[PATCH] - PC300 driver for kernel 2.4 (6/6)

[Henrique Gobbi <henrique2.gobbi@cyclades.com>]

This is the part 6/6

diff -ruN linux-2.4.21-pre5.orig/drivers/net/wan/pc300_tty.c 
linux-2.4.21-pre5/drivers/net/wan/pc300_tty.c
--- linux-2.4.21-pre5.orig/drivers/net/wan/pc300_tty.c	Thu Jan  1 00:00:00 1970
+++ linux-2.4.21-pre5/drivers/net/wan/pc300_tty.c	Thu Feb 27 09:30:44 2003
@@ -0,0 +1,1122 @@
+/*
+ * pc300_tty.c	Cyclades-PC300(tm) TTY Driver.
+ *
+ * Author:	Regina Kodato <reginak@cyclades.com>
+ *
+ * Copyright:	(c) 1999-2002 Cyclades Corp.
+ *
+ *	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.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/if.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <linux/skbuff.h>
+
+/* TTY includes */
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+
+#include "pc300.h"
+
+/* defines and macros */
+/* TTY Global definitions */
+#define 
CPC_TTY_NPORTS 
8 
/* maximum number of the sync tty connections */
+#define 
CPC_TTY_MAJOR 
CYCLADES_MAJOR 

+#define CPC_TTY_MINOR_START	240	/* minor of the first PC300 interface */
+
+#define CPC_TTY_MAX_MTU	2000	
+
+/* tty interface state */
+#define 
CPC_TTY_ST_IDLE 
0
+#define CPC_TTY_ST_INIT	1	/* configured with MLPPP and up */
+#define CPC_TTY_ST_OPEN	2	/* opened by application */
+
+#define 
CPC_TTY_LOCK(card,flags)\
+ 
do {\
+ 
	spin_lock_irqsave(&card->card_lock, flags);	\
+ 
} while (0)
+
+#define CPC_TTY_UNLOCK(card,flags)	\
+ 
do {\
+ 
	spin_unlock_irqrestore(&card->card_lock, flags);	\
+ 
} while (0)
+
+//#define 
CPC_TTY_DBG(format,a...) 
printk(format,##a)
+#define 
CPC_TTY_DBG(format,a...)
+
+/* data structures */
+typedef struct _st_cpc_rx_buf {
+ 
struct _st_cpc_rx_buf	*next;
+ 
int 
	size;
+ 
unsigned char	data[1];
+} st_cpc_rx_buf;
+
+struct st_cpc_rx_list {
+ 
st_cpc_rx_buf 
*first;
+ 
st_cpc_rx_buf 
*last;
+};
+
+typedef 
struct _st_cpc_tty_area {
+ 
int 
	state;		/* state of the TTY interface */
+ 
int 
	num_open;	
+ 
unsigned int 	tty_minor;	/* minor this interface */
+ 
volatile struct st_cpc_rx_list buf_rx;	/* ptr. to reception buffer */
+ 
unsigned char*	buf_tx;		/* ptr. to transmission buffer */
+ 
pc300dev_t* 
pc300dev; 
/* ptr. to info struct in PC300 driver */
+ 
unsigned char	name[20];	/* interf. name + "-tty" */
+ 
struct tty_struct *tty;		
+ 
struct tq_struct tty_tx_task_queue; /* tx task - tx interrupt */
+ 
struct tq_struct tty_rx_task_queue; /* rx task - rx interrupt */
+ 
} st_cpc_tty_area;
+
+/* TTY data structures */
+static struct tty_struct *cpc_tty_serial_table[CPC_TTY_NPORTS];
+static struct termios *cpc_tty_serial_termios[CPC_TTY_NPORTS];
+static struct termios *cpc_tty_serial_termios_locked[CPC_TTY_NPORTS];
+static struct tty_driver serial_drv, callout_drv;
+
+/* local variables */
+st_cpc_tty_area 
cpc_tty_area[CPC_TTY_NPORTS];
+
+int cpc_tty_cnt=0;	/* number of intrfaces configured with MLPPP */
+int cpc_tty_refcount;
+int cpc_tty_unreg_flag = 0;
+
+/* TTY functions prototype */
+static int cpc_tty_open(struct tty_struct *tty, struct file *flip);
+static void cpc_tty_close(struct tty_struct *tty, struct file *flip);
+static int cpc_tty_write(struct tty_struct *tty, int from_user,
+ 
			const unsigned char *buf, int count);
+static int cpc_tty_write_room(struct tty_struct *tty);
+static int cpc_tty_chars_in_buffer(struct tty_struct *tty);
+static int cpc_tty_ioctl(struct tty_struct *tty, struct file *file,
+ 
			unsigned int cmd, unsigned long arg);
+static void cpc_tty_flush_buffer(struct tty_struct *tty);
+static void cpc_tty_hangup(struct tty_struct *tty);
+static void cpc_tty_rx_task(void *data);
+static void cpc_tty_tx_task(void *data);
+static int cpc_tty_send_to_card(pc300dev_t *dev,void *buf, int len);
+static void cpc_tty_trace(pc300dev_t *dev, char* buf, int len, char rxtx);
+static void cpc_tty_dtr_off(pc300dev_t *pc300dev);
+static void cpc_tty_dtr_on(pc300dev_t *pc300dev);
+
+/* functions called by PC300 driver */
+void cpc_tty_init(pc300dev_t *dev);
+void cpc_tty_unregister_service(pc300dev_t *pc300dev);
+void cpc_tty_receive(pc300dev_t *pc300dev);
+void cpc_tty_trigger_poll(pc300dev_t *pc300dev);
+void cpc_tty_reset_var(void);
+
+/*
+ * PC300 TTY clear DTR signal
+ */
+static void cpc_tty_dtr_off(pc300dev_t *pc300dev)
+{
+ 
pc300ch_t *pc300chan = (pc300ch_t *)pc300dev->chan;
+ 
pc300_t *card = (pc300_t *) pc300chan->card;
+ 
int ch = pc300chan->channel;
+ 
unsigned long flags;
+
+ 
CPC_TTY_DBG("%s-tty: Clear signal DTR\n",
+ 
	((struct net_device*)(pc300dev->hdlc))->name);
+ 
CPC_TTY_LOCK(card, flags);
+ 
cpc_writeb(card->hw.scabase + M_REG(CTL,ch),
+ 
	cpc_readb(card->hw.scabase+M_REG(CTL,ch))& CTL_DTR);
+ 
CPC_TTY_UNLOCK(card,flags);
+}
+
+/*
+ * PC300 TTY set DTR signal to ON
+ */
+static void cpc_tty_dtr_on(pc300dev_t *pc300dev)
+{
+ 
pc300ch_t *pc300chan = (pc300ch_t *)pc300dev->chan;
+ 
pc300_t *card = (pc300_t *) pc300chan->card;
+ 
int ch = pc300chan->channel;
+ 
unsigned long flags;
+
+ 
CPC_TTY_DBG("%s-tty: Set signal DTR\n",
+ 
	((struct net_device*)(pc300dev->hdlc))->name);
+ 
CPC_TTY_LOCK(card, flags);
+ 
cpc_writeb(card->hw.scabase + M_REG(CTL,ch),
+ 
	cpc_readb(card->hw.scabase+M_REG(CTL,ch))& ~CTL_DTR);
+ 
CPC_TTY_UNLOCK(card,flags);
+}
+
+/*
+ * PC300 TTY initialization routine
+ *
+ * This routine is called by the PC300 driver during board configuration
+ * (ioctl=SIOCSP300CONF). At this point the adapter is completely
+ * initialized.
+ * o verify kernel version (only 2.4.x)
+ * o register TTY driver
+ * o init cpc_tty_area struct
+ */
+void cpc_tty_init(pc300dev_t *pc300dev)
+{
+ 
int port, aux;
+ 
st_cpc_tty_area * cpc_tty;
+
+ 
if (LINUX_VERSION_CODE < KERNEL_VERSION(2,4,0)) {
+ 
	printk("%s-tty: Error: TTY driver is supported on 2.4.X kernel!\n",
+ 
		((struct net_device*)(pc300dev->hdlc))->name);
+ 
	return;
+ 
}
+ 

