Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
[linux-2.6] / drivers / char / esp.c
1 /*
2  *  esp.c - driver for Hayes ESP serial cards
3  *
4  *  --- Notices from serial.c, upon which this driver is based ---
5  *
6  *  Copyright (C) 1991, 1992  Linus Torvalds
7  *
8  *  Extensively rewritten by Theodore Ts'o, 8/16/92 -- 9/14/92.  Now
9  *  much more extensible to support other serial cards based on the
10  *  16450/16550A UART's.  Added support for the AST FourPort and the
11  *  Accent Async board.  
12  *
13  *  set_serial_info fixed to set the flags, custom divisor, and uart
14  *      type fields.  Fix suggested by Michael K. Johnson 12/12/92.
15  *
16  *  11/95: TIOCMIWAIT, TIOCGICOUNT by Angelo Haritsis <ah@doc.ic.ac.uk>
17  *
18  *  03/96: Modularised by Angelo Haritsis <ah@doc.ic.ac.uk>
19  *
20  *  rs_set_termios fixed to look also for changes of the input
21  *      flags INPCK, BRKINT, PARMRK, IGNPAR and IGNBRK.
22  *                                            Bernd Anh�pl 05/17/96.
23  *
24  * --- End of notices from serial.c ---
25  *
26  * Support for the ESP serial card by Andrew J. Robinson
27  *     <arobinso@nyx.net> (Card detection routine taken from a patch
28  *     by Dennis J. Boylan).  Patches to allow use with 2.1.x contributed
29  *     by Chris Faylor.
30  *
31  * Most recent changes: (Andrew J. Robinson)
32  *   Support for PIO mode.  This allows the driver to work properly with
33  *     multiport cards.
34  *
35  * Arnaldo Carvalho de Melo <acme@conectiva.com.br> -
36  * several cleanups, use module_init/module_exit, etc
37  *
38  * This module exports the following rs232 io functions:
39  *
40  *      int espserial_init(void);
41  */
42
43 #include <linux/module.h>
44 #include <linux/errno.h>
45 #include <linux/signal.h>
46 #include <linux/sched.h>
47 #include <linux/interrupt.h>
48 #include <linux/tty.h>
49 #include <linux/tty_flip.h>
50 #include <linux/serial.h>
51 #include <linux/serialP.h>
52 #include <linux/serial_reg.h>
53 #include <linux/major.h>
54 #include <linux/string.h>
55 #include <linux/fcntl.h>
56 #include <linux/ptrace.h>
57 #include <linux/ioport.h>
58 #include <linux/mm.h>
59 #include <linux/init.h>
60 #include <linux/delay.h>
61
62 #include <asm/system.h>
63 #include <asm/io.h>
64 #include <asm/bitops.h>
65
66 #include <asm/dma.h>
67 #include <linux/slab.h>
68 #include <asm/uaccess.h>
69
70 #include <linux/hayesesp.h>
71
72 #define NR_PORTS 64     /* maximum number of ports */
73 #define NR_PRIMARY 8    /* maximum number of primary ports */
74 #define REGION_SIZE 8   /* size of io region to request */
75
76 /* The following variables can be set by giving module options */
77 static int irq[NR_PRIMARY];     /* IRQ for each base port */
78 static unsigned int divisor[NR_PRIMARY]; /* custom divisor for each port */
79 static unsigned int dma = ESP_DMA_CHANNEL; /* DMA channel */
80 static unsigned int rx_trigger = ESP_RX_TRIGGER;
81 static unsigned int tx_trigger = ESP_TX_TRIGGER;
82 static unsigned int flow_off = ESP_FLOW_OFF;
83 static unsigned int flow_on = ESP_FLOW_ON;
84 static unsigned int rx_timeout = ESP_RX_TMOUT;
85 static unsigned int pio_threshold = ESP_PIO_THRESHOLD;
86
87 MODULE_LICENSE("GPL");
88
89 module_param_array(irq, int, NULL, 0);
90 module_param_array(divisor, uint, NULL, 0);
91 module_param(dma, uint, 0);
92 module_param(rx_trigger, uint, 0);
93 module_param(tx_trigger, uint, 0);
94 module_param(flow_off, uint, 0);
95 module_param(flow_on, uint, 0);
96 module_param(rx_timeout, uint, 0);
97 module_param(pio_threshold, uint, 0);
98
99 /* END */
100
101 static char *dma_buffer;
102 static int dma_bytes;
103 static struct esp_pio_buffer *free_pio_buf;
104
105 #define DMA_BUFFER_SZ 1024
106
107 #define WAKEUP_CHARS 1024
108
109 static char serial_name[] __initdata = "ESP serial driver";
110 static char serial_version[] __initdata = "2.2";
111
112 static struct tty_driver *esp_driver;
113
114 /* serial subtype definitions */
115 #define SERIAL_TYPE_NORMAL      1
116
117 /*
118  * Serial driver configuration section.  Here are the various options:
119  *
120  * SERIAL_PARANOIA_CHECK
121  *              Check the magic number for the esp_structure where
122  *              ever possible.
123  */
124
125 #undef SERIAL_PARANOIA_CHECK
126 #define SERIAL_DO_RESTART
127
128 #undef SERIAL_DEBUG_INTR
129 #undef SERIAL_DEBUG_OPEN
130 #undef SERIAL_DEBUG_FLOW
131
132 #if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
133 #define DBG_CNT(s) printk("(%s): [%x] refc=%d, serc=%d, ttyc=%d -> %s\n", \
134  tty->name, (info->flags), serial_driver.refcount,info->count,tty->count,s)
135 #else
136 #define DBG_CNT(s)
137 #endif
138
139 static struct esp_struct *ports;
140
141 static void change_speed(struct esp_struct *info);
142 static void rs_wait_until_sent(struct tty_struct *, int);
143
144 /*
145  * The ESP card has a clock rate of 14.7456 MHz (that is, 2**ESPC_SCALE
146  * times the normal 1.8432 Mhz clock of most serial boards).
147  */
148 #define BASE_BAUD ((1843200 / 16) * (1 << ESPC_SCALE))
149
150 /* Standard COM flags (except for COM4, because of the 8514 problem) */
151 #define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
152
153 static inline int serial_paranoia_check(struct esp_struct *info,
154                                         char *name, const char *routine)
155 {
156 #ifdef SERIAL_PARANOIA_CHECK
157         static const char badmagic[] = KERN_WARNING
158                 "Warning: bad magic number for serial struct (%s) in %s\n";
159         static const char badinfo[] = KERN_WARNING
160                 "Warning: null esp_struct for (%s) in %s\n";
161
162         if (!info) {
163                 printk(badinfo, name, routine);
164                 return 1;
165         }
166         if (info->magic != ESP_MAGIC) {
167                 printk(badmagic, name, routine);
168                 return 1;
169         }
170 #endif
171         return 0;
172 }
173
174 static inline unsigned int serial_in(struct esp_struct *info, int offset)
175 {
176         return inb(info->port + offset);
177 }
178
179 static inline void serial_out(struct esp_struct *info, int offset,
180                               unsigned char value)
181 {
182         outb(value, info->port+offset);
183 }
184
185 /*
186  * ------------------------------------------------------------
187  * rs_stop() and rs_start()
188  *
189  * This routines are called before setting or resetting tty->stopped.
190  * They enable or disable transmitter interrupts, as necessary.
191  * ------------------------------------------------------------
192  */
193 static void rs_stop(struct tty_struct *tty)
194 {
195         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
196         unsigned long flags;
197
198         if (serial_paranoia_check(info, tty->name, "rs_stop"))
199                 return;
200
201         spin_lock_irqsave(&info->lock, flags);
202         if (info->IER & UART_IER_THRI) {
203                 info->IER &= ~UART_IER_THRI;
204                 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
205                 serial_out(info, UART_ESI_CMD2, info->IER);
206         }
207         spin_unlock_irqrestore(&info->lock, flags);
208 }
209
210 static void rs_start(struct tty_struct *tty)
211 {
212         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
213         unsigned long flags;
214         
215         if (serial_paranoia_check(info, tty->name, "rs_start"))
216                 return;
217         
218         spin_lock_irqsave(&info->lock, flags);
219         if (info->xmit_cnt && info->xmit_buf && !(info->IER & UART_IER_THRI)) {
220                 info->IER |= UART_IER_THRI;
221                 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
222                 serial_out(info, UART_ESI_CMD2, info->IER);
223         }
224         spin_unlock_irqrestore(&info->lock, flags);
225 }
226
227 /*
228  * ----------------------------------------------------------------------
229  *
230  * Here starts the interrupt handling routines.  All of the following
231  * subroutines are declared as inline and are folded into
232  * rs_interrupt().  They were separated out for readability's sake.
233  *
234  * Note: rs_interrupt() is a "fast" interrupt, which means that it
235  * runs with interrupts turned off.  People who may want to modify
236  * rs_interrupt() should try to keep the interrupt handler as fast as
237  * possible.  After you are done making modifications, it is not a bad
238  * idea to do:
239  * 
240  * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
241  *
242  * and look at the resulting assemble code in serial.s.
243  *
244  *                              - Ted Ts'o (tytso@mit.edu), 7-Mar-93
245  * -----------------------------------------------------------------------
246  */
247
248 /*
249  * This routine is used by the interrupt handler to schedule
250  * processing in the software interrupt portion of the driver.
