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[PATCH] m68k/MVME167: SERIAL167 tty flip buffer updates
[linux-2.6/kvm.git] / drivers / char / esp.c
blob15a4ea896328cc23ad6be070357b76baf41c59bd
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 {
620 struct esp_struct * info;
621 unsigned err_status;
622 unsigned int scratch;
623
624 #ifdef SERIAL_DEBUG_INTR
625 printk("rs_interrupt_single(%d)...", irq);
626 #endif
627 info = (struct esp_struct *)dev_id;
628 err_status = 0;
629 scratch = serial_in(info, UART_ESI_SID);
630
631 spin_lock(&info->lock);
632
633 if (!info->tty) {
634 spin_unlock(&info->lock);
635 return IRQ_NONE;
636 }
637
638 if (scratch & 0x04) { /* error */
639 serial_out(info, UART_ESI_CMD1, ESI_GET_ERR_STAT);
640 err_status = serial_in(info, UART_ESI_STAT1);
641 serial_in(info, UART_ESI_STAT2);
642
643 if (err_status & 0x01)
644 info->stat_flags |= ESP_STAT_RX_TIMEOUT;
645
646 if (err_status & 0x20) /* UART status */
647 check_modem_status(info);
648
649 if (err_status & 0x80) /* Start break */
650 wake_up_interruptible(&info->break_wait);
651 }
652
653 if ((scratch & 0x88) || /* DMA completed or timed out */
654 (err_status & 0x1c) /* receive error */) {
655 if (info->stat_flags & ESP_STAT_DMA_RX)
656 receive_chars_dma_done(info, err_status);
657 else if (info->stat_flags & ESP_STAT_DMA_TX)
658 transmit_chars_dma_done(info);
659 }
660
661 if (!(info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) &&
662 ((scratch & 0x01) || (info->stat_flags & ESP_STAT_RX_TIMEOUT)) &&
663 (info->IER & UART_IER_RDI)) {
664 int num_bytes;
665
666 serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
667 serial_out(info, UART_ESI_CMD1, ESI_GET_RX_AVAIL);
668 num_bytes = serial_in(info, UART_ESI_STAT1) << 8;
669 num_bytes |= serial_in(info, UART_ESI_STAT2);
670
671 num_bytes = tty_buffer_request_room(info->tty, num_bytes);
672
673 if (num_bytes) {
674 if (dma_bytes ||
675 (info->stat_flags & ESP_STAT_USE_PIO) ||
676 (num_bytes <= info->config.pio_threshold))
677 receive_chars_pio(info, num_bytes);
678 else
679 receive_chars_dma(info, num_bytes);
680 }
681 }
682
683 if (!(info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) &&
684 (scratch & 0x02) && (info->IER & UART_IER_THRI)) {
685 if ((info->xmit_cnt <= 0) || info->tty->stopped) {
686 info->IER &= ~UART_IER_THRI;
687 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
688 serial_out(info, UART_ESI_CMD2, info->IER);
689 } else {
690 int num_bytes;
691
692 serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
693 serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
694 num_bytes = serial_in(info, UART_ESI_STAT1) << 8;
695 num_bytes |= serial_in(info, UART_ESI_STAT2);
696
697 if (num_bytes > info->xmit_cnt)
698 num_bytes = info->xmit_cnt;
699
700 if (num_bytes) {
701 if (dma_bytes ||
702 (info->stat_flags & ESP_STAT_USE_PIO) ||
703 (num_bytes <= info->config.pio_threshold))
704 transmit_chars_pio(info, num_bytes);
705 else
706 transmit_chars_dma(info, num_bytes);
707 }
708 }
709 }
710
711 info->last_active = jiffies;
712
713 #ifdef SERIAL_DEBUG_INTR
714 printk("end.\n");
715 #endif
716 spin_unlock(&info->lock);
717 return IRQ_HANDLED;
718 }
719
720 /*
721 * -------------------------------------------------------------------
722 * Here ends the serial interrupt routines.
723 * -------------------------------------------------------------------
724 */
725
726 static void do_softint(void *private_)
727 {
728 struct esp_struct *info = (struct esp_struct *) private_;
729 struct tty_struct *tty;
730
731 tty = info->tty;
732 if (!tty)
733 return;
734
735 if (test_and_clear_bit(ESP_EVENT_WRITE_WAKEUP, &info->event)) {
736 tty_wakeup(tty);
737 }
738 }
739
740 /*
741 * This routine is called from the scheduler tqueue when the interrupt
742 * routine has signalled that a hangup has occurred. The path of
743 * hangup processing is:
744 *
745 * serial interrupt routine -> (scheduler tqueue) ->
746 * do_serial_hangup() -> tty->hangup() -> esp_hangup()
747 *
748 */
749 static void do_serial_hangup(void *private_)
750 {
751 struct esp_struct *info = (struct esp_struct *) private_;
752 struct tty_struct *tty;
753
754 tty = info->tty;
755 if (tty)
756 tty_hangup(tty);
757 }
758
759 /*
760 * ---------------------------------------------------------------
761 * Low level utility subroutines for the serial driver: routines to
762 * figure out the appropriate timeout for an interrupt chain, routines
763 * to initialize and startup a serial port, and routines to shutdown a
764 * serial port. Useful stuff like that.
765 *
766 * Caller should hold lock
767 * ---------------------------------------------------------------
768 */
769
770 static inline void esp_basic_init(struct esp_struct * info)
771 {
772 /* put ESPC in enhanced mode */
773 serial_out(info, UART_ESI_CMD1, ESI_SET_MODE);
774
775 if (info->stat_flags & ESP_STAT_NEVER_DMA)
776 serial_out(info, UART_ESI_CMD2, 0x01);
777 else
778 serial_out(info, UART_ESI_CMD2, 0x31);
779
780 /* disable interrupts for now */
781 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
782 serial_out(info, UART_ESI_CMD2, 0x00);
783
784 /* set interrupt and DMA channel */
785 serial_out(info, UART_ESI_CMD1, ESI_SET_IRQ);
786
787 if (info->stat_flags & ESP_STAT_NEVER_DMA)
788 serial_out(info, UART_ESI_CMD2, 0x01);
789 else
790 serial_out(info, UART_ESI_CMD2, (dma << 4) | 0x01);
791
792 serial_out(info, UART_ESI_CMD1, ESI_SET_ENH_IRQ);
793
794 if (info->line % 8) /* secondary port */
795 serial_out(info, UART_ESI_CMD2, 0x0d); /* shared */
796 else if (info->irq == 9)
797 serial_out(info, UART_ESI_CMD2, 0x02);
798 else
799 serial_out(info, UART_ESI_CMD2, info->irq);
800
801 /* set error status mask (check this) */
802 serial_out(info, UART_ESI_CMD1, ESI_SET_ERR_MASK);
803
804 if (info->stat_flags & ESP_STAT_NEVER_DMA)
805 serial_out(info, UART_ESI_CMD2, 0xa1);
806 else
807 serial_out(info, UART_ESI_CMD2, 0xbd);
808
809 serial_out(info, UART_ESI_CMD2, 0x00);
810
811 /* set DMA timeout */
812 serial_out(info, UART_ESI_CMD1, ESI_SET_DMA_TMOUT);
813 serial_out(info, UART_ESI_CMD2, 0xff);
814
815 /* set FIFO trigger levels */
816 serial_out(info, UART_ESI_CMD1, ESI_SET_TRIGGER);
817 serial_out(info, UART_ESI_CMD2, info->config.rx_trigger >> 8);
818 serial_out(info, UART_ESI_CMD2, info->config.rx_trigger);
819 serial_out(info, UART_ESI_CMD2, info->config.tx_trigger >> 8);
820 serial_out(info, UART_ESI_CMD2, info->config.tx_trigger);
821
822 /* Set clock scaling and wait states */
823 serial_out(info, UART_ESI_CMD1, ESI_SET_PRESCALAR);
824 serial_out(info, UART_ESI_CMD2, 0x04 | ESPC_SCALE);
825
826 /* set reinterrupt pacing */
827 serial_out(info, UART_ESI_CMD1, ESI_SET_REINTR);
828 serial_out(info, UART_ESI_CMD2, 0xff);
829 }
830
831 static int startup(struct esp_struct * info)
832 {
833 unsigned long flags;
834 int retval=0;
835 unsigned int num_chars;
836
837 spin_lock_irqsave(&info->lock, flags);
838
839 if (info->flags & ASYNC_INITIALIZED)
840 goto out;
841
842 if (!info->xmit_buf) {
843 info->xmit_buf = (unsigned char *)get_zeroed_page(GFP_ATOMIC);
844 retval = -ENOMEM;
845 if (!info->xmit_buf)
846 goto out;
847 }
848
849 #ifdef SERIAL_DEBUG_OPEN
850 printk("starting up ttys%d (irq %d)...", info->line, info->irq);
851 #endif
852
853 /* Flush the RX buffer. Using the ESI flush command may cause */
854 /* wild interrupts, so read all the data instead. */
855
856 serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
857 serial_out(info, UART_ESI_CMD1, ESI_GET_RX_AVAIL);
858 num_chars = serial_in(info, UART_ESI_STAT1) << 8;
859 num_chars |= serial_in(info, UART_ESI_STAT2);
860
861 while (num_chars > 1) {
862 inw(info->port + UART_ESI_RX);
863 num_chars -= 2;
864 }
865
866 if (num_chars)
867 serial_in(info, UART_ESI_RX);
868
869 /* set receive character timeout */