+ 
/* hdlcX - X=interface number */
+ 
port = ((struct net_device*)(pc300dev->hdlc))->name[4] - '0';
+ 
if (port >= CPC_TTY_NPORTS) {
+ 
	printk("%s-tty: invalid interface selected (0-%i): %i",
+ 
		((struct net_device*)(pc300dev->hdlc))->name,
+ 
		CPC_TTY_NPORTS-1,port);
+ 
	return;
+ 
}
+
+ 
if (cpc_tty_cnt == 0) { /* first TTY connection -> register driver */
+ 
	CPC_TTY_DBG("%s-tty: driver init, major:%i, minor range:%i=%i\n",
+ 
		((struct net_device*)(pc300dev->hdlc))->name,
+ 
		CPC_TTY_MAJOR, CPC_TTY_MINOR_START,
+ 
		CPC_TTY_MINOR_START+CPC_TTY_NPORTS);
+ 
	/* initialize tty driver struct */
+ 
	memset(&serial_drv,0,sizeof(struct tty_driver));
+ 
	serial_drv.magic = TTY_DRIVER_MAGIC;
+ 
	serial_drv.driver_name = "pc300_tty";
+ 
	serial_drv.name = "ttyCP";
+ 
	serial_drv.major = CPC_TTY_MAJOR;
+ 
	serial_drv.minor_start = CPC_TTY_MINOR_START;
+ 
	serial_drv.num = CPC_TTY_NPORTS;
+ 
	serial_drv.type = TTY_DRIVER_TYPE_SERIAL;
+ 
	serial_drv.subtype = SERIAL_TYPE_NORMAL;
+
+ 
	serial_drv.init_termios = tty_std_termios;
+ 
	serial_drv.init_termios.c_cflag = B9600|CS8|CREAD|HUPCL|CLOCAL;
+ 
	serial_drv.flags = TTY_DRIVER_REAL_RAW;
+ 
	serial_drv.refcount = &cpc_tty_refcount;
+
+ 
	/* tty data structures */
+ 
	serial_drv.table = cpc_tty_serial_table;
+ 
	serial_drv.termios = cpc_tty_serial_termios;
+ 
	serial_drv.termios_locked = cpc_tty_serial_termios_locked;
+
+ 
	/* interface routines from the upper tty layer to the tty driver */
+ 
	serial_drv.open = cpc_tty_open;
+ 
	serial_drv.close = cpc_tty_close;
+ 
	serial_drv.write = cpc_tty_write;
+ 
	serial_drv.write_room = cpc_tty_write_room;
+ 
	serial_drv.chars_in_buffer = cpc_tty_chars_in_buffer;
+ 
	serial_drv.ioctl = cpc_tty_ioctl;
+ 
	serial_drv.flush_buffer = cpc_tty_flush_buffer;
+ 
	serial_drv.hangup = cpc_tty_hangup;
+
+ 
	/* the callout device is just like normal device except for major */
+ 
    	/* number and the subtype code */
+ 
	callout_drv = serial_drv;
+ 
	callout_drv.name = "cucp";
+ 
	callout_drv.major = CPC_TTY_MAJOR + 1;
+ 
	callout_drv.subtype = SERIAL_TYPE_CALLOUT;
+ 
	callout_drv.read_proc = 0;
+ 
	callout_drv.proc_entry = 0;
+ 
	
+ 
	/* register the TTY driver */
+ 
	if (tty_register_driver(&serial_drv)) {
+ 
		printk("%s-tty: Failed to register serial driver! ",
+ 
			((struct net_device*)(pc300dev->hdlc))->name);
+ 
	   	return;
+ 
	}
+
+ 
	if (tty_register_driver(&callout_drv)) {
+ 
		CPC_TTY_DBG("%s-tty: Failed to register callout driver! ",
+ 
			((struct net_device*)(pc300dev->hdlc))->name);
+ 
		return;
+ 
	}
+ 
	memset((void *)cpc_tty_area, 0,
+ 
							sizeof(st_cpc_tty_area) * CPC_TTY_NPORTS);
+ 
}
+
+ 
cpc_tty = &cpc_tty_area[port];
+ 

