Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 2630 insertions, 0 deletions

diff --git a/drivers/char/esp.c b/drivers/char/esp.c
new file mode 100644
index 000000000000..9f53d2fcc360
--- /dev/null
+++ b/drivers/char/esp.c
@@ -0,0 +1,2630 @@
+/*
+ *  esp.c - driver for Hayes ESP serial cards
+ *
+ *  --- Notices from serial.c, upon which this driver is based ---
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ *  Extensively rewritten by Theodore Ts'o, 8/16/92 -- 9/14/92.  Now
+ *  much more extensible to support other serial cards based on the
+ *  16450/16550A UART's.  Added support for the AST FourPort and the
+ *  Accent Async board.  
+ *
+ *  set_serial_info fixed to set the flags, custom divisor, and uart
+ * 	type fields.  Fix suggested by Michael K. Johnson 12/12/92.
+ *
+ *  11/95: TIOCMIWAIT, TIOCGICOUNT by Angelo Haritsis <ah@doc.ic.ac.uk>
+ *
+ *  03/96: Modularised by Angelo Haritsis <ah@doc.ic.ac.uk>
+ *
+ *  rs_set_termios fixed to look also for changes of the input
+ *      flags INPCK, BRKINT, PARMRK, IGNPAR and IGNBRK.
+ *                                            Bernd Anh�pl 05/17/96.
+ *
+ * --- End of notices from serial.c ---
+ *
+ * Support for the ESP serial card by Andrew J. Robinson
+ *     <arobinso@nyx.net> (Card detection routine taken from a patch
+ *     by Dennis J. Boylan).  Patches to allow use with 2.1.x contributed
+ *     by Chris Faylor.
+ *
+ * Most recent changes: (Andrew J. Robinson)
+ *   Support for PIO mode.  This allows the driver to work properly with
+ *     multiport cards.
+ *
+ * Arnaldo Carvalho de Melo <acme@conectiva.com.br> -
+ * several cleanups, use module_init/module_exit, etc
+ *
+ * This module exports the following rs232 io functions:
+ *
+ *	int espserial_init(void);
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/serialP.h>
+#include <linux/serial_reg.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/init.h>
+#include <linux/delay.h>
+
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/bitops.h>
+
+#include <asm/dma.h>
+#include <linux/slab.h>
+#include <asm/uaccess.h>
+
+#include <linux/hayesesp.h>
+
+#define NR_PORTS 64	/* maximum number of ports */
+#define NR_PRIMARY 8	/* maximum number of primary ports */
+#define REGION_SIZE 8   /* size of io region to request */
+
+/* The following variables can be set by giving module options */
+static int irq[NR_PRIMARY];	/* IRQ for each base port */
+static unsigned int divisor[NR_PRIMARY]; /* custom divisor for each port */
+static unsigned int dma = ESP_DMA_CHANNEL; /* DMA channel */
+static unsigned int rx_trigger = ESP_RX_TRIGGER;
+static unsigned int tx_trigger = ESP_TX_TRIGGER;
+static unsigned int flow_off = ESP_FLOW_OFF;
+static unsigned int flow_on = ESP_FLOW_ON;
+static unsigned int rx_timeout = ESP_RX_TMOUT;
+static unsigned int pio_threshold = ESP_PIO_THRESHOLD;
+
+MODULE_LICENSE("GPL");
+
+module_param_array(irq, int, NULL, 0);
+module_param_array(divisor, uint, NULL, 0);
+module_param(dma, uint, 0);
+module_param(rx_trigger, uint, 0);
+module_param(tx_trigger, uint, 0);
+module_param(flow_off, uint, 0);
+module_param(flow_on, uint, 0);
+module_param(rx_timeout, uint, 0);
+module_param(pio_threshold, uint, 0);
+
+/* END */
+
+static char *dma_buffer;
+static int dma_bytes;
+static struct esp_pio_buffer *free_pio_buf;
+
+#define DMA_BUFFER_SZ 1024
+
+#define WAKEUP_CHARS 1024
+
+static char serial_name[] __initdata = "ESP serial driver";
+static char serial_version[] __initdata = "2.2";
+
+static struct tty_driver *esp_driver;
+
+/* serial subtype definitions */
+#define SERIAL_TYPE_NORMAL	1
+
+/*
+ * Serial driver configuration section.  Here are the various options:
+ *
+ * SERIAL_PARANOIA_CHECK
+ * 		Check the magic number for the esp_structure where
+ * 		ever possible.
+ */
+
+#undef SERIAL_PARANOIA_CHECK
+#define SERIAL_DO_RESTART
+
+#undef SERIAL_DEBUG_INTR
+#undef SERIAL_DEBUG_OPEN
+#undef SERIAL_DEBUG_FLOW
+
+#if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
+#define DBG_CNT(s) printk("(%s): [%x] refc=%d, serc=%d, ttyc=%d -> %s\n", \
+ tty->name, (info->flags), serial_driver.refcount,info->count,tty->count,s)
+#else
+#define DBG_CNT(s)
+#endif
+
+static struct esp_struct *ports;
+
+static void change_speed(struct esp_struct *info);
+static void rs_wait_until_sent(struct tty_struct *, int);
+
+/*
+ * The ESP card has a clock rate of 14.7456 MHz (that is, 2**ESPC_SCALE
+ * times the normal 1.8432 Mhz clock of most serial boards).
+ */
+#define BASE_BAUD ((1843200 / 16) * (1 << ESPC_SCALE))
+
+/* Standard COM flags (except for COM4, because of the 8514 problem) */
+#define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
+
+/*
+ * tmp_buf is used as a temporary buffer by serial_write.  We need to
+ * lock it in case the memcpy_fromfs blocks while swapping in a page,
+ * and some other program tries to do a serial write at the same time.
+ * Since the lock will only come under contention when the system is
+ * swapping and available memory is low, it makes sense to share one
+ * buffer across all the serial ports, since it significantly saves
+ * memory if large numbers of serial ports are open.
+ */
+static unsigned char *tmp_buf;
+static DECLARE_MUTEX(tmp_buf_sem);
+
+static inline int serial_paranoia_check(struct esp_struct *info,
+					char *name, const char *routine)
+{
+#ifdef SERIAL_PARANOIA_CHECK
+	static const char badmagic[] = KERN_WARNING
+		"Warning: bad magic number for serial struct (%s) in %s\n";
+	static const char badinfo[] = KERN_WARNING
+		"Warning: null esp_struct for (%s) in %s\n";
+
+	if (!info) {
+		printk(badinfo, name, routine);
+		return 1;
+	}
+	if (info->magic != ESP_MAGIC) {
+		printk(badmagic, name, routine);
+		return 1;
+	}
+#endif
+	return 0;
+}
+
+static inline unsigned int serial_in(struct esp_struct *info, int offset)
+{
+	return inb(info->port + offset);
+}
+
+static inline void serial_out(struct esp_struct *info, int offset,
+			      unsigned char value)
+{
+	outb(value, info->port+offset);
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_stop() and rs_start()
+ *
+ * This routines are called before setting or resetting tty->stopped.
+ * They enable or disable transmitter interrupts, as necessary.
+ * ------------------------------------------------------------
+ */
+static void rs_stop(struct tty_struct *tty)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+
+	if (serial_paranoia_check(info, tty->name, "rs_stop"))
+		return;
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (info->IER & UART_IER_THRI) {
+		info->IER &= ~UART_IER_THRI;
+		serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+		serial_out(info, UART_ESI_CMD2, info->IER);
+	}
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+static void rs_start(struct tty_struct *tty)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (serial_paranoia_check(info, tty->name, "rs_start"))
+		return;
+	
+	spin_lock_irqsave(&info->lock, flags);
+	if (info->xmit_cnt && info->xmit_buf && !(info->IER & UART_IER_THRI)) {
+		info->IER |= UART_IER_THRI;
+		serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+		serial_out(info, UART_ESI_CMD2, info->IER);
+	}
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+/*
+ * ----------------------------------------------------------------------
+ *
+ * Here starts the interrupt handling routines.  All of the following
+ * subroutines are declared as inline and are folded into
+ * rs_interrupt().  They were separated out for readability's sake.
+ *
+ * Note: rs_interrupt() is a "fast" interrupt, which means that it
+ * runs with interrupts turned off.  People who may want to modify
+ * rs_interrupt() should try to keep the interrupt handler as fast as
+ * possible.  After you are done making modifications, it is not a bad
+ * idea to do:
+ * 
+ * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
+ *
+ * and look at the resulting assemble code in serial.s.
+ *
+ * 				- Ted Ts'o (tytso@mit.edu), 7-Mar-93
+ * -----------------------------------------------------------------------
+ */
+
+/*
+ * This routine is used by the interrupt handler to schedule
+ * processing in the software interrupt portion of the driver.