251  */
252 static inline void rs_sched_event(struct esp_struct *info,
253                                   int event)
254 {
255         info->event |= 1 << event;
256         schedule_work(&info->tqueue);
257 }
258
259 static DEFINE_SPINLOCK(pio_lock);
260
261 static inline struct esp_pio_buffer *get_pio_buffer(void)
262 {
263         struct esp_pio_buffer *buf;
264         unsigned long flags;
265
266         spin_lock_irqsave(&pio_lock, flags);
267         if (free_pio_buf) {
268                 buf = free_pio_buf;
269                 free_pio_buf = buf->next;
270         } else {
271                 buf = kmalloc(sizeof(struct esp_pio_buffer), GFP_ATOMIC);
272         }
273         spin_unlock_irqrestore(&pio_lock, flags);
274         return buf;
275 }
276
277 static inline void release_pio_buffer(struct esp_pio_buffer *buf)
278 {
279         unsigned long flags;
280         spin_lock_irqsave(&pio_lock, flags);
281         buf->next = free_pio_buf;
282         free_pio_buf = buf;
283         spin_unlock_irqrestore(&pio_lock, flags);
284 }
285
286 static inline void receive_chars_pio(struct esp_struct *info, int num_bytes)
287 {
288         struct tty_struct *tty = info->tty;
289         int i;
290         struct esp_pio_buffer *pio_buf;
291         struct esp_pio_buffer *err_buf;
292         unsigned char status_mask;
293
294         pio_buf = get_pio_buffer();
295
296         if (!pio_buf)
297                 return;
298
299         err_buf = get_pio_buffer();
300
301         if (!err_buf) {
302                 release_pio_buffer(pio_buf);
303                 return;
304         }
305
306         status_mask = (info->read_status_mask >> 2) & 0x07;
307                 
308         for (i = 0; i < num_bytes - 1; i += 2) {
309                 *((unsigned short *)(pio_buf->data + i)) =
310                         inw(info->port + UART_ESI_RX);
311                 err_buf->data[i] = serial_in(info, UART_ESI_RWS);
312                 err_buf->data[i + 1] = (err_buf->data[i] >> 3) & status_mask;
313                 err_buf->data[i] &= status_mask;
314         }
315
316         if (num_bytes & 0x0001) {
317                 pio_buf->data[num_bytes - 1] = serial_in(info, UART_ESI_RX);
318                 err_buf->data[num_bytes - 1] =
319                         (serial_in(info, UART_ESI_RWS) >> 3) & status_mask;
320         }
321
322         /* make sure everything is still ok since interrupts were enabled */
323         tty = info->tty;
324
325         if (!tty) {
326                 release_pio_buffer(pio_buf);
327                 release_pio_buffer(err_buf);
328                 info->stat_flags &= ~ESP_STAT_RX_TIMEOUT;
329                 return;
330         }
331
332         status_mask = (info->ignore_status_mask >> 2) & 0x07;
333
334         for (i = 0; i < num_bytes; i++) {
335                 if (!(err_buf->data[i] & status_mask)) {
336                         int flag = 0;
337
338                         if (err_buf->data[i] & 0x04) {
339                                 flag = TTY_BREAK;
340                                 if (info->flags & ASYNC_SAK)
341                                         do_SAK(tty);
342                         }
343                         else if (err_buf->data[i] & 0x02)
344                                 flag = TTY_FRAME;
345                         else if (err_buf->data[i] & 0x01)
346                                 flag = TTY_PARITY;
347                         tty_insert_flip_char(tty, pio_buf->data[i], flag);
348                 }
349         }
350
351         tty_schedule_flip(tty);
352
353         info->stat_flags &= ~ESP_STAT_RX_TIMEOUT;
354         release_pio_buffer(pio_buf);
355         release_pio_buffer(err_buf);
356 }
357
358 static inline void receive_chars_dma(struct esp_struct *info, int num_bytes)
359 {
360         unsigned long flags;
361         info->stat_flags &= ~ESP_STAT_RX_TIMEOUT;
362         dma_bytes = num_bytes;
363         info->stat_flags |= ESP_STAT_DMA_RX;
364         
365         flags=claim_dma_lock();
366         disable_dma(dma);
367         clear_dma_ff(dma);
368         set_dma_mode(dma, DMA_MODE_READ);
369         set_dma_addr(dma, isa_virt_to_bus(dma_buffer));
370         set_dma_count(dma, dma_bytes);
371         enable_dma(dma);
372         release_dma_lock(flags);
373         
374         serial_out(info, UART_ESI_CMD1, ESI_START_DMA_RX);
375 }
376
377 static inline void receive_chars_dma_done(struct esp_struct *info,
378                                             int status)
379 {
380         struct tty_struct *tty = info->tty;
381         int num_bytes;
382         unsigned long flags;
383         
384         flags=claim_dma_lock();
385         disable_dma(dma);
386         clear_dma_ff(dma);
387
388         info->stat_flags &= ~ESP_STAT_DMA_RX;
389         num_bytes = dma_bytes - get_dma_residue(dma);
390         release_dma_lock(flags);
391         
392         info->icount.rx += num_bytes;
393
394         if (num_bytes > 0) {
395                 tty_insert_flip_string(tty, dma_buffer, num_bytes - 1);
396
397                 status &= (0x1c & info->read_status_mask);
398                 
399                 /* Is the status significant or do we throw the last byte ? */
400                 if (!(status & info->ignore_status_mask)) {
401                         int statflag = 0;
402
403                         if (status & 0x10) {
404                                 statflag = TTY_BREAK;
405                                 (info->icount.brk)++;
406                                 if (info->flags & ASYNC_SAK)
407                                         do_SAK(tty);
408                         } else if (status & 0x08) {
409                                 statflag = TTY_FRAME;
410                                 (info->icount.frame)++;
411                         }
412                         else if (status & 0x04) {
413                                 statflag = TTY_PARITY;
414                                 (info->icount.parity)++;
415                         }
416                         tty_insert_flip_char(tty, dma_buffer[num_bytes - 1], statflag);
417                 }
418                 tty_schedule_flip(tty);
419         }
420
421         if (dma_bytes != num_bytes) {
422                 num_bytes = dma_bytes - num_bytes;
423                 dma_bytes = 0;
424                 receive_chars_dma(info, num_bytes);
425         } else
426                 dma_bytes = 0;
427 }
428
429 /* Caller must hold info->lock */
430
431 static inline void transmit_chars_pio(struct esp_struct *info,
432                                         int space_avail)
433 {
434         int i;
435         struct esp_pio_buffer *pio_buf;
436
437         pio_buf = get_pio_buffer();
438
439         if (!pio_buf)
440                 return;
441
442         while (space_avail && info->xmit_cnt) {
443                 if (info->xmit_tail + space_avail <= ESP_XMIT_SIZE) {
444                         memcpy(pio_buf->data,
445                                &(info->xmit_buf[info->xmit_tail]),
446                                space_avail);
447                 } else {
448                         i = ESP_XMIT_SIZE - info->xmit_tail;
449                         memcpy(pio_buf->data,
450                                &(info->xmit_buf[info->xmit_tail]), i);
451                         memcpy(&(pio_buf->data[i]), info->xmit_buf,
452                                space_avail - i);
453                 }
454
455                 info->xmit_cnt -= space_avail;
456                 info->xmit_tail = (info->xmit_tail + space_avail) &
457                         (ESP_XMIT_SIZE - 1);
458
459                 for (i = 0; i < space_avail - 1; i += 2) {
460                         outw(*((unsigned short *)(pio_buf->data + i)),
461                              info->port + UART_ESI_TX);
462                 }
463
464                 if (space_avail & 0x0001)
465                         serial_out(info, UART_ESI_TX,
466                                    pio_buf->data[space_avail - 1]);
467
468                 if (info->xmit_cnt) {
469                         serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
470                         serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
471                         space_avail = serial_in(info, UART_ESI_STAT1) << 8;
472                         space_avail |= serial_in(info, UART_ESI_STAT2);
473
474                         if (space_avail > info->xmit_cnt)
475                                 space_avail = info->xmit_cnt;
476                 }
477         }
478
479         if (info->xmit_cnt < WAKEUP_CHARS) {
480                 rs_sched_event(info, ESP_EVENT_WRITE_WAKEUP);
481
482 #ifdef SERIAL_DEBUG_INTR
483                 printk("THRE...");
484 #endif
485
486                 if (info->xmit_cnt <= 0) {
487                         info->IER &= ~UART_IER_THRI;
488                         serial_out(info, UART_ESI_CMD1,
489                                    ESI_SET_SRV_MASK);
490                         serial_out(info, UART_ESI_CMD2, info->IER);
491                 }
492         }
493
494         release_pio_buffer(pio_buf);
495 }
496
497 /* Caller must hold info->lock */
498 static inline void transmit_chars_dma(struct esp_struct *info, int num_bytes)
499 {
500         unsigned long flags;
501         
502         dma_bytes = num_bytes;
503
504         if (info->xmit_tail + dma_bytes <= ESP_XMIT_SIZE) {
505                 memcpy(dma_buffer, &(info->xmit_buf[info->xmit_tail]),
506                        dma_bytes);
507         } else {
508                 int i = ESP_XMIT_SIZE - info->xmit_tail;
509                 memcpy(dma_buffer, &(info->xmit_buf[info->xmit_tail]),
510                         i);
511                 memcpy(&(dma_buffer[i]), info->xmit_buf, dma_bytes - i);
512         }
513
514         info->xmit_cnt -= dma_bytes;
515         info->xmit_tail = (info->xmit_tail + dma_bytes) & (ESP_XMIT_SIZE - 1);
516
517         if (info->xmit_cnt < WAKEUP_CHARS) {
518                 rs_sched_event(info, ESP_EVENT_WRITE_WAKEUP);
519
520 #ifdef SERIAL_DEBUG_INTR
521                 printk("THRE...");
522 #endif
523
524                 if (info->xmit_cnt <= 0) {
525                         info->IER &= ~UART_IER_THRI;
526                         serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
527                         serial_out(info, UART_ESI_CMD2, info->IER);
528                 }
529         }
530
531         info->stat_flags |= ESP_STAT_DMA_TX;
532         
533         flags=claim_dma_lock();
534         disable_dma(dma);
535         clear_dma_ff(dma);
536         set_dma_mode(dma, DMA_MODE_WRITE);
537         set_dma_addr(dma, isa_virt_to_bus(dma_buffer));
538         set_dma_count(dma, dma_bytes);
539         enable_dma(dma);
540         release_dma_lock(flags);
541         
542         serial_out(info, UART_ESI_CMD1, ESI_START_DMA_TX);
543 }
544
545 static inline void transmit_chars_dma_done(struct esp_struct *info)
546 {
547         int num_bytes;
548         unsigned long flags;
549         
550
551         flags=claim_dma_lock();
552         disable_dma(dma);
553         clear_dma_ff(dma);
554
555         num_bytes = dma_bytes - get_dma_residue(dma);
556         info->icount.tx += dma_bytes;
557         release_dma_lock(flags);
558
559         if (dma_bytes != num_bytes) {
560                 dma_bytes -= num_bytes;
561                 memmove(dma_buffer, dma_buffer + num_bytes, dma_bytes);
562                 
563                 flags=claim_dma_lock();
564                 disable_dma(dma);
565                 clear_dma_ff(dma);
566                 set_dma_mode(dma, DMA_MODE_WRITE);
567                 set_dma_addr(dma, isa_virt_to_bus(dma_buffer));
568                 set_dma_count(dma, dma_bytes);
569                 enable_dma(dma);
570                 release_dma_lock(flags);
571                 
572                 serial_out(info, UART_ESI_CMD1, ESI_START_DMA_TX);
573         } else {
574                 dma_bytes = 0;
575                 info->stat_flags &= ~ESP_STAT_DMA_TX;
576         }
577 }
578
579 static inline void check_modem_status(struct esp_struct *info)
580 {
581         int     status;
582         
583         serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
584         status = serial_in(info, UART_ESI_STAT2);
585
586         if (status & UART_MSR_ANY_DELTA) {
587                 /* update input line counters */
588                 if (status & UART_MSR_TERI)
589                         info->icount.rng++;
590                 if (status & UART_MSR_DDSR)
591                         info->icount.dsr++;
592                 if (status & UART_MSR_DDCD)
593                         info->icount.dcd++;
594                 if (status & UART_MSR_DCTS)
595                         info->icount.cts++;
596                 wake_up_interruptible(&info->delta_msr_wait);
597         }
598
599         if ((info->flags & ASYNC_CHECK_CD) && (status & UART_MSR_DDCD)) {
600 #if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
601                 printk("ttys%d CD now %s...", info->line,
602                        (status & UART_MSR_DCD) ? "on" : "off");
603 #endif          
604                 if (status & UART_MSR_DCD)
605                         wake_up_interruptible(&info->open_wait);
606                 else {
607 #ifdef SERIAL_DEBUG_OPEN
608                         printk("scheduling hangup...");
609 #endif
610                         schedule_work(&info->tqueue_hangup);
611                 }
612         }
613 }
614
615 /*
616  * This is the serial driver's interrupt routine
617  */
618 static irqreturn_t rs_interrupt_single(int irq, void *dev_id,
619                                         struct pt_regs *regs)
620 {
621         struct esp_struct * info;
622         unsigned err_status;
623         unsigned int scratch;
624
625 #ifdef SERIAL_DEBUG_INTR
626         printk("rs_interrupt_single(%d)...", irq);
627 #endif
628         info = (struct esp_struct *)dev_id;
629         err_status = 0;
630         scratch = serial_in(info, UART_ESI_SID);
631
632         spin_lock(&info->lock);
633         
634         if (!info->tty) {
635                 spin_unlock(&info->lock);
636                 return IRQ_NONE;
637         }
638
639         if (scratch & 0x04) { /* error */
640                 serial_out(info, UART_ESI_CMD1, ESI_GET_ERR_STAT);
641                 err_status = serial_in(info, UART_ESI_STAT1);
642                 serial_in(info, UART_ESI_STAT2);
643
644                 if (err_status & 0x01)
645                         info->stat_flags |= ESP_STAT_RX_TIMEOUT;
646
647                 if (err_status & 0x20) /* UART status */
648                         check_modem_status(info);
649
650                 if (err_status & 0x80) /* Start break */
651                         wake_up_interruptible(&info->break_wait);
652         }
653                 
654         if ((scratch & 0x88) || /* DMA completed or timed out */
655             (err_status & 0x1c) /* receive error */) {
656                 if (info->stat_flags & ESP_STAT_DMA_RX)
657                         receive_chars_dma_done(info, err_status);
658                 else if (info->stat_flags & ESP_STAT_DMA_TX)
659                         transmit_chars_dma_done(info);
660         }
661
662         if (!(info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) &&
663             ((scratch & 0x01) || (info->stat_flags & ESP_STAT_RX_TIMEOUT)) &&
664             (info->IER & UART_IER_RDI)) {
665                 int num_bytes;
666
667                 serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
668                 serial_out(info, UART_ESI_CMD1, ESI_GET_RX_AVAIL);
669                 num_bytes = serial_in(info, UART_ESI_STAT1) << 8;
670                 num_bytes |= serial_in(info, UART_ESI_STAT2);
671
672                 num_bytes = tty_buffer_request_room(info->tty, num_bytes);
673
674                 if (num_bytes) {
675                         if (dma_bytes ||
676                             (info->stat_flags & ESP_STAT_USE_PIO) ||
677                             (num_bytes <= info->config.pio_threshold))
678                                 receive_chars_pio(info, num_bytes);
679                         else
680                                 receive_chars_dma(info, num_bytes);
681                 }
682         }
683         
684         if (!(info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) &&
685             (scratch & 0x02) && (info->IER & UART_IER_THRI)) {
686                 if ((info->xmit_cnt <= 0) || info->tty->stopped) {
687                         info->IER &= ~UART_IER_THRI;
688                         serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
689                         serial_out(info, UART_ESI_CMD2, info->IER);
690                 } else {
691                         int num_bytes;
692
693                         serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
694                         serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
695                         num_bytes = serial_in(info, UART_ESI_STAT1) << 8;
696                         num_bytes |= serial_in(info, UART_ESI_STAT2);
697
698                         if (num_bytes > info->xmit_cnt)
699                                 num_bytes = info->xmit_cnt;
700
701                         if (num_bytes) {
702                                 if (dma_bytes ||
703                                     (info->stat_flags & ESP_STAT_USE_PIO) ||
704                                     (num_bytes <= info->config.pio_threshold))
705                                         transmit_chars_pio(info, num_bytes);
706                                 else
707                                         transmit_chars_dma(info, num_bytes);
708                         }
709                 }
710         }
711
712         info->last_active = jiffies;
713
714 #ifdef SERIAL_DEBUG_INTR
715         printk("end.\n");
716 #endif
717         spin_unlock(&info->lock);
718         return IRQ_HANDLED;
719 }
720
721 /*
722  * -------------------------------------------------------------------
723  * Here ends the serial interrupt routines.
