drivers/usb/serial/pl2303.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Prolific PL2303 USB to serial adaptor driver
   4  *
   5  * Copyright (C) 2001-2007 Greg Kroah-Hartman (greg@kroah.com)
   6  * Copyright (C) 2003 IBM Corp.
   7  *
   8  * Original driver for 2.2.x by anonymous
   9  *
  10  * See Documentation/usb/usb-serial.rst for more information on using this
  11  * driver
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/errno.h>
  16 #include <linux/slab.h>
  17 #include <linux/tty.h>
  18 #include <linux/tty_driver.h>
  19 #include <linux/tty_flip.h>
  20 #include <linux/serial.h>
  21 #include <linux/module.h>
  22 #include <linux/moduleparam.h>
  23 #include <linux/spinlock.h>
  24 #include <linux/uaccess.h>
  25 #include <linux/usb.h>
  26 #include <linux/usb/serial.h>
  27 #include <asm/unaligned.h>
  28 #include "pl2303.h"
  29
  30
  31 #define PL2303_QUIRK_UART_STATE_IDX0            BIT(0)
  32 #define PL2303_QUIRK_LEGACY                     BIT(1)
  33 #define PL2303_QUIRK_ENDPOINT_HACK              BIT(2)
  34
  35 static const struct usb_device_id id_table[] = {
  36         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID),
  37                 .driver_info = PL2303_QUIRK_ENDPOINT_HACK },
  38         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
  39         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
  40         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
  41         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_CHILITAG) },
  42         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_PHAROS) },
  43         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ALDIGA) },
  44         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MMX) },
  45         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GPRS) },
  46         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_HCR331) },
  47         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MOTOROLA) },
  48         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ZTEK) },
  49         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_TB) },
  50         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GC) },
  51         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GB) },
  52         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GT) },
  53         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GL) },
  54         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GE) },
  55         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GS) },
  56         { USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
  57         { USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID_RSAQ5) },
  58         { USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID),
  59                 .driver_info = PL2303_QUIRK_ENDPOINT_HACK },
  60         { USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_UC485),
  61                 .driver_info = PL2303_QUIRK_ENDPOINT_HACK },
  62         { USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_UC232B),
  63                 .driver_info = PL2303_QUIRK_ENDPOINT_HACK },
  64         { USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID2) },
  65         { USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
  66         { USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
  67         { USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
  68         { USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
  69         { USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
  70         { USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
  71         { USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
  72         { USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
  73         { USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
  74         { USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
  75         { USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
  76         { USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
  77         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1),
  78                 .driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
  79         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65),
  80                 .driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
  81         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75),
  82                 .driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
  83         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81),
  84                 .driver_info = PL2303_QUIRK_ENDPOINT_HACK },
  85         { USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
  86         { USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
  87         { USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
  88         { USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
  89         { USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
  90         { USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
  91         { USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
  92         { USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
  93         { USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
  94         { USB_DEVICE(ALCOR_VENDOR_ID, ALCOR_PRODUCT_ID),
  95                 .driver_info = PL2303_QUIRK_ENDPOINT_HACK },
  96         { USB_DEVICE(WS002IN_VENDOR_ID, WS002IN_PRODUCT_ID) },
  97         { USB_DEVICE(COREGA_VENDOR_ID, COREGA_PRODUCT_ID) },
  98         { USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
  99         { USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
 100         { USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
 101         { USB_DEVICE(HP_VENDOR_ID, HP_LD220TA_PRODUCT_ID) },
 102         { USB_DEVICE(HP_VENDOR_ID, HP_LD381_PRODUCT_ID) },
 103         { USB_DEVICE(HP_VENDOR_ID, HP_LD381GC_PRODUCT_ID) },
 104         { USB_DEVICE(HP_VENDOR_ID, HP_LD960_PRODUCT_ID) },
 105         { USB_DEVICE(HP_VENDOR_ID, HP_LD960TA_PRODUCT_ID) },
 106         { USB_DEVICE(HP_VENDOR_ID, HP_LCM220_PRODUCT_ID) },
 107         { USB_DEVICE(HP_VENDOR_ID, HP_LCM960_PRODUCT_ID) },
 108         { USB_DEVICE(HP_VENDOR_ID, HP_LM920_PRODUCT_ID) },
 109         { USB_DEVICE(HP_VENDOR_ID, HP_LM940_PRODUCT_ID) },
 110         { USB_DEVICE(HP_VENDOR_ID, HP_TD620_PRODUCT_ID) },
 111         { USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
 112         { USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
 113         { USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
 114         { USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
 115         { USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
 116         { USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530GC_PRODUCT_ID) },
 117         { USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
 118         { USB_DEVICE(AT_VENDOR_ID, AT_VTKIT3_PRODUCT_ID) },
 119         { }                                     /* Terminating entry */
 120 };
 121
 122 MODULE_DEVICE_TABLE(usb, id_table);
 123
 124 #define SET_LINE_REQUEST_TYPE           0x21
 125 #define SET_LINE_REQUEST                0x20
 126