+ */
+static inline void rs_sched_event(struct esp_struct *info,
+				  int event)
+{
+	info->event |= 1 << event;
+	schedule_work(&info->tqueue);
+}
+
+static DEFINE_SPINLOCK(pio_lock);
+
+static inline struct esp_pio_buffer *get_pio_buffer(void)
+{
+	struct esp_pio_buffer *buf;
+	unsigned long flags;
+
+	spin_lock_irqsave(&pio_lock, flags);
+	if (free_pio_buf) {
+		buf = free_pio_buf;
+		free_pio_buf = buf->next;
+	} else {
+		buf = kmalloc(sizeof(struct esp_pio_buffer), GFP_ATOMIC);
+	}
+	spin_unlock_irqrestore(&pio_lock, flags);
+	return buf;
+}
+
+static inline void release_pio_buffer(struct esp_pio_buffer *buf)
+{
+	unsigned long flags;
+	spin_lock_irqsave(&pio_lock, flags);
+	buf->next = free_pio_buf;
+	free_pio_buf = buf;
+	spin_unlock_irqrestore(&pio_lock, flags);
+}
+
+static inline void receive_chars_pio(struct esp_struct *info, int num_bytes)
+{
+	struct tty_struct *tty = info->tty;
+	int i;
+	struct esp_pio_buffer *pio_buf;
+	struct esp_pio_buffer *err_buf;
+	unsigned char status_mask;
+
+	pio_buf = get_pio_buffer();
+
+	if (!pio_buf)
+		return;
+
+	err_buf = get_pio_buffer();
+
+	if (!err_buf) {
+		release_pio_buffer(pio_buf);
+		return;
+	}
+
+	status_mask = (info->read_status_mask >> 2) & 0x07;
+		
+	for (i = 0; i < num_bytes - 1; i += 2) {
+		*((unsigned short *)(pio_buf->data + i)) =
+			inw(info->port + UART_ESI_RX);
+		err_buf->data[i] = serial_in(info, UART_ESI_RWS);
+		err_buf->data[i + 1] = (err_buf->data[i] >> 3) & status_mask;
+		err_buf->data[i] &= status_mask;
+	}
+
+	if (num_bytes & 0x0001) {
+		pio_buf->data[num_bytes - 1] = serial_in(info, UART_ESI_RX);
+		err_buf->data[num_bytes - 1] =
+			(serial_in(info, UART_ESI_RWS) >> 3) & status_mask;
+	}
+
+	/* make sure everything is still ok since interrupts were enabled */
+	tty = info->tty;
+
+	if (!tty) {
+		release_pio_buffer(pio_buf);
+		release_pio_buffer(err_buf);
+		info->stat_flags &= ~ESP_STAT_RX_TIMEOUT;
+		return;
+	}
+
+	status_mask = (info->ignore_status_mask >> 2) & 0x07;
+
+	for (i = 0; i < num_bytes; i++) {
+		if (!(err_buf->data[i] & status_mask)) {
+			*(tty->flip.char_buf_ptr++) = pio_buf->data[i];
+
+			if (err_buf->data[i] & 0x04) {
+				*(tty->flip.flag_buf_ptr++) = TTY_BREAK;
+
+				if (info->flags & ASYNC_SAK)
+					do_SAK(tty);
+			}
+			else if (err_buf->data[i] & 0x02)
+				*(tty->flip.flag_buf_ptr++) = TTY_FRAME;
+			else if (err_buf->data[i] & 0x01)
+				*(tty->flip.flag_buf_ptr++) = TTY_PARITY;
+			else
+				*(tty->flip.flag_buf_ptr++) = 0;
+		
+			tty->flip.count++;
+		}
+	}
+
+	schedule_delayed_work(&tty->flip.work, 1);
+
+	info->stat_flags &= ~ESP_STAT_RX_TIMEOUT;
+	release_pio_buffer(pio_buf);
+	release_pio_buffer(err_buf);
+}
+
+static inline void receive_chars_dma(struct esp_struct *info, int num_bytes)
+{
+	unsigned long flags;
+	info->stat_flags &= ~ESP_STAT_RX_TIMEOUT;
+	dma_bytes = num_bytes;
+	info->stat_flags |= ESP_STAT_DMA_RX;
+	
+	flags=claim_dma_lock();
+        disable_dma(dma);
+        clear_dma_ff(dma);
+        set_dma_mode(dma, DMA_MODE_READ);
+        set_dma_addr(dma, isa_virt_to_bus(dma_buffer));
+        set_dma_count(dma, dma_bytes);
+        enable_dma(dma);
+        release_dma_lock(flags);
+        
+        serial_out(info, UART_ESI_CMD1, ESI_START_DMA_RX);
+}
+
+static inline void receive_chars_dma_done(struct esp_struct *info,
+					    int status)
+{
+	struct tty_struct *tty = info->tty;
+	int num_bytes;
+	unsigned long flags;
+	
+	
+	flags=claim_dma_lock();
+	disable_dma(dma);
+	clear_dma_ff(dma);
+
+	info->stat_flags &= ~ESP_STAT_DMA_RX;
+	num_bytes = dma_bytes - get_dma_residue(dma);
+	release_dma_lock(flags);
+	
+	info->icount.rx += num_bytes;
+
+	memcpy(tty->flip.char_buf_ptr, dma_buffer, num_bytes);
+	tty->flip.char_buf_ptr += num_bytes;
+	tty->flip.count += num_bytes;
+	memset(tty->flip.flag_buf_ptr, 0, num_bytes);
+	tty->flip.flag_buf_ptr += num_bytes;
+
+	if (num_bytes > 0) {
+		tty->flip.flag_buf_ptr--;
+
+		status &= (0x1c & info->read_status_mask);
+
+		if (status & info->ignore_status_mask) {
+			tty->flip.count--;
+			tty->flip.char_buf_ptr--;
+			tty->flip.flag_buf_ptr--;
+		} else if (status & 0x10) {
+			*tty->flip.flag_buf_ptr = TTY_BREAK;
+			(info->icount.brk)++;
+			if (info->flags & ASYNC_SAK)
+				do_SAK(tty);
+		} else if (status & 0x08) {
+			*tty->flip.flag_buf_ptr = TTY_FRAME;
+			(info->icount.frame)++;
+		}
+		else if (status & 0x04) {
+			*tty->flip.flag_buf_ptr = TTY_PARITY;
+			(info->icount.parity)++;
+		}
+
+		tty->flip.flag_buf_ptr++;
+		
+		schedule_delayed_work(&tty->flip.work, 1);
+	}
+
+	if (dma_bytes != num_bytes) {
+		num_bytes = dma_bytes - num_bytes;
+		dma_bytes = 0;
+		receive_chars_dma(info, num_bytes);
+	} else
+		dma_bytes = 0;
+}
+
+/* Caller must hold info->lock */
+
+static inline void transmit_chars_pio(struct esp_struct *info,
+					int space_avail)
+{
+	int i;
+	struct esp_pio_buffer *pio_buf;
+
+	pio_buf = get_pio_buffer();
+
+	if (!pio_buf)
+		return;
+
+	while (space_avail && info->xmit_cnt) {
+		if (info->xmit_tail + space_avail <= ESP_XMIT_SIZE) {
+			memcpy(pio_buf->data,
+			       &(info->xmit_buf[info->xmit_tail]),
+			       space_avail);
+		} else {
+			i = ESP_XMIT_SIZE - info->xmit_tail;
+			memcpy(pio_buf->data,
+			       &(info->xmit_buf[info->xmit_tail]), i);
+			memcpy(&(pio_buf->data[i]), info->xmit_buf,
+			       space_avail - i);
+		}
+
+		info->xmit_cnt -= space_avail;
+		info->xmit_tail = (info->xmit_tail + space_avail) &
+			(ESP_XMIT_SIZE - 1);
+
+		for (i = 0; i < space_avail - 1; i += 2) {
+			outw(*((unsigned short *)(pio_buf->data + i)),
+			     info->port + UART_ESI_TX);
+		}
+
+		if (space_avail & 0x0001)
+			serial_out(info, UART_ESI_TX,
+				   pio_buf->data[space_avail - 1]);
+
+		if (info->xmit_cnt) {
+			serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
+			serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
+			space_avail = serial_in(info, UART_ESI_STAT1) << 8;
+			space_avail |= serial_in(info, UART_ESI_STAT2);
+
+			if (space_avail > info->xmit_cnt)
+				space_avail = info->xmit_cnt;
+		}
+	}
+
+	if (info->xmit_cnt < WAKEUP_CHARS) {
+		rs_sched_event(info, ESP_EVENT_WRITE_WAKEUP);
+
+#ifdef SERIAL_DEBUG_INTR
+		printk("THRE...");
+#endif
+
+		if (info->xmit_cnt <= 0) {
+			info->IER &= ~UART_IER_THRI;
+			serial_out(info, UART_ESI_CMD1,
+				   ESI_SET_SRV_MASK);
+			serial_out(info, UART_ESI_CMD2, info->IER);
+		}
+	}
+
+	release_pio_buffer(pio_buf);
+}
+
+/* Caller must hold info->lock */
+static inline void transmit_chars_dma(struct esp_struct *info, int num_bytes)
+{
+	unsigned long flags;
+	
+	dma_bytes = num_bytes;
+
+	if (info->xmit_tail + dma_bytes <= ESP_XMIT_SIZE) {
+		memcpy(dma_buffer, &(info->xmit_buf[info->xmit_tail]),
+		       dma_bytes);
+	} else {
+		int i = ESP_XMIT_SIZE - info->xmit_tail;
+		memcpy(dma_buffer, &(info->xmit_buf[info->xmit_tail]),
+			i);
+		memcpy(&(dma_buffer[i]), info->xmit_buf, dma_bytes - i);
+	}
+
+	info->xmit_cnt -= dma_bytes;
+	info->xmit_tail = (info->xmit_tail + dma_bytes) & (ESP_XMIT_SIZE - 1);
+
+	if (info->xmit_cnt < WAKEUP_CHARS) {
+		rs_sched_event(info, ESP_EVENT_WRITE_WAKEUP);
+
+#ifdef SERIAL_DEBUG_INTR
+		printk("THRE...");
+#endif
+
+		if (info->xmit_cnt <= 0) {
+			info->IER &= ~UART_IER_THRI;
+			serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+			serial_out(info, UART_ESI_CMD2, info->IER);
+		}
+	}
+
+	info->stat_flags |= ESP_STAT_DMA_TX;
+	
+	flags=claim_dma_lock();
+        disable_dma(dma);
+        clear_dma_ff(dma);
+        set_dma_mode(dma, DMA_MODE_WRITE);
+        set_dma_addr(dma, isa_virt_to_bus(dma_buffer));
+        set_dma_count(dma, dma_bytes);
+        enable_dma(dma);
+        release_dma_lock(flags);
+        
+        serial_out(info, UART_ESI_CMD1, ESI_START_DMA_TX);
+}
+
+static inline void transmit_chars_dma_done(struct esp_struct *info)
+{
+	int num_bytes;
+	unsigned long flags;
+	
+
+	flags=claim_dma_lock();
+	disable_dma(dma);
+	clear_dma_ff(dma);
+
+	num_bytes = dma_bytes - get_dma_residue(dma);
+	info->icount.tx += dma_bytes;
+	release_dma_lock(flags);
+
+	if (dma_bytes != num_bytes) {
+		dma_bytes -= num_bytes;
+		memmove(dma_buffer, dma_buffer + num_bytes, dma_bytes);
+		
+		flags=claim_dma_lock();
+        	disable_dma(dma);
+        	clear_dma_ff(dma);
+        	set_dma_mode(dma, DMA_MODE_WRITE);
+        	set_dma_addr(dma, isa_virt_to_bus(dma_buffer));
+        	set_dma_count(dma, dma_bytes);
+        	enable_dma(dma);
+        	release_dma_lock(flags);
+        	
+        	serial_out(info, UART_ESI_CMD1, ESI_START_DMA_TX);
+	} else {
+		dma_bytes = 0;
+		info->stat_flags &= ~ESP_STAT_DMA_TX;
+	}
+}
+
+static inline void check_modem_status(struct esp_struct *info)
+{
+	int	status;
+	
+	serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
+	status = serial_in(info, UART_ESI_STAT2);
+
+	if (status & UART_MSR_ANY_DELTA) {
+		/* update input line counters */
+		if (status & UART_MSR_TERI)
+			info->icount.rng++;
+		if (status & UART_MSR_DDSR)
+			info->icount.dsr++;
+		if (status & UART_MSR_DDCD)
+			info->icount.dcd++;
+		if (status & UART_MSR_DCTS)
+			info->icount.cts++;
+		wake_up_interruptible(&info->delta_msr_wait);
+	}
+
+	if ((info->flags & ASYNC_CHECK_CD) && (status & UART_MSR_DDCD)) {
+#if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
+		printk("ttys%d CD now %s...", info->line,
+		       (status & UART_MSR_DCD) ? "on" : "off");
+#endif		
+		if (status & UART_MSR_DCD)
+			wake_up_interruptible(&info->open_wait);
+		else {
+#ifdef SERIAL_DEBUG_OPEN
+			printk("scheduling hangup...");
+#endif
+			schedule_work(&info->tqueue_hangup);
+		}
+	}
+}
+
+/*
+ * This is the serial driver's interrupt routine
+ */
+static irqreturn_t rs_interrupt_single(int irq, void *dev_id,
+					struct pt_regs *regs)
+{
+	struct esp_struct * info;
+	unsigned err_status;
+	unsigned int scratch;
+
+#ifdef SERIAL_DEBUG_INTR
