
 898         /* Unsupported features need clearing */
 899         tty->termios.c_cflag &= ~(CMSPAR|CRTSCTS);
 900
 901         cflag = tty->termios.c_cflag;
 902         iflag = tty->termios.c_iflag;
 903
 904         /* check if there are new settings */
 905         if (old_termios) {
 906                 spin_lock_irqsave(&priv->lock, flags);
 907                 priv->tmp_termios = tty->termios;
 908                 spin_unlock_irqrestore(&priv->lock, flags);
 909         }
 910
 911         /* set number of data bits, parity, stop bits */
 912         /* when parity is disabled the parity type bit is ignored */
 913
 914         /* 1 means 2 stop bits, 0 means 1 stop bit */
 915         stop_bits = cflag & CSTOPB ? 1 : 0;
 916
 917         if (cflag & PARENB) {
 918                 parity_enable = 1;
 919                 /* 1 means odd parity, 0 means even parity */
 920                 parity_type = cflag & PARODD ? 1 : 0;
 921         } else
 922                 parity_enable = parity_type = 0;
 923
 924         switch (cflag & CSIZE) {
 925         case CS5:
 926                 data_bits = 0;
 927                 break;
 928         case CS6:
 929                 data_bits = 1;
 930                 break;
 931         case CS7:
 932                 data_bits = 2;
 933                 break;
 934         case CS8:
 935                 data_bits = 3;
 936                 break;
 937         default:
 938                 dev_err(dev, "%s - CSIZE was set, but not CS5-CS8\n", __func__);
 939                 data_bits = 3;
 940         }
 941         spin_lock_irqsave(&priv->lock, flags);
 942         oldlines = priv->line_control;
 943         if ((cflag & CBAUD) == B0) {
 944                 /* drop dtr and rts */
 945                 dev_dbg(dev, "%s - dropping the lines, baud rate 0bps\n", __func__);
 946                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 947         } else
 948                 priv->line_control = (CONTROL_DTR | CONTROL_RTS);
 949         spin_unlock_irqrestore(&priv->lock, flags);
 950
 951         dev_dbg(dev, "%s - sending %d stop_bits, %d parity_enable, %d parity_type, %d data_bits (+5)\n",
 952                 __func__, stop_bits, parity_enable, parity_type, data_bits);
 953
 954         cypress_serial_control(tty, port, tty_get_baud_rate(tty),
 955                         data_bits, stop_bits,
 956                         parity_enable, parity_type,
 957                         0, CYPRESS_SET_CONFIG);
 958
 959         /* we perform a CYPRESS_GET_CONFIG so that the current settings are
 960          * filled into the private structure this should confirm that all is
 961          * working if it returns what we just set */
 962         cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
 963
 964         /* Here we can define custom tty settings for devices; the main tty
 965          * termios flag base comes from empeg.c */
 966
 967         spin_lock_irqsave(&priv->lock, flags);
 968         if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
 969                 dev_dbg(dev, "Using custom termios settings for a baud rate of 4800bps.\n");
 970                 /* define custom termios settings for NMEA protocol */
 971
 972                 tty->termios.c_iflag /* input modes - */
 973                         &= ~(IGNBRK  /* disable ignore break */
 974                         | BRKINT     /* disable break causes interrupt */
 975                         | PARMRK     /* disable mark parity errors */
 976                         | ISTRIP     /* disable clear high bit of input char */
 977                         | INLCR      /* disable translate NL to CR */
 978                         | IGNCR      /* disable ignore CR */
 979                         | ICRNL      /* disable translate CR to NL */
 980                         | IXON);     /* disable enable XON/XOFF flow control */
 981
 982                 tty->termios.c_oflag /* output modes */
 983                         &= ~OPOST;    /* disable postprocess output char */
 984
 985                 tty->termios.c_lflag /* line discipline modes */
 986                         &= ~(ECHO     /* disable echo input characters */
 987                         | ECHONL      /* disable echo new line */
 988                         | ICANON      /* disable erase, kill, werase, and rprnt
 989                                          special characters */
 990                         | ISIG        /* disable interrupt, quit, and suspend
 991                                          special characters */
 992                         | IEXTEN);    /* disable non-POSIX special characters */
 993         } /* CT_CYPHIDCOM: Application should handle this for device */
 994
 995         linechange = (priv->line_control != oldlines);
 996         spin_unlock_irqrestore(&priv->lock, flags);
 997
 998         /* if necessary, set lines */
 999         if (linechange) {
1000                 priv->cmd_ctrl = 1;
1001                 cypress_write(tty, port, NULL, 0);
1002         }
1003 } /* cypress_set_termios */
1004
1005
1006 /* returns amount of data still left in soft buffer */
1007 static int cypress_chars_in_buffer(struct tty_struct *tty)
1008 {
1009         struct usb_serial_port *port = tty->driver_data;
1010         struct cypress_private *priv = usb_get_serial_port_data(port);
1011         int chars = 0;
1012         unsigned long flags;
1013
1014         spin_lock_irqsave(&priv->lock, flags);
1015         chars = kfifo_len(&priv->write_fifo);
1016         spin_unlock_irqrestore(&priv->lock, flags);
1017
1018         dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1019         return chars;
1020 }
1021
1022
1023 static void cypress_throttle(struct tty_struct *tty)
