patch-2.4.25 linux-2.4.25/drivers/net/wan/pc300_tty.c

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diff -urN linux-2.4.24/drivers/net/wan/pc300_tty.c linux-2.4.25/drivers/net/wan/pc300_tty.c
@@ -0,0 +1,1117 @@
+/*
+ * pc300_tty.c	Cyclades-PC300(tm) TTY Driver.
+ *
+ * Author:	Regina Kodato <reginak@cyclades.com>
+ * Maintainer:	PC300 Maintainer <pc300@cyclades.com>
+ *
+ * Copyright:	(c) 1999-2003 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;
+
+	/* 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)); 
+	}
+}
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)