724  * -------------------------------------------------------------------
725  */
726
727 static void do_softint(void *private_)
728 {
729         struct esp_struct       *info = (struct esp_struct *) private_;
730         struct tty_struct       *tty;
731         
732         tty = info->tty;
733         if (!tty)
734                 return;
735
736         if (test_and_clear_bit(ESP_EVENT_WRITE_WAKEUP, &info->event)) {
737                 tty_wakeup(tty);
738         }
739 }
740
741 /*
742  * This routine is called from the scheduler tqueue when the interrupt
743  * routine has signalled that a hangup has occurred.  The path of
744  * hangup processing is:
745  *
746  *      serial interrupt routine -> (scheduler tqueue) ->
747  *      do_serial_hangup() -> tty->hangup() -> esp_hangup()
748  * 
749  */
750 static void do_serial_hangup(void *private_)
751 {
752         struct esp_struct       *info = (struct esp_struct *) private_;
753         struct tty_struct       *tty;
754         
755         tty = info->tty;
756         if (tty)
757                 tty_hangup(tty);
758 }
759
760 /*
761  * ---------------------------------------------------------------
762  * Low level utility subroutines for the serial driver:  routines to
763  * figure out the appropriate timeout for an interrupt chain, routines
764  * to initialize and startup a serial port, and routines to shutdown a
765  * serial port.  Useful stuff like that.
766  *
767  * Caller should hold lock
768  * ---------------------------------------------------------------
769  */
770
771 static inline void esp_basic_init(struct esp_struct * info)
772 {
773         /* put ESPC in enhanced mode */
774         serial_out(info, UART_ESI_CMD1, ESI_SET_MODE);
775         
776         if (info->stat_flags & ESP_STAT_NEVER_DMA)
777                 serial_out(info, UART_ESI_CMD2, 0x01);
778         else
779                 serial_out(info, UART_ESI_CMD2, 0x31);
780
781         /* disable interrupts for now */
782         serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
783         serial_out(info, UART_ESI_CMD2, 0x00);
784
785         /* set interrupt and DMA channel */
786         serial_out(info, UART_ESI_CMD1, ESI_SET_IRQ);
787
788         if (info->stat_flags & ESP_STAT_NEVER_DMA)
789                 serial_out(info, UART_ESI_CMD2, 0x01);
790         else
791                 serial_out(info, UART_ESI_CMD2, (dma << 4) | 0x01);
792
793         serial_out(info, UART_ESI_CMD1, ESI_SET_ENH_IRQ);
794
795         if (info->line % 8)     /* secondary port */
796                 serial_out(info, UART_ESI_CMD2, 0x0d);  /* shared */
797         else if (info->irq == 9)
798                 serial_out(info, UART_ESI_CMD2, 0x02);
799         else
800                 serial_out(info, UART_ESI_CMD2, info->irq);
801
802         /* set error status mask (check this) */
803         serial_out(info, UART_ESI_CMD1, ESI_SET_ERR_MASK);
804
805         if (info->stat_flags & ESP_STAT_NEVER_DMA)
806                 serial_out(info, UART_ESI_CMD2, 0xa1);
807         else
808                 serial_out(info, UART_ESI_CMD2, 0xbd);
809
810         serial_out(info, UART_ESI_CMD2, 0x00);
811
812         /* set DMA timeout */
813         serial_out(info, UART_ESI_CMD1, ESI_SET_DMA_TMOUT);
814         serial_out(info, UART_ESI_CMD2, 0xff);
815
816         /* set FIFO trigger levels */
817         serial_out(info, UART_ESI_CMD1, ESI_SET_TRIGGER);
818         serial_out(info, UART_ESI_CMD2, info->config.rx_trigger >> 8);
819         serial_out(info, UART_ESI_CMD2, info->config.rx_trigger);
820         serial_out(info, UART_ESI_CMD2, info->config.tx_trigger >> 8);
821         serial_out(info, UART_ESI_CMD2, info->config.tx_trigger);
822
823         /* Set clock scaling and wait states */
824         serial_out(info, UART_ESI_CMD1, ESI_SET_PRESCALAR);
825         serial_out(info, UART_ESI_CMD2, 0x04 | ESPC_SCALE);
826
827         /* set reinterrupt pacing */
828         serial_out(info, UART_ESI_CMD1, ESI_SET_REINTR);
829         serial_out(info, UART_ESI_CMD2, 0xff);
830 }
831
832 static int startup(struct esp_struct * info)
833 {
834         unsigned long flags;
835         int     retval=0;
836         unsigned int num_chars;
837
838         spin_lock_irqsave(&info->lock, flags);
839
840         if (info->flags & ASYNC_INITIALIZED)
841                 goto out;
842
843         if (!info->xmit_buf) {
844                 info->xmit_buf = (unsigned char *)get_zeroed_page(GFP_ATOMIC);
845                 retval = -ENOMEM;
846                 if (!info->xmit_buf)
847                         goto out;
848         }
849
850 #ifdef SERIAL_DEBUG_OPEN
851         printk("starting up ttys%d (irq %d)...", info->line, info->irq);
852 #endif
853
854         /* Flush the RX buffer.  Using the ESI flush command may cause */
855         /* wild interrupts, so read all the data instead. */
856
857         serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
858         serial_out(info, UART_ESI_CMD1, ESI_GET_RX_AVAIL);
859         num_chars = serial_in(info, UART_ESI_STAT1) << 8;
860         num_chars |= serial_in(info, UART_ESI_STAT2);
861
862         while (num_chars > 1) {
863                 inw(info->port + UART_ESI_RX);
864                 num_chars -= 2;
865         }
866
867         if (num_chars)
868                 serial_in(info, UART_ESI_RX);
869
870         /* set receive character timeout */
871         serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
872         serial_out(info, UART_ESI_CMD2, info->config.rx_timeout);
873
874         /* clear all flags except the "never DMA" flag */
875         info->stat_flags &= ESP_STAT_NEVER_DMA;
876
877         if (info->stat_flags & ESP_STAT_NEVER_DMA)
878                 info->stat_flags |= ESP_STAT_USE_PIO;
879
880         spin_unlock_irqrestore(&info->lock, flags);
881
882         /*
883          * Allocate the IRQ
884          */
885
886         retval = request_irq(info->irq, rs_interrupt_single, SA_SHIRQ,
887                              "esp serial", info);
888
889         if (retval) {
890                 if (capable(CAP_SYS_ADMIN)) {
891                         if (info->tty)
892                                 set_bit(TTY_IO_ERROR,
893                                         &info->tty->flags);
894                         retval = 0;
895                 }
896                 goto out_unlocked;
897         }
898
899         if (!(info->stat_flags & ESP_STAT_USE_PIO) && !dma_buffer) {
900                 dma_buffer = (char *)__get_dma_pages(
901                         GFP_KERNEL, get_order(DMA_BUFFER_SZ));
902
903                 /* use PIO mode if DMA buf/chan cannot be allocated */
904                 if (!dma_buffer)
905                         info->stat_flags |= ESP_STAT_USE_PIO;
906                 else if (request_dma(dma, "esp serial")) {
907                         free_pages((unsigned long)dma_buffer,
908                                    get_order(DMA_BUFFER_SZ));
909                         dma_buffer = NULL;
910                         info->stat_flags |= ESP_STAT_USE_PIO;
911                 }
912                         
913         }
914
915         info->MCR = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2;
916
917         spin_lock_irqsave(&info->lock, flags);
918         serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
919         serial_out(info, UART_ESI_CMD2, UART_MCR);
920         serial_out(info, UART_ESI_CMD2, info->MCR);
921         
922         /*
923          * Finally, enable interrupts
924          */
925         /* info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI; */
926         info->IER = UART_IER_RLSI | UART_IER_RDI | UART_IER_DMA_TMOUT |
927                         UART_IER_DMA_TC;
928         serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
929         serial_out(info, UART_ESI_CMD2, info->IER);
930         
931         if (info->tty)
932                 clear_bit(TTY_IO_ERROR, &info->tty->flags);
933         info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
934         spin_unlock_irqrestore(&info->lock, flags);
935
936         /*
937          * Set up the tty->alt_speed kludge
938          */
939         if (info->tty) {
940                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
941                         info->tty->alt_speed = 57600;
942                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
943                         info->tty->alt_speed = 115200;
944                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
945                         info->tty->alt_speed = 230400;
946                 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
947                         info->tty->alt_speed = 460800;
948         }
949         
950         /*
951          * set the speed of the serial port
952          */
953         change_speed(info);
954         info->flags |= ASYNC_INITIALIZED;
955         return 0;
956
957 out:
958         spin_unlock_irqrestore(&info->lock, flags);
959 out_unlocked:
960         return retval;
961 }
962
963 /*
964  * This routine will shutdown a serial port; interrupts are disabled, and
965  * DTR is dropped if the hangup on close termio flag is on.