 127 #define SET_CONTROL_REQUEST_TYPE        0x21
 128 #define SET_CONTROL_REQUEST             0x22
 129 #define CONTROL_DTR                     0x01
 130 #define CONTROL_RTS                     0x02
 131
 132 #define BREAK_REQUEST_TYPE              0x21
 133 #define BREAK_REQUEST                   0x23
 134 #define BREAK_ON                        0xffff
 135 #define BREAK_OFF                       0x0000
 136
 137 #define GET_LINE_REQUEST_TYPE           0xa1
 138 #define GET_LINE_REQUEST                0x21
 139
 140 #define VENDOR_WRITE_REQUEST_TYPE       0x40
 141 #define VENDOR_WRITE_REQUEST            0x01
 142 #define VENDOR_WRITE_NREQUEST           0x80
 143
 144 #define VENDOR_READ_REQUEST_TYPE        0xc0
 145 #define VENDOR_READ_REQUEST             0x01
 146 #define VENDOR_READ_NREQUEST            0x81
 147
 148 #define UART_STATE_INDEX                8
 149 #define UART_STATE_MSR_MASK             0x8b
 150 #define UART_STATE_TRANSIENT_MASK       0x74
 151 #define UART_DCD                        0x01
 152 #define UART_DSR                        0x02
 153 #define UART_BREAK_ERROR                0x04
 154 #define UART_RING                       0x08
 155 #define UART_FRAME_ERROR                0x10
 156 #define UART_PARITY_ERROR               0x20
 157 #define UART_OVERRUN_ERROR              0x40
 158 #define UART_CTS                        0x80
 159
 160 #define PL2303_FLOWCTRL_MASK            0xf0
 161
 162 #define PL2303_READ_TYPE_HX_STATUS      0x8080
 163
 164 #define PL2303_HXN_RESET_REG            0x07
 165 #define PL2303_HXN_RESET_UPSTREAM_PIPE  0x02
 166 #define PL2303_HXN_RESET_DOWNSTREAM_PIPE        0x01
 167
 168 #define PL2303_HXN_FLOWCTRL_REG         0x0a
 169 #define PL2303_HXN_FLOWCTRL_MASK        0x1c
 170 #define PL2303_HXN_FLOWCTRL_NONE        0x1c
 171 #define PL2303_HXN_FLOWCTRL_RTS_CTS     0x18
 172 #define PL2303_HXN_FLOWCTRL_XON_XOFF    0x0c
 173
 174 static void pl2303_set_break(struct usb_serial_port *port, bool enable);
 175
 176 enum pl2303_type {
 177         TYPE_H,
 178         TYPE_HX,
 179         TYPE_TA,
 180         TYPE_TB,
 181         TYPE_HXD,
 182         TYPE_HXN,
 183         TYPE_COUNT
 184 };
 185
 186 struct pl2303_type_data {
 187         const char *name;
 188         speed_t max_baud_rate;
 189         unsigned long quirks;
 190         unsigned int no_autoxonxoff:1;
 191         unsigned int no_divisors:1;
 192         unsigned int alt_divisors:1;
 193 };
 194
 195 struct pl2303_serial_private {
 196         const struct pl2303_type_data *type;
 197         unsigned long quirks;
 198 };
 199
 200 struct pl2303_private {
 201         spinlock_t lock;
 202         u8 line_control;
 203         u8 line_status;
 204
 205         u8 line_settings[7];
 206 };
 207
 208 static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
 209         [TYPE_H] = {
 210                 .name                   = "H",
 211                 .max_baud_rate          = 1228800,
 212                 .quirks                 = PL2303_QUIRK_LEGACY,
 213                 .no_autoxonxoff         = true,
 214         },
 215         [TYPE_HX] = {
 216                 .name                   = "HX",
 217                 .max_baud_rate          = 6000000,
 218         },
 219         [TYPE_TA] = {
 220                 .name                   = "TA",
 221                 .max_baud_rate          = 6000000,
 222                 .alt_divisors           = true,
 223         },
 224         [TYPE_TB] = {
 225                 .name                   = "TB",
 226                 .max_baud_rate          = 12000000,
 227                 .alt_divisors           = true,
 228         },
 229         [TYPE_HXD] = {
 230                 .name                   = "HXD",
 231                 .max_baud_rate          = 12000000,
 232         },
 233         [TYPE_HXN] = {
 234                 .name                   = "G",
 235                 .max_baud_rate          = 12000000,
 236                 .no_divisors            = true,
 237         },
 238 };
 239
 240 static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
 241                                                         unsigned char buf[1])
 242 {
 243         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 244         struct device *dev = &serial->interface->dev;
 245         u8 request;
 246         int res;
 247
 248         if (spriv->type == &pl2303_type_data[TYPE_HXN])
 249                 request = VENDOR_READ_NREQUEST;
 250         else
 251                 request = VENDOR_READ_REQUEST;
 252
 253         res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 254                         request, VENDOR_READ_REQUEST_TYPE,
 255                         value, 0, buf, 1, 100);
 256         if (res != 1) {
 257                 dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
 258                                                                 value, res);
 259                 if (res >= 0)
 260                         res = -EIO;
 261
 262                 return res;
 263         }
 264
 265         dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
 266
 267         return 0;
 268 }
 269
 270 static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
 271 {
 272         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 273         struct device *dev = &serial->interface->dev;
 274         u8 request;
 275         int res;
 276
 277         dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
 278
 279         if (spriv->type == &pl2303_type_data[TYPE_HXN])
 280                 request = VENDOR_WRITE_NREQUEST;
 281         else
 282                 request = VENDOR_WRITE_REQUEST;
 283
 284         res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 285                         request, VENDOR_WRITE_REQUEST_TYPE,
 286                         value, index, NULL, 0, 100);
 287         if (res) {
 288                 dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
 289                                                                 value, res);
 290                 return res;
 291         }
 292
 293         return 0;
 294 }
 295
 296 static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val)
 297 {
 298         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 299         int ret = 0;
 300         u8 *buf;
 301
 302         buf = kmalloc(1, GFP_KERNEL);
 303         if (!buf)
 304                 return -ENOMEM;
 305
 306         if (spriv->type == &pl2303_type_data[TYPE_HXN])
 307                 ret = pl2303_vendor_read(serial, reg, buf);
 308         else
 309                 ret = pl2303_vendor_read(serial, reg | 0x80, buf);
 310
 311         if (ret)
 312                 goto out_free;
 313
 314         *buf &= ~mask;
 315         *buf |= val & mask;
 316
 317         ret = pl2303_vendor_write(serial, reg, *buf);
 318 out_free:
 319         kfree(buf);
 320
 321         return ret;
 322 }
 323
 324 static int pl2303_probe(struct usb_serial *serial,
 325                                         const struct usb_device_id *id)
 326 {
 327         usb_set_serial_data(serial, (void *)id->driver_info);
 328
 329         return 0;
 330 }
 331
 332 /*
 333  * Use interrupt endpoint from first interface if available.
