Linux下安装USB转串口驱动（PL2303）

主机:Gentoo Linux 11.2
内核版本：Linux 3.0.6
原创作品，转载请标明出处http://blog.csdn.net/yming0221/article/details/7194988
以前在Ubuntu下USB转串口驱动已经编译进内核，而编译的Gentoo内核没有编译进去，这里将内核中PL2303驱动 copy出来单独编译出pl2303.ko然后将其复制进/var/lib/(内核版本)/drivers/usb/serial/目录下
然后使用命令
depmod
modprobe pl2303
然后将usb转串口接口插入usb，使用命令查看dmesg | tail查看如下



查看内核中驱动，看到usbserial.ko驱动，下面单独编译pl2303.ko
从内核中拷贝的pl2303.h
/*
* Prolific PL2303 USB to serial adaptor driver header file
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
*/

#define BENQ_VENDOR_ID 0x04a5
#define BENQ_PRODUCT_ID_S81 0x4027

#define PL2303_VENDOR_ID 0x067b
#define PL2303_PRODUCT_ID 0x2303
#define PL2303_PRODUCT_ID_RSAQ2 0x04bb
#define PL2303_PRODUCT_ID_DCU11 0x1234
#define PL2303_PRODUCT_ID_PHAROS 0xaaa0
#define PL2303_PRODUCT_ID_RSAQ3 0xaaa2
#define PL2303_PRODUCT_ID_ALDIGA 0x0611
#define PL2303_PRODUCT_ID_MMX 0x0612
#define PL2303_PRODUCT_ID_GPRS 0x0609
#define PL2303_PRODUCT_ID_HCR331 0x331a
#define PL2303_PRODUCT_ID_MOTOROLA 0x0307

#define ATEN_VENDOR_ID 0x0557
#define ATEN_VENDOR_ID2 0x0547
#define ATEN_PRODUCT_ID 0x2008

#define IODATA_VENDOR_ID 0x04bb
#define IODATA_PRODUCT_ID 0x0a03
#define IODATA_PRODUCT_ID_RSAQ5 0x0a0e

#define ELCOM_VENDOR_ID 0x056e
#define ELCOM_PRODUCT_ID 0x5003
#define ELCOM_PRODUCT_ID_UCSGT 0x5004

#define ITEGNO_VENDOR_ID 0x0eba
#define ITEGNO_PRODUCT_ID 0x1080
#define ITEGNO_PRODUCT_ID_2080 0x2080

#define MA620_VENDOR_ID 0x0df7
#define MA620_PRODUCT_ID 0x0620

#define RATOC_VENDOR_ID 0x0584
#define RATOC_PRODUCT_ID 0xb000

#define TRIPP_VENDOR_ID 0x2478
#define TRIPP_PRODUCT_ID 0x2008

#define RADIOSHACK_VENDOR_ID 0x1453
#define RADIOSHACK_PRODUCT_ID 0x4026

#define DCU10_VENDOR_ID 0x0731
#define DCU10_PRODUCT_ID 0x0528

#define SITECOM_VENDOR_ID 0x6189
#define SITECOM_PRODUCT_ID 0x2068

/* Alcatel OT535/735 USB cable */
#define ALCATEL_VENDOR_ID 0x11f7
#define ALCATEL_PRODUCT_ID 0x02df

/* Samsung I330 phone cradle */
#define SAMSUNG_VENDOR_ID 0x04e8
#define SAMSUNG_PRODUCT_ID 0x8001

#define SIEMENS_VENDOR_ID 0x11f5
#define SIEMENS_PRODUCT_ID_SX1 0x0001
#define SIEMENS_PRODUCT_ID_X65 0x0003
#define SIEMENS_PRODUCT_ID_X75 0x0004
#define SIEMENS_PRODUCT_ID_EF81 0x0005

#define SYNTECH_VENDOR_ID 0x0745
#define SYNTECH_PRODUCT_ID 0x0001

/* Nokia CA-42 Cable */
#define NOKIA_CA42_VENDOR_ID 0x078b
#define NOKIA_CA42_PRODUCT_ID 0x1234

