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linux/drivers/usb/serial/pl2303.c

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/*
* Prolific PL2303 USB to serial adaptor driver
*
* Copyright (C) 2001-2004 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 as published by
* the Free Software Foundation; either version 2 of the License.
*
* 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 <asm/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)
#define PL2303_BUF_SIZE 1024
#define PL2303_TMP_BUF_SIZE 1024
struct pl2303_buf {
unsigned int buf_size;
char *buf_buf;
char *buf_get;
char *buf_put;
};
static 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(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
{ 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(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) },
{ } /* 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,
.no_dynamic_id = 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
/* function prototypes for a PL2303 serial converter */
static int pl2303_open (struct usb_serial_port *port, struct file *filp);
static void pl2303_close (struct usb_serial_port *port, struct file *filp);
static void pl2303_set_termios (struct usb_serial_port *port,
struct termios *old);
static int pl2303_ioctl (struct usb_serial_port *port, struct file *file,
unsigned int cmd, unsigned long arg);
static void pl2303_read_int_callback (struct urb *urb, struct pt_regs *regs);
static void pl2303_read_bulk_callback (struct urb *urb, struct pt_regs *regs);
static void pl2303_write_bulk_callback (struct urb *urb, struct pt_regs *regs);
static int pl2303_write (struct usb_serial_port *port,
const unsigned char *buf, int count);
static void pl2303_send (struct usb_serial_port *port);
static int pl2303_write_room(struct usb_serial_port *port);
static int pl2303_chars_in_buffer(struct usb_serial_port *port);
static void pl2303_break_ctl(struct usb_serial_port *port,int break_state);
static int pl2303_tiocmget (struct usb_serial_port *port, struct file *file);
static int pl2303_tiocmset (struct usb_serial_port *port, struct file *file,
unsigned int set, unsigned int clear);
static int pl2303_startup (struct usb_serial *serial);
static void pl2303_shutdown (struct usb_serial *serial);
static struct pl2303_buf *pl2303_buf_alloc(unsigned int size);
static void pl2303_buf_free(struct pl2303_buf *pb);
static void pl2303_buf_clear(struct pl2303_buf *pb);
static unsigned int pl2303_buf_data_avail(struct pl2303_buf *pb);
static unsigned int pl2303_buf_space_avail(struct pl2303_buf *pb);
static unsigned int pl2303_buf_put(struct pl2303_buf *pb, const char *buf,
unsigned int count);
static unsigned int pl2303_buf_get(struct pl2303_buf *pb, char *buf,
unsigned int count);
/* 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,
.num_interrupt_in = NUM_DONT_CARE,
.num_bulk_in = 1,
.num_bulk_out = 1,
.num_ports = 1,
.open = pl2303_open,
.close = pl2303_close,
.write = pl2303_write,
.ioctl = pl2303_ioctl,
.break_ctl = pl2303_break_ctl,
.set_termios = pl2303_set_termios,
.tiocmget = pl2303_tiocmget,
.tiocmset = pl2303_tiocmset,
.read_bulk_callback = pl2303_read_bulk_callback,
.read_int_callback = pl2303_read_int_callback,
.write_bulk_callback = pl2303_write_bulk_callback,
.write_room = pl2303_write_room,
.chars_in_buffer = pl2303_chars_in_buffer,
.attach = pl2303_startup,
.shutdown = pl2303_shutdown,
};
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;
struct pl2303_buf *buf;
int write_urb_in_use;
wait_queue_head_t delta_msr_wait;
u8 line_control;
u8 line_status;
u8 termios_initialized;
enum pl2303_type type;
};
static int pl2303_startup(struct usb_serial *serial)
{
struct pl2303_private *priv;
enum pl2303_type type = type_0;
int i;
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);
priv->buf = pl2303_buf_alloc(PL2303_BUF_SIZE);
if (priv->buf == NULL) {
kfree(priv);