 334  *
 335  * This is needed due to the looney way its endpoints are set up.
 336  */
 337 static int pl2303_endpoint_hack(struct usb_serial *serial,
 338                                         struct usb_serial_endpoints *epds)
 339 {
 340         struct usb_interface *interface = serial->interface;
 341         struct usb_device *dev = serial->dev;
 342         struct device *ddev = &interface->dev;
 343         struct usb_host_interface *iface_desc;
 344         struct usb_endpoint_descriptor *endpoint;
 345         unsigned int i;
 346
 347         if (interface == dev->actconfig->interface[0])
 348                 return 0;
 349
 350         /* check out the endpoints of the other interface */
 351         iface_desc = dev->actconfig->interface[0]->cur_altsetting;
 352
 353         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 354                 endpoint = &iface_desc->endpoint[i].desc;
 355
 356                 if (!usb_endpoint_is_int_in(endpoint))
 357                         continue;
 358
 359                 dev_dbg(ddev, "found interrupt in on separate interface\n");
 360                 if (epds->num_interrupt_in < ARRAY_SIZE(epds->interrupt_in))
 361                         epds->interrupt_in[epds->num_interrupt_in++] = endpoint;
 362         }
 363
 364         return 0;
 365 }
 366
 367 static int pl2303_calc_num_ports(struct usb_serial *serial,
 368                                         struct usb_serial_endpoints *epds)
 369 {
 370         unsigned long quirks = (unsigned long)usb_get_serial_data(serial);
 371         struct device *dev = &serial->interface->dev;
 372         int ret;
 373
 374         if (quirks & PL2303_QUIRK_ENDPOINT_HACK) {
 375                 ret = pl2303_endpoint_hack(serial, epds);
 376                 if (ret)
 377                         return ret;
 378         }
 379
 380         if (epds->num_interrupt_in < 1) {
 381                 dev_err(dev, "required interrupt-in endpoint missing\n");
 382                 return -ENODEV;
 383         }
 384
 385         return 1;
 386 }
 387
 388 static bool pl2303_supports_hx_status(struct usb_serial *serial)
 389 {
 390         int ret;
 391         u8 buf;
 392
 393         ret = usb_control_msg_recv(serial->dev, 0, VENDOR_READ_REQUEST,
 394                         VENDOR_READ_REQUEST_TYPE, PL2303_READ_TYPE_HX_STATUS,
 395                         0, &buf, 1, 100, GFP_KERNEL);
 396
 397         return ret == 0;
 398 }
 399
 400 static int pl2303_detect_type(struct usb_serial *serial)
 401 {
 402         struct usb_device_descriptor *desc = &serial->dev->descriptor;
 403         u16 bcdDevice, bcdUSB;
 404
 405         /*
 406          * Legacy PL2303H, variants 0 and 1 (difference unknown).
 407          */
 408         if (desc->bDeviceClass == 0x02)
 409                 return TYPE_H;          /* variant 0 */
 410
 411         if (desc->bMaxPacketSize0 != 0x40) {
 412                 if (desc->bDeviceClass == 0x00 || desc->bDeviceClass == 0xff)
 413                         return TYPE_H;  /* variant 1 */
 414
 415                 return TYPE_H;          /* variant 0 */
 416         }
 417
 418         bcdDevice = le16_to_cpu(desc->bcdDevice);
 419         bcdUSB = le16_to_cpu(desc->bcdUSB);
 420
 421         switch (bcdUSB) {
 422         case 0x110:
 423                 switch (bcdDevice) {
 424                 case 0x300:
 425                         return TYPE_HX;
 426                 case 0x400:
 427                         return TYPE_HXD;
 428                 default:
 429                         return TYPE_HX;
 430                 }
 431                 break;
 432         case 0x200:
 433                 switch (bcdDevice) {
 434                 case 0x100:
 435                 case 0x305:
 436                 case 0x405:
 437                         /*
 438                          * Assume it's an HXN-type if the device doesn't
 439                          * support the old read request value.