1024 {
1025         struct usb_serial_port *port = tty->driver_data;
1026         struct cypress_private *priv = usb_get_serial_port_data(port);
1027
1028         spin_lock_irq(&priv->lock);
1029         priv->rx_flags = THROTTLED;
1030         spin_unlock_irq(&priv->lock);
1031 }
1032
1033
1034 static void cypress_unthrottle(struct tty_struct *tty)
1035 {
1036         struct usb_serial_port *port = tty->driver_data;
1037         struct cypress_private *priv = usb_get_serial_port_data(port);
1038         int actually_throttled, result;
1039
1040         spin_lock_irq(&priv->lock);
1041         actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1042         priv->rx_flags = 0;
1043         spin_unlock_irq(&priv->lock);
1044
1045         if (!priv->comm_is_ok)
1046                 return;
1047
1048         if (actually_throttled) {
1049                 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1050                 if (result) {
1051                         dev_err(&port->dev, "%s - failed submitting read urb, "
1052                                         "error %d\n", __func__, result);
1053                         cypress_set_dead(port);
1054                 }
1055         }
1056 }
1057
1058
1059 static void cypress_read_int_callback(struct urb *urb)
1060 {
1061         struct usb_serial_port *port = urb->context;
1062         struct cypress_private *priv = usb_get_serial_port_data(port);
1063         struct device *dev = &urb->dev->dev;
1064         struct tty_struct *tty;
1065         unsigned char *data = urb->transfer_buffer;
1066         unsigned long flags;
1067         char tty_flag = TTY_NORMAL;
1068         int bytes = 0;
1069         int result;
1070         int i = 0;
1071         int status = urb->status;
1072
1073         switch (status) {
1074         case 0: /* success */
1075                 break;
1076         case -ECONNRESET:
1077         case -ENOENT:
1078         case -ESHUTDOWN:
1079                 /* precursor to disconnect so just go away */
1080                 return;
1081         case -EPIPE:
1082                 /* Can't call usb_clear_halt while in_interrupt */
1083                 /* FALLS THROUGH */
1084         default:
1085                 /* something ugly is going on... */
1086                 dev_err(dev, "%s - unexpected nonzero read status received: %d\n",
1087                         __func__, status);
1088                 cypress_set_dead(port);
1089                 return;
1090         }
1091
1092         spin_lock_irqsave(&priv->lock, flags);
1093         if (priv->rx_flags & THROTTLED) {
1094                 dev_dbg(dev, "%s - now throttling\n", __func__);
1095                 priv->rx_flags |= ACTUALLY_THROTTLED;
1096                 spin_unlock_irqrestore(&priv->lock, flags);
1097                 return;
1098         }
1099         spin_unlock_irqrestore(&priv->lock, flags);
1100
1101         tty = tty_port_tty_get(&port->port);
1102         if (!tty) {
1103                 dev_dbg(dev, "%s - bad tty pointer - exiting\n", __func__);
1104                 return;
1105         }
1106
1107         spin_lock_irqsave(&priv->lock, flags);
1108         result = urb->actual_length;
1109         switch (priv->pkt_fmt) {
1110         default:
1111         case packet_format_1:
1112                 /* This is for the CY7C64013... */
1113                 priv->current_status = data[0] & 0xF8;
1114                 bytes = data[1] + 2;
1115                 i = 2;
1116                 break;
1117         case packet_format_2:
1118                 /* This is for the CY7C63743... */
1119                 priv->current_status = data[0] & 0xF8;
1120                 bytes = (data[0] & 0x07) + 1;
1121                 i = 1;
1122                 break;
1123         }
1124         spin_unlock_irqrestore(&priv->lock, flags);
1125         if (result < bytes) {
1126                 dev_dbg(dev,
1127                         "%s - wrong packet size - received %d bytes but packet said %d bytes\n",
1128                         __func__, result, bytes);
1129                 goto continue_read;
1130         }
1131
1132         usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1133
1134         spin_lock_irqsave(&priv->lock, flags);
1135         /* check to see if status has changed */
1136         if (priv->current_status != priv->prev_status) {
1137                 u8 delta = priv->current_status ^ priv->prev_status;
1138
1139                 if (delta & UART_MSR_MASK) {
1140                         if (delta & UART_CTS)
1141                                 port->icount.cts++;
1142                         if (delta & UART_DSR)
1143                                 port->icount.dsr++;
1144                         if (delta & UART_RI)
1145                                 port->icount.rng++;
1146                         if (delta & UART_CD)
1147                                 port->icount.dcd++;
1148
1149                         wake_up_interruptible(&port->port.delta_msr_wait);
1150                 }
1151
1152                 priv->prev_status = priv->current_status;
1153         }
1154         spin_unlock_irqrestore(&priv->lock, flags);
1155
1156         /* hangup, as defined in acm.c... this might be a bad place for it
1157          * though */
1158         if (tty && !C_CLOCAL(tty) && !(priv->current_status & UART_CD)) {
1159                 dev_dbg(dev, "%s - calling hangup\n", __func__);
1160                 tty_hangup(tty);
1161                 goto continue_read;
1162         }
1163
1164         /* There is one error bit... I'm assuming it is a parity error
1165          * indicator as the generic firmware will set this bit to 1 if a
1166          * parity error occurs.
