kernel/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/slab.h>
  31 #include <linux/tty.h>
  32 #include <linux/tty_driver.h>
  33 #include <linux/tty_flip.h>
  34 #include <linux/module.h>
  35 #include <linux/moduleparam.h>
  36 #include <linux/spinlock.h>
  37 #include <linux/usb.h>
  38 #include <linux/usb/serial.h>
  39 #include <linux/serial.h>
  40 #include <linux/kfifo.h>
  41 #include <linux/delay.h>
  42 #include <linux/uaccess.h>
  43 #include <asm/unaligned.h>
  44
  45 #include "cypress_m8.h"
  46
  47
  48 static bool stats;
  49 static int interval;
  50 static bool unstable_bauds;
  51
  52 #define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
  53 #define DRIVER_DESC "Cypress USB to Serial Driver"
  54
  55 /* write buffer size defines */
  56 #define CYPRESS_BUF_SIZE        1024
  57
  58 static const struct usb_device_id id_table_earthmate[] = {
  59         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  60         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  61         { }                                             /* Terminating entry */
  62 };
  63
  64 static const struct usb_device_id id_table_cyphidcomrs232[] = {
  65         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  66         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  67         { USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
  68         { }                                             /* Terminating entry */
  69 };
  70
  71 static const struct usb_device_id id_table_nokiaca42v2[] = {
  72         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  73         { }                                             /* Terminating entry */
  74 };
  75
  76 static const struct usb_device_id id_table_combined[] = {
  77         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  78         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  79         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  80         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  81         { USB_DEVICE(VENDOR_ID_FRWD, PRODUCT_ID_CYPHIDCOM_FRWD) },
  82         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
  83         { }                                             /* Terminating entry */
  84 };
  85
  86 MODULE_DEVICE_TABLE(usb, id_table_combined);
  87
  88 enum packet_format {
  89         packet_format_1,  /* b0:status, b1:payload count */
  90         packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
  91 };
  92
  93 struct cypress_private {
  94         spinlock_t lock;                   /* private lock */
  95         int chiptype;                      /* identifier of device, for quirks/etc */
  96         int bytes_in;                      /* used for statistics */
  97         int bytes_out;                     /* used for statistics */
  98         int cmd_count;                     /* used for statistics */
  99         int cmd_ctrl;                      /* always set this to 1 before issuing a command */
 100         struct kfifo write_fifo;           /* write fifo */
 101         int write_urb_in_use;              /* write urb in use indicator */
 102         int write_urb_interval;            /* interval to use for write urb */
 103         int read_urb_interval;             /* interval to use for read urb */
 104         int comm_is_ok;                    /* true if communication is (still) ok */
 105         int termios_initialized;
 106         __u8 line_control;                 /* holds dtr / rts value */
 107         __u8 current_status;               /* received from last read - info on dsr,cts,cd,ri,etc */
 108         __u8 current_config;               /* stores the current configuration byte */
 109         __u8 rx_flags;                     /* throttling - used from whiteheat/ftdi_sio */
 110         enum packet_format pkt_fmt;        /* format to use for packet send / receive */
 111         int get_cfg_unsafe;                /* If true, the CYPRESS_GET_CONFIG is unsafe */
 112         int baud_rate;                     /* stores current baud rate in
 113                                               integer form */
 114         int isthrottled;                   /* if throttled, discard reads */
 115         char prev_status;                  /* used for TIOCMIWAIT */
 116         /* we pass a pointer to this as the argument sent to
 117            cypress_set_termios old_termios */
 118         struct ktermios tmp_termios;       /* stores the old termios settings */
 119 };
 120
 121 /* function prototypes for the Cypress USB to serial device */
 122 static int  cypress_earthmate_port_probe(struct usb_serial_port *port);
 123 static int  cypress_hidcom_port_probe(struct usb_serial_port *port);
 124 static int  cypress_ca42v2_port_probe(struct usb_serial_port *port);
 125 static int  cypress_port_remove(struct usb_serial_port *port);
 126 static int  cypress_open(struct tty_struct *tty, struct usb_serial_port *port);
 127 static void cypress_close(struct usb_serial_port *port);
 128 static void cypress_dtr_rts(struct usb_serial_port *port, int on);
 129 static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 130                         const unsigned char *buf, int count);
 131 static void cypress_send(struct usb_serial_port *port);
 132 static int  cypress_write_room(struct tty_struct *tty);
 133 static void cypress_set_termios(struct tty_struct *tty,
 134                         struct usb_serial_port *port, struct ktermios *old);
 135 static int  cypress_tiocmget(struct tty_struct *tty);
 136 static int  cypress_tiocmset(struct tty_struct *tty,
 137                         unsigned int set, unsigned int clear);
 138 static int  cypress_chars_in_buffer(struct tty_struct *tty);
 139 static void cypress_throttle(struct tty_struct *tty);
 140 static void cypress_unthrottle(struct tty_struct *tty);
 141 static void cypress_set_dead(struct usb_serial_port *port);
 142 static void cypress_read_int_callback(struct urb *urb);
 143 static void cypress_write_int_callback(struct urb *urb);
 144
 145 static struct usb_serial_driver cypress_earthmate_device = {
 146         .driver = {
 147                 .owner =                THIS_MODULE,
 148                 .name =                 "earthmate",