 440                          */
 441                         if (!pl2303_supports_hx_status(serial))
 442                                 return TYPE_HXN;
 443                         break;
 444                 case 0x300:
 445                         return TYPE_TA;
 446                 case 0x500:
 447                         return TYPE_TB;
 448                 }
 449                 break;
 450         }
 451
 452         dev_err(&serial->interface->dev,
 453                         "unknown device type, please report to linux-usb@vger.kernel.org\n");
 454         return -ENODEV;
 455 }
 456
 457 static int pl2303_startup(struct usb_serial *serial)
 458 {
 459         struct pl2303_serial_private *spriv;
 460         enum pl2303_type type;
 461         unsigned char *buf;
 462         int ret;
 463
 464         ret = pl2303_detect_type(serial);
 465         if (ret < 0)
 466                 return ret;
 467
 468         type = ret;
 469         dev_dbg(&serial->interface->dev, "device type: %s\n", pl2303_type_data[type].name);
 470
 471         spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
 472         if (!spriv)
 473                 return -ENOMEM;
 474
 475         spriv->type = &pl2303_type_data[type];
 476         spriv->quirks = (unsigned long)usb_get_serial_data(serial);
 477         spriv->quirks |= spriv->type->quirks;
 478
 479         usb_set_serial_data(serial, spriv);
 480
 481         if (type != TYPE_HXN) {
 482                 buf = kmalloc(1, GFP_KERNEL);
 483                 if (!buf) {
 484                         kfree(spriv);
 485                         return -ENOMEM;
 486                 }
 487
 488                 pl2303_vendor_read(serial, 0x8484, buf);
 489                 pl2303_vendor_write(serial, 0x0404, 0);
 490                 pl2303_vendor_read(serial, 0x8484, buf);
 491                 pl2303_vendor_read(serial, 0x8383, buf);
 492                 pl2303_vendor_read(serial, 0x8484, buf);
 493                 pl2303_vendor_write(serial, 0x0404, 1);
 494                 pl2303_vendor_read(serial, 0x8484, buf);
 495                 pl2303_vendor_read(serial, 0x8383, buf);
 496                 pl2303_vendor_write(serial, 0, 1);
 497                 pl2303_vendor_write(serial, 1, 0);
 498                 if (spriv->quirks & PL2303_QUIRK_LEGACY)
 499                         pl2303_vendor_write(serial, 2, 0x24);
 500                 else
 501                         pl2303_vendor_write(serial, 2, 0x44);
 502
 503                 kfree(buf);
 504         }
 505
 506         return 0;
 507 }
 508
 509 static void pl2303_release(struct usb_serial *serial)
 510 {
 511         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 512
 513         kfree(spriv);
 514 }
 515
 516 static int pl2303_port_probe(struct usb_serial_port *port)
 517 {
 518         struct pl2303_private *priv;
 519
 520         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 521         if (!priv)
 522                 return -ENOMEM;
 523
 524         spin_lock_init(&priv->lock);
 525
 526         usb_set_serial_port_data(port, priv);
 527
 528         port->port.drain_delay = 256;
 529
 530         return 0;
 531 }
 532
 533 static void pl2303_port_remove(struct usb_serial_port *port)
 534 {
 535         struct pl2303_private *priv = usb_get_serial_port_data(port);
 536
 537         kfree(priv);
 538 }
 539
 540 static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
 541 {
 542         struct usb_device *dev = port->serial->dev;
 543         int retval;
 544
 545         dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
 546
 547         retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 548                                  SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
 549                                  value, 0, NULL, 0, 100);
 550         if (retval)
 551                 dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
 552
 553         return retval;
 554 }
 555
 556 /*
 557  * Returns the nearest supported baud rate that can be set directly without
 558  * using divisors.
 559  */
 560 static speed_t pl2303_get_supported_baud_rate(speed_t baud)
 561 {
 562         static const speed_t baud_sup[] = {
 563                 75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
 564                 14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
 565                 614400, 921600, 1228800, 2457600, 3000000, 6000000
 566         };
 567
 568         unsigned i;
 569
 570         for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
 571                 if (baud_sup[i] > baud)
 572                         break;
 573         }
 574
 575         if (i == ARRAY_SIZE(baud_sup))
 576                 baud = baud_sup[i - 1];
 577         else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
 578                 baud = baud_sup[i - 1];
 579         else
 580                 baud = baud_sup[i];
 581
 582         return baud;
 583 }
 584
 585 /*
 586  * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
 587  *       use 9600 baud.