966  */
967 static void shutdown(struct esp_struct * info)
968 {
969         unsigned long   flags, f;
970
971         if (!(info->flags & ASYNC_INITIALIZED))
972                 return;
973
974 #ifdef SERIAL_DEBUG_OPEN
975         printk("Shutting down serial port %d (irq %d)....", info->line,
976                info->irq);
977 #endif
978         
979         spin_lock_irqsave(&info->lock, flags);
980         /*
981          * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
982          * here so the queue might never be waken up
983          */
984         wake_up_interruptible(&info->delta_msr_wait);
985         wake_up_interruptible(&info->break_wait);
986
987         /* stop a DMA transfer on the port being closed */
988         /* DMA lock is higher priority always */
989         if (info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) {
990                 f=claim_dma_lock();
991                 disable_dma(dma);
992                 clear_dma_ff(dma);
993                 release_dma_lock(f);
994                 
995                 dma_bytes = 0;
996         }
997         
998         /*
999          * Free the IRQ
1000          */
1001         free_irq(info->irq, info);
1002
1003         if (dma_buffer) {
1004                 struct esp_struct *current_port = ports;
1005
1006                 while (current_port) {
1007                         if ((current_port != info) &&
1008                             (current_port->flags & ASYNC_INITIALIZED))
1009                                 break;
1010
1011                         current_port = current_port->next_port;
1012                 }
1013
1014                 if (!current_port) {
1015                         free_dma(dma);
1016                         free_pages((unsigned long)dma_buffer,
1017                                    get_order(DMA_BUFFER_SZ));
1018                         dma_buffer = NULL;
1019                 }               
1020         }
1021
1022         if (info->xmit_buf) {
1023                 free_page((unsigned long) info->xmit_buf);
1024                 info->xmit_buf = NULL;
1025         }
1026
1027         info->IER = 0;
1028         serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1029         serial_out(info, UART_ESI_CMD2, 0x00);
1030
1031         if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
1032                 info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
1033
1034         info->MCR &= ~UART_MCR_OUT2;
1035         serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1036         serial_out(info, UART_ESI_CMD2, UART_MCR);
1037         serial_out(info, UART_ESI_CMD2, info->MCR);
1038
1039         if (info->tty)
1040                 set_bit(TTY_IO_ERROR, &info->tty->flags);
1041         
1042         info->flags &= ~ASYNC_INITIALIZED;
1043         spin_unlock_irqrestore(&info->lock, flags);
1044 }
1045
1046 /*
1047  * This routine is called to set the UART divisor registers to match
1048  * the specified baud rate for a serial port.
1049  */
1050 static void change_speed(struct esp_struct *info)
1051 {
1052         unsigned short port;
1053         int     quot = 0;
1054         unsigned cflag,cval;
1055         int     baud, bits;
1056         unsigned char flow1 = 0, flow2 = 0;
1057         unsigned long flags;
1058
1059         if (!info->tty || !info->tty->termios)
1060                 return;
1061         cflag = info->tty->termios->c_cflag;
1062         port = info->port;
1063         
1064         /* byte size and parity */
1065         switch (cflag & CSIZE) {
1066               case CS5: cval = 0x00; bits = 7; break;
1067               case CS6: cval = 0x01; bits = 8; break;
1068               case CS7: cval = 0x02; bits = 9; break;
1069               case CS8: cval = 0x03; bits = 10; break;
1070               default:  cval = 0x00; bits = 7; break;
1071         }
1072         if (cflag & CSTOPB) {
1073                 cval |= 0x04;
1074                 bits++;
1075         }
1076         if (cflag & PARENB) {
1077                 cval |= UART_LCR_PARITY;
1078                 bits++;
1079         }
1080         if (!(cflag & PARODD))
1081                 cval |= UART_LCR_EPAR;
1082 #ifdef CMSPAR
1083         if (cflag & CMSPAR)
1084                 cval |= UART_LCR_SPAR;
1085 #endif
1086
1087         baud = tty_get_baud_rate(info->tty);
1088         if (baud == 38400 &&
1089             ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
1090                 quot = info->custom_divisor;
1091         else {
1092                 if (baud == 134)
1093                         /* Special case since 134 is really 134.5 */
1094                         quot = (2*BASE_BAUD / 269);
1095                 else if (baud)
1096                         quot = BASE_BAUD / baud;
1097         }
1098         /* If the quotient is ever zero, default to 9600 bps */
1099         if (!quot)
1100                 quot = BASE_BAUD / 9600;
1101         
1102         info->timeout = ((1024 * HZ * bits * quot) / BASE_BAUD) + (HZ / 50);
1103
1104         /* CTS flow control flag and modem status interrupts */
1105         /* info->IER &= ~UART_IER_MSI; */
1106         if (cflag & CRTSCTS) {
1107                 info->flags |= ASYNC_CTS_FLOW;
1108                 /* info->IER |= UART_IER_MSI; */
1109                 flow1 = 0x04;
1110                 flow2 = 0x10;
1111         } else
1112                 info->flags &= ~ASYNC_CTS_FLOW;
1113         if (cflag & CLOCAL)
1114                 info->flags &= ~ASYNC_CHECK_CD;
1115         else {
1116                 info->flags |= ASYNC_CHECK_CD;
1117                 /* info->IER |= UART_IER_MSI; */
1118         }
1119
1120         /*
1121          * Set up parity check flag
1122          */
1123 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
1124
1125         info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
1126         if (I_INPCK(info->tty))
1127                 info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
1128         if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
1129                 info->read_status_mask |= UART_LSR_BI;
1130         
1131         info->ignore_status_mask = 0;
1132 #if 0
1133         /* This should be safe, but for some broken bits of hardware... */
1134         if (I_IGNPAR(info->tty)) {
1135                 info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
1136                 info->read_status_mask |= UART_LSR_PE | UART_LSR_FE;
1137         }
1138 #endif
1139         if (I_IGNBRK(info->tty)) {
1140                 info->ignore_status_mask |= UART_LSR_BI;
1141                 info->read_status_mask |= UART_LSR_BI;
1142                 /*
1143                  * If we're ignore parity and break indicators, ignore 
1144                  * overruns too.  (For real raw support).
1145                  */
1146                 if (I_IGNPAR(info->tty)) {
1147                         info->ignore_status_mask |= UART_LSR_OE | \
1148                                 UART_LSR_PE | UART_LSR_FE;
1149                         info->read_status_mask |= UART_LSR_OE | \
1150                                 UART_LSR_PE | UART_LSR_FE;
1151                 }
1152         }
1153
1154         if (I_IXOFF(info->tty))
1155                 flow1 |= 0x81;
1156
1157         spin_lock_irqsave(&info->lock, flags);
1158         /* set baud */
1159         serial_out(info, UART_ESI_CMD1, ESI_SET_BAUD);
1160         serial_out(info, UART_ESI_CMD2, quot >> 8);
1161         serial_out(info, UART_ESI_CMD2, quot & 0xff);
1162
1163         /* set data bits, parity, etc. */
1164         serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1165         serial_out(info, UART_ESI_CMD2, UART_LCR);
1166         serial_out(info, UART_ESI_CMD2, cval);
1167
1168         /* Enable flow control */
1169         serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_CNTL);
1170         serial_out(info, UART_ESI_CMD2, flow1);
1171         serial_out(info, UART_ESI_CMD2, flow2);
1172
1173         /* set flow control characters (XON/XOFF only) */
1174         if (I_IXOFF(info->tty)) {
1175                 serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_CHARS);
1176                 serial_out(info, UART_ESI_CMD2, START_CHAR(info->tty));
1177                 serial_out(info, UART_ESI_CMD2, STOP_CHAR(info->tty));
1178                 serial_out(info, UART_ESI_CMD2, 0x10);
1179                 serial_out(info, UART_ESI_CMD2, 0x21);
1180                 switch (cflag & CSIZE) {
1181                         case CS5:
1182                                 serial_out(info, UART_ESI_CMD2, 0x1f);
1183                                 break;
1184                         case CS6:
1185                                 serial_out(info, UART_ESI_CMD2, 0x3f);
1186                                 break;
1187                         case CS7:
1188                         case CS8:
1189                                 serial_out(info, UART_ESI_CMD2, 0x7f);
1190                                 break;
1191                         default:
1192                                 serial_out(info, UART_ESI_CMD2, 0xff);
1193                                 break;
1194                 }
1195         }
1196
1197         /* Set high/low water */
1198         serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_LVL);
1199         serial_out(info, UART_ESI_CMD2, info->config.flow_off >> 8);
1200         serial_out(info, UART_ESI_CMD2, info->config.flow_off);
1201         serial_out(info, UART_ESI_CMD2, info->config.flow_on >> 8);
1202         serial_out(info, UART_ESI_CMD2, info->config.flow_on);
1203
1204         spin_unlock_irqrestore(&info->lock, flags);
1205 }
1206
1207 static void rs_put_char(struct tty_struct *tty, unsigned char ch)
1208 {
1209         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1210         unsigned long flags;
1211
1212         if (serial_paranoia_check(info, tty->name, "rs_put_char"))
1213                 return;
1214
1215         if (!tty || !info->xmit_buf)
1216                 return;
1217
1218         spin_lock_irqsave(&info->lock, flags);
1219         if (info->xmit_cnt < ESP_XMIT_SIZE - 1) {
1220                 info->xmit_buf[info->xmit_head++] = ch;
1221                 info->xmit_head &= ESP_XMIT_SIZE-1;
1222                 info->xmit_cnt++;
1223         }
1224         spin_unlock_irqrestore(&info->lock, flags);
1225 }
1226
1227 static void rs_flush_chars(struct tty_struct *tty)
1228 {
1229         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1230         unsigned long flags;
1231                                 
1232         if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
1233                 return;
1234
1235         spin_lock_irqsave(&info->lock, flags);
1236
1237         if (info->xmit_cnt <= 0 || tty->stopped || !info->xmit_buf)
1238                 goto out;
1239
1240         if (!(info->IER & UART_IER_THRI)) {
1241                 info->IER |= UART_IER_THRI;
1242                 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1243                 serial_out(info, UART_ESI_CMD2, info->IER);
1244         }
1245 out:
1246         spin_unlock_irqrestore(&info->lock, flags);
1247 }
1248
1249 static int rs_write(struct tty_struct * tty,
1250                     const unsigned char *buf, int count)
1251 {
1252         int     c, t, ret = 0;
1253         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1254         unsigned long flags;
1255
1256         if (serial_paranoia_check(info, tty->name, "rs_write"))
1257                 return 0;
1258
1259         if (!tty || !info->xmit_buf)
1260                 return 0;
1261             
1262         while (1) {
1263                 /* Thanks to R. Wolff for suggesting how to do this with */
1264                 /* interrupts enabled */
1265
1266                 c = count;
1267                 t = ESP_XMIT_SIZE - info->xmit_cnt - 1;
1268                 
1269                 if (t < c)
1270                         c = t;
1271
1272                 t = ESP_XMIT_SIZE - info->xmit_head;
1273                 
1274                 if (t < c)
1275                         c = t;
1276
1277                 if (c <= 0)
1278                         break;
1279
1280                 memcpy(info->xmit_buf + info->xmit_head, buf, c);
1281
1282                 info->xmit_head = (info->xmit_head + c) & (ESP_XMIT_SIZE-1);
1283                 info->xmit_cnt += c;
1284                 buf += c;
1285                 count -= c;
1286                 ret += c;
1287         }
1288
1289         spin_lock_irqsave(&info->lock, flags);
1290
1291         if (info->xmit_cnt && !tty->stopped && !(info->IER & UART_IER_THRI)) {
1292                 info->IER |= UART_IER_THRI;
1293                 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1294                 serial_out(info, UART_ESI_CMD2, info->IER);
1295         }
1296
1297         spin_unlock_irqrestore(&info->lock, flags);
1298         return ret;
1299 }
1300
1301 static int rs_write_room(struct tty_struct *tty)
1302 {
1303         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1304         int     ret;
1305         unsigned long flags;
1306                                 
1307         if (serial_paranoia_check(info, tty->name, "rs_write_room"))
1308                 return 0;
1309
1310         spin_lock_irqsave(&info->lock, flags);
1311
1312         ret = ESP_XMIT_SIZE - info->xmit_cnt - 1;
1313         if (ret < 0)
1314                 ret = 0;
1315         spin_unlock_irqrestore(&info->lock, flags);
1316         return ret;
1317 }
1318
1319 static int rs_chars_in_buffer(struct tty_struct *tty)
1320 {
1321         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1322                                 
1323         if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
1324                 return 0;
1325         return info->xmit_cnt;
1326 }
1327
1328 static void rs_flush_buffer(struct tty_struct *tty)
1329 {
1330         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1331         unsigned long flags;
1332                                 
1333         if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
1334                 return;
1335         spin_lock_irqsave(&info->lock, flags);
1336         info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
1337         spin_unlock_irqrestore(&info->lock, flags);
1338         tty_wakeup(tty);
1339 }
1340
1341 /*
1342  * ------------------------------------------------------------
1343  * rs_throttle()
1344  * 
1345  * This routine is called by the upper-layer tty layer to signal that
1346  * incoming characters should be throttled.
