Initial import

1 files changed, 4340 insertions, 0 deletions

diff --git a/drivers/char/pcmcia/synclink_cs.c b/drivers/char/pcmcia/synclink_cs.c
new file mode 100644
index 000000000..0ea998605
--- /dev/null
+++ b/drivers/char/pcmcia/synclink_cs.c
@@ -0,0 +1,4340 @@
+/*
+ * linux/drivers/char/pcmcia/synclink_cs.c
+ *
+ * $Id: synclink_cs.c,v 4.34 2005/09/08 13:20:54 paulkf Exp $
+ *
+ * Device driver for Microgate SyncLink PC Card
+ * multiprotocol serial adapter.
+ *
+ * written by Paul Fulghum for Microgate Corporation
+ * paulkf@microgate.com
+ *
+ * Microgate and SyncLink are trademarks of Microgate Corporation
+ *
+ * This code is released under the GNU General Public License (GPL)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#define VERSION(ver,rel,seq) (((ver)<<16) | ((rel)<<8) | (seq))
+#if defined(__i386__)
+#  define BREAKPOINT() asm("   int $3");
+#else
+#  define BREAKPOINT() { }
+#endif
+
+#define MAX_DEVICE_COUNT 4
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/major.h>
+#include <linux/string.h>
+#include <linux/fcntl.h>
+#include <linux/ptrace.h>
+#include <linux/ioport.h>
+#include <linux/mm.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/ioctl.h>
+#include <linux/synclink.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/dma.h>
+#include <linux/bitops.h>
+#include <asm/types.h>
+#include <linux/termios.h>
+#include <linux/workqueue.h>
+#include <linux/hdlc.h>
+
+#include <pcmcia/cistpl.h>
+#include <pcmcia/cisreg.h>
+#include <pcmcia/ds.h>
+
+#if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_CS_MODULE))
+#define SYNCLINK_GENERIC_HDLC 1
+#else
+#define SYNCLINK_GENERIC_HDLC 0
+#endif
+
+#define GET_USER(error,value,addr) error = get_user(value,addr)
+#define COPY_FROM_USER(error,dest,src,size) error = copy_from_user(dest,src,size) ? -EFAULT : 0
+#define PUT_USER(error,value,addr) error = put_user(value,addr)
+#define COPY_TO_USER(error,dest,src,size) error = copy_to_user(dest,src,size) ? -EFAULT : 0
+
+#include <asm/uaccess.h>
+
+static MGSL_PARAMS default_params = {
+	MGSL_MODE_HDLC,			/* unsigned long mode */
+	0,				/* unsigned char loopback; */
+	HDLC_FLAG_UNDERRUN_ABORT15,	/* unsigned short flags; */
+	HDLC_ENCODING_NRZI_SPACE,	/* unsigned char encoding; */
+	0,				/* unsigned long clock_speed; */
+	0xff,				/* unsigned char addr_filter; */
+	HDLC_CRC_16_CCITT,		/* unsigned short crc_type; */
+	HDLC_PREAMBLE_LENGTH_8BITS,	/* unsigned char preamble_length; */
+	HDLC_PREAMBLE_PATTERN_NONE,	/* unsigned char preamble; */
+	9600,				/* unsigned long data_rate; */
+	8,				/* unsigned char data_bits; */
+	1,				/* unsigned char stop_bits; */
+	ASYNC_PARITY_NONE		/* unsigned char parity; */
+};
+
+typedef struct {
+	int count;
+	unsigned char status;
+	char data[1];
+} RXBUF;
+
+/* The queue of BH actions to be performed */
+
+#define BH_RECEIVE  1
+#define BH_TRANSMIT 2
+#define BH_STATUS   4
+
+#define IO_PIN_SHUTDOWN_LIMIT 100
+
+#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
+
+struct _input_signal_events {
+	int	ri_up;
+	int	ri_down;
+	int	dsr_up;
+	int	dsr_down;
+	int	dcd_up;
+	int	dcd_down;
+	int	cts_up;
+	int	cts_down;
+};
+
+
+/*
+ * Device instance data structure
+ */
+
+typedef struct _mgslpc_info {
+	struct tty_port		port;
+	void *if_ptr;	/* General purpose pointer (used by SPPP) */
+	int			magic;
+	int			line;
+
+	struct mgsl_icount	icount;
+
+	int			timeout;
+	int			x_char;		/* xon/xoff character */
+	unsigned char		read_status_mask;
+	unsigned char		ignore_status_mask;
+
+	unsigned char *tx_buf;
+	int            tx_put;
+	int            tx_get;
+	int            tx_count;
+
+	/* circular list of fixed length rx buffers */
+
+	unsigned char  *rx_buf;        /* memory allocated for all rx buffers */
+	int            rx_buf_total_size; /* size of memory allocated for rx buffers */
+	int            rx_put;         /* index of next empty rx buffer */
+	int            rx_get;         /* index of next full rx buffer */
+	int            rx_buf_size;    /* size in bytes of single rx buffer */
+	int            rx_buf_count;   /* total number of rx buffers */
+	int            rx_frame_count; /* number of full rx buffers */
+
+	wait_queue_head_t	status_event_wait_q;
+	wait_queue_head_t	event_wait_q;
+	struct timer_list	tx_timer;	/* HDLC transmit timeout timer */
+	struct _mgslpc_info	*next_device;	/* device list link */
+
+	unsigned short imra_value;
+	unsigned short imrb_value;
+	unsigned char  pim_value;
+
+	spinlock_t lock;
+	struct work_struct task;		/* task structure for scheduling bh */
+
+	u32 max_frame_size;
+
+	u32 pending_bh;
+
+	bool bh_running;
+	bool bh_requested;
+
+	int dcd_chkcount; /* check counts to prevent */
+	int cts_chkcount; /* too many IRQs if a signal */
+	int dsr_chkcount; /* is floating */
+	int ri_chkcount;
+
+	bool rx_enabled;
+	bool rx_overflow;
+
+	bool tx_enabled;
+	bool tx_active;
+	bool tx_aborting;
+	u32 idle_mode;
+
+	int if_mode; /* serial interface selection (RS-232, v.35 etc) */
+
+	char device_name[25];		/* device instance name */
+
+	unsigned int io_base;	/* base I/O address of adapter */
+	unsigned int irq_level;
+
+	MGSL_PARAMS params;		/* communications parameters */
+
+	unsigned char serial_signals;	/* current serial signal states */
+
+	bool irq_occurred;		/* for diagnostics use */
+	char testing_irq;
+	unsigned int init_error;	/* startup error (DIAGS)	*/
+
+	char *flag_buf;
+	bool drop_rts_on_tx_done;
+
+	struct	_input_signal_events	input_signal_events;
+
+	/* PCMCIA support */
+	struct pcmcia_device	*p_dev;
+	int		      stop;
+
+	/* SPPP/Cisco HDLC device parts */
+	int netcount;
+	spinlock_t netlock;
+
+#if SYNCLINK_GENERIC_HDLC
+	struct net_device *netdev;
+#endif
+
+} MGSLPC_INFO;
+
+#define MGSLPC_MAGIC 0x5402
+
+/*
+ * The size of the serial xmit buffer is 1 page, or 4096 bytes
+ */
+#define TXBUFSIZE 4096
+
+
+#define CHA     0x00   /* channel A offset */
+#define CHB     0x40   /* channel B offset */
+
+/*
+ *  FIXME: PPC has PVR defined in asm/reg.h.  For now we just undef it.
+ */
+#undef PVR
+
+#define RXFIFO  0
+#define TXFIFO  0
+#define STAR    0x20
+#define CMDR    0x20
+#define RSTA    0x21
+#define PRE     0x21
+#define MODE    0x22
+#define TIMR    0x23
+#define XAD1    0x24
+#define XAD2    0x25
+#define RAH1    0x26
+#define RAH2    0x27
+#define DAFO    0x27
+#define RAL1    0x28
+#define RFC     0x28
+#define RHCR    0x29
+#define RAL2    0x29
+#define RBCL    0x2a
+#define XBCL    0x2a
+#define RBCH    0x2b
+#define XBCH    0x2b
+#define CCR0    0x2c
+#define CCR1    0x2d
+#define CCR2    0x2e
+#define CCR3    0x2f
+#define VSTR    0x34
+#define BGR     0x34
+#define RLCR    0x35
+#define AML     0x36
+#define AMH     0x37
+#define GIS     0x38
+#define IVA     0x38
+#define IPC     0x39
+#define ISR     0x3a
+#define IMR     0x3a
+#define PVR     0x3c
+#define PIS     0x3d
+#define PIM     0x3d
+#define PCR     0x3e
+#define CCR4    0x3f
+
+// IMR/ISR
+
+#define IRQ_BREAK_ON    BIT15   // rx break detected
+#define IRQ_DATAOVERRUN BIT14	// receive data overflow
+#define IRQ_ALLSENT     BIT13	// all sent
+#define IRQ_UNDERRUN    BIT12	// transmit data underrun
+#define IRQ_TIMER       BIT11	// timer interrupt
+#define IRQ_CTS         BIT10	// CTS status change
+#define IRQ_TXREPEAT    BIT9	// tx message repeat
+#define IRQ_TXFIFO      BIT8	// transmit pool ready
+#define IRQ_RXEOM       BIT7	// receive message end
+#define IRQ_EXITHUNT    BIT6	// receive frame start
+#define IRQ_RXTIME      BIT6    // rx char timeout
+#define IRQ_DCD         BIT2	// carrier detect status change
+#define IRQ_OVERRUN     BIT1	// receive frame overflow
+#define IRQ_RXFIFO      BIT0	// receive pool full
+
+// STAR
+
+#define XFW   BIT6		// transmit FIFO write enable
+#define CEC   BIT2		// command executing
+#define CTS   BIT1		// CTS state
+
+#define PVR_DTR      BIT0
+#define PVR_DSR      BIT1
+#define PVR_RI       BIT2
+#define PVR_AUTOCTS  BIT3
+#define PVR_RS232    0x20   /* 0010b */
+#define PVR_V35      0xe0   /* 1110b */
+#define PVR_RS422    0x40   /* 0100b */
+
+/* Register access functions */
+
+#define write_reg(info, reg, val) outb((val),(info)->io_base + (reg))
+#define read_reg(info, reg) inb((info)->io_base + (reg))
+
+#define read_reg16(info, reg) inw((info)->io_base + (reg))
+#define write_reg16(info, reg, val) outw((val), (info)->io_base + (reg))
+
+#define set_reg_bits(info, reg, mask) \
+	write_reg(info, (reg), \
+		 (unsigned char) (read_reg(info, (reg)) | (mask)))
+#define clear_reg_bits(info, reg, mask) \
+	write_reg(info, (reg), \
+		 (unsigned char) (read_reg(info, (reg)) & ~(mask)))
+/*
+ * interrupt enable/disable routines
+ */
+static void irq_disable(MGSLPC_INFO *info, unsigned char channel, unsigned short mask)
+{
+	if (channel == CHA) {
+		info->imra_value |= mask;
+		write_reg16(info, CHA + IMR, info->imra_value);
+	} else {
+		info->imrb_value |= mask;
+		write_reg16(info, CHB + IMR, info->imrb_value);
+	}
+}
+static void irq_enable(MGSLPC_INFO *info, unsigned char channel, unsigned short mask)
+{
+	if (channel == CHA) {
+		info->imra_value &= ~mask;
+		write_reg16(info, CHA + IMR, info->imra_value);
+	} else {
+		info->imrb_value &= ~mask;
+		write_reg16(info, CHB + IMR, info->imrb_value);
+	}
+}
+
+#define port_irq_disable(info, mask) \
+	{ info->pim_value |= (mask); write_reg(info, PIM, info->pim_value); }
+
+#define port_irq_enable(info, mask) \
+	{ info->pim_value &= ~(mask); write_reg(info, PIM, info->pim_value); }
+
+static void rx_start(MGSLPC_INFO *info);
+static void rx_stop(MGSLPC_INFO *info);
+
+static void tx_start(MGSLPC_INFO *info, struct tty_struct *tty);
+static void tx_stop(MGSLPC_INFO *info);
+static void tx_set_idle(MGSLPC_INFO *info);
+
+static void get_signals(MGSLPC_INFO *info);
+static void set_signals(MGSLPC_INFO *info);
+
+static void reset_device(MGSLPC_INFO *info);
+
+static void hdlc_mode(MGSLPC_INFO *info);
+static void async_mode(MGSLPC_INFO *info);
+
+static void tx_timeout(unsigned long context);
+
+static int carrier_raised(struct tty_port *port);
+static void dtr_rts(struct tty_port *port, int onoff);
+
+#if SYNCLINK_GENERIC_HDLC
+#define dev_to_port(D) (dev_to_hdlc(D)->priv)
+static void hdlcdev_tx_done(MGSLPC_INFO *info);
+static void hdlcdev_rx(MGSLPC_INFO *info, char *buf, int size);
+static int  hdlcdev_init(MGSLPC_INFO *info);
+static void hdlcdev_exit(MGSLPC_INFO *info);
+#endif
+
+static void trace_block(MGSLPC_INFO *info,const char* data, int count, int xmit);
+
+static bool register_test(MGSLPC_INFO *info);
+static bool irq_test(MGSLPC_INFO *info);
+static int adapter_test(MGSLPC_INFO *info);
+
+static int claim_resources(MGSLPC_INFO *info);
+static void release_resources(MGSLPC_INFO *info);
+static int mgslpc_add_device(MGSLPC_INFO *info);
+static void mgslpc_remove_device(MGSLPC_INFO *info);
+
+static bool rx_get_frame(MGSLPC_INFO *info, struct tty_struct *tty);
+static void rx_reset_buffers(MGSLPC_INFO *info);
+static int  rx_alloc_buffers(MGSLPC_INFO *info);
+static void rx_free_buffers(MGSLPC_INFO *info);
+
+static irqreturn_t mgslpc_isr(int irq, void *dev_id);
+
+/*
+ * Bottom half interrupt handlers
+ */
+static void bh_handler(struct work_struct *work);
+static void bh_transmit(MGSLPC_INFO *info, struct tty_struct *tty);
+static void bh_status(MGSLPC_INFO *info);
+
+/*
+ * ioctl handlers
+ */
+static int tiocmget(struct tty_struct *tty);
+static int tiocmset(struct tty_struct *tty,
+					unsigned int set, unsigned int clear);
+static int get_stats(MGSLPC_INFO *info, struct mgsl_icount __user *user_icount);
+static int get_params(MGSLPC_INFO *info, MGSL_PARAMS __user *user_params);
+static int set_params(MGSLPC_INFO *info, MGSL_PARAMS __user *new_params, struct tty_struct *tty);
+static int get_txidle(MGSLPC_INFO *info, int __user *idle_mode);
+static int set_txidle(MGSLPC_INFO *info, int idle_mode);
+static int set_txenable(MGSLPC_INFO *info, int enable, struct tty_struct *tty);
+static int tx_abort(MGSLPC_INFO *info);
+static int set_rxenable(MGSLPC_INFO *info, int enable);
+static int wait_events(MGSLPC_INFO *info, int __user *mask);
+
+static MGSLPC_INFO *mgslpc_device_list = NULL;
+static int mgslpc_device_count = 0;
+
+/*
+ * Set this param to non-zero to load eax with the
+ * .text section address and breakpoint on module load.
+ * This is useful for use with gdb and add-symbol-file command.
+ */
+static bool break_on_load=0;
+
+/*
+ * Driver major number, defaults to zero to get auto
+ * assigned major number. May be forced as module parameter.
+ */
+static int ttymajor=0;
+
+static int debug_level = 0;
+static int maxframe[MAX_DEVICE_COUNT] = {0,};
+
+module_param(break_on_load, bool, 0);
+module_param(ttymajor, int, 0);
+module_param(debug_level, int, 0);
+module_param_array(maxframe, int, NULL, 0);
+
+MODULE_LICENSE("GPL");
+
+static char *driver_name = "SyncLink PC Card driver";
+static char *driver_version = "$Revision: 4.34 $";
+
+static struct tty_driver *serial_driver;
+
+/* number of characters left in xmit buffer before we ask for more */
+#define WAKEUP_CHARS 256
+
+static void mgslpc_change_params(MGSLPC_INFO *info, struct tty_struct *tty);
+static void mgslpc_wait_until_sent(struct tty_struct *tty, int timeout);
+
+/* PCMCIA prototypes */
+
+static int mgslpc_config(struct pcmcia_device *link);
+static void mgslpc_release(u_long arg);
+static void mgslpc_detach(struct pcmcia_device *p_dev);
+
+/*
+ * 1st function defined in .text section. Calling this function in
+ * init_module() followed by a breakpoint allows a remote debugger
+ * (gdb) to get the .text address for the add-symbol-file command.