/* CA-42 CLONE Cable www.ca-42.com chipset: Prolific Technology Inc */
#define CA_42_CA42_VENDOR_ID 0x10b5
#define CA_42_CA42_PRODUCT_ID 0xac70

#define SAGEM_VENDOR_ID 0x079b
#define SAGEM_PRODUCT_ID 0x0027

/* Leadtek GPS 9531 (ID 0413:2101) */
#define LEADTEK_VENDOR_ID 0x0413
#define LEADTEK_9531_PRODUCT_ID 0x2101

/* USB GSM cable from Speed Dragon Multimedia, Ltd */
#define SPEEDDRAGON_VENDOR_ID 0x0e55
#define SPEEDDRAGON_PRODUCT_ID 0x110b

/* DATAPILOT Universal-2 Phone Cable */
#define DATAPILOT_U2_VENDOR_ID 0x0731
#define DATAPILOT_U2_PRODUCT_ID 0x2003

/* Belkin "F5U257" Serial Adapter */
#define BELKIN_VENDOR_ID 0x050d
#define BELKIN_PRODUCT_ID 0x0257

/* Alcor Micro Corp. USB 2.0 TO RS-232 */
#define ALCOR_VENDOR_ID 0x058F
#define ALCOR_PRODUCT_ID 0x9720

/* Willcom WS002IN Data Driver (by NetIndex Inc.) */
#define WS002IN_VENDOR_ID 0x11f6
#define WS002IN_PRODUCT_ID 0x2001

/* Corega CG-USBRS232R Serial Adapter */
#define COREGA_VENDOR_ID 0x07aa
#define COREGA_PRODUCT_ID 0x002a

/* Y.C. Cable U.S.A., Inc - USB to RS-232 */
#define YCCABLE_VENDOR_ID 0x05ad
#define YCCABLE_PRODUCT_ID 0x0fba

/* "Superial" USB - Serial */
#define SUPERIAL_VENDOR_ID 0x5372
#define SUPERIAL_PRODUCT_ID 0x2303

/* Hewlett-Packard LD220-HP POS Pole Display */
#define HP_VENDOR_ID 0x03f0
#define HP_LD220_PRODUCT_ID 0x3524

/* Cressi Edy (diving computer) PC interface */
#define CRESSI_VENDOR_ID 0x04b8
#define CRESSI_EDY_PRODUCT_ID 0x0521

/* Zeagle dive computer interface */
#define ZEAGLE_VENDOR_ID 0x04b8
#define ZEAGLE_N2ITION3_PRODUCT_ID 0x0522

/* Sony, USB data cable for CMD-Jxx mobile phones */
#define SONY_VENDOR_ID 0x054c
#define SONY_QN3USB_PRODUCT_ID 0x0437

/* Sanwa KB-USB2 multimeter cable (ID: 11ad:0001) */
#define SANWA_VENDOR_ID 0x11ad
#define SANWA_PRODUCT_ID 0x0001

/* ADLINK ND-6530 RS232,RS485 and RS422 adapter */
#define ADLINK_VENDOR_ID 0x0b63
#define ADLINK_ND6530_PRODUCT_ID 0x6530

/* WinChipHead USB->RS 232 adapter */
#define WINCHIPHEAD_VENDOR_ID 0x4348
#define WINCHIPHEAD_USBSER_PRODUCT_ID 0x5523

pl2303.c代码

/*
* Prolific PL2303 USB to serial adaptor driver
*
* Copyright (C) 2001-2007 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (C) 2003 IBM Corp.
*
* Original driver for 2.2.x by anonymous
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*
* See Documentation/usb/usb-serial.txt for more information on using this
* driver
*
*/

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "pl2303.h"

/*
* Version Information
*/
#define DRIVER_DESC "Prolific PL2303 USB to serial adaptor driver"

static int debug;

