drivers/usb/serial/pl2303.c

   1 /*
   2  * Prolific PL2303 USB to serial adaptor driver
   3  *
   4  * Copyright (C) 2001-2007 Greg Kroah-Hartman (greg@kroah.com)
   5  * Copyright (C) 2003 IBM Corp.
   6  *
   7  * Original driver for 2.2.x by anonymous
   8  *
   9  *      This program is free software; you can redistribute it and/or
  10  *      modify it under the terms of the GNU General Public License version
  11  *      2 as published by the Free Software Foundation.
  12  *
  13  * See Documentation/usb/usb-serial.txt for more information on using this
  14  * driver
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/errno.h>
  19 #include <linux/init.h>
  20 #include <linux/slab.h>
  21 #include <linux/tty.h>
  22 #include <linux/tty_driver.h>
  23 #include <linux/tty_flip.h>
  24 #include <linux/serial.h>
  25 #include <linux/module.h>
  26 #include <linux/moduleparam.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/uaccess.h>
  29 #include <linux/usb.h>
  30 #include <linux/usb/serial.h>
  31 #include <asm/unaligned.h>
  32 #include "pl2303.h"
  33
  34
  35 #define PL2303_QUIRK_UART_STATE_IDX0            BIT(0)
  36 #define PL2303_QUIRK_LEGACY                     BIT(1)
  37
  38 static const struct usb_device_id id_table[] = {
  39         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },
  40         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
  41         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
  42         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
  43         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_PHAROS) },
  44         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ALDIGA) },
  45         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MMX) },
  46         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GPRS) },
  47         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_HCR331) },
  48         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MOTOROLA) },
  49         { USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
  50         { USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID_RSAQ5) },
  51         { USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID) },
  52         { USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
  53         { USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
  54         { USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
  55         { USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
  56         { USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
  57         { USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
  58         { USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
  59         { USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
  60         { USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
  61         { USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
  62         { USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
  63         { USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
  64         { USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_PRODUCT_ID) },
  65         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1),
  66                 .driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
  67         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65),
  68                 .driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
  69         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75),
  70                 .driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
  71         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81) },
  72         { USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
  73         { USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
  74         { USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
  75         { USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
  76         { USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
  77         { USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
  78         { USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
  79         { USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
  80         { USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
  81         { USB_DEVICE(ALCOR_VENDOR_ID, ALCOR_PRODUCT_ID) },
  82         { USB_DEVICE(WS002IN_VENDOR_ID, WS002IN_PRODUCT_ID) },
  83         { USB_DEVICE(COREGA_VENDOR_ID, COREGA_PRODUCT_ID) },
  84         { USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
  85         { USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
  86         { USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
  87         { USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
  88         { USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
  89         { USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
  90         { USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
  91         { USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
  92         { USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
  93         { }                                     /* Terminating entry */
  94 };
  95
  96 MODULE_DEVICE_TABLE(usb, id_table);
  97
  98 #define SET_LINE_REQUEST_TYPE           0x21
  99 #define SET_LINE_REQUEST                0x20
 100
 101 #define SET_CONTROL_REQUEST_TYPE        0x21
 102 #define SET_CONTROL_REQUEST             0x22
 103 #define CONTROL_DTR                     0x01
 104 #define CONTROL_RTS                     0x02
 105
 106 #define BREAK_REQUEST_TYPE              0x21
 107 #define BREAK_REQUEST                   0x23
 108 #define BREAK_ON                        0xffff
 109 #define BREAK_OFF                       0x0000
 110
 111 #define GET_LINE_REQUEST_TYPE           0xa1
 112 #define GET_LINE_REQUEST                0x21
 113
 114 #define VENDOR_WRITE_REQUEST_TYPE       0x40
 115 #define VENDOR_WRITE_REQUEST            0x01
 116
 117 #define VENDOR_READ_REQUEST_TYPE        0xc0
 118 #define VENDOR_READ_REQUEST             0x01
 119
 120 #define UART_STATE_INDEX                8
 121 #define UART_STATE_MSR_MASK             0x8b
 122 #define UART_STATE_TRANSIENT_MASK       0x74
 123 #define UART_DCD                        0x01
 124 #define UART_DSR                        0x02
 125 #define UART_BREAK_ERROR                0x04
 126 #define UART_RING                       0x08