+ * This allows remote debugging of dynamically loadable modules.
+ */
+static void* mgslpc_get_text_ptr(void)
+{
+	return mgslpc_get_text_ptr;
+}
+
+/**
+ * line discipline callback wrappers
+ *
+ * The wrappers maintain line discipline references
+ * while calling into the line discipline.
+ *
+ * ldisc_receive_buf  - pass receive data to line discipline
+ */
+
+static void ldisc_receive_buf(struct tty_struct *tty,
+			      const __u8 *data, char *flags, int count)
+{
+	struct tty_ldisc *ld;
+	if (!tty)
+		return;
+	ld = tty_ldisc_ref(tty);
+	if (ld) {
+		if (ld->ops->receive_buf)
+			ld->ops->receive_buf(tty, data, flags, count);
+		tty_ldisc_deref(ld);
+	}
+}
+
+static const struct tty_port_operations mgslpc_port_ops = {
+	.carrier_raised = carrier_raised,
+	.dtr_rts = dtr_rts
+};
+
+static int mgslpc_probe(struct pcmcia_device *link)
+{
+	MGSLPC_INFO *info;
+	int ret;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("mgslpc_attach\n");
+
+	info = kzalloc(sizeof(MGSLPC_INFO), GFP_KERNEL);
+	if (!info) {
+		printk("Error can't allocate device instance data\n");
+		return -ENOMEM;
+	}
+
+	info->magic = MGSLPC_MAGIC;
+	tty_port_init(&info->port);
+	info->port.ops = &mgslpc_port_ops;
+	INIT_WORK(&info->task, bh_handler);
+	info->max_frame_size = 4096;
+	info->port.close_delay = 5*HZ/10;
+	info->port.closing_wait = 30*HZ;
+	init_waitqueue_head(&info->status_event_wait_q);
+	init_waitqueue_head(&info->event_wait_q);
+	spin_lock_init(&info->lock);
+	spin_lock_init(&info->netlock);
+	memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
+	info->idle_mode = HDLC_TXIDLE_FLAGS;
+	info->imra_value = 0xffff;
+	info->imrb_value = 0xffff;
+	info->pim_value = 0xff;
+
+	info->p_dev = link;
+	link->priv = info;
+
+	/* Initialize the struct pcmcia_device structure */
+
+	ret = mgslpc_config(link);
+	if (ret != 0)
+		goto failed;
+
+	ret = mgslpc_add_device(info);
+	if (ret != 0)
+		goto failed_release;
+
+	return 0;
+
+failed_release:
+	mgslpc_release((u_long)link);
+failed:
+	tty_port_destroy(&info->port);
+	kfree(info);
+	return ret;
+}
+
+/* Card has been inserted.
+ */
+
+static int mgslpc_ioprobe(struct pcmcia_device *p_dev, void *priv_data)
+{
+	return pcmcia_request_io(p_dev);
+}
+
+static int mgslpc_config(struct pcmcia_device *link)
+{
+	MGSLPC_INFO *info = link->priv;
+	int ret;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("mgslpc_config(0x%p)\n", link);
+
+	link->config_flags |= CONF_ENABLE_IRQ | CONF_AUTO_SET_IO;
+
+	ret = pcmcia_loop_config(link, mgslpc_ioprobe, NULL);
+	if (ret != 0)
+		goto failed;
+
+	link->config_index = 8;
+	link->config_regs = PRESENT_OPTION;
+
+	ret = pcmcia_request_irq(link, mgslpc_isr);
+	if (ret)
+		goto failed;
+	ret = pcmcia_enable_device(link);
+	if (ret)
+		goto failed;
+
+	info->io_base = link->resource[0]->start;
+	info->irq_level = link->irq;
+	return 0;
+
+failed:
+	mgslpc_release((u_long)link);
+	return -ENODEV;
+}
+
+/* Card has been removed.
+ * Unregister device and release PCMCIA configuration.
+ * If device is open, postpone until it is closed.
+ */
+static void mgslpc_release(u_long arg)
+{
+	struct pcmcia_device *link = (struct pcmcia_device *)arg;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("mgslpc_release(0x%p)\n", link);
+
+	pcmcia_disable_device(link);
+}
+
+static void mgslpc_detach(struct pcmcia_device *link)
+{
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("mgslpc_detach(0x%p)\n", link);
+
+	((MGSLPC_INFO *)link->priv)->stop = 1;
+	mgslpc_release((u_long)link);
+
+	mgslpc_remove_device((MGSLPC_INFO *)link->priv);
+}
+
+static int mgslpc_suspend(struct pcmcia_device *link)
+{
+	MGSLPC_INFO *info = link->priv;
+
+	info->stop = 1;
+
+	return 0;
+}
+
+static int mgslpc_resume(struct pcmcia_device *link)
+{
+	MGSLPC_INFO *info = link->priv;
+
+	info->stop = 0;
+
+	return 0;
+}
+
+
+static inline bool mgslpc_paranoia_check(MGSLPC_INFO *info,
+					char *name, const char *routine)
+{
+#ifdef MGSLPC_PARANOIA_CHECK
+	static const char *badmagic =
+		"Warning: bad magic number for mgsl struct (%s) in %s\n";
+	static const char *badinfo =
+		"Warning: null mgslpc_info for (%s) in %s\n";
+
+	if (!info) {
+		printk(badinfo, name, routine);
+		return true;
+	}
+	if (info->magic != MGSLPC_MAGIC) {
+		printk(badmagic, name, routine);
+		return true;
+	}
+#else
+	if (!info)
+		return true;
+#endif
+	return false;
+}
+
+
+#define CMD_RXFIFO      BIT7	// release current rx FIFO
+#define CMD_RXRESET     BIT6	// receiver reset
+#define CMD_RXFIFO_READ BIT5
+#define CMD_START_TIMER BIT4
+#define CMD_TXFIFO      BIT3	// release current tx FIFO
+#define CMD_TXEOM       BIT1	// transmit end message
+#define CMD_TXRESET     BIT0	// transmit reset
+
+static bool wait_command_complete(MGSLPC_INFO *info, unsigned char channel)
+{
+	int i = 0;
+	/* wait for command completion */
+	while (read_reg(info, (unsigned char)(channel+STAR)) & BIT2) {
+		udelay(1);
+		if (i++ == 1000)
+			return false;
+	}
+	return true;
+}
+
+static void issue_command(MGSLPC_INFO *info, unsigned char channel, unsigned char cmd)
+{
+	wait_command_complete(info, channel);
+	write_reg(info, (unsigned char) (channel + CMDR), cmd);
+}
+
+static void tx_pause(struct tty_struct *tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (mgslpc_paranoia_check(info, tty->name, "tx_pause"))
+		return;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("tx_pause(%s)\n", info->device_name);
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (info->tx_enabled)
+		tx_stop(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+static void tx_release(struct tty_struct *tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (mgslpc_paranoia_check(info, tty->name, "tx_release"))
+		return;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("tx_release(%s)\n", info->device_name);
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (!info->tx_enabled)
+		tx_start(info, tty);
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+/* Return next bottom half action to perform.
+ * or 0 if nothing to do.
+ */
+static int bh_action(MGSLPC_INFO *info)
+{
+	unsigned long flags;
+	int rc = 0;
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	if (info->pending_bh & BH_RECEIVE) {
+		info->pending_bh &= ~BH_RECEIVE;
+		rc = BH_RECEIVE;
+	} else if (info->pending_bh & BH_TRANSMIT) {
+		info->pending_bh &= ~BH_TRANSMIT;
+		rc = BH_TRANSMIT;
+	} else if (info->pending_bh & BH_STATUS) {
+		info->pending_bh &= ~BH_STATUS;
+		rc = BH_STATUS;
+	}
+
+	if (!rc) {
+		/* Mark BH routine as complete */
+		info->bh_running = false;
+		info->bh_requested = false;
+	}
+
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	return rc;
+}
+
+static void bh_handler(struct work_struct *work)
+{
+	MGSLPC_INFO *info = container_of(work, MGSLPC_INFO, task);
+	struct tty_struct *tty;
+	int action;
+
+	if (debug_level >= DEBUG_LEVEL_BH)
+		printk("%s(%d):bh_handler(%s) entry\n",
+			__FILE__,__LINE__,info->device_name);
+
+	info->bh_running = true;
+	tty = tty_port_tty_get(&info->port);
+
+	while((action = bh_action(info)) != 0) {
+
+		/* Process work item */
+		if (debug_level >= DEBUG_LEVEL_BH)
+			printk("%s(%d):bh_handler() work item action=%d\n",
+				__FILE__,__LINE__,action);
+
+		switch (action) {
+
+		case BH_RECEIVE:
+			while(rx_get_frame(info, tty));
+			break;
+		case BH_TRANSMIT:
+			bh_transmit(info, tty);
+			break;
+		case BH_STATUS:
+			bh_status(info);
+			break;
+		default:
+			/* unknown work item ID */
+			printk("Unknown work item ID=%08X!\n", action);
+			break;
+		}
+	}
+
+	tty_kref_put(tty);
+	if (debug_level >= DEBUG_LEVEL_BH)
+		printk("%s(%d):bh_handler(%s) exit\n",
+			__FILE__,__LINE__,info->device_name);
+}
+
+static void bh_transmit(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	if (debug_level >= DEBUG_LEVEL_BH)
+		printk("bh_transmit() entry on %s\n", info->device_name);
+
+	if (tty)
+		tty_wakeup(tty);
+}
+
+static void bh_status(MGSLPC_INFO *info)
+{
+	info->ri_chkcount = 0;
+	info->dsr_chkcount = 0;
+	info->dcd_chkcount = 0;
+	info->cts_chkcount = 0;
+}
+
+/* eom: non-zero = end of frame */
+static void rx_ready_hdlc(MGSLPC_INFO *info, int eom)
+{
+	unsigned char data[2];
+	unsigned char fifo_count, read_count, i;
+	RXBUF *buf = (RXBUF*)(info->rx_buf + (info->rx_put * info->rx_buf_size));
+
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):rx_ready_hdlc(eom=%d)\n", __FILE__, __LINE__, eom);
+
+	if (!info->rx_enabled)
+		return;
+
+	if (info->rx_frame_count >= info->rx_buf_count) {
+		/* no more free buffers */
+		issue_command(info, CHA, CMD_RXRESET);
+		info->pending_bh |= BH_RECEIVE;
+		info->rx_overflow = true;
+		info->icount.buf_overrun++;
+		return;
+	}
+
+	if (eom) {
+		/* end of frame, get FIFO count from RBCL register */
+		fifo_count = (unsigned char)(read_reg(info, CHA+RBCL) & 0x1f);
+		if (fifo_count == 0)
+			fifo_count = 32;
+	} else
+		fifo_count = 32;
+
+	do {
+		if (fifo_count == 1) {
+			read_count = 1;
+			data[0] = read_reg(info, CHA + RXFIFO);
+		} else {
+			read_count = 2;
+			*((unsigned short *) data) = read_reg16(info, CHA + RXFIFO);
+		}
+		fifo_count -= read_count;
+		if (!fifo_count && eom)
+			buf->status = data[--read_count];
+
+		for (i = 0; i < read_count; i++) {
+			if (buf->count >= info->max_frame_size) {
+				/* frame too large, reset receiver and reset current buffer */
+				issue_command(info, CHA, CMD_RXRESET);
+				buf->count = 0;
+				return;
+			}
+			*(buf->data + buf->count) = data[i];
+			buf->count++;
+		}
+	} while (fifo_count);
+
+	if (eom) {
+		info->pending_bh |= BH_RECEIVE;
+		info->rx_frame_count++;
+		info->rx_put++;
+		if (info->rx_put >= info->rx_buf_count)
+			info->rx_put = 0;
+	}
+	issue_command(info, CHA, CMD_RXFIFO);
+}
+
+static void rx_ready_async(MGSLPC_INFO *info, int tcd)
+{
+	struct tty_port *port = &info->port;
+	unsigned char data, status, flag;
+	int fifo_count;
+	int work = 0;
+	struct mgsl_icount *icount = &info->icount;
+
+	if (tcd) {
+		/* early termination, get FIFO count from RBCL register */
+		fifo_count = (unsigned char)(read_reg(info, CHA+RBCL) & 0x1f);
+
+		/* Zero fifo count could mean 0 or 32 bytes available.
+		 * If BIT5 of STAR is set then at least 1 byte is available.
+		 */
+		if (!fifo_count && (read_reg(info,CHA+STAR) & BIT5))
+			fifo_count = 32;
+	} else
+		fifo_count = 32;
+
+	tty_buffer_request_room(port, fifo_count);
+	/* Flush received async data to receive data buffer. */
+	while (fifo_count) {
+		data   = read_reg(info, CHA + RXFIFO);
+		status = read_reg(info, CHA + RXFIFO);
+		fifo_count -= 2;
+
+		icount->rx++;
+		flag = TTY_NORMAL;
+
+		// if no frameing/crc error then save data
+		// BIT7:parity error
+		// BIT6:framing error
+
+		if (status & (BIT7 + BIT6)) {
+			if (status & BIT7)
+				icount->parity++;
+			else
+				icount->frame++;
+
+			/* discard char if tty control flags say so */
+			if (status & info->ignore_status_mask)
+				continue;
+
+			status &= info->read_status_mask;
+
+			if (status & BIT7)
+				flag = TTY_PARITY;
+			else if (status & BIT6)
+				flag = TTY_FRAME;
+		}
+		work += tty_insert_flip_char(port, data, flag);
+	}
+	issue_command(info, CHA, CMD_RXFIFO);
+
+	if (debug_level >= DEBUG_LEVEL_ISR) {
+		printk("%s(%d):rx_ready_async",
+			__FILE__,__LINE__);
+		printk("%s(%d):rx=%d brk=%d parity=%d frame=%d overrun=%d\n",
+			__FILE__,__LINE__,icount->rx,icount->brk,
+			icount->parity,icount->frame,icount->overrun);
+	}
+
+	if (work)
+		tty_flip_buffer_push(port);
+}
+
+
+static void tx_done(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	if (!info->tx_active)
+		return;
+
+	info->tx_active = false;
+	info->tx_aborting = false;
+
+	if (info->params.mode == MGSL_MODE_ASYNC)
+		return;
+
+	info->tx_count = info->tx_put = info->tx_get = 0;
+	del_timer(&info->tx_timer);
+
+	if (info->drop_rts_on_tx_done) {
+		get_signals(info);
+		if (info->serial_signals & SerialSignal_RTS) {
+			info->serial_signals &= ~SerialSignal_RTS;
+			set_signals(info);
+		}
+		info->drop_rts_on_tx_done = false;
+	}
+
+#if SYNCLINK_GENERIC_HDLC
+	if (info->netcount)
+		hdlcdev_tx_done(info);
+	else
+#endif
+	{
+		if (tty && (tty->stopped || tty->hw_stopped)) {
+			tx_stop(info);
+			return;
+		}
+		info->pending_bh |= BH_TRANSMIT;
+	}
+}
+
+static void tx_ready(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	unsigned char fifo_count = 32;
+	int c;
+
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):tx_ready(%s)\n", __FILE__, __LINE__, info->device_name);
+
+	if (info->params.mode == MGSL_MODE_HDLC) {
+		if (!info->tx_active)
+			return;
+	} else {
+		if (tty && (tty->stopped || tty->hw_stopped)) {
+			tx_stop(info);
+			return;
+		}
+		if (!info->tx_count)
+			info->tx_active = false;
+	}
+
+	if (!info->tx_count)
+		return;
+
+	while (info->tx_count && fifo_count) {
+		c = min(2, min_t(int, fifo_count, min(info->tx_count, TXBUFSIZE - info->tx_get)));
+
+		if (c == 1) {
+			write_reg(info, CHA + TXFIFO, *(info->tx_buf + info->tx_get));
+		} else {
+			write_reg16(info, CHA + TXFIFO,
+					  *((unsigned short*)(info->tx_buf + info->tx_get)));
+		}
+		info->tx_count -= c;
+		info->tx_get = (info->tx_get + c) & (TXBUFSIZE - 1);
+		fifo_count -= c;
+	}
+
+	if (info->params.mode == MGSL_MODE_ASYNC) {
+		if (info->tx_count < WAKEUP_CHARS)
+			info->pending_bh |= BH_TRANSMIT;
+		issue_command(info, CHA, CMD_TXFIFO);
+	} else {
+		if (info->tx_count)
+			issue_command(info, CHA, CMD_TXFIFO);
+		else
+			issue_command(info, CHA, CMD_TXFIFO + CMD_TXEOM);
+	}
+}
+
+static void cts_change(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	get_signals(info);
+	if ((info->cts_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
+		irq_disable(info, CHB, IRQ_CTS);
+	info->icount.cts++;
+	if (info->serial_signals & SerialSignal_CTS)
+		info->input_signal_events.cts_up++;
+	else
+		info->input_signal_events.cts_down++;
+	wake_up_interruptible(&info->status_event_wait_q);
+	wake_up_interruptible(&info->event_wait_q);
+
+	if (tty && tty_port_cts_enabled(&info->port)) {
+		if (tty->hw_stopped) {
+			if (info->serial_signals & SerialSignal_CTS) {
+				if (debug_level >= DEBUG_LEVEL_ISR)
+					printk("CTS tx start...");
+				tty->hw_stopped = 0;
+				tx_start(info, tty);
+				info->pending_bh |= BH_TRANSMIT;
+				return;
+			}
+		} else {
+			if (!(info->serial_signals & SerialSignal_CTS)) {
+				if (debug_level >= DEBUG_LEVEL_ISR)
+					printk("CTS tx stop...");
+				tty->hw_stopped = 1;
+				tx_stop(info);
+			}
+		}
+	}
+	info->pending_bh |= BH_STATUS;
+}
+
+static void dcd_change(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	get_signals(info);
+	if ((info->dcd_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
+		irq_disable(info, CHB, IRQ_DCD);
+	info->icount.dcd++;
+	if (info->serial_signals & SerialSignal_DCD) {
+		info->input_signal_events.dcd_up++;
+	}
+	else
+		info->input_signal_events.dcd_down++;
+#if SYNCLINK_GENERIC_HDLC
+	if (info->netcount) {
+		if (info->serial_signals & SerialSignal_DCD)
+			netif_carrier_on(info->netdev);
+		else
+			netif_carrier_off(info->netdev);
+	}
+#endif
+	wake_up_interruptible(&info->status_event_wait_q);
+	wake_up_interruptible(&info->event_wait_q);
+
+	if (info->port.flags & ASYNC_CHECK_CD) {
+		if (debug_level >= DEBUG_LEVEL_ISR)
+			printk("%s CD now %s...", info->device_name,
+			       (info->serial_signals & SerialSignal_DCD) ? "on" : "off");
+		if (info->serial_signals & SerialSignal_DCD)
+			wake_up_interruptible(&info->port.open_wait);
+		else {
+			if (debug_level >= DEBUG_LEVEL_ISR)
+				printk("doing serial hangup...");
+			if (tty)
+				tty_hangup(tty);
+		}
+	}
+	info->pending_bh |= BH_STATUS;
+}
+
+static void dsr_change(MGSLPC_INFO *info)
+{
+	get_signals(info);
+	if ((info->dsr_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
+		port_irq_disable(info, PVR_DSR);
+	info->icount.dsr++;
+	if (info->serial_signals & SerialSignal_DSR)
+		info->input_signal_events.dsr_up++;
+	else
+		info->input_signal_events.dsr_down++;
+	wake_up_interruptible(&info->status_event_wait_q);
+	wake_up_interruptible(&info->event_wait_q);
+	info->pending_bh |= BH_STATUS;
+}
+
+static void ri_change(MGSLPC_INFO *info)
+{
+	get_signals(info);
+	if ((info->ri_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
+		port_irq_disable(info, PVR_RI);
+	info->icount.rng++;
+	if (info->serial_signals & SerialSignal_RI)
+		info->input_signal_events.ri_up++;
+	else
+		info->input_signal_events.ri_down++;
+	wake_up_interruptible(&info->status_event_wait_q);
+	wake_up_interruptible(&info->event_wait_q);
+	info->pending_bh |= BH_STATUS;
+}
+
+/* Interrupt service routine entry point.