870 serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
871 serial_out(info, UART_ESI_CMD2, info->config.rx_timeout);
872
873 /* clear all flags except the "never DMA" flag */
874 info->stat_flags &= ESP_STAT_NEVER_DMA;
875
876 if (info->stat_flags & ESP_STAT_NEVER_DMA)
877 info->stat_flags |= ESP_STAT_USE_PIO;
878
879 spin_unlock_irqrestore(&info->lock, flags);
880
881 /*
882 * Allocate the IRQ
883 */
884
885 retval = request_irq(info->irq, rs_interrupt_single, IRQF_SHARED,
886 "esp serial", info);
887
888 if (retval) {
889 if (capable(CAP_SYS_ADMIN)) {
890 if (info->tty)
891 set_bit(TTY_IO_ERROR,
892 &info->tty->flags);
893 retval = 0;
894 }
895 goto out_unlocked;
896 }
897
898 if (!(info->stat_flags & ESP_STAT_USE_PIO) && !dma_buffer) {
899 dma_buffer = (char *)__get_dma_pages(
900 GFP_KERNEL, get_order(DMA_BUFFER_SZ));
901
902 /* use PIO mode if DMA buf/chan cannot be allocated */
903 if (!dma_buffer)
904 info->stat_flags |= ESP_STAT_USE_PIO;
905 else if (request_dma(dma, "esp serial")) {
906 free_pages((unsigned long)dma_buffer,
907 get_order(DMA_BUFFER_SZ));
908 dma_buffer = NULL;
909 info->stat_flags |= ESP_STAT_USE_PIO;
910 }
911
912 }
913
914 info->MCR = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2;
915
916 spin_lock_irqsave(&info->lock, flags);
917 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
918 serial_out(info, UART_ESI_CMD2, UART_MCR);
919 serial_out(info, UART_ESI_CMD2, info->MCR);
920
921 /*
922 * Finally, enable interrupts
923 */
924 /* info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI; */
925 info->IER = UART_IER_RLSI | UART_IER_RDI | UART_IER_DMA_TMOUT |
926 UART_IER_DMA_TC;
927 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
928 serial_out(info, UART_ESI_CMD2, info->IER);
929
930 if (info->tty)
931 clear_bit(TTY_IO_ERROR, &info->tty->flags);
932 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
933 spin_unlock_irqrestore(&info->lock, flags);
934
935 /*
936 * Set up the tty->alt_speed kludge
937 */
938 if (info->tty) {
939 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
940 info->tty->alt_speed = 57600;
941 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
942 info->tty->alt_speed = 115200;
943 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
944 info->tty->alt_speed = 230400;
945 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
946 info->tty->alt_speed = 460800;
947 }
948
949 /*
950 * set the speed of the serial port
951 */
952 change_speed(info);
953 info->flags |= ASYNC_INITIALIZED;
954 return 0;
955
956 out:
957 spin_unlock_irqrestore(&info->lock, flags);
958 out_unlocked:
959 return retval;
960 }
961
962 /*
963 * This routine will shutdown a serial port; interrupts are disabled, and
964 * DTR is dropped if the hangup on close termio flag is on.
965 */
966 static void shutdown(struct esp_struct * info)
967 {
968 unsigned long flags, f;
969
970 if (!(info->flags & ASYNC_INITIALIZED))
971 return;
972
973 #ifdef SERIAL_DEBUG_OPEN
974 printk("Shutting down serial port %d (irq %d)....", info->line,
975 info->irq);
976 #endif
977
978 spin_lock_irqsave(&info->lock, flags);
979 /*
980 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
981 * here so the queue might never be waken up
982 */
983 wake_up_interruptible(&info->delta_msr_wait);
984 wake_up_interruptible(&info->break_wait);
985
986 /* stop a DMA transfer on the port being closed */
987 /* DMA lock is higher priority always */
988 if (info->stat_flags & (ESP_STAT_DMA_RX | ESP_STAT_DMA_TX)) {
989 f=claim_dma_lock();
990 disable_dma(dma);
991 clear_dma_ff(dma);
992 release_dma_lock(f);
993
994 dma_bytes = 0;
995 }
996
997 /*
998 * Free the IRQ
999 */
1000 free_irq(info->irq, info);
1001
1002 if (dma_buffer) {
1003 struct esp_struct *current_port = ports;
1004
1005 while (current_port) {
1006 if ((current_port != info) &&
1007 (current_port->flags & ASYNC_INITIALIZED))
1008 break;
1009
1010 current_port = current_port->next_port;
1011 }
1012
1013 if (!current_port) {
1014 free_dma(dma);
1015 free_pages((unsigned long)dma_buffer,
1016 get_order(DMA_BUFFER_SZ));
1017 dma_buffer = NULL;
1018 }
1019 }
1020
1021 if (info->xmit_buf) {
1022 free_page((unsigned long) info->xmit_buf);
1023 info->xmit_buf = NULL;
1024 }
1025
1026 info->IER = 0;
1027 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1028 serial_out(info, UART_ESI_CMD2, 0x00);
1029
1030 if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
1031 info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
1032
1033 info->MCR &= ~UART_MCR_OUT2;
1034 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1035 serial_out(info, UART_ESI_CMD2, UART_MCR);
1036 serial_out(info, UART_ESI_CMD2, info->MCR);
1037
1038 if (info->tty)
1039 set_bit(TTY_IO_ERROR, &info->tty->flags);
1040
1041 info->flags &= ~ASYNC_INITIALIZED;
1042 spin_unlock_irqrestore(&info->lock, flags);
1043 }
1044
1045 /*
1046 * This routine is called to set the UART divisor registers to match
1047 * the specified baud rate for a serial port.
1048 */
1049 static void change_speed(struct esp_struct *info)
1050 {
1051 unsigned short port;
1052 int quot = 0;
1053 unsigned cflag,cval;
1054 int baud, bits;
1055 unsigned char flow1 = 0, flow2 = 0;
1056 unsigned long flags;
1057
1058 if (!info->tty || !info->tty->termios)
1059 return;
1060 cflag = info->tty->termios->c_cflag;
1061 port = info->port;
1062
1063 /* byte size and parity */
1064 switch (cflag & CSIZE) {
1065 case CS5: cval = 0x00; bits = 7; break;
1066 case CS6: cval = 0x01; bits = 8; break;
1067 case CS7: cval = 0x02; bits = 9; break;
1068 case CS8: cval = 0x03; bits = 10; break;
1069 default: cval = 0x00; bits = 7; break;
1070 }
1071 if (cflag & CSTOPB) {
1072 cval |= 0x04;
1073 bits++;
1074 }
1075 if (cflag & PARENB) {
1076 cval |= UART_LCR_PARITY;
1077 bits++;
1078 }
1079 if (!(cflag & PARODD))
1080 cval |= UART_LCR_EPAR;
1081 #ifdef CMSPAR
1082 if (cflag & CMSPAR)
1083 cval |= UART_LCR_SPAR;
1084 #endif
1085
1086 baud = tty_get_baud_rate(info->tty);
1087 if (baud == 38400 &&
1088 ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
1089 quot = info->custom_divisor;
1090 else {
1091 if (baud == 134)
1092 /* Special case since 134 is really 134.5 */
1093 quot = (2*BASE_BAUD / 269);
1094 else if (baud)
1095 quot = BASE_BAUD / baud;
1096 }
1097 /* If the quotient is ever zero, default to 9600 bps */
1098 if (!quot)
1099 quot = BASE_BAUD / 9600;
1100
1101 info->timeout = ((1024 * HZ * bits * quot) / BASE_BAUD) + (HZ / 50);
1102
1103 /* CTS flow control flag and modem status interrupts */
1104 /* info->IER &= ~UART_IER_MSI; */
1105 if (cflag & CRTSCTS) {
1106 info->flags |= ASYNC_CTS_FLOW;
1107 /* info->IER |= UART_IER_MSI; */
1108 flow1 = 0x04;
1109 flow2 = 0x10;
1110 } else
1111 info->flags &= ~ASYNC_CTS_FLOW;
1112 if (cflag & CLOCAL)
1113 info->flags &= ~ASYNC_CHECK_CD;
1114 else {
1115 info->flags |= ASYNC_CHECK_CD;
1116 /* info->IER |= UART_IER_MSI; */
1117 }
1118
1119 /*
1120 * Set up parity check flag
1121 */
1122 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
1123
1124 info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
1125 if (I_INPCK(info->tty))
1126 info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
1127 if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
1128 info->read_status_mask |= UART_LSR_BI;
1129
1130 info->ignore_status_mask = 0;
1131 #if 0
1132 /* This should be safe, but for some broken bits of hardware... */
1133 if (I_IGNPAR(info->tty)) {
1134 info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
1135 info->read_status_mask |= UART_LSR_PE | UART_LSR_FE;
1136 }
1137 #endif
1138 if (I_IGNBRK(info->tty)) {
1139 info->ignore_status_mask |= UART_LSR_BI;
1140 info->read_status_mask |= UART_LSR_BI;
1141 /*
1142 * If we're ignore parity and break indicators, ignore
1143 * overruns too. (For real raw support).