#define PL2303_CLOSING_WAIT (30*HZ)

static const struct usb_device_id id_table[] = {
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_PHAROS) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ALDIGA) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MMX) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GPRS) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_HCR331) },
{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MOTOROLA) },
{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID_RSAQ5) },
{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID) },
{ USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
{ USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
{ USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
{ USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
{ USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
{ USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
{ USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
{ USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
{ USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
{ USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_PRODUCT_ID) },
{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1) },
{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65) },
{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75) },
{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81) },
{ USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
{ USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
{ USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
{ USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
{ USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
{ USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
{ USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
{ USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
{ USB_DEVICE(ALCOR_VENDOR_ID, ALCOR_PRODUCT_ID) },
{ USB_DEVICE(WS002IN_VENDOR_ID, WS002IN_PRODUCT_ID) },
{ USB_DEVICE(COREGA_VENDOR_ID, COREGA_PRODUCT_ID) },
{ USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
{ USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
{ USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
{ USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
{ USB_DEVICE(WINCHIPHEAD_VENDOR_ID, WINCHIPHEAD_USBSER_PRODUCT_ID) },
{ } /* Terminating entry */
};

MODULE_DEVICE_TABLE(usb, id_table);

static struct usb_driver pl2303_driver = {
.name = "pl2303",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = id_table,
.suspend = usb_serial_suspend,
.resume = usb_serial_resume,
.no_dynamic_id = 1,
.supports_autosuspend = 1,
};

#define SET_LINE_REQUEST_TYPE 0x21
#define SET_LINE_REQUEST 0x20

#define SET_CONTROL_REQUEST_TYPE 0x21
#define SET_CONTROL_REQUEST 0x22
#define CONTROL_DTR 0x01
#define CONTROL_RTS 0x02

#define BREAK_REQUEST_TYPE 0x21
#define BREAK_REQUEST 0x23
#define BREAK_ON 0xffff
#define BREAK_OFF 0x0000

#define GET_LINE_REQUEST_TYPE 0xa1
#define GET_LINE_REQUEST 0x21

#define VENDOR_WRITE_REQUEST_TYPE 0x40
#define VENDOR_WRITE_REQUEST 0x01

#define VENDOR_READ_REQUEST_TYPE 0xc0
#define VENDOR_READ_REQUEST 0x01

#define UART_STATE 0x08
#define UART_STATE_TRANSIENT_MASK 0x74
#define UART_DCD 0x01
#define UART_DSR 0x02
#define UART_BREAK_ERROR 0x04
#define UART_RING 0x08
#define UART_FRAME_ERROR 0x10
#define UART_PARITY_ERROR 0x20
#define UART_OVERRUN_ERROR 0x40
#define UART_CTS 0x80

enum pl2303_type {
type_0, /* don't know the difference between type 0 and */
type_1, /* type 1, until someone from prolific tells us... */
HX, /* HX version of the pl2303 chip */
};

struct pl2303_private {
spinlock_t lock;
wait_queue_head_t delta_msr_wait;
u8 line_control;
u8 line_status;
enum pl2303_type type;
};

static int pl2303_vendor_read(__u16 value, __u16 index,
struct usb_serial *serial, unsigned char *buf)
{
int res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
value, index, buf, 1, 100);
dbg("0x%x:0x%x:0x%x:0x%x %d - %x", VENDOR_READ_REQUEST_TYPE,
VENDOR_READ_REQUEST, value, index, res, buf[0]);
return res;
}

static int pl2303_vendor_write(__u16 value, __u16 index,
struct usb_serial *serial)
{
int res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
VENDOR_WRITE_REQUEST, VENDOR_WRITE_REQUEST_TYPE,
value, index, NULL, 0, 100);
dbg("0x%x:0x%x:0x%x:0x%x %d", VENDOR_WRITE_REQUEST_TYPE,
VENDOR_WRITE_REQUEST, value, index, res);
return res;
}

static int pl2303_startup(struct usb_serial *serial)
{
struct pl2303_private *priv;
enum pl2303_type type = type_0;
unsigned char *buf;
int i;