+ *
+ * Arguments:
+ *
+ * irq     interrupt number that caused interrupt
+ * dev_id  device ID supplied during interrupt registration
+ */
+static irqreturn_t mgslpc_isr(int dummy, void *dev_id)
+{
+	MGSLPC_INFO *info = dev_id;
+	struct tty_struct *tty;
+	unsigned short isr;
+	unsigned char gis, pis;
+	int count=0;
+
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("mgslpc_isr(%d) entry.\n", info->irq_level);
+
+	if (!(info->p_dev->_locked))
+		return IRQ_HANDLED;
+
+	tty = tty_port_tty_get(&info->port);
+
+	spin_lock(&info->lock);
+
+	while ((gis = read_reg(info, CHA + GIS))) {
+		if (debug_level >= DEBUG_LEVEL_ISR)
+			printk("mgslpc_isr %s gis=%04X\n", info->device_name,gis);
+
+		if ((gis & 0x70) || count > 1000) {
+			printk("synclink_cs:hardware failed or ejected\n");
+			break;
+		}
+		count++;
+
+		if (gis & (BIT1 | BIT0)) {
+			isr = read_reg16(info, CHB + ISR);
+			if (isr & IRQ_DCD)
+				dcd_change(info, tty);
+			if (isr & IRQ_CTS)
+				cts_change(info, tty);
+		}
+		if (gis & (BIT3 | BIT2))
+		{
+			isr = read_reg16(info, CHA + ISR);
+			if (isr & IRQ_TIMER) {
+				info->irq_occurred = true;
+				irq_disable(info, CHA, IRQ_TIMER);
+			}
+
+			/* receive IRQs */
+			if (isr & IRQ_EXITHUNT) {
+				info->icount.exithunt++;
+				wake_up_interruptible(&info->event_wait_q);
+			}
+			if (isr & IRQ_BREAK_ON) {
+				info->icount.brk++;
+				if (info->port.flags & ASYNC_SAK)
+					do_SAK(tty);
+			}
+			if (isr & IRQ_RXTIME) {
+				issue_command(info, CHA, CMD_RXFIFO_READ);
+			}
+			if (isr & (IRQ_RXEOM | IRQ_RXFIFO)) {
+				if (info->params.mode == MGSL_MODE_HDLC)
+					rx_ready_hdlc(info, isr & IRQ_RXEOM);
+				else
+					rx_ready_async(info, isr & IRQ_RXEOM);
+			}
+
+			/* transmit IRQs */
+			if (isr & IRQ_UNDERRUN) {
+				if (info->tx_aborting)
+					info->icount.txabort++;
+				else
+					info->icount.txunder++;
+				tx_done(info, tty);
+			}
+			else if (isr & IRQ_ALLSENT) {
+				info->icount.txok++;
+				tx_done(info, tty);
+			}
+			else if (isr & IRQ_TXFIFO)
+				tx_ready(info, tty);
+		}
+		if (gis & BIT7) {
+			pis = read_reg(info, CHA + PIS);
+			if (pis & BIT1)
+				dsr_change(info);
+			if (pis & BIT2)
+				ri_change(info);
+		}
+	}
+
+	/* Request bottom half processing if there's something
+	 * for it to do and the bh is not already running
+	 */
+
+	if (info->pending_bh && !info->bh_running && !info->bh_requested) {
+		if (debug_level >= DEBUG_LEVEL_ISR)
+			printk("%s(%d):%s queueing bh task.\n",
+				__FILE__,__LINE__,info->device_name);
+		schedule_work(&info->task);
+		info->bh_requested = true;
+	}
+
+	spin_unlock(&info->lock);
+	tty_kref_put(tty);
+
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):mgslpc_isr(%d)exit.\n",
+		       __FILE__, __LINE__, info->irq_level);
+
+	return IRQ_HANDLED;
+}
+
+/* Initialize and start device.
+ */
+static int startup(MGSLPC_INFO * info, struct tty_struct *tty)
+{
+	int retval = 0;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):startup(%s)\n", __FILE__, __LINE__, info->device_name);
+
+	if (info->port.flags & ASYNC_INITIALIZED)
+		return 0;
+
+	if (!info->tx_buf) {
+		/* allocate a page of memory for a transmit buffer */
+		info->tx_buf = (unsigned char *)get_zeroed_page(GFP_KERNEL);
+		if (!info->tx_buf) {
+			printk(KERN_ERR"%s(%d):%s can't allocate transmit buffer\n",
+				__FILE__, __LINE__, info->device_name);
+			return -ENOMEM;
+		}
+	}
+
+	info->pending_bh = 0;
+
+	memset(&info->icount, 0, sizeof(info->icount));
+
+	setup_timer(&info->tx_timer, tx_timeout, (unsigned long)info);
+
+	/* Allocate and claim adapter resources */
+	retval = claim_resources(info);
+
+	/* perform existence check and diagnostics */
+	if (!retval)
+		retval = adapter_test(info);
+
+	if (retval) {
+		if (capable(CAP_SYS_ADMIN) && tty)
+			set_bit(TTY_IO_ERROR, &tty->flags);
+		release_resources(info);
+		return retval;
+	}
+
+	/* program hardware for current parameters */
+	mgslpc_change_params(info, tty);
+
+	if (tty)
+		clear_bit(TTY_IO_ERROR, &tty->flags);
+
+	info->port.flags |= ASYNC_INITIALIZED;
+
+	return 0;
+}
+
+/* Called by mgslpc_close() and mgslpc_hangup() to shutdown hardware
+ */
+static void shutdown(MGSLPC_INFO * info, struct tty_struct *tty)
+{
+	unsigned long flags;
+
+	if (!(info->port.flags & ASYNC_INITIALIZED))
+		return;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_shutdown(%s)\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	/* clear status wait queue because status changes */
+	/* can't happen after shutting down the hardware */
+	wake_up_interruptible(&info->status_event_wait_q);
+	wake_up_interruptible(&info->event_wait_q);
+
+	del_timer_sync(&info->tx_timer);
+
+	if (info->tx_buf) {
+		free_page((unsigned long) info->tx_buf);
+		info->tx_buf = NULL;
+	}
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	rx_stop(info);
+	tx_stop(info);
+
+	/* TODO:disable interrupts instead of reset to preserve signal states */
+	reset_device(info);
+
+	if (!tty || tty->termios.c_cflag & HUPCL) {
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+		set_signals(info);
+	}
+
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	release_resources(info);
+
+	if (tty)
+		set_bit(TTY_IO_ERROR, &tty->flags);
+
+	info->port.flags &= ~ASYNC_INITIALIZED;
+}
+
+static void mgslpc_program_hw(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	rx_stop(info);
+	tx_stop(info);
+	info->tx_count = info->tx_put = info->tx_get = 0;
+
+	if (info->params.mode == MGSL_MODE_HDLC || info->netcount)
+		hdlc_mode(info);
+	else
+		async_mode(info);
+
+	set_signals(info);
+
+	info->dcd_chkcount = 0;
+	info->cts_chkcount = 0;
+	info->ri_chkcount = 0;
+	info->dsr_chkcount = 0;
+
+	irq_enable(info, CHB, IRQ_DCD | IRQ_CTS);
+	port_irq_enable(info, (unsigned char) PVR_DSR | PVR_RI);
+	get_signals(info);
+
+	if (info->netcount || (tty && (tty->termios.c_cflag & CREAD)))
+		rx_start(info);
+
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+/* Reconfigure adapter based on new parameters
+ */
+static void mgslpc_change_params(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	unsigned cflag;
+	int bits_per_char;
+
+	if (!tty)
+		return;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_change_params(%s)\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	cflag = tty->termios.c_cflag;
+
+	/* if B0 rate (hangup) specified then negate RTS and DTR */
+	/* otherwise assert RTS and DTR */
+	if (cflag & CBAUD)
+		info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
+	else
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+
+	/* byte size and parity */
+
+	switch (cflag & CSIZE) {
+	case CS5: info->params.data_bits = 5; break;
+	case CS6: info->params.data_bits = 6; break;
+	case CS7: info->params.data_bits = 7; break;
+	case CS8: info->params.data_bits = 8; break;
+	default:  info->params.data_bits = 7; break;
+	}
+
+	if (cflag & CSTOPB)
+		info->params.stop_bits = 2;
+	else
+		info->params.stop_bits = 1;
+
+	info->params.parity = ASYNC_PARITY_NONE;
+	if (cflag & PARENB) {
+		if (cflag & PARODD)
+			info->params.parity = ASYNC_PARITY_ODD;
+		else
+			info->params.parity = ASYNC_PARITY_EVEN;
+#ifdef CMSPAR
+		if (cflag & CMSPAR)
+			info->params.parity = ASYNC_PARITY_SPACE;
+#endif
+	}
+
+	/* calculate number of jiffies to transmit a full
+	 * FIFO (32 bytes) at specified data rate
+	 */
+	bits_per_char = info->params.data_bits +
+			info->params.stop_bits + 1;
+
+	/* if port data rate is set to 460800 or less then
+	 * allow tty settings to override, otherwise keep the
+	 * current data rate.
+	 */
+	if (info->params.data_rate <= 460800) {
+		info->params.data_rate = tty_get_baud_rate(tty);
+	}
+
+	if (info->params.data_rate) {
+		info->timeout = (32*HZ*bits_per_char) /
+				info->params.data_rate;
+	}
+	info->timeout += HZ/50;		/* Add .02 seconds of slop */
+
+	if (cflag & CRTSCTS)
+		info->port.flags |= ASYNC_CTS_FLOW;
+	else
+		info->port.flags &= ~ASYNC_CTS_FLOW;
+
+	if (cflag & CLOCAL)
+		info->port.flags &= ~ASYNC_CHECK_CD;
+	else
+		info->port.flags |= ASYNC_CHECK_CD;
+
+	/* process tty input control flags */
+
+	info->read_status_mask = 0;
+	if (I_INPCK(tty))
+		info->read_status_mask |= BIT7 | BIT6;
+	if (I_IGNPAR(tty))
+		info->ignore_status_mask |= BIT7 | BIT6;
+
+	mgslpc_program_hw(info, tty);
+}
+
+/* Add a character to the transmit buffer
+ */
+static int mgslpc_put_char(struct tty_struct *tty, unsigned char ch)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO) {
+		printk("%s(%d):mgslpc_put_char(%d) on %s\n",
+			__FILE__, __LINE__, ch, info->device_name);
+	}
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_put_char"))
+		return 0;
+
+	if (!info->tx_buf)
+		return 0;
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	if (info->params.mode == MGSL_MODE_ASYNC || !info->tx_active) {
+		if (info->tx_count < TXBUFSIZE - 1) {
+			info->tx_buf[info->tx_put++] = ch;
+			info->tx_put &= TXBUFSIZE-1;
+			info->tx_count++;
+		}
+	}
+
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 1;
+}
+
+/* Enable transmitter so remaining characters in the
+ * transmit buffer are sent.