+ 
if (cpc_tty->state != CPC_TTY_ST_IDLE) {
+ 
	CPC_TTY_DBG("%s-tty: TTY port %i, already in use.\n",
+ 
				((struct net_device*)(pc300dev->hdlc))->name,port);
+ 
	return;
+ 
}
+
+ 
cpc_tty_cnt++;
+ 
cpc_tty->state = CPC_TTY_ST_INIT;
+ 
cpc_tty->num_open= 0;
+ 
cpc_tty->tty_minor = port + CPC_TTY_MINOR_START;
+ 
cpc_tty->pc300dev = pc300dev;
+ 

+ 
cpc_tty->tty_tx_task_queue.routine = cpc_tty_tx_task;
+ 
cpc_tty->tty_tx_task_queue.data = (void *)cpc_tty;
+ 

+ 
cpc_tty->tty_rx_task_queue.routine = cpc_tty_rx_task;
+ 
cpc_tty->tty_rx_task_queue.data = (void *) port;
+ 

+ 
cpc_tty->buf_rx.first = cpc_tty->buf_rx.last = 0;
+
+ 
pc300dev->cpc_tty = (void *)cpc_tty;
+ 

+ 
aux = strlen(((struct net_device*)(pc300dev->hdlc))->name);
+ 
memcpy(cpc_tty->name,((struct net_device*)(pc300dev->hdlc))->name,aux);
+ 
memcpy(&cpc_tty->name[aux], "-tty", 5);
+ 

+ 
cpc_open((struct net_device *)pc300dev->hdlc);
+ 
cpc_tty_dtr_off(pc300dev);
+
+ 
CPC_TTY_DBG("%s: Initializing TTY Sync Driver, tty major#%d minor#%i\n",
+ 
		cpc_tty->name,CPC_TTY_MAJOR,cpc_tty->tty_minor);
+ 
return;
+}
+
+/*
+ * PC300 TTY OPEN routine
+ *
+ * This routine is called by the tty driver to open the interface
+ * o verify minor
+ * o allocate buffer to Rx and Tx
+ */
+static int cpc_tty_open(struct tty_struct *tty, struct file *flip)
+{
+ 
int port ;
+ 
st_cpc_tty_area *cpc_tty;
+
+ 
if (!tty) {
+ 
	return -ENODEV;
+ 
}
+
+ 
port = MINOR(tty->device) - tty->driver.minor_start;
+
+ 
if ((port < 0) || (port >= CPC_TTY_NPORTS)){
+ 
	CPC_TTY_DBG("pc300_tty: open invalid minor %i\n",MINOR(tty->device));
+ 
	return -ENODEV;
+ 
}
+
+ 
cpc_tty = &cpc_tty_area[port];
+ 

+ 
if (cpc_tty->state == CPC_TTY_ST_IDLE){
+ 
	CPC_TTY_DBG("%s: open - invalid interface, minor=%i\n",
+ 
				cpc_tty->name, MINOR(tty->device));
+ 
	return -ENODEV;
+ 
}
+
+ 
if (cpc_tty->num_open == 0) { /* first open of this tty */
+ 
	if (!cpc_tty_area[port].buf_tx){
+ 
		cpc_tty_area[port].buf_tx = kmalloc(CPC_TTY_MAX_MTU,GFP_KERNEL);
+ 
		if (cpc_tty_area[port].buf_tx == 0){
+ 
			CPC_TTY_DBG("%s: error in memory allocation\n",cpc_tty->name);
+ 
			return -ENOMEM;
+ 
		}
+ 
	}
+
+ 
	if (cpc_tty_area[port].buf_rx.first) {
+ 
		unsigned char * aux;
+ 
		while (cpc_tty_area[port].buf_rx.first) {
+ 
			aux = (unsigned char *)cpc_tty_area[port].buf_rx.first;
+ 
			cpc_tty_area[port].buf_rx.first = cpc_tty_area[port].buf_rx.first->next;
+ 
			kfree(aux);
+ 
		}
+ 
		cpc_tty_area[port].buf_rx.first = NULL;
+ 
		cpc_tty_area[port].buf_rx.last = NULL;
+ 
	}
+
+ 
	cpc_tty_area[port].state = CPC_TTY_ST_OPEN;
+ 
	cpc_tty_area[port].tty = tty;
+ 
	tty->driver_data = &cpc_tty_area[port];
+
+ 
	cpc_tty_dtr_on(cpc_tty->pc300dev);
+ 
}
+
+ 
cpc_tty->num_open++;
+
+ 
CPC_TTY_DBG("%s: opening TTY driver\n", cpc_tty->name);
+ 

+ 
/* avisar driver PC300 */
+ 
return 0;
+}
+
+/*
+ * PC300 TTY CLOSE routine
+ *
+ * This routine is called by the tty driver to close the interface
+ * o call close channel in PC300 driver (cpc_closech)
+ * o free Rx and Tx buffers
+ */
+
+static void cpc_tty_close(struct tty_struct *tty, struct file *flip)
+{
+ 
st_cpc_tty_area    *cpc_tty;
+ 
unsigned long flags;
+ 
int res;
+
+ 
if (!tty || !tty->driver_data ) {
+ 
	CPC_TTY_DBG("hdlx-tty: no TTY in close \n");
+ 
	return;
+ 
}
+
+ 
cpc_tty = (st_cpc_tty_area *) tty->driver_data;
+
+ 
if ((cpc_tty->tty != tty)|| (cpc_tty->state != CPC_TTY_ST_OPEN)) {
+ 
	CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
+ 
	return;
+ 
}
+   	
+ 
if (!cpc_tty->num_open) {
+ 
	CPC_TTY_DBG("%s: TTY is closed\n",cpc_tty->name);
+ 
	return;
+ 
}
+
+ 
if (--cpc_tty->num_open > 0) {
+ 
	CPC_TTY_DBG("%s: TTY closed\n",cpc_tty->name);
+ 
	return;
+ 
}
+
+ 
cpc_tty_dtr_off(cpc_tty->pc300dev);
+
+ 
CPC_TTY_LOCK(cpc_tty->pc300dev->chan->card, flags);  /* lock irq */
+ 
cpc_tty->tty = NULL;
+ 
cpc_tty->state = CPC_TTY_ST_INIT;
+ 
CPC_TTY_UNLOCK(cpc_tty->pc300dev->chan->card, flags); /* unlock irq */
+ 