1144 */
1145 if (I_IGNPAR(info->tty)) {
1146 info->ignore_status_mask |= UART_LSR_OE | \
1147 UART_LSR_PE | UART_LSR_FE;
1148 info->read_status_mask |= UART_LSR_OE | \
1149 UART_LSR_PE | UART_LSR_FE;
1150 }
1151 }
1152
1153 if (I_IXOFF(info->tty))
1154 flow1 |= 0x81;
1155
1156 spin_lock_irqsave(&info->lock, flags);
1157 /* set baud */
1158 serial_out(info, UART_ESI_CMD1, ESI_SET_BAUD);
1159 serial_out(info, UART_ESI_CMD2, quot >> 8);
1160 serial_out(info, UART_ESI_CMD2, quot & 0xff);
1161
1162 /* set data bits, parity, etc. */
1163 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1164 serial_out(info, UART_ESI_CMD2, UART_LCR);
1165 serial_out(info, UART_ESI_CMD2, cval);
1166
1167 /* Enable flow control */
1168 serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_CNTL);
1169 serial_out(info, UART_ESI_CMD2, flow1);
1170 serial_out(info, UART_ESI_CMD2, flow2);
1171
1172 /* set flow control characters (XON/XOFF only) */
1173 if (I_IXOFF(info->tty)) {
1174 serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_CHARS);
1175 serial_out(info, UART_ESI_CMD2, START_CHAR(info->tty));
1176 serial_out(info, UART_ESI_CMD2, STOP_CHAR(info->tty));
1177 serial_out(info, UART_ESI_CMD2, 0x10);
1178 serial_out(info, UART_ESI_CMD2, 0x21);
1179 switch (cflag & CSIZE) {
1180 case CS5:
1181 serial_out(info, UART_ESI_CMD2, 0x1f);
1182 break;
1183 case CS6:
1184 serial_out(info, UART_ESI_CMD2, 0x3f);
1185 break;
1186 case CS7:
1187 case CS8:
1188 serial_out(info, UART_ESI_CMD2, 0x7f);
1189 break;
1190 default:
1191 serial_out(info, UART_ESI_CMD2, 0xff);
1192 break;
1193 }
1194 }
1195
1196 /* Set high/low water */
1197 serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_LVL);
1198 serial_out(info, UART_ESI_CMD2, info->config.flow_off >> 8);
1199 serial_out(info, UART_ESI_CMD2, info->config.flow_off);
1200 serial_out(info, UART_ESI_CMD2, info->config.flow_on >> 8);
1201 serial_out(info, UART_ESI_CMD2, info->config.flow_on);
1202
1203 spin_unlock_irqrestore(&info->lock, flags);
1204 }
1205
1206 static void rs_put_char(struct tty_struct *tty, unsigned char ch)
1207 {
1208 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1209 unsigned long flags;
1210
1211 if (serial_paranoia_check(info, tty->name, "rs_put_char"))
1212 return;
1213
1214 if (!info->xmit_buf)
1215 return;
1216
1217 spin_lock_irqsave(&info->lock, flags);
1218 if (info->xmit_cnt < ESP_XMIT_SIZE - 1) {
1219 info->xmit_buf[info->xmit_head++] = ch;
1220 info->xmit_head &= ESP_XMIT_SIZE-1;
1221 info->xmit_cnt++;
1222 }
1223 spin_unlock_irqrestore(&info->lock, flags);
1224 }
1225
1226 static void rs_flush_chars(struct tty_struct *tty)
1227 {
1228 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1229 unsigned long flags;
1230
1231 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
1232 return;
1233
1234 spin_lock_irqsave(&info->lock, flags);
1235
1236 if (info->xmit_cnt <= 0 || tty->stopped || !info->xmit_buf)
1237 goto out;
1238
1239 if (!(info->IER & UART_IER_THRI)) {
1240 info->IER |= UART_IER_THRI;
1241 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1242 serial_out(info, UART_ESI_CMD2, info->IER);
1243 }
1244 out:
1245 spin_unlock_irqrestore(&info->lock, flags);
1246 }
1247
1248 static int rs_write(struct tty_struct * tty,
1249 const unsigned char *buf, int count)
1250 {
1251 int c, t, ret = 0;
1252 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1253 unsigned long flags;
1254
1255 if (serial_paranoia_check(info, tty->name, "rs_write"))
1256 return 0;
1257
1258 if (!info->xmit_buf)
1259 return 0;
1260
1261 while (1) {
1262 /* Thanks to R. Wolff for suggesting how to do this with */
1263 /* interrupts enabled */
1264
1265 c = count;
1266 t = ESP_XMIT_SIZE - info->xmit_cnt - 1;
1267
1268 if (t < c)
1269 c = t;
1270
1271 t = ESP_XMIT_SIZE - info->xmit_head;
1272
1273 if (t < c)
1274 c = t;
1275
1276 if (c <= 0)
1277 break;
1278
1279 memcpy(info->xmit_buf + info->xmit_head, buf, c);
1280
1281 info->xmit_head = (info->xmit_head + c) & (ESP_XMIT_SIZE-1);
1282 info->xmit_cnt += c;
1283 buf += c;
1284 count -= c;
1285 ret += c;
1286 }
1287
1288 spin_lock_irqsave(&info->lock, flags);
1289
1290 if (info->xmit_cnt && !tty->stopped && !(info->IER & UART_IER_THRI)) {
1291 info->IER |= UART_IER_THRI;
1292 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1293 serial_out(info, UART_ESI_CMD2, info->IER);
1294 }
1295
1296 spin_unlock_irqrestore(&info->lock, flags);
1297 return ret;
1298 }
1299
1300 static int rs_write_room(struct tty_struct *tty)
1301 {
1302 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1303 int ret;
1304 unsigned long flags;
1305
1306 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
1307 return 0;
1308
1309 spin_lock_irqsave(&info->lock, flags);
1310
1311 ret = ESP_XMIT_SIZE - info->xmit_cnt - 1;
1312 if (ret < 0)
1313 ret = 0;
1314 spin_unlock_irqrestore(&info->lock, flags);
1315 return ret;
1316 }
1317
1318 static int rs_chars_in_buffer(struct tty_struct *tty)
1319 {
1320 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1321
1322 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
1323 return 0;
1324 return info->xmit_cnt;
1325 }
1326
1327 static void rs_flush_buffer(struct tty_struct *tty)
1328 {
1329 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1330 unsigned long flags;
1331
1332 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
1333 return;
1334 spin_lock_irqsave(&info->lock, flags);
1335 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
1336 spin_unlock_irqrestore(&info->lock, flags);
1337 tty_wakeup(tty);
1338 }
1339
1340 /*
1341 * ------------------------------------------------------------
1342 * rs_throttle()
1343 *
1344 * This routine is called by the upper-layer tty layer to signal that
1345 * incoming characters should be throttled.