goto cleanup;
}
init_waitqueue_head(&priv->delta_msr_wait);
priv->type = type;
usb_set_serial_port_data(serial->port[i], priv);
}
return 0;
cleanup:
for (--i; i>=0; --i) {
priv = usb_get_serial_port_data(serial->port[i]);
pl2303_buf_free(priv->buf);
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", __FUNCTION__, value, retval);
return retval;
}
static int pl2303_write(struct usb_serial_port *port, const unsigned char *buf,
int count)
{
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
dbg("%s - port %d, %d bytes", __FUNCTION__, port->number, count);
if (!count)
return count;
spin_lock_irqsave(&priv->lock, flags);
count = pl2303_buf_put(priv->buf, buf, count);
spin_unlock_irqrestore(&priv->lock, flags);
pl2303_send(port);
return count;
}
static void pl2303_send(struct usb_serial_port *port)
{
int count, result;
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&priv->lock, flags);
if (priv->write_urb_in_use) {
spin_unlock_irqrestore(&priv->lock, flags);
return;
}
count = pl2303_buf_get(priv->buf, port->write_urb->transfer_buffer,
port->bulk_out_size);
if (count == 0) {
spin_unlock_irqrestore(&priv->lock, flags);
return;
}
priv->write_urb_in_use = 1;
spin_unlock_irqrestore(&priv->lock, flags);
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count,
port->write_urb->transfer_buffer);
port->write_urb->transfer_buffer_length = count;
port->write_urb->dev = port->serial->dev;
result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
if (result) {
dev_err(&port->dev, "%s - failed submitting write urb,"
" error %d\n", __FUNCTION__, result);
priv->write_urb_in_use = 0;
// TODO: reschedule pl2303_send
}
usb_serial_port_softint(port);
}
static int pl2303_write_room(struct usb_serial_port *port)
{
struct pl2303_private *priv = usb_get_serial_port_data(port);
int room = 0;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&priv->lock, flags);
room = pl2303_buf_space_avail(priv->buf);
spin_unlock_irqrestore(&priv->lock, flags);
dbg("%s - returns %d", __FUNCTION__, room);
return room;
}
static int pl2303_chars_in_buffer(struct usb_serial_port *port)
{
struct pl2303_private *priv = usb_get_serial_port_data(port);
int chars = 0;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&priv->lock, flags);
chars = pl2303_buf_data_avail(priv->buf);
spin_unlock_irqrestore(&priv->lock, flags);
dbg("%s - returns %d", __FUNCTION__, chars);
return chars;
}
static void pl2303_set_termios(struct usb_serial_port *port,
struct termios *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;
dbg("%s - port %d", __FUNCTION__, port->number);
if ((!port->tty) || (!port->tty->termios)) {
dbg("%s - no tty structures", __FUNCTION__);
return;
}
spin_lock_irqsave(&priv->lock, flags);
if (!priv->termios_initialized) {
*(port->tty->termios) = tty_std_termios;
port->tty->termios->c_cflag = B9600 | CS8 | CREAD |
HUPCL | CLOCAL;
priv->termios_initialized = 1;
}
spin_unlock_irqrestore(&priv->lock, flags);
cflag = port->tty->termios->c_cflag;
/* check that they really want us to change something */
if (old_termios) {
if ((cflag == old_termios->c_cflag) &&
(RELEVANT_IFLAG(port->tty->termios->c_iflag) ==
RELEVANT_IFLAG(old_termios->c_iflag))) {
dbg("%s - nothing to change...", __FUNCTION__);
return;
}
}
buf = kzalloc(7, GFP_KERNEL);
if (!buf) {
dev_err(&port->dev, "%s - out of memory.\n", __FUNCTION__);
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", __FUNCTION__, buf[6]);
}
baud = 0;
switch (cflag & CBAUD) {
case B0: baud = 0; break;
case B75: baud = 75; break;
case B150: baud = 150; break;
case B300: baud = 300; break;
case B600: baud = 600; break;
case B1200: baud = 1200; break;
case B1800: baud = 1800; break;
case B2400: baud = 2400; break;
case B4800: baud = 4800; break;
case B9600: baud = 9600; break;
case B19200: baud = 19200; break;
case B38400: baud = 38400; break;
case B57600: baud = 57600; break;
case B115200: baud = 115200; break;