+ */
+static void mgslpc_flush_chars(struct tty_struct *tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_flush_chars() entry on %s tx_count=%d\n",
+			__FILE__, __LINE__, info->device_name, info->tx_count);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_flush_chars"))
+		return;
+
+	if (info->tx_count <= 0 || tty->stopped ||
+	    tty->hw_stopped || !info->tx_buf)
+		return;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_flush_chars() entry on %s starting transmitter\n",
+			__FILE__, __LINE__, info->device_name);
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (!info->tx_active)
+		tx_start(info, tty);
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+/* Send a block of data
+ *
+ * Arguments:
+ *
+ * tty        pointer to tty information structure
+ * buf	      pointer to buffer containing send data
+ * count      size of send data in bytes
+ *
+ * Returns: number of characters written
+ */
+static int mgslpc_write(struct tty_struct * tty,
+			const unsigned char *buf, int count)
+{
+	int c, ret = 0;
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_write(%s) count=%d\n",
+			__FILE__, __LINE__, info->device_name, count);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_write") ||
+		!info->tx_buf)
+		goto cleanup;
+
+	if (info->params.mode == MGSL_MODE_HDLC) {
+		if (count > TXBUFSIZE) {
+			ret = -EIO;
+			goto cleanup;
+		}
+		if (info->tx_active)
+			goto cleanup;
+		else if (info->tx_count)
+			goto start;
+	}
+
+	for (;;) {
+		c = min(count,
+			min(TXBUFSIZE - info->tx_count - 1,
+			    TXBUFSIZE - info->tx_put));
+		if (c <= 0)
+			break;
+
+		memcpy(info->tx_buf + info->tx_put, buf, c);
+
+		spin_lock_irqsave(&info->lock, flags);
+		info->tx_put = (info->tx_put + c) & (TXBUFSIZE-1);
+		info->tx_count += c;
+		spin_unlock_irqrestore(&info->lock, flags);
+
+		buf += c;
+		count -= c;
+		ret += c;
+	}
+start:
+	if (info->tx_count && !tty->stopped && !tty->hw_stopped) {
+		spin_lock_irqsave(&info->lock, flags);
+		if (!info->tx_active)
+			tx_start(info, tty);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+cleanup:
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_write(%s) returning=%d\n",
+			__FILE__, __LINE__, info->device_name, ret);
+	return ret;
+}
+
+/* Return the count of free bytes in transmit buffer
+ */
+static int mgslpc_write_room(struct tty_struct *tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	int ret;
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_write_room"))
+		return 0;
+
+	if (info->params.mode == MGSL_MODE_HDLC) {
+		/* HDLC (frame oriented) mode */
+		if (info->tx_active)
+			return 0;
+		else
+			return HDLC_MAX_FRAME_SIZE;
+	} else {
+		ret = TXBUFSIZE - info->tx_count - 1;
+		if (ret < 0)
+			ret = 0;
+	}
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_write_room(%s)=%d\n",
+			 __FILE__, __LINE__, info->device_name, ret);
+	return ret;
+}
+
+/* Return the count of bytes in transmit buffer
+ */
+static int mgslpc_chars_in_buffer(struct tty_struct *tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	int rc;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_chars_in_buffer(%s)\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_chars_in_buffer"))
+		return 0;
+
+	if (info->params.mode == MGSL_MODE_HDLC)
+		rc = info->tx_active ? info->max_frame_size : 0;
+	else
+		rc = info->tx_count;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_chars_in_buffer(%s)=%d\n",
+			 __FILE__, __LINE__, info->device_name, rc);
+
+	return rc;
+}
+
+/* Discard all data in the send buffer
+ */
+static void mgslpc_flush_buffer(struct tty_struct *tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_flush_buffer(%s) entry\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_flush_buffer"))
+		return;
+
+	spin_lock_irqsave(&info->lock, flags);
+	info->tx_count = info->tx_put = info->tx_get = 0;
+	del_timer(&info->tx_timer);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	wake_up_interruptible(&tty->write_wait);
+	tty_wakeup(tty);
+}
+
+/* Send a high-priority XON/XOFF character
+ */
+static void mgslpc_send_xchar(struct tty_struct *tty, char ch)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_send_xchar(%s,%d)\n",
+			 __FILE__, __LINE__, info->device_name, ch);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_send_xchar"))
+		return;
+
+	info->x_char = ch;
+	if (ch) {
+		spin_lock_irqsave(&info->lock, flags);
+		if (!info->tx_enabled)
+			tx_start(info, tty);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+}
+
+/* Signal remote device to throttle send data (our receive data)
+ */
+static void mgslpc_throttle(struct tty_struct * tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_throttle(%s) entry\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_throttle"))
+		return;
+
+	if (I_IXOFF(tty))
+		mgslpc_send_xchar(tty, STOP_CHAR(tty));
+
+	if (tty->termios.c_cflag & CRTSCTS) {
+		spin_lock_irqsave(&info->lock, flags);
+		info->serial_signals &= ~SerialSignal_RTS;
+		set_signals(info);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+}
+
+/* Signal remote device to stop throttling send data (our receive data)
+ */
+static void mgslpc_unthrottle(struct tty_struct * tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_unthrottle(%s) entry\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_unthrottle"))
+		return;
+
+	if (I_IXOFF(tty)) {
+		if (info->x_char)
+			info->x_char = 0;
+		else
+			mgslpc_send_xchar(tty, START_CHAR(tty));
+	}
+
+	if (tty->termios.c_cflag & CRTSCTS) {
+		spin_lock_irqsave(&info->lock, flags);
+		info->serial_signals |= SerialSignal_RTS;
+		set_signals(info);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+}
+
+/* get the current serial statistics
+ */
+static int get_stats(MGSLPC_INFO * info, struct mgsl_icount __user *user_icount)
+{
+	int err;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("get_params(%s)\n", info->device_name);
+	if (!user_icount) {
+		memset(&info->icount, 0, sizeof(info->icount));
+	} else {
+		COPY_TO_USER(err, user_icount, &info->icount, sizeof(struct mgsl_icount));
+		if (err)
+			return -EFAULT;
+	}
+	return 0;
+}
+
+/* get the current serial parameters
+ */
+static int get_params(MGSLPC_INFO * info, MGSL_PARAMS __user *user_params)
+{
+	int err;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("get_params(%s)\n", info->device_name);
+	COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
+	if (err)
+		return -EFAULT;
+	return 0;
+}
+
+/* set the serial parameters
+ *
+ * Arguments:
+ *
+ *	info		pointer to device instance data
+ *	new_params	user buffer containing new serial params
+ *
+ * Returns:	0 if success, otherwise error code
+ */
+static int set_params(MGSLPC_INFO * info, MGSL_PARAMS __user *new_params, struct tty_struct *tty)
+{
+	unsigned long flags;
+	MGSL_PARAMS tmp_params;
+	int err;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):set_params %s\n", __FILE__,__LINE__,
+			info->device_name);
+	COPY_FROM_USER(err,&tmp_params, new_params, sizeof(MGSL_PARAMS));
+	if (err) {
+		if (debug_level >= DEBUG_LEVEL_INFO)
+			printk("%s(%d):set_params(%s) user buffer copy failed\n",
+				__FILE__, __LINE__, info->device_name);
+		return -EFAULT;
+	}
+
+	spin_lock_irqsave(&info->lock, flags);
+	memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	mgslpc_change_params(info, tty);
+
+	return 0;
+}
+
+static int get_txidle(MGSLPC_INFO * info, int __user *idle_mode)
+{
+	int err;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("get_txidle(%s)=%d\n", info->device_name, info->idle_mode);
+	COPY_TO_USER(err,idle_mode, &info->idle_mode, sizeof(int));
+	if (err)
+		return -EFAULT;
+	return 0;
+}
+
+static int set_txidle(MGSLPC_INFO * info, int idle_mode)
+{
+	unsigned long flags;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("set_txidle(%s,%d)\n", info->device_name, idle_mode);
+	spin_lock_irqsave(&info->lock, flags);
+	info->idle_mode = idle_mode;
+	tx_set_idle(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+static int get_interface(MGSLPC_INFO * info, int __user *if_mode)
+{
+	int err;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("get_interface(%s)=%d\n", info->device_name, info->if_mode);
+	COPY_TO_USER(err,if_mode, &info->if_mode, sizeof(int));
+	if (err)
+		return -EFAULT;
+	return 0;
+}
+
+static int set_interface(MGSLPC_INFO * info, int if_mode)
+{
+	unsigned long flags;
+	unsigned char val;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("set_interface(%s,%d)\n", info->device_name, if_mode);
+	spin_lock_irqsave(&info->lock, flags);
+	info->if_mode = if_mode;
+
+	val = read_reg(info, PVR) & 0x0f;
+	switch (info->if_mode)
+	{
+	case MGSL_INTERFACE_RS232: val |= PVR_RS232; break;
+	case MGSL_INTERFACE_V35:   val |= PVR_V35;   break;
+	case MGSL_INTERFACE_RS422: val |= PVR_RS422; break;
+	}
+	write_reg(info, PVR, val);
+
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+static int set_txenable(MGSLPC_INFO * info, int enable, struct tty_struct *tty)
+{
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("set_txenable(%s,%d)\n", info->device_name, enable);
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (enable) {
+		if (!info->tx_enabled)
+			tx_start(info, tty);
+	} else {
+		if (info->tx_enabled)
+			tx_stop(info);
+	}
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+static int tx_abort(MGSLPC_INFO * info)
+{
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("tx_abort(%s)\n", info->device_name);
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (info->tx_active && info->tx_count &&
+	    info->params.mode == MGSL_MODE_HDLC) {
+		/* clear data count so FIFO is not filled on next IRQ.
+		 * This results in underrun and abort transmission.
+		 */
+		info->tx_count = info->tx_put = info->tx_get = 0;
+		info->tx_aborting = true;
+	}
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+static int set_rxenable(MGSLPC_INFO * info, int enable)
+{
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("set_rxenable(%s,%d)\n", info->device_name, enable);
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (enable) {
+		if (!info->rx_enabled)
+			rx_start(info);
+	} else {
+		if (info->rx_enabled)
+			rx_stop(info);
+	}
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+/* wait for specified event to occur
+ *
+ * Arguments:		info	pointer to device instance data
+ *			mask	pointer to bitmask of events to wait for
+ * Return Value:	0	if successful and bit mask updated with
+ *				of events triggerred,
+ *			otherwise error code
+ */
+static int wait_events(MGSLPC_INFO * info, int __user *mask_ptr)
+{
+	unsigned long flags;
+	int s;
+	int rc=0;
+	struct mgsl_icount cprev, cnow;
+	int events;
+	int mask;
+	struct	_input_signal_events oldsigs, newsigs;
+	DECLARE_WAITQUEUE(wait, current);
+
+	COPY_FROM_USER(rc,&mask, mask_ptr, sizeof(int));
+	if (rc)
+		return  -EFAULT;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("wait_events(%s,%d)\n", info->device_name, mask);
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	/* return immediately if state matches requested events */
+	get_signals(info);
+	s = info->serial_signals;
+	events = mask &
+		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
+		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
+		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
+		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
+	if (events) {
+		spin_unlock_irqrestore(&info->lock, flags);
+		goto exit;
+	}
+
+	/* save current irq counts */
+	cprev = info->icount;
+	oldsigs = info->input_signal_events;
+
+	if ((info->params.mode == MGSL_MODE_HDLC) &&
+	    (mask & MgslEvent_ExitHuntMode))
+		irq_enable(info, CHA, IRQ_EXITHUNT);
+
+	set_current_state(TASK_INTERRUPTIBLE);
+	add_wait_queue(&info->event_wait_q, &wait);
+
+	spin_unlock_irqrestore(&info->lock, flags);
+
+
+	for(;;) {
+		schedule();
+		if (signal_pending(current)) {
+			rc = -ERESTARTSYS;
+			break;
+		}
+
+		/* get current irq counts */
+		spin_lock_irqsave(&info->lock, flags);
+		cnow = info->icount;
+		newsigs = info->input_signal_events;
+		set_current_state(TASK_INTERRUPTIBLE);
+		spin_unlock_irqrestore(&info->lock, flags);
+
+		/* if no change, wait aborted for some reason */
+		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
+		    newsigs.dsr_down == oldsigs.dsr_down &&
+		    newsigs.dcd_up   == oldsigs.dcd_up   &&
+		    newsigs.dcd_down == oldsigs.dcd_down &&
+		    newsigs.cts_up   == oldsigs.cts_up   &&
+		    newsigs.cts_down == oldsigs.cts_down &&
+		    newsigs.ri_up    == oldsigs.ri_up    &&
+		    newsigs.ri_down  == oldsigs.ri_down  &&
+		    cnow.exithunt    == cprev.exithunt   &&
+		    cnow.rxidle      == cprev.rxidle) {
+			rc = -EIO;
+			break;
+		}
+
+		events = mask &
+			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
+			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
+			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
+			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
+			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
+			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
+			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
+			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
+			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
+			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
+		if (events)
+			break;
+
+		cprev = cnow;
+		oldsigs = newsigs;
+	}
+
+	remove_wait_queue(&info->event_wait_q, &wait);
+	set_current_state(TASK_RUNNING);
+
+	if (mask & MgslEvent_ExitHuntMode) {
+		spin_lock_irqsave(&info->lock, flags);
+		if (!waitqueue_active(&info->event_wait_q))
+			irq_disable(info, CHA, IRQ_EXITHUNT);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+exit:
+	if (rc == 0)
+		PUT_USER(rc, events, mask_ptr);
+	return rc;
+}
+
+static int modem_input_wait(MGSLPC_INFO *info,int arg)
+{
+	unsigned long flags;
+	int rc;
+	struct mgsl_icount cprev, cnow;
+	DECLARE_WAITQUEUE(wait, current);
+
+	/* save current irq counts */
+	spin_lock_irqsave(&info->lock, flags);
+	cprev = info->icount;
+	add_wait_queue(&info->status_event_wait_q, &wait);
+	set_current_state(TASK_INTERRUPTIBLE);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	for(;;) {
+		schedule();
+		if (signal_pending(current)) {
+			rc = -ERESTARTSYS;
+			break;
+		}
+
+		/* get new irq counts */
+		spin_lock_irqsave(&info->lock, flags);
+		cnow = info->icount;
+		set_current_state(TASK_INTERRUPTIBLE);
+		spin_unlock_irqrestore(&info->lock, flags);
+
+		/* if no change, wait aborted for some reason */
+		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
+		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
+			rc = -EIO;
+			break;
+		}
+
+		/* check for change in caller specified modem input */
+		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
+		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
+		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
+		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
+			rc = 0;
+			break;
+		}
+
+		cprev = cnow;
+	}
+	remove_wait_queue(&info->status_event_wait_q, &wait);
+	set_current_state(TASK_RUNNING);
+	return rc;
+}
+
+/* return the state of the serial control and status signals
+ */
+static int tiocmget(struct tty_struct *tty)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned int result;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+	get_signals(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
+		((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
+		((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
+		((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
+		((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
+		((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS:0);
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):%s tiocmget() value=%08X\n",
+			 __FILE__, __LINE__, info->device_name, result);
+	return result;
+}
+
+/* set modem control signals (DTR/RTS)
+ */
+static int tiocmset(struct tty_struct *tty,
+		    unsigned int set, unsigned int clear)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):%s tiocmset(%x,%x)\n",
+			__FILE__, __LINE__, info->device_name, set, clear);
+
+	if (set & TIOCM_RTS)
+		info->serial_signals |= SerialSignal_RTS;
+	if (set & TIOCM_DTR)
+		info->serial_signals |= SerialSignal_DTR;
+	if (clear & TIOCM_RTS)
+		info->serial_signals &= ~SerialSignal_RTS;
+	if (clear & TIOCM_DTR)
+		info->serial_signals &= ~SerialSignal_DTR;
+
+	spin_lock_irqsave(&info->lock, flags);
+	set_signals(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	return 0;
+}
+
+/* Set or clear transmit break condition
+ *
+ * Arguments:		tty		pointer to tty instance data
+ *			break_state	-1=set break condition, 0=clear
+ */
+static int mgslpc_break(struct tty_struct *tty, int break_state)
+{
+	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_break(%s,%d)\n",
+			 __FILE__, __LINE__, info->device_name, break_state);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_break"))
+		return -EINVAL;
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (break_state == -1)
+		set_reg_bits(info, CHA+DAFO, BIT6);
+	else
+		clear_reg_bits(info, CHA+DAFO, BIT6);
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+static int mgslpc_get_icount(struct tty_struct *tty,
+				struct serial_icounter_struct *icount)
+{
+	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
+	struct mgsl_icount cnow;	/* kernel counter temps */
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+	cnow = info->icount;
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->frame = cnow.frame;
+	icount->overrun = cnow.overrun;
+	icount->parity = cnow.parity;
+	icount->brk = cnow.brk;
+	icount->buf_overrun = cnow.buf_overrun;
+
+	return 0;
+}
+
+/* Service an IOCTL request
+ *
+ * Arguments:
+ *
+ *	tty	pointer to tty instance data
+ *	cmd	IOCTL command code
+ *	arg	command argument/context
+ *
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgslpc_ioctl(struct tty_struct *tty,
+			unsigned int cmd, unsigned long arg)
+{
+	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
+	void __user *argp = (void __user *)arg;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_ioctl %s cmd=%08X\n", __FILE__, __LINE__,
+			info->device_name, cmd);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_ioctl"))
+		return -ENODEV;
+
+	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
+	    (cmd != TIOCMIWAIT)) {
+		if (tty->flags & (1 << TTY_IO_ERROR))
+		    return -EIO;
+	}
+
+	switch (cmd) {
+	case MGSL_IOCGPARAMS:
+		return get_params(info, argp);
+	case MGSL_IOCSPARAMS:
+		return set_params(info, argp, tty);
+	case MGSL_IOCGTXIDLE:
+		return get_txidle(info, argp);
+	case MGSL_IOCSTXIDLE:
+		return set_txidle(info, (int)arg);
+	case MGSL_IOCGIF:
+		return get_interface(info, argp);
+	case MGSL_IOCSIF:
+		return set_interface(info,(int)arg);
+	case MGSL_IOCTXENABLE:
+		return set_txenable(info,(int)arg, tty);
+	case MGSL_IOCRXENABLE:
+		return set_rxenable(info,(int)arg);
+	case MGSL_IOCTXABORT:
+		return tx_abort(info);
+	case MGSL_IOCGSTATS:
+		return get_stats(info, argp);
+	case MGSL_IOCWAITEVENT:
+		return wait_events(info, argp);
+	case TIOCMIWAIT:
+		return modem_input_wait(info,(int)arg);
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+/* Set new termios settings
+ *
+ * Arguments:
+ *
+ *	tty		pointer to tty structure
+ *	termios		pointer to buffer to hold returned old termios
+ */
+static void mgslpc_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_set_termios %s\n", __FILE__, __LINE__,
+			tty->driver->name);
+
+	/* just return if nothing has changed */
+	if ((tty->termios.c_cflag == old_termios->c_cflag)
+	    && (RELEVANT_IFLAG(tty->termios.c_iflag)
+		== RELEVANT_IFLAG(old_termios->c_iflag)))
+	  return;
+
+	mgslpc_change_params(info, tty);
+
+	/* Handle transition to B0 status */
+	if (old_termios->c_cflag & CBAUD &&
+	    !(tty->termios.c_cflag & CBAUD)) {
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+		spin_lock_irqsave(&info->lock, flags);
+		set_signals(info);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+
+	/* Handle transition away from B0 status */
+	if (!(old_termios->c_cflag & CBAUD) &&
+	    tty->termios.c_cflag & CBAUD) {
+		info->serial_signals |= SerialSignal_DTR;
+		if (!(tty->termios.c_cflag & CRTSCTS) ||
+		    !test_bit(TTY_THROTTLED, &tty->flags)) {
+			info->serial_signals |= SerialSignal_RTS;
+		}
+		spin_lock_irqsave(&info->lock, flags);
+		set_signals(info);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+
+	/* Handle turning off CRTSCTS */
+	if (old_termios->c_cflag & CRTSCTS &&
+	    !(tty->termios.c_cflag & CRTSCTS)) {
+		tty->hw_stopped = 0;
+		tx_release(tty);
+	}
+}
+
+static void mgslpc_close(struct tty_struct *tty, struct file * filp)
+{
+	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
+	struct tty_port *port = &info->port;
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_close"))
+		return;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_close(%s) entry, count=%d\n",
+			 __FILE__, __LINE__, info->device_name, port->count);
+
+	if (tty_port_close_start(port, tty, filp) == 0)
+		goto cleanup;
+
+	if (port->flags & ASYNC_INITIALIZED)
+		mgslpc_wait_until_sent(tty, info->timeout);
+
+	mgslpc_flush_buffer(tty);
+
+	tty_ldisc_flush(tty);
+	shutdown(info, tty);
+	
+	tty_port_close_end(port, tty);
+	tty_port_tty_set(port, NULL);
+cleanup:
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_close(%s) exit, count=%d\n", __FILE__, __LINE__,
+			tty->driver->name, port->count);
+}
+
+/* Wait until the transmitter is empty.
