1 /* 68328serial.c: Serial port driver for 68328 microcontroller
2 *
3 * Copyright (C) 1995 David S. Miller <davem@caip.rutgers.edu>
4 * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
5 * Copyright (C) 1998, 1999 D. Jeff Dionne <jeff@uclinux.org>
6 * Copyright (C) 1999 Vladimir Gurevich <vgurevic@cisco.com>
7 * Copyright (C) 2002-2003 David McCullough <davidm@snapgear.com>
8 * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
9 *
10 * VZ Support/Fixes Evan Stawnyczy <e@lineo.ca>
11 * Multiple UART support Daniel Potts <danielp@cse.unsw.edu.au>
12 * Power management support Daniel Potts <danielp@cse.unsw.edu.au>
13 * VZ Second Serial Port enable Phil Wilshire
14 * 2.4/2.5 port David McCullough
15 */
16
17 #include <linux/module.h>
18 #include <linux/errno.h>
19 #include <linux/serial.h>
20 #include <linux/signal.h>
21 #include <linux/sched.h>
22 #include <linux/timer.h>
23 #include <linux/interrupt.h>
24 #include <linux/tty.h>
25 #include <linux/tty_flip.h>
26 #include <linux/major.h>
27 #include <linux/string.h>
28 #include <linux/fcntl.h>
29 #include <linux/mm.h>
30 #include <linux/kernel.h>
31 #include <linux/console.h>
32 #include <linux/reboot.h>
33 #include <linux/keyboard.h>
34 #include <linux/init.h>
35 #include <linux/pm.h>
36 #include <linux/bitops.h>
37 #include <linux/delay.h>
38 #include <linux/gfp.h>
39
40 #include <asm/io.h>
41 #include <asm/irq.h>
42 #include <asm/delay.h>
43 #include <asm/uaccess.h>
44
45 /* (es) */
46 /* note: perhaps we can murge these files, so that you can just
47 * define 1 of them, and they can sort that out for themselves
48 */
49 #if defined(CONFIG_M68EZ328)
50 #include <asm/MC68EZ328.h>
51 #else
52 #if defined(CONFIG_M68VZ328)
53 #include <asm/MC68VZ328.h>
54 #else
55 #include <asm/MC68328.h>
56 #endif /* CONFIG_M68VZ328 */
57 #endif /* CONFIG_M68EZ328 */
58
59 /* Turn off usage of real serial interrupt code, to "support" Copilot */
60 #ifdef CONFIG_XCOPILOT_BUGS
61 #undef USE_INTS
62 #else
63 #define USE_INTS
64 #endif
65
66 /*
67 * I believe this is the optimal setting that reduces the number of interrupts.
68 * At high speeds the output might become a little "bursted" (use USTCNT_TXHE
69 * if that bothers you), but in most cases it will not, since we try to
70 * transmit characters every time rs_interrupt is called. Thus, quite often
71 * you'll see that a receive interrupt occures before the transmit one.
72 * -- Vladimir Gurevich
73 */
74 #define USTCNT_TX_INTR_MASK (USTCNT_TXEE)
75
76 /*
77 * 68328 and 68EZ328 UARTS are a little bit different. EZ328 has special
78 * "Old data interrupt" which occures whenever the data stay in the FIFO
79 * longer than 30 bits time. This allows us to use FIFO without compromising
80 * latency. '328 does not have this feature and without the real 328-based
81 * board I would assume that RXRE is the safest setting.
82 *
83 * For EZ328 I use RXHE (Half empty) interrupt to reduce the number of
84 * interrupts. RXFE (receive queue full) causes the system to lose data
85 * at least at 115200 baud
86 *
87 * If your board is busy doing other stuff, you might consider to use
88 * RXRE (data ready intrrupt) instead.
89 *
90 * The other option is to make these INTR masks run-time configurable, so
91 * that people can dynamically adapt them according to the current usage.