1346 * ------------------------------------------------------------
1347 */
1348 static void rs_throttle(struct tty_struct * tty)
1349 {
1350 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1351 unsigned long flags;
1352 #ifdef SERIAL_DEBUG_THROTTLE
1353 char buf[64];
1354
1355 printk("throttle %s: %d....\n", tty_name(tty, buf),
1356 tty->ldisc.chars_in_buffer(tty));
1357 #endif
1358
1359 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
1360 return;
1361
1362 spin_lock_irqsave(&info->lock, flags);
1363 info->IER &= ~UART_IER_RDI;
1364 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1365 serial_out(info, UART_ESI_CMD2, info->IER);
1366 serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
1367 serial_out(info, UART_ESI_CMD2, 0x00);
1368 spin_unlock_irqrestore(&info->lock, flags);
1369 }
1370
1371 static void rs_unthrottle(struct tty_struct * tty)
1372 {
1373 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1374 unsigned long flags;
1375 #ifdef SERIAL_DEBUG_THROTTLE
1376 char buf[64];
1377
1378 printk("unthrottle %s: %d....\n", tty_name(tty, buf),
1379 tty->ldisc.chars_in_buffer(tty));
1380 #endif
1381
1382 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
1383 return;
1384
1385 spin_lock_irqsave(&info->lock, flags);
1386 info->IER |= UART_IER_RDI;
1387 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
1388 serial_out(info, UART_ESI_CMD2, info->IER);
1389 serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
1390 serial_out(info, UART_ESI_CMD2, info->config.rx_timeout);
1391 spin_unlock_irqrestore(&info->lock, flags);
1392 }
1393
1394 /*
1395 * ------------------------------------------------------------
1396 * rs_ioctl() and friends
1397 * ------------------------------------------------------------
1398 */
1399
1400 static int get_serial_info(struct esp_struct * info,
1401 struct serial_struct __user *retinfo)
1402 {
1403 struct serial_struct tmp;
1404
1405 memset(&tmp, 0, sizeof(tmp));
1406 tmp.type = PORT_16550A;
1407 tmp.line = info->line;
1408 tmp.port = info->port;
1409 tmp.irq = info->irq;
1410 tmp.flags = info->flags;
1411 tmp.xmit_fifo_size = 1024;
1412 tmp.baud_base = BASE_BAUD;
1413 tmp.close_delay = info->close_delay;
1414 tmp.closing_wait = info->closing_wait;
1415 tmp.custom_divisor = info->custom_divisor;
1416 tmp.hub6 = 0;
1417 if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
1418 return -EFAULT;
1419 return 0;
1420 }
1421
1422 static int get_esp_config(struct esp_struct * info,
1423 struct hayes_esp_config __user *retinfo)
1424 {
1425 struct hayes_esp_config tmp;
1426
1427 if (!retinfo)
1428 return -EFAULT;
1429
1430 memset(&tmp, 0, sizeof(tmp));
1431 tmp.rx_timeout = info->config.rx_timeout;
1432 tmp.rx_trigger = info->config.rx_trigger;
1433 tmp.tx_trigger = info->config.tx_trigger;
1434 tmp.flow_off = info->config.flow_off;
1435 tmp.flow_on = info->config.flow_on;
1436 tmp.pio_threshold = info->config.pio_threshold;
1437 tmp.dma_channel = (info->stat_flags & ESP_STAT_NEVER_DMA ? 0 : dma);
1438
1439 return copy_to_user(retinfo, &tmp, sizeof(*retinfo)) ? -EFAULT : 0;
1440 }
1441
1442 static int set_serial_info(struct esp_struct * info,
1443 struct serial_struct __user *new_info)
1444 {
1445 struct serial_struct new_serial;
1446 struct esp_struct old_info;
1447 unsigned int change_irq;
1448 int retval = 0;
1449 struct esp_struct *current_async;
1450
1451 if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
1452 return -EFAULT;
1453 old_info = *info;
1454
1455 if ((new_serial.type != PORT_16550A) ||
1456 (new_serial.hub6) ||
1457 (info->port != new_serial.port) ||
1458 (new_serial.baud_base != BASE_BAUD) ||
1459 (new_serial.irq > 15) ||
1460 (new_serial.irq < 2) ||
1461 (new_serial.irq == 6) ||
1462 (new_serial.irq == 8) ||
1463 (new_serial.irq == 13))
1464 return -EINVAL;
1465
1466 change_irq = new_serial.irq != info->irq;
1467
1468 if (change_irq && (info->line % 8))
1469 return -EINVAL;
1470
1471 if (!capable(CAP_SYS_ADMIN)) {
1472 if (change_irq ||
1473 (new_serial.close_delay != info->close_delay) ||
1474 ((new_serial.flags & ~ASYNC_USR_MASK) !=
1475 (info->flags & ~ASYNC_USR_MASK)))
1476 return -EPERM;
1477 info->flags = ((info->flags & ~ASYNC_USR_MASK) |
1478 (new_serial.flags & ASYNC_USR_MASK));
1479 info->custom_divisor = new_serial.custom_divisor;
1480 } else {
1481 if (new_serial.irq == 2)
1482 new_serial.irq = 9;
1483
1484 if (change_irq) {
1485 current_async = ports;
1486
1487 while (current_async) {
1488 if ((current_async->line >= info->line) &&
1489 (current_async->line < (info->line + 8))) {
1490 if (current_async == info) {
1491 if (current_async->count > 1)
1492 return -EBUSY;
1493 } else if (current_async->count)
1494 return -EBUSY;
1495 }
1496
1497 current_async = current_async->next_port;
1498 }
1499 }
1500
1501 /*
1502 * OK, past this point, all the error checking has been done.
1503 * At this point, we start making changes.....
1504 */
1505
1506 info->flags = ((info->flags & ~ASYNC_FLAGS) |
1507 (new_serial.flags & ASYNC_FLAGS));
1508 info->custom_divisor = new_serial.custom_divisor;
1509 info->close_delay = new_serial.close_delay * HZ/100;
1510 info->closing_wait = new_serial.closing_wait * HZ/100;
1511
1512 if (change_irq) {
1513 /*
1514 * We need to shutdown the serial port at the old
1515 * port/irq combination.
1516 */
1517 shutdown(info);
1518
1519 current_async = ports;
1520
1521 while (current_async) {
1522 if ((current_async->line >= info->line) &&
1523 (current_async->line < (info->line + 8)))
1524 current_async->irq = new_serial.irq;
1525
1526 current_async = current_async->next_port;
1527 }
1528
1529 serial_out(info, UART_ESI_CMD1, ESI_SET_ENH_IRQ);
1530 if (info->irq == 9)
1531 serial_out(info, UART_ESI_CMD2, 0x02);
1532 else
1533 serial_out(info, UART_ESI_CMD2, info->irq);
1534 }
1535 }
1536
1537 if (info->flags & ASYNC_INITIALIZED) {
1538 if (((old_info.flags & ASYNC_SPD_MASK) !=
1539 (info->flags & ASYNC_SPD_MASK)) ||
1540 (old_info.custom_divisor != info->custom_divisor)) {
1541 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
1542 info->tty->alt_speed = 57600;
1543 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
1544 info->tty->alt_speed = 115200;
1545 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
1546 info->tty->alt_speed = 230400;
1547 if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
1548 info->tty->alt_speed = 460800;
1549 change_speed(info);
1550 }
1551 } else
1552 retval = startup(info);
1553
1554 return retval;
1555 }
1556
1557 static int set_esp_config(struct esp_struct * info,
1558 struct hayes_esp_config __user * new_info)
1559 {
1560 struct hayes_esp_config new_config;
1561 unsigned int change_dma;
1562 int retval = 0;
1563 struct esp_struct *current_async;
1564 unsigned long flags;
1565
1566 /* Perhaps a non-sysadmin user should be able to do some of these */
1567 /* operations. I haven't decided yet. */
1568
1569 if (!capable(CAP_SYS_ADMIN))
1570 return -EPERM;
1571
1572 if (copy_from_user(&new_config, new_info, sizeof(new_config)))
1573 return -EFAULT;
1574
1575 if ((new_config.flow_on >= new_config.flow_off) ||
1576 (new_config.rx_trigger < 1) ||
1577 (new_config.tx_trigger < 1) ||
1578 (new_config.flow_off < 1) ||
1579 (new_config.flow_on < 1) ||
1580 (new_config.rx_trigger > 1023) ||
1581 (new_config.tx_trigger > 1023) ||
1582 (new_config.flow_off > 1023) ||
1583 (new_config.flow_on > 1023) ||
1584 (new_config.pio_threshold < 0) ||
1585 (new_config.pio_threshold > 1024))
1586 return -EINVAL;
1587
1588 if ((new_config.dma_channel != 1) && (new_config.dma_channel != 3))
1589 new_config.dma_channel = 0;
1590
1591 if (info->stat_flags & ESP_STAT_NEVER_DMA)
1592 change_dma = new_config.dma_channel;
1593 else
1594 change_dma = (new_config.dma_channel != dma);
1595
1596 if (change_dma) {
1597 if (new_config.dma_channel) {
1598 /* PIO mode to DMA mode transition OR */
1599 /* change current DMA channel */
1600
1601 current_async = ports;
1602
1603 while (current_async) {
1604 if (current_async == info) {
1605 if (current_async->count > 1)
1606 return -EBUSY;
1607 } else if (current_async->count)
1608 return -EBUSY;
1609
1610 current_async =
1611 current_async->next_port;
1612 }
1613
1614 shutdown(info);
1615 dma = new_config.dma_channel;
1616 info->stat_flags &= ~ESP_STAT_NEVER_DMA;
1617
1618 /* all ports must use the same DMA channel */
1619
1620 spin_lock_irqsave(&info->lock, flags);
1621 current_async = ports;
1622
1623 while (current_async) {
1624 esp_basic_init(current_async);
1625 current_async = current_async->next_port;
1626 }
1627 spin_unlock_irqrestore(&info->lock, flags);
1628 } else {
1629 /* DMA mode to PIO mode only */
1630
1631 if (info->count > 1)
1632 return -EBUSY;
1633