 127 #define UART_FRAME_ERROR                0x10
 128 #define UART_PARITY_ERROR               0x20
 129 #define UART_OVERRUN_ERROR              0x40
 130 #define UART_CTS                        0x80
 131
 132
 133 enum pl2303_type {
 134         TYPE_01,        /* Type 0 and 1 (difference unknown) */
 135         TYPE_HX,        /* HX version of the pl2303 chip */
 136         TYPE_COUNT
 137 };
 138
 139 struct pl2303_type_data {
 140         speed_t max_baud_rate;
 141         unsigned long quirks;
 142 };
 143
 144 struct pl2303_serial_private {
 145         const struct pl2303_type_data *type;
 146         unsigned long quirks;
 147 };
 148
 149 struct pl2303_private {
 150         spinlock_t lock;
 151         u8 line_control;
 152         u8 line_status;
 153
 154         u8 line_settings[7];
 155 };
 156
 157 static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
 158         [TYPE_01] = {
 159                 .max_baud_rate =        1228800,
 160                 .quirks =               PL2303_QUIRK_LEGACY,
 161         },
 162 };
 163
 164 static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
 165                                                         unsigned char buf[1])
 166 {
 167         struct device *dev = &serial->interface->dev;
 168         int res;
 169
 170         res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 171                         VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
 172                         value, 0, buf, 1, 100);
 173         if (res != 1) {
 174                 dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
 175                                                                 value, res);
 176                 if (res >= 0)
 177                         res = -EIO;
 178
 179                 return res;
 180         }
 181
 182         dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
 183
 184         return 0;
 185 }
 186
 187 static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
 188 {
 189         struct device *dev = &serial->interface->dev;
 190         int res;
 191
 192         dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
 193
 194         res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 195                         VENDOR_WRITE_REQUEST, VENDOR_WRITE_REQUEST_TYPE,
 196                         value, index, NULL, 0, 100);
 197         if (res) {
 198                 dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
 199                                                                 value, res);
 200                 return res;
 201         }
 202
 203         return 0;
 204 }
 205
 206 static int pl2303_probe(struct usb_serial *serial,
 207                                         const struct usb_device_id *id)
 208 {
 209         usb_set_serial_data(serial, (void *)id->driver_info);
 210
 211         return 0;
 212 }
 213
 214 static int pl2303_startup(struct usb_serial *serial)
 215 {
 216         struct pl2303_serial_private *spriv;
 217         enum pl2303_type type = TYPE_01;
 218         unsigned char *buf;
 219
 220         spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
 221         if (!spriv)
 222                 return -ENOMEM;
 223
 224         buf = kmalloc(1, GFP_KERNEL);
 225         if (!buf) {
 226                 kfree(spriv);
 227                 return -ENOMEM;
 228         }
 229
 230         if (serial->dev->descriptor.bDeviceClass == 0x02)
 231                 type = TYPE_01;         /* type 0 */
 232         else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
 233                 type = TYPE_HX;
 234         else if (serial->dev->descriptor.bDeviceClass == 0x00)
 235                 type = TYPE_01;         /* type 1 */
 236         else if (serial->dev->descriptor.bDeviceClass == 0xFF)
 237                 type = TYPE_01;         /* type 1 */
 238         dev_dbg(&serial->interface->dev, "device type: %d\n", type);
 239
 240         spriv->type = &pl2303_type_data[type];
 241         spriv->quirks = (unsigned long)usb_get_serial_data(serial);
 242         spriv->quirks |= spriv->type->quirks;
 243
 244         usb_set_serial_data(serial, spriv);
 245
 246         pl2303_vendor_read(serial, 0x8484, buf);
 247         pl2303_vendor_write(serial, 0x0404, 0);
 248         pl2303_vendor_read(serial, 0x8484, buf);
 249         pl2303_vendor_read(serial, 0x8383, buf);
 250         pl2303_vendor_read(serial, 0x8484, buf);
 251         pl2303_vendor_write(serial, 0x0404, 1);
 252         pl2303_vendor_read(serial, 0x8484, buf);
 253         pl2303_vendor_read(serial, 0x8383, buf);
 254         pl2303_vendor_write(serial, 0, 1);
 255         pl2303_vendor_write(serial, 1, 0);
 256         if (spriv->quirks & PL2303_QUIRK_LEGACY)
 257                 pl2303_vendor_write(serial, 2, 0x24);
 258         else
 259                 pl2303_vendor_write(serial, 2, 0x44);
 260
 261         kfree(buf);
 262
 263         return 0;
 264 }
 265
 266 static void pl2303_release(struct usb_serial *serial)
 267 {
 268         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 269
 270         kfree(spriv);
 271 }
 272
 273 static int pl2303_port_probe(struct usb_serial_port *port)
 274 {
 275         struct pl2303_private *priv;
 276
 277         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 278         if (!priv)
 279                 return -ENOMEM;
 280
 281         spin_lock_init(&priv->lock);
 282
 283         usb_set_serial_port_data(port, priv);
 284
 285         port->port.drain_delay = 256;
 286
 287         return 0;
 288 }
 289
 290 static int pl2303_port_remove(struct usb_serial_port *port)
 291 {
 292         struct pl2303_private *priv = usb_get_serial_port_data(port);
 293
 294         kfree(priv);
 295
 296         return 0;
 297 }
 298
 299 static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
 300 {
 301         struct usb_device *dev = port->serial->dev;
 302         int retval;
 303
 304         dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
 305
 306         retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 307                                  SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
 308                                  value, 0, NULL, 0, 100);
 309         if (retval)
 310                 dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
 311
 312         return retval;
 313 }
 314
 315 /*
 316  * Returns the nearest supported baud rate that can be set directly without
 317  * using divisors.