buf = kmalloc(10, GFP_KERNEL);
if (buf == NULL)
return -ENOMEM;

if (serial->dev->descriptor.bDeviceClass == 0x02)
type = type_0;
else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
type = HX;
else if (serial->dev->descriptor.bDeviceClass == 0x00)
type = type_1;
else if (serial->dev->descriptor.bDeviceClass == 0xFF)
type = type_1;
dbg("device type: %d", type);

for (i = 0; i < serial->num_ports; ++i) {
priv = kzalloc(sizeof(struct pl2303_private), GFP_KERNEL);
if (!priv)
goto cleanup;
spin_lock_init(&priv->lock);
init_waitqueue_head(&priv->delta_msr_wait);
priv->type = type;
usb_set_serial_port_data(serial->port[i], priv);
}

pl2303_vendor_read(0x8484, 0, serial, buf);
pl2303_vendor_write(0x0404, 0, serial);
pl2303_vendor_read(0x8484, 0, serial, buf);
pl2303_vendor_read(0x8383, 0, serial, buf);
pl2303_vendor_read(0x8484, 0, serial, buf);
pl2303_vendor_write(0x0404, 1, serial);
pl2303_vendor_read(0x8484, 0, serial, buf);
pl2303_vendor_read(0x8383, 0, serial, buf);
pl2303_vendor_write(0, 1, serial);
pl2303_vendor_write(1, 0, serial);
if (type == HX)
pl2303_vendor_write(2, 0x44, serial);
else
pl2303_vendor_write(2, 0x24, serial);

kfree(buf);
return 0;

cleanup:
kfree(buf);
for (--i; i >= 0; --i) {
priv = usb_get_serial_port_data(serial->port[i]);
kfree(priv);
usb_set_serial_port_data(serial->port[i], NULL);
}
return -ENOMEM;
}

static int set_control_lines(struct usb_device *dev, u8 value)
{
int retval;

retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
value, 0, NULL, 0, 100);
dbg("%s - value = %d, retval = %d", __func__, value, retval);
return retval;
}

static void pl2303_set_termios(struct tty_struct *tty,
struct usb_serial_port *port, struct ktermios *old_termios)
{
struct usb_serial *serial = port->serial;
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
unsigned int cflag;
unsigned char *buf;
int baud;
int i;
u8 control;
const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400, 3600,
4800, 7200, 9600, 14400, 19200, 28800, 38400,
57600, 115200, 230400, 460800, 614400,
921600, 1228800, 2457600, 3000000, 6000000 };
int baud_floor, baud_ceil;
int k;

dbg("%s - port %d", __func__, port->number);

/* The PL2303 is reported to lose bytes if you change
serial settings even to the same values as before. Thus
we actually need to filter in this specific case */

if (!tty_termios_hw_change(tty->termios, old_termios))
return;

cflag = tty->termios->c_cflag;

buf = kzalloc(7, GFP_KERNEL);
if (!buf) {
dev_err(&port->dev, "%s - out of memory.\n", __func__);
/* Report back no change occurred */
*tty->termios = *old_termios;
return;
}

i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
0, 0, buf, 7, 100);
dbg("0xa1:0x21:0:0 %d - %x %x %x %x %x %x %x", i,
buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);

if (cflag & CSIZE) {
switch (cflag & CSIZE) {
case CS5:
buf[6] = 5;
break;
case CS6:
buf[6] = 6;
break;
case CS7:
buf[6] = 7;
break;
default:
case CS8:
buf[6] = 8;
break;
}
dbg("%s - data bits = %d", __func__, buf[6]);
}