1634 shutdown(info);
1635 spin_lock_irqsave(&info->lock, flags);
1636 info->stat_flags |= ESP_STAT_NEVER_DMA;
1637 esp_basic_init(info);
1638 spin_unlock_irqrestore(&info->lock, flags);
1639 }
1640 }
1641
1642 info->config.pio_threshold = new_config.pio_threshold;
1643
1644 if ((new_config.flow_off != info->config.flow_off) ||
1645 (new_config.flow_on != info->config.flow_on)) {
1646 unsigned long flags;
1647
1648 info->config.flow_off = new_config.flow_off;
1649 info->config.flow_on = new_config.flow_on;
1650
1651 spin_lock_irqsave(&info->lock, flags);
1652 serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_LVL);
1653 serial_out(info, UART_ESI_CMD2, new_config.flow_off >> 8);
1654 serial_out(info, UART_ESI_CMD2, new_config.flow_off);
1655 serial_out(info, UART_ESI_CMD2, new_config.flow_on >> 8);
1656 serial_out(info, UART_ESI_CMD2, new_config.flow_on);
1657 spin_unlock_irqrestore(&info->lock, flags);
1658 }
1659
1660 if ((new_config.rx_trigger != info->config.rx_trigger) ||
1661 (new_config.tx_trigger != info->config.tx_trigger)) {
1662 unsigned long flags;
1663
1664 info->config.rx_trigger = new_config.rx_trigger;
1665 info->config.tx_trigger = new_config.tx_trigger;
1666 spin_lock_irqsave(&info->lock, flags);
1667 serial_out(info, UART_ESI_CMD1, ESI_SET_TRIGGER);
1668 serial_out(info, UART_ESI_CMD2,
1669 new_config.rx_trigger >> 8);
1670 serial_out(info, UART_ESI_CMD2, new_config.rx_trigger);
1671 serial_out(info, UART_ESI_CMD2,
1672 new_config.tx_trigger >> 8);
1673 serial_out(info, UART_ESI_CMD2, new_config.tx_trigger);
1674 spin_unlock_irqrestore(&info->lock, flags);
1675 }
1676
1677 if (new_config.rx_timeout != info->config.rx_timeout) {
1678 unsigned long flags;
1679
1680 info->config.rx_timeout = new_config.rx_timeout;
1681 spin_lock_irqsave(&info->lock, flags);
1682
1683 if (info->IER & UART_IER_RDI) {
1684 serial_out(info, UART_ESI_CMD1,
1685 ESI_SET_RX_TIMEOUT);
1686 serial_out(info, UART_ESI_CMD2,
1687 new_config.rx_timeout);
1688 }
1689
1690 spin_unlock_irqrestore(&info->lock, flags);
1691 }
1692
1693 if (!(info->flags & ASYNC_INITIALIZED))
1694 retval = startup(info);
1695
1696 return retval;
1697 }
1698
1699 /*
1700 * get_lsr_info - get line status register info
1701 *
1702 * Purpose: Let user call ioctl() to get info when the UART physically
1703 * is emptied. On bus types like RS485, the transmitter must
1704 * release the bus after transmitting. This must be done when
1705 * the transmit shift register is empty, not be done when the
1706 * transmit holding register is empty. This functionality
1707 * allows an RS485 driver to be written in user space.
1708 */
1709 static int get_lsr_info(struct esp_struct * info, unsigned int __user *value)
1710 {
1711 unsigned char status;
1712 unsigned int result;
1713 unsigned long flags;
1714
1715 spin_lock_irqsave(&info->lock, flags);
1716 serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
1717 status = serial_in(info, UART_ESI_STAT1);
1718 spin_unlock_irqrestore(&info->lock, flags);
1719 result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
1720 return put_user(result,value);
1721 }
1722
1723
1724 static int esp_tiocmget(struct tty_struct *tty, struct file *file)
1725 {
1726 struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1727 unsigned char control, status;
1728 unsigned long flags;
1729
1730 if (serial_paranoia_check(info, tty->name, __FUNCTION__))
1731 return -ENODEV;
1732 if (tty->flags & (1 << TTY_IO_ERROR))
1733 return -EIO;
1734
1735 control = info->MCR;
1736
1737 spin_lock_irqsave(&info->lock, flags);
1738 serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
1739 status = serial_in(info, UART_ESI_STAT2);
1740 spin_unlock_irqrestore(&info->lock, flags);
1741
1742 return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
1743 | ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
1744 | ((status & UART_MSR_DCD) ? TIOCM_CAR : 0)
1745 | ((status & UART_MSR_RI) ? TIOCM_RNG : 0)
1746 | ((status & UART_MSR_DSR) ? TIOCM_DSR : 0)
1747 | ((status & UART_MSR_CTS) ? TIOCM_CTS : 0);
1748 }
1749
1750 static int esp_tiocmset(struct tty_struct *tty, struct file *file,
1751 unsigned int set, unsigned int clear)
1752 {
1753 struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1754 unsigned long flags;
1755
1756 if (serial_paranoia_check(info, tty->name, __FUNCTION__))
1757 return -ENODEV;
1758 if (tty->flags & (1 << TTY_IO_ERROR))
1759 return -EIO;
1760
1761 spin_lock_irqsave(&info->lock, flags);
1762
1763 if (set & TIOCM_RTS)
1764 info->MCR |= UART_MCR_RTS;
1765 if (set & TIOCM_DTR)
1766 info->MCR |= UART_MCR_DTR;
1767
1768 if (clear & TIOCM_RTS)
1769 info->MCR &= ~UART_MCR_RTS;
1770 if (clear & TIOCM_DTR)
1771 info->MCR &= ~UART_MCR_DTR;
1772
1773 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1774 serial_out(info, UART_ESI_CMD2, UART_MCR);
1775 serial_out(info, UART_ESI_CMD2, info->MCR);
1776
1777 spin_unlock_irqrestore(&info->lock, flags);
1778 return 0;
1779 }
1780
1781 /*
1782 * rs_break() --- routine which turns the break handling on or off
1783 */
1784 static void esp_break(struct tty_struct *tty, int break_state)
1785 {
1786 struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1787 unsigned long flags;
1788
1789 if (serial_paranoia_check(info, tty->name, "esp_break"))
1790 return;
1791
1792 if (break_state == -1) {
1793 spin_lock_irqsave(&info->lock, flags);
1794 serial_out(info, UART_ESI_CMD1, ESI_ISSUE_BREAK);
1795 serial_out(info, UART_ESI_CMD2, 0x01);
1796 spin_unlock_irqrestore(&info->lock, flags);
1797
1798 /* FIXME - new style wait needed here */
1799 interruptible_sleep_on(&info->break_wait);
1800 } else {
1801 spin_lock_irqsave(&info->lock, flags);
1802 serial_out(info, UART_ESI_CMD1, ESI_ISSUE_BREAK);
1803 serial_out(info, UART_ESI_CMD2, 0x00);
1804 spin_unlock_irqrestore(&info->lock, flags);
1805 }
1806 }
1807
1808 static int rs_ioctl(struct tty_struct *tty, struct file * file,
1809 unsigned int cmd, unsigned long arg)
1810 {
1811 struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1812 struct async_icount cprev, cnow; /* kernel counter temps */
1813 struct serial_icounter_struct __user *p_cuser; /* user space */
1814 void __user *argp = (void __user *)arg;
1815 unsigned long flags;
1816
1817 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
1818 return -ENODEV;
1819
1820 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1821 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
1822 (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT) &&
1823 (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT) &&
1824 (cmd != TIOCGHAYESESP) && (cmd != TIOCSHAYESESP)) {
1825 if (tty->flags & (1 << TTY_IO_ERROR))
1826 return -EIO;
1827 }
1828
1829 switch (cmd) {
1830 case TIOCGSERIAL:
1831 return get_serial_info(info, argp);
1832 case TIOCSSERIAL:
1833 return set_serial_info(info, argp);
1834 case TIOCSERCONFIG:
1835 /* do not reconfigure after initial configuration */
1836 return 0;
1837
1838 case TIOCSERGWILD:
1839 return put_user(0L, (unsigned long __user *)argp);
1840
1841 case TIOCSERGETLSR: /* Get line status register */
1842 return get_lsr_info(info, argp);
1843
1844 case TIOCSERSWILD:
1845 if (!capable(CAP_SYS_ADMIN))
1846 return -EPERM;
1847 return 0;
1848
1849 /*
1850 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1851 * - mask passed in arg for lines of interest
1852 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1853 * Caller should use TIOCGICOUNT to see which one it was
1854 */
1855 case TIOCMIWAIT:
1856 spin_lock_irqsave(&info->lock, flags);
1857 cprev = info->icount; /* note the counters on entry */
1858 spin_unlock_irqrestore(&info->lock, flags);
1859 while (1) {
1860 /* FIXME: convert to new style wakeup */
1861 interruptible_sleep_on(&info->delta_msr_wait);
1862 /* see if a signal did it */
1863 if (signal_pending(current))
1864 return -ERESTARTSYS;
1865 spin_lock_irqsave(&info->lock, flags);
1866 cnow = info->icount; /* atomic copy */
1867 spin_unlock_irqrestore(&info->lock, flags);
1868 if (cnow.rng == cprev.rng &&
1869 cnow.dsr == cprev.dsr &&
1870 cnow.dcd == cprev.dcd &&
1871 cnow.cts == cprev.cts)
1872 return -EIO; /* no change => error */
1873 if (((arg & TIOCM_RNG) &&
1874 (cnow.rng != cprev.rng)) ||
1875 ((arg & TIOCM_DSR) &&
1876 (cnow.dsr != cprev.dsr)) ||
1877 ((arg & TIOCM_CD) &&
1878 (cnow.dcd != cprev.dcd)) ||
1879 ((arg & TIOCM_CTS) &&
1880 (cnow.cts != cprev.cts)) ) {
1881 return 0;
1882 }
1883 cprev = cnow;
1884 }
1885 /* NOTREACHED */
1886
1887 /*
1888 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1889 * Return: write counters to the user passed counter struct
1890 * NB: both 1->0 and 0->1 transitions are counted except for
1891 * RI where only 0->1 is counted.