+ */
+static void mgslpc_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
+	unsigned long orig_jiffies, char_time;
+
+	if (!info)
+		return;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_wait_until_sent(%s) entry\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_wait_until_sent"))
+		return;
+
+	if (!(info->port.flags & ASYNC_INITIALIZED))
+		goto exit;
+
+	orig_jiffies = jiffies;
+
+	/* Set check interval to 1/5 of estimated time to
+	 * send a character, and make it at least 1. The check
+	 * interval should also be less than the timeout.
+	 * Note: use tight timings here to satisfy the NIST-PCTS.
+	 */
+
+	if (info->params.data_rate) {
+	     	char_time = info->timeout/(32 * 5);
+		if (!char_time)
+			char_time++;
+	} else
+		char_time = 1;
+
+	if (timeout)
+		char_time = min_t(unsigned long, char_time, timeout);
+
+	if (info->params.mode == MGSL_MODE_HDLC) {
+		while (info->tx_active) {
+			msleep_interruptible(jiffies_to_msecs(char_time));
+			if (signal_pending(current))
+				break;
+			if (timeout && time_after(jiffies, orig_jiffies + timeout))
+				break;
+		}
+	} else {
+		while ((info->tx_count || info->tx_active) &&
+			info->tx_enabled) {
+			msleep_interruptible(jiffies_to_msecs(char_time));
+			if (signal_pending(current))
+				break;
+			if (timeout && time_after(jiffies, orig_jiffies + timeout))
+				break;
+		}
+	}
+
+exit:
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_wait_until_sent(%s) exit\n",
+			 __FILE__, __LINE__, info->device_name);
+}
+
+/* Called by tty_hangup() when a hangup is signaled.
+ * This is the same as closing all open files for the port.
+ */
+static void mgslpc_hangup(struct tty_struct *tty)
+{
+	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_hangup(%s)\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_hangup"))
+		return;
+
+	mgslpc_flush_buffer(tty);
+	shutdown(info, tty);
+	tty_port_hangup(&info->port);
+}
+
+static int carrier_raised(struct tty_port *port)
+{
+	MGSLPC_INFO *info = container_of(port, MGSLPC_INFO, port);
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+	get_signals(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	if (info->serial_signals & SerialSignal_DCD)
+		return 1;
+	return 0;
+}
+
+static void dtr_rts(struct tty_port *port, int onoff)
+{
+	MGSLPC_INFO *info = container_of(port, MGSLPC_INFO, port);
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (onoff)
+		info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
+	else
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+	set_signals(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+
+static int mgslpc_open(struct tty_struct *tty, struct file * filp)
+{
+	MGSLPC_INFO	*info;
+	struct tty_port *port;
+	int		retval, line;
+	unsigned long	flags;
+
+	/* verify range of specified line number */
+	line = tty->index;
+	if (line >= mgslpc_device_count) {
+		printk("%s(%d):mgslpc_open with invalid line #%d.\n",
+			__FILE__, __LINE__, line);
+		return -ENODEV;
+	}
+
+	/* find the info structure for the specified line */
+	info = mgslpc_device_list;
+	while(info && info->line != line)
+		info = info->next_device;
+	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_open"))
+		return -ENODEV;
+
+	port = &info->port;
+	tty->driver_data = info;
+	tty_port_tty_set(port, tty);
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_open(%s), old ref count = %d\n",
+			 __FILE__, __LINE__, tty->driver->name, port->count);
+
+	/* If port is closing, signal caller to try again */
+	if (port->flags & ASYNC_CLOSING){
+		wait_event_interruptible_tty(tty, port->close_wait,
+					     !(port->flags & ASYNC_CLOSING));
+		retval = ((port->flags & ASYNC_HUP_NOTIFY) ?
+			-EAGAIN : -ERESTARTSYS);
+		goto cleanup;
+	}
+
+	port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+
+	spin_lock_irqsave(&info->netlock, flags);
+	if (info->netcount) {
+		retval = -EBUSY;
+		spin_unlock_irqrestore(&info->netlock, flags);
+		goto cleanup;
+	}
+	spin_lock(&port->lock);
+	port->count++;
+	spin_unlock(&port->lock);
+	spin_unlock_irqrestore(&info->netlock, flags);
+
+	if (port->count == 1) {
+		/* 1st open on this device, init hardware */
+		retval = startup(info, tty);
+		if (retval < 0)
+			goto cleanup;
+	}
+
+	retval = tty_port_block_til_ready(&info->port, tty, filp);
+	if (retval) {
+		if (debug_level >= DEBUG_LEVEL_INFO)
+			printk("%s(%d):block_til_ready(%s) returned %d\n",
+				 __FILE__, __LINE__, info->device_name, retval);
+		goto cleanup;
+	}
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgslpc_open(%s) success\n",
+			 __FILE__, __LINE__, info->device_name);
+	retval = 0;
+
+cleanup:
+	return retval;
+}
+
+/*
+ * /proc fs routines....
+ */
+
+static inline void line_info(struct seq_file *m, MGSLPC_INFO *info)
+{
+	char	stat_buf[30];
+	unsigned long flags;
+
+	seq_printf(m, "%s:io:%04X irq:%d",
+		      info->device_name, info->io_base, info->irq_level);
+
+	/* output current serial signal states */
+	spin_lock_irqsave(&info->lock, flags);
+	get_signals(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	stat_buf[0] = 0;
+	stat_buf[1] = 0;
+	if (info->serial_signals & SerialSignal_RTS)
+		strcat(stat_buf, "|RTS");
+	if (info->serial_signals & SerialSignal_CTS)
+		strcat(stat_buf, "|CTS");
+	if (info->serial_signals & SerialSignal_DTR)
+		strcat(stat_buf, "|DTR");
+	if (info->serial_signals & SerialSignal_DSR)
+		strcat(stat_buf, "|DSR");
+	if (info->serial_signals & SerialSignal_DCD)
+		strcat(stat_buf, "|CD");
+	if (info->serial_signals & SerialSignal_RI)
+		strcat(stat_buf, "|RI");
+
+	if (info->params.mode == MGSL_MODE_HDLC) {
+		seq_printf(m, " HDLC txok:%d rxok:%d",
+			      info->icount.txok, info->icount.rxok);
+		if (info->icount.txunder)
+			seq_printf(m, " txunder:%d", info->icount.txunder);
+		if (info->icount.txabort)
+			seq_printf(m, " txabort:%d", info->icount.txabort);
+		if (info->icount.rxshort)
+			seq_printf(m, " rxshort:%d", info->icount.rxshort);
+		if (info->icount.rxlong)
+			seq_printf(m, " rxlong:%d", info->icount.rxlong);
+		if (info->icount.rxover)
+			seq_printf(m, " rxover:%d", info->icount.rxover);
+		if (info->icount.rxcrc)
+			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
+	} else {
+		seq_printf(m, " ASYNC tx:%d rx:%d",
+			      info->icount.tx, info->icount.rx);
+		if (info->icount.frame)
+			seq_printf(m, " fe:%d", info->icount.frame);
+		if (info->icount.parity)
+			seq_printf(m, " pe:%d", info->icount.parity);
+		if (info->icount.brk)
+			seq_printf(m, " brk:%d", info->icount.brk);
+		if (info->icount.overrun)
+			seq_printf(m, " oe:%d", info->icount.overrun);
+	}
+
+	/* Append serial signal status to end */
+	seq_printf(m, " %s\n", stat_buf+1);
+
+	seq_printf(m, "txactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
+		       info->tx_active,info->bh_requested,info->bh_running,
+		       info->pending_bh);
+}
+
+/* Called to print information about devices
+ */
+static int mgslpc_proc_show(struct seq_file *m, void *v)
+{
+	MGSLPC_INFO *info;
+
+	seq_printf(m, "synclink driver:%s\n", driver_version);
+
+	info = mgslpc_device_list;
+	while (info) {
+		line_info(m, info);
+		info = info->next_device;
+	}
+	return 0;
+}
+
+static int mgslpc_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, mgslpc_proc_show, NULL);
+}
+
+static const struct file_operations mgslpc_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= mgslpc_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int rx_alloc_buffers(MGSLPC_INFO *info)
+{
+	/* each buffer has header and data */
+	info->rx_buf_size = sizeof(RXBUF) + info->max_frame_size;
+
+	/* calculate total allocation size for 8 buffers */
+	info->rx_buf_total_size = info->rx_buf_size * 8;
+
+	/* limit total allocated memory */
+	if (info->rx_buf_total_size > 0x10000)
+		info->rx_buf_total_size = 0x10000;
+
+	/* calculate number of buffers */
+	info->rx_buf_count = info->rx_buf_total_size / info->rx_buf_size;
+
+	info->rx_buf = kmalloc(info->rx_buf_total_size, GFP_KERNEL);
+	if (info->rx_buf == NULL)
+		return -ENOMEM;
+
+	/* unused flag buffer to satisfy receive_buf calling interface */
+	info->flag_buf = kzalloc(info->max_frame_size, GFP_KERNEL);
+	if (!info->flag_buf) {
+		kfree(info->rx_buf);
+		info->rx_buf = NULL;
+		return -ENOMEM;
+	}
+	
+	rx_reset_buffers(info);
+	return 0;
+}
+
+static void rx_free_buffers(MGSLPC_INFO *info)
+{
+	kfree(info->rx_buf);
+	info->rx_buf = NULL;
+	kfree(info->flag_buf);
+	info->flag_buf = NULL;
+}
+
+static int claim_resources(MGSLPC_INFO *info)
+{
+	if (rx_alloc_buffers(info) < 0) {
+		printk("Can't allocate rx buffer %s\n", info->device_name);
+		release_resources(info);
+		return -ENODEV;
+	}
+	return 0;
+}
+
+static void release_resources(MGSLPC_INFO *info)
+{
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("release_resources(%s)\n", info->device_name);
+	rx_free_buffers(info);
+}
+
+/* Add the specified device instance data structure to the
+ * global linked list of devices and increment the device count.
+ *
+ * Arguments:		info	pointer to device instance data
+ */
+static int mgslpc_add_device(MGSLPC_INFO *info)
+{
+	MGSLPC_INFO *current_dev = NULL;
+	struct device *tty_dev;
+	int ret;
+
+	info->next_device = NULL;
+	info->line = mgslpc_device_count;
+	sprintf(info->device_name,"ttySLP%d",info->line);
+
+	if (info->line < MAX_DEVICE_COUNT) {
+		if (maxframe[info->line])
+			info->max_frame_size = maxframe[info->line];
+	}
+
+	mgslpc_device_count++;
+
+	if (!mgslpc_device_list)
+		mgslpc_device_list = info;
+	else {
+		current_dev = mgslpc_device_list;
+		while (current_dev->next_device)
+			current_dev = current_dev->next_device;
+		current_dev->next_device = info;
+	}
+
+	if (info->max_frame_size < 4096)
+		info->max_frame_size = 4096;
+	else if (info->max_frame_size > 65535)
+		info->max_frame_size = 65535;
+
+	printk("SyncLink PC Card %s:IO=%04X IRQ=%d\n",
+		info->device_name, info->io_base, info->irq_level);
+
+#if SYNCLINK_GENERIC_HDLC
+	ret = hdlcdev_init(info);
+	if (ret != 0)
+		goto failed;
+#endif
+
+	tty_dev = tty_port_register_device(&info->port, serial_driver, info->line,
+			&info->p_dev->dev);
+	if (IS_ERR(tty_dev)) {
+		ret = PTR_ERR(tty_dev);
+#if SYNCLINK_GENERIC_HDLC
+		hdlcdev_exit(info);
+#endif
+		goto failed;
+	}
+
+	return 0;
+
+failed:
+	if (current_dev)
+		current_dev->next_device = NULL;
+	else
+		mgslpc_device_list = NULL;
+	mgslpc_device_count--;
+	return ret;
+}
+
+static void mgslpc_remove_device(MGSLPC_INFO *remove_info)
+{
+	MGSLPC_INFO *info = mgslpc_device_list;
+	MGSLPC_INFO *last = NULL;
+
+	while(info) {
+		if (info == remove_info) {
+			if (last)
+				last->next_device = info->next_device;
+			else
+				mgslpc_device_list = info->next_device;
+			tty_unregister_device(serial_driver, info->line);
+#if SYNCLINK_GENERIC_HDLC
+			hdlcdev_exit(info);
+#endif
+			release_resources(info);
+			tty_port_destroy(&info->port);
+			kfree(info);
+			mgslpc_device_count--;
+			return;
+		}
+		last = info;
+		info = info->next_device;
+	}
+}
+
+static const struct pcmcia_device_id mgslpc_ids[] = {
+	PCMCIA_DEVICE_MANF_CARD(0x02c5, 0x0050),
+	PCMCIA_DEVICE_NULL
+};
+MODULE_DEVICE_TABLE(pcmcia, mgslpc_ids);
+
+static struct pcmcia_driver mgslpc_driver = {
+	.owner		= THIS_MODULE,
+	.name		= "synclink_cs",
+	.probe		= mgslpc_probe,
+	.remove		= mgslpc_detach,
+	.id_table	= mgslpc_ids,
+	.suspend	= mgslpc_suspend,
+	.resume		= mgslpc_resume,
+};
+
+static const struct tty_operations mgslpc_ops = {
+	.open = mgslpc_open,
+	.close = mgslpc_close,
+	.write = mgslpc_write,
+	.put_char = mgslpc_put_char,
+	.flush_chars = mgslpc_flush_chars,
+	.write_room = mgslpc_write_room,
+	.chars_in_buffer = mgslpc_chars_in_buffer,
+	.flush_buffer = mgslpc_flush_buffer,
+	.ioctl = mgslpc_ioctl,
+	.throttle = mgslpc_throttle,
+	.unthrottle = mgslpc_unthrottle,
+	.send_xchar = mgslpc_send_xchar,
+	.break_ctl = mgslpc_break,
+	.wait_until_sent = mgslpc_wait_until_sent,
+	.set_termios = mgslpc_set_termios,
+	.stop = tx_pause,
+	.start = tx_release,
+	.hangup = mgslpc_hangup,
+	.tiocmget = tiocmget,
+	.tiocmset = tiocmset,
+	.get_icount = mgslpc_get_icount,
+	.proc_fops = &mgslpc_proc_fops,
+};
+
+static int __init synclink_cs_init(void)
+{
+	int rc;
+
+	if (break_on_load) {
+		mgslpc_get_text_ptr();
+		BREAKPOINT();
+	}
+
+	serial_driver = tty_alloc_driver(MAX_DEVICE_COUNT,
+			TTY_DRIVER_REAL_RAW |
+			TTY_DRIVER_DYNAMIC_DEV);
+	if (IS_ERR(serial_driver)) {
+		rc = PTR_ERR(serial_driver);
+		goto err;
+	}
+
+	/* Initialize the tty_driver structure */
+	serial_driver->driver_name = "synclink_cs";
+	serial_driver->name = "ttySLP";
+	serial_driver->major = ttymajor;
+	serial_driver->minor_start = 64;
+	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
+	serial_driver->subtype = SERIAL_TYPE_NORMAL;
+	serial_driver->init_termios = tty_std_termios;
+	serial_driver->init_termios.c_cflag =
+	B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+	tty_set_operations(serial_driver, &mgslpc_ops);
+
+	rc = tty_register_driver(serial_driver);
+	if (rc < 0) {
+		printk(KERN_ERR "%s(%d):Couldn't register serial driver\n",
+				__FILE__, __LINE__);
+		goto err_put_tty;
+	}
+
+	rc = pcmcia_register_driver(&mgslpc_driver);
+	if (rc < 0)
+		goto err_unreg_tty;
+
+	printk(KERN_INFO "%s %s, tty major#%d\n", driver_name, driver_version,
+			serial_driver->major);
+
+	return 0;
+err_unreg_tty:
+	tty_unregister_driver(serial_driver);
+err_put_tty:
+	put_tty_driver(serial_driver);
+err:
+	return rc;
+}
+
+static void __exit synclink_cs_exit(void)
+{
+	pcmcia_unregister_driver(&mgslpc_driver);
+	tty_unregister_driver(serial_driver);
+	put_tty_driver(serial_driver);
+}
+
+module_init(synclink_cs_init);
+module_exit(synclink_cs_exit);
+
+static void mgslpc_set_rate(MGSLPC_INFO *info, unsigned char channel, unsigned int rate)
+{
+	unsigned int M, N;
+	unsigned char val;
+
+	/* note:standard BRG mode is broken in V3.2 chip
+	 * so enhanced mode is always used
+	 */
+
+	if (rate) {
+		N = 3686400 / rate;
+		if (!N)
+			N = 1;
+		N >>= 1;
+		for (M = 1; N > 64 && M < 16; M++)
+			N >>= 1;
+		N--;
+
+		/* BGR[5..0] = N
+		 * BGR[9..6] = M
+		 * BGR[7..0] contained in BGR register
+		 * BGR[9..8] contained in CCR2[7..6]
+		 * divisor = (N+1)*2^M
+		 *
+		 * Note: M *must* not be zero (causes asymetric duty cycle)
+		 */
+		write_reg(info, (unsigned char) (channel + BGR),
+				  (unsigned char) ((M << 6) + N));
+		val = read_reg(info, (unsigned char) (channel + CCR2)) & 0x3f;
+		val |= ((M << 4) & 0xc0);
+		write_reg(info, (unsigned char) (channel + CCR2), val);
+	}
+}
+
+/* Enabled the AUX clock output at the specified frequency.