92 * -- Vladimir Gurevich
93 */
94
95 /* (es) */
96 #if defined(CONFIG_M68EZ328) || defined(CONFIG_M68VZ328)
97 #define USTCNT_RX_INTR_MASK (USTCNT_RXHE | USTCNT_ODEN)
98 #elif defined(CONFIG_M68328)
99 #define USTCNT_RX_INTR_MASK (USTCNT_RXRE)
100 #else
101 #error Please, define the Rx interrupt events for your CPU
102 #endif
103 /* (/es) */
104
105 /*
106 * This is our internal structure for each serial port's state.
107 */
108 struct m68k_serial {
109 struct tty_port tport;
110 char is_cons; /* Is this our console. */
111 int magic;
112 int baud_base;
113 int port;
114 int irq;
115 int type; /* UART type */
116 int custom_divisor;
117 int x_char; /* xon/xoff character */
118 int line;
119 unsigned char *xmit_buf;
120 int xmit_head;
121 int xmit_tail;
122 int xmit_cnt;
123 };
124
125 #define SERIAL_MAGIC 0x5301
126
127 /*
128 * Define the number of ports supported and their irqs.
129 */
130 #define NR_PORTS 1
131
132 static struct m68k_serial m68k_soft[NR_PORTS];
133
134 static unsigned int uart_irqs[NR_PORTS] = { UART_IRQ_NUM };
135
136 /* multiple ports are contiguous in memory */
137 m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR;
138
139 struct tty_driver *serial_driver;
140
141 static void change_speed(struct m68k_serial *info, struct tty_struct *tty);
142
143 /*
144 * Setup for console. Argument comes from the boot command line.
145 */
146
147 /* note: this is messy, but it works, again, perhaps defined somewhere else?*/
148 #ifdef CONFIG_M68VZ328
149 #define CONSOLE_BAUD_RATE 19200
150 #define DEFAULT_CBAUD B19200
151 #endif
152
153
154 #ifndef CONSOLE_BAUD_RATE
155 #define CONSOLE_BAUD_RATE 9600
156 #define DEFAULT_CBAUD B9600
157 #endif
158
159
160 static int m68328_console_initted = 0;
161 static int m68328_console_baud = CONSOLE_BAUD_RATE;
162 static int m68328_console_cbaud = DEFAULT_CBAUD;
163
164
serial_paranoia_check(struct m68k_serial * info,char * name,const char * routine)165 static inline int serial_paranoia_check(struct m68k_serial *info,
166 char *name, const char *routine)
167 {
168 #ifdef SERIAL_PARANOIA_CHECK
169 static const char *badmagic =
170 "Warning: bad magic number for serial struct %s in %s\n";
171 static const char *badinfo =
172 "Warning: null m68k_serial for %s in %s\n";
173
174 if (!info) {
175 printk(badinfo, name, routine);
176 return 1;
177 }
178 if (info->magic != SERIAL_MAGIC) {
179 printk(badmagic, name, routine);
180 return 1;
181 }
182 #endif
183 return 0;
184 }
185
186 /*
187 * This is used to figure out the divisor speeds and the timeouts
188 */
189 static int baud_table[] = {
190 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
191 9600, 19200, 38400, 57600, 115200, 0 };
192
193 /* Utility routines */
get_baud(struct m68k_serial * ss)194 static inline int get_baud(struct m68k_serial *ss)
195 {
196 unsigned long result = 115200;
197 unsigned short int baud = uart_addr[ss->line].ubaud;
198 if (GET_FIELD(baud, UBAUD_PRESCALER) == 0x38) result = 38400;
199 result >>= GET_FIELD(baud, UBAUD_DIVIDE);
200
201 return result;
202 }
203
204 /*
205 * ------------------------------------------------------------
206 * rs_stop() and rs_start()
207 *
208 * This routines are called before setting or resetting tty->stopped.
209 * They enable or disable transmitter interrupts, as necessary.