 149         },
 150         .description =                  "DeLorme Earthmate USB",
 151         .id_table =                     id_table_earthmate,
 152         .num_ports =                    1,
 153         .port_probe =                   cypress_earthmate_port_probe,
 154         .port_remove =                  cypress_port_remove,
 155         .open =                         cypress_open,
 156         .close =                        cypress_close,
 157         .dtr_rts =                      cypress_dtr_rts,
 158         .write =                        cypress_write,
 159         .write_room =                   cypress_write_room,
 160         .set_termios =                  cypress_set_termios,
 161         .tiocmget =                     cypress_tiocmget,
 162         .tiocmset =                     cypress_tiocmset,
 163         .tiocmiwait =                   usb_serial_generic_tiocmiwait,
 164         .chars_in_buffer =              cypress_chars_in_buffer,
 165         .throttle =                     cypress_throttle,
 166         .unthrottle =                   cypress_unthrottle,
 167         .read_int_callback =            cypress_read_int_callback,
 168         .write_int_callback =           cypress_write_int_callback,
 169 };
 170
 171 static struct usb_serial_driver cypress_hidcom_device = {
 172         .driver = {
 173                 .owner =                THIS_MODULE,
 174                 .name =                 "cyphidcom",
 175         },
 176         .description =                  "HID->COM RS232 Adapter",
 177         .id_table =                     id_table_cyphidcomrs232,
 178         .num_ports =                    1,
 179         .port_probe =                   cypress_hidcom_port_probe,
 180         .port_remove =                  cypress_port_remove,
 181         .open =                         cypress_open,
 182         .close =                        cypress_close,
 183         .dtr_rts =                      cypress_dtr_rts,
 184         .write =                        cypress_write,
 185         .write_room =                   cypress_write_room,
 186         .set_termios =                  cypress_set_termios,
 187         .tiocmget =                     cypress_tiocmget,
 188         .tiocmset =                     cypress_tiocmset,
 189         .tiocmiwait =                   usb_serial_generic_tiocmiwait,
 190         .chars_in_buffer =              cypress_chars_in_buffer,
 191         .throttle =                     cypress_throttle,
 192         .unthrottle =                   cypress_unthrottle,
 193         .read_int_callback =            cypress_read_int_callback,
 194         .write_int_callback =           cypress_write_int_callback,
 195 };
 196
 197 static struct usb_serial_driver cypress_ca42v2_device = {
 198         .driver = {
 199                 .owner =                THIS_MODULE,
 200                 .name =                 "nokiaca42v2",
 201         },
 202         .description =                  "Nokia CA-42 V2 Adapter",
 203         .id_table =                     id_table_nokiaca42v2,
 204         .num_ports =                    1,
 205         .port_probe =                   cypress_ca42v2_port_probe,
 206         .port_remove =                  cypress_port_remove,
 207         .open =                         cypress_open,
 208         .close =                        cypress_close,
 209         .dtr_rts =                      cypress_dtr_rts,
 210         .write =                        cypress_write,
 211         .write_room =                   cypress_write_room,
 212         .set_termios =                  cypress_set_termios,
 213         .tiocmget =                     cypress_tiocmget,
 214         .tiocmset =                     cypress_tiocmset,
 215         .tiocmiwait =                   usb_serial_generic_tiocmiwait,
 216         .chars_in_buffer =              cypress_chars_in_buffer,
 217         .throttle =                     cypress_throttle,
 218         .unthrottle =                   cypress_unthrottle,
 219         .read_int_callback =            cypress_read_int_callback,
 220         .write_int_callback =           cypress_write_int_callback,
 221 };
 222
 223 static struct usb_serial_driver * const serial_drivers[] = {
 224         &cypress_earthmate_device, &cypress_hidcom_device,
 225         &cypress_ca42v2_device, NULL
 226 };
 227
 228 /*****************************************************************************
 229  * Cypress serial helper functions
 230  *****************************************************************************/
 231
 232 /* FRWD Dongle hidcom needs to skip reset and speed checks */
 233 static inline bool is_frwd(struct usb_device *dev)
 234 {
 235         return ((le16_to_cpu(dev->descriptor.idVendor) == VENDOR_ID_FRWD) &&
 236                 (le16_to_cpu(dev->descriptor.idProduct) == PRODUCT_ID_CYPHIDCOM_FRWD));
 237 }
 238
 239 static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
 240 {
 241         struct cypress_private *priv;
 242         priv = usb_get_serial_port_data(port);
 243
 244         if (unstable_bauds)
 245                 return new_rate;
 246
 247         /* FRWD Dongle uses 115200 bps */
 248         if (is_frwd(port->serial->dev))
 249                 return new_rate;
 250
 251         /*
 252          * The general purpose firmware for the Cypress M8 allows for
 253          * a maximum speed of 57600bps (I have no idea whether DeLorme
 254          * chose to use the general purpose firmware or not), if you
 255          * need to modify this speed setting for your own project
 256          * please add your own chiptype and modify the code likewise.
 257          * The Cypress HID->COM device will work successfully up to
 258          * 115200bps (but the actual throughput is around 3kBps).
 259          */
 260         if (port->serial->dev->speed == USB_SPEED_LOW) {
 261                 /*
 262                  * Mike Isely <isely@pobox.com> 2-Feb-2008: The
 263                  * Cypress app note that describes this mechanism
 264                  * states the the low-speed part can't handle more
 265                  * than 800 bytes/sec, in which case 4800 baud is the
 266                  * safest speed for a part like that.