 318  */
 319 static speed_t pl2303_get_supported_baud_rate(speed_t baud)
 320 {
 321         static const speed_t baud_sup[] = {
 322                 75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
 323                 14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
 324                 614400, 921600, 1228800, 2457600, 3000000, 6000000
 325         };
 326
 327         unsigned i;
 328
 329         for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
 330                 if (baud_sup[i] > baud)
 331                         break;
 332         }
 333
 334         if (i == ARRAY_SIZE(baud_sup))
 335                 baud = baud_sup[i - 1];
 336         else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
 337                 baud = baud_sup[i - 1];
 338         else
 339                 baud = baud_sup[i];
 340
 341         return baud;
 342 }
 343
 344 /*
 345  * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
 346  *       use 9600 baud.
 347  */
 348 static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
 349                                                                 speed_t baud)
 350 {
 351         put_unaligned_le32(baud, buf);
 352
 353         return baud;
 354 }
 355
 356 static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
 357                                                                 speed_t baud)
 358 {
 359         unsigned int tmp;
 360
 361         /*
 362          * Apparently the formula is:
 363          * baudrate = 12M * 32 / (2^buf[1]) / buf[0]
 364          */
 365         tmp = 12000000 * 32 / baud;
 366         buf[3] = 0x80;
 367         buf[2] = 0;
 368         buf[1] = (tmp >= 256);
 369         while (tmp >= 256) {
 370                 tmp >>= 2;
 371                 buf[1] <<= 1;
 372         }
 373         buf[0] = tmp;
 374
 375         return baud;
 376 }
 377
 378 static void pl2303_encode_baud_rate(struct tty_struct *tty,
 379                                         struct usb_serial_port *port,
 380                                         u8 buf[4])
 381 {
 382         struct usb_serial *serial = port->serial;
 383         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 384         speed_t baud_sup;
 385         speed_t baud;
 386
 387         baud = tty_get_baud_rate(tty);
 388         dev_dbg(&port->dev, "baud requested = %u\n", baud);
 389         if (!baud)
 390                 return;
 391
 392         if (spriv->type->max_baud_rate)
 393                 baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
 394         /*
 395          * Set baud rate to nearest supported value.
 396          *
 397          * NOTE: Baud rate 500k can only be set using divisors.