+	printk("rs_interrupt_single(%d)...", irq);
+#endif
+	info = (struct esp_struct *)dev_id;
+	err_status = 0;
+	scratch = serial_in(info, UART_ESI_SID);
+
+	spin_lock(&info->lock);
+	
+	if (!info->tty) {
+		spin_unlock(&info->lock);
+		return IRQ_NONE;
+	}
+
+	if (scratch & 0x04) { /* error */
+		serial_out(info, UART_ESI_CMD1, ESI_GET_ERR_STAT);
+		err_status = serial_in(info, UART_ESI_STAT1);
+		serial_in(info, UART_ESI_STAT2);
+
+		if (err_status & 0x01)
+			info->stat_flags |= ESP_STAT_RX_TIMEOUT;
+
+		if (err_status & 0x20) /* UART status */
+			check_modem_status(info);
+
+		if (err_status & 0x80) /* Start break */
+			wake_up_interruptible(&info->break_wait);
+	}
+		
+	if ((scratch & 0x88) || /* DMA completed or timed out */
+	    (err_status & 0x1c) /* receive error */) {
+		if (info->stat_flags & ESP_STAT_DMA_RX)
+			receive_chars_dma_done(info, err_status);
+		else if (info->stat_flags & ESP_STAT_DMA_TX)
+			transmit_chars_dma_done(info);
+	}
+
+	if (!(info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) &&
+	    ((scratch & 0x01) || (info->stat_flags & ESP_STAT_RX_TIMEOUT)) &&
+	    (info->IER & UART_IER_RDI)) {
+		int num_bytes;
+
+		serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
+		serial_out(info, UART_ESI_CMD1, ESI_GET_RX_AVAIL);
+		num_bytes = serial_in(info, UART_ESI_STAT1) << 8;
+		num_bytes |= serial_in(info, UART_ESI_STAT2);
+
+		if (num_bytes > (TTY_FLIPBUF_SIZE - info->tty->flip.count))
+		  num_bytes = TTY_FLIPBUF_SIZE - info->tty->flip.count;
+
+		if (num_bytes) {
+			if (dma_bytes ||
+			    (info->stat_flags & ESP_STAT_USE_PIO) ||
+			    (num_bytes <= info->config.pio_threshold))
+				receive_chars_pio(info, num_bytes);
+			else
+				receive_chars_dma(info, num_bytes);
+		}
+	}
+	
+	if (!(info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) &&
+	    (scratch & 0x02) && (info->IER & UART_IER_THRI)) {
+		if ((info->xmit_cnt <= 0) || info->tty->stopped) {
+			info->IER &= ~UART_IER_THRI;
+			serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+			serial_out(info, UART_ESI_CMD2, info->IER);
+		} else {
+			int num_bytes;
+
+			serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
+			serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
+			num_bytes = serial_in(info, UART_ESI_STAT1) << 8;
+			num_bytes |= serial_in(info, UART_ESI_STAT2);
+
+			if (num_bytes > info->xmit_cnt)
+				num_bytes = info->xmit_cnt;
+
+			if (num_bytes) {
+				if (dma_bytes ||
+				    (info->stat_flags & ESP_STAT_USE_PIO) ||
+				    (num_bytes <= info->config.pio_threshold))
+					transmit_chars_pio(info, num_bytes);
+				else
+					transmit_chars_dma(info, num_bytes);
+			}
+		}
+	}
+
+	info->last_active = jiffies;
+
+#ifdef SERIAL_DEBUG_INTR
+	printk("end.\n");
+#endif
+	spin_unlock(&info->lock);
+	return IRQ_HANDLED;
+}
+
+/*
+ * -------------------------------------------------------------------
+ * Here ends the serial interrupt routines.
+ * -------------------------------------------------------------------
+ */
+
+static void do_softint(void *private_)
+{
+	struct esp_struct	*info = (struct esp_struct *) private_;
+	struct tty_struct	*tty;
+	
+	tty = info->tty;
+	if (!tty)
+		return;
+
+	if (test_and_clear_bit(ESP_EVENT_WRITE_WAKEUP, &info->event)) {
+		tty_wakeup(tty);
+	}
+}
+
+/*
+ * This routine is called from the scheduler tqueue when the interrupt
+ * routine has signalled that a hangup has occurred.  The path of
+ * hangup processing is:
+ *
+ * 	serial interrupt routine -> (scheduler tqueue) ->
+ * 	do_serial_hangup() -> tty->hangup() -> esp_hangup()
+ * 
+ */
+static void do_serial_hangup(void *private_)
+{
+	struct esp_struct	*info = (struct esp_struct *) private_;
+	struct tty_struct	*tty;
+	
+	tty = info->tty;
+	if (tty)
+		tty_hangup(tty);
+}
+
+/*
+ * ---------------------------------------------------------------
+ * Low level utility subroutines for the serial driver:  routines to
+ * figure out the appropriate timeout for an interrupt chain, routines
+ * to initialize and startup a serial port, and routines to shutdown a
+ * serial port.  Useful stuff like that.
+ *
+ * Caller should hold lock
+ * ---------------------------------------------------------------
+ */
+
+static inline void esp_basic_init(struct esp_struct * info)
+{
+	/* put ESPC in enhanced mode */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_MODE);
+	
+	if (info->stat_flags & ESP_STAT_NEVER_DMA)
+		serial_out(info, UART_ESI_CMD2, 0x01);
+	else
+		serial_out(info, UART_ESI_CMD2, 0x31);
+
+	/* disable interrupts for now */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+	serial_out(info, UART_ESI_CMD2, 0x00);
+
+	/* set interrupt and DMA channel */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_IRQ);
+
+	if (info->stat_flags & ESP_STAT_NEVER_DMA)
+		serial_out(info, UART_ESI_CMD2, 0x01);
+	else
+		serial_out(info, UART_ESI_CMD2, (dma << 4) | 0x01);
+
+	serial_out(info, UART_ESI_CMD1, ESI_SET_ENH_IRQ);
+
+	if (info->line % 8)	/* secondary port */
+		serial_out(info, UART_ESI_CMD2, 0x0d);	/* shared */
+	else if (info->irq == 9)
+		serial_out(info, UART_ESI_CMD2, 0x02);
+	else
+		serial_out(info, UART_ESI_CMD2, info->irq);
+
+	/* set error status mask (check this) */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_ERR_MASK);
+
+	if (info->stat_flags & ESP_STAT_NEVER_DMA)
+		serial_out(info, UART_ESI_CMD2, 0xa1);
+	else
+		serial_out(info, UART_ESI_CMD2, 0xbd);
+
+	serial_out(info, UART_ESI_CMD2, 0x00);
+
+	/* set DMA timeout */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_DMA_TMOUT);
+	serial_out(info, UART_ESI_CMD2, 0xff);
+
+	/* set FIFO trigger levels */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_TRIGGER);
+	serial_out(info, UART_ESI_CMD2, info->config.rx_trigger >> 8);
+	serial_out(info, UART_ESI_CMD2, info->config.rx_trigger);
+	serial_out(info, UART_ESI_CMD2, info->config.tx_trigger >> 8);
+	serial_out(info, UART_ESI_CMD2, info->config.tx_trigger);
+
+	/* Set clock scaling and wait states */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_PRESCALAR);
+	serial_out(info, UART_ESI_CMD2, 0x04 | ESPC_SCALE);
+
+	/* set reinterrupt pacing */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_REINTR);
+	serial_out(info, UART_ESI_CMD2, 0xff);
+}
+
+static int startup(struct esp_struct * info)
+{
+	unsigned long flags;
+	int	retval=0;
+        unsigned int num_chars;
+
+        spin_lock_irqsave(&info->lock, flags);
+
+	if (info->flags & ASYNC_INITIALIZED)
+		goto out;
+
+	if (!info->xmit_buf) {
+		info->xmit_buf = (unsigned char *)get_zeroed_page(GFP_ATOMIC);
+		retval = -ENOMEM;
+		if (!info->xmit_buf)
+			goto out;
+	}
+
+#ifdef SERIAL_DEBUG_OPEN
+	printk("starting up ttys%d (irq %d)...", info->line, info->irq);
+#endif
+
+	/* Flush the RX buffer.  Using the ESI flush command may cause */
+	/* wild interrupts, so read all the data instead. */
+
+	serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
+	serial_out(info, UART_ESI_CMD1, ESI_GET_RX_AVAIL);
+	num_chars = serial_in(info, UART_ESI_STAT1) << 8;
+	num_chars |= serial_in(info, UART_ESI_STAT2);
+
+	while (num_chars > 1) {
+		inw(info->port + UART_ESI_RX);
+		num_chars -= 2;
+	}
+
+	if (num_chars)
+		serial_in(info, UART_ESI_RX);
+
+	/* set receive character timeout */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
+	serial_out(info, UART_ESI_CMD2, info->config.rx_timeout);
+
+	/* clear all flags except the "never DMA" flag */
+	info->stat_flags &= ESP_STAT_NEVER_DMA;
+
+	if (info->stat_flags & ESP_STAT_NEVER_DMA)
+		info->stat_flags |= ESP_STAT_USE_PIO;
+
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	/*
+	 * Allocate the IRQ
+	 */
+
+	retval = request_irq(info->irq, rs_interrupt_single, SA_SHIRQ,
+			     "esp serial", info);
+
+	if (retval) {
+		if (capable(CAP_SYS_ADMIN)) {
+			if (info->tty)
+				set_bit(TTY_IO_ERROR,
+					&info->tty->flags);
+			retval = 0;
+		}
+		goto out_unlocked;
+	}
+
+	if (!(info->stat_flags & ESP_STAT_USE_PIO) && !dma_buffer) {
+		dma_buffer = (char *)__get_dma_pages(
+			GFP_KERNEL, get_order(DMA_BUFFER_SZ));
+
+		/* use PIO mode if DMA buf/chan cannot be allocated */
+		if (!dma_buffer)
+			info->stat_flags |= ESP_STAT_USE_PIO;
+		else if (request_dma(dma, "esp serial")) {
+			free_pages((unsigned long)dma_buffer,
+				   get_order(DMA_BUFFER_SZ));
+			dma_buffer = NULL;
+			info->stat_flags |= ESP_STAT_USE_PIO;
+		}
+			
+	}
+
+	info->MCR = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2;
+
+	spin_lock_irqsave(&info->lock, flags);
+	serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
+	serial_out(info, UART_ESI_CMD2, UART_MCR);
+	serial_out(info, UART_ESI_CMD2, info->MCR);
+	
+	/*
+	 * Finally, enable interrupts
+	 */
+	/* info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI; */
+	info->IER = UART_IER_RLSI | UART_IER_RDI | UART_IER_DMA_TMOUT |
+			UART_IER_DMA_TC;
+	serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+	serial_out(info, UART_ESI_CMD2, info->IER);
+	
+	if (info->tty)
+		clear_bit(TTY_IO_ERROR, &info->tty->flags);
+	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	/*
+	 * Set up the tty->alt_speed kludge
+	 */
+	if (info->tty) {
+		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
+			info->tty->alt_speed = 57600;
+		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
+			info->tty->alt_speed = 115200;
+		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
+			info->tty->alt_speed = 230400;
+		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
+			info->tty->alt_speed = 460800;
+	}
+	
+	/*
+	 * set the speed of the serial port
+	 */
+	change_speed(info);
+	info->flags |= ASYNC_INITIALIZED;
+	return 0;
+
+out:
+	spin_unlock_irqrestore(&info->lock, flags);
+out_unlocked:
+	return retval;
+}
+
+/*
+ * This routine will shutdown a serial port; interrupts are disabled, and
+ * DTR is dropped if the hangup on close termio flag is on.