 267                  */
 268                 if (new_rate > 4800) {
 269                         dev_dbg(&port->dev,
 270                                 "%s - failed setting baud rate, device incapable speed %d\n",
 271                                 __func__, new_rate);
 272                         return -1;
 273                 }
 274         }
 275         switch (priv->chiptype) {
 276         case CT_EARTHMATE:
 277                 if (new_rate <= 600) {
 278                         /* 300 and 600 baud rates are supported under
 279                          * the generic firmware, but are not used with
 280                          * NMEA and SiRF protocols */
 281                         dev_dbg(&port->dev,
 282                                 "%s - failed setting baud rate, unsupported speed of %d on Earthmate GPS\n",
 283                                 __func__, new_rate);
 284                         return -1;
 285                 }
 286                 break;
 287         default:
 288                 break;
 289         }
 290         return new_rate;
 291 }
 292
 293
 294 /* This function can either set or retrieve the current serial line settings */
 295 static int cypress_serial_control(struct tty_struct *tty,
 296         struct usb_serial_port *port, speed_t baud_rate, int data_bits,
 297         int stop_bits, int parity_enable, int parity_type, int reset,
 298         int cypress_request_type)
 299 {
 300         int new_baudrate = 0, retval = 0, tries = 0;
 301         struct cypress_private *priv;
 302         struct device *dev = &port->dev;
 303         u8 *feature_buffer;
 304         const unsigned int feature_len = 5;
 305         unsigned long flags;
 306
 307         priv = usb_get_serial_port_data(port);
 308
 309         if (!priv->comm_is_ok)
 310                 return -ENODEV;
 311
 312         feature_buffer = kcalloc(feature_len, sizeof(u8), GFP_KERNEL);
 313         if (!feature_buffer)
 314                 return -ENOMEM;
 315
 316         switch (cypress_request_type) {
 317         case CYPRESS_SET_CONFIG:
 318                 /* 0 means 'Hang up' so doesn't change the true bit rate */
 319                 new_baudrate = priv->baud_rate;
 320                 if (baud_rate && baud_rate != priv->baud_rate) {
 321                         dev_dbg(dev, "%s - baud rate is changing\n", __func__);
 322                         retval = analyze_baud_rate(port, baud_rate);
 323                         if (retval >= 0) {
 324                                 new_baudrate = retval;
 325                                 dev_dbg(dev, "%s - New baud rate set to %d\n",
 326                                         __func__, new_baudrate);
 327                         }
 328                 }
 329                 dev_dbg(dev, "%s - baud rate is being sent as %d\n", __func__,
 330                         new_baudrate);
 331
 332                 /* fill the feature_buffer with new configuration */
 333                 put_unaligned_le32(new_baudrate, feature_buffer);
 334                 feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
 335                 /* 1 bit gap */
 336                 feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
 337                 feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
 338                 feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
 339                 /* 1 bit gap */
 340                 feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
 341
 342                 dev_dbg(dev, "%s - device is being sent this feature report:\n", __func__);
 343                 dev_dbg(dev, "%s - %02X - %02X - %02X - %02X - %02X\n", __func__,
 344                         feature_buffer[0], feature_buffer[1],
 345                         feature_buffer[2], feature_buffer[3],
 346                         feature_buffer[4]);
 347
 348                 do {
 349                         retval = usb_control_msg(port->serial->dev,
 350                                         usb_sndctrlpipe(port->serial->dev, 0),
 351                                         HID_REQ_SET_REPORT,
 352                                         USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 353                                         0x0300, 0, feature_buffer,
 354                                         feature_len, 500);
 355
 356                         if (tries++ >= 3)
 357                                 break;
 358
 359                 } while (retval != feature_len &&
 360                          retval != -ENODEV);
 361
 362                 if (retval != feature_len) {
 363                         dev_err(dev, "%s - failed sending serial line settings - %d\n",
 364                                 __func__, retval);
 365                         cypress_set_dead(port);
 366                 } else {
 367                         spin_lock_irqsave(&priv->lock, flags);
 368                         priv->baud_rate = new_baudrate;
 369                         priv->current_config = feature_buffer[4];
 370                         spin_unlock_irqrestore(&priv->lock, flags);
 371                         /* If we asked for a speed change encode it */
 372                         if (baud_rate)
 373                                 tty_encode_baud_rate(tty,
 374                                         new_baudrate, new_baudrate);
 375                 }
 376         break;
 377         case CYPRESS_GET_CONFIG:
 378                 if (priv->get_cfg_unsafe) {
 379                         /* Not implemented for this device,
 380                            and if we try to do it we're likely
 381                            to crash the hardware. */
 382                         retval = -ENOTTY;
 383                         goto out;
 384                 }
 385                 dev_dbg(dev, "%s - retreiving serial line settings\n", __func__);
 386                 do {
 387                         retval = usb_control_msg(port->serial->dev,
 388                                         usb_rcvctrlpipe(port->serial->dev, 0),
 389                                         HID_REQ_GET_REPORT,
 390                                         USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 391                                         0x0300, 0, feature_buffer,
 392                                         feature_len, 500);
 393
 394                         if (tries++ >= 3)
 395                                 break;
 396                 } while (retval != feature_len
 397                                                 && retval != -ENODEV);
 398
 399                 if (retval != feature_len) {
 400                         dev_err(dev, "%s - failed to retrieve serial line settings - %d\n",
 401                                 __func__, retval);
 402                         cypress_set_dead(port);
 403                         goto out;
 404                 } else {
 405                         spin_lock_irqsave(&priv->lock, flags);
 406                         /* store the config in one byte, and later
 407                            use bit masks to check values */
 408                         priv->current_config = feature_buffer[4];
 409                         priv->baud_rate = get_unaligned_le32(feature_buffer);
 410                         spin_unlock_irqrestore(&priv->lock, flags);
 411                 }
 412         }
 413         spin_lock_irqsave(&priv->lock, flags);
 414         ++priv->cmd_count;
 415         spin_unlock_irqrestore(&priv->lock, flags);
 416 out:
 417         kfree(feature_buffer);
 418         return retval;
 419 } /* cypress_serial_control */
 420
 421
 422 static void cypress_set_dead(struct usb_serial_port *port)
 423 {
 424         struct cypress_private *priv = usb_get_serial_port_data(port);
 425         unsigned long flags;
 426
 427         spin_lock_irqsave(&priv->lock, flags);
 428         if (!priv->comm_is_ok) {
 429                 spin_unlock_irqrestore(&priv->lock, flags);
 430                 return;
 431         }
 432         priv->comm_is_ok = 0;
 433         spin_unlock_irqrestore(&priv->lock, flags);
 434
 435         dev_err(&port->dev, "cypress_m8 suspending failing port %d - "
 436                 "interval might be too short\n", port->port_number);
 437 }
 438
 439
 440 /*****************************************************************************
 441  * Cypress serial driver functions
 442  *****************************************************************************/
 443
 444
 445 static int cypress_generic_port_probe(struct usb_serial_port *port)
 446 {
 447         struct usb_serial *serial = port->serial;
 448         struct cypress_private *priv;
 449
 450         if (!port->interrupt_out_urb || !port->interrupt_in_urb) {
 451                 dev_err(&port->dev, "required endpoint is missing\n");
 452                 return -ENODEV;
 453         }
 454
 455         priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL);
 456         if (!priv)
 457                 return -ENOMEM;
 458
 459         priv->comm_is_ok = !0;
 460         spin_lock_init(&priv->lock);
 461         if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
 462                 kfree(priv);
 463                 return -ENOMEM;
 464         }
 465
 466         /* Skip reset for FRWD device. It is a workaound:
 467            device hangs if it receives SET_CONFIGURE in Configured
 468            state. */
 469         if (!is_frwd(serial->dev))
 470                 usb_reset_configuration(serial->dev);
 471
 472         priv->cmd_ctrl = 0;
 473         priv->line_control = 0;
 474         priv->termios_initialized = 0;
 475         priv->rx_flags = 0;
 476         /* Default packet format setting is determined by packet size.