+ */
+static void enable_auxclk(MGSLPC_INFO *info)
+{
+	unsigned char val;
+
+	/* MODE
+	 *
+	 * 07..06  MDS[1..0] 10 = transparent HDLC mode
+	 * 05      ADM Address Mode, 0 = no addr recognition
+	 * 04      TMD Timer Mode, 0 = external
+	 * 03      RAC Receiver Active, 0 = inactive
+	 * 02      RTS 0=RTS active during xmit, 1=RTS always active
+	 * 01      TRS Timer Resolution, 1=512
+	 * 00      TLP Test Loop, 0 = no loop
+	 *
+	 * 1000 0010
+	 */
+	val = 0x82;
+
+	/* channel B RTS is used to enable AUXCLK driver on SP505 */
+	if (info->params.mode == MGSL_MODE_HDLC && info->params.clock_speed)
+		val |= BIT2;
+	write_reg(info, CHB + MODE, val);
+
+	/* CCR0
+	 *
+	 * 07      PU Power Up, 1=active, 0=power down
+	 * 06      MCE Master Clock Enable, 1=enabled
+	 * 05      Reserved, 0
+	 * 04..02  SC[2..0] Encoding
+	 * 01..00  SM[1..0] Serial Mode, 00=HDLC
+	 *
+	 * 11000000
+	 */
+	write_reg(info, CHB + CCR0, 0xc0);
+
+	/* CCR1
+	 *
+	 * 07      SFLG Shared Flag, 0 = disable shared flags
+	 * 06      GALP Go Active On Loop, 0 = not used
+	 * 05      GLP Go On Loop, 0 = not used
+	 * 04      ODS Output Driver Select, 1=TxD is push-pull output
+	 * 03      ITF Interframe Time Fill, 0=mark, 1=flag
+	 * 02..00  CM[2..0] Clock Mode
+	 *
+	 * 0001 0111
+	 */
+	write_reg(info, CHB + CCR1, 0x17);
+
+	/* CCR2 (Channel B)
+	 *
+	 * 07..06  BGR[9..8] Baud rate bits 9..8
+	 * 05      BDF Baud rate divisor factor, 0=1, 1=BGR value
+	 * 04      SSEL Clock source select, 1=submode b
+	 * 03      TOE 0=TxCLK is input, 1=TxCLK is output
+	 * 02      RWX Read/Write Exchange 0=disabled
+	 * 01      C32, CRC select, 0=CRC-16, 1=CRC-32
+	 * 00      DIV, data inversion 0=disabled, 1=enabled
+	 *
+	 * 0011 1000
+	 */
+	if (info->params.mode == MGSL_MODE_HDLC && info->params.clock_speed)
+		write_reg(info, CHB + CCR2, 0x38);
+	else
+		write_reg(info, CHB + CCR2, 0x30);
+
+	/* CCR4
+	 *
+	 * 07      MCK4 Master Clock Divide by 4, 1=enabled
+	 * 06      EBRG Enhanced Baud Rate Generator Mode, 1=enabled
+	 * 05      TST1 Test Pin, 0=normal operation
+	 * 04      ICD Ivert Carrier Detect, 1=enabled (active low)
+	 * 03..02  Reserved, must be 0
+	 * 01..00  RFT[1..0] RxFIFO Threshold 00=32 bytes
+	 *
+	 * 0101 0000
+	 */
+	write_reg(info, CHB + CCR4, 0x50);
+
+	/* if auxclk not enabled, set internal BRG so
+	 * CTS transitions can be detected (requires TxC)
+	 */
+	if (info->params.mode == MGSL_MODE_HDLC && info->params.clock_speed)
+		mgslpc_set_rate(info, CHB, info->params.clock_speed);
+	else
+		mgslpc_set_rate(info, CHB, 921600);
+}
+
+static void loopback_enable(MGSLPC_INFO *info)
+{
+	unsigned char val;
+
+	/* CCR1:02..00  CM[2..0] Clock Mode = 111 (clock mode 7) */
+	val = read_reg(info, CHA + CCR1) | (BIT2 | BIT1 | BIT0);
+	write_reg(info, CHA + CCR1, val);
+
+	/* CCR2:04 SSEL Clock source select, 1=submode b */
+	val = read_reg(info, CHA + CCR2) | (BIT4 | BIT5);
+	write_reg(info, CHA + CCR2, val);
+
+	/* set LinkSpeed if available, otherwise default to 2Mbps */
+	if (info->params.clock_speed)
+		mgslpc_set_rate(info, CHA, info->params.clock_speed);
+	else
+		mgslpc_set_rate(info, CHA, 1843200);
+
+	/* MODE:00 TLP Test Loop, 1=loopback enabled */
+	val = read_reg(info, CHA + MODE) | BIT0;
+	write_reg(info, CHA + MODE, val);
+}
+
+static void hdlc_mode(MGSLPC_INFO *info)
+{
+	unsigned char val;
+	unsigned char clkmode, clksubmode;
+
+	/* disable all interrupts */
+	irq_disable(info, CHA, 0xffff);
+	irq_disable(info, CHB, 0xffff);
+	port_irq_disable(info, 0xff);
+
+	/* assume clock mode 0a, rcv=RxC xmt=TxC */
+	clkmode = clksubmode = 0;
+	if (info->params.flags & HDLC_FLAG_RXC_DPLL
+	    && info->params.flags & HDLC_FLAG_TXC_DPLL) {
+		/* clock mode 7a, rcv = DPLL, xmt = DPLL */
+		clkmode = 7;
+	} else if (info->params.flags & HDLC_FLAG_RXC_BRG
+		 && info->params.flags & HDLC_FLAG_TXC_BRG) {
+		/* clock mode 7b, rcv = BRG, xmt = BRG */
+		clkmode = 7;
+		clksubmode = 1;
+	} else if (info->params.flags & HDLC_FLAG_RXC_DPLL) {
+		if (info->params.flags & HDLC_FLAG_TXC_BRG) {
+			/* clock mode 6b, rcv = DPLL, xmt = BRG/16 */
+			clkmode = 6;
+			clksubmode = 1;
+		} else {
+			/* clock mode 6a, rcv = DPLL, xmt = TxC */
+			clkmode = 6;
+		}
+	} else if (info->params.flags & HDLC_FLAG_TXC_BRG) {
+		/* clock mode 0b, rcv = RxC, xmt = BRG */
+		clksubmode = 1;
+	}
+
+	/* MODE
+	 *
+	 * 07..06  MDS[1..0] 10 = transparent HDLC mode
+	 * 05      ADM Address Mode, 0 = no addr recognition
+	 * 04      TMD Timer Mode, 0 = external
+	 * 03      RAC Receiver Active, 0 = inactive
+	 * 02      RTS 0=RTS active during xmit, 1=RTS always active
+	 * 01      TRS Timer Resolution, 1=512
+	 * 00      TLP Test Loop, 0 = no loop
+	 *
+	 * 1000 0010
+	 */
+	val = 0x82;
+	if (info->params.loopback)
+		val |= BIT0;
+
+	/* preserve RTS state */
+	if (info->serial_signals & SerialSignal_RTS)
+		val |= BIT2;
+	write_reg(info, CHA + MODE, val);
+
+	/* CCR0
+	 *
+	 * 07      PU Power Up, 1=active, 0=power down
+	 * 06      MCE Master Clock Enable, 1=enabled
+	 * 05      Reserved, 0
+	 * 04..02  SC[2..0] Encoding
+	 * 01..00  SM[1..0] Serial Mode, 00=HDLC
+	 *
+	 * 11000000
+	 */
+	val = 0xc0;
+	switch (info->params.encoding)
+	{
+	case HDLC_ENCODING_NRZI:
+		val |= BIT3;
+		break;
+	case HDLC_ENCODING_BIPHASE_SPACE:
+		val |= BIT4;
+		break;		// FM0
+	case HDLC_ENCODING_BIPHASE_MARK:
+		val |= BIT4 | BIT2;
+		break;		// FM1
+	case HDLC_ENCODING_BIPHASE_LEVEL:
+		val |= BIT4 | BIT3;
+		break;		// Manchester
+	}
+	write_reg(info, CHA + CCR0, val);
+
+	/* CCR1
+	 *
+	 * 07      SFLG Shared Flag, 0 = disable shared flags
+	 * 06      GALP Go Active On Loop, 0 = not used
+	 * 05      GLP Go On Loop, 0 = not used
+	 * 04      ODS Output Driver Select, 1=TxD is push-pull output
+	 * 03      ITF Interframe Time Fill, 0=mark, 1=flag
+	 * 02..00  CM[2..0] Clock Mode
+	 *
+	 * 0001 0000
+	 */
+	val = 0x10 + clkmode;
+	write_reg(info, CHA + CCR1, val);
+
+	/* CCR2
+	 *
+	 * 07..06  BGR[9..8] Baud rate bits 9..8
+	 * 05      BDF Baud rate divisor factor, 0=1, 1=BGR value
+	 * 04      SSEL Clock source select, 1=submode b
+	 * 03      TOE 0=TxCLK is input, 0=TxCLK is input
+	 * 02      RWX Read/Write Exchange 0=disabled
+	 * 01      C32, CRC select, 0=CRC-16, 1=CRC-32
+	 * 00      DIV, data inversion 0=disabled, 1=enabled
+	 *
+	 * 0000 0000
+	 */
+	val = 0x00;
+	if (clkmode == 2 || clkmode == 3 || clkmode == 6
+	    || clkmode == 7 || (clkmode == 0 && clksubmode == 1))
+		val |= BIT5;
+	if (clksubmode)
+		val |= BIT4;
+	if (info->params.crc_type == HDLC_CRC_32_CCITT)
+		val |= BIT1;
+	if (info->params.encoding == HDLC_ENCODING_NRZB)
+		val |= BIT0;
+	write_reg(info, CHA + CCR2, val);
+
+	/* CCR3
+	 *
+	 * 07..06  PRE[1..0] Preamble count 00=1, 01=2, 10=4, 11=8
+	 * 05      EPT Enable preamble transmission, 1=enabled
+	 * 04      RADD Receive address pushed to FIFO, 0=disabled
+	 * 03      CRL CRC Reset Level, 0=FFFF
+	 * 02      RCRC Rx CRC 0=On 1=Off
+	 * 01      TCRC Tx CRC 0=On 1=Off
+	 * 00      PSD DPLL Phase Shift Disable
+	 *
+	 * 0000 0000
+	 */
+	val = 0x00;
+	if (info->params.crc_type == HDLC_CRC_NONE)
+		val |= BIT2 | BIT1;
+	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
+		val |= BIT5;
+	switch (info->params.preamble_length)
+	{
+	case HDLC_PREAMBLE_LENGTH_16BITS:
+		val |= BIT6;
+		break;
+	case HDLC_PREAMBLE_LENGTH_32BITS:
+		val |= BIT6;
+		break;
+	case HDLC_PREAMBLE_LENGTH_64BITS:
+		val |= BIT7 | BIT6;
+		break;
+	}
+	write_reg(info, CHA + CCR3, val);
+
+	/* PRE - Preamble pattern */
+	val = 0;
+	switch (info->params.preamble)
+	{
+	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
+	case HDLC_PREAMBLE_PATTERN_10:    val = 0xaa; break;
+	case HDLC_PREAMBLE_PATTERN_01:    val = 0x55; break;
+	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
+	}
+	write_reg(info, CHA + PRE, val);
+
+	/* CCR4
+	 *
+	 * 07      MCK4 Master Clock Divide by 4, 1=enabled
+	 * 06      EBRG Enhanced Baud Rate Generator Mode, 1=enabled
+	 * 05      TST1 Test Pin, 0=normal operation
+	 * 04      ICD Ivert Carrier Detect, 1=enabled (active low)
+	 * 03..02  Reserved, must be 0
+	 * 01..00  RFT[1..0] RxFIFO Threshold 00=32 bytes
+	 *
+	 * 0101 0000
+	 */
+	val = 0x50;
+	write_reg(info, CHA + CCR4, val);
+	if (info->params.flags & HDLC_FLAG_RXC_DPLL)
+		mgslpc_set_rate(info, CHA, info->params.clock_speed * 16);
+	else
+		mgslpc_set_rate(info, CHA, info->params.clock_speed);
+
+	/* RLCR Receive length check register
+	 *
+	 * 7     1=enable receive length check
+	 * 6..0  Max frame length = (RL + 1) * 32
+	 */
+	write_reg(info, CHA + RLCR, 0);
+
+	/* XBCH Transmit Byte Count High
+	 *
+	 * 07      DMA mode, 0 = interrupt driven
+	 * 06      NRM, 0=ABM (ignored)
+	 * 05      CAS Carrier Auto Start
+	 * 04      XC Transmit Continuously (ignored)
+	 * 03..00  XBC[10..8] Transmit byte count bits 10..8
+	 *
+	 * 0000 0000
+	 */
+	val = 0x00;
+	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
+		val |= BIT5;
+	write_reg(info, CHA + XBCH, val);
+	enable_auxclk(info);
+	if (info->params.loopback || info->testing_irq)
+		loopback_enable(info);
+	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
+	{
+		irq_enable(info, CHB, IRQ_CTS);
+		/* PVR[3] 1=AUTO CTS active */
+		set_reg_bits(info, CHA + PVR, BIT3);
+	} else
+		clear_reg_bits(info, CHA + PVR, BIT3);
+
+	irq_enable(info, CHA,
+			 IRQ_RXEOM | IRQ_RXFIFO | IRQ_ALLSENT |
+			 IRQ_UNDERRUN | IRQ_TXFIFO);
+	issue_command(info, CHA, CMD_TXRESET + CMD_RXRESET);
+	wait_command_complete(info, CHA);
+	read_reg16(info, CHA + ISR);	/* clear pending IRQs */
+
+	/* Master clock mode enabled above to allow reset commands
+	 * to complete even if no data clocks are present.