/* For reference buf[0]:buf[3] baud rate value */
/* NOTE: Only the values defined in baud_sup are supported !
* => if unsupported values are set, the PL2303 seems to use
* 9600 baud (at least my PL2303X always does)
*/
baud = tty_get_baud_rate(tty);
dbg("%s - baud requested = %d", __func__, baud);
if (baud) {
/* Set baudrate to nearest supported value */
for (k=0; k<ARRAY_SIZE(baud_sup); k++) {
if (baud_sup[k] / baud) {
baud_ceil = baud_sup[k];
if (k==0) {
baud = baud_ceil;
} else {
baud_floor = baud_sup[k-1];
if ((baud_ceil % baud)
> (baud % baud_floor))
baud = baud_floor;
else
baud = baud_ceil;
}
break;
}
}
if (baud > 1228800) {
/* type_0, type_1 only support up to 1228800 baud */
if (priv->type != HX)
baud = 1228800;
else if (baud > 6000000)
baud = 6000000;
}
dbg("%s - baud set = %d", __func__, baud);
if (baud <= 115200) {
buf[0] = baud & 0xff;
buf[1] = (baud >> 8) & 0xff;
buf[2] = (baud >> 16) & 0xff;
buf[3] = (baud >> 24) & 0xff;
} else {
/* apparently the formula for higher speeds is:
* baudrate = 12M * 32 / (2^buf[1]) / buf[0]
*/
unsigned tmp = 12*1000*1000*32 / baud;
buf[3] = 0x80;
buf[2] = 0;
buf[1] = (tmp >= 256);
while (tmp >= 256) {
tmp >>= 2;
buf[1] <<= 1;
}
if (tmp > 256) {
tmp %= 256;
}
buf[0] = tmp;
}
}

/* For reference buf[4]=0 is 1 stop bits */
/* For reference buf[4]=1 is 1.5 stop bits */
/* For reference buf[4]=2 is 2 stop bits */
if (cflag & CSTOPB) {
/* NOTE: Comply with "real" UARTs / RS232:
* use 1.5 instead of 2 stop bits with 5 data bits
*/
if ((cflag & CSIZE) == CS5) {
buf[4] = 1;
dbg("%s - stop bits = 1.5", __func__);
} else {
buf[4] = 2;
dbg("%s - stop bits = 2", __func__);
}
} else {
buf[4] = 0;
dbg("%s - stop bits = 1", __func__);
}

if (cflag & PARENB) {
/* For reference buf[5]=0 is none parity */
/* For reference buf[5]=1 is odd parity */
/* For reference buf[5]=2 is even parity */
/* For reference buf[5]=3 is mark parity */
/* For reference buf[5]=4 is space parity */
if (cflag & PARODD) {
if (cflag & CMSPAR) {
buf[5] = 3;
dbg("%s - parity = mark", __func__);
} else {
buf[5] = 1;
dbg("%s - parity = odd", __func__);
}
} else {
if (cflag & CMSPAR) {
buf[5] = 4;
dbg("%s - parity = space", __func__);
} else {
buf[5] = 2;
dbg("%s - parity = even", __func__);
}
}
} else {
buf[5] = 0;
dbg("%s - parity = none", __func__);
}

i = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
0, 0, buf, 7, 100);
dbg("0x21:0x20:0:0 %d", i);

/* change control lines if we are switching to or from B0 */
spin_lock_irqsave(&priv->lock, flags);
control = priv->line_control;
if ((cflag & CBAUD) == B0)
priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
else
priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
if (control != priv->line_control) {
control = priv->line_control;
spin_unlock_irqrestore(&priv->lock, flags);
set_control_lines(serial->dev, control);
} else {
spin_unlock_irqrestore(&priv->lock, flags);
}

buf[0] = buf[1] = buf[2] = buf[3] = buf[4] = buf[5] = buf[6] = 0;

i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
0, 0, buf, 7, 100);
dbg("0xa1:0x21:0:0 %d - %x %x %x %x %x %x %x", i,
buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);

if (cflag & CRTSCTS) {
if (priv->type == HX)
pl2303_vendor_write(0x0, 0x61, serial);
else
pl2303_vendor_write(0x0, 0x41, serial);
} else {
pl2303_vendor_write(0x0, 0x0, serial);
}