 477            Anything with a size larger then 9 must have a separate
 478            count field since the 3 bit count field is otherwise too
 479            small.  Otherwise we can use the slightly more compact
 480            format.  This is in accordance with the cypress_m8 serial
 481            converter app note. */
 482         if (port->interrupt_out_size > 9)
 483                 priv->pkt_fmt = packet_format_1;
 484         else
 485                 priv->pkt_fmt = packet_format_2;
 486
 487         if (interval > 0) {
 488                 priv->write_urb_interval = interval;
 489                 priv->read_urb_interval = interval;
 490                 dev_dbg(&port->dev, "%s - read & write intervals forced to %d\n",
 491                         __func__, interval);
 492         } else {
 493                 priv->write_urb_interval = port->interrupt_out_urb->interval;
 494                 priv->read_urb_interval = port->interrupt_in_urb->interval;
 495                 dev_dbg(&port->dev, "%s - intervals: read=%d write=%d\n",
 496                         __func__, priv->read_urb_interval,
 497                         priv->write_urb_interval);
 498         }
 499         usb_set_serial_port_data(port, priv);
 500
 501         port->port.drain_delay = 256;
 502
 503         return 0;
 504 }
 505
 506
 507 static int cypress_earthmate_port_probe(struct usb_serial_port *port)
 508 {
 509         struct usb_serial *serial = port->serial;
 510         struct cypress_private *priv;
 511         int ret;
 512
 513         ret = cypress_generic_port_probe(port);
 514         if (ret) {
 515                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 516                 return ret;
 517         }
 518
 519         priv = usb_get_serial_port_data(port);
 520         priv->chiptype = CT_EARTHMATE;
 521         /* All Earthmate devices use the separated-count packet
 522            format!  Idiotic. */
 523         priv->pkt_fmt = packet_format_1;
 524         if (serial->dev->descriptor.idProduct !=
 525                                 cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
 526                 /* The old original USB Earthmate seemed able to
 527                    handle GET_CONFIG requests; everything they've
 528                    produced since that time crashes if this command is
 529                    attempted :-( */
 530                 dev_dbg(&port->dev,
 531                         "%s - Marking this device as unsafe for GET_CONFIG commands\n",
 532                         __func__);
 533                 priv->get_cfg_unsafe = !0;
 534         }
 535
 536         return 0;
 537 }
 538
 539 static int cypress_hidcom_port_probe(struct usb_serial_port *port)
 540 {
 541         struct cypress_private *priv;
 542         int ret;
 543
 544         ret = cypress_generic_port_probe(port);
 545         if (ret) {
 546                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 547                 return ret;
 548         }
 549
 550         priv = usb_get_serial_port_data(port);
 551         priv->chiptype = CT_CYPHIDCOM;
 552
 553         return 0;
 554 }
 555
 556 static int cypress_ca42v2_port_probe(struct usb_serial_port *port)
 557 {
 558         struct cypress_private *priv;
 559         int ret;
 560
 561         ret = cypress_generic_port_probe(port);
 562         if (ret) {
 563                 dev_dbg(&port->dev, "%s - Failed setting up port\n", __func__);
 564                 return ret;
 565         }
 566
 567         priv = usb_get_serial_port_data(port);
 568         priv->chiptype = CT_CA42V2;
 569
 570         return 0;
 571 }
 572
 573 static int cypress_port_remove(struct usb_serial_port *port)
 574 {
 575         struct cypress_private *priv;
 576
 577         priv = usb_get_serial_port_data(port);
 578
 579         kfifo_free(&priv->write_fifo);
 580         kfree(priv);
 581
 582         return 0;
 583 }
 584
 585 static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
 586 {
 587         struct cypress_private *priv = usb_get_serial_port_data(port);
 588         struct usb_serial *serial = port->serial;
 589         unsigned long flags;
 590         int result = 0;
 591
 592         if (!priv->comm_is_ok)
 593                 return -EIO;
 594
 595         /* clear halts before open */
 596         usb_clear_halt(serial->dev, 0x81);
 597         usb_clear_halt(serial->dev, 0x02);
 598
 599         spin_lock_irqsave(&priv->lock, flags);
 600         /* reset read/write statistics */
 601         priv->bytes_in = 0;
 602         priv->bytes_out = 0;
 603         priv->cmd_count = 0;
 604         priv->rx_flags = 0;
 605         spin_unlock_irqrestore(&priv->lock, flags);
 606
 607         /* Set termios */
 608         cypress_send(port);
 609
 610         if (tty)
 611                 cypress_set_termios(tty, port, &priv->tmp_termios);
 612
 613         /* setup the port and start reading from the device */
 614         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 615                 usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 616                 port->interrupt_in_urb->transfer_buffer,
 617                 port->interrupt_in_urb->transfer_buffer_length,
 618                 cypress_read_int_callback, port, priv->read_urb_interval);
 619         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 620
 621         if (result) {
 622                 dev_err(&port->dev,
 623                         "%s - failed submitting read urb, error %d\n",
 624                                                         __func__, result);
 625                 cypress_set_dead(port);
 626         }
 627
 628         return result;
 629 } /* cypress_open */
 630
 631 static void cypress_dtr_rts(struct usb_serial_port *port, int on)
 632 {
 633         struct cypress_private *priv = usb_get_serial_port_data(port);
 634         /* drop dtr and rts */
 635         spin_lock_irq(&priv->lock);
 636         if (on == 0)
 637                 priv->line_control = 0;
 638         else
 639                 priv->line_control = CONTROL_DTR | CONTROL_RTS;
 640         priv->cmd_ctrl = 1;
 641         spin_unlock_irq(&priv->lock);
 642         cypress_write(NULL, port, NULL, 0);
 643 }
 644
 645 static void cypress_close(struct usb_serial_port *port)
 646 {
 647         struct cypress_private *priv = usb_get_serial_port_data(port);
 648         unsigned long flags;
 649
 650         spin_lock_irqsave(&priv->lock, flags);
 651         kfifo_reset_out(&priv->write_fifo);
 652         spin_unlock_irqrestore(&priv->lock, flags);
 653
 654         dev_dbg(&port->dev, "%s - stopping urbs\n", __func__);
 655         usb_kill_urb(port->interrupt_in_urb);
 656         usb_kill_urb(port->interrupt_out_urb);
 657
 658         if (stats)
 659                 dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
 660                         priv->bytes_in, priv->bytes_out, priv->cmd_count);
 661 } /* cypress_close */
 662
 663
 664 static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 665                                         const unsigned char *buf, int count)
 666 {
 667         struct cypress_private *priv = usb_get_serial_port_data(port);
 668
 669         dev_dbg(&port->dev, "%s - %d bytes\n", __func__, count);
 670
 671         /* line control commands, which need to be executed immediately,
 672            are not put into the buffer for obvious reasons.