+	 *
+	 * Disable master clock mode for normal communications because
+	 * V3.2 of the ESCC2 has a bug that prevents the transmit all sent
+	 * IRQ when in master clock mode.
+	 *
+	 * Leave master clock mode enabled for IRQ test because the
+	 * timer IRQ used by the test can only happen in master clock mode.
+	 */
+	if (!info->testing_irq)
+		clear_reg_bits(info, CHA + CCR0, BIT6);
+
+	tx_set_idle(info);
+
+	tx_stop(info);
+	rx_stop(info);
+}
+
+static void rx_stop(MGSLPC_INFO *info)
+{
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):rx_stop(%s)\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	/* MODE:03 RAC Receiver Active, 0=inactive */
+	clear_reg_bits(info, CHA + MODE, BIT3);
+
+	info->rx_enabled = false;
+	info->rx_overflow = false;
+}
+
+static void rx_start(MGSLPC_INFO *info)
+{
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):rx_start(%s)\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	rx_reset_buffers(info);
+	info->rx_enabled = false;
+	info->rx_overflow = false;
+
+	/* MODE:03 RAC Receiver Active, 1=active */
+	set_reg_bits(info, CHA + MODE, BIT3);
+
+	info->rx_enabled = true;
+}
+
+static void tx_start(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):tx_start(%s)\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	if (info->tx_count) {
+		/* If auto RTS enabled and RTS is inactive, then assert */
+		/* RTS and set a flag indicating that the driver should */
+		/* negate RTS when the transmission completes. */
+		info->drop_rts_on_tx_done = false;
+
+		if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
+			get_signals(info);
+			if (!(info->serial_signals & SerialSignal_RTS)) {
+				info->serial_signals |= SerialSignal_RTS;
+				set_signals(info);
+				info->drop_rts_on_tx_done = true;
+			}
+		}
+
+		if (info->params.mode == MGSL_MODE_ASYNC) {
+			if (!info->tx_active) {
+				info->tx_active = true;
+				tx_ready(info, tty);
+			}
+		} else {
+			info->tx_active = true;
+			tx_ready(info, tty);
+			mod_timer(&info->tx_timer, jiffies +
+					msecs_to_jiffies(5000));
+		}
+	}
+
+	if (!info->tx_enabled)
+		info->tx_enabled = true;
+}
+
+static void tx_stop(MGSLPC_INFO *info)
+{
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):tx_stop(%s)\n",
+			 __FILE__, __LINE__, info->device_name);
+
+	del_timer(&info->tx_timer);
+
+	info->tx_enabled = false;
+	info->tx_active = false;
+}
+
+/* Reset the adapter to a known state and prepare it for further use.
+ */
+static void reset_device(MGSLPC_INFO *info)
+{
+	/* power up both channels (set BIT7) */
+	write_reg(info, CHA + CCR0, 0x80);
+	write_reg(info, CHB + CCR0, 0x80);
+	write_reg(info, CHA + MODE, 0);
+	write_reg(info, CHB + MODE, 0);
+
+	/* disable all interrupts */
+	irq_disable(info, CHA, 0xffff);
+	irq_disable(info, CHB, 0xffff);
+	port_irq_disable(info, 0xff);
+
+	/* PCR Port Configuration Register
+	 *
+	 * 07..04  DEC[3..0] Serial I/F select outputs
+	 * 03      output, 1=AUTO CTS control enabled
+	 * 02      RI Ring Indicator input 0=active
+	 * 01      DSR input 0=active
+	 * 00      DTR output 0=active
+	 *
+	 * 0000 0110
+	 */
+	write_reg(info, PCR, 0x06);
+
+	/* PVR Port Value Register
+	 *
+	 * 07..04  DEC[3..0] Serial I/F select (0000=disabled)
+	 * 03      AUTO CTS output 1=enabled
+	 * 02      RI Ring Indicator input
+	 * 01      DSR input
+	 * 00      DTR output (1=inactive)
+	 *
+	 * 0000 0001
+	 */
+//	write_reg(info, PVR, PVR_DTR);
+
+	/* IPC Interrupt Port Configuration
+	 *
+	 * 07      VIS 1=Masked interrupts visible
+	 * 06..05  Reserved, 0
+	 * 04..03  SLA Slave address, 00 ignored
+	 * 02      CASM Cascading Mode, 1=daisy chain
+	 * 01..00  IC[1..0] Interrupt Config, 01=push-pull output, active low
+	 *
+	 * 0000 0101
+	 */
+	write_reg(info, IPC, 0x05);
+}
+
+static void async_mode(MGSLPC_INFO *info)
+{
+	unsigned char val;
+
+	/* disable all interrupts */
+	irq_disable(info, CHA, 0xffff);
+	irq_disable(info, CHB, 0xffff);
+	port_irq_disable(info, 0xff);
+
+	/* MODE
+	 *
+	 * 07      Reserved, 0
+	 * 06      FRTS RTS State, 0=active
+	 * 05      FCTS Flow Control on CTS
+	 * 04      FLON Flow Control Enable
+	 * 03      RAC Receiver Active, 0 = inactive
+	 * 02      RTS 0=Auto RTS, 1=manual RTS
+	 * 01      TRS Timer Resolution, 1=512
+	 * 00      TLP Test Loop, 0 = no loop
+	 *
+	 * 0000 0110
+	 */
+	val = 0x06;
+	if (info->params.loopback)
+		val |= BIT0;
+
+	/* preserve RTS state */
+	if (!(info->serial_signals & SerialSignal_RTS))
+		val |= BIT6;
+	write_reg(info, CHA + MODE, val);
+
+	/* CCR0
+	 *
+	 * 07      PU Power Up, 1=active, 0=power down
+	 * 06      MCE Master Clock Enable, 1=enabled
+	 * 05      Reserved, 0
+	 * 04..02  SC[2..0] Encoding, 000=NRZ
+	 * 01..00  SM[1..0] Serial Mode, 11=Async
+	 *
+	 * 1000 0011
+	 */
+	write_reg(info, CHA + CCR0, 0x83);
+
+	/* CCR1
+	 *
+	 * 07..05  Reserved, 0
+	 * 04      ODS Output Driver Select, 1=TxD is push-pull output
+	 * 03      BCR Bit Clock Rate, 1=16x
+	 * 02..00  CM[2..0] Clock Mode, 111=BRG
+	 *
+	 * 0001 1111
+	 */
+	write_reg(info, CHA + CCR1, 0x1f);
+
+	/* CCR2 (channel A)
+	 *
+	 * 07..06  BGR[9..8] Baud rate bits 9..8
+	 * 05      BDF Baud rate divisor factor, 0=1, 1=BGR value
+	 * 04      SSEL Clock source select, 1=submode b
+	 * 03      TOE 0=TxCLK is input, 0=TxCLK is input
+	 * 02      RWX Read/Write Exchange 0=disabled
+	 * 01      Reserved, 0
+	 * 00      DIV, data inversion 0=disabled, 1=enabled
+	 *
+	 * 0001 0000
+	 */
+	write_reg(info, CHA + CCR2, 0x10);
+
+	/* CCR3
+	 *
+	 * 07..01  Reserved, 0
+	 * 00      PSD DPLL Phase Shift Disable
+	 *
+	 * 0000 0000
+	 */
+	write_reg(info, CHA + CCR3, 0);
+
+	/* CCR4
+	 *
+	 * 07      MCK4 Master Clock Divide by 4, 1=enabled
+	 * 06      EBRG Enhanced Baud Rate Generator Mode, 1=enabled
+	 * 05      TST1 Test Pin, 0=normal operation
+	 * 04      ICD Ivert Carrier Detect, 1=enabled (active low)
+	 * 03..00  Reserved, must be 0
+	 *
+	 * 0101 0000
+	 */
+	write_reg(info, CHA + CCR4, 0x50);
+	mgslpc_set_rate(info, CHA, info->params.data_rate * 16);
+
+	/* DAFO Data Format
+	 *
+	 * 07      Reserved, 0
+	 * 06      XBRK transmit break, 0=normal operation
+	 * 05      Stop bits (0=1, 1=2)
+	 * 04..03  PAR[1..0] Parity (01=odd, 10=even)
+	 * 02      PAREN Parity Enable
+	 * 01..00  CHL[1..0] Character Length (00=8, 01=7)
+	 *
+	 */
+	val = 0x00;
+	if (info->params.data_bits != 8)
+		val |= BIT0;	/* 7 bits */
+	if (info->params.stop_bits != 1)
+		val |= BIT5;
+	if (info->params.parity != ASYNC_PARITY_NONE)
+	{
+		val |= BIT2;	/* Parity enable */
+		if (info->params.parity == ASYNC_PARITY_ODD)
+			val |= BIT3;
+		else
+			val |= BIT4;
+	}
+	write_reg(info, CHA + DAFO, val);
+
+	/* RFC Rx FIFO Control
+	 *
+	 * 07      Reserved, 0
+	 * 06      DPS, 1=parity bit not stored in data byte
+	 * 05      DXS, 0=all data stored in FIFO (including XON/XOFF)
+	 * 04      RFDF Rx FIFO Data Format, 1=status byte stored in FIFO
+	 * 03..02  RFTH[1..0], rx threshold, 11=16 status + 16 data byte
+	 * 01      Reserved, 0
+	 * 00      TCDE Terminate Char Detect Enable, 0=disabled
+	 *
+	 * 0101 1100
+	 */
+	write_reg(info, CHA + RFC, 0x5c);
+
+	/* RLCR Receive length check register
+	 *
+	 * Max frame length = (RL + 1) * 32
+	 */
+	write_reg(info, CHA + RLCR, 0);
+
+	/* XBCH Transmit Byte Count High
+	 *
+	 * 07      DMA mode, 0 = interrupt driven
+	 * 06      NRM, 0=ABM (ignored)
+	 * 05      CAS Carrier Auto Start
+	 * 04      XC Transmit Continuously (ignored)
+	 * 03..00  XBC[10..8] Transmit byte count bits 10..8
+	 *
+	 * 0000 0000
+	 */
+	val = 0x00;
+	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
+		val |= BIT5;
+	write_reg(info, CHA + XBCH, val);
+	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
+		irq_enable(info, CHA, IRQ_CTS);
+
+	/* MODE:03 RAC Receiver Active, 1=active */
+	set_reg_bits(info, CHA + MODE, BIT3);
+	enable_auxclk(info);
+	if (info->params.flags & HDLC_FLAG_AUTO_CTS) {
+		irq_enable(info, CHB, IRQ_CTS);
+		/* PVR[3] 1=AUTO CTS active */
+		set_reg_bits(info, CHA + PVR, BIT3);
+	} else
+		clear_reg_bits(info, CHA + PVR, BIT3);
+	irq_enable(info, CHA,
+			  IRQ_RXEOM | IRQ_RXFIFO | IRQ_BREAK_ON | IRQ_RXTIME |
+			  IRQ_ALLSENT | IRQ_TXFIFO);
+	issue_command(info, CHA, CMD_TXRESET + CMD_RXRESET);
+	wait_command_complete(info, CHA);
+	read_reg16(info, CHA + ISR);	/* clear pending IRQs */
+}
+
+/* Set the HDLC idle mode for the transmitter.
+ */
+static void tx_set_idle(MGSLPC_INFO *info)
+{
+	/* Note: ESCC2 only supports flags and one idle modes */
+	if (info->idle_mode == HDLC_TXIDLE_FLAGS)
+		set_reg_bits(info, CHA + CCR1, BIT3);
+	else
+		clear_reg_bits(info, CHA + CCR1, BIT3);
+}
+
+/* get state of the V24 status (input) signals.
+ */
+static void get_signals(MGSLPC_INFO *info)
+{
+	unsigned char status = 0;
+
+	/* preserve RTS and DTR */
+	info->serial_signals &= SerialSignal_RTS | SerialSignal_DTR;
+
+	if (read_reg(info, CHB + VSTR) & BIT7)
+		info->serial_signals |= SerialSignal_DCD;
+	if (read_reg(info, CHB + STAR) & BIT1)
+		info->serial_signals |= SerialSignal_CTS;
+
+	status = read_reg(info, CHA + PVR);
+	if (!(status & PVR_RI))
+		info->serial_signals |= SerialSignal_RI;
+	if (!(status & PVR_DSR))
+		info->serial_signals |= SerialSignal_DSR;
+}
+
+/* Set the state of RTS and DTR based on contents of
+ * serial_signals member of device extension.
+ */
+static void set_signals(MGSLPC_INFO *info)
+{
+	unsigned char val;
+
+	val = read_reg(info, CHA + MODE);
+	if (info->params.mode == MGSL_MODE_ASYNC) {
+		if (info->serial_signals & SerialSignal_RTS)
+			val &= ~BIT6;
+		else
+			val |= BIT6;
+	} else {
+		if (info->serial_signals & SerialSignal_RTS)
+			val |= BIT2;
+		else
+			val &= ~BIT2;
+	}
+	write_reg(info, CHA + MODE, val);
+
+	if (info->serial_signals & SerialSignal_DTR)
+		clear_reg_bits(info, CHA + PVR, PVR_DTR);
+	else
+		set_reg_bits(info, CHA + PVR, PVR_DTR);
+}
+
+static void rx_reset_buffers(MGSLPC_INFO *info)
+{
+	RXBUF *buf;
+	int i;
+
+	info->rx_put = 0;
+	info->rx_get = 0;
+	info->rx_frame_count = 0;
+	for (i=0 ; i < info->rx_buf_count ; i++) {
+		buf = (RXBUF*)(info->rx_buf + (i * info->rx_buf_size));
+		buf->status = buf->count = 0;
+	}
+}
+
+/* Attempt to return a received HDLC frame
+ * Only frames received without errors are returned.