case B230400: baud = 230400; break;
case B460800: baud = 460800; break;
default:
dev_err(&port->dev, "pl2303 driver does not support"
" the baudrate requested (fix it)\n");
break;
}
dbg("%s - baud = %d", __FUNCTION__, baud);
if (baud) {
buf[0] = baud & 0xff;
buf[1] = (baud >> 8) & 0xff;
buf[2] = (baud >> 16) & 0xff;
buf[3] = (baud >> 24) & 0xff;
}
/* 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) {
buf[4] = 2;
dbg("%s - stop bits = 2", __FUNCTION__);
} else {
buf[4] = 0;
dbg("%s - stop bits = 1", __FUNCTION__);
}
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) {
buf[5] = 1;
dbg("%s - parity = odd", __FUNCTION__);
} else {
buf[5] = 2;
dbg("%s - parity = even", __FUNCTION__);
}
} else {
buf[5] = 0;
dbg("%s - parity = none", __FUNCTION__);
}
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) {
__u16 index;
if (priv->type == HX)
index = 0x61;
else
index = 0x41;
i = usb_control_msg(serial->dev,
usb_sndctrlpipe(serial->dev, 0),
VENDOR_WRITE_REQUEST,
VENDOR_WRITE_REQUEST_TYPE,
0x0, index, NULL, 0, 100);
dbg("0x40:0x1:0x0:0x%x %d", index, i);
}
kfree(buf);
}
static int pl2303_open(struct usb_serial_port *port, struct file *filp)
{
struct termios tmp_termios;
struct usb_serial *serial = port->serial;
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned char *buf;
int result;
dbg("%s - port %d", __FUNCTION__, port->number);
if (priv->type != HX) {
usb_clear_halt(serial->dev, port->write_urb->pipe);
usb_clear_halt(serial->dev, port->read_urb->pipe);
}
buf = kmalloc(10, GFP_KERNEL);
if (buf==NULL)
return -ENOMEM;
#define FISH(a,b,c,d) \
result=usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev,0), \
b, a, c, d, buf, 1, 100); \
dbg("0x%x:0x%x:0x%x:0x%x %d - %x",a,b,c,d,result,buf[0]);
#define SOUP(a,b,c,d) \
result=usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev,0), \
b, a, c, d, NULL, 0, 100); \
dbg("0x%x:0x%x:0x%x:0x%x %d",a,b,c,d,result);
FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0x0404, 0);
FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8383, 0);
FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0x0404, 1);
FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8383, 0);
SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0, 1);
SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 1, 0);
if (priv->type == HX) {
/* HX chip */
SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 2, 0x44);
/* reset upstream data pipes */
SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 8, 0);
SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 9, 0);
} else {
SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 2, 0x24);
}
kfree(buf);
/* Setup termios */
if (port->tty) {
pl2303_set_termios(port, &tmp_termios);
}
//FIXME: need to assert RTS and DTR if CRTSCTS off
dbg("%s - submitting read urb", __FUNCTION__);
port->read_urb->dev = serial->dev;
result = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (result) {
dev_err(&port->dev, "%s - failed submitting read urb,"
" error %d\n", __FUNCTION__, result);
pl2303_close(port, NULL);
return -EPROTO;
}
dbg("%s - submitting interrupt urb", __FUNCTION__);
port->interrupt_in_urb->dev = serial->dev;
result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
if (result) {
dev_err(&port->dev, "%s - failed submitting interrupt urb,"
" error %d\n", __FUNCTION__, result);
pl2303_close(port, NULL);
return -EPROTO;
}
return 0;
}
static void pl2303_close(struct usb_serial_port *port, struct file *filp)
{
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
unsigned int c_cflag;
int bps;
long timeout;
wait_queue_t wait;
dbg("%s - port %d", __FUNCTION__, port->number);
/* wait for data to drain from the buffer */
spin_lock_irqsave(&priv->lock, flags);
timeout = PL2303_CLOSING_WAIT;
init_waitqueue_entry(&wait, current);
add_wait_queue(&port->tty->write_wait, &wait);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
if (pl2303_buf_data_avail(priv->buf) == 0 ||