 398          */
 399         baud_sup = pl2303_get_supported_baud_rate(baud);
 400
 401         if (baud == 500000)
 402                 baud = pl2303_encode_baud_rate_divisor(buf, baud);
 403         else
 404                 baud = pl2303_encode_baud_rate_direct(buf, baud_sup);
 405
 406         /* Save resulting baud rate */
 407         tty_encode_baud_rate(tty, baud, baud);
 408         dev_dbg(&port->dev, "baud set = %u\n", baud);
 409 }
 410
 411 static int pl2303_get_line_request(struct usb_serial_port *port,
 412                                                         unsigned char buf[7])
 413 {
 414         struct usb_device *udev = port->serial->dev;
 415         int ret;
 416
 417         ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 418                                 GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
 419                                 0, 0, buf, 7, 100);
 420         if (ret != 7) {
 421                 dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
 422
 423                 if (ret > 0)
 424                         ret = -EIO;
 425
 426                 return ret;
 427         }
 428
 429         dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
 430
 431         return 0;
 432 }
 433
 434 static int pl2303_set_line_request(struct usb_serial_port *port,
 435                                                         unsigned char buf[7])
 436 {
 437         struct usb_device *udev = port->serial->dev;
 438         int ret;
 439
 440         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 441                                 SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
 442                                 0, 0, buf, 7, 100);
 443         if (ret != 7) {
 444                 dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
 445
 446                 if (ret > 0)
 447                         ret = -EIO;
 448
 449                 return ret;
 450         }
 451
 452         dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
 453
 454         return 0;
 455 }
 456
 457 static void pl2303_set_termios(struct tty_struct *tty,
 458                 struct usb_serial_port *port, struct ktermios *old_termios)
 459 {
 460         struct usb_serial *serial = port->serial;
 461         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 462         struct pl2303_private *priv = usb_get_serial_port_data(port);
 463         unsigned long flags;
 464         unsigned char *buf;
 465         int ret;
 466         u8 control;
 467
 468         if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
 469                 return;
 470
 471         buf = kzalloc(7, GFP_KERNEL);
 472         if (!buf) {
 473                 /* Report back no change occurred */
 474                 if (old_termios)
 475                         tty->termios = *old_termios;
 476                 return;
 477         }
 478
 479         pl2303_get_line_request(port, buf);
 480
 481         switch (C_CSIZE(tty)) {
 482         case CS5:
 483                 buf[6] = 5;
 484                 break;
 485         case CS6:
 486                 buf[6] = 6;
 487                 break;
 488         case CS7:
 489                 buf[6] = 7;
 490                 break;
 491         default:
 492         case CS8:
 493                 buf[6] = 8;
 494         }
 495         dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
 496
 497         /* For reference buf[0]:buf[3] baud rate value */
 498         pl2303_encode_baud_rate(tty, port, &buf[0]);
 499
 500         /* For reference buf[4]=0 is 1 stop bits */
 501         /* For reference buf[4]=1 is 1.5 stop bits */
 502         /* For reference buf[4]=2 is 2 stop bits */
 503         if (C_CSTOPB(tty)) {
 504                 /*
 505                  * NOTE: Comply with "real" UARTs / RS232:
 506                  *       use 1.5 instead of 2 stop bits with 5 data bits
 507                  */
 508                 if (C_CSIZE(tty) == CS5) {
 509                         buf[4] = 1;
 510                         dev_dbg(&port->dev, "stop bits = 1.5\n");
 511                 } else {
 512                         buf[4] = 2;
 513                         dev_dbg(&port->dev, "stop bits = 2\n");
 514                 }
 515         } else {
 516                 buf[4] = 0;
 517                 dev_dbg(&port->dev, "stop bits = 1\n");
 518         }
 519
 520         if (C_PARENB(tty)) {
 521                 /* For reference buf[5]=0 is none parity */
 522                 /* For reference buf[5]=1 is odd parity */
 523                 /* For reference buf[5]=2 is even parity */
 524                 /* For reference buf[5]=3 is mark parity */
 525                 /* For reference buf[5]=4 is space parity */
 526                 if (C_PARODD(tty)) {
 527                         if (C_CMSPAR(tty)) {
 528                                 buf[5] = 3;
 529                                 dev_dbg(&port->dev, "parity = mark\n");
 530                         } else {
 531                                 buf[5] = 1;
 532                                 dev_dbg(&port->dev, "parity = odd\n");
 533                         }
 534                 } else {
 535                         if (C_CMSPAR(tty)) {
 536                                 buf[5] = 4;
 537                                 dev_dbg(&port->dev, "parity = space\n");
 538                         } else {
 539                                 buf[5] = 2;
 540                                 dev_dbg(&port->dev, "parity = even\n");
 541                         }
 542                 }
 543         } else {
 544                 buf[5] = 0;
 545                 dev_dbg(&port->dev, "parity = none\n");
 546         }
 547
 548         /*
 549          * Some PL2303 are known to lose bytes if you change serial settings
 550          * even to the same values as before. Thus we actually need to filter
 551          * in this specific case.
 552          *
 553          * Note that the tty_termios_hw_change check above is not sufficient
 554          * as a previously requested baud rate may differ from the one
 555          * actually used (and stored in old_termios).
 556          *
 557          * NOTE: No additional locking needed for line_settings as it is
 558          *       only used in set_termios, which is serialised against itself.