+ 
if (cpc_tty->buf_rx.first) {
+ 
	unsigned char * aux;
+ 
	while (cpc_tty->buf_rx.first) {
+ 
		aux = (unsigned char *)cpc_tty->buf_rx.first;
+ 
		cpc_tty->buf_rx.first = cpc_tty->buf_rx.first->next;
+ 
		kfree(aux);
+ 
	}
+ 
	cpc_tty->buf_rx.first = NULL;
+ 
	cpc_tty->buf_rx.last = NULL;
+ 
}
+ 

+ 
if (cpc_tty->buf_tx) {
+ 
	kfree(cpc_tty->buf_tx);
+ 
	cpc_tty->buf_tx = NULL;
+ 
}
+
+ 
CPC_TTY_DBG("%s: TTY closed\n",cpc_tty->name);
+ 

+ 
if (!cpc_tty_refcount && cpc_tty_unreg_flag) {
+ 
	cpc_tty_unreg_flag = 0;
+ 
	CPC_TTY_DBG("%s: unregister the tty driver\n", cpc_tty->name);
+ 
	if ((res=tty_unregister_driver(&serial_drv))) {
+ 
		CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
+ 
						cpc_tty->name,res);
+ 
	}
+ 
	if ((res=tty_unregister_driver(&callout_drv))) {
+ 
		CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
+ 
						cpc_tty->name,res);
+ 
	}
+ 
}
+ 
return;
+}
+
+/*
+ * PC300 TTY WRITE routine
+ *
+ * This routine is called by the tty driver to write a series of characters
+ * to the tty device. The characters may come from user or kernel space.
+ * o verify the DCD signal
+ * o send characters to board and start the transmission
+ */
+static int cpc_tty_write(struct tty_struct *tty, int from_user,
+ 
		const unsigned char *buf, int count)
+{
+ 
st_cpc_tty_area    *cpc_tty;
+ 
pc300ch_t *pc300chan;
+ 
pc300_t *card;
+ 
int ch;
+ 
unsigned long flags;
+ 
struct net_device_stats *stats;
+
+ 
if (!tty || !tty->driver_data ) {
+ 
	CPC_TTY_DBG("hdlcX-tty: no TTY in write\n");
+ 
	return -ENODEV;
+ 
}
+
+ 
cpc_tty = (st_cpc_tty_area *) tty->driver_data;
+
+ 
if ((cpc_tty->tty != tty) ||  (cpc_tty->state != CPC_TTY_ST_OPEN)) {
+ 
	CPC_TTY_DBG("%s: TTY is not opened\n", cpc_tty->name);
+ 
	return -ENODEV;
+ 
}
+
+ 
if (count > CPC_TTY_MAX_MTU) {
+ 
	CPC_TTY_DBG("%s: count is invalid\n",cpc_tty->name);
+ 
	return -EINVAL;        /* frame too big */
+ 
}
+
+ 
CPC_TTY_DBG("%s: cpc_tty_write %s data len=%i\n",cpc_tty->name,
+ 
	(from_user)?"from user" : "from kernel",count);
+ 

+ 
pc300chan = (pc300ch_t *)((pc300dev_t*)cpc_tty->pc300dev)->chan;
+ 
stats = &((pc300dev_t*)cpc_tty->pc300dev)->hdlc->stats;
+ 
card = (pc300_t *) pc300chan->card;
+ 
ch = pc300chan->channel;
+
+ 
/* verify DCD signal*/
+ 
if (cpc_readb(card->hw.scabase + M_REG(ST3,ch)) & ST3_DCD) {
+ 
	/* DCD is OFF */
+ 
	CPC_TTY_DBG("%s : DCD is OFF\n", cpc_tty->name);
+ 
	stats->tx_errors++;
+ 
	stats->tx_carrier_errors++;
+ 
	CPC_TTY_LOCK(card, flags);
+ 
	cpc_writeb(card->hw.scabase + M_REG(CMD, ch), CMD_TX_BUF_CLR);
+ 
	
+ 
	if (card->hw.type == PC300_TE) {
+ 
		cpc_writeb(card->hw.falcbase + card->hw.cpld_reg2,
+ 
			cpc_readb(card->hw.falcbase + card->hw.cpld_reg2) &
+ 
			~(CPLD_REG2_FALC_LED1 << (2 *ch)));
+ 
	}
+
+ 
	CPC_TTY_UNLOCK(card, flags);
+
+ 
	return -EINVAL;
+ 
}
+
+ 
if (from_user) {
+ 
	unsigned char *buf_tmp;
+
+ 
	buf_tmp = cpc_tty->buf_tx;
+ 
	if (copy_from_user(buf_tmp, buf, count)) {
+ 
		/* failed to copy from user */
+ 
		CPC_TTY_DBG("%s: error in copy from user\n",cpc_tty->name);
+ 
		return -EINVAL;
+ 
	}
+
+ 
	if (cpc_tty_send_to_card(cpc_tty->pc300dev, (void*) buf_tmp,count)) {
+ 
		/* failed to send */
+ 
		CPC_TTY_DBG("%s: transmission error\n",cpc_tty->name);
+ 
		return 0;
+ 
	}
+ 
} else {
+ 
	if (cpc_tty_send_to_card(cpc_tty->pc300dev, (void*)buf, count)) {
+ 
	   /* failed to send */
+ 
	   CPC_TTY_DBG("%s: trasmition error\n", cpc_tty->name);
+ 
	   return 0;
+ 
	}
+ 
}
+ 
return count;
+}
+
+/*
+ * PC300 TTY Write Room routine
+ *
+ * This routine returns the numbers of characteres the tty driver will 
accept
+ * for queuing to be written.
+ * o return MTU
+ */
+static int cpc_tty_write_room(struct tty_struct *tty)
+{
+ 
st_cpc_tty_area    *cpc_tty;
+
+ 
if (!tty || !tty->driver_data ) {
+ 
	CPC_TTY_DBG("hdlcX-tty: no TTY to write room\n");
+ 
	return -ENODEV;
+ 
}
+
+ 
cpc_tty = (st_cpc_tty_area *) tty->driver_data;
+
+ 
if ((cpc_tty->tty != tty) ||  (cpc_tty->state != CPC_TTY_ST_OPEN)) {
+ 
	CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
+ 
	return -ENODEV;
+ 
}
+   	
+ 
CPC_TTY_DBG("%s: write room\n",cpc_tty->name);
+ 