1347  * ------------------------------------------------------------
1348  */
1349 static void rs_throttle(struct tty_struct * tty)
1350 {
1351         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1352         unsigned long flags;
1353 #ifdef SERIAL_DEBUG_THROTTLE
1354         char    buf[64];
1355         
1356         printk("throttle %s: %d....\n", tty_name(tty, buf),
1357                tty->ldisc.chars_in_buffer(tty));
1358 #endif
1359
1360         if (serial_paranoia_check(info, tty->name, "rs_throttle"))
1361                 return;
1362
1363         spin_lock_irqsave(&info->lock, flags);
1364         info->IER &= ~UART_IER_RDI;
1365         serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1366         serial_out(info, UART_ESI_CMD2, info->IER);
1367         serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
1368         serial_out(info, UART_ESI_CMD2, 0x00);
1369         spin_unlock_irqrestore(&info->lock, flags);
1370 }
1371
1372 static void rs_unthrottle(struct tty_struct * tty)
1373 {
1374         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1375         unsigned long flags;
1376 #ifdef SERIAL_DEBUG_THROTTLE
1377         char    buf[64];
1378         
1379         printk("unthrottle %s: %d....\n", tty_name(tty, buf),
1380                tty->ldisc.chars_in_buffer(tty));
1381 #endif
1382
1383         if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
1384                 return;
1385         
1386         spin_lock_irqsave(&info->lock, flags);
1387         info->IER |= UART_IER_RDI;
1388         serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1389         serial_out(info, UART_ESI_CMD2, info->IER);
1390         serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
1391         serial_out(info, UART_ESI_CMD2, info->config.rx_timeout);
1392         spin_unlock_irqrestore(&info->lock, flags);
1393 }
1394
1395 /*
1396  * ------------------------------------------------------------
1397  * rs_ioctl() and friends
1398  * ------------------------------------------------------------
1399  */
1400
1401 static int get_serial_info(struct esp_struct * info,
1402                            struct serial_struct __user *retinfo)
1403 {
1404         struct serial_struct tmp;
1405   
1406         memset(&tmp, 0, sizeof(tmp));
1407         tmp.type = PORT_16550A;
1408         tmp.line = info->line;
1409         tmp.port = info->port;
1410         tmp.irq = info->irq;
1411         tmp.flags = info->flags;
1412         tmp.xmit_fifo_size = 1024;
1413         tmp.baud_base = BASE_BAUD;
1414         tmp.close_delay = info->close_delay;
1415         tmp.closing_wait = info->closing_wait;
1416         tmp.custom_divisor = info->custom_divisor;
1417         tmp.hub6 = 0;
1418         if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
1419                 return -EFAULT;
1420         return 0;
1421 }
1422
1423 static int get_esp_config(struct esp_struct * info,
1424                           struct hayes_esp_config __user *retinfo)
1425 {
1426         struct hayes_esp_config tmp;
1427   
1428         if (!retinfo)
1429                 return -EFAULT;
1430
1431         memset(&tmp, 0, sizeof(tmp));
1432         tmp.rx_timeout = info->config.rx_timeout;
1433         tmp.rx_trigger = info->config.rx_trigger;
1434         tmp.tx_trigger = info->config.tx_trigger;
1435         tmp.flow_off = info->config.flow_off;
1436         tmp.flow_on = info->config.flow_on;
1437         tmp.pio_threshold = info->config.pio_threshold;
1438         tmp.dma_channel = (info->stat_flags & ESP_STAT_NEVER_DMA ? 0 : dma);
1439
1440         return copy_to_user(retinfo, &tmp, sizeof(*retinfo)) ? -EFAULT : 0;
1441 }
1442
1443 static int set_serial_info(struct esp_struct * info,
1444                            struct serial_struct __user *new_info)
1445 {
1446         struct serial_struct new_serial;
1447         struct esp_struct old_info;
1448         unsigned int change_irq;
1449         int retval = 0;
1450         struct esp_struct *current_async;
1451
1452         if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
1453                 return -EFAULT;
1454         old_info = *info;
1455
1456         if ((new_serial.type != PORT_16550A) ||
1457             (new_serial.hub6) ||
1458             (info->port != new_serial.port) ||
1459             (new_serial.baud_base != BASE_BAUD) ||
1460             (new_serial.irq > 15) ||
1461             (new_serial.irq < 2) ||
1462             (new_serial.irq == 6) ||
1463             (new_serial.irq == 8) ||
1464             (new_serial.irq == 13))
1465                 return -EINVAL;
1466
1467         change_irq = new_serial.irq != info->irq;
1468
1469         if (change_irq && (info->line % 8))
1470                 return -EINVAL;
1471
1472         if (!capable(CAP_SYS_ADMIN)) {
1473                 if (change_irq || 
1474                     (new_serial.close_delay != info->close_delay) ||
1475                     ((new_serial.flags & ~ASYNC_USR_MASK) !=
1476                      (info->flags & ~ASYNC_USR_MASK)))
1477                         return -EPERM;
1478                 info->flags = ((info->flags & ~ASYNC_USR_MASK) |
1479                                (new_serial.flags & ASYNC_USR_MASK));
1480                 info->custom_divisor = new_serial.custom_divisor;
1481         } else {
1482                 if (new_serial.irq == 2)
1483                         new_serial.irq = 9;
1484
1485                 if (change_irq) {
1486                         current_async = ports;
1487
1488                         while (current_async) {
1489                                 if ((current_async->line >= info->line) &&
1490                                     (current_async->line < (info->line + 8))) {
1491                                         if (current_async == info) {
1492                                                 if (current_async->count > 1)
1493                                                         return -EBUSY;
1494                                         } else if (current_async->count)
1495                                                 return -EBUSY;
1496                                 }
1497
1498                                 current_async = current_async->next_port;
1499                         }
1500                 }
1501
1502                 /*
1503                  * OK, past this point, all the error checking has been done.
1504                  * At this point, we start making changes.....
1505                  */
1506
1507                 info->flags = ((info->flags & ~ASYNC_FLAGS) |
1508                                (new_serial.flags & ASYNC_FLAGS));
1509                 info->custom_divisor = new_serial.custom_divisor;
1510                 info->close_delay = new_serial.close_delay * HZ/100;
1511                 info->closing_wait = new_serial.closing_wait * HZ/100;
1512
1513                 if (change_irq) {
1514                         /*
1515                          * We need to shutdown the serial port at the old
1516                          * port/irq combination.
1517                          */
1518                         shutdown(info);
1519
1520                         current_async = ports;
1521
1522                         while (current_async) {
1523                                 if ((current_async->line >= info->line) &&
1524                                     (current_async->line < (info->line + 8)))
1525                                         current_async->irq = new_serial.irq;
1526
1527                                 current_async = current_async->next_port;
1528                         }
1529
1530                         serial_out(info, UART_ESI_CMD1, ESI_SET_ENH_IRQ);
1531                         if (info->irq == 9)
1532                                 serial_out(info, UART_ESI_CMD2, 0x02);
1533                         else
1534                                 serial_out(info, UART_ESI_CMD2, info->irq);
1535                 }
1536         }
1537
1538         if (info->flags & ASYNC_INITIALIZED) {
1539                 if (((old_info.flags & ASYNC_SPD_MASK) !=
1540                      (info->flags & ASYNC_SPD_MASK)) ||
1541                     (old_info.custom_divisor != info->custom_divisor)) {
1542                         if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
1543                                 info->tty->alt_speed = 57600;
1544                         if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
1545                                 info->tty->alt_speed = 115200;
1546                         if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
1547                                 info->tty->alt_speed = 230400;
1548                         if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
1549                                 info->tty->alt_speed = 460800;
1550                         change_speed(info);
1551                 }
1552         } else
1553                 retval = startup(info);
1554
1555         return retval;
1556 }
1557
1558 static int set_esp_config(struct esp_struct * info,
1559                           struct hayes_esp_config __user * new_info)
1560 {
1561         struct hayes_esp_config new_config;
1562         unsigned int change_dma;
1563         int retval = 0;
1564         struct esp_struct *current_async;
1565         unsigned long flags;
1566
1567         /* Perhaps a non-sysadmin user should be able to do some of these */
1568         /* operations.  I haven't decided yet. */
1569
1570         if (!capable(CAP_SYS_ADMIN))
1571                 return -EPERM;
1572
1573         if (copy_from_user(&new_config, new_info, sizeof(new_config)))
1574                 return -EFAULT;
1575
1576         if ((new_config.flow_on >= new_config.flow_off) ||
1577             (new_config.rx_trigger < 1) ||
1578             (new_config.tx_trigger < 1) ||
1579             (new_config.flow_off < 1) ||
1580             (new_config.flow_on < 1) ||
1581             (new_config.rx_trigger > 1023) ||
1582             (new_config.tx_trigger > 1023) ||
1583             (new_config.flow_off > 1023) ||
1584             (new_config.flow_on > 1023) ||
1585             (new_config.pio_threshold < 0) ||
1586             (new_config.pio_threshold > 1024))
1587                 return -EINVAL;
1588
1589         if ((new_config.dma_channel != 1) && (new_config.dma_channel != 3))
1590                 new_config.dma_channel = 0;
1591
1592         if (info->stat_flags & ESP_STAT_NEVER_DMA)
1593                 change_dma = new_config.dma_channel;
1594         else
1595                 change_dma = (new_config.dma_channel != dma);
1596
1597         if (change_dma) {
1598                 if (new_config.dma_channel) {
1599                         /* PIO mode to DMA mode transition OR */
1600                         /* change current DMA channel */
1601                         
1602                         current_async = ports;
1603
1604                         while (current_async) {
1605                                 if (current_async == info) {
1606                                         if (current_async->count > 1)
1607                                                 return -EBUSY;
1608                                 } else if (current_async->count)
1609                                         return -EBUSY;
1610                                         
1611                                 current_async =
1612                                         current_async->next_port;
1613                         }
1614
1615                         shutdown(info);
1616                         dma = new_config.dma_channel;
1617                         info->stat_flags &= ~ESP_STAT_NEVER_DMA;
1618                         
1619                         /* all ports must use the same DMA channel */
1620
1621                         spin_lock_irqsave(&info->lock, flags);
1622                         current_async = ports;
1623
1624                         while (current_async) {
1625                                 esp_basic_init(current_async);
1626                                 current_async = current_async->next_port;
1627                         }
1628                         spin_unlock_irqrestore(&info->lock, flags);
1629                 } else {
1630                         /* DMA mode to PIO mode only */
1631                         
1632                         if (info->count > 1)
1633                                 return -EBUSY;
1634
1635                         shutdown(info);
1636                         spin_lock_irqsave(&info->lock, flags);
1637                         info->stat_flags |= ESP_STAT_NEVER_DMA;
1638                         esp_basic_init(info);
1639                         spin_unlock_irqrestore(&info->lock, flags);
1640                 }
1641         }
1642
1643         info->config.pio_threshold = new_config.pio_threshold;
1644
1645         if ((new_config.flow_off != info->config.flow_off) ||
1646             (new_config.flow_on != info->config.flow_on)) {
1647                 unsigned long flags;
1648
1649                 info->config.flow_off = new_config.flow_off;
1650                 info->config.flow_on = new_config.flow_on;
1651
1652                 spin_lock_irqsave(&info->lock, flags);
1653                 serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_LVL);
1654                 serial_out(info, UART_ESI_CMD2, new_config.flow_off >> 8);
1655                 serial_out(info, UART_ESI_CMD2, new_config.flow_off);
1656                 serial_out(info, UART_ESI_CMD2, new_config.flow_on >> 8);
1657                 serial_out(info, UART_ESI_CMD2, new_config.flow_on);
1658                 spin_unlock_irqrestore(&info->lock, flags);
1659         }
1660
1661         if ((new_config.rx_trigger != info->config.rx_trigger) ||
1662             (new_config.tx_trigger != info->config.tx_trigger)) {
1663                 unsigned long flags;
1664
1665                 info->config.rx_trigger = new_config.rx_trigger;
1666                 info->config.tx_trigger = new_config.tx_trigger;
1667                 spin_lock_irqsave(&info->lock, flags);
1668                 serial_out(info, UART_ESI_CMD1, ESI_SET_TRIGGER);
1669                 serial_out(info, UART_ESI_CMD2,
1670                            new_config.rx_trigger >> 8);
1671                 serial_out(info, UART_ESI_CMD2, new_config.rx_trigger);
1672                 serial_out(info, UART_ESI_CMD2,
1673                            new_config.tx_trigger >> 8);
1674                 serial_out(info, UART_ESI_CMD2, new_config.tx_trigger);
1675                 spin_unlock_irqrestore(&info->lock, flags);
1676         }
1677
1678         if (new_config.rx_timeout != info->config.rx_timeout) {
1679                 unsigned long flags;
1680
1681                 info->config.rx_timeout = new_config.rx_timeout;
1682                 spin_lock_irqsave(&info->lock, flags);
1683
1684                 if (info->IER & UART_IER_RDI) {
1685                         serial_out(info, UART_ESI_CMD1,
1686                                    ESI_SET_RX_TIMEOUT);
1687                         serial_out(info, UART_ESI_CMD2,
1688                                    new_config.rx_timeout);
1689                 }
1690
1691                 spin_unlock_irqrestore(&info->lock, flags);
1692         }
1693
1694         if (!(info->flags & ASYNC_INITIALIZED))
1695                 retval = startup(info);
1696
1697         return retval;
1698 }
1699
1700 /*
1701  * get_lsr_info - get line status register info
1702  *
1703  * Purpose: Let user call ioctl() to get info when the UART physically
1704  *          is emptied.  On bus types like RS485, the transmitter must
1705  *          release the bus after transmitting. This must be done when
1706  *          the transmit shift register is empty, not be done when the
1707  *          transmit holding register is empty.  This functionality
1708  *          allows an RS485 driver to be written in user space. 