 673          */
 674         if (priv->cmd_ctrl) {
 675                 count = 0;
 676                 goto finish;
 677         }
 678
 679         if (!count)
 680                 return count;
 681
 682         count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
 683
 684 finish:
 685         cypress_send(port);
 686
 687         return count;
 688 } /* cypress_write */
 689
 690
 691 static void cypress_send(struct usb_serial_port *port)
 692 {
 693         int count = 0, result, offset, actual_size;
 694         struct cypress_private *priv = usb_get_serial_port_data(port);
 695         struct device *dev = &port->dev;
 696         unsigned long flags;
 697
 698         if (!priv->comm_is_ok)
 699                 return;
 700
 701         dev_dbg(dev, "%s - interrupt out size is %d\n", __func__,
 702                 port->interrupt_out_size);
 703
 704         spin_lock_irqsave(&priv->lock, flags);
 705         if (priv->write_urb_in_use) {
 706                 dev_dbg(dev, "%s - can't write, urb in use\n", __func__);
 707                 spin_unlock_irqrestore(&priv->lock, flags);
 708                 return;
 709         }
 710         spin_unlock_irqrestore(&priv->lock, flags);
 711
 712         /* clear buffer */
 713         memset(port->interrupt_out_urb->transfer_buffer, 0,
 714                                                 port->interrupt_out_size);
 715
 716         spin_lock_irqsave(&priv->lock, flags);
 717         switch (priv->pkt_fmt) {
 718         default:
 719         case packet_format_1:
 720                 /* this is for the CY7C64013... */
 721                 offset = 2;
 722                 port->interrupt_out_buffer[0] = priv->line_control;
 723                 break;
 724         case packet_format_2:
 725                 /* this is for the CY7C63743... */
 726                 offset = 1;
 727                 port->interrupt_out_buffer[0] = priv->line_control;
 728                 break;
 729         }
 730
 731         if (priv->line_control & CONTROL_RESET)
 732                 priv->line_control &= ~CONTROL_RESET;
 733
 734         if (priv->cmd_ctrl) {
 735                 priv->cmd_count++;
 736                 dev_dbg(dev, "%s - line control command being issued\n", __func__);
 737                 spin_unlock_irqrestore(&priv->lock, flags);
 738                 goto send;
 739         } else
 740                 spin_unlock_irqrestore(&priv->lock, flags);
 741
 742         count = kfifo_out_locked(&priv->write_fifo,
 743                                         &port->interrupt_out_buffer[offset],
 744                                         port->interrupt_out_size - offset,
 745                                         &priv->lock);
 746         if (count == 0)
 747                 return;
 748
 749         switch (priv->pkt_fmt) {
 750         default:
 751         case packet_format_1:
 752                 port->interrupt_out_buffer[1] = count;
 753                 break;
 754         case packet_format_2:
 755                 port->interrupt_out_buffer[0] |= count;
 756         }
 757
 758         dev_dbg(dev, "%s - count is %d\n", __func__, count);
 759
 760 send:
 761         spin_lock_irqsave(&priv->lock, flags);
 762         priv->write_urb_in_use = 1;
 763         spin_unlock_irqrestore(&priv->lock, flags);
 764
 765         if (priv->cmd_ctrl)
 766                 actual_size = 1;
 767         else
 768                 actual_size = count +
 769                               (priv->pkt_fmt == packet_format_1 ? 2 : 1);
 770
 771         usb_serial_debug_data(dev, __func__, port->interrupt_out_size,
 772                               port->interrupt_out_urb->transfer_buffer);
 773
 774         usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
 775                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
 776                 port->interrupt_out_buffer, port->interrupt_out_size,
 777                 cypress_write_int_callback, port, priv->write_urb_interval);
 778         result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
 779         if (result) {
 780                 dev_err_console(port,
 781                                 "%s - failed submitting write urb, error %d\n",
 782                                                         __func__, result);
 783                 priv->write_urb_in_use = 0;
 784                 cypress_set_dead(port);
 785         }
 786
 787         spin_lock_irqsave(&priv->lock, flags);
 788         if (priv->cmd_ctrl)
 789                 priv->cmd_ctrl = 0;
 790
 791         /* do not count the line control and size bytes */
 792         priv->bytes_out += count;
 793         spin_unlock_irqrestore(&priv->lock, flags);
 794
 795         usb_serial_port_softint(port);
 796 } /* cypress_send */
 797
 798
 799 /* returns how much space is available in the soft buffer */
 800 static int cypress_write_room(struct tty_struct *tty)
 801 {
 802         struct usb_serial_port *port = tty->driver_data;
 803         struct cypress_private *priv = usb_get_serial_port_data(port);
 804         int room = 0;
 805         unsigned long flags;
 806
 807         spin_lock_irqsave(&priv->lock, flags);
 808         room = kfifo_avail(&priv->write_fifo);
 809         spin_unlock_irqrestore(&priv->lock, flags);
 810
 811         dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
 812         return room;
 813 }
 814
 815
 816 static int cypress_tiocmget(struct tty_struct *tty)
 817 {
 818         struct usb_serial_port *port = tty->driver_data;
 819         struct cypress_private *priv = usb_get_serial_port_data(port);
 820         __u8 status, control;
 821         unsigned int result = 0;
 822         unsigned long flags;
 823
 824         spin_lock_irqsave(&priv->lock, flags);
 825         control = priv->line_control;
 826         status = priv->current_status;
 827         spin_unlock_irqrestore(&priv->lock, flags);
 828
 829         result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
 830                 | ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
 831                 | ((status & UART_CTS)        ? TIOCM_CTS : 0)
 832                 | ((status & UART_DSR)        ? TIOCM_DSR : 0)