 588  */
 589 static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
 590                                                                 speed_t baud)
 591 {
 592         put_unaligned_le32(baud, buf);
 593
 594         return baud;
 595 }
 596
 597 static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
 598                                                                 speed_t baud)
 599 {
 600         unsigned int baseline, mantissa, exponent;
 601
 602         /*
 603          * Apparently the formula is:
 604          *   baudrate = 12M * 32 / (mantissa * 4^exponent)
 605          * where
 606          *   mantissa = buf[8:0]
 607          *   exponent = buf[11:9]
 608          */
 609         baseline = 12000000 * 32;
 610         mantissa = baseline / baud;
 611         if (mantissa == 0)
 612                 mantissa = 1;   /* Avoid dividing by zero if baud > 32*12M. */
 613         exponent = 0;
 614         while (mantissa >= 512) {
 615                 if (exponent < 7) {
 616                         mantissa >>= 2; /* divide by 4 */
 617                         exponent++;
 618                 } else {
 619                         /* Exponent is maxed. Trim mantissa and leave. */
 620                         mantissa = 511;
 621                         break;
 622                 }
 623         }
 624
 625         buf[3] = 0x80;
 626         buf[2] = 0;
 627         buf[1] = exponent << 1 | mantissa >> 8;
 628         buf[0] = mantissa & 0xff;
 629
 630         /* Calculate and return the exact baud rate. */
 631         baud = (baseline / mantissa) >> (exponent << 1);
 632
 633         return baud;
 634 }
 635
 636 static speed_t pl2303_encode_baud_rate_divisor_alt(unsigned char buf[4],
 637                                                                 speed_t baud)
 638 {
 639         unsigned int baseline, mantissa, exponent;
 640
 641         /*
 642          * Apparently, for the TA version the formula is:
 643          *   baudrate = 12M * 32 / (mantissa * 2^exponent)
 644          * where
 645          *   mantissa = buf[10:0]
 646          *   exponent = buf[15:13 16]
 647          */
 648         baseline = 12000000 * 32;
 649         mantissa = baseline / baud;
 650         if (mantissa == 0)
 651                 mantissa = 1;   /* Avoid dividing by zero if baud > 32*12M. */
 652         exponent = 0;
 653         while (mantissa >= 2048) {
 654                 if (exponent < 15) {
 655                         mantissa >>= 1; /* divide by 2 */
 656                         exponent++;
 657                 } else {
 658                         /* Exponent is maxed. Trim mantissa and leave. */
 659                         mantissa = 2047;
 660                         break;
 661                 }
 662         }
 663
 664         buf[3] = 0x80;
 665         buf[2] = exponent & 0x01;
 666         buf[1] = (exponent & ~0x01) << 4 | mantissa >> 8;
 667         buf[0] = mantissa & 0xff;
 668
 669         /* Calculate and return the exact baud rate. */
 670         baud = (baseline / mantissa) >> exponent;
 671
 672         return baud;
 673 }
 674
 675 static void pl2303_encode_baud_rate(struct tty_struct *tty,
 676                                         struct usb_serial_port *port,
 677                                         u8 buf[4])
 678 {
 679         struct usb_serial *serial = port->serial;
 680         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 681         speed_t baud_sup;
 682         speed_t baud;
 683
 684         baud = tty_get_baud_rate(tty);
 685         dev_dbg(&port->dev, "baud requested = %u\n", baud);
 686         if (!baud)
 687                 return;
 688
 689         if (spriv->type->max_baud_rate)
 690                 baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
 691         /*
 692          * Use direct method for supported baud rates, otherwise use divisors.
 693          * Newer chip types do not support divisor encoding.
 694          */
 695         if (spriv->type->no_divisors)
 696                 baud_sup = baud;
 697         else
 698                 baud_sup = pl2303_get_supported_baud_rate(baud);
 699
 700         if (baud == baud_sup)
 701                 baud = pl2303_encode_baud_rate_direct(buf, baud);
 702         else if (spriv->type->alt_divisors)
 703                 baud = pl2303_encode_baud_rate_divisor_alt(buf, baud);
 704         else
 705                 baud = pl2303_encode_baud_rate_divisor(buf, baud);
 706
 707         /* Save resulting baud rate */
 708         tty_encode_baud_rate(tty, baud, baud);
 709         dev_dbg(&port->dev, "baud set = %u\n", baud);
 710 }
 711
 712 static int pl2303_get_line_request(struct usb_serial_port *port,
 713                                                         unsigned char buf[7])
 714 {
 715         struct usb_device *udev = port->serial->dev;
 716         int ret;
 717
 718         ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 719                                 GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
 720                                 0, 0, buf, 7, 100);
 721         if (ret != 7) {
 722                 dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
 723
 724                 if (ret >= 0)
 725                         ret = -EIO;
 726
 727                 return ret;
 728         }
 729
 730         dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
 731
 732         return 0;
 733 }
 734
 735 static int pl2303_set_line_request(struct usb_serial_port *port,
 736                                                         unsigned char buf[7])
 737 {
 738         struct usb_device *udev = port->serial->dev;
 739         int ret;
 740
 741         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 742                                 SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
 743                                 0, 0, buf, 7, 100);
 744         if (ret < 0) {
 745                 dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
 746                 return ret;
 747         }
 748
 749         dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
 750
 751         return 0;
 752 }
 753
 754 static bool pl2303_termios_change(const struct ktermios *a, const struct ktermios *b)
 755 {
 756         bool ixon_change;
 757
 758         ixon_change = ((a->c_iflag ^ b->c_iflag) & (IXON | IXANY)) ||
 759                         a->c_cc[VSTART] != b->c_cc[VSTART] ||
 760                         a->c_cc[VSTOP] != b->c_cc[VSTOP];
 761
 762         return tty_termios_hw_change(a, b) || ixon_change;
 763 }
 764
 765 static bool pl2303_enable_xonxoff(struct tty_struct *tty, const struct pl2303_type_data *type)
 766 {