1892 */
1893 case TIOCGICOUNT:
1894 spin_lock_irqsave(&info->lock, flags);
1895 cnow = info->icount;
1896 spin_unlock_irqrestore(&info->lock, flags);
1897 p_cuser = argp;
1898 if (put_user(cnow.cts, &p_cuser->cts) ||
1899 put_user(cnow.dsr, &p_cuser->dsr) ||
1900 put_user(cnow.rng, &p_cuser->rng) ||
1901 put_user(cnow.dcd, &p_cuser->dcd))
1902 return -EFAULT;
1903
1904 return 0;
1905 case TIOCGHAYESESP:
1906 return get_esp_config(info, argp);
1907 case TIOCSHAYESESP:
1908 return set_esp_config(info, argp);
1909
1910 default:
1911 return -ENOIOCTLCMD;
1912 }
1913 return 0;
1914 }
1915
1916 static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
1917 {
1918 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
1919 unsigned long flags;
1920
1921 if ( (tty->termios->c_cflag == old_termios->c_cflag)
1922 && ( RELEVANT_IFLAG(tty->termios->c_iflag)
1923 == RELEVANT_IFLAG(old_termios->c_iflag)))
1924 return;
1925
1926 change_speed(info);
1927
1928 spin_lock_irqsave(&info->lock, flags);
1929
1930 /* Handle transition to B0 status */
1931 if ((old_termios->c_cflag & CBAUD) &&
1932 !(tty->termios->c_cflag & CBAUD)) {
1933 info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
1934 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1935 serial_out(info, UART_ESI_CMD2, UART_MCR);
1936 serial_out(info, UART_ESI_CMD2, info->MCR);
1937 }
1938
1939 /* Handle transition away from B0 status */
1940 if (!(old_termios->c_cflag & CBAUD) &&
1941 (tty->termios->c_cflag & CBAUD)) {
1942 info->MCR |= (UART_MCR_DTR | UART_MCR_RTS);
1943 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
1944 serial_out(info, UART_ESI_CMD2, UART_MCR);
1945 serial_out(info, UART_ESI_CMD2, info->MCR);
1946 }
1947
1948 spin_unlock_irqrestore(&info->lock, flags);
1949
1950 /* Handle turning of CRTSCTS */
1951 if ((old_termios->c_cflag & CRTSCTS) &&
1952 !(tty->termios->c_cflag & CRTSCTS)) {
1953 rs_start(tty);
1954 }
1955 }
1956
1957 /*
1958 * ------------------------------------------------------------
1959 * rs_close()
1960 *
1961 * This routine is called when the serial port gets closed. First, we
1962 * wait for the last remaining data to be sent. Then, we unlink its
1963 * async structure from the interrupt chain if necessary, and we free
1964 * that IRQ if nothing is left in the chain.
1965 * ------------------------------------------------------------
1966 */
1967 static void rs_close(struct tty_struct *tty, struct file * filp)
1968 {
1969 struct esp_struct * info = (struct esp_struct *)tty->driver_data;
1970 unsigned long flags;
1971
1972 if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
1973 return;
1974
1975 spin_lock_irqsave(&info->lock, flags);
1976
1977 if (tty_hung_up_p(filp)) {
1978 DBG_CNT("before DEC-hung");
1979 goto out;
1980 }
1981
1982 #ifdef SERIAL_DEBUG_OPEN
1983 printk("rs_close ttys%d, count = %d\n", info->line, info->count);
1984 #endif
1985 if ((tty->count == 1) && (info->count != 1)) {
1986 /*
1987 * Uh, oh. tty->count is 1, which means that the tty
1988 * structure will be freed. Info->count should always
1989 * be one in these conditions. If it's greater than
1990 * one, we've got real problems, since it means the
1991 * serial port won't be shutdown.
1992 */
1993 printk("rs_close: bad serial port count; tty->count is 1, "
1994 "info->count is %d\n", info->count);
1995 info->count = 1;
1996 }
1997 if (--info->count < 0) {
1998 printk("rs_close: bad serial port count for ttys%d: %d\n",
1999 info->line, info->count);
2000 info->count = 0;
2001 }
2002 if (info->count) {
2003 DBG_CNT("before DEC-2");
2004 goto out;
2005 }
2006 info->flags |= ASYNC_CLOSING;
2007
2008 spin_unlock_irqrestore(&info->lock, flags);
2009 /*
2010 * Now we wait for the transmit buffer to clear; and we notify
2011 * the line discipline to only process XON/XOFF characters.
2012 */
2013 tty->closing = 1;
2014 if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
2015 tty_wait_until_sent(tty, info->closing_wait);
2016 /*
2017 * At this point we stop accepting input. To do this, we
2018 * disable the receive line status interrupts, and tell the
2019 * interrupt driver to stop checking the data ready bit in the
2020 * line status register.
2021 */
2022 /* info->IER &= ~UART_IER_RLSI; */
2023 info->IER &= ~UART_IER_RDI;
2024 info->read_status_mask &= ~UART_LSR_DR;
2025 if (info->flags & ASYNC_INITIALIZED) {
2026
2027 spin_lock_irqsave(&info->lock, flags);
2028 serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
2029 serial_out(info, UART_ESI_CMD2, info->IER);
2030
2031 /* disable receive timeout */
2032 serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
2033 serial_out(info, UART_ESI_CMD2, 0x00);
2034
2035 spin_unlock_irqrestore(&info->lock, flags);
2036
2037 /*
2038 * Before we drop DTR, make sure the UART transmitter
2039 * has completely drained; this is especially
2040 * important if there is a transmit FIFO!
2041 */
2042 rs_wait_until_sent(tty, info->timeout);
2043 }
2044 shutdown(info);
2045 if (tty->driver->flush_buffer)
2046 tty->driver->flush_buffer(tty);
2047 tty_ldisc_flush(tty);
2048 tty->closing = 0;
2049 info->event = 0;
2050 info->tty = NULL;
2051
2052 if (info->blocked_open) {
2053 if (info->close_delay) {
2054 msleep_interruptible(jiffies_to_msecs(info->close_delay));
2055 }
2056 wake_up_interruptible(&info->open_wait);
2057 }
2058 info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
2059 wake_up_interruptible(&info->close_wait);
2060 return;
2061
2062 out:
2063 spin_unlock_irqrestore(&info->lock, flags);
2064 }
2065
2066 static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
2067 {
2068 struct esp_struct *info = (struct esp_struct *)tty->driver_data;
2069 unsigned long orig_jiffies, char_time;
2070 unsigned long flags;
2071
2072 if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
2073 return;
2074
2075 orig_jiffies = jiffies;
2076 char_time = ((info->timeout - HZ / 50) / 1024) / 5;
2077
2078 if (!char_time)
2079 char_time = 1;
2080
2081 spin_lock_irqsave(&info->lock, flags);
2082 serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
2083 serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
2084
2085 while ((serial_in(info, UART_ESI_STAT1) != 0x03) ||
2086 (serial_in(info, UART_ESI_STAT2) != 0xff)) {
2087
2088 spin_unlock_irqrestore(&info->lock, flags);
2089 msleep_interruptible(jiffies_to_msecs(char_time));
2090
2091 if (signal_pending(current))
2092 break;
2093
2094 if (timeout && time_after(jiffies, orig_jiffies + timeout))
2095 break;
2096
2097 spin_lock_irqsave(&info->lock, flags);
2098 serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
2099 serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
2100 }
2101 spin_unlock_irqrestore(&info->lock, flags);
2102 set_current_state(TASK_RUNNING);
2103 }
2104
2105 /*
2106 * esp_hangup() --- called by tty_hangup() when a hangup is signaled.