+ *
+ * Returns true if frame returned, otherwise false
+ */
+static bool rx_get_frame(MGSLPC_INFO *info, struct tty_struct *tty)
+{
+	unsigned short status;
+	RXBUF *buf;
+	unsigned int framesize = 0;
+	unsigned long flags;
+	bool return_frame = false;
+
+	if (info->rx_frame_count == 0)
+		return false;
+
+	buf = (RXBUF*)(info->rx_buf + (info->rx_get * info->rx_buf_size));
+
+	status = buf->status;
+
+	/* 07  VFR  1=valid frame
+	 * 06  RDO  1=data overrun
+	 * 05  CRC  1=OK, 0=error
+	 * 04  RAB  1=frame aborted
+	 */
+	if ((status & 0xf0) != 0xA0) {
+		if (!(status & BIT7) || (status & BIT4))
+			info->icount.rxabort++;
+		else if (status & BIT6)
+			info->icount.rxover++;
+		else if (!(status & BIT5)) {
+			info->icount.rxcrc++;
+			if (info->params.crc_type & HDLC_CRC_RETURN_EX)
+				return_frame = true;
+		}
+		framesize = 0;
+#if SYNCLINK_GENERIC_HDLC
+		{
+			info->netdev->stats.rx_errors++;
+			info->netdev->stats.rx_frame_errors++;
+		}
+#endif
+	} else
+		return_frame = true;
+
+	if (return_frame)
+		framesize = buf->count;
+
+	if (debug_level >= DEBUG_LEVEL_BH)
+		printk("%s(%d):rx_get_frame(%s) status=%04X size=%d\n",
+			__FILE__, __LINE__, info->device_name, status, framesize);
+
+	if (debug_level >= DEBUG_LEVEL_DATA)
+		trace_block(info, buf->data, framesize, 0);
+
+	if (framesize) {
+		if ((info->params.crc_type & HDLC_CRC_RETURN_EX &&
+		      framesize+1 > info->max_frame_size) ||
+		    framesize > info->max_frame_size)
+			info->icount.rxlong++;
+		else {
+			if (status & BIT5)
+				info->icount.rxok++;
+
+			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
+				*(buf->data + framesize) = status & BIT5 ? RX_OK:RX_CRC_ERROR;
+				++framesize;
+			}
+
+#if SYNCLINK_GENERIC_HDLC
+			if (info->netcount)
+				hdlcdev_rx(info, buf->data, framesize);
+			else
+#endif
+				ldisc_receive_buf(tty, buf->data, info->flag_buf, framesize);
+		}
+	}
+
+	spin_lock_irqsave(&info->lock, flags);
+	buf->status = buf->count = 0;
+	info->rx_frame_count--;
+	info->rx_get++;
+	if (info->rx_get >= info->rx_buf_count)
+		info->rx_get = 0;
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	return true;
+}
+
+static bool register_test(MGSLPC_INFO *info)
+{
+	static unsigned char patterns[] =
+	    { 0x00, 0xff, 0xaa, 0x55, 0x69, 0x96, 0x0f };
+	static unsigned int count = ARRAY_SIZE(patterns);
+	unsigned int i;
+	bool rc = true;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+	reset_device(info);
+
+	for (i = 0; i < count; i++) {
+		write_reg(info, XAD1, patterns[i]);
+		write_reg(info, XAD2, patterns[(i + 1) % count]);
+		if ((read_reg(info, XAD1) != patterns[i]) ||
+		    (read_reg(info, XAD2) != patterns[(i + 1) % count])) {
+			rc = false;
+			break;
+		}
+	}
+
+	spin_unlock_irqrestore(&info->lock, flags);
+	return rc;
+}
+
+static bool irq_test(MGSLPC_INFO *info)
+{
+	unsigned long end_time;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+	reset_device(info);
+
+	info->testing_irq = true;
+	hdlc_mode(info);
+
+	info->irq_occurred = false;
+
+	/* init hdlc mode */
+
+	irq_enable(info, CHA, IRQ_TIMER);
+	write_reg(info, CHA + TIMR, 0);	/* 512 cycles */
+	issue_command(info, CHA, CMD_START_TIMER);
+
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	end_time=100;
+	while(end_time-- && !info->irq_occurred) {
+		msleep_interruptible(10);
+	}
+
+	info->testing_irq = false;
+
+	spin_lock_irqsave(&info->lock, flags);
+	reset_device(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	return info->irq_occurred;
+}
+
+static int adapter_test(MGSLPC_INFO *info)
+{
+	if (!register_test(info)) {
+		info->init_error = DiagStatus_AddressFailure;
+		printk("%s(%d):Register test failure for device %s Addr=%04X\n",
+			__FILE__, __LINE__, info->device_name, (unsigned short)(info->io_base));
+		return -ENODEV;
+	}
+
+	if (!irq_test(info)) {
+		info->init_error = DiagStatus_IrqFailure;
+		printk("%s(%d):Interrupt test failure for device %s IRQ=%d\n",
+			__FILE__, __LINE__, info->device_name, (unsigned short)(info->irq_level));
+		return -ENODEV;
+	}
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):device %s passed diagnostics\n",
+			__FILE__, __LINE__, info->device_name);
+	return 0;
+}
+
+static void trace_block(MGSLPC_INFO *info,const char* data, int count, int xmit)
+{
+	int i;
+	int linecount;
+	if (xmit)
+		printk("%s tx data:\n", info->device_name);
+	else
+		printk("%s rx data:\n", info->device_name);
+
+	while(count) {
+		if (count > 16)
+			linecount = 16;
+		else
+			linecount = count;
+
+		for(i=0;i<linecount;i++)
+			printk("%02X ", (unsigned char)data[i]);
+		for(;i<17;i++)
+			printk("   ");
+		for(i=0;i<linecount;i++) {
+			if (data[i]>=040 && data[i]<=0176)
+				printk("%c", data[i]);
+			else
+				printk(".");
+		}
+		printk("\n");
+
+		data  += linecount;
+		count -= linecount;
+	}
+}
+
+/* HDLC frame time out
+ * update stats and do tx completion processing
+ */
+static void tx_timeout(unsigned long context)
+{
+	MGSLPC_INFO *info = (MGSLPC_INFO*)context;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):tx_timeout(%s)\n",
+			__FILE__, __LINE__, info->device_name);
+	if (info->tx_active &&
+	    info->params.mode == MGSL_MODE_HDLC) {
+		info->icount.txtimeout++;
+	}
+	spin_lock_irqsave(&info->lock, flags);
+	info->tx_active = false;
+	info->tx_count = info->tx_put = info->tx_get = 0;
+
+	spin_unlock_irqrestore(&info->lock, flags);
+
+#if SYNCLINK_GENERIC_HDLC
+	if (info->netcount)
+		hdlcdev_tx_done(info);
+	else
+#endif
+	{
+		struct tty_struct *tty = tty_port_tty_get(&info->port);
+		bh_transmit(info, tty);
+		tty_kref_put(tty);
+	}
+}
+
+#if SYNCLINK_GENERIC_HDLC
+
+/**
+ * called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
+ * set encoding and frame check sequence (FCS) options
+ *
+ * dev       pointer to network device structure
+ * encoding  serial encoding setting
+ * parity    FCS setting
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
+			  unsigned short parity)
+{
+	MGSLPC_INFO *info = dev_to_port(dev);
+	struct tty_struct *tty;
+	unsigned char  new_encoding;
+	unsigned short new_crctype;
+
+	/* return error if TTY interface open */
+	if (info->port.count)
+		return -EBUSY;
+
+	switch (encoding)
+	{
+	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
+	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
+	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
+	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
+	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
+	default: return -EINVAL;
+	}
+
+	switch (parity)
+	{
+	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
+	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
+	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
+	default: return -EINVAL;
+	}
+
+	info->params.encoding = new_encoding;
+	info->params.crc_type = new_crctype;
+
+	/* if network interface up, reprogram hardware */
+	if (info->netcount) {
+		tty = tty_port_tty_get(&info->port);
+		mgslpc_program_hw(info, tty);
+		tty_kref_put(tty);
+	}
+
+	return 0;
+}
+
+/**
+ * called by generic HDLC layer to send frame
+ *
+ * skb  socket buffer containing HDLC frame
+ * dev  pointer to network device structure
+ */
+static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	MGSLPC_INFO *info = dev_to_port(dev);
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk(KERN_INFO "%s:hdlc_xmit(%s)\n", __FILE__, dev->name);
+
+	/* stop sending until this frame completes */
+	netif_stop_queue(dev);
+
+	/* copy data to device buffers */
+	skb_copy_from_linear_data(skb, info->tx_buf, skb->len);
+	info->tx_get = 0;
+	info->tx_put = info->tx_count = skb->len;
+
+	/* update network statistics */
+	dev->stats.tx_packets++;
+	dev->stats.tx_bytes += skb->len;
+
+	/* done with socket buffer, so free it */
+	dev_kfree_skb(skb);
+
+	/* save start time for transmit timeout detection */
+	dev->trans_start = jiffies;
+
+	/* start hardware transmitter if necessary */
+	spin_lock_irqsave(&info->lock, flags);
+	if (!info->tx_active) {
+		struct tty_struct *tty = tty_port_tty_get(&info->port);
+		tx_start(info, tty);
+		tty_kref_put(tty);
+	}
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	return NETDEV_TX_OK;
+}
+
+/**
+ * called by network layer when interface enabled
+ * claim resources and initialize hardware
+ *
+ * dev  pointer to network device structure
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_open(struct net_device *dev)
+{
+	MGSLPC_INFO *info = dev_to_port(dev);
+	struct tty_struct *tty;
+	int rc;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s:hdlcdev_open(%s)\n", __FILE__, dev->name);
+
+	/* generic HDLC layer open processing */
+	rc = hdlc_open(dev);
+	if (rc != 0)
+		return rc;
+
+	/* arbitrate between network and tty opens */
+	spin_lock_irqsave(&info->netlock, flags);
+	if (info->port.count != 0 || info->netcount != 0) {
+		printk(KERN_WARNING "%s: hdlc_open returning busy\n", dev->name);
+		spin_unlock_irqrestore(&info->netlock, flags);
+		return -EBUSY;
+	}
+	info->netcount=1;
+	spin_unlock_irqrestore(&info->netlock, flags);
+
+	tty = tty_port_tty_get(&info->port);
+	/* claim resources and init adapter */
+	rc = startup(info, tty);
+	if (rc != 0) {
+		tty_kref_put(tty);
+		spin_lock_irqsave(&info->netlock, flags);
+		info->netcount=0;
+		spin_unlock_irqrestore(&info->netlock, flags);
+		return rc;
+	}
+	/* assert RTS and DTR, apply hardware settings */
+	info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
+	mgslpc_program_hw(info, tty);
+	tty_kref_put(tty);
+
+	/* enable network layer transmit */
+	dev->trans_start = jiffies;
+	netif_start_queue(dev);
+
+	/* inform generic HDLC layer of current DCD status */
+	spin_lock_irqsave(&info->lock, flags);
+	get_signals(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+	if (info->serial_signals & SerialSignal_DCD)
+		netif_carrier_on(dev);
+	else
+		netif_carrier_off(dev);
+	return 0;
+}
+
+/**
+ * called by network layer when interface is disabled
+ * shutdown hardware and release resources
+ *
+ * dev  pointer to network device structure
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_close(struct net_device *dev)
+{
+	MGSLPC_INFO *info = dev_to_port(dev);
+	struct tty_struct *tty = tty_port_tty_get(&info->port);
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s:hdlcdev_close(%s)\n", __FILE__, dev->name);
+
+	netif_stop_queue(dev);
+
+	/* shutdown adapter and release resources */
+	shutdown(info, tty);
+	tty_kref_put(tty);
+	hdlc_close(dev);
+
+	spin_lock_irqsave(&info->netlock, flags);
+	info->netcount=0;
+	spin_unlock_irqrestore(&info->netlock, flags);
+
+	return 0;
+}
+
+/**
+ * called by network layer to process IOCTL call to network device
+ *
+ * dev  pointer to network device structure
+ * ifr  pointer to network interface request structure
+ * cmd  IOCTL command code
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	const size_t size = sizeof(sync_serial_settings);
+	sync_serial_settings new_line;
+	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
+	MGSLPC_INFO *info = dev_to_port(dev);
+	unsigned int flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s:hdlcdev_ioctl(%s)\n", __FILE__, dev->name);
+
+	/* return error if TTY interface open */
+	if (info->port.count)
+		return -EBUSY;
+
+	if (cmd != SIOCWANDEV)
+		return hdlc_ioctl(dev, ifr, cmd);
+
+	memset(&new_line, 0, size);
+
+	switch(ifr->ifr_settings.type) {
+	case IF_GET_IFACE: /* return current sync_serial_settings */
+
+		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
+		if (ifr->ifr_settings.size < size) {
+			ifr->ifr_settings.size = size; /* data size wanted */
+			return -ENOBUFS;
+		}
+
+		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
+
+		switch (flags){
+		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
+		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
+		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
+		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
+		default: new_line.clock_type = CLOCK_DEFAULT;
+		}
+
+		new_line.clock_rate = info->params.clock_speed;
+		new_line.loopback   = info->params.loopback ? 1:0;
+
+		if (copy_to_user(line, &new_line, size))
+			return -EFAULT;
+		return 0;
+
+	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
+
+		if(!capable(CAP_NET_ADMIN))
+			return -EPERM;
+		if (copy_from_user(&new_line, line, size))
+			return -EFAULT;
+
+		switch (new_line.clock_type)
+		{
+		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
+		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
+		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
+		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
+		case CLOCK_DEFAULT:  flags = info->params.flags &
+					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
+		default: return -EINVAL;
+		}
+
+		if (new_line.loopback != 0 && new_line.loopback != 1)
+			return -EINVAL;
+
+		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
+		info->params.flags |= flags;
+
+		info->params.loopback = new_line.loopback;
+
+		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
+			info->params.clock_speed = new_line.clock_rate;
+		else
+			info->params.clock_speed = 0;
+
+		/* if network interface up, reprogram hardware */
+		if (info->netcount) {
+			struct tty_struct *tty = tty_port_tty_get(&info->port);
+			mgslpc_program_hw(info, tty);
+			tty_kref_put(tty);
+		}
+		return 0;
+
+	default:
+		return hdlc_ioctl(dev, ifr, cmd);
+	}
+}
+
+/**
+ * called by network layer when transmit timeout is detected
+ *
+ * dev  pointer to network device structure
+ */
+static void hdlcdev_tx_timeout(struct net_device *dev)
+{
+	MGSLPC_INFO *info = dev_to_port(dev);
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("hdlcdev_tx_timeout(%s)\n", dev->name);
+
+	dev->stats.tx_errors++;
+	dev->stats.tx_aborted_errors++;
+
+	spin_lock_irqsave(&info->lock, flags);
+	tx_stop(info);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	netif_wake_queue(dev);
+}
+
+/**
+ * called by device driver when transmit completes
+ * reenable network layer transmit if stopped
+ *
+ * info  pointer to device instance information
+ */
+static void hdlcdev_tx_done(MGSLPC_INFO *info)
+{
+	if (netif_queue_stopped(info->netdev))
+		netif_wake_queue(info->netdev);
+}
+
+/**
+ * called by device driver when frame received
+ * pass frame to network layer
+ *
+ * info  pointer to device instance information
+ * buf   pointer to buffer contianing frame data
+ * size  count of data bytes in buf
+ */
+static void hdlcdev_rx(MGSLPC_INFO *info, char *buf, int size)
+{
+	struct sk_buff *skb = dev_alloc_skb(size);
+	struct net_device *dev = info->netdev;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("hdlcdev_rx(%s)\n", dev->name);
+
+	if (skb == NULL) {
+		printk(KERN_NOTICE "%s: can't alloc skb, dropping packet\n", dev->name);
+		dev->stats.rx_dropped++;
+		return;
+	}
+
+	memcpy(skb_put(skb, size), buf, size);
+
+	skb->protocol = hdlc_type_trans(skb, dev);
+
+	dev->stats.rx_packets++;
+	dev->stats.rx_bytes += size;
+
+	netif_rx(skb);
+}
+
+static const struct net_device_ops hdlcdev_ops = {
+	.ndo_open       = hdlcdev_open,
+	.ndo_stop       = hdlcdev_close,
+	.ndo_change_mtu = hdlc_change_mtu,
+	.ndo_start_xmit = hdlc_start_xmit,
+	.ndo_do_ioctl   = hdlcdev_ioctl,
+	.ndo_tx_timeout = hdlcdev_tx_timeout,
+};
+
+/**
+ * called by device driver when adding device instance
+ * do generic HDLC initialization
+ *
+ * info  pointer to device instance information
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_init(MGSLPC_INFO *info)
+{
+	int rc;
+	struct net_device *dev;
+	hdlc_device *hdlc;
+
+	/* allocate and initialize network and HDLC layer objects */
+
+	dev = alloc_hdlcdev(info);
+	if (dev == NULL) {
+		printk(KERN_ERR "%s:hdlc device allocation failure\n", __FILE__);
+		return -ENOMEM;
+	}
+
+	/* for network layer reporting purposes only */
+	dev->base_addr = info->io_base;
+	dev->irq       = info->irq_level;
+
+	/* network layer callbacks and settings */
+	dev->netdev_ops	    = &hdlcdev_ops;
+	dev->watchdog_timeo = 10 * HZ;
+	dev->tx_queue_len   = 50;
+
+	/* generic HDLC layer callbacks and settings */
+	hdlc         = dev_to_hdlc(dev);
+	hdlc->attach = hdlcdev_attach;
+	hdlc->xmit   = hdlcdev_xmit;
+
+	/* register objects with HDLC layer */
+	rc = register_hdlc_device(dev);
+	if (rc) {
+		printk(KERN_WARNING "%s:unable to register hdlc device\n", __FILE__);
+		free_netdev(dev);
+		return rc;
+	}
+
+	info->netdev = dev;
+	return 0;
+}
+
+/**
+ * called by device driver when removing device instance
+ * do generic HDLC cleanup
+ *
+ * info  pointer to device instance information
+ */
+static void hdlcdev_exit(MGSLPC_INFO *info)
+{
+	unregister_hdlc_device(info->netdev);
+	free_netdev(info->netdev);
+	info->netdev = NULL;
+}
+
+#endif /* CONFIG_HDLC */
+