1709  */
1710 static int get_lsr_info(struct esp_struct * info, unsigned int __user *value)
1711 {
1712         unsigned char status;
1713         unsigned int result;
1714         unsigned long flags;
1715
1716         spin_lock_irqsave(&info->lock, flags);
1717         serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
1718         status = serial_in(info, UART_ESI_STAT1);
1719         spin_unlock_irqrestore(&info->lock, flags);
1720         result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
1721         return put_user(result,value);
1722 }
1723
1724
1725 static int esp_tiocmget(struct tty_struct *tty, struct file *file)
1726 {
1727         struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1728         unsigned char control, status;
1729         unsigned long flags;
1730
1731         if (serial_paranoia_check(info, tty->name, __FUNCTION__))
1732                 return -ENODEV;
1733         if (tty->flags & (1 << TTY_IO_ERROR))
1734                 return -EIO;
1735
1736         control = info->MCR;
1737
1738         spin_lock_irqsave(&info->lock, flags);
1739         serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
1740         status = serial_in(info, UART_ESI_STAT2);
1741         spin_unlock_irqrestore(&info->lock, flags);
1742
1743         return    ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
1744                 | ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
1745                 | ((status  & UART_MSR_DCD) ? TIOCM_CAR : 0)
1746                 | ((status  & UART_MSR_RI) ? TIOCM_RNG : 0)
1747                 | ((status  & UART_MSR_DSR) ? TIOCM_DSR : 0)
1748                 | ((status  & UART_MSR_CTS) ? TIOCM_CTS : 0);
1749 }
1750
1751 static int esp_tiocmset(struct tty_struct *tty, struct file *file,
1752                         unsigned int set, unsigned int clear)
1753 {
1754         struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1755         unsigned long flags;
1756
1757         if (serial_paranoia_check(info, tty->name, __FUNCTION__))
1758                 return -ENODEV;
1759         if (tty->flags & (1 << TTY_IO_ERROR))
1760                 return -EIO;
1761
1762         spin_lock_irqsave(&info->lock, flags);
1763
1764         if (set & TIOCM_RTS)
1765                 info->MCR |= UART_MCR_RTS;
1766         if (set & TIOCM_DTR)
1767                 info->MCR |= UART_MCR_DTR;
1768
1769         if (clear & TIOCM_RTS)
1770                 info->MCR &= ~UART_MCR_RTS;
1771         if (clear & TIOCM_DTR)
1772                 info->MCR &= ~UART_MCR_DTR;
1773
1774         serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1775         serial_out(info, UART_ESI_CMD2, UART_MCR);
1776         serial_out(info, UART_ESI_CMD2, info->MCR);
1777
1778         spin_unlock_irqrestore(&info->lock, flags);
1779         return 0;
1780 }
1781
1782 /*
1783  * rs_break() --- routine which turns the break handling on or off
1784  */
1785 static void esp_break(struct tty_struct *tty, int break_state)
1786 {
1787         struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1788         unsigned long flags;
1789         
1790         if (serial_paranoia_check(info, tty->name, "esp_break"))
1791                 return;
1792
1793         if (break_state == -1) {
1794                 spin_lock_irqsave(&info->lock, flags);
1795                 serial_out(info, UART_ESI_CMD1, ESI_ISSUE_BREAK);
1796                 serial_out(info, UART_ESI_CMD2, 0x01);
1797                 spin_unlock_irqrestore(&info->lock, flags);
1798
1799                 /* FIXME - new style wait needed here */
1800                 interruptible_sleep_on(&info->break_wait);
1801         } else {
1802                 spin_lock_irqsave(&info->lock, flags);
1803                 serial_out(info, UART_ESI_CMD1, ESI_ISSUE_BREAK);
1804                 serial_out(info, UART_ESI_CMD2, 0x00);
1805                 spin_unlock_irqrestore(&info->lock, flags);
1806         }
1807 }
1808
1809 static int rs_ioctl(struct tty_struct *tty, struct file * file,
1810                     unsigned int cmd, unsigned long arg)
1811 {
1812         struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1813         struct async_icount cprev, cnow;        /* kernel counter temps */
1814         struct serial_icounter_struct __user *p_cuser;  /* user space */
1815         void __user *argp = (void __user *)arg;
1816         unsigned long flags;
1817
1818         if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1819                 return -ENODEV;
1820
1821         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1822             (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD)  &&
1823             (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT) &&
1824             (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT) &&
1825             (cmd != TIOCGHAYESESP) && (cmd != TIOCSHAYESESP)) {
1826                 if (tty->flags & (1 << TTY_IO_ERROR))
1827                     return -EIO;
1828         }
1829         
1830         switch (cmd) {
1831                 case TIOCGSERIAL:
1832                         return get_serial_info(info, argp);
1833                 case TIOCSSERIAL:
1834                         return set_serial_info(info, argp);
1835                 case TIOCSERCONFIG:
1836                         /* do not reconfigure after initial configuration */
1837                         return 0;
1838
1839                 case TIOCSERGWILD:
1840                         return put_user(0L, (unsigned long __user *)argp);
1841
1842                 case TIOCSERGETLSR: /* Get line status register */
1843                             return get_lsr_info(info, argp);
1844
1845                 case TIOCSERSWILD:
1846                         if (!capable(CAP_SYS_ADMIN))
1847                                 return -EPERM;
1848                         return 0;
1849
1850                 /*
1851                  * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1852                  * - mask passed in arg for lines of interest
1853                  *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1854                  * Caller should use TIOCGICOUNT to see which one it was
1855                  */
1856                  case TIOCMIWAIT:
1857                         spin_lock_irqsave(&info->lock, flags);
1858                         cprev = info->icount;   /* note the counters on entry */
1859                         spin_unlock_irqrestore(&info->lock, flags);
1860                         while (1) {
1861                                 /* FIXME: convert to new style wakeup */
1862                                 interruptible_sleep_on(&info->delta_msr_wait);
1863                                 /* see if a signal did it */
1864                                 if (signal_pending(current))
1865                                         return -ERESTARTSYS;
1866                                 spin_lock_irqsave(&info->lock, flags);
1867                                 cnow = info->icount;    /* atomic copy */
1868                                 spin_unlock_irqrestore(&info->lock, flags);
1869                                 if (cnow.rng == cprev.rng &&
1870                                     cnow.dsr == cprev.dsr && 
1871                                     cnow.dcd == cprev.dcd &&
1872                                     cnow.cts == cprev.cts)
1873                                         return -EIO; /* no change => error */
1874                                 if (((arg & TIOCM_RNG) &&
1875                                      (cnow.rng != cprev.rng)) ||
1876                                      ((arg & TIOCM_DSR) &&
1877                                       (cnow.dsr != cprev.dsr)) ||
1878                                      ((arg & TIOCM_CD) &&
1879                                       (cnow.dcd != cprev.dcd)) ||
1880                                      ((arg & TIOCM_CTS) &&
1881                                       (cnow.cts != cprev.cts)) ) {
1882                                         return 0;
1883                                 }
1884                                 cprev = cnow;
1885                         }
1886                         /* NOTREACHED */
1887
1888                 /* 
1889                  * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1890                  * Return: write counters to the user passed counter struct
1891                  * NB: both 1->0 and 0->1 transitions are counted except for
1892                  *     RI where only 0->1 is counted.
1893                  */
1894                 case TIOCGICOUNT:
1895                         spin_lock_irqsave(&info->lock, flags);
1896                         cnow = info->icount;
1897                         spin_unlock_irqrestore(&info->lock, flags);
1898                         p_cuser = argp;
1899                         if (put_user(cnow.cts, &p_cuser->cts) ||
1900                             put_user(cnow.dsr, &p_cuser->dsr) ||
1901                             put_user(cnow.rng, &p_cuser->rng) ||
1902                             put_user(cnow.dcd, &p_cuser->dcd))
1903                                 return -EFAULT;
1904
1905                         return 0;
1906         case TIOCGHAYESESP:
1907                 return get_esp_config(info, argp);
1908         case TIOCSHAYESESP:
1909                 return set_esp_config(info, argp);
1910
1911                 default:
1912                         return -ENOIOCTLCMD;
1913                 }
1914         return 0;
1915 }
1916
1917 static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
1918 {
1919         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1920         unsigned long flags;
1921
1922         if (   (tty->termios->c_cflag == old_termios->c_cflag)
1923             && (   RELEVANT_IFLAG(tty->termios->c_iflag) 
1924                 == RELEVANT_IFLAG(old_termios->c_iflag)))
1925                 return;
1926
1927         change_speed(info);
1928
1929         spin_lock_irqsave(&info->lock, flags);
1930
1931         /* Handle transition to B0 status */
1932         if ((old_termios->c_cflag & CBAUD) &&
1933                 !(tty->termios->c_cflag & CBAUD)) {
1934                 info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
1935                 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1936                 serial_out(info, UART_ESI_CMD2, UART_MCR);
1937                 serial_out(info, UART_ESI_CMD2, info->MCR);
1938         }
1939
1940         /* Handle transition away from B0 status */
1941         if (!(old_termios->c_cflag & CBAUD) &&
1942                 (tty->termios->c_cflag & CBAUD)) {
1943                 info->MCR |= (UART_MCR_DTR | UART_MCR_RTS);
1944                 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1945                 serial_out(info, UART_ESI_CMD2, UART_MCR);
1946                 serial_out(info, UART_ESI_CMD2, info->MCR);
1947         }
1948
1949         spin_unlock_irqrestore(&info->lock, flags);
1950
1951         /* Handle turning of CRTSCTS */
1952         if ((old_termios->c_cflag & CRTSCTS) &&
1953             !(tty->termios->c_cflag & CRTSCTS)) {
1954                 rs_start(tty);
1955         }
1956 }
1957
1958 /*
1959  * ------------------------------------------------------------
1960  * rs_close()
1961  * 
1962  * This routine is called when the serial port gets closed.  First, we
1963  * wait for the last remaining data to be sent.  Then, we unlink its
1964  * async structure from the interrupt chain if necessary, and we free
1965  * that IRQ if nothing is left in the chain.