2107 */
2108 static void esp_hangup(struct tty_struct *tty)
2109 {
2110 struct esp_struct * info = (struct esp_struct *)tty->driver_data;
2111
2112 if (serial_paranoia_check(info, tty->name, "esp_hangup"))
2113 return;
2114
2115 rs_flush_buffer(tty);
2116 shutdown(info);
2117 info->event = 0;
2118 info->count = 0;
2119 info->flags &= ~ASYNC_NORMAL_ACTIVE;
2120 info->tty = NULL;
2121 wake_up_interruptible(&info->open_wait);
2122 }
2123
2124 /*
2125 * ------------------------------------------------------------
2126 * esp_open() and friends
2127 * ------------------------------------------------------------
2128 */
2129 static int block_til_ready(struct tty_struct *tty, struct file * filp,
2130 struct esp_struct *info)
2131 {
2132 DECLARE_WAITQUEUE(wait, current);
2133 int retval;
2134 int do_clocal = 0;
2135 unsigned long flags;
2136
2137 /*
2138 * If the device is in the middle of being closed, then block
2139 * until it's done, and then try again.
2140 */
2141 if (tty_hung_up_p(filp) ||
2142 (info->flags & ASYNC_CLOSING)) {
2143 if (info->flags & ASYNC_CLOSING)
2144 interruptible_sleep_on(&info->close_wait);
2145 #ifdef SERIAL_DO_RESTART
2146 if (info->flags & ASYNC_HUP_NOTIFY)
2147 return -EAGAIN;
2148 else
2149 return -ERESTARTSYS;
2150 #else
2151 return -EAGAIN;
2152 #endif
2153 }
2154
2155 /*
2156 * If non-blocking mode is set, or the port is not enabled,
2157 * then make the check up front and then exit.
2158 */
2159 if ((filp->f_flags & O_NONBLOCK) ||
2160 (tty->flags & (1 << TTY_IO_ERROR))) {
2161 info->flags |= ASYNC_NORMAL_ACTIVE;
2162 return 0;
2163 }
2164
2165 if (tty->termios->c_cflag & CLOCAL)
2166 do_clocal = 1;
2167
2168 /*
2169 * Block waiting for the carrier detect and the line to become
2170 * free (i.e., not in use by the callout). While we are in
2171 * this loop, info->count is dropped by one, so that
2172 * rs_close() knows when to free things. We restore it upon
2173 * exit, either normal or abnormal.
2174 */
2175 retval = 0;
2176 add_wait_queue(&info->open_wait, &wait);
2177 #ifdef SERIAL_DEBUG_OPEN
2178 printk("block_til_ready before block: ttys%d, count = %d\n",
2179 info->line, info->count);
2180 #endif
2181 spin_lock_irqsave(&info->lock, flags);
2182 if (!tty_hung_up_p(filp))
2183 info->count--;
2184 info->blocked_open++;
2185 while (1) {
2186 if ((tty->termios->c_cflag & CBAUD)) {
2187 unsigned int scratch;
2188
2189 serial_out(info, UART_ESI_CMD1, ESI_READ_UART);
2190 serial_out(info, UART_ESI_CMD2, UART_MCR);
2191 scratch = serial_in(info, UART_ESI_STAT1);
2192 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
2193 serial_out(info, UART_ESI_CMD2, UART_MCR);
2194 serial_out(info, UART_ESI_CMD2,
2195 scratch | UART_MCR_DTR | UART_MCR_RTS);
2196 }
2197 set_current_state(TASK_INTERRUPTIBLE);
2198 if (tty_hung_up_p(filp) ||
2199 !(info->flags & ASYNC_INITIALIZED)) {
2200 #ifdef SERIAL_DO_RESTART
2201 if (info->flags & ASYNC_HUP_NOTIFY)
2202 retval = -EAGAIN;
2203 else
2204 retval = -ERESTARTSYS;
2205 #else
2206 retval = -EAGAIN;
2207 #endif
2208 break;
2209 }
2210
2211 serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
2212 if (serial_in(info, UART_ESI_STAT2) & UART_MSR_DCD)
2213 do_clocal = 1;
2214
2215 if (!(info->flags & ASYNC_CLOSING) &&
2216 (do_clocal))
2217 break;
2218 if (signal_pending(current)) {
2219 retval = -ERESTARTSYS;
2220 break;
2221 }
2222 #ifdef SERIAL_DEBUG_OPEN
2223 printk("block_til_ready blocking: ttys%d, count = %d\n",
2224 info->line, info->count);
2225 #endif
2226 spin_unlock_irqrestore(&info->lock, flags);
2227 schedule();
2228 spin_lock_irqsave(&info->lock, flags);
2229 }
2230 set_current_state(TASK_RUNNING);
2231 remove_wait_queue(&info->open_wait, &wait);
2232 if (!tty_hung_up_p(filp))
2233 info->count++;
2234 info->blocked_open--;
2235 spin_unlock_irqrestore(&info->lock, flags);
2236 #ifdef SERIAL_DEBUG_OPEN
2237 printk("block_til_ready after blocking: ttys%d, count = %d\n",
2238 info->line, info->count);
2239 #endif
2240 if (retval)
2241 return retval;
2242 info->flags |= ASYNC_NORMAL_ACTIVE;
2243 return 0;
2244 }
2245
2246 /*
2247 * This routine is called whenever a serial port is opened. It
2248 * enables interrupts for a serial port, linking in its async structure into
2249 * the IRQ chain. It also performs the serial-specific
2250 * initialization for the tty structure.
2251 */
2252 static int esp_open(struct tty_struct *tty, struct file * filp)
2253 {
2254 struct esp_struct *info;
2255 int retval, line;
2256 unsigned long flags;
2257
2258 line = tty->index;
2259 if ((line < 0) || (line >= NR_PORTS))
2260 return -ENODEV;
2261
2262 /* find the port in the chain */
2263
2264 info = ports;
2265
2266 while (info && (info->line != line))
2267 info = info->next_port;
2268
2269 if (!info) {
2270 serial_paranoia_check(info, tty->name, "esp_open");
2271 return -ENODEV;
2272 }
2273
2274 #ifdef SERIAL_DEBUG_OPEN
2275 printk("esp_open %s, count = %d\n", tty->name, info->count);
2276 #endif
2277 spin_lock_irqsave(&info->lock, flags);
2278 info->count++;
2279 tty->driver_data = info;
2280 info->tty = tty;
2281
2282 spin_unlock_irqrestore(&info->lock, flags);
2283
2284 /*
2285 * Start up serial port
2286 */
2287 retval = startup(info);
2288 if (retval)
2289 return retval;
2290
2291 retval = block_til_ready(tty, filp, info);
2292 if (retval) {
2293 #ifdef SERIAL_DEBUG_OPEN
2294 printk("esp_open returning after block_til_ready with %d\n",
2295 retval);
2296 #endif
2297 return retval;
2298 }
2299
2300 #ifdef SERIAL_DEBUG_OPEN
2301 printk("esp_open %s successful...", tty->name);
2302 #endif
2303 return 0;
2304 }
2305
2306 /*
2307 * ---------------------------------------------------------------------
2308 * espserial_init() and friends
2309 *
2310 * espserial_init() is called at boot-time to initialize the serial driver.
2311 * ---------------------------------------------------------------------
2312 */
2313
2314 /*
2315 * This routine prints out the appropriate serial driver version
2316 * number, and identifies which options were configured into this
2317 * driver.
2318 */
2319
2320 static inline void show_serial_version(void)
2321 {
2322 printk(KERN_INFO "%s version %s (DMA %u)\n",
2323 serial_name, serial_version, dma);
2324 }
2325
2326 /*
2327 * This routine is called by espserial_init() to initialize a specific serial
2328 * port.