210 * ------------------------------------------------------------
211 */
rs_stop(struct tty_struct * tty)212 static void rs_stop(struct tty_struct *tty)
213 {
214 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
215 m68328_uart *uart = &uart_addr[info->line];
216 unsigned long flags;
217
218 if (serial_paranoia_check(info, tty->name, "rs_stop"))
219 return;
220
221 local_irq_save(flags);
222 uart->ustcnt &= ~USTCNT_TXEN;
223 local_irq_restore(flags);
224 }
225
rs_put_char(char ch)226 static int rs_put_char(char ch)
227 {
228 unsigned long flags;
229 int loops = 0;
230
231 local_irq_save(flags);
232
233 while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) {
234 loops++;
235 udelay(5);
236 }
237
238 UTX_TXDATA = ch;
239 udelay(5);
240 local_irq_restore(flags);
241 return 1;
242 }
243
rs_start(struct tty_struct * tty)244 static void rs_start(struct tty_struct *tty)
245 {
246 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
247 m68328_uart *uart = &uart_addr[info->line];
248 unsigned long flags;
249
250 if (serial_paranoia_check(info, tty->name, "rs_start"))
251 return;
252
253 local_irq_save(flags);
254 if (info->xmit_cnt && info->xmit_buf && !(uart->ustcnt & USTCNT_TXEN)) {
255 #ifdef USE_INTS
256 uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
257 #else
258 uart->ustcnt |= USTCNT_TXEN;
259 #endif
260 }
261 local_irq_restore(flags);
262 }
263
receive_chars(struct m68k_serial * info,unsigned short rx)264 static void receive_chars(struct m68k_serial *info, unsigned short rx)
265 {
266 m68328_uart *uart = &uart_addr[info->line];
267 unsigned char ch, flag;
268
269 /*
270 * This do { } while() loop will get ALL chars out of Rx FIFO
271 */
272 #ifndef CONFIG_XCOPILOT_BUGS
273 do {
274 #endif
275 ch = GET_FIELD(rx, URX_RXDATA);
276
277 if(info->is_cons) {
278 if(URX_BREAK & rx) { /* whee, break received */
279 return;
280 #ifdef CONFIG_MAGIC_SYSRQ
281 } else if (ch == 0x10) { /* ^P */
282 show_state();
283 show_free_areas(0);
284 show_buffers();
285 /* show_net_buffers(); */
286 return;
287 } else if (ch == 0x12) { /* ^R */
288 emergency_restart();
289 return;
290 #endif /* CONFIG_MAGIC_SYSRQ */
291 }
292 }
293
294 flag = TTY_NORMAL;
295
296 if (rx & URX_PARITY_ERROR)
297 flag = TTY_PARITY;
298 else if (rx & URX_OVRUN)
299 flag = TTY_OVERRUN;
300 else if (rx & URX_FRAME_ERROR)
301 flag = TTY_FRAME;
302
303 tty_insert_flip_char(&info->tport, ch, flag);
304 #ifndef CONFIG_XCOPILOT_BUGS
305 } while((rx = uart->urx.w) & URX_DATA_READY);
306 #endif
307
308 tty_schedule_flip(&info->tport);
309 }
310
transmit_chars(struct m68k_serial * info,struct tty_struct * tty)311 static void transmit_chars(struct m68k_serial *info, struct tty_struct *tty)
312 {
313 m68328_uart *uart = &uart_addr[info->line];
314
315 if (info->x_char) {
316 /* Send next char */
317 uart->utx.b.txdata = info->x_char;
318 info->x_char = 0;
319 goto clear_and_return;
320 }
321
322 if ((info->xmit_cnt <= 0) || !tty || tty->stopped) {
323 /* That's peculiar... TX ints off */
324 uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
325 goto clear_and_return;
326 }
327
328 /* Send char */
329 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
330 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
331 info->xmit_cnt--;
332
333 if(info->xmit_cnt <= 0) {
334 /* All done for now... TX ints off */
335 uart->ustcnt &= ~USTCNT_TX_INTR_MASK;
336 goto clear_and_return;
337 }
338
339 clear_and_return:
340 /* Clear interrupt (should be auto)*/
341 return;
342 }
343
344 /*
345 * This is the serial driver's generic interrupt routine
346 */
rs_interrupt(int irq,void * dev_id)347 irqreturn_t rs_interrupt(int irq, void *dev_id)
348 {
349 struct m68k_serial *info = dev_id;