+ 
return CPC_TTY_MAX_MTU;
+}
+
+/*
+ * PC300 TTY chars in buffer routine
+ *
+ * This routine returns the chars number in the transmission buffer
+ * o returns 0
+ */
+static int cpc_tty_chars_in_buffer(struct tty_struct *tty)
+{
+ 
st_cpc_tty_area    *cpc_tty;
+
+ 
if (!tty || !tty->driver_data ) {
+ 
	CPC_TTY_DBG("hdlcX-tty: no TTY to chars in buffer\n");
+ 
	return -ENODEV;
+ 
}
+
+ 
cpc_tty = (st_cpc_tty_area *) tty->driver_data;
+
+ 
if ((cpc_tty->tty != tty) || (cpc_tty->state != CPC_TTY_ST_OPEN)) {
+ 
	CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
+ 
	return -ENODEV;
+ 
}
+
+ 
return(0);
+}
+
+/*
+ * PC300 TTY IOCTL routine
+ *
+ * This routine treats TIOCMBIS (set DTR signal) and TIOCMBIC (clear DTR
+ * signal)IOCTL commands.
+ */
+static int cpc_tty_ioctl(struct tty_struct *tty, struct file *file,
+ 
	unsigned int cmd, unsigned long arg)
+
+{
+ 
st_cpc_tty_area    *cpc_tty;
+
+ 
if (!tty || !tty->driver_data ) {
+ 
    	CPC_TTY_DBG("hdlcX-tty: no TTY to chars in buffer\n");	
+ 
	return -ENODEV;
+ 
}
+
+ 
cpc_tty = (st_cpc_tty_area *) tty->driver_data;
+
+ 
if ((cpc_tty->tty != tty) ||  (cpc_tty->state != CPC_TTY_ST_OPEN)) {
+ 
	CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
+ 
	return -ENODEV;
+ 
}
+
+ 
CPC_TTY_DBG("%s: IOCTL cmd %x\n",cpc_tty->name,cmd);
+ 

+ 
switch (cmd) {
+ 
	case TIOCMBIS :    /* set DTR */
+ 
		cpc_tty_dtr_on(cpc_tty->pc300dev);
+ 
		break;
+
+ 
	case TIOCMBIC:     /* clear DTR */
+ 
		cpc_tty_dtr_off(cpc_tty->pc300dev);
+ 
		break;
+ 
	default :
+ 
		return -ENOIOCTLCMD;
+ 
}
+ 
return 0;
+}
+
+/*
+ * PC300 TTY Flush Buffer routine
+ *
+ * This routine resets the transmission buffer
+ */
+static void cpc_tty_flush_buffer(struct tty_struct *tty)
+{
+ 
st_cpc_tty_area    *cpc_tty;
+ 

+ 
if (!tty || !tty->driver_data ) {
+ 
    	CPC_TTY_DBG("hdlcX-tty: no TTY to flush buffer\n");	
+ 
	return;
+ 
}
+
+ 
cpc_tty = (st_cpc_tty_area *) tty->driver_data;
+
+ 
if ((cpc_tty->tty != tty) ||  (cpc_tty->state != CPC_TTY_ST_OPEN)) {
+ 
	CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
+ 
	return;
+ 
}
+
+ 
CPC_TTY_DBG("%s: call wake_up_interruptible\n",cpc_tty->name);
+ 

+ 
wake_up_interruptible(&tty->write_wait);
+
+ 
if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup){
+ 
	CPC_TTY_DBG("%s: call line disc. wake up\n",cpc_tty->name);
+ 
	tty->ldisc.write_wakeup(tty);
+ 
}
+
+ 
return;
+}
+
+/*
+ * PC300 TTY Hangup routine
+ *
+ * This routine is called by the tty driver to hangup the interface
+ * o clear DTR signal
+ */
+
+static void cpc_tty_hangup(struct tty_struct *tty)
+{
+ 
st_cpc_tty_area    *cpc_tty;
+ 
int res;
+
+ 
if (!tty || !tty->driver_data ) {
+ 
	CPC_TTY_DBG("hdlcX-tty: no TTY to hangup\n");	
+ 
	return ;
+ 
}
+
+ 
cpc_tty = (st_cpc_tty_area *) tty->driver_data;
+
+ 
if ((cpc_tty->tty != tty) || (cpc_tty->state != CPC_TTY_ST_OPEN)) {
+ 
	CPC_TTY_DBG("%s: TTY is not opened\n",cpc_tty->name);
+ 
	return ;
+ 
}
+ 
if (!cpc_tty_refcount && cpc_tty_unreg_flag) {
+ 
	cpc_tty_unreg_flag = 0;
+ 
	CPC_TTY_DBG("%s: unregister the tty driver\n", cpc_tty->name);
+ 
	if ((res=tty_unregister_driver(&serial_drv))) {
+ 
		CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
+ 
						cpc_tty->name,res);
+ 
	}
+ 
	if ((res=tty_unregister_driver(&callout_drv))) {
+ 
		CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
+ 
						cpc_tty->name,res);
+ 
	}
+ 
}
+ 
cpc_tty_dtr_off(cpc_tty->pc300dev);
+}
+
+/*
+ * PC300 TTY RX task routine
+ * This routine treats RX task
+ * o verify read buffer
+ * o call the line disc. read
+ * o free memory
+ */
+static void cpc_tty_rx_task(void * data)
+{
+ 
int port, i, j;
+ 
st_cpc_tty_area *cpc_tty;
+ 
volatile st_cpc_rx_buf * buf;
+ 
char flags=0,flg_rx=1;
+
+ 
if (cpc_tty_cnt == 0) return;
+
+ 
for (i=0; (i < 4) && flg_rx ; i++) {
+ 
	flg_rx = 0;
+ 
	port = (int) data;
+ 
	for (j=0; j < CPC_TTY_NPORTS; j++) {
+ 
		cpc_tty = &cpc_tty_area[port];
+ 
	