2329 */
2330 static inline int autoconfig(struct esp_struct * info)
2331 {
2332 int port_detected = 0;
2333 unsigned long flags;
2334
2335 if (!request_region(info->port, REGION_SIZE, "esp serial"))
2336 return -EIO;
2337
2338 spin_lock_irqsave(&info->lock, flags);
2339 /*
2340 * Check for ESP card
2341 */
2342
2343 if (serial_in(info, UART_ESI_BASE) == 0xf3) {
2344 serial_out(info, UART_ESI_CMD1, 0x00);
2345 serial_out(info, UART_ESI_CMD1, 0x01);
2346
2347 if ((serial_in(info, UART_ESI_STAT2) & 0x70) == 0x20) {
2348 port_detected = 1;
2349
2350 if (!(info->irq)) {
2351 serial_out(info, UART_ESI_CMD1, 0x02);
2352
2353 if (serial_in(info, UART_ESI_STAT1) & 0x01)
2354 info->irq = 3;
2355 else
2356 info->irq = 4;
2357 }
2358
2359
2360 /* put card in enhanced mode */
2361 /* this prevents access through */
2362 /* the "old" IO ports */
2363 esp_basic_init(info);
2364
2365 /* clear out MCR */
2366 serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
2367 serial_out(info, UART_ESI_CMD2, UART_MCR);
2368 serial_out(info, UART_ESI_CMD2, 0x00);
2369 }
2370 }
2371 if (!port_detected)
2372 release_region(info->port, REGION_SIZE);
2373
2374 spin_unlock_irqrestore(&info->lock, flags);
2375 return (port_detected);
2376 }
2377
2378 static const struct tty_operations esp_ops = {
2379 .open = esp_open,
2380 .close = rs_close,
2381 .write = rs_write,
2382 .put_char = rs_put_char,
2383 .flush_chars = rs_flush_chars,
2384 .write_room = rs_write_room,
2385 .chars_in_buffer = rs_chars_in_buffer,
2386 .flush_buffer = rs_flush_buffer,
2387 .ioctl = rs_ioctl,
2388 .throttle = rs_throttle,
2389 .unthrottle = rs_unthrottle,
2390 .set_termios = rs_set_termios,
2391 .stop = rs_stop,
2392 .start = rs_start,
2393 .hangup = esp_hangup,
2394 .break_ctl = esp_break,
2395 .wait_until_sent = rs_wait_until_sent,
2396 .tiocmget = esp_tiocmget,
2397 .tiocmset = esp_tiocmset,
2398 };
2399
2400 /*
2401 * The serial driver boot-time initialization code!
2402 */
2403 static int __init espserial_init(void)
2404 {
2405 int i, offset;
2406 struct esp_struct * info;
2407 struct esp_struct *last_primary = NULL;
2408 int esp[] = {0x100,0x140,0x180,0x200,0x240,0x280,0x300,0x380};
2409
2410 esp_driver = alloc_tty_driver(NR_PORTS);
2411 if (!esp_driver)
2412 return -ENOMEM;
2413
2414 for (i = 0; i < NR_PRIMARY; i++) {
2415 if (irq[i] != 0) {
2416 if ((irq[i] < 2) || (irq[i] > 15) || (irq[i] == 6) ||
2417 (irq[i] == 8) || (irq[i] == 13))
2418 irq[i] = 0;
2419 else if (irq[i] == 2)
2420 irq[i] = 9;
2421 }
2422 }
2423
2424 if ((dma != 1) && (dma != 3))
2425 dma = 0;
2426
2427 if ((rx_trigger < 1) || (rx_trigger > 1023))
2428 rx_trigger = 768;
2429
2430 if ((tx_trigger < 1) || (tx_trigger > 1023))
2431 tx_trigger = 768;
2432
2433 if ((flow_off < 1) || (flow_off > 1023))
2434 flow_off = 1016;
2435
2436 if ((flow_on < 1) || (flow_on > 1023))
2437 flow_on = 944;
2438
2439 if ((rx_timeout < 0) || (rx_timeout > 255))
2440 rx_timeout = 128;
2441
2442 if (flow_on >= flow_off)
2443 flow_on = flow_off - 1;
2444
2445 show_serial_version();
2446
2447 /* Initialize the tty_driver structure */
2448
2449 esp_driver->owner = THIS_MODULE;
2450 esp_driver->name = "ttyP";
2451 esp_driver->major = ESP_IN_MAJOR;
2452 esp_driver->minor_start = 0;
2453 esp_driver->type = TTY_DRIVER_TYPE_SERIAL;
2454 esp_driver->subtype = SERIAL_TYPE_NORMAL;
2455 esp_driver->init_termios = tty_std_termios;
2456 esp_driver->init_termios.c_cflag =
2457 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
2458 esp_driver->flags = TTY_DRIVER_REAL_RAW;
2459 tty_set_operations(esp_driver, &esp_ops);
2460 if (tty_register_driver(esp_driver))
2461 {
2462 printk(KERN_ERR "Couldn't register esp serial driver");
2463 put_tty_driver(esp_driver);
2464 return 1;
2465 }
2466
2467 info = kmalloc(sizeof(struct esp_struct), GFP_KERNEL);
2468
2469 if (!info)
2470 {
2471 printk(KERN_ERR "Couldn't allocate memory for esp serial device information\n");
2472 tty_unregister_driver(esp_driver);
2473 put_tty_driver(esp_driver);
2474 return 1;
2475 }
2476
2477 memset((void *)info, 0, sizeof(struct esp_struct));
2478 spin_lock_init(&info->lock);
2479 /* rx_trigger, tx_trigger are needed by autoconfig */
2480 info->config.rx_trigger = rx_trigger;
2481 info->config.tx_trigger = tx_trigger;
2482
2483 i = 0;
2484 offset = 0;
2485
2486 do {
2487 info->port = esp[i] + offset;
2488 info->irq = irq[i];
2489 info->line = (i * 8) + (offset / 8);
2490
2491 if (!autoconfig(info)) {
2492 i++;
2493 offset = 0;
2494 continue;
2495 }
2496
2497 info->custom_divisor = (divisor[i] >> (offset / 2)) & 0xf;
2498 info->flags = STD_COM_FLAGS;
2499 if (info->custom_divisor)
2500 info->flags |= ASYNC_SPD_CUST;
2501 info->magic = ESP_MAGIC;
2502 info->close_delay = 5*HZ/10;
2503 info->closing_wait = 30*HZ;
2504 INIT_WORK(&info->tqueue, do_softint, info);
2505 INIT_WORK(&info->tqueue_hangup, do_serial_hangup, info);
2506 info->config.rx_timeout = rx_timeout;
2507 info->config.flow_on = flow_on;
2508 info->config.flow_off = flow_off;
2509 info->config.pio_threshold = pio_threshold;
2510 info->next_port = ports;
2511 init_waitqueue_head(&info->open_wait);
2512 init_waitqueue_head(&info->close_wait);
2513 init_waitqueue_head(&info->delta_msr_wait);
2514 init_waitqueue_head(&info->break_wait);
2515 ports = info;
2516 printk(KERN_INFO "ttyP%d at 0x%04x (irq = %d) is an ESP ",
2517 info->line, info->port, info->irq);
2518
2519 if (info->line % 8) {
2520 printk("secondary port\n");
2521 /* 8 port cards can't do DMA */
2522 info->stat_flags |= ESP_STAT_NEVER_DMA;
2523
2524 if (last_primary)
2525 last_primary->stat_flags |= ESP_STAT_NEVER_DMA;
2526 } else {
2527 printk("primary port\n");
2528 last_primary = info;
2529 irq[i] = info->irq;
2530 }
2531
2532 if (!dma)
2533 info->stat_flags |= ESP_STAT_NEVER_DMA;
2534
2535 info = kmalloc(sizeof(struct esp_struct), GFP_KERNEL);
2536 if (!info)
2537 {
2538 printk(KERN_ERR "Couldn't allocate memory for esp serial device information\n");
2539
2540 /* allow use of the already detected ports */
2541 return 0;
2542 }
2543
2544 memset((void *)info, 0, sizeof(struct esp_struct));
2545 /* rx_trigger, tx_trigger are needed by autoconfig */
2546 info->config.rx_trigger = rx_trigger;
2547 info->config.tx_trigger = tx_trigger;
2548
2549 if (offset == 56) {
2550 i++;
2551 offset = 0;
2552 } else {
2553 offset += 8;
2554 }
2555 } while (i < NR_PRIMARY);
2556
2557 /* free the last port memory allocation */
2558 kfree(info);
2559
2560 return 0;
2561 }
2562
2563 static void __exit espserial_exit(void)
2564 {
2565 int e1;
2566 struct esp_struct *temp_async;
2567 struct esp_pio_buffer *pio_buf;
2568
2569 /* printk("Unloading %s: version %s\n", serial_name, serial_version); */
2570 if ((e1 = tty_unregister_driver(esp_driver)))
2571 printk("SERIAL: failed to unregister serial driver (%d)\n",
2572 e1);
2573 put_tty_driver(esp_driver);
2574
2575 while (ports) {
2576 if (ports->port) {
2577 release_region(ports->port, REGION_SIZE);
2578 }
2579 temp_async = ports->next_port;
2580 kfree(ports);
2581 ports = temp_async;
2582 }
2583
2584 if (dma_buffer)
2585 free_pages((unsigned long)dma_buffer,
2586 get_order(DMA_BUFFER_SZ));
2587
2588 while (free_pio_buf) {
2589 pio_buf = free_pio_buf->next;
2590 kfree(free_pio_buf);
2591 free_pio_buf = pio_buf;
2592 }
2593 }
2594
2595 module_init(espserial_init);
2596 module_exit(espserial_exit);
kernel-based virtual machine