1966  * ------------------------------------------------------------
1967  */
1968 static void rs_close(struct tty_struct *tty, struct file * filp)
1969 {
1970         struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1971         unsigned long flags;
1972
1973         if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
1974                 return;
1975         
1976         spin_lock_irqsave(&info->lock, flags);
1977         
1978         if (tty_hung_up_p(filp)) {
1979                 DBG_CNT("before DEC-hung");
1980                 goto out;
1981         }
1982         
1983 #ifdef SERIAL_DEBUG_OPEN
1984         printk("rs_close ttys%d, count = %d\n", info->line, info->count);
1985 #endif
1986         if ((tty->count == 1) && (info->count != 1)) {
1987                 /*
1988                  * Uh, oh.  tty->count is 1, which means that the tty
1989                  * structure will be freed.  Info->count should always
1990                  * be one in these conditions.  If it's greater than
1991                  * one, we've got real problems, since it means the
1992                  * serial port won't be shutdown.
1993                  */
1994                 printk("rs_close: bad serial port count; tty->count is 1, "
1995                        "info->count is %d\n", info->count);
1996                 info->count = 1;
1997         }
1998         if (--info->count < 0) {
1999                 printk("rs_close: bad serial port count for ttys%d: %d\n",
2000                        info->line, info->count);
2001                 info->count = 0;
2002         }
2003         if (info->count) {
2004                 DBG_CNT("before DEC-2");
2005                 goto out;
2006         }
2007         info->flags |= ASYNC_CLOSING;
2008
2009         spin_unlock_irqrestore(&info->lock, flags);
2010         /*
2011          * Now we wait for the transmit buffer to clear; and we notify 
2012          * the line discipline to only process XON/XOFF characters.
2013          */
2014         tty->closing = 1;
2015         if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
2016                 tty_wait_until_sent(tty, info->closing_wait);
2017         /*
2018          * At this point we stop accepting input.  To do this, we
2019          * disable the receive line status interrupts, and tell the
2020          * interrupt driver to stop checking the data ready bit in the
2021          * line status register.
2022          */
2023         /* info->IER &= ~UART_IER_RLSI; */
2024         info->IER &= ~UART_IER_RDI;
2025         info->read_status_mask &= ~UART_LSR_DR;
2026         if (info->flags & ASYNC_INITIALIZED) {
2027
2028                 spin_lock_irqsave(&info->lock, flags);
2029                 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
2030                 serial_out(info, UART_ESI_CMD2, info->IER);
2031
2032                 /* disable receive timeout */
2033                 serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
2034                 serial_out(info, UART_ESI_CMD2, 0x00);
2035
2036                 spin_unlock_irqrestore(&info->lock, flags);
2037
2038                 /*
2039                  * Before we drop DTR, make sure the UART transmitter
2040                  * has completely drained; this is especially
2041                  * important if there is a transmit FIFO!
2042                  */
2043                 rs_wait_until_sent(tty, info->timeout);
2044         }
2045         shutdown(info);
2046         if (tty->driver->flush_buffer)
2047                 tty->driver->flush_buffer(tty);
2048         tty_ldisc_flush(tty);
2049         tty->closing = 0;
2050         info->event = 0;
2051         info->tty = NULL;
2052
2053         if (info->blocked_open) {
2054                 if (info->close_delay) {
2055                         msleep_interruptible(jiffies_to_msecs(info->close_delay));
2056                 }
2057                 wake_up_interruptible(&info->open_wait);
2058         }
2059         info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
2060         wake_up_interruptible(&info->close_wait);
2061         return;
2062
2063 out:
2064         spin_unlock_irqrestore(&info->lock, flags);
2065 }
2066
2067 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
2068 {
2069         struct esp_struct *info = (struct esp_struct *)tty->driver_data;
2070         unsigned long orig_jiffies, char_time;
2071         unsigned long flags;
2072
2073         if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
2074                 return;
2075
2076         orig_jiffies = jiffies;
2077         char_time = ((info->timeout - HZ / 50) / 1024) / 5;
2078
2079         if (!char_time)
2080                 char_time = 1;
2081
2082         spin_lock_irqsave(&info->lock, flags);
2083         serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
2084         serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
2085
2086         while ((serial_in(info, UART_ESI_STAT1) != 0x03) ||
2087                 (serial_in(info, UART_ESI_STAT2) != 0xff)) {
2088
2089                 spin_unlock_irqrestore(&info->lock, flags);
2090                 msleep_interruptible(jiffies_to_msecs(char_time));
2091
2092                 if (signal_pending(current))
2093                         break;
2094
2095                 if (timeout && time_after(jiffies, orig_jiffies + timeout))
2096                         break;
2097
2098                 spin_lock_irqsave(&info->lock, flags);
2099                 serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
2100                 serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
2101         }
2102         spin_unlock_irqrestore(&info->lock, flags);
2103         set_current_state(TASK_RUNNING);
2104 }
2105
2106 /*
2107  * esp_hangup() --- called by tty_hangup() when a hangup is signaled.
2108  */
2109 static void esp_hangup(struct tty_struct *tty)
2110 {
2111         struct esp_struct * info = (struct esp_struct *)tty->driver_data;
2112         
2113         if (serial_paranoia_check(info, tty->name, "esp_hangup"))
2114                 return;
2115         
2116         rs_flush_buffer(tty);
2117         shutdown(info);
2118         info->event = 0;
2119         info->count = 0;
2120         info->flags &= ~ASYNC_NORMAL_ACTIVE;
2121         info->tty = NULL;
2122         wake_up_interruptible(&info->open_wait);
2123 }
2124
2125 /*
2126  * ------------------------------------------------------------
2127  * esp_open() and friends
2128  * ------------------------------------------------------------
2129  */
2130 static int block_til_ready(struct tty_struct *tty, struct file * filp,
2131                            struct esp_struct *info)
2132 {
2133         DECLARE_WAITQUEUE(wait, current);
2134         int             retval;
2135         int             do_clocal = 0;
2136         unsigned long   flags;
2137
2138         /*
2139          * If the device is in the middle of being closed, then block
2140          * until it's done, and then try again.
2141          */
2142         if (tty_hung_up_p(filp) ||
2143             (info->flags & ASYNC_CLOSING)) {
2144                 if (info->flags & ASYNC_CLOSING)
2145                         interruptible_sleep_on(&info->close_wait);
2146 #ifdef SERIAL_DO_RESTART
2147                 if (info->flags & ASYNC_HUP_NOTIFY)
2148                         return -EAGAIN;
2149                 else
2150                         return -ERESTARTSYS;
2151 #else
2152                 return -EAGAIN;
2153 #endif
2154         }
2155
2156         /*
2157          * If non-blocking mode is set, or the port is not enabled,
2158          * then make the check up front and then exit.
2159          */
2160         if ((filp->f_flags & O_NONBLOCK) ||
2161             (tty->flags & (1 << TTY_IO_ERROR))) {
2162                 info->flags |= ASYNC_NORMAL_ACTIVE;
2163                 return 0;
2164         }
2165
2166         if (tty->termios->c_cflag & CLOCAL)
2167                 do_clocal = 1;
2168
2169         /*
2170          * Block waiting for the carrier detect and the line to become
2171          * free (i.e., not in use by the callout).  While we are in
2172          * this loop, info->count is dropped by one, so that
2173          * rs_close() knows when to free things.  We restore it upon
2174          * exit, either normal or abnormal.
2175          */
2176         retval = 0;
2177         add_wait_queue(&info->open_wait, &wait);
2178 #ifdef SERIAL_DEBUG_OPEN
2179         printk("block_til_ready before block: ttys%d, count = %d\n",
2180                info->line, info->count);
2181 #endif
2182         spin_lock_irqsave(&info->lock, flags);
2183         if (!tty_hung_up_p(filp)) 
2184                 info->count--;
2185         info->blocked_open++;
2186         while (1) {
2187                 if ((tty->termios->c_cflag & CBAUD)) {
2188                         unsigned int scratch;
2189
2190                         serial_out(info, UART_ESI_CMD1, ESI_READ_UART);
2191                         serial_out(info, UART_ESI_CMD2, UART_MCR);
2192                         scratch = serial_in(info, UART_ESI_STAT1);
2193                         serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
2194                         serial_out(info, UART_ESI_CMD2, UART_MCR);
2195                         serial_out(info, UART_ESI_CMD2,
2196                                 scratch | UART_MCR_DTR | UART_MCR_RTS);
2197                 }
2198                 set_current_state(TASK_INTERRUPTIBLE);
2199                 if (tty_hung_up_p(filp) ||
2200                     !(info->flags & ASYNC_INITIALIZED)) {
2201 #ifdef SERIAL_DO_RESTART
2202                         if (info->flags & ASYNC_HUP_NOTIFY)
2203                                 retval = -EAGAIN;
2204                         else
2205                                 retval = -ERESTARTSYS;  
2206 #else
2207                         retval = -EAGAIN;
2208 #endif
2209                         break;
2210                 }
2211
2212                 serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
2213                 if (serial_in(info, UART_ESI_STAT2) & UART_MSR_DCD)
2214                         do_clocal = 1;
2215
2216                 if (!(info->flags & ASYNC_CLOSING) &&
2217                     (do_clocal))
2218                         break;
2219                 if (signal_pending(current)) {
2220                         retval = -ERESTARTSYS;
2221                         break;
2222                 }
2223 #ifdef SERIAL_DEBUG_OPEN
2224                 printk("block_til_ready blocking: ttys%d, count = %d\n",
2225                        info->line, info->count);
2226 #endif
2227                 spin_unlock_irqrestore(&info->lock, flags);
2228                 schedule();
2229                 spin_lock_irqsave(&info->lock, flags);
2230         }
2231         set_current_state(TASK_RUNNING);
2232         remove_wait_queue(&info->open_wait, &wait);
2233         if (!tty_hung_up_p(filp))
2234                 info->count++;
2235         info->blocked_open--;
2236         spin_unlock_irqrestore(&info->lock, flags);
2237 #ifdef SERIAL_DEBUG_OPEN
2238         printk("block_til_ready after blocking: ttys%d, count = %d\n",
2239                info->line, info->count);
2240 #endif
2241         if (retval)
2242                 return retval;
2243         info->flags |= ASYNC_NORMAL_ACTIVE;
2244         return 0;
2245 }       
2246
2247 /*
2248  * This routine is called whenever a serial port is opened.  It
2249  * enables interrupts for a serial port, linking in its async structure into
2250  * the IRQ chain.   It also performs the serial-specific
2251  * initialization for the tty structure.