+ */
+static void shutdown(struct esp_struct * info)
+{
+	unsigned long	flags, f;
+
+	if (!(info->flags & ASYNC_INITIALIZED))
+		return;
+
+#ifdef SERIAL_DEBUG_OPEN
+	printk("Shutting down serial port %d (irq %d)....", info->line,
+	       info->irq);
+#endif
+	
+	spin_lock_irqsave(&info->lock, flags);
+	/*
+	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
+	 * here so the queue might never be waken up
+	 */
+	wake_up_interruptible(&info->delta_msr_wait);
+	wake_up_interruptible(&info->break_wait);
+
+	/* stop a DMA transfer on the port being closed */
+	/* DMA lock is higher priority always */
+	if (info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) {
+		f=claim_dma_lock();
+		disable_dma(dma);
+		clear_dma_ff(dma);
+		release_dma_lock(f);
+		
+		dma_bytes = 0;
+	}
+	
+	/*
+	 * Free the IRQ
+	 */
+	free_irq(info->irq, info);
+
+	if (dma_buffer) {
+		struct esp_struct *current_port = ports;
+
+		while (current_port) {
+			if ((current_port != info) &&
+			    (current_port->flags & ASYNC_INITIALIZED))
+				break;
+
+			current_port = current_port->next_port;
+		}
+
+		if (!current_port) {
+			free_dma(dma);
+			free_pages((unsigned long)dma_buffer,
+				   get_order(DMA_BUFFER_SZ));
+			dma_buffer = NULL;
+		}		
+	}
+
+	if (info->xmit_buf) {
+		free_page((unsigned long) info->xmit_buf);
+		info->xmit_buf = NULL;
+	}
+
+	info->IER = 0;
+	serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+	serial_out(info, UART_ESI_CMD2, 0x00);
+
+	if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
+		info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
+
+	info->MCR &= ~UART_MCR_OUT2;
+	serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
+	serial_out(info, UART_ESI_CMD2, UART_MCR);
+	serial_out(info, UART_ESI_CMD2, info->MCR);
+
+	if (info->tty)
+		set_bit(TTY_IO_ERROR, &info->tty->flags);
+	
+	info->flags &= ~ASYNC_INITIALIZED;
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+/*
+ * This routine is called to set the UART divisor registers to match
+ * the specified baud rate for a serial port.
+ */
+static void change_speed(struct esp_struct *info)
+{
+	unsigned short port;
+	int	quot = 0;
+	unsigned cflag,cval;
+	int	baud, bits;
+	unsigned char flow1 = 0, flow2 = 0;
+	unsigned long flags;
+
+	if (!info->tty || !info->tty->termios)
+		return;
+	cflag = info->tty->termios->c_cflag;
+	port = info->port;
+	
+	/* byte size and parity */
+	switch (cflag & CSIZE) {
+	      case CS5: cval = 0x00; bits = 7; break;
+	      case CS6: cval = 0x01; bits = 8; break;
+	      case CS7: cval = 0x02; bits = 9; break;
+	      case CS8: cval = 0x03; bits = 10; break;
+	      default:  cval = 0x00; bits = 7; break;
+	}
+	if (cflag & CSTOPB) {
+		cval |= 0x04;
+		bits++;
+	}
+	if (cflag & PARENB) {
+		cval |= UART_LCR_PARITY;
+		bits++;
+	}
+	if (!(cflag & PARODD))
+		cval |= UART_LCR_EPAR;
+#ifdef CMSPAR
+	if (cflag & CMSPAR)
+		cval |= UART_LCR_SPAR;
+#endif
+
+	baud = tty_get_baud_rate(info->tty);
+	if (baud == 38400 &&
+	    ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
+		quot = info->custom_divisor;
+	else {
+		if (baud == 134)
+			/* Special case since 134 is really 134.5 */
+			quot = (2*BASE_BAUD / 269);
+		else if (baud)
+			quot = BASE_BAUD / baud;
+	}
+	/* If the quotient is ever zero, default to 9600 bps */
+	if (!quot)
+		quot = BASE_BAUD / 9600;
+	
+	info->timeout = ((1024 * HZ * bits * quot) / BASE_BAUD) + (HZ / 50);
+
+	/* CTS flow control flag and modem status interrupts */
+	/* info->IER &= ~UART_IER_MSI; */
+	if (cflag & CRTSCTS) {
+		info->flags |= ASYNC_CTS_FLOW;
+		/* info->IER |= UART_IER_MSI; */
+		flow1 = 0x04;
+		flow2 = 0x10;
+	} else
+		info->flags &= ~ASYNC_CTS_FLOW;
+	if (cflag & CLOCAL)
+		info->flags &= ~ASYNC_CHECK_CD;
+	else {
+		info->flags |= ASYNC_CHECK_CD;
+		/* info->IER |= UART_IER_MSI; */
+	}
+
+	/*
+	 * Set up parity check flag
+	 */
+#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
+
+	info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+	if (I_INPCK(info->tty))
+		info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
+	if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
+		info->read_status_mask |= UART_LSR_BI;
+	
+	info->ignore_status_mask = 0;
+#if 0
+	/* This should be safe, but for some broken bits of hardware... */
+	if (I_IGNPAR(info->tty)) {
+		info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
+		info->read_status_mask |= UART_LSR_PE | UART_LSR_FE;
+	}
+#endif
+	if (I_IGNBRK(info->tty)) {
+		info->ignore_status_mask |= UART_LSR_BI;
+		info->read_status_mask |= UART_LSR_BI;
+		/*
+		 * If we're ignore parity and break indicators, ignore 
+		 * overruns too.  (For real raw support).
+		 */
+		if (I_IGNPAR(info->tty)) {
+			info->ignore_status_mask |= UART_LSR_OE | \
+				UART_LSR_PE | UART_LSR_FE;
+			info->read_status_mask |= UART_LSR_OE | \
+				UART_LSR_PE | UART_LSR_FE;
+		}
+	}
+
+	if (I_IXOFF(info->tty))
+		flow1 |= 0x81;
+
+	spin_lock_irqsave(&info->lock, flags);
+	/* set baud */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_BAUD);
+	serial_out(info, UART_ESI_CMD2, quot >> 8);
+	serial_out(info, UART_ESI_CMD2, quot & 0xff);
+
+	/* set data bits, parity, etc. */
+	serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
+	serial_out(info, UART_ESI_CMD2, UART_LCR);
+	serial_out(info, UART_ESI_CMD2, cval);
+
+	/* Enable flow control */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_CNTL);
+	serial_out(info, UART_ESI_CMD2, flow1);
+	serial_out(info, UART_ESI_CMD2, flow2);
+
+	/* set flow control characters (XON/XOFF only) */
+	if (I_IXOFF(info->tty)) {
+		serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_CHARS);
+		serial_out(info, UART_ESI_CMD2, START_CHAR(info->tty));
+		serial_out(info, UART_ESI_CMD2, STOP_CHAR(info->tty));
+		serial_out(info, UART_ESI_CMD2, 0x10);
+		serial_out(info, UART_ESI_CMD2, 0x21);
+		switch (cflag & CSIZE) {
+			case CS5:
+				serial_out(info, UART_ESI_CMD2, 0x1f);
+				break;
+			case CS6:
+				serial_out(info, UART_ESI_CMD2, 0x3f);
+				break;
+			case CS7:
+			case CS8:
+				serial_out(info, UART_ESI_CMD2, 0x7f);
+				break;
+			default:
+				serial_out(info, UART_ESI_CMD2, 0xff);
+				break;
+		}
+	}
+
+	/* Set high/low water */
+	serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_LVL);
+	serial_out(info, UART_ESI_CMD2, info->config.flow_off >> 8);
+	serial_out(info, UART_ESI_CMD2, info->config.flow_off);
+	serial_out(info, UART_ESI_CMD2, info->config.flow_on >> 8);
+	serial_out(info, UART_ESI_CMD2, info->config.flow_on);
+
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+static void rs_put_char(struct tty_struct *tty, unsigned char ch)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+
+	if (serial_paranoia_check(info, tty->name, "rs_put_char"))
+		return;
+
+	if (!tty || !info->xmit_buf)
+		return;
+
+	spin_lock_irqsave(&info->lock, flags);
+	if (info->xmit_cnt < ESP_XMIT_SIZE - 1) {
+		info->xmit_buf[info->xmit_head++] = ch;
+		info->xmit_head &= ESP_XMIT_SIZE-1;
+		info->xmit_cnt++;
+	}
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+static void rs_flush_chars(struct tty_struct *tty)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+				
+	if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
+		return;
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	if (info->xmit_cnt <= 0 || tty->stopped || !info->xmit_buf)
+		goto out;
+
+	if (!(info->IER & UART_IER_THRI)) {
+		info->IER |= UART_IER_THRI;
+		serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+		serial_out(info, UART_ESI_CMD2, info->IER);
+	}
+out:
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+static int rs_write(struct tty_struct * tty,
+		    const unsigned char *buf, int count)
+{
+	int	c, t, ret = 0;
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+
+	if (serial_paranoia_check(info, tty->name, "rs_write"))
+		return 0;
+
+	if (!tty || !info->xmit_buf || !tmp_buf)
+		return 0;
+	    
+	while (1) {
+		/* Thanks to R. Wolff for suggesting how to do this with */
+		/* interrupts enabled */
+
+		c = count;
+		t = ESP_XMIT_SIZE - info->xmit_cnt - 1;
+		
+		if (t < c)
+			c = t;
+
+		t = ESP_XMIT_SIZE - info->xmit_head;
+		
+		if (t < c)
+			c = t;
+
+		if (c <= 0)
+			break;
+
+		memcpy(info->xmit_buf + info->xmit_head, buf, c);
+
+		info->xmit_head = (info->xmit_head + c) & (ESP_XMIT_SIZE-1);
+		info->xmit_cnt += c;
+		buf += c;
+		count -= c;
+		ret += c;
+	}
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	if (info->xmit_cnt && !tty->stopped && !(info->IER & UART_IER_THRI)) {
+		info->IER |= UART_IER_THRI;
+		serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+		serial_out(info, UART_ESI_CMD2, info->IER);
+	}
+
+	spin_unlock_irqrestore(&info->lock, flags);
+	return ret;
+}
+
+static int rs_write_room(struct tty_struct *tty)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	int	ret;
+	unsigned long flags;
+				
+	if (serial_paranoia_check(info, tty->name, "rs_write_room"))
+		return 0;
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	ret = ESP_XMIT_SIZE - info->xmit_cnt - 1;
+	if (ret < 0)
+		ret = 0;
+	spin_unlock_irqrestore(&info->lock, flags);
+	return ret;
+}
+
+static int rs_chars_in_buffer(struct tty_struct *tty)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+				
+	if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
+		return 0;
+	return info->xmit_cnt;
+}
+
+static void rs_flush_buffer(struct tty_struct *tty)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+				
+	if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
+		return;
+	spin_lock_irqsave(&info->lock, flags);
+	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+	spin_unlock_irqrestore(&info->lock, flags);
+	tty_wakeup(tty);
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_throttle()
+ * 
+ * This routine is called by the upper-layer tty layer to signal that
+ * incoming characters should be throttled.