+ 
		if ((buf=cpc_tty->buf_rx.first) != 0) {
+ 
														
+ 
			if (cpc_tty->tty && (cpc_tty->tty->ldisc.receive_buf)) {
+ 
				CPC_TTY_DBG("%s: call line disc. receive_buf\n",cpc_tty->name);
+ 
				cpc_tty->tty->ldisc.receive_buf(cpc_tty->tty, buf->data,
+ 
												&flags, buf->size);
+ 
			}	
+ 
			cpc_tty->buf_rx.first = cpc_tty->buf_rx.first->next;
+ 
			kfree((unsigned char *)buf);
+ 
			buf = cpc_tty->buf_rx.first;
+ 
			flg_rx = 1;
+ 
		}
+ 
		if (++port == CPC_TTY_NPORTS) port = 0;
+ 
	}
+ 
}
+}
+
+/*
+ * PC300 TTY RX task routine
+ *
+ * This routine treats RX interrupt.
+ * o read all frames in card
+ * o verify the frame size
+ * o read the frame in rx buffer
+ */
+static void cpc_tty_rx_disc_frame(pc300ch_t *pc300chan)
+{
+ 
volatile pcsca_bd_t * ptdescr;
+ 
volatile unsigned char status;
+ 
pc300_t *card = (pc300_t *)pc300chan->card;
+ 
int ch = pc300chan->channel;
+
+ 
/* dma buf read */
+ 
ptdescr = (pcsca_bd_t *)(card->hw.rambase +
+ 
			RX_BD_ADDR(ch, pc300chan->rx_first_bd));
+ 
while (pc300chan->rx_first_bd != pc300chan->rx_last_bd) {
+ 
	status = cpc_readb(&ptdescr->status);
+ 
	cpc_writeb(&ptdescr->status, 0);
+ 
	cpc_writeb(&ptdescr->len, 0);
+ 
	pc300chan->rx_first_bd = (pc300chan->rx_first_bd + 1) &
+ 
				(N_DMA_RX_BUF - 1);
+ 
	if (status & DST_EOM) {
+ 
		break; /* end of message */
+ 
	}
+ 
	ptdescr = (pcsca_bd_t *)(card->hw.rambase + cpc_readl(&ptdescr->next));
+ 
}
+}
+
+void cpc_tty_receive(pc300dev_t *pc300dev)
+{
+ 
st_cpc_tty_area    *cpc_tty;
+ 
pc300ch_t *pc300chan = (pc300ch_t *)pc300dev->chan;
+ 
pc300_t *card = (pc300_t *)pc300chan->card;
+ 
int ch = pc300chan->channel;
+ 
volatile pcsca_bd_t * ptdescr;
+ 
struct net_device_stats *stats = &pc300dev->hdlc->stats;
+ 
int rx_len, rx_aux;
+ 
volatile unsigned char status;
+ 
unsigned short first_bd = pc300chan->rx_first_bd;
+ 
st_cpc_rx_buf 
*new;
+ 
unsigned char dsr_rx;
+
+ 
if (pc300dev->cpc_tty == NULL) {
+ 
	return;
+ 
}
+
+ 
dsr_rx = cpc_readb(card->hw.scabase + DSR_RX(ch));
+
+ 
cpc_tty = (st_cpc_tty_area *)pc300dev->cpc_tty;
+
+ 
while (1) {
+ 
	rx_len = 0;
+ 
	ptdescr = (pcsca_bd_t *)(card->hw.rambase + RX_BD_ADDR(ch, first_bd));
+ 
	while ((status = cpc_readb(&ptdescr->status)) & DST_OSB) {
+ 
		rx_len += cpc_readw(&ptdescr->len);
+ 
		first_bd = (first_bd + 1) & (N_DMA_RX_BUF - 1);
+ 
		if (status & DST_EOM) {
+ 
			break;
+ 
		}
+ 
		ptdescr=(pcsca_bd_t*)(card->hw.rambase+cpc_readl(&ptdescr->next));
+ 
	}
+ 
		
+ 
	if (!rx_len) {
+ 
		if (dsr_rx & DSR_BOF) {
+ 
			/* update EDA */
+ 
			cpc_writel(card->hw.scabase + DRX_REG(EDAL, ch),
+ 
					RX_BD_ADDR(ch, pc300chan->rx_last_bd));
+ 
		}
+ 
		return;
+ 
	}
+ 
	
+ 
	if (rx_len > CPC_TTY_MAX_MTU) {
+ 
		/* Free RX descriptors */
+ 
		CPC_TTY_DBG("%s: frame size is invalid.\n",cpc_tty->name);
+ 
		stats->rx_errors++;
+ 
		stats->rx_frame_errors++;
+ 
		cpc_tty_rx_disc_frame(pc300chan);
+ 
		continue;
+ 
	}
+ 
	
+ 
	new = (st_cpc_rx_buf *) kmalloc(rx_len + sizeof(st_cpc_rx_buf), GFP_ATOMIC);
+ 
	if (new == 0) {
+ 
		cpc_tty_rx_disc_frame(pc300chan);
+ 
		continue;
+ 
	}
+ 
	
+ 
	/* dma buf read */
+ 
	ptdescr = (pcsca_bd_t *)(card->hw.rambase +
+ 
			RX_BD_ADDR(ch, pc300chan->rx_first_bd));
+
+ 
	rx_len = 0;	/* counter frame size */
+ 
	
+ 
	while ((status = cpc_readb(&ptdescr->status)) & DST_OSB) {
+ 
		rx_aux = cpc_readw(&ptdescr->len);
+ 
		if ((status & (DST_OVR | DST_CRC | DST_RBIT |  DST_SHRT | DST_ABT))
+ 
			|| (rx_aux > BD_DEF_LEN)) {
+ 
			CPC_TTY_DBG("%s: reception error\n", cpc_tty->name);
+ 
			stats->rx_errors++;
+ 
			if (status & DST_OVR) {
+ 
				stats->rx_fifo_errors++;
+ 
			}
+ 
			if (status & DST_CRC) {
+ 
				stats->rx_crc_errors++;
+ 
			}
+ 
			if ((status & (DST_RBIT | DST_SHRT | DST_ABT)) ||
+ 
				(rx_aux > BD_DEF_LEN))	{
+ 
				stats->rx_frame_errors++;
+ 
			}
+ 
			/* discard remainig descriptors used by the bad frame */
+ 
			CPC_TTY_DBG("%s: reception error - discard descriptors",
+ 
					cpc_tty->name);
+ 
			cpc_tty_rx_disc_frame(pc300chan);
+ 
			rx_len = 0;
+ 
			kfree((unsigned char *)new);
+ 
			break; /* read next frame - while(1) */
+ 
		}
+
+ 
		if (cpc_tty->state != CPC_TTY_ST_OPEN) {
+ 
			/* Free RX descriptors */
+ 
			cpc_tty_rx_disc_frame(pc300chan);
+ 
			stats->rx_dropped++;
+ 
			rx_len = 0;
+ 
			kfree((unsigned char *)new);
+ 
			break; /* read next frame - while(1) */
+ 
		}
+
+ 
		/* read the segment of the frame */
+ 
		if (rx_aux != 0) {
+ 
			memcpy_fromio((new->data + rx_len),
+ 
				(void *)(card->hw.rambase +
+ 
				 cpc_readl(&ptdescr->ptbuf)), rx_aux);
+ 
			rx_len += rx_aux;
+ 
		}
+ 
		cpc_writeb(&ptdescr->status,0);
+ 
		cpc_writeb(&ptdescr->len, 0);
+ 
		pc300chan->rx_first_bd = (pc300chan->rx_first_bd + 1) &
+ 
				(N_DMA_RX_BUF -1);
+ 
		if (status & DST_EOM)break;
+ 
		