2252  */
2253 static int esp_open(struct tty_struct *tty, struct file * filp)
2254 {
2255         struct esp_struct       *info;
2256         int                     retval, line;
2257         unsigned long           flags;
2258
2259         line = tty->index;
2260         if ((line < 0) || (line >= NR_PORTS))
2261                 return -ENODEV;
2262
2263         /* find the port in the chain */
2264
2265         info = ports;
2266
2267         while (info && (info->line != line))
2268                 info = info->next_port;
2269
2270         if (!info) {
2271                 serial_paranoia_check(info, tty->name, "esp_open");
2272                 return -ENODEV;
2273         }
2274
2275 #ifdef SERIAL_DEBUG_OPEN
2276         printk("esp_open %s, count = %d\n", tty->name, info->count);
2277 #endif
2278         spin_lock_irqsave(&info->lock, flags);
2279         info->count++;
2280         tty->driver_data = info;
2281         info->tty = tty;
2282
2283         spin_unlock_irqrestore(&info->lock, flags);
2284         
2285         /*
2286          * Start up serial port
2287          */
2288         retval = startup(info);
2289         if (retval)
2290                 return retval;
2291
2292         retval = block_til_ready(tty, filp, info);
2293         if (retval) {
2294 #ifdef SERIAL_DEBUG_OPEN
2295                 printk("esp_open returning after block_til_ready with %d\n",
2296                        retval);
2297 #endif
2298                 return retval;
2299         }
2300
2301 #ifdef SERIAL_DEBUG_OPEN
2302         printk("esp_open %s successful...", tty->name);
2303 #endif
2304         return 0;
2305 }
2306
2307 /*
2308  * ---------------------------------------------------------------------
2309  * espserial_init() and friends
2310  *
2311  * espserial_init() is called at boot-time to initialize the serial driver.
2312  * ---------------------------------------------------------------------
2313  */
2314
2315 /*
2316  * This routine prints out the appropriate serial driver version
2317  * number, and identifies which options were configured into this
2318  * driver.
2319  */
2320  
2321 static inline void show_serial_version(void)
2322 {
2323         printk(KERN_INFO "%s version %s (DMA %u)\n",
2324                 serial_name, serial_version, dma);
2325 }
2326
2327 /*
2328  * This routine is called by espserial_init() to initialize a specific serial
2329  * port.
2330  */
2331 static inline int autoconfig(struct esp_struct * info)
2332 {
2333         int port_detected = 0;
2334         unsigned long flags;
2335
2336         if (!request_region(info->port, REGION_SIZE, "esp serial"))
2337                 return -EIO;
2338
2339         spin_lock_irqsave(&info->lock, flags);
2340         /*
2341          * Check for ESP card
2342          */
2343
2344         if (serial_in(info, UART_ESI_BASE) == 0xf3) {
2345                 serial_out(info, UART_ESI_CMD1, 0x00);
2346                 serial_out(info, UART_ESI_CMD1, 0x01);
2347
2348                 if ((serial_in(info, UART_ESI_STAT2) & 0x70) == 0x20) {
2349                         port_detected = 1;
2350
2351                         if (!(info->irq)) {
2352                                 serial_out(info, UART_ESI_CMD1, 0x02);
2353
2354                                 if (serial_in(info, UART_ESI_STAT1) & 0x01)
2355                                         info->irq = 3;
2356                                 else
2357                                         info->irq = 4;
2358                         }
2359
2360
2361                         /* put card in enhanced mode */
2362                         /* this prevents access through */
2363                         /* the "old" IO ports */
2364                         esp_basic_init(info);
2365
2366                         /* clear out MCR */
2367                         serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
2368                         serial_out(info, UART_ESI_CMD2, UART_MCR);
2369                         serial_out(info, UART_ESI_CMD2, 0x00);
2370                 }
2371         }
2372         if (!port_detected)
2373                 release_region(info->port, REGION_SIZE);
2374
2375         spin_unlock_irqrestore(&info->lock, flags);
2376         return (port_detected);
2377 }
2378
2379 static struct tty_operations esp_ops = {
2380         .open = esp_open,
2381         .close = rs_close,
2382         .write = rs_write,
2383         .put_char = rs_put_char,
2384         .flush_chars = rs_flush_chars,
2385         .write_room = rs_write_room,
2386         .chars_in_buffer = rs_chars_in_buffer,
2387         .flush_buffer = rs_flush_buffer,
2388         .ioctl = rs_ioctl,
2389         .throttle = rs_throttle,
2390         .unthrottle = rs_unthrottle,
2391         .set_termios = rs_set_termios,
2392         .stop = rs_stop,
2393         .start = rs_start,
2394         .hangup = esp_hangup,
2395         .break_ctl = esp_break,
2396         .wait_until_sent = rs_wait_until_sent,
2397         .tiocmget = esp_tiocmget,
2398         .tiocmset = esp_tiocmset,
2399 };
2400
2401 /*
2402  * The serial driver boot-time initialization code!
2403  */
2404 static int __init espserial_init(void)
2405 {
2406         int i, offset;
2407         struct esp_struct * info;
2408         struct esp_struct *last_primary = NULL;
2409         int esp[] = {0x100,0x140,0x180,0x200,0x240,0x280,0x300,0x380};
2410
2411         esp_driver = alloc_tty_driver(NR_PORTS);
2412         if (!esp_driver)
2413                 return -ENOMEM;
2414         
2415         for (i = 0; i < NR_PRIMARY; i++) {
2416                 if (irq[i] != 0) {
2417                         if ((irq[i] < 2) || (irq[i] > 15) || (irq[i] == 6) ||
2418                             (irq[i] == 8) || (irq[i] == 13))
2419                                 irq[i] = 0;
2420                         else if (irq[i] == 2)
2421                                 irq[i] = 9;
2422                 }
2423         }
2424
2425         if ((dma != 1) && (dma != 3))
2426                 dma = 0;
2427
2428         if ((rx_trigger < 1) || (rx_trigger > 1023))
2429                 rx_trigger = 768;
2430
2431         if ((tx_trigger < 1) || (tx_trigger > 1023))
2432                 tx_trigger = 768;
2433
2434         if ((flow_off < 1) || (flow_off > 1023))
2435                 flow_off = 1016;
2436         
2437         if ((flow_on < 1) || (flow_on > 1023))
2438                 flow_on = 944;
2439
2440         if ((rx_timeout < 0) || (rx_timeout > 255))
2441                 rx_timeout = 128;
2442         
2443         if (flow_on >= flow_off)
2444                 flow_on = flow_off - 1;
2445
2446         show_serial_version();
2447
2448         /* Initialize the tty_driver structure */
2449         
2450         esp_driver->owner = THIS_MODULE;
2451         esp_driver->name = "ttyP";
2452         esp_driver->devfs_name = "tts/P";
2453         esp_driver->major = ESP_IN_MAJOR;
2454         esp_driver->minor_start = 0;
2455         esp_driver->type = TTY_DRIVER_TYPE_SERIAL;
2456         esp_driver->subtype = SERIAL_TYPE_NORMAL;
2457         esp_driver->init_termios = tty_std_termios;
2458         esp_driver->init_termios.c_cflag =
2459                 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
2460         esp_driver->flags = TTY_DRIVER_REAL_RAW;
2461         tty_set_operations(esp_driver, &esp_ops);
2462         if (tty_register_driver(esp_driver))
2463         {
2464                 printk(KERN_ERR "Couldn't register esp serial driver");
2465                 put_tty_driver(esp_driver);
2466                 return 1;
2467         }
2468
2469         info = kmalloc(sizeof(struct esp_struct), GFP_KERNEL);
2470
2471         if (!info)
2472         {
2473                 printk(KERN_ERR "Couldn't allocate memory for esp serial device information\n");
2474                 tty_unregister_driver(esp_driver);
2475                 put_tty_driver(esp_driver);
2476                 return 1;
2477         }
2478
2479         memset((void *)info, 0, sizeof(struct esp_struct));
2480         spin_lock_init(&info->lock);
2481         /* rx_trigger, tx_trigger are needed by autoconfig */
2482         info->config.rx_trigger = rx_trigger;
2483         info->config.tx_trigger = tx_trigger;
2484
2485         i = 0;
2486         offset = 0;
2487
2488         do {
2489                 info->port = esp[i] + offset;
2490                 info->irq = irq[i];
2491                 info->line = (i * 8) + (offset / 8);
2492
2493                 if (!autoconfig(info)) {
2494                         i++;
2495                         offset = 0;
2496                         continue;
2497                 }
2498
2499                 info->custom_divisor = (divisor[i] >> (offset / 2)) & 0xf;
2500                 info->flags = STD_COM_FLAGS;
2501                 if (info->custom_divisor)
2502                         info->flags |= ASYNC_SPD_CUST;
2503                 info->magic = ESP_MAGIC;
2504                 info->close_delay = 5*HZ/10;
2505                 info->closing_wait = 30*HZ;
2506                 INIT_WORK(&info->tqueue, do_softint, info);
2507                 INIT_WORK(&info->tqueue_hangup, do_serial_hangup, info);
2508                 info->config.rx_timeout = rx_timeout;
2509                 info->config.flow_on = flow_on;
2510                 info->config.flow_off = flow_off;
2511                 info->config.pio_threshold = pio_threshold;
2512                 info->next_port = ports;
2513                 init_waitqueue_head(&info->open_wait);
2514                 init_waitqueue_head(&info->close_wait);
2515                 init_waitqueue_head(&info->delta_msr_wait);
2516                 init_waitqueue_head(&info->break_wait);
2517                 ports = info;
2518                 printk(KERN_INFO "ttyP%d at 0x%04x (irq = %d) is an ESP ",
2519                         info->line, info->port, info->irq);
2520
2521                 if (info->line % 8) {
2522                         printk("secondary port\n");
2523                         /* 8 port cards can't do DMA */
2524                         info->stat_flags |= ESP_STAT_NEVER_DMA;
2525
2526                         if (last_primary)
2527                                 last_primary->stat_flags |= ESP_STAT_NEVER_DMA;
2528                 } else {
2529                         printk("primary port\n");
2530                         last_primary = info;
2531                         irq[i] = info->irq;
2532                 }
2533
2534                 if (!dma)
2535                         info->stat_flags |= ESP_STAT_NEVER_DMA;
2536
2537                 info = kmalloc(sizeof(struct esp_struct), GFP_KERNEL);
2538                 if (!info)
2539                 {
2540                         printk(KERN_ERR "Couldn't allocate memory for esp serial device information\n"); 
2541
2542                         /* allow use of the already detected ports */
2543                         return 0;
2544                 }
2545
2546                 memset((void *)info, 0, sizeof(struct esp_struct));
2547                 /* rx_trigger, tx_trigger are needed by autoconfig */
2548                 info->config.rx_trigger = rx_trigger;
2549                 info->config.tx_trigger = tx_trigger;
2550
2551                 if (offset == 56) {
2552                         i++;
2553                         offset = 0;
2554                 } else {
2555                         offset += 8;
2556                 }
2557         } while (i < NR_PRIMARY);
2558
2559         /* free the last port memory allocation */
2560         kfree(info);
2561
2562         return 0;
2563 }
2564
2565 static void __exit espserial_exit(void) 
2566 {
2567         int e1;
2568         struct esp_struct *temp_async;
2569         struct esp_pio_buffer *pio_buf;
2570
2571         /* printk("Unloading %s: version %s\n", serial_name, serial_version); */
2572         if ((e1 = tty_unregister_driver(esp_driver)))
2573                 printk("SERIAL: failed to unregister serial driver (%d)\n",
2574                        e1);
2575         put_tty_driver(esp_driver);
2576
2577         while (ports) {
2578                 if (ports->port) {
2579                         release_region(ports->port, REGION_SIZE);
2580                 }
2581                 temp_async = ports->next_port;
2582                 kfree(ports);
2583                 ports = temp_async;
2584         }
2585
2586         if (dma_buffer)
2587                 free_pages((unsigned long)dma_buffer,
2588                         get_order(DMA_BUFFER_SZ));
2589
2590         while (free_pio_buf) {
2591                 pio_buf = free_pio_buf->next;
2592                 kfree(free_pio_buf);
2593                 free_pio_buf = pio_buf;
2594         }
2595 }
2596
2597 module_init(espserial_init);
2598 module_exit(espserial_exit);