timeout == 0 || signal_pending(current) ||
!usb_get_intfdata(port->serial->interface)) /* disconnect */
break;
spin_unlock_irqrestore(&priv->lock, flags);
timeout = schedule_timeout(timeout);
spin_lock_irqsave(&priv->lock, flags);
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&port->tty->write_wait, &wait);
/* clear out any remaining data in the buffer */
pl2303_buf_clear(priv->buf);
spin_unlock_irqrestore(&priv->lock, flags);
/* wait for characters to drain from the device */
/* (this is long enough for the entire 256 byte */
/* pl2303 hardware buffer to drain with no flow */
/* control for data rates of 1200 bps or more, */
/* for lower rates we should really know how much */
/* data is in the buffer to compute a delay */
/* that is not unnecessarily long) */
bps = tty_get_baud_rate(port->tty);
if (bps > 1200)
timeout = max((HZ*2560)/bps,HZ/10);
else
timeout = 2*HZ;
schedule_timeout_interruptible(timeout);
/* shutdown our urbs */
dbg("%s - shutting down urbs", __FUNCTION__);
usb_kill_urb(port->write_urb);
usb_kill_urb(port->read_urb);
usb_kill_urb(port->interrupt_in_urb);
if (port->tty) {
c_cflag = port->tty->termios->c_cflag;
if (c_cflag & HUPCL) {
/* drop DTR and RTS */
spin_lock_irqsave(&priv->lock, flags);
priv->line_control = 0;
spin_unlock_irqrestore(&priv->lock, flags);
set_control_lines(port->serial->dev, 0);
}
}
}
static int pl2303_tiocmset(struct usb_serial_port *port, struct file *file,
unsigned int set, unsigned int clear)
{
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 usb_serial_port *port, struct file *file)
{
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)", __FUNCTION__, 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", __FUNCTION__, result);
return result;
}
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 usb_serial_port *port, struct file *file,
unsigned int cmd, unsigned long arg)
{
dbg("%s (%d) cmd = 0x%04x", __FUNCTION__, port->number, cmd);
switch (cmd) {
case TIOCMIWAIT:
dbg("%s (%d) TIOCMIWAIT", __FUNCTION__, port->number);
return wait_modem_info(port, arg);
default:
dbg("%s not supported = 0x%04x", __FUNCTION__, cmd);
break;
}
return -ENOIOCTLCMD;
}
static void pl2303_break_ctl(struct usb_serial_port *port, int break_state)
{
struct usb_serial *serial = port->serial;
u16 state;
int result;
dbg("%s - port %d", __FUNCTION__, port->number);
if (break_state == 0)
state = BREAK_OFF;
else
state = BREAK_ON;
dbg("%s - turning break %s", __FUNCTION__, 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", __FUNCTION__, result);
}
static void pl2303_shutdown(struct usb_serial *serial)
{
int i;
struct pl2303_private *priv;
dbg("%s", __FUNCTION__);
for (i = 0; i < serial->num_ports; ++i) {
priv = usb_get_serial_port_data(serial->port[i]);
if (priv) {
pl2303_buf_free(priv->buf);
kfree(priv);
usb_set_serial_port_data(serial->port[i], NULL);
}
}
}
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);
unsigned long flags;
u8 status_idx = UART_STATE;
u8 length = UART_STATE + 1;
if ((le16_to_cpu(port->serial->dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
(le16_to_cpu(port->serial->dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_X65 ||
le16_to_cpu(port->serial->dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_SX1 ||
le16_to_cpu(port->serial->dev->descriptor.idProduct) == 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);
priv->line_status = data[status_idx];
spin_unlock_irqrestore(&priv->lock, flags);
wake_up_interruptible(&priv->delta_msr_wait);
}
static void pl2303_read_int_callback(struct urb *urb, struct pt_regs *regs)
{
struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
unsigned char *data = urb->transfer_buffer;
unsigned int actual_length = urb->actual_length;
int status;
dbg("%s (%d)", __FUNCTION__, port->number);
switch (urb->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", __FUNCTION__,
urb->status);
return;
default:
dbg("%s - nonzero urb status received: %d", __FUNCTION__,
urb->status);
goto exit;
}
usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
urb->actual_length, urb->transfer_buffer);
pl2303_update_line_status(port, data, actual_length);
exit:
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status)
dev_err(&urb->dev->dev,
"%s - usb_submit_urb failed with result %d\n",
__FUNCTION__, status);
}
static void pl2303_read_bulk_callback(struct urb *urb, struct pt_regs *regs)
{
struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
struct pl2303_private *priv = usb_get_serial_port_data(port);
struct tty_struct *tty;
unsigned char *data = urb->transfer_buffer;
unsigned long flags;
int i;
int result;
u8 status;
char tty_flag;
dbg("%s - port %d", __FUNCTION__, port->number);
if (urb->status) {
dbg("%s - urb->status = %d", __FUNCTION__, urb->status);
if (!port->open_count) {
dbg("%s - port is closed, exiting.", __FUNCTION__);
return;
}
if (urb->status == -EPROTO) {
/* PL2303 mysteriously fails with -EPROTO reschedule
* the read */
dbg("%s - caught -EPROTO, resubmitting the urb",
__FUNCTION__);
urb->status = 0;
urb->dev = port->serial->dev;
result = usb_submit_urb(urb, GFP_ATOMIC);
if (result)
dev_err(&urb->dev->dev, "%s - failed"
" resubmitting read urb, error %d\n",
__FUNCTION__, result);
return;
}
dbg("%s - unable to handle the error, exiting.", __FUNCTION__);
return;
}
usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
urb->actual_length, data);
/* get tty_flag from status */
tty_flag = TTY_NORMAL;
spin_lock_irqsave(&priv->lock, flags);
status = priv->line_status;
priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
spin_unlock_irqrestore(&priv->lock, flags);
wake_up_interruptible(&priv->delta_msr_wait);
/* break takes precedence over parity, */
/* which takes precedence over framing errors */
if (status & UART_BREAK_ERROR )
tty_flag = TTY_BREAK;
else if (status & UART_PARITY_ERROR)
tty_flag = TTY_PARITY;
else if (status & UART_FRAME_ERROR)
tty_flag = TTY_FRAME;
dbg("%s - tty_flag = %d", __FUNCTION__, tty_flag);
tty = port->tty;
if (tty && urb->actual_length) {
[PATCH] TTY layer buffering revamp The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 12:54:13 +08:00
tty_buffer_request_room(tty, urb->actual_length + 1);
/* overrun is special, not associated with a char */
if (status & UART_OVERRUN_ERROR)
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
[PATCH] TTY layer buffering revamp The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 12:54:13 +08:00
for (i = 0; i < urb->actual_length; ++i)
tty_insert_flip_char(tty, data[i], tty_flag);
tty_flip_buffer_push(tty);
}
/* Schedule the next read _if_ we are still open */
if (port->open_count) {
urb->dev = port->serial->dev;
result = usb_submit_urb(urb, GFP_ATOMIC);
if (result)
dev_err(&urb->dev->dev, "%s - failed resubmitting"
" read urb, error %d\n", __FUNCTION__, result);
}
return;
}
static void pl2303_write_bulk_callback(struct urb *urb, struct pt_regs *regs)
{
struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
struct pl2303_private *priv = usb_get_serial_port_data(port);
int result;
dbg("%s - port %d", __FUNCTION__, port->number);
switch (urb->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", __FUNCTION__,
urb->status);
priv->write_urb_in_use = 0;
return;
default:
/* error in the urb, so we have to resubmit it */
dbg("%s - Overflow in write", __FUNCTION__);
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__,
urb->status);
port->write_urb->transfer_buffer_length = 1;
port->write_urb->dev = port->serial->dev;
result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
if (result)
dev_err(&urb->dev->dev, "%s - failed resubmitting write"
" urb, error %d\n", __FUNCTION__, result);
else
return;
}
priv->write_urb_in_use = 0;
/* send any buffered data */
pl2303_send(port);
}
/*
* pl2303_buf_alloc
*
* Allocate a circular buffer and all associated memory.