 767         if (!I_IXON(tty) || I_IXANY(tty))
 768                 return false;
 769
 770         if (START_CHAR(tty) != 0x11 || STOP_CHAR(tty) != 0x13)
 771                 return false;
 772
 773         if (type->no_autoxonxoff)
 774                 return false;
 775
 776         return true;
 777 }
 778
 779 static void pl2303_set_termios(struct tty_struct *tty,
 780                 struct usb_serial_port *port, struct ktermios *old_termios)
 781 {
 782         struct usb_serial *serial = port->serial;
 783         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 784         struct pl2303_private *priv = usb_get_serial_port_data(port);
 785         unsigned long flags;
 786         unsigned char *buf;
 787         int ret;
 788         u8 control;
 789
 790         if (old_termios && !pl2303_termios_change(&tty->termios, old_termios))
 791                 return;
 792
 793         buf = kzalloc(7, GFP_KERNEL);
 794         if (!buf) {
 795                 /* Report back no change occurred */
 796                 if (old_termios)
 797                         tty->termios = *old_termios;
 798                 return;
 799         }
 800
 801         pl2303_get_line_request(port, buf);
 802
 803         buf[6] = tty_get_char_size(tty->termios.c_cflag);
 804         dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
 805
 806         /* For reference buf[0]:buf[3] baud rate value */
 807         pl2303_encode_baud_rate(tty, port, &buf[0]);
 808
 809         /* For reference buf[4]=0 is 1 stop bits */
 810         /* For reference buf[4]=1 is 1.5 stop bits */
 811         /* For reference buf[4]=2 is 2 stop bits */
 812         if (C_CSTOPB(tty)) {
 813                 /*
 814                  * NOTE: Comply with "real" UARTs / RS232:
 815                  *       use 1.5 instead of 2 stop bits with 5 data bits
 816                  */
 817                 if (C_CSIZE(tty) == CS5) {
 818                         buf[4] = 1;
 819                         dev_dbg(&port->dev, "stop bits = 1.5\n");
 820                 } else {
 821                         buf[4] = 2;
 822                         dev_dbg(&port->dev, "stop bits = 2\n");
 823                 }
 824         } else {
 825                 buf[4] = 0;
 826                 dev_dbg(&port->dev, "stop bits = 1\n");
 827         }
 828
 829         if (C_PARENB(tty)) {
 830                 /* For reference buf[5]=0 is none parity */
 831                 /* For reference buf[5]=1 is odd parity */
 832                 /* For reference buf[5]=2 is even parity */
 833                 /* For reference buf[5]=3 is mark parity */
 834                 /* For reference buf[5]=4 is space parity */
 835                 if (C_PARODD(tty)) {
 836                         if (C_CMSPAR(tty)) {
 837                                 buf[5] = 3;
 838                                 dev_dbg(&port->dev, "parity = mark\n");
 839                         } else {
 840                                 buf[5] = 1;
 841                                 dev_dbg(&port->dev, "parity = odd\n");
 842                         }
 843                 } else {
 844                         if (C_CMSPAR(tty)) {
 845                                 buf[5] = 4;
 846                                 dev_dbg(&port->dev, "parity = space\n");
 847                         } else {
 848                                 buf[5] = 2;
 849                                 dev_dbg(&port->dev, "parity = even\n");
 850                         }
 851                 }
 852         } else {
 853                 buf[5] = 0;
 854                 dev_dbg(&port->dev, "parity = none\n");
 855         }
 856
 857         /*
 858          * Some PL2303 are known to lose bytes if you change serial settings
 859          * even to the same values as before. Thus we actually need to filter
 860          * in this specific case.
 861          *
 862          * Note that the tty_termios_hw_change check above is not sufficient
 863          * as a previously requested baud rate may differ from the one
 864          * actually used (and stored in old_termios).
 865          *
 866          * NOTE: No additional locking needed for line_settings as it is
 867          *       only used in set_termios, which is serialised against itself.
 868          */
 869         if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
 870                 ret = pl2303_set_line_request(port, buf);
 871                 if (!ret)
 872                         memcpy(priv->line_settings, buf, 7);
 873         }
 874
 875         /* change control lines if we are switching to or from B0 */
 876         spin_lock_irqsave(&priv->lock, flags);
 877         control = priv->line_control;
 878         if (C_BAUD(tty) == B0)
 879                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 880         else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
 881                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 882         if (control != priv->line_control) {
 883                 control = priv->line_control;
 884                 spin_unlock_irqrestore(&priv->lock, flags);
 885                 pl2303_set_control_lines(port, control);
 886         } else {
 887                 spin_unlock_irqrestore(&priv->lock, flags);
 888         }
 889
 890         if (C_CRTSCTS(tty)) {
 891                 if (spriv->quirks & PL2303_QUIRK_LEGACY) {
 892                         pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40);
 893                 } else if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
 894                         pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
 895                                         PL2303_HXN_FLOWCTRL_MASK,
 896                                         PL2303_HXN_FLOWCTRL_RTS_CTS);
 897                 } else {
 898                         pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x60);
 899                 }
 900         } else if (pl2303_enable_xonxoff(tty, spriv->type)) {
 901                 if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
 902                         pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
 903                                         PL2303_HXN_FLOWCTRL_MASK,
 904                                         PL2303_HXN_FLOWCTRL_XON_XOFF);
 905                 } else {
 906                         pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0);
 907                 }
 908         } else {
 909                 if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
 910                         pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
 911                                         PL2303_HXN_FLOWCTRL_MASK,