/* Save resulting baud rate */
if (baud)
tty_encode_baud_rate(tty, baud, baud);

kfree(buf);
}

static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
{
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
u8 control;

spin_lock_irqsave(&priv->lock, flags);
/* Change DTR and RTS */
if (on)
priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
else
priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
control = priv->line_control;
spin_unlock_irqrestore(&priv->lock, flags);
set_control_lines(port->serial->dev, control);
}

static void pl2303_close(struct usb_serial_port *port)
{
dbg("%s - port %d", __func__, port->number);

usb_serial_generic_close(port);
usb_kill_urb(port->interrupt_in_urb);
}

static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
{
struct ktermios tmp_termios;
struct usb_serial *serial = port->serial;
struct pl2303_private *priv = usb_get_serial_port_data(port);
int result;

dbg("%s - port %d", __func__, port->number);

if (priv->type != HX) {
usb_clear_halt(serial->dev, port->write_urb->pipe);
usb_clear_halt(serial->dev, port->read_urb->pipe);
} else {
/* reset upstream data pipes */
pl2303_vendor_write(8, 0, serial);
pl2303_vendor_write(9, 0, serial);
}

/* Setup termios */
if (tty)
pl2303_set_termios(tty, port, &tmp_termios);

dbg("%s - submitting read urb", __func__);
result = usb_serial_generic_submit_read_urb(port, GFP_KERNEL);
if (result) {
pl2303_close(port);
return -EPROTO;
}

dbg("%s - submitting interrupt urb", __func__);
result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
if (result) {
dev_err(&port->dev, "%s - failed submitting interrupt urb,"
" error %d\n", __func__, result);
pl2303_close(port);
return -EPROTO;
}
port->port.drain_delay = 256;
return 0;
}

static int pl2303_tiocmset(struct tty_struct *tty,
unsigned int set, unsigned int clear)
{
struct usb_serial_port *port = tty->driver_data;
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
u8 control;

if (!usb_get_intfdata(port->serial->interface))
return -ENODEV;

spin_lock_irqsave(&priv->lock, flags);
if (set & TIOCM_RTS)
priv->line_control |= CONTROL_RTS;
if (set & TIOCM_DTR)
priv->line_control |= CONTROL_DTR;
if (clear & TIOCM_RTS)
priv->line_control &= ~CONTROL_RTS;
if (clear & TIOCM_DTR)
priv->line_control &= ~CONTROL_DTR;
control = priv->line_control;
spin_unlock_irqrestore(&priv->lock, flags);

return set_control_lines(port->serial->dev, control);
}

static int pl2303_tiocmget(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
unsigned int mcr;
unsigned int status;
unsigned int result;

dbg("%s (%d)", __func__, port->number);

if (!usb_get_intfdata(port->serial->interface))
return -ENODEV;

spin_lock_irqsave(&priv->lock, flags);
mcr = priv->line_control;
status = priv->line_status;
spin_unlock_irqrestore(&priv->lock, flags);

result = ((mcr & CONTROL_DTR) ? TIOCM_DTR : 0)
| ((mcr & CONTROL_RTS) ? TIOCM_RTS : 0)
| ((status & UART_CTS) ? TIOCM_CTS : 0)
| ((status & UART_DSR) ? TIOCM_DSR : 0)
| ((status & UART_RING) ? TIOCM_RI : 0)
| ((status & UART_DCD) ? TIOCM_CD : 0);

dbg("%s - result = %x", __func__, result);

return result;
}

static int pl2303_carrier_raised(struct usb_serial_port *port)
{
struct pl2303_private *priv = usb_get_serial_port_data(port);
if (priv->line_status & UART_DCD)
return 1;
return 0;
}

static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
{
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
unsigned int prevstatus;
unsigned int status;
unsigned int changed;

spin_lock_irqsave(&priv->lock, flags);
prevstatus = priv->line_status;
spin_unlock_irqrestore(&priv->lock, flags);

while (1) {
interruptible_sleep_on(&priv->delta_msr_wait);
/* see if a signal did it */
if (signal_pending(current))
return -ERESTARTSYS;