+ 
		ptdescr = (pcsca_bd_t *) (card->hw.rambase +
+ 
				cpc_readl(&ptdescr->next));
+ 
	}
+ 
	/* update pointer */
+ 
	pc300chan->rx_last_bd = (pc300chan->rx_first_bd - 1) &
+ 
				(N_DMA_RX_BUF - 1) ;
+ 
	if (!(dsr_rx & DSR_BOF)) {
+ 
		/* update EDA */
+ 
		cpc_writel(card->hw.scabase + DRX_REG(EDAL, ch),
+ 
				RX_BD_ADDR(ch, pc300chan->rx_last_bd));
+ 
	}
+ 
	if (rx_len != 0) {
+ 
		stats->rx_bytes += rx_len;
+ 
	
+ 
		if (pc300dev->trace_on) {
+ 
			cpc_tty_trace(pc300dev, new->data,rx_len, 'R');
+ 
		}
+ 
		new->size = rx_len;
+ 
		new->next = 0;
+ 
		if (cpc_tty->buf_rx.first == 0) {
+ 
			cpc_tty->buf_rx.first = new;
+ 
			cpc_tty->buf_rx.last = new;
+ 
		} else {
+ 
			cpc_tty->buf_rx.last->next = new;
+ 
			cpc_tty->buf_rx.last = new;
+ 
		}
+ 
		schedule_task(&(cpc_tty->tty_rx_task_queue));
+ 
		stats->rx_packets++;
+ 
	}
+ 
}
+}
+
+/*
+ * PC300 TTY TX task routine
+ *
+ * This routine treats TX interrupt.
+ * o if need call line discipline wakeup
+ * o call wake_up_interruptible
+ */
+static void cpc_tty_tx_task(void *data)
+{
+ 
st_cpc_tty_area *cpc_tty = (st_cpc_tty_area *) data;
+ 
struct tty_struct *tty;
+
+ 
CPC_TTY_DBG("%s: cpc_tty_tx_task init\n",cpc_tty->name);
+ 

+ 
if ((tty = cpc_tty->tty) == 0) {
+ 
	CPC_TTY_DBG("%s: the interface is not opened\n",cpc_tty->name);
+ 
	return;
+ 
}
+
+ 
if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup){
+ 
	CPC_TTY_DBG("%s:call line disc. wakeup\n",cpc_tty->name);
+ 
	tty->ldisc.write_wakeup (tty);
+ 
}
+
+ 
wake_up_interruptible(&tty->write_wait);
+}
+
+/*
+ * PC300 TTY send to card routine
+ *
+ * This routine send data to card.
+ * o clear descriptors
+ * o write data to DMA buffers
+ * o start the transmission
+ */
+static int cpc_tty_send_to_card(pc300dev_t *dev,void* buf, int len)
+{
+ 
pc300ch_t *chan = (pc300ch_t *)dev->chan;
+ 
pc300_t *card = (pc300_t *)chan->card;
+ 
int ch = chan->channel;
+ 
struct net_device_stats *stats = &dev->hdlc->stats;
+ 
unsigned long flags;
+ 
volatile pcsca_bd_t * ptdescr;
+ 
int i, nchar;
+ 
int tosend = len;
+ 
int nbuf = ((len - 1)/BD_DEF_LEN) + 1;
+ 
unsigned char *pdata=buf;
+
+ 
CPC_TTY_DBG("%s:cpc_tty_send_to_cars len=%i",
+ 
		(st_cpc_tty_area *)dev->cpc_tty->name,len);	
+
+ 
if (nbuf >= card->chan[ch].nfree_tx_bd) {
+ 
	return 1;
+ 
}
+ 

+ 
/* write buffer to DMA buffers */
+ 
CPC_TTY_DBG("%s: call dma_buf_write\n",
+ 
		(st_cpc_tty_area *)dev->cpc_tty->name);	
+ 
for (i = 0 ; i < nbuf ; i++) {
+ 
	ptdescr = (pcsca_bd_t *)(card->hw.rambase +
+ 
		TX_BD_ADDR(ch, card->chan[ch].tx_next_bd));
+ 
	nchar = (BD_DEF_LEN > tosend) ? tosend : BD_DEF_LEN;
+ 
	if (cpc_readb(&ptdescr->status) & DST_OSB) {
+ 
		memcpy_toio((void *)(card->hw.rambase +
+ 
			cpc_readl(&ptdescr->ptbuf)),
+ 
			&pdata[len - tosend],
+ 
			nchar);
+ 
		card->chan[ch].nfree_tx_bd--;
+ 
		if ((i + 1) == nbuf) {
+ 
			/* This must be the last BD to be used */
+ 
			cpc_writeb(&ptdescr->status, DST_EOM);
+ 
		} else {
+ 
			cpc_writeb(&ptdescr->status, 0);
+ 
		}
+ 
		cpc_writew(&ptdescr->len, nchar);
+ 
	} else {
+ 
		CPC_TTY_DBG("%s: error in dma_buf_write\n",
+ 
				(st_cpc_tty_area *)dev->cpc_tty->name);	
+ 
		stats->tx_dropped++;
+ 
		return 1;
+ 
	}
+ 
	tosend -= nchar;
+ 
	card->chan[ch].tx_next_bd =
+ 
		(card->chan[ch].tx_next_bd + 1) & (N_DMA_TX_BUF - 1);
+ 
}
+
+ 
if (dev->trace_on) {
+ 
	cpc_tty_trace(dev, buf, len,'T');
+ 
}
+
+ 
/* start transmission */
+ 
CPC_TTY_DBG("%s: start transmission\n",
+ 
	(st_cpc_tty_area *)dev->cpc_tty->name);	
+ 