 833                 | ((status & UART_RI)         ? TIOCM_RI  : 0)
 834                 | ((status & UART_CD)         ? TIOCM_CD  : 0);
 835
 836         dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
 837
 838         return result;
 839 }
 840
 841
 842 static int cypress_tiocmset(struct tty_struct *tty,
 843                                unsigned int set, unsigned int clear)
 844 {
 845         struct usb_serial_port *port = tty->driver_data;
 846         struct cypress_private *priv = usb_get_serial_port_data(port);
 847         unsigned long flags;
 848
 849         spin_lock_irqsave(&priv->lock, flags);
 850         if (set & TIOCM_RTS)
 851                 priv->line_control |= CONTROL_RTS;
 852         if (set & TIOCM_DTR)
 853                 priv->line_control |= CONTROL_DTR;
 854         if (clear & TIOCM_RTS)
 855                 priv->line_control &= ~CONTROL_RTS;
 856         if (clear & TIOCM_DTR)
 857                 priv->line_control &= ~CONTROL_DTR;
 858         priv->cmd_ctrl = 1;
 859         spin_unlock_irqrestore(&priv->lock, flags);
 860
 861         return cypress_write(tty, port, NULL, 0);
 862 }
 863
 864 static void cypress_set_termios(struct tty_struct *tty,
 865         struct usb_serial_port *port, struct ktermios *old_termios)
 866 {
 867         struct cypress_private *priv = usb_get_serial_port_data(port);
 868         struct device *dev = &port->dev;
 869         int data_bits, stop_bits, parity_type, parity_enable;
 870         unsigned cflag, iflag;
 871         unsigned long flags;
 872         __u8 oldlines;
 873         int linechange = 0;
 874
 875         spin_lock_irqsave(&priv->lock, flags);
 876         /* We can't clean this one up as we don't know the device type
 877            early enough */
 878         if (!priv->termios_initialized) {
 879                 if (priv->chiptype == CT_EARTHMATE) {
 880                         tty->termios = tty_std_termios;
 881                         tty->termios.c_cflag = B4800 | CS8 | CREAD | HUPCL |
 882                                 CLOCAL;
 883                         tty->termios.c_ispeed = 4800;
 884                         tty->termios.c_ospeed = 4800;
 885                 } else if (priv->chiptype == CT_CYPHIDCOM) {
 886                         tty->termios = tty_std_termios;
 887                         tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
 888                                 CLOCAL;
 889                         tty->termios.c_ispeed = 9600;
 890                         tty->termios.c_ospeed = 9600;
 891                 } else if (priv->chiptype == CT_CA42V2) {
 892                         tty->termios = tty_std_termios;
 893                         tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
 894                                 CLOCAL;
 895                         tty->termios.c_ispeed = 9600;
 896                         tty->termios.c_ospeed = 9600;
 897                 }
 898                 priv->termios_initialized = 1;
 899         }
 900         spin_unlock_irqrestore(&priv->lock, flags);
 901
 902         /* Unsupported features need clearing */
 903         tty->termios.c_cflag &= ~(CMSPAR|CRTSCTS);
 904
 905         cflag = tty->termios.c_cflag;
 906         iflag = tty->termios.c_iflag;
 907
 908         /* check if there are new settings */
 909         if (old_termios) {
 910                 spin_lock_irqsave(&priv->lock, flags);
 911                 priv->tmp_termios = tty->termios;
 912                 spin_unlock_irqrestore(&priv->lock, flags);
 913         }
 914
 915         /* set number of data bits, parity, stop bits */
 916         /* when parity is disabled the parity type bit is ignored */
 917
 918         /* 1 means 2 stop bits, 0 means 1 stop bit */
 919         stop_bits = cflag & CSTOPB ? 1 : 0;
 920
 921         if (cflag & PARENB) {
 922                 parity_enable = 1;
 923                 /* 1 means odd parity, 0 means even parity */
 924                 parity_type = cflag & PARODD ? 1 : 0;
 925         } else
 926                 parity_enable = parity_type = 0;
 927
 928         switch (cflag & CSIZE) {
 929         case CS5:
 930                 data_bits = 0;
 931                 break;
 932         case CS6:
 933                 data_bits = 1;
 934                 break;
 935         case CS7:
 936                 data_bits = 2;
 937                 break;
 938         case CS8:
 939                 data_bits = 3;
 940                 break;
 941         default:
 942                 dev_err(dev, "%s - CSIZE was set, but not CS5-CS8\n", __func__);
 943                 data_bits = 3;
 944         }
 945         spin_lock_irqsave(&priv->lock, flags);
 946         oldlines = priv->line_control;
 947         if ((cflag & CBAUD) == B0) {
 948                 /* drop dtr and rts */
 949                 dev_dbg(dev, "%s - dropping the lines, baud rate 0bps\n", __func__);
 950                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 951         } else
 952                 priv->line_control = (CONTROL_DTR | CONTROL_RTS);
 953         spin_unlock_irqrestore(&priv->lock, flags);
 954
 955         dev_dbg(dev, "%s - sending %d stop_bits, %d parity_enable, %d parity_type, %d data_bits (+5)\n",
 956                 __func__, stop_bits, parity_enable, parity_type, data_bits);
 957
 958         cypress_serial_control(tty, port, tty_get_baud_rate(tty),
 959                         data_bits, stop_bits,
 960                         parity_enable, parity_type,
 961                         0, CYPRESS_SET_CONFIG);
 962
 963         /* we perform a CYPRESS_GET_CONFIG so that the current settings are
 964          * filled into the private structure this should confirm that all is
 965          * working if it returns what we just set */
 966         cypress_serial_control(tty, port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
 967
 968         /* Here we can define custom tty settings for devices; the main tty
 969          * termios flag base comes from empeg.c */
 970
 971         spin_lock_irqsave(&priv->lock, flags);
 972         if (priv->chiptype == CT_EARTHMATE && priv->baud_rate == 4800) {
 973                 dev_dbg(dev, "Using custom termios settings for a baud rate of 4800bps.\n");