+ * ------------------------------------------------------------
+ */
+static void rs_throttle(struct tty_struct * tty)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+#ifdef SERIAL_DEBUG_THROTTLE
+	char	buf[64];
+	
+	printk("throttle %s: %d....\n", tty_name(tty, buf),
+	       tty->ldisc.chars_in_buffer(tty));
+#endif
+
+	if (serial_paranoia_check(info, tty->name, "rs_throttle"))
+		return;
+
+	spin_lock_irqsave(&info->lock, flags);
+	info->IER &= ~UART_IER_RDI;
+	serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+	serial_out(info, UART_ESI_CMD2, info->IER);
+	serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
+	serial_out(info, UART_ESI_CMD2, 0x00);
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+static void rs_unthrottle(struct tty_struct * tty)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+#ifdef SERIAL_DEBUG_THROTTLE
+	char	buf[64];
+	
+	printk("unthrottle %s: %d....\n", tty_name(tty, buf),
+	       tty->ldisc.chars_in_buffer(tty));
+#endif
+
+	if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
+		return;
+	
+	spin_lock_irqsave(&info->lock, flags);
+	info->IER |= UART_IER_RDI;
+	serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+	serial_out(info, UART_ESI_CMD2, info->IER);
+	serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
+	serial_out(info, UART_ESI_CMD2, info->config.rx_timeout);
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_ioctl() and friends
+ * ------------------------------------------------------------
+ */
+
+static int get_serial_info(struct esp_struct * info,
+			   struct serial_struct __user *retinfo)
+{
+	struct serial_struct tmp;
+  
+	memset(&tmp, 0, sizeof(tmp));
+	tmp.type = PORT_16550A;
+	tmp.line = info->line;
+	tmp.port = info->port;
+	tmp.irq = info->irq;
+	tmp.flags = info->flags;
+	tmp.xmit_fifo_size = 1024;
+	tmp.baud_base = BASE_BAUD;
+	tmp.close_delay = info->close_delay;
+	tmp.closing_wait = info->closing_wait;
+	tmp.custom_divisor = info->custom_divisor;
+	tmp.hub6 = 0;
+	if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
+		return -EFAULT;
+	return 0;
+}
+
+static int get_esp_config(struct esp_struct * info,
+			  struct hayes_esp_config __user *retinfo)
+{
+	struct hayes_esp_config tmp;
+  
+	if (!retinfo)
+		return -EFAULT;
+
+	memset(&tmp, 0, sizeof(tmp));
+	tmp.rx_timeout = info->config.rx_timeout;
+	tmp.rx_trigger = info->config.rx_trigger;
+	tmp.tx_trigger = info->config.tx_trigger;
+	tmp.flow_off = info->config.flow_off;
+	tmp.flow_on = info->config.flow_on;
+	tmp.pio_threshold = info->config.pio_threshold;
+	tmp.dma_channel = (info->stat_flags & ESP_STAT_NEVER_DMA ? 0 : dma);
+
+	return copy_to_user(retinfo, &tmp, sizeof(*retinfo)) ? -EFAULT : 0;
+}
+
+static int set_serial_info(struct esp_struct * info,
+			   struct serial_struct __user *new_info)
+{
+	struct serial_struct new_serial;
+	struct esp_struct old_info;
+	unsigned int change_irq;
+	int retval = 0;
+	struct esp_struct *current_async;
+
+	if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
+		return -EFAULT;
+	old_info = *info;
+
+	if ((new_serial.type != PORT_16550A) ||
+	    (new_serial.hub6) ||
+	    (info->port != new_serial.port) ||
+	    (new_serial.baud_base != BASE_BAUD) ||
+	    (new_serial.irq > 15) ||
+	    (new_serial.irq < 2) ||
+	    (new_serial.irq == 6) ||
+	    (new_serial.irq == 8) ||
+	    (new_serial.irq == 13))
+		return -EINVAL;
+
+	change_irq = new_serial.irq != info->irq;
+
+	if (change_irq && (info->line % 8))
+		return -EINVAL;
+
+	if (!capable(CAP_SYS_ADMIN)) {
+		if (change_irq || 
+		    (new_serial.close_delay != info->close_delay) ||
+		    ((new_serial.flags & ~ASYNC_USR_MASK) !=
+		     (info->flags & ~ASYNC_USR_MASK)))
+			return -EPERM;
+		info->flags = ((info->flags & ~ASYNC_USR_MASK) |
+			       (new_serial.flags & ASYNC_USR_MASK));
+		info->custom_divisor = new_serial.custom_divisor;
+	} else {
+		if (new_serial.irq == 2)
+			new_serial.irq = 9;
+
+		if (change_irq) {
+			current_async = ports;
+
+			while (current_async) {
+				if ((current_async->line >= info->line) &&
+				    (current_async->line < (info->line + 8))) {
+					if (current_async == info) {
+						if (current_async->count > 1)
+							return -EBUSY;
+					} else if (current_async->count)
+						return -EBUSY;
+				}
+
+				current_async = current_async->next_port;
+			}
+		}
+
+		/*
+		 * OK, past this point, all the error checking has been done.
+		 * At this point, we start making changes.....
+		 */
+
+		info->flags = ((info->flags & ~ASYNC_FLAGS) |
+			       (new_serial.flags & ASYNC_FLAGS));
+		info->custom_divisor = new_serial.custom_divisor;
+		info->close_delay = new_serial.close_delay * HZ/100;
+		info->closing_wait = new_serial.closing_wait * HZ/100;
+
+		if (change_irq) {
+			/*
+			 * We need to shutdown the serial port at the old
+			 * port/irq combination.
+			 */
+			shutdown(info);
+
+			current_async = ports;
+
+			while (current_async) {
+				if ((current_async->line >= info->line) &&
+				    (current_async->line < (info->line + 8)))
+					current_async->irq = new_serial.irq;
+
+				current_async = current_async->next_port;
+			}
+
+			serial_out(info, UART_ESI_CMD1, ESI_SET_ENH_IRQ);
+			if (info->irq == 9)
+				serial_out(info, UART_ESI_CMD2, 0x02);
+			else
+				serial_out(info, UART_ESI_CMD2, info->irq);
+		}
+	}
+
+	if (info->flags & ASYNC_INITIALIZED) {
+		if (((old_info.flags & ASYNC_SPD_MASK) !=
+		     (info->flags & ASYNC_SPD_MASK)) ||
+		    (old_info.custom_divisor != info->custom_divisor)) {
+			if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
+				info->tty->alt_speed = 57600;
+			if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
+				info->tty->alt_speed = 115200;
+			if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
+				info->tty->alt_speed = 230400;
+			if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
+				info->tty->alt_speed = 460800;
+			change_speed(info);
+		}
+	} else
+		retval = startup(info);
+
+	return retval;
+}
+
+static int set_esp_config(struct esp_struct * info,
+			  struct hayes_esp_config __user * new_info)
+{
+	struct hayes_esp_config new_config;
+	unsigned int change_dma;
+	int retval = 0;
+	struct esp_struct *current_async;
+	unsigned long flags;
+
+	/* Perhaps a non-sysadmin user should be able to do some of these */
+	/* operations.  I haven't decided yet. */
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (copy_from_user(&new_config, new_info, sizeof(new_config)))
+		return -EFAULT;
+
+	if ((new_config.flow_on >= new_config.flow_off) ||
+	    (new_config.rx_trigger < 1) ||
+	    (new_config.tx_trigger < 1) ||
+	    (new_config.flow_off < 1) ||
+	    (new_config.flow_on < 1) ||
+	    (new_config.rx_trigger > 1023) ||
+	    (new_config.tx_trigger > 1023) ||
+	    (new_config.flow_off > 1023) ||
+	    (new_config.flow_on > 1023) ||
+	    (new_config.pio_threshold < 0) ||
+	    (new_config.pio_threshold > 1024))
+		return -EINVAL;
+
+	if ((new_config.dma_channel != 1) && (new_config.dma_channel != 3))
+		new_config.dma_channel = 0;
+
+	if (info->stat_flags & ESP_STAT_NEVER_DMA)
+		change_dma = new_config.dma_channel;
+	else
+		change_dma = (new_config.dma_channel != dma);
+
+	if (change_dma) {
+		if (new_config.dma_channel) {
+			/* PIO mode to DMA mode transition OR */
+			/* change current DMA channel */
+			
+			current_async = ports;
+
+			while (current_async) {
+				if (current_async == info) {
+					if (current_async->count > 1)
+						return -EBUSY;
+				} else if (current_async->count)
+					return -EBUSY;
+					
+				current_async =
+					current_async->next_port;
+			}
+
+			shutdown(info);
+			dma = new_config.dma_channel;
+			info->stat_flags &= ~ESP_STAT_NEVER_DMA;
+			
+                        /* all ports must use the same DMA channel */
+
+			spin_lock_irqsave(&info->lock, flags);
+			current_async = ports;
+
+			while (current_async) {
+				esp_basic_init(current_async);
+				current_async = current_async->next_port;
+			}
+			spin_unlock_irqrestore(&info->lock, flags);
+		} else {
+			/* DMA mode to PIO mode only */
+			
+			if (info->count > 1)
+				return -EBUSY;
+
+			shutdown(info);
+			spin_lock_irqsave(&info->lock, flags);
+			info->stat_flags |= ESP_STAT_NEVER_DMA;
+			esp_basic_init(info);
+			spin_unlock_irqrestore(&info->lock, flags);
+		}
+	}
+
+	info->config.pio_threshold = new_config.pio_threshold;
+
+	if ((new_config.flow_off != info->config.flow_off) ||
+	    (new_config.flow_on != info->config.flow_on)) {
+		unsigned long flags;
+
+		info->config.flow_off = new_config.flow_off;
+		info->config.flow_on = new_config.flow_on;
+
+		spin_lock_irqsave(&info->lock, flags);
+		serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_LVL);
+		serial_out(info, UART_ESI_CMD2, new_config.flow_off >> 8);
+		serial_out(info, UART_ESI_CMD2, new_config.flow_off);
+		serial_out(info, UART_ESI_CMD2, new_config.flow_on >> 8);
+		serial_out(info, UART_ESI_CMD2, new_config.flow_on);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+
+	if ((new_config.rx_trigger != info->config.rx_trigger) ||
+	    (new_config.tx_trigger != info->config.tx_trigger)) {
+		unsigned long flags;
+
+		info->config.rx_trigger = new_config.rx_trigger;
+		info->config.tx_trigger = new_config.tx_trigger;
+		spin_lock_irqsave(&info->lock, flags);
+		serial_out(info, UART_ESI_CMD1, ESI_SET_TRIGGER);
+		serial_out(info, UART_ESI_CMD2,
+			   new_config.rx_trigger >> 8);
+		serial_out(info, UART_ESI_CMD2, new_config.rx_trigger);
+		serial_out(info, UART_ESI_CMD2,
+			   new_config.tx_trigger >> 8);
+		serial_out(info, UART_ESI_CMD2, new_config.tx_trigger);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+
+	if (new_config.rx_timeout != info->config.rx_timeout) {
+		unsigned long flags;
+
+		info->config.rx_timeout = new_config.rx_timeout;
+		spin_lock_irqsave(&info->lock, flags);
+
+		if (info->IER & UART_IER_RDI) {
+			serial_out(info, UART_ESI_CMD1,
+				   ESI_SET_RX_TIMEOUT);
+			serial_out(info, UART_ESI_CMD2,
+				   new_config.rx_timeout);
+		}
+
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+
+	if (!(info->flags & ASYNC_INITIALIZED))
+		retval = startup(info);
+
+	return retval;
+}
+
+/*
+ * get_lsr_info - get line status register info
+ *
+ * Purpose: Let user call ioctl() to get info when the UART physically
+ * 	    is emptied.  On bus types like RS485, the transmitter must
+ * 	    release the bus after transmitting. This must be done when
+ * 	    the transmit shift register is empty, not be done when the
+ * 	    transmit holding register is empty.  This functionality
+ * 	    allows an RS485 driver to be written in user space. 