spin_lock_irqsave(&priv->lock, flags);
status = priv->line_status;
spin_unlock_irqrestore(&priv->lock, flags);

changed = prevstatus ^ status;

if (((arg & TIOCM_RNG) && (changed & UART_RING)) ||
((arg & TIOCM_DSR) && (changed & UART_DSR)) ||
((arg & TIOCM_CD) && (changed & UART_DCD)) ||
((arg & TIOCM_CTS) && (changed & UART_CTS))) {
return 0;
}
prevstatus = status;
}
/* NOTREACHED */
return 0;
}

static int pl2303_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
{
struct serial_struct ser;
struct usb_serial_port *port = tty->driver_data;
dbg("%s (%d) cmd = 0x%04x", __func__, port->number, cmd);

switch (cmd) {
case TIOCGSERIAL:
memset(&ser, 0, sizeof ser);
ser.type = PORT_16654;
ser.line = port->serial->minor;
ser.port = port->number;
ser.baud_base = 460800;

if (copy_to_user((void __user *)arg, &ser, sizeof ser))
return -EFAULT;

return 0;

case TIOCMIWAIT:
dbg("%s (%d) TIOCMIWAIT", __func__, port->number);
return wait_modem_info(port, arg);
default:
dbg("%s not supported = 0x%04x", __func__, cmd);
break;
}
return -ENOIOCTLCMD;
}

static void pl2303_break_ctl(struct tty_struct *tty, int break_state)
{
struct usb_serial_port *port = tty->driver_data;
struct usb_serial *serial = port->serial;
u16 state;
int result;

dbg("%s - port %d", __func__, port->number);

if (break_state == 0)
state = BREAK_OFF;
else
state = BREAK_ON;
dbg("%s - turning break %s", __func__,
state == BREAK_OFF ? "off" : "on");

result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
0, NULL, 0, 100);
if (result)
dbg("%s - error sending break = %d", __func__, result);
}

static void pl2303_release(struct usb_serial *serial)
{
int i;
struct pl2303_private *priv;

dbg("%s", __func__);

for (i = 0; i < serial->num_ports; ++i) {
priv = usb_get_serial_port_data(serial->port[i]);
kfree(priv);
}
}

static void pl2303_update_line_status(struct usb_serial_port *port,
unsigned char *data,
unsigned int actual_length)
{

struct pl2303_private *priv = usb_get_serial_port_data(port);
struct tty_struct *tty;
unsigned long flags;
u8 status_idx = UART_STATE;
u8 length = UART_STATE + 1;
u8 prev_line_status;
u16 idv, idp;

idv = le16_to_cpu(port->serial->dev->descriptor.idVendor);
idp = le16_to_cpu(port->serial->dev->descriptor.idProduct);

if (idv == SIEMENS_VENDOR_ID) {
if (idp == SIEMENS_PRODUCT_ID_X65 ||
idp == SIEMENS_PRODUCT_ID_SX1 ||
idp == SIEMENS_PRODUCT_ID_X75) {

length = 1;
status_idx = 0;
}
}

if (actual_length < length)
return;

/* Save off the uart status for others to look at */
spin_lock_irqsave(&priv->lock, flags);
prev_line_status = priv->line_status;
priv->line_status = data[status_idx];
spin_unlock_irqrestore(&priv->lock, flags);
if (priv->line_status & UART_BREAK_ERROR)
usb_serial_handle_break(port);
wake_up_interruptible(&priv->delta_msr_wait);

tty = tty_port_tty_get(&port->port);
if (!tty)
return;
if ((priv->line_status ^ prev_line_status) & UART_DCD)
usb_serial_handle_dcd_change(port, tty,
priv->line_status & UART_DCD);
tty_kref_put(tty);
}

static void pl2303_read_int_callback(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
unsigned char *data = urb->transfer_buffer;
unsigned int actual_length = urb->actual_length;
int status = urb->status;
int retval;

dbg("%s (%d)", __func__, port->number);

switch (status) {
case 0:
/* success */
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d", __func__,
status);
return;
default:
dbg("%s - nonzero urb status received: %d", __func__,
status);
goto exit;
}