 559          */
 560         if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
 561                 ret = pl2303_set_line_request(port, buf);
 562                 if (!ret)
 563                         memcpy(priv->line_settings, buf, 7);
 564         }
 565
 566         /* change control lines if we are switching to or from B0 */
 567         spin_lock_irqsave(&priv->lock, flags);
 568         control = priv->line_control;
 569         if (C_BAUD(tty) == B0)
 570                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 571         else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
 572                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 573         if (control != priv->line_control) {
 574                 control = priv->line_control;
 575                 spin_unlock_irqrestore(&priv->lock, flags);
 576                 pl2303_set_control_lines(port, control);
 577         } else {
 578                 spin_unlock_irqrestore(&priv->lock, flags);
 579         }
 580
 581         if (C_CRTSCTS(tty)) {
 582                 if (spriv->quirks & PL2303_QUIRK_LEGACY)
 583                         pl2303_vendor_write(serial, 0x0, 0x41);
 584                 else
 585                         pl2303_vendor_write(serial, 0x0, 0x61);
 586         } else {
 587                 pl2303_vendor_write(serial, 0x0, 0x0);
 588         }
 589
 590         kfree(buf);
 591 }
 592
 593 static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
 594 {
 595         struct pl2303_private *priv = usb_get_serial_port_data(port);
 596         unsigned long flags;
 597         u8 control;
 598
 599         spin_lock_irqsave(&priv->lock, flags);
 600         if (on)
 601                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 602         else
 603                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 604         control = priv->line_control;
 605         spin_unlock_irqrestore(&priv->lock, flags);
 606
 607         pl2303_set_control_lines(port, control);
 608 }
 609
 610 static void pl2303_close(struct usb_serial_port *port)
 611 {
 612         usb_serial_generic_close(port);
 613         usb_kill_urb(port->interrupt_in_urb);
 614 }
 615
 616 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 617 {
 618         struct usb_serial *serial = port->serial;
 619         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 620         int result;
 621
 622         if (spriv->quirks & PL2303_QUIRK_LEGACY) {
 623                 usb_clear_halt(serial->dev, port->write_urb->pipe);
 624                 usb_clear_halt(serial->dev, port->read_urb->pipe);
 625         } else {
 626                 /* reset upstream data pipes */
 627                 pl2303_vendor_write(serial, 8, 0);
 628                 pl2303_vendor_write(serial, 9, 0);
 629         }
 630
 631         /* Setup termios */
 632         if (tty)
 633                 pl2303_set_termios(tty, port, NULL);
 634
 635         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 636         if (result) {
 637                 dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
 638                         result);
 639                 return result;
 640         }
 641
 642         result = usb_serial_generic_open(tty, port);
 643         if (result) {
 644                 usb_kill_urb(port->interrupt_in_urb);
 645                 return result;
 646         }
 647
 648         return 0;
 649 }
 650
 651 static int pl2303_tiocmset(struct tty_struct *tty,
 652                            unsigned int set, unsigned int clear)
 653 {
 654         struct usb_serial_port *port = tty->driver_data;
 655         struct pl2303_private *priv = usb_get_serial_port_data(port);
 656         unsigned long flags;
 657         u8 control;
 658         int ret;
 659
 660         spin_lock_irqsave(&priv->lock, flags);
 661         if (set & TIOCM_RTS)
 662                 priv->line_control |= CONTROL_RTS;
 663         if (set & TIOCM_DTR)
 664                 priv->line_control |= CONTROL_DTR;
 665         if (clear & TIOCM_RTS)
 666                 priv->line_control &= ~CONTROL_RTS;
 667         if (clear & TIOCM_DTR)
 668                 priv->line_control &= ~CONTROL_DTR;
 669         control = priv->line_control;
 670         spin_unlock_irqrestore(&priv->lock, flags);
 671
 672         ret = pl2303_set_control_lines(port, control);
 673         if (ret)
 674                 return usb_translate_errors(ret);
 675
 676         return 0;
 677 }
 678
 679 static int pl2303_tiocmget(struct tty_struct *tty)
 680 {
 681         struct usb_serial_port *port = tty->driver_data;
 682         struct pl2303_private *priv = usb_get_serial_port_data(port);
 683         unsigned long flags;
 684         unsigned int mcr;
 685         unsigned int status;
 686         unsigned int result;
 687
 688         spin_lock_irqsave(&priv->lock, flags);
 689         mcr = priv->line_control;