1167          * I can not find reference to any other error events. */
1168         spin_lock_irqsave(&priv->lock, flags);
1169         if (priv->current_status & CYP_ERROR) {
1170                 spin_unlock_irqrestore(&priv->lock, flags);
1171                 tty_flag = TTY_PARITY;
1172                 dev_dbg(dev, "%s - Parity Error detected\n", __func__);
1173         } else
1174                 spin_unlock_irqrestore(&priv->lock, flags);
1175
1176         /* process read if there is data other than line status */
1177         if (bytes > i) {
1178                 tty_insert_flip_string_fixed_flag(&port->port, data + i,
1179                                 tty_flag, bytes - i);
1180                 tty_flip_buffer_push(&port->port);
1181         }
1182
1183         spin_lock_irqsave(&priv->lock, flags);
1184         /* control and status byte(s) are also counted */
1185         priv->bytes_in += bytes;
1186         spin_unlock_irqrestore(&priv->lock, flags);
1187
1188 continue_read:
1189         tty_kref_put(tty);
1190
1191         /* Continue trying to always read */
1192
1193         if (priv->comm_is_ok) {
1194                 usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1195                                 usb_rcvintpipe(port->serial->dev,
1196                                         port->interrupt_in_endpointAddress),
1197                                 port->interrupt_in_urb->transfer_buffer,
1198                                 port->interrupt_in_urb->transfer_buffer_length,
1199                                 cypress_read_int_callback, port,
1200                                 priv->read_urb_interval);
1201                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1202                 if (result && result != -EPERM) {
1203                         dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
1204                                 __func__, result);
1205                         cypress_set_dead(port);
1206                 }
1207         }
1208 } /* cypress_read_int_callback */
1209
1210
1211 static void cypress_write_int_callback(struct urb *urb)
1212 {
1213         struct usb_serial_port *port = urb->context;
1214         struct cypress_private *priv = usb_get_serial_port_data(port);
1215         struct device *dev = &urb->dev->dev;
1216         int status = urb->status;
1217
1218         switch (status) {
1219         case 0:
1220                 /* success */
1221                 break;
1222         case -ECONNRESET:
1223         case -ENOENT:
1224         case -ESHUTDOWN:
1225                 /* this urb is terminated, clean up */
1226                 dev_dbg(dev, "%s - urb shutting down with status: %d\n",
1227                         __func__, status);
1228                 priv->write_urb_in_use = 0;
1229                 return;
1230         case -EPIPE:
1231                 /* Cannot call usb_clear_halt while in_interrupt */
1232                 /* FALLTHROUGH */
1233         default:
1234                 dev_err(dev, "%s - unexpected nonzero write status received: %d\n",
1235                         __func__, status);
1236                 cypress_set_dead(port);
1237                 break;
1238         }
1239         priv->write_urb_in_use = 0;
1240
1241         /* send any buffered data */
1242         cypress_send(port);
1243 }
1244
1245 module_usb_serial_driver(serial_drivers, id_table_combined);
1246
1247 MODULE_AUTHOR(DRIVER_AUTHOR);
1248 MODULE_DESCRIPTION(DRIVER_DESC);
1249 MODULE_LICENSE("GPL");
1250
1251 module_param(stats, bool, S_IRUGO | S_IWUSR);
1252 MODULE_PARM_DESC(stats, "Enable statistics or not");
1253 module_param(interval, int, S_IRUGO | S_IWUSR);
1254 MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1255 module_param(unstable_bauds, bool, S_IRUGO | S_IWUSR);
1256 MODULE_PARM_DESC(unstable_bauds, "Allow unstable baud rates");