350 struct tty_struct *tty = tty_port_tty_get(&info->tport);
351 m68328_uart *uart;
352 unsigned short rx;
353 unsigned short tx;
354
355 uart = &uart_addr[info->line];
356 rx = uart->urx.w;
357
358 #ifdef USE_INTS
359 tx = uart->utx.w;
360
361 if (rx & URX_DATA_READY)
362 receive_chars(info, rx);
363 if (tx & UTX_TX_AVAIL)
364 transmit_chars(info, tty);
365 #else
366 receive_chars(info, rx);
367 #endif
368 tty_kref_put(tty);
369
370 return IRQ_HANDLED;
371 }
372
startup(struct m68k_serial * info,struct tty_struct * tty)373 static int startup(struct m68k_serial *info, struct tty_struct *tty)
374 {
375 m68328_uart *uart = &uart_addr[info->line];
376 unsigned long flags;
377
378 if (info->tport.flags & ASYNC_INITIALIZED)
379 return 0;
380
381 if (!info->xmit_buf) {
382 info->xmit_buf = (unsigned char *) __get_free_page(GFP_KERNEL);
383 if (!info->xmit_buf)
384 return -ENOMEM;
385 }
386
387 local_irq_save(flags);
388
389 /*
390 * Clear the FIFO buffers and disable them
391 * (they will be reenabled in change_speed())
392 */
393
394 uart->ustcnt = USTCNT_UEN;
395 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_TXEN;
396 (void)uart->urx.w;
397
398 /*
399 * Finally, enable sequencing and interrupts
400 */
401 #ifdef USE_INTS
402 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN |
403 USTCNT_RX_INTR_MASK | USTCNT_TX_INTR_MASK;
404 #else
405 uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_RX_INTR_MASK;
406 #endif
407
408 if (tty)
409 clear_bit(TTY_IO_ERROR, &tty->flags);
410 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
411
412 /*
413 * and set the speed of the serial port
414 */
415
416 change_speed(info, tty);
417
418 info->tport.flags |= ASYNC_INITIALIZED;
419 local_irq_restore(flags);
420 return 0;
421 }
422
423 /*
424 * This routine will shutdown a serial port; interrupts are disabled, and
425 * DTR is dropped if the hangup on close termio flag is on.
426 */
shutdown(struct m68k_serial * info,struct tty_struct * tty)427 static void shutdown(struct m68k_serial *info, struct tty_struct *tty)
428 {
429 m68328_uart *uart = &uart_addr[info->line];
430 unsigned long flags;
431
432 uart->ustcnt = 0; /* All off! */
433 if (!(info->tport.flags & ASYNC_INITIALIZED))
434 return;
435
436 local_irq_save(flags);
437
438 if (info->xmit_buf) {
439 free_page((unsigned long) info->xmit_buf);
440 info->xmit_buf = 0;
441 }
442
443 if (tty)
444 set_bit(TTY_IO_ERROR, &tty->flags);
445
446 info->tport.flags &= ~ASYNC_INITIALIZED;
447 local_irq_restore(flags);
448 }
449
450 struct {
451 int divisor, prescale;
452 }
453 #ifndef CONFIG_M68VZ328
454 hw_baud_table[18] = {
455 {0,0}, /* 0 */
456 {0,0}, /* 50 */
457 {0,0}, /* 75 */
458 {0,0}, /* 110 */
459 {0,0}, /* 134 */
460 {0,0}, /* 150 */
461 {0,0}, /* 200 */
462 {7,0x26}, /* 300 */
463 {6,0x26}, /* 600 */
464 {5,0x26}, /* 1200 */
465 {0,0}, /* 1800 */
466 {4,0x26}, /* 2400 */
467 {3,0x26}, /* 4800 */
468 {2,0x26}, /* 9600 */
469 {1,0x26}, /* 19200 */
470 {0,0x26}, /* 38400 */
471 {1,0x38}, /* 57600 */
472 {0,0x38}, /* 115200 */
473 };
474 #else
475 hw_baud_table[18] = {
476 {0,0}, /* 0 */
477 {0,0}, /* 50 */
478 {0,0}, /* 75 */
479 {0,0}, /* 110 */
480 {0,0}, /* 134 */
481 {0,0}, /* 150 */
482 {0,0}, /* 200 */
483 {0,0}, /* 300 */
484 {7,0x26}, /* 600 */
485 {6,0x26}, /* 1200 */
486 {0,0}, /* 1800 */
487 {5,0x26}, /* 2400 */
488 {4,0x26}, /* 4800 */
489 {3,0x26}, /* 9600 */
490 {2,0x26}, /* 19200 */
491 {1,0x26}, /* 38400 */
492 {0,0x26}, /* 57600 */
493 {1,0x38}, /* 115200 */
494 };
495 #endif
496 /* rate = 1036800 / ((65 - prescale) * (1<<divider)) */
497
498 /*
499 * This routine is called to set the UART divisor registers to match
500 * the specified baud rate for a serial port.