 974                 /* define custom termios settings for NMEA protocol */
 975
 976                 tty->termios.c_iflag /* input modes - */
 977                         &= ~(IGNBRK  /* disable ignore break */
 978                         | BRKINT     /* disable break causes interrupt */
 979                         | PARMRK     /* disable mark parity errors */
 980                         | ISTRIP     /* disable clear high bit of input char */
 981                         | INLCR      /* disable translate NL to CR */
 982                         | IGNCR      /* disable ignore CR */
 983                         | ICRNL      /* disable translate CR to NL */
 984                         | IXON);     /* disable enable XON/XOFF flow control */
 985
 986                 tty->termios.c_oflag /* output modes */
 987                         &= ~OPOST;    /* disable postprocess output char */
 988
 989                 tty->termios.c_lflag /* line discipline modes */
 990                         &= ~(ECHO     /* disable echo input characters */
 991                         | ECHONL      /* disable echo new line */
 992                         | ICANON      /* disable erase, kill, werase, and rprnt
 993                                          special characters */
 994                         | ISIG        /* disable interrupt, quit, and suspend
 995                                          special characters */
 996                         | IEXTEN);    /* disable non-POSIX special characters */
 997         } /* CT_CYPHIDCOM: Application should handle this for device */
 998
 999         linechange = (priv->line_control != oldlines);
1000         spin_unlock_irqrestore(&priv->lock, flags);
1001
1002         /* if necessary, set lines */
1003         if (linechange) {
1004                 priv->cmd_ctrl = 1;
1005                 cypress_write(tty, port, NULL, 0);
1006         }
1007 } /* cypress_set_termios */
1008
1009
1010 /* returns amount of data still left in soft buffer */
1011 static int cypress_chars_in_buffer(struct tty_struct *tty)
1012 {
1013         struct usb_serial_port *port = tty->driver_data;
1014         struct cypress_private *priv = usb_get_serial_port_data(port);
1015         int chars = 0;
1016         unsigned long flags;
1017
1018         spin_lock_irqsave(&priv->lock, flags);
1019         chars = kfifo_len(&priv->write_fifo);
1020         spin_unlock_irqrestore(&priv->lock, flags);
1021
1022         dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1023         return chars;
1024 }
1025
1026
1027 static void cypress_throttle(struct tty_struct *tty)
1028 {
1029         struct usb_serial_port *port = tty->driver_data;
1030         struct cypress_private *priv = usb_get_serial_port_data(port);
1031
1032         spin_lock_irq(&priv->lock);
1033         priv->rx_flags = THROTTLED;
1034         spin_unlock_irq(&priv->lock);
1035 }
1036
1037
1038 static void cypress_unthrottle(struct tty_struct *tty)
1039 {
1040         struct usb_serial_port *port = tty->driver_data;
1041         struct cypress_private *priv = usb_get_serial_port_data(port);
1042         int actually_throttled, result;
1043
1044         spin_lock_irq(&priv->lock);
1045         actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1046         priv->rx_flags = 0;
1047         spin_unlock_irq(&priv->lock);
1048
1049         if (!priv->comm_is_ok)
1050                 return;
1051
1052         if (actually_throttled) {
1053                 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
1054                 if (result) {
1055                         dev_err(&port->dev, "%s - failed submitting read urb, "
1056                                         "error %d\n", __func__, result);
1057                         cypress_set_dead(port);
1058                 }
1059         }
1060 }
1061
1062
1063 static void cypress_read_int_callback(struct urb *urb)
1064 {
1065         struct usb_serial_port *port = urb->context;
1066         struct cypress_private *priv = usb_get_serial_port_data(port);
1067         struct device *dev = &urb->dev->dev;
1068         struct tty_struct *tty;
1069         unsigned char *data = urb->transfer_buffer;
1070         unsigned long flags;
1071         char tty_flag = TTY_NORMAL;
1072         int havedata = 0;
1073         int bytes = 0;
1074         int result;
1075         int i = 0;
1076         int status = urb->status;
1077
1078         switch (status) {
1079         case 0: /* success */
1080                 break;
1081         case -ECONNRESET:
1082         case -ENOENT:
1083         case -ESHUTDOWN:
1084                 /* precursor to disconnect so just go away */
1085                 return;
1086         case -EPIPE:
1087                 /* Can't call usb_clear_halt while in_interrupt */
1088                 /* FALLS THROUGH */
1089         default:
1090                 /* something ugly is going on... */
1091                 dev_err(dev, "%s - unexpected nonzero read status received: %d\n",
1092                         __func__, status);
1093                 cypress_set_dead(port);
1094                 return;
1095         }
1096
1097         spin_lock_irqsave(&priv->lock, flags);
1098         if (priv->rx_flags & THROTTLED) {
1099                 dev_dbg(dev, "%s - now throttling\n", __func__);
1100                 priv->rx_flags |= ACTUALLY_THROTTLED;
1101                 spin_unlock_irqrestore(&priv->lock, flags);
1102                 return;
1103         }
1104         spin_unlock_irqrestore(&priv->lock, flags);
1105
1106         tty = tty_port_tty_get(&port->port);
1107         if (!tty) {
1108                 dev_dbg(dev, "%s - bad tty pointer - exiting\n", __func__);
1109                 return;
1110         }
1111
1112         spin_lock_irqsave(&priv->lock, flags);
1113         result = urb->actual_length;
1114         switch (priv->pkt_fmt) {
1115         default:
1116         case packet_format_1:
1117                 /* This is for the CY7C64013... */
1118                 priv->current_status = data[0] & 0xF8;
1119                 bytes = data[1] + 2;
1120                 i = 2;
1121                 if (bytes > 2)
1122                         havedata = 1;
1123                 break;