usb_serial_debug_data(debug, &port->dev, __func__,
urb->actual_length, urb->transfer_buffer);

pl2303_update_line_status(port, data, actual_length);

exit:
retval = usb_submit_urb(urb, GFP_ATOMIC);
if (retval)
dev_err(&urb->dev->dev,
"%s - usb_submit_urb failed with result %d\n",
__func__, retval);
}

static void pl2303_process_read_urb(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
struct pl2303_private *priv = usb_get_serial_port_data(port);
struct tty_struct *tty;
unsigned char *data = urb->transfer_buffer;
char tty_flag = TTY_NORMAL;
unsigned long flags;
u8 line_status;
int i;

/* update line status */
spin_lock_irqsave(&priv->lock, flags);
line_status = priv->line_status;
priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
spin_unlock_irqrestore(&priv->lock, flags);
wake_up_interruptible(&priv->delta_msr_wait);

if (!urb->actual_length)
return;

tty = tty_port_tty_get(&port->port);
if (!tty)
return;

/* break takes precedence over parity, */
/* which takes precedence over framing errors */
if (line_status & UART_BREAK_ERROR)
tty_flag = TTY_BREAK;
else if (line_status & UART_PARITY_ERROR)
tty_flag = TTY_PARITY;
else if (line_status & UART_FRAME_ERROR)
tty_flag = TTY_FRAME;
dbg("%s - tty_flag = %d", __func__, tty_flag);

/* overrun is special, not associated with a char */
if (line_status & UART_OVERRUN_ERROR)
tty_insert_flip_char(tty, 0, TTY_OVERRUN);

if (port->port.console && port->sysrq) {
for (i = 0; i < urb->actual_length; ++i)
if (!usb_serial_handle_sysrq_char(port, data[i]))
tty_insert_flip_char(tty, data[i], tty_flag);
} else {
tty_insert_flip_string_fixed_flag(tty, data, tty_flag,
urb->actual_length);
}

tty_flip_buffer_push(tty);
tty_kref_put(tty);
}

/* All of the device info needed for the PL2303 SIO serial converter */
static struct usb_serial_driver pl2303_device = {
.driver = {
.owner = THIS_MODULE,
.name = "pl2303",
},
.id_table = id_table,
.usb_driver = &pl2303_driver,
.num_ports = 1,
.bulk_in_size = 256,
.bulk_out_size = 256,
.open = pl2303_open,
.close = pl2303_close,
.dtr_rts = pl2303_dtr_rts,
.carrier_raised = pl2303_carrier_raised,
.ioctl = pl2303_ioctl,
.break_ctl = pl2303_break_ctl,
.set_termios = pl2303_set_termios,
.tiocmget = pl2303_tiocmget,
.tiocmset = pl2303_tiocmset,
.process_read_urb = pl2303_process_read_urb,
.read_int_callback = pl2303_read_int_callback,
.attach = pl2303_startup,
.release = pl2303_release,
};

static int __init pl2303_init(void)
{
int retval;

retval = usb_serial_register(&pl2303_device);
if (retval)
goto failed_usb_serial_register;
retval = usb_register(&pl2303_driver);
if (retval)
goto failed_usb_register;
printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
return 0;
failed_usb_register:
usb_serial_deregister(&pl2303_device);
failed_usb_serial_register:
return retval;
}

static void __exit pl2303_exit(void)
{
usb_deregister(&pl2303_driver);
usb_serial_deregister(&pl2303_device);
}

module_init(pl2303_init);
module_exit(pl2303_exit);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");

Makefile文件：
#KVER = /usr/src/linux
KVER = /lib/modules/`uname -r`/build
CURDIR = $(shell pwd)
# Kernel modules
obj-m := pl2303.o
build: kernel_modules
kernel_modules:
$(MAKE) -C $(KVER) M=$(CURDIR) modules
clean:
$(MAKE) -C $(KVER) M=$(CURDIR) clean