 912                                         PL2303_HXN_FLOWCTRL_NONE);
 913                 } else {
 914                         pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
 915                 }
 916         }
 917
 918         kfree(buf);
 919 }
 920
 921 static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
 922 {
 923         struct pl2303_private *priv = usb_get_serial_port_data(port);
 924         unsigned long flags;
 925         u8 control;
 926
 927         spin_lock_irqsave(&priv->lock, flags);
 928         if (on)
 929                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 930         else
 931                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 932         control = priv->line_control;
 933         spin_unlock_irqrestore(&priv->lock, flags);
 934
 935         pl2303_set_control_lines(port, control);
 936 }
 937
 938 static void pl2303_close(struct usb_serial_port *port)
 939 {
 940         usb_serial_generic_close(port);
 941         usb_kill_urb(port->interrupt_in_urb);
 942         pl2303_set_break(port, false);
 943 }
 944
 945 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 946 {
 947         struct usb_serial *serial = port->serial;
 948         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 949         int result;
 950
 951         if (spriv->quirks & PL2303_QUIRK_LEGACY) {
 952                 usb_clear_halt(serial->dev, port->write_urb->pipe);
 953                 usb_clear_halt(serial->dev, port->read_urb->pipe);
 954         } else {
 955                 /* reset upstream data pipes */
 956                 if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
 957                         pl2303_vendor_write(serial, PL2303_HXN_RESET_REG,
 958                                         PL2303_HXN_RESET_UPSTREAM_PIPE |
 959                                         PL2303_HXN_RESET_DOWNSTREAM_PIPE);
 960                 } else {
 961                         pl2303_vendor_write(serial, 8, 0);
 962                         pl2303_vendor_write(serial, 9, 0);
 963                 }
 964         }
 965
 966         /* Setup termios */
 967         if (tty)
 968                 pl2303_set_termios(tty, port, NULL);
 969
 970         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 971         if (result) {
 972                 dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
 973                         result);
 974                 return result;
 975         }
 976
 977         result = usb_serial_generic_open(tty, port);
 978         if (result) {
 979                 usb_kill_urb(port->interrupt_in_urb);
 980                 return result;
 981         }
 982
 983         return 0;
 984 }
 985
 986 static int pl2303_tiocmset(struct tty_struct *tty,
 987                            unsigned int set, unsigned int clear)
 988 {
 989         struct usb_serial_port *port = tty->driver_data;
 990         struct pl2303_private *priv = usb_get_serial_port_data(port);
 991         unsigned long flags;
 992         u8 control;
 993         int ret;
 994
 995         spin_lock_irqsave(&priv->lock, flags);
 996         if (set & TIOCM_RTS)
 997                 priv->line_control |= CONTROL_RTS;
 998         if (set & TIOCM_DTR)
 999                 priv->line_control |= CONTROL_DTR;
1000         if (clear & TIOCM_RTS)
1001                 priv->line_control &= ~CONTROL_RTS;
1002         if (clear & TIOCM_DTR)
1003                 priv->line_control &= ~CONTROL_DTR;
1004         control = priv->line_control;
1005         spin_unlock_irqrestore(&priv->lock, flags);
1006
1007         ret = pl2303_set_control_lines(port, control);
1008         if (ret)
1009                 return usb_translate_errors(ret);
1010
1011         return 0;
1012 }
1013
1014 static int pl2303_tiocmget(struct tty_struct *tty)
1015 {
1016         struct usb_serial_port *port = tty->driver_data;
1017         struct pl2303_private *priv = usb_get_serial_port_data(port);
1018         unsigned long flags;
1019         unsigned int mcr;
1020         unsigned int status;
1021         unsigned int result;
1022
1023         spin_lock_irqsave(&priv->lock, flags);
1024         mcr = priv->line_control;
1025         status = priv->line_status;
1026         spin_unlock_irqrestore(&priv->lock, flags);
1027
1028         result = ((mcr & CONTROL_DTR)           ? TIOCM_DTR : 0)
1029                   | ((mcr & CONTROL_RTS)        ? TIOCM_RTS : 0)
1030                   | ((status & UART_CTS)        ? TIOCM_CTS : 0)
1031                   | ((status & UART_DSR)        ? TIOCM_DSR : 0)
1032                   | ((status & UART_RING)       ? TIOCM_RI  : 0)
1033                   | ((status & UART_DCD)        ? TIOCM_CD  : 0);
1034
1035         dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
1036
1037         return result;
1038 }
1039
1040 static int pl2303_carrier_raised(struct usb_serial_port *port)
1041 {
1042         struct pl2303_private *priv = usb_get_serial_port_data(port);
1043
1044         if (priv->line_status & UART_DCD)
1045                 return 1;
1046
1047         return 0;
1048 }
1049
1050 static void pl2303_set_break(struct usb_serial_port *port, bool enable)
1051 {
1052         struct usb_serial *serial = port->serial;
1053         u16 state;
1054         int result;
1055
1056         if (enable)
1057                 state = BREAK_ON;
1058         else
1059                 state = BREAK_OFF;
1060
1061         dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
1062                         state == BREAK_OFF ? "off" : "on");
1063
1064         result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1065                                  BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
1066                                  0, NULL, 0, 100);
1067         if (result)
1068                 dev_err(&port->dev, "error sending break = %d\n", result);
1069 }
1070
1071 static void pl2303_break_ctl(struct tty_struct *tty, int state)
1072 {
1073         struct usb_serial_port *port = tty->driver_data;
1074
1075         pl2303_set_break(port, state);
1076 }
1077
1078 static void pl2303_update_line_status(struct usb_serial_port *port,
1079                                       unsigned char *data,
1080                                       unsigned int actual_length)
1081 {
1082         struct usb_serial *serial = port->serial;
1083         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
1084         struct pl2303_private *priv = usb_get_serial_port_data(port);
1085         struct tty_struct *tty;
1086         unsigned long flags;
1087         unsigned int status_idx = UART_STATE_INDEX;
1088         u8 status;
1089         u8 delta;
1090
1091         if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