+ 
CPC_TTY_LOCK(card, flags);
+ 
cpc_writeb(card->hw.scabase + DTX_REG(EDAL, ch),
+ 
		TX_BD_ADDR(ch, chan->tx_next_bd));
+ 
cpc_writeb(card->hw.scabase + M_REG(CMD, ch), CMD_TX_ENA);
+ 
cpc_writeb(card->hw.scabase + DSR_TX(ch), DSR_DE);
+
+ 
if (card->hw.type == PC300_TE) {
+ 
	cpc_writeb(card->hw.falcbase + card->hw.cpld_reg2,
+ 
		cpc_readb(card->hw.falcbase + card->hw.cpld_reg2) |
+ 
		(CPLD_REG2_FALC_LED1 << (2 * ch)));
+ 
}
+ 
CPC_TTY_UNLOCK(card, flags);
+ 
return 0;
+}
+
+/*
+ *	PC300 TTY trace routine
+ *
+ *  This routine send trace of connection to application.
+ *  o clear descriptors
+ *  o write data to DMA buffers
+ *  o start the transmission
+ */
+
+static void cpc_tty_trace(pc300dev_t *dev, char* buf, int len, char rxtx)
+{
+ 
struct sk_buff *skb;
+
+ 
if ((skb = dev_alloc_skb(10 + len)) == NULL) {
+ 
	/* out of memory */
+ 
	CPC_TTY_DBG("%s: tty_trace - out of memory\n",
+ 
		((struct net_device *)(dev->hdlc))->name);
+ 
	return;
+ 
}
+
+ 
skb_put (skb, 10 + len);
+ 
skb->dev = (struct net_device *) dev->hdlc;
+ 
skb->protocol = htons(ETH_P_CUST);
+ 
skb->mac.raw = skb->data;
+ 
skb->pkt_type = PACKET_HOST;
+ 
skb->len = 10 + len;
+
+ 
memcpy(skb->data,((struct net_device *)(dev->hdlc))->name,5);
+ 
skb->data[5] = '[';
+ 
skb->data[6] = rxtx;
+ 
skb->data[7] = ']';
+ 
skb->data[8] = ':';
+ 
skb->data[9] = ' ';
+ 
memcpy(&skb->data[10], buf, len);
+ 
netif_rx(skb);
+} 	
+
+/*
+ *	PC300 TTY unregister service routine
+ *
+ *	This routine unregister one interface.
+ */
+void cpc_tty_unregister_service(pc300dev_t *pc300dev)
+{
+ 
st_cpc_tty_area *cpc_tty;
+ 
ulong flags;
+ 
int res;
+
+ 
if ((cpc_tty= (st_cpc_tty_area *) pc300dev->cpc_tty) == 0) {
+ 
	CPC_TTY_DBG("%s: interface is not TTY\n",
+ 
		((struct net_device *)(pc300dev->hdlc))->name);
+ 
	return;
+ 
}
+ 
CPC_TTY_DBG("%s: cpc_tty_unregister_service", cpc_tty->name);
+
+ 
if (cpc_tty->pc300dev != pc300dev) {
+ 
	CPC_TTY_DBG("%s: invalid tty ptr=%s\n",
+ 
	((struct net_device *)(pc300dev->hdlc))->name, cpc_tty->name);
+ 
	return;
+ 
}
+
+ 
if (--cpc_tty_cnt == 0) {
+ 
	if (cpc_tty_refcount) {
+ 
		CPC_TTY_DBG("%s: unregister is not possible, refcount=%d",
+ 
						cpc_tty->name, cpc_tty_refcount);
+ 
		cpc_tty_cnt++;
+ 
		cpc_tty_unreg_flag = 1;
+ 
		return;
+ 
	} else {
+ 
		CPC_TTY_DBG("%s: unregister the tty driver\n", cpc_tty->name);
+ 
		if ((res=tty_unregister_driver(&serial_drv))) {
+ 
			CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
+ 
							cpc_tty->name,res);
+ 
		}
+ 
		if ((res=tty_unregister_driver(&callout_drv))) {
+ 
			CPC_TTY_DBG("%s: ERROR ->unregister the tty driver error=%d\n",
+ 
							cpc_tty->name,res);
+ 
		}
+ 
	}
+ 
}
+ 
CPC_TTY_LOCK(pc300dev->chan->card,flags);
+ 
cpc_tty->tty = NULL;
+ 
CPC_TTY_UNLOCK(pc300dev->chan->card, flags);
+ 
cpc_tty->tty_minor = 0;
+ 
cpc_tty->state = CPC_TTY_ST_IDLE;
+}
+
+/*
+ * PC300 TTY trigger poll routine
+ * This routine is called by pc300driver to treats Tx interrupt.
+ */
+void cpc_tty_trigger_poll(pc300dev_t *pc300dev)
+{
+ 
st_cpc_tty_area *cpc_tty = (st_cpc_tty_area *)pc300dev->cpc_tty;
+ 
if (!cpc_tty) {
+ 
	return;
+ 
}
+ 
schedule_task(&(cpc_tty->tty_tx_task_queue));
+}
+
+/*
+ * PC300 TTY reset var routine
+ * This routine is called by pc300driver to init the TTY area.
+ */
+
+void cpc_tty_reset_var(void)
+{
+ 
int i ;
+
+ 
CPC_TTY_DBG("hdlcX-tty: reset variables\n");
+ 
/* reset  the tty_driver structure - serial_drv */
+ 
memset(&serial_drv, 0, sizeof(struct tty_driver));
+ 
memset(&callout_drv, 0, sizeof(struct tty_driver));
+ 
for (i=0; i < CPC_TTY_NPORTS; i++){
+ 
	memset(&cpc_tty_area[i],0, sizeof(st_cpc_tty_area));
+ 
}
+}