+ */
+static int get_lsr_info(struct esp_struct * info, unsigned int __user *value)
+{
+	unsigned char status;
+	unsigned int result;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock, flags);
+	serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
+	status = serial_in(info, UART_ESI_STAT1);
+	spin_unlock_irqrestore(&info->lock, flags);
+	result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
+	return put_user(result,value);
+}
+
+
+static int esp_tiocmget(struct tty_struct *tty, struct file *file)
+{
+	struct esp_struct * info = (struct esp_struct *)tty->driver_data;
+	unsigned char control, status;
+	unsigned long flags;
+
+	if (serial_paranoia_check(info, tty->name, __FUNCTION__))
+		return -ENODEV;
+	if (tty->flags & (1 << TTY_IO_ERROR))
+		return -EIO;
+
+	control = info->MCR;
+
+	spin_lock_irqsave(&info->lock, flags);
+	serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
+	status = serial_in(info, UART_ESI_STAT2);
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	return    ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
+		| ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
+		| ((status  & UART_MSR_DCD) ? TIOCM_CAR : 0)
+		| ((status  & UART_MSR_RI) ? TIOCM_RNG : 0)
+		| ((status  & UART_MSR_DSR) ? TIOCM_DSR : 0)
+		| ((status  & UART_MSR_CTS) ? TIOCM_CTS : 0);
+}
+
+static int esp_tiocmset(struct tty_struct *tty, struct file *file,
+			unsigned int set, unsigned int clear)
+{
+	struct esp_struct * info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+
+	if (serial_paranoia_check(info, tty->name, __FUNCTION__))
+		return -ENODEV;
+	if (tty->flags & (1 << TTY_IO_ERROR))
+		return -EIO;
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	if (set & TIOCM_RTS)
+		info->MCR |= UART_MCR_RTS;
+	if (set & TIOCM_DTR)
+		info->MCR |= UART_MCR_DTR;
+
+	if (clear & TIOCM_RTS)
+		info->MCR &= ~UART_MCR_RTS;
+	if (clear & TIOCM_DTR)
+		info->MCR &= ~UART_MCR_DTR;
+
+	serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
+	serial_out(info, UART_ESI_CMD2, UART_MCR);
+	serial_out(info, UART_ESI_CMD2, info->MCR);
+
+	spin_unlock_irqrestore(&info->lock, flags);
+	return 0;
+}
+
+/*
+ * rs_break() --- routine which turns the break handling on or off
+ */
+static void esp_break(struct tty_struct *tty, int break_state)
+{
+	struct esp_struct * info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (serial_paranoia_check(info, tty->name, "esp_break"))
+		return;
+
+	if (break_state == -1) {
+		spin_lock_irqsave(&info->lock, flags);
+		serial_out(info, UART_ESI_CMD1, ESI_ISSUE_BREAK);
+		serial_out(info, UART_ESI_CMD2, 0x01);
+		spin_unlock_irqrestore(&info->lock, flags);
+
+		/* FIXME - new style wait needed here */
+		interruptible_sleep_on(&info->break_wait);
+	} else {
+		spin_lock_irqsave(&info->lock, flags);
+		serial_out(info, UART_ESI_CMD1, ESI_ISSUE_BREAK);
+		serial_out(info, UART_ESI_CMD2, 0x00);
+		spin_unlock_irqrestore(&info->lock, flags);
+	}
+}
+
+static int rs_ioctl(struct tty_struct *tty, struct file * file,
+		    unsigned int cmd, unsigned long arg)
+{
+	struct esp_struct * info = (struct esp_struct *)tty->driver_data;
+	struct async_icount cprev, cnow;	/* kernel counter temps */
+	struct serial_icounter_struct __user *p_cuser;	/* user space */
+	void __user *argp = (void __user *)arg;
+	unsigned long flags;
+
+	if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
+		return -ENODEV;
+
+	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
+	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD)  &&
+	    (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT) &&
+	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT) &&
+	    (cmd != TIOCGHAYESESP) && (cmd != TIOCSHAYESESP)) {
+		if (tty->flags & (1 << TTY_IO_ERROR))
+		    return -EIO;
+	}
+	
+	switch (cmd) {
+		case TIOCGSERIAL:
+			return get_serial_info(info, argp);
+		case TIOCSSERIAL:
+			return set_serial_info(info, argp);
+		case TIOCSERCONFIG:
+			/* do not reconfigure after initial configuration */
+			return 0;
+
+		case TIOCSERGWILD:
+			return put_user(0L, (unsigned long __user *)argp);
+
+		case TIOCSERGETLSR: /* Get line status register */
+			    return get_lsr_info(info, argp);
+
+		case TIOCSERSWILD:
+			if (!capable(CAP_SYS_ADMIN))
+				return -EPERM;
+			return 0;
+
+		/*
+		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
+		 * - mask passed in arg for lines of interest
+ 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
+		 * Caller should use TIOCGICOUNT to see which one it was
+		 */
+		 case TIOCMIWAIT:
+			spin_lock_irqsave(&info->lock, flags);
+			cprev = info->icount;	/* note the counters on entry */
+			spin_unlock_irqrestore(&info->lock, flags);
+			while (1) {
+				/* FIXME: convert to new style wakeup */
+				interruptible_sleep_on(&info->delta_msr_wait);
+				/* see if a signal did it */
+				if (signal_pending(current))
+					return -ERESTARTSYS;
+				spin_lock_irqsave(&info->lock, flags);
+				cnow = info->icount;	/* atomic copy */
+				spin_unlock_irqrestore(&info->lock, flags);
+				if (cnow.rng == cprev.rng &&
+				    cnow.dsr == cprev.dsr && 
+				    cnow.dcd == cprev.dcd &&
+				    cnow.cts == cprev.cts)
+					return -EIO; /* no change => error */
+				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)) ) {
+					return 0;
+				}
+				cprev = cnow;
+			}
+			/* NOTREACHED */
+
+		/* 
+		 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
+		 * Return: write counters to the user passed counter struct
+		 * NB: both 1->0 and 0->1 transitions are counted except for
+		 *     RI where only 0->1 is counted.
+		 */
+		case TIOCGICOUNT:
+			spin_lock_irqsave(&info->lock, flags);
+			cnow = info->icount;
+			spin_unlock_irqrestore(&info->lock, flags);
+			p_cuser = argp;
+			if (put_user(cnow.cts, &p_cuser->cts) ||
+			    put_user(cnow.dsr, &p_cuser->dsr) ||
+			    put_user(cnow.rng, &p_cuser->rng) ||
+			    put_user(cnow.dcd, &p_cuser->dcd))
+				return -EFAULT;
+
+			return 0;
+	case TIOCGHAYESESP:
+		return get_esp_config(info, argp);
+	case TIOCSHAYESESP:
+		return set_esp_config(info, argp);
+
+		default:
+			return -ENOIOCTLCMD;
+		}
+	return 0;
+}
+
+static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+
+	if (   (tty->termios->c_cflag == old_termios->c_cflag)
+	    && (   RELEVANT_IFLAG(tty->termios->c_iflag) 
+		== RELEVANT_IFLAG(old_termios->c_iflag)))
+		return;
+
+	change_speed(info);
+
+	spin_lock_irqsave(&info->lock, flags);
+
+	/* Handle transition to B0 status */
+	if ((old_termios->c_cflag & CBAUD) &&
+		!(tty->termios->c_cflag & CBAUD)) {
+		info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
+		serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
+		serial_out(info, UART_ESI_CMD2, UART_MCR);
+		serial_out(info, UART_ESI_CMD2, info->MCR);
+	}
+
+	/* Handle transition away from B0 status */
+	if (!(old_termios->c_cflag & CBAUD) &&
+		(tty->termios->c_cflag & CBAUD)) {
+		info->MCR |= (UART_MCR_DTR | UART_MCR_RTS);
+		serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
+		serial_out(info, UART_ESI_CMD2, UART_MCR);
+		serial_out(info, UART_ESI_CMD2, info->MCR);
+	}
+
+	spin_unlock_irqrestore(&info->lock, flags);
+
+	/* Handle turning of CRTSCTS */
+	if ((old_termios->c_cflag & CRTSCTS) &&
+	    !(tty->termios->c_cflag & CRTSCTS)) {
+		rs_start(tty);
+	}
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_close()
+ * 
+ * This routine is called when the serial port gets closed.  First, we
+ * wait for the last remaining data to be sent.  Then, we unlink its
+ * async structure from the interrupt chain if necessary, and we free
+ * that IRQ if nothing is left in the chain.