1092                 status_idx = 0;
1093
1094         if (actual_length < status_idx + 1)
1095                 return;
1096
1097         status = data[status_idx];
1098
1099         /* Save off the uart status for others to look at */
1100         spin_lock_irqsave(&priv->lock, flags);
1101         delta = priv->line_status ^ status;
1102         priv->line_status = status;
1103         spin_unlock_irqrestore(&priv->lock, flags);
1104
1105         if (status & UART_BREAK_ERROR)
1106                 usb_serial_handle_break(port);
1107
1108         if (delta & UART_STATE_MSR_MASK) {
1109                 if (delta & UART_CTS)
1110                         port->icount.cts++;
1111                 if (delta & UART_DSR)
1112                         port->icount.dsr++;
1113                 if (delta & UART_RING)
1114                         port->icount.rng++;
1115                 if (delta & UART_DCD) {
1116                         port->icount.dcd++;
1117                         tty = tty_port_tty_get(&port->port);
1118                         if (tty) {
1119                                 usb_serial_handle_dcd_change(port, tty,
1120                                                         status & UART_DCD);
1121                                 tty_kref_put(tty);
1122                         }
1123                 }
1124
1125                 wake_up_interruptible(&port->port.delta_msr_wait);
1126         }
1127 }
1128
1129 static void pl2303_read_int_callback(struct urb *urb)
1130 {
1131         struct usb_serial_port *port =  urb->context;
1132         unsigned char *data = urb->transfer_buffer;
1133         unsigned int actual_length = urb->actual_length;
1134         int status = urb->status;
1135         int retval;
1136
1137         switch (status) {
1138         case 0:
1139                 /* success */
1140                 break;
1141         case -ECONNRESET:
1142         case -ENOENT:
1143         case -ESHUTDOWN:
1144                 /* this urb is terminated, clean up */
1145                 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
1146                         __func__, status);
1147                 return;
1148         default:
1149                 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
1150                         __func__, status);
1151                 goto exit;
1152         }
1153
1154         usb_serial_debug_data(&port->dev, __func__,
1155                               urb->actual_length, urb->transfer_buffer);
1156
1157         pl2303_update_line_status(port, data, actual_length);
1158
1159 exit:
1160         retval = usb_submit_urb(urb, GFP_ATOMIC);
1161         if (retval) {
1162                 dev_err(&port->dev,
1163                         "%s - usb_submit_urb failed with result %d\n",
1164                         __func__, retval);
1165         }
1166 }
1167
1168 static void pl2303_process_read_urb(struct urb *urb)
1169 {
1170         struct usb_serial_port *port = urb->context;
1171         struct pl2303_private *priv = usb_get_serial_port_data(port);
1172         unsigned char *data = urb->transfer_buffer;
1173         char tty_flag = TTY_NORMAL;
1174         unsigned long flags;
1175         u8 line_status;
1176         int i;
1177
1178         /* update line status */
1179         spin_lock_irqsave(&priv->lock, flags);
1180         line_status = priv->line_status;
1181         priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
1182         spin_unlock_irqrestore(&priv->lock, flags);
1183
1184         if (!urb->actual_length)
1185                 return;
1186
1187         /*
1188          * Break takes precedence over parity, which takes precedence over
1189          * framing errors.
1190          */
1191         if (line_status & UART_BREAK_ERROR)
1192                 tty_flag = TTY_BREAK;
1193         else if (line_status & UART_PARITY_ERROR)
1194                 tty_flag = TTY_PARITY;
1195         else if (line_status & UART_FRAME_ERROR)
1196                 tty_flag = TTY_FRAME;
1197
1198         if (tty_flag != TTY_NORMAL)
1199                 dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
1200                                                                 tty_flag);
1201         /* overrun is special, not associated with a char */
1202         if (line_status & UART_OVERRUN_ERROR)
1203                 tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1204
1205         if (port->sysrq) {
1206                 for (i = 0; i < urb->actual_length; ++i)
1207                         if (!usb_serial_handle_sysrq_char(port, data[i]))
1208                                 tty_insert_flip_char(&port->port, data[i],
1209                                                 tty_flag);
1210         } else {
1211                 tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
1212                                                         urb->actual_length);
1213         }
1214
1215         tty_flip_buffer_push(&port->port);
1216 }
1217
1218 static struct usb_serial_driver pl2303_device = {
1219         .driver = {
1220                 .owner =        THIS_MODULE,
1221                 .name =         "pl2303",
1222         },
1223         .id_table =             id_table,
1224         .num_bulk_in =          1,
1225         .num_bulk_out =         1,
1226         .num_interrupt_in =     0,      /* see pl2303_calc_num_ports */
1227         .bulk_in_size =         256,
1228         .bulk_out_size =        256,
1229         .open =                 pl2303_open,
1230         .close =                pl2303_close,
1231         .dtr_rts =              pl2303_dtr_rts,
1232         .carrier_raised =       pl2303_carrier_raised,
1233         .break_ctl =            pl2303_break_ctl,
1234         .set_termios =          pl2303_set_termios,
1235         .tiocmget =             pl2303_tiocmget,
1236         .tiocmset =             pl2303_tiocmset,
1237         .tiocmiwait =           usb_serial_generic_tiocmiwait,
1238         .process_read_urb =     pl2303_process_read_urb,
1239         .read_int_callback =    pl2303_read_int_callback,
1240         .probe =                pl2303_probe,
1241         .calc_num_ports =       pl2303_calc_num_ports,
1242         .attach =               pl2303_startup,
1243         .release =              pl2303_release,
1244         .port_probe =           pl2303_port_probe,
1245         .port_remove =          pl2303_port_remove,
1246 };
1247
1248 static struct usb_serial_driver * const serial_drivers[] = {
1249         &pl2303_device, NULL
1250 };
1251
1252 module_usb_serial_driver(serial_drivers, id_table);
1253
1254 MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
1255 MODULE_LICENSE("GPL v2");