*/
static struct pl2303_buf *pl2303_buf_alloc(unsigned int size)
{
struct pl2303_buf *pb;
if (size == 0)
return NULL;
pb = (struct pl2303_buf *)kmalloc(sizeof(struct pl2303_buf), GFP_KERNEL);
if (pb == NULL)
return NULL;
pb->buf_buf = kmalloc(size, GFP_KERNEL);
if (pb->buf_buf == NULL) {
kfree(pb);
return NULL;
}
pb->buf_size = size;
pb->buf_get = pb->buf_put = pb->buf_buf;
return pb;
}
/*
* pl2303_buf_free
*
* Free the buffer and all associated memory.
*/
static void pl2303_buf_free(struct pl2303_buf *pb)
{
if (pb) {
kfree(pb->buf_buf);
kfree(pb);
}
}
/*
* pl2303_buf_clear
*
* Clear out all data in the circular buffer.
*/
static void pl2303_buf_clear(struct pl2303_buf *pb)
{
if (pb != NULL)
pb->buf_get = pb->buf_put;
/* equivalent to a get of all data available */
}
/*
* pl2303_buf_data_avail
*
* Return the number of bytes of data available in the circular
* buffer.
*/
static unsigned int pl2303_buf_data_avail(struct pl2303_buf *pb)
{
if (pb == NULL)
return 0;
return ((pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size);
}
/*
* pl2303_buf_space_avail
*
* Return the number of bytes of space available in the circular
* buffer.
*/
static unsigned int pl2303_buf_space_avail(struct pl2303_buf *pb)
{
if (pb == NULL)
return 0;
return ((pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size);
}
/*
* pl2303_buf_put
*
* Copy data data from a user buffer and put it into the circular buffer.
* Restrict to the amount of space available.
*
* Return the number of bytes copied.
*/
static unsigned int pl2303_buf_put(struct pl2303_buf *pb, const char *buf,
unsigned int count)
{
unsigned int len;
if (pb == NULL)
return 0;
len = pl2303_buf_space_avail(pb);
if (count > len)
count = len;
if (count == 0)
return 0;
len = pb->buf_buf + pb->buf_size - pb->buf_put;
if (count > len) {
memcpy(pb->buf_put, buf, len);
memcpy(pb->buf_buf, buf+len, count - len);
pb->buf_put = pb->buf_buf + count - len;
} else {
memcpy(pb->buf_put, buf, count);
if (count < len)
pb->buf_put += count;
else /* count == len */
pb->buf_put = pb->buf_buf;
}
return count;
}
/*
* pl2303_buf_get
*
* Get data from the circular buffer and copy to the given buffer.
* Restrict to the amount of data available.
*
* Return the number of bytes copied.
*/
static unsigned int pl2303_buf_get(struct pl2303_buf *pb, char *buf,
unsigned int count)
{
unsigned int len;
if (pb == NULL)
return 0;
len = pl2303_buf_data_avail(pb);
if (count > len)
count = len;
if (count == 0)
return 0;
len = pb->buf_buf + pb->buf_size - pb->buf_get;
if (count > len) {
memcpy(buf, pb->buf_get, len);
memcpy(buf+len, pb->buf_buf, count - len);
pb->buf_get = pb->buf_buf + count - len;
} else {
memcpy(buf, pb->buf_get, count);
if (count < len)
pb->buf_get += count;
else /* count == len */
pb->buf_get = pb->buf_buf;
}
return count;
}
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;
info(DRIVER_DESC);
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");