 690         status = priv->line_status;
 691         spin_unlock_irqrestore(&priv->lock, flags);
 692
 693         result = ((mcr & CONTROL_DTR)           ? TIOCM_DTR : 0)
 694                   | ((mcr & CONTROL_RTS)        ? TIOCM_RTS : 0)
 695                   | ((status & UART_CTS)        ? TIOCM_CTS : 0)
 696                   | ((status & UART_DSR)        ? TIOCM_DSR : 0)
 697                   | ((status & UART_RING)       ? TIOCM_RI  : 0)
 698                   | ((status & UART_DCD)        ? TIOCM_CD  : 0);
 699
 700         dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
 701
 702         return result;
 703 }
 704
 705 static int pl2303_carrier_raised(struct usb_serial_port *port)
 706 {
 707         struct pl2303_private *priv = usb_get_serial_port_data(port);
 708
 709         if (priv->line_status & UART_DCD)
 710                 return 1;
 711
 712         return 0;
 713 }
 714
 715 static int pl2303_ioctl(struct tty_struct *tty,
 716                         unsigned int cmd, unsigned long arg)
 717 {
 718         struct serial_struct ser;
 719         struct usb_serial_port *port = tty->driver_data;
 720
 721         switch (cmd) {
 722         case TIOCGSERIAL:
 723                 memset(&ser, 0, sizeof ser);
 724                 ser.type = PORT_16654;
 725                 ser.line = port->minor;
 726                 ser.port = port->port_number;
 727                 ser.baud_base = 460800;
 728
 729                 if (copy_to_user((void __user *)arg, &ser, sizeof ser))
 730                         return -EFAULT;
 731
 732                 return 0;
 733         default:
 734                 break;
 735         }
 736
 737         return -ENOIOCTLCMD;
 738 }
 739
 740 static void pl2303_break_ctl(struct tty_struct *tty, int break_state)
 741 {
 742         struct usb_serial_port *port = tty->driver_data;
 743         struct usb_serial *serial = port->serial;
 744         u16 state;
 745         int result;
 746
 747         if (break_state == 0)
 748                 state = BREAK_OFF;
 749         else
 750                 state = BREAK_ON;
 751
 752         dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
 753                         state == BREAK_OFF ? "off" : "on");
 754
 755         result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 756                                  BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
 757                                  0, NULL, 0, 100);
 758         if (result)
 759                 dev_err(&port->dev, "error sending break = %d\n", result);
 760 }
 761
 762 static void pl2303_update_line_status(struct usb_serial_port *port,
 763                                       unsigned char *data,
 764                                       unsigned int actual_length)
 765 {
 766         struct usb_serial *serial = port->serial;
 767         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 768         struct pl2303_private *priv = usb_get_serial_port_data(port);
 769         struct tty_struct *tty;
 770         unsigned long flags;
 771         unsigned int status_idx = UART_STATE_INDEX;
 772         u8 status;
 773         u8 delta;
 774
 775         if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
 776                 status_idx = 0;
 777
 778         if (actual_length < status_idx + 1)
 779                 return;
 780
 781         status = data[status_idx];
 782
 783         /* Save off the uart status for others to look at */
 784         spin_lock_irqsave(&priv->lock, flags);
 785         delta = priv->line_status ^ status;
 786         priv->line_status = status;
 787         spin_unlock_irqrestore(&priv->lock, flags);
 788
 789         if (status & UART_BREAK_ERROR)
 790                 usb_serial_handle_break(port);
 791
 792         if (delta & UART_STATE_MSR_MASK) {
 793                 if (delta & UART_CTS)
 794                         port->icount.cts++;
 795                 if (delta & UART_DSR)
 796                         port->icount.dsr++;
 797                 if (delta & UART_RING)
 798                         port->icount.rng++;
 799                 if (delta & UART_DCD) {
 800                         port->icount.dcd++;
 801                         tty = tty_port_tty_get(&port->port);
 802                         if (tty) {
 803                                 usb_serial_handle_dcd_change(port, tty,
 804                                                         status & UART_DCD);
 805                                 tty_kref_put(tty);
 806                         }
 807                 }
 808
 809                 wake_up_interruptible(&port->port.delta_msr_wait);
 810         }
 811 }
 812
 813 static void pl2303_read_int_callback(struct urb *urb)
 814 {
 815         struct usb_serial_port *port =  urb->context;
 816         unsigned char *data = urb->transfer_buffer;
 817         unsigned int actual_length = urb->actual_length;