+ * ------------------------------------------------------------
+ */
+static void rs_close(struct tty_struct *tty, struct file * filp)
+{
+	struct esp_struct * info = (struct esp_struct *)tty->driver_data;
+	unsigned long flags;
+
+	if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
+		return;
+	
+	spin_lock_irqsave(&info->lock, flags);
+	
+	if (tty_hung_up_p(filp)) {
+		DBG_CNT("before DEC-hung");
+		goto out;
+	}
+	
+#ifdef SERIAL_DEBUG_OPEN
+	printk("rs_close ttys%d, count = %d\n", info->line, info->count);
+#endif
+	if ((tty->count == 1) && (info->count != 1)) {
+		/*
+		 * Uh, oh.  tty->count is 1, which means that the tty
+		 * structure will be freed.  Info->count should always
+		 * be one in these conditions.  If it's greater than
+		 * one, we've got real problems, since it means the
+		 * serial port won't be shutdown.
+		 */
+		printk("rs_close: bad serial port count; tty->count is 1, "
+		       "info->count is %d\n", info->count);
+		info->count = 1;
+	}
+	if (--info->count < 0) {
+		printk("rs_close: bad serial port count for ttys%d: %d\n",
+		       info->line, info->count);
+		info->count = 0;
+	}
+	if (info->count) {
+		DBG_CNT("before DEC-2");
+		goto out;
+	}
+	info->flags |= ASYNC_CLOSING;
+
+	spin_unlock_irqrestore(&info->lock, flags);
+	/*
+	 * Now we wait for the transmit buffer to clear; and we notify 
+	 * the line discipline to only process XON/XOFF characters.
+	 */
+	tty->closing = 1;
+	if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
+		tty_wait_until_sent(tty, info->closing_wait);
+	/*
+	 * At this point we stop accepting input.  To do this, we
+	 * disable the receive line status interrupts, and tell the
+	 * interrupt driver to stop checking the data ready bit in the
+	 * line status register.
+	 */
+	/* info->IER &= ~UART_IER_RLSI; */
+	info->IER &= ~UART_IER_RDI;
+	info->read_status_mask &= ~UART_LSR_DR;
+	if (info->flags & ASYNC_INITIALIZED) {
+
+		spin_lock_irqsave(&info->lock, flags);
+		serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
+		serial_out(info, UART_ESI_CMD2, info->IER);
+
+		/* disable receive timeout */
+		serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
+		serial_out(info, UART_ESI_CMD2, 0x00);
+
+		spin_unlock_irqrestore(&info->lock, flags);
+
+		/*
+		 * Before we drop DTR, make sure the UART transmitter
+		 * has completely drained; this is especially
+		 * important if there is a transmit FIFO!
+		 */
+		rs_wait_until_sent(tty, info->timeout);
+	}
+	shutdown(info);
+	if (tty->driver->flush_buffer)
+		tty->driver->flush_buffer(tty);
+	tty_ldisc_flush(tty);
+	tty->closing = 0;
+	info->event = 0;
+	info->tty = NULL;
+
+	if (info->blocked_open) {
+		if (info->close_delay) {
+			msleep_interruptible(jiffies_to_msecs(info->close_delay));
+		}
+		wake_up_interruptible(&info->open_wait);
+	}
+	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
+	wake_up_interruptible(&info->close_wait);
+	return;
+
+out:
+	spin_unlock_irqrestore(&info->lock, flags);
+}
+
+static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+	struct esp_struct *info = (struct esp_struct *)tty->driver_data;
+	unsigned long orig_jiffies, char_time;
+	unsigned long flags;
+
+	if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
+		return;
+
+	orig_jiffies = jiffies;
+	char_time = ((info->timeout - HZ / 50) / 1024) / 5;
+
+	if (!char_time)
+		char_time = 1;
+
+	spin_lock_irqsave(&info->lock, flags);
+	serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
+	serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
+
+	while ((serial_in(info, UART_ESI_STAT1) != 0x03) ||
+		(serial_in(info, UART_ESI_STAT2) != 0xff)) {
+
+		spin_unlock_irqrestore(&info->lock, flags);
+		msleep_interruptible(jiffies_to_msecs(char_time));
+
+		if (signal_pending(current))
+			break;
+
+		if (timeout && time_after(jiffies, orig_jiffies + timeout))
+			break;
+
+		spin_lock_irqsave(&info->lock, flags);
+		serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
+		serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
+	}
+	spin_unlock_irqrestore(&info->lock, flags);
+	set_current_state(TASK_RUNNING);
+}
+
+/*
+ * esp_hangup() --- called by tty_hangup() when a hangup is signaled.
+ */
+static void esp_hangup(struct tty_struct *tty)
+{
+	struct esp_struct * info = (struct esp_struct *)tty->driver_data;
+	
+	if (serial_paranoia_check(info, tty->name, "esp_hangup"))
+		return;
+	
+	rs_flush_buffer(tty);
+	shutdown(info);
+	info->event = 0;
+	info->count = 0;
+	info->flags &= ~ASYNC_NORMAL_ACTIVE;
+	info->tty = NULL;
+	wake_up_interruptible(&info->open_wait);
+}
+
+/*
+ * ------------------------------------------------------------
+ * esp_open() and friends
+ * ------------------------------------------------------------
+ */
+static int block_til_ready(struct tty_struct *tty, struct file * filp,
+			   struct esp_struct *info)
+{
+	DECLARE_WAITQUEUE(wait, current);
+	int		retval;
+	int		do_clocal = 0;
+	unsigned long	flags;
+
+	/*
+	 * If the device is in the middle of being closed, then block
+	 * until it's done, and then try again.
+	 */
+	if (tty_hung_up_p(filp) ||
+	    (info->flags & ASYNC_CLOSING)) {
+		if (info->flags & ASYNC_CLOSING)
+			interruptible_sleep_on(&info->close_wait);
+#ifdef SERIAL_DO_RESTART
+		if (info->flags & ASYNC_HUP_NOTIFY)
+			return -EAGAIN;
+		else
+			return -ERESTARTSYS;
+#else
+		return -EAGAIN;
+#endif
+	}
+
+	/*
+	 * If non-blocking mode is set, or the port is not enabled,
+	 * then make the check up front and then exit.
+	 */
+	if ((filp->f_flags & O_NONBLOCK) ||
+	    (tty->flags & (1 << TTY_IO_ERROR))) {
+		info->flags |= ASYNC_NORMAL_ACTIVE;
+		return 0;
+	}
+
+	if (tty->termios->c_cflag & CLOCAL)
+		do_clocal = 1;
+
+	/*
+	 * Block waiting for the carrier detect and the line to become
+	 * free (i.e., not in use by the callout).  While we are in
+	 * this loop, info->count is dropped by one, so that
+	 * rs_close() knows when to free things.  We restore it upon
+	 * exit, either normal or abnormal.
+	 */
+	retval = 0;
+	add_wait_queue(&info->open_wait, &wait);
+#ifdef SERIAL_DEBUG_OPEN
+	printk("block_til_ready before block: ttys%d, count = %d\n",
+	       info->line, info->count);
+#endif
+	spin_lock_irqsave(&info->lock, flags);
+	if (!tty_hung_up_p(filp)) 
+		info->count--;
+	info->blocked_open++;
+	while (1) {
+		if ((tty->termios->c_cflag & CBAUD)) {
+			unsigned int scratch;
+
+			serial_out(info, UART_ESI_CMD1, ESI_READ_UART);
+			serial_out(info, UART_ESI_CMD2, UART_MCR);
+			scratch = serial_in(info, UART_ESI_STAT1);
+			serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
+			serial_out(info, UART_ESI_CMD2, UART_MCR);
+			serial_out(info, UART_ESI_CMD2,
+				scratch | UART_MCR_DTR | UART_MCR_RTS);
+		}
+		set_current_state(TASK_INTERRUPTIBLE);
+		if (tty_hung_up_p(filp) ||
+		    !(info->flags & ASYNC_INITIALIZED)) {
+#ifdef SERIAL_DO_RESTART
+			if (info->flags & ASYNC_HUP_NOTIFY)
+				retval = -EAGAIN;
+			else
+				retval = -ERESTARTSYS;	
+#else
+			retval = -EAGAIN;
+#endif
+			break;
+		}
+
+		serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
+		if (serial_in(info, UART_ESI_STAT2) & UART_MSR_DCD)
+			do_clocal = 1;
+
+		if (!(info->flags & ASYNC_CLOSING) &&
+		    (do_clocal))
+			break;
+		if (signal_pending(current)) {
+			retval = -ERESTARTSYS;
+			break;
+		}
+#ifdef SERIAL_DEBUG_OPEN
+		printk("block_til_ready blocking: ttys%d, count = %d\n",
+		       info->line, info->count);
+#endif
+		spin_unlock_irqrestore(&info->lock, flags);
+		schedule();
+		spin_lock_irqsave(&info->lock, flags);
+	}
+	set_current_state(TASK_RUNNING);
+	remove_wait_queue(&info->open_wait, &wait);
+	if (!tty_hung_up_p(filp))
+		info->count++;
+	info->blocked_open--;
+	spin_unlock_irqrestore(&info->lock, flags);
+#ifdef SERIAL_DEBUG_OPEN
+	printk("block_til_ready after blocking: ttys%d, count = %d\n",
+	       info->line, info->count);
+#endif
+	if (retval)
+		return retval;
+	info->flags |= ASYNC_NORMAL_ACTIVE;
+	return 0;
+}	
+
+/*
+ * This routine is called whenever a serial port is opened.  It
+ * enables interrupts for a serial port, linking in its async structure into
+ * the IRQ chain.   It also performs the serial-specific
+ * initialization for the tty structure.