1124         case packet_format_2:
1125                 /* This is for the CY7C63743... */
1126                 priv->current_status = data[0] & 0xF8;
1127                 bytes = (data[0] & 0x07) + 1;
1128                 i = 1;
1129                 if (bytes > 1)
1130                         havedata = 1;
1131                 break;
1132         }
1133         spin_unlock_irqrestore(&priv->lock, flags);
1134         if (result < bytes) {
1135                 dev_dbg(dev,
1136                         "%s - wrong packet size - received %d bytes but packet said %d bytes\n",
1137                         __func__, result, bytes);
1138                 goto continue_read;
1139         }
1140
1141         usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
1142
1143         spin_lock_irqsave(&priv->lock, flags);
1144         /* check to see if status has changed */
1145         if (priv->current_status != priv->prev_status) {
1146                 u8 delta = priv->current_status ^ priv->prev_status;
1147
1148                 if (delta & UART_MSR_MASK) {
1149                         if (delta & UART_CTS)
1150                                 port->icount.cts++;
1151                         if (delta & UART_DSR)
1152                                 port->icount.dsr++;
1153                         if (delta & UART_RI)
1154                                 port->icount.rng++;
1155                         if (delta & UART_CD)
1156                                 port->icount.dcd++;
1157
1158                         wake_up_interruptible(&port->port.delta_msr_wait);
1159                 }
1160
1161                 priv->prev_status = priv->current_status;
1162         }
1163         spin_unlock_irqrestore(&priv->lock, flags);
1164
1165         /* hangup, as defined in acm.c... this might be a bad place for it
1166          * though */
1167         if (tty && !(tty->termios.c_cflag & CLOCAL) &&
1168                         !(priv->current_status & UART_CD)) {
1169                 dev_dbg(dev, "%s - calling hangup\n", __func__);
1170                 tty_hangup(tty);
1171                 goto continue_read;
1172         }
1173
1174         /* There is one error bit... I'm assuming it is a parity error
1175          * indicator as the generic firmware will set this bit to 1 if a
1176          * parity error occurs.
1177          * I can not find reference to any other error events. */
1178         spin_lock_irqsave(&priv->lock, flags);
1179         if (priv->current_status & CYP_ERROR) {
1180                 spin_unlock_irqrestore(&priv->lock, flags);
1181                 tty_flag = TTY_PARITY;
1182                 dev_dbg(dev, "%s - Parity Error detected\n", __func__);
1183         } else
1184                 spin_unlock_irqrestore(&priv->lock, flags);
1185
1186         /* process read if there is data other than line status */
1187         if (bytes > i) {
1188                 tty_insert_flip_string_fixed_flag(&port->port, data + i,
1189                                 tty_flag, bytes - i);
1190                 tty_flip_buffer_push(&port->port);
1191         }
1192
1193         spin_lock_irqsave(&priv->lock, flags);
1194         /* control and status byte(s) are also counted */
1195         priv->bytes_in += bytes;
1196         spin_unlock_irqrestore(&priv->lock, flags);
1197
1198 continue_read:
1199         tty_kref_put(tty);
1200
1201         /* Continue trying to always read */
1202
1203         if (priv->comm_is_ok) {
1204                 usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1205                                 usb_rcvintpipe(port->serial->dev,
1206                                         port->interrupt_in_endpointAddress),
1207                                 port->interrupt_in_urb->transfer_buffer,
1208                                 port->interrupt_in_urb->transfer_buffer_length,
1209                                 cypress_read_int_callback, port,
1210                                 priv->read_urb_interval);
1211                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1212                 if (result && result != -EPERM) {
1213                         dev_err(dev, "%s - failed resubmitting read urb, error %d\n",
1214                                 __func__, result);
1215                         cypress_set_dead(port);
1216                 }
1217         }
1218 } /* cypress_read_int_callback */
1219
1220
1221 static void cypress_write_int_callback(struct urb *urb)
1222 {
1223         struct usb_serial_port *port = urb->context;
1224         struct cypress_private *priv = usb_get_serial_port_data(port);
1225         struct device *dev = &urb->dev->dev;
1226         int status = urb->status;
1227
1228         switch (status) {
1229         case 0:
1230                 /* success */
1231                 break;
1232         case -ECONNRESET:
1233         case -ENOENT:
1234         case -ESHUTDOWN:
1235                 /* this urb is terminated, clean up */
1236                 dev_dbg(dev, "%s - urb shutting down with status: %d\n",
1237                         __func__, status);
1238                 priv->write_urb_in_use = 0;
1239                 return;
1240         case -EPIPE:
1241                 /* Cannot call usb_clear_halt while in_interrupt */
1242                 /* FALLTHROUGH */
1243         default:
1244                 dev_err(dev, "%s - unexpected nonzero write status received: %d\n",
1245                         __func__, status);
1246                 cypress_set_dead(port);
1247                 break;
1248         }
1249         priv->write_urb_in_use = 0;
1250
1251         /* send any buffered data */
1252         cypress_send(port);
1253 }
1254
1255 module_usb_serial_driver(serial_drivers, id_table_combined);
1256
1257 MODULE_AUTHOR(DRIVER_AUTHOR);
1258 MODULE_DESCRIPTION(DRIVER_DESC);
1259 MODULE_LICENSE("GPL");
1260
1261 module_param(stats, bool, S_IRUGO | S_IWUSR);
1262 MODULE_PARM_DESC(stats, "Enable statistics or not");
1263 module_param(interval, int, S_IRUGO | S_IWUSR);
1264 MODULE_PARM_DESC(interval, "Overrides interrupt interval");
1265 module_param(unstable_bauds, bool, S_IRUGO | S_IWUSR);
1266 MODULE_PARM_DESC(unstable_bauds, "Allow unstable baud rates");