 818         int status = urb->status;
 819         int retval;
 820
 821         switch (status) {
 822         case 0:
 823                 /* success */
 824                 break;
 825         case -ECONNRESET:
 826         case -ENOENT:
 827         case -ESHUTDOWN:
 828                 /* this urb is terminated, clean up */
 829                 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
 830                         __func__, status);
 831                 return;
 832         default:
 833                 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
 834                         __func__, status);
 835                 goto exit;
 836         }
 837
 838         usb_serial_debug_data(&port->dev, __func__,
 839                               urb->actual_length, urb->transfer_buffer);
 840
 841         pl2303_update_line_status(port, data, actual_length);
 842
 843 exit:
 844         retval = usb_submit_urb(urb, GFP_ATOMIC);
 845         if (retval) {
 846                 dev_err(&port->dev,
 847                         "%s - usb_submit_urb failed with result %d\n",
 848                         __func__, retval);
 849         }
 850 }
 851
 852 static void pl2303_process_read_urb(struct urb *urb)
 853 {
 854         struct usb_serial_port *port = urb->context;
 855         struct pl2303_private *priv = usb_get_serial_port_data(port);
 856         unsigned char *data = urb->transfer_buffer;
 857         char tty_flag = TTY_NORMAL;
 858         unsigned long flags;
 859         u8 line_status;
 860         int i;
 861
 862         /* update line status */
 863         spin_lock_irqsave(&priv->lock, flags);
 864         line_status = priv->line_status;
 865         priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
 866         spin_unlock_irqrestore(&priv->lock, flags);
 867
 868         if (!urb->actual_length)
 869                 return;
 870
 871         /*
 872          * Break takes precedence over parity, which takes precedence over
 873          * framing errors.
 874          */
 875         if (line_status & UART_BREAK_ERROR)
 876                 tty_flag = TTY_BREAK;
 877         else if (line_status & UART_PARITY_ERROR)
 878                 tty_flag = TTY_PARITY;
 879         else if (line_status & UART_FRAME_ERROR)
 880                 tty_flag = TTY_FRAME;
 881
 882         if (tty_flag != TTY_NORMAL)
 883                 dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
 884                                                                 tty_flag);
 885         /* overrun is special, not associated with a char */
 886         if (line_status & UART_OVERRUN_ERROR)
 887                 tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
 888
 889         if (port->port.console && port->sysrq) {
 890                 for (i = 0; i < urb->actual_length; ++i)
 891                         if (!usb_serial_handle_sysrq_char(port, data[i]))
 892                                 tty_insert_flip_char(&port->port, data[i],
 893                                                 tty_flag);
 894         } else {
 895                 tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
 896                                                         urb->actual_length);
 897         }
 898
 899         tty_flip_buffer_push(&port->port);
 900 }
 901
 902 static struct usb_serial_driver pl2303_device = {
 903         .driver = {
 904                 .owner =        THIS_MODULE,
 905                 .name =         "pl2303",
 906         },
 907         .id_table =             id_table,
 908         .num_ports =            1,
 909         .bulk_in_size =         256,
 910         .bulk_out_size =        256,
 911         .open =                 pl2303_open,
 912         .close =                pl2303_close,
 913         .dtr_rts =              pl2303_dtr_rts,
 914         .carrier_raised =       pl2303_carrier_raised,
 915         .ioctl =                pl2303_ioctl,
 916         .break_ctl =            pl2303_break_ctl,
 917         .set_termios =          pl2303_set_termios,
 918         .tiocmget =             pl2303_tiocmget,
 919         .tiocmset =             pl2303_tiocmset,
 920         .tiocmiwait =           usb_serial_generic_tiocmiwait,
 921         .process_read_urb =     pl2303_process_read_urb,
 922         .read_int_callback =    pl2303_read_int_callback,
 923         .probe =                pl2303_probe,
 924         .attach =               pl2303_startup,
 925         .release =              pl2303_release,
 926         .port_probe =           pl2303_port_probe,
 927         .port_remove =          pl2303_port_remove,
 928 };
 929
 930 static struct usb_serial_driver * const serial_drivers[] = {
 931         &pl2303_device, NULL
 932 };
 933
 934 module_usb_serial_driver(serial_drivers, id_table);
 935
 936 MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
 937 MODULE_LICENSE("GPL");