+ */
+static int esp_open(struct tty_struct *tty, struct file * filp)
+{
+	struct esp_struct	*info;
+	int 			retval, line;
+	unsigned long		flags;
+
+	line = tty->index;
+	if ((line < 0) || (line >= NR_PORTS))
+		return -ENODEV;
+
+	/* find the port in the chain */
+
+	info = ports;
+
+	while (info && (info->line != line))
+		info = info->next_port;
+
+	if (!info) {
+		serial_paranoia_check(info, tty->name, "esp_open");
+		return -ENODEV;
+	}
+
+#ifdef SERIAL_DEBUG_OPEN
+	printk("esp_open %s, count = %d\n", tty->name, info->count);
+#endif
+	spin_lock_irqsave(&info->lock, flags);
+	info->count++;
+	tty->driver_data = info;
+	info->tty = tty;
+
+	if (!tmp_buf) {
+		tmp_buf = (unsigned char *) get_zeroed_page(GFP_KERNEL);
+		if (!tmp_buf)
+			return -ENOMEM;
+	}
+	
+	/*
+	 * Start up serial port
+	 */
+	retval = startup(info);
+	if (retval)
+		return retval;
+
+	retval = block_til_ready(tty, filp, info);
+	if (retval) {
+#ifdef SERIAL_DEBUG_OPEN
+		printk("esp_open returning after block_til_ready with %d\n",
+		       retval);
+#endif
+		return retval;
+	}
+
+#ifdef SERIAL_DEBUG_OPEN
+	printk("esp_open %s successful...", tty->name);
+#endif
+	return 0;
+}
+
+/*
+ * ---------------------------------------------------------------------
+ * espserial_init() and friends
+ *
+ * espserial_init() is called at boot-time to initialize the serial driver.
+ * ---------------------------------------------------------------------
+ */
+
+/*
+ * This routine prints out the appropriate serial driver version
+ * number, and identifies which options were configured into this
+ * driver.
+ */
+ 
+static inline void show_serial_version(void)
+{
+ 	printk(KERN_INFO "%s version %s (DMA %u)\n",
+		serial_name, serial_version, dma);
+}
+
+/*
+ * This routine is called by espserial_init() to initialize a specific serial
+ * port.
+ */
+static inline int autoconfig(struct esp_struct * info)
+{
+	int port_detected = 0;
+	unsigned long flags;
+
+	if (!request_region(info->port, REGION_SIZE, "esp serial"))
+		return -EIO;
+
+	spin_lock_irqsave(&info->lock, flags);
+	/*
+	 * Check for ESP card
+	 */
+
+	if (serial_in(info, UART_ESI_BASE) == 0xf3) {
+		serial_out(info, UART_ESI_CMD1, 0x00);
+		serial_out(info, UART_ESI_CMD1, 0x01);
+
+		if ((serial_in(info, UART_ESI_STAT2) & 0x70) == 0x20) {
+			port_detected = 1;
+
+			if (!(info->irq)) {
+				serial_out(info, UART_ESI_CMD1, 0x02);
+
+				if (serial_in(info, UART_ESI_STAT1) & 0x01)
+					info->irq = 3;
+				else
+					info->irq = 4;
+			}
+
+
+			/* put card in enhanced mode */
+			/* this prevents access through */
+			/* the "old" IO ports */
+			esp_basic_init(info);
+
+			/* clear out MCR */
+			serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
+			serial_out(info, UART_ESI_CMD2, UART_MCR);
+			serial_out(info, UART_ESI_CMD2, 0x00);
+		}
+	}
+	if (!port_detected)
+		release_region(info->port, REGION_SIZE);
+
+	spin_unlock_irqrestore(&info->lock, flags);
+	return (port_detected);
+}
+
+static struct tty_operations esp_ops = {
+	.open = esp_open,
+	.close = rs_close,
+	.write = rs_write,
+	.put_char = rs_put_char,
+	.flush_chars = rs_flush_chars,
+	.write_room = rs_write_room,
+	.chars_in_buffer = rs_chars_in_buffer,
+	.flush_buffer = rs_flush_buffer,
+	.ioctl = rs_ioctl,
+	.throttle = rs_throttle,
+	.unthrottle = rs_unthrottle,
+	.set_termios = rs_set_termios,
+	.stop = rs_stop,
+	.start = rs_start,
+	.hangup = esp_hangup,
+	.break_ctl = esp_break,
+	.wait_until_sent = rs_wait_until_sent,
+	.tiocmget = esp_tiocmget,
+	.tiocmset = esp_tiocmset,
+};
+
+/*
+ * The serial driver boot-time initialization code!
+ */
+static int __init espserial_init(void)
+{
+	int i, offset;
+	struct esp_struct * info;
+	struct esp_struct *last_primary = NULL;
+	int esp[] = {0x100,0x140,0x180,0x200,0x240,0x280,0x300,0x380};
+
+	esp_driver = alloc_tty_driver(NR_PORTS);
+	if (!esp_driver)
+		return -ENOMEM;
+	
+	for (i = 0; i < NR_PRIMARY; i++) {
+		if (irq[i] != 0) {
+			if ((irq[i] < 2) || (irq[i] > 15) || (irq[i] == 6) ||
+			    (irq[i] == 8) || (irq[i] == 13))
+				irq[i] = 0;
+			else if (irq[i] == 2)
+				irq[i] = 9;
+		}
+	}
+
+	if ((dma != 1) && (dma != 3))
+		dma = 0;
+
+	if ((rx_trigger < 1) || (rx_trigger > 1023))
+		rx_trigger = 768;
+
+	if ((tx_trigger < 1) || (tx_trigger > 1023))
+		tx_trigger = 768;
+
+	if ((flow_off < 1) || (flow_off > 1023))
+		flow_off = 1016;
+	
+	if ((flow_on < 1) || (flow_on > 1023))
+		flow_on = 944;
+
+	if ((rx_timeout < 0) || (rx_timeout > 255))
+		rx_timeout = 128;
+	
+	if (flow_on >= flow_off)
+		flow_on = flow_off - 1;
+
+	show_serial_version();
+
+	/* Initialize the tty_driver structure */
+	
+	esp_driver->owner = THIS_MODULE;
+	esp_driver->name = "ttyP";
+	esp_driver->devfs_name = "tts/P";
+	esp_driver->major = ESP_IN_MAJOR;
+	esp_driver->minor_start = 0;
+	esp_driver->type = TTY_DRIVER_TYPE_SERIAL;
+	esp_driver->subtype = SERIAL_TYPE_NORMAL;
+	esp_driver->init_termios = tty_std_termios;
+	esp_driver->init_termios.c_cflag =
+		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+	esp_driver->flags = TTY_DRIVER_REAL_RAW;
+	tty_set_operations(esp_driver, &esp_ops);
+	if (tty_register_driver(esp_driver))
+	{
+		printk(KERN_ERR "Couldn't register esp serial driver");
+		put_tty_driver(esp_driver);
+		return 1;
+	}
+
+	info = kmalloc(sizeof(struct esp_struct), GFP_KERNEL);
+
+	if (!info)
+	{
+		printk(KERN_ERR "Couldn't allocate memory for esp serial device information\n");
+		tty_unregister_driver(esp_driver);
+		put_tty_driver(esp_driver);
+		return 1;
+	}
+
+	memset((void *)info, 0, sizeof(struct esp_struct));
+	/* rx_trigger, tx_trigger are needed by autoconfig */
+	info->config.rx_trigger = rx_trigger;
+	info->config.tx_trigger = tx_trigger;
+
+	i = 0;
+	offset = 0;
+
+	do {
+		info->port = esp[i] + offset;
+		info->irq = irq[i];
+		info->line = (i * 8) + (offset / 8);
+
+		if (!autoconfig(info)) {
+			i++;
+			offset = 0;
+			continue;
+		}
+
+		info->custom_divisor = (divisor[i] >> (offset / 2)) & 0xf;
+		info->flags = STD_COM_FLAGS;
+		if (info->custom_divisor)
+			info->flags |= ASYNC_SPD_CUST;
+		info->magic = ESP_MAGIC;
+		info->close_delay = 5*HZ/10;
+		info->closing_wait = 30*HZ;
+		INIT_WORK(&info->tqueue, do_softint, info);
+		INIT_WORK(&info->tqueue_hangup, do_serial_hangup, info);
+		info->config.rx_timeout = rx_timeout;
+		info->config.flow_on = flow_on;
+		info->config.flow_off = flow_off;
+		info->config.pio_threshold = pio_threshold;
+		info->next_port = ports;
+		init_waitqueue_head(&info->open_wait);
+		init_waitqueue_head(&info->close_wait);
+		init_waitqueue_head(&info->delta_msr_wait);
+		init_waitqueue_head(&info->break_wait);
+		spin_lock_init(&info->lock);
+		ports = info;
+		printk(KERN_INFO "ttyP%d at 0x%04x (irq = %d) is an ESP ",
+			info->line, info->port, info->irq);
+
+		if (info->line % 8) {
+			printk("secondary port\n");
+			/* 8 port cards can't do DMA */
+			info->stat_flags |= ESP_STAT_NEVER_DMA;
+
+			if (last_primary)
+				last_primary->stat_flags |= ESP_STAT_NEVER_DMA;
+		} else {
+			printk("primary port\n");
+			last_primary = info;
+			irq[i] = info->irq;
+		}
+
+		if (!dma)
+			info->stat_flags |= ESP_STAT_NEVER_DMA;
+
+		info = kmalloc(sizeof(struct esp_struct), GFP_KERNEL);
+		if (!info)
+		{
+			printk(KERN_ERR "Couldn't allocate memory for esp serial device information\n"); 
+
+			/* allow use of the already detected ports */
+			return 0;
+		}
+
+		memset((void *)info, 0, sizeof(struct esp_struct));
+		/* rx_trigger, tx_trigger are needed by autoconfig */
+		info->config.rx_trigger = rx_trigger;
+		info->config.tx_trigger = tx_trigger;
+
+		if (offset == 56) {
+			i++;
+			offset = 0;
+		} else {
+			offset += 8;
+		}
+	} while (i < NR_PRIMARY);
+
+	/* free the last port memory allocation */
+	kfree(info);
+
+	return 0;
+}
+
+static void __exit espserial_exit(void) 
+{
+	int e1;
+	struct esp_struct *temp_async;
+	struct esp_pio_buffer *pio_buf;
+
+	/* printk("Unloading %s: version %s\n", serial_name, serial_version); */
+	if ((e1 = tty_unregister_driver(esp_driver)))
+		printk("SERIAL: failed to unregister serial driver (%d)\n",
+		       e1);
+	put_tty_driver(esp_driver);
+
+	while (ports) {
+		if (ports->port) {
+			release_region(ports->port, REGION_SIZE);
+		}
+		temp_async = ports->next_port;
+		kfree(ports);
+		ports = temp_async;
+	}
+
+	if (dma_buffer)
+		free_pages((unsigned long)dma_buffer,
+			get_order(DMA_BUFFER_SZ));
+
+	if (tmp_buf)
+		free_page((unsigned long)tmp_buf);
+
+	while (free_pio_buf) {
+		pio_buf = free_pio_buf->next;
+		kfree(free_pio_buf);
+		free_pio_buf = pio_buf;
+	}
+}
+
+module_init(espserial_init);
+module_exit(espserial_exit);