501 */
change_speed(struct m68k_serial * info,struct tty_struct * tty)502 static void change_speed(struct m68k_serial *info, struct tty_struct *tty)
503 {
504 m68328_uart *uart = &uart_addr[info->line];
505 unsigned short port;
506 unsigned short ustcnt;
507 unsigned cflag;
508 int i;
509
510 cflag = tty->termios.c_cflag;
511 if (!(port = info->port))
512 return;
513
514 ustcnt = uart->ustcnt;
515 uart->ustcnt = ustcnt & ~USTCNT_TXEN;
516
517 i = cflag & CBAUD;
518 if (i & CBAUDEX) {
519 i = (i & ~CBAUDEX) + B38400;
520 }
521
522 uart->ubaud = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
523 PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
524
525 ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
526
527 if ((cflag & CSIZE) == CS8)
528 ustcnt |= USTCNT_8_7;
529
530 if (cflag & CSTOPB)
531 ustcnt |= USTCNT_STOP;
532
533 if (cflag & PARENB)
534 ustcnt |= USTCNT_PARITYEN;
535 if (cflag & PARODD)
536 ustcnt |= USTCNT_ODD_EVEN;
537
538 #ifdef CONFIG_SERIAL_68328_RTS_CTS
539 if (cflag & CRTSCTS) {
540 uart->utx.w &= ~ UTX_NOCTS;
541 } else {
542 uart->utx.w |= UTX_NOCTS;
543 }
544 #endif
545
546 ustcnt |= USTCNT_TXEN;
547
548 uart->ustcnt = ustcnt;
549 return;
550 }
551
552 /*
553 * Fair output driver allows a process to speak.
554 */
rs_fair_output(void)555 static void rs_fair_output(void)
556 {
557 int left; /* Output no more than that */
558 unsigned long flags;
559 struct m68k_serial *info = &m68k_soft[0];
560 char c;
561
562 if (info == 0) return;
563 if (info->xmit_buf == 0) return;
564
565 local_irq_save(flags);
566 left = info->xmit_cnt;
567 while (left != 0) {
568 c = info->xmit_buf[info->xmit_tail];
569 info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1);
570 info->xmit_cnt--;
571 local_irq_restore(flags);
572
573 rs_put_char(c);
574
575 local_irq_save(flags);
576 left = min(info->xmit_cnt, left-1);
577 }
578
579 /* Last character is being transmitted now (hopefully). */
580 udelay(5);
581
582 local_irq_restore(flags);
583 return;
584 }
585
586 /*
587 * m68k_console_print is registered for printk.
588 */
console_print_68328(const char * p)589 void console_print_68328(const char *p)
590 {
591 char c;
592
593 while((c=*(p++)) != 0) {
594 if(c == '\n')
595 rs_put_char('\r');
596 rs_put_char(c);
597 }
598
599 /* Comment this if you want to have a strict interrupt-driven output */
600 rs_fair_output();
601
602 return;
603 }
604
rs_set_ldisc(struct tty_struct * tty)605 static void rs_set_ldisc(struct tty_struct *tty)
606 {
607 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
608
609 if (serial_paranoia_check(info, tty->name, "rs_set_ldisc"))
610 return;
611
612 info->is_cons = (tty->termios.c_line == N_TTY);
613
614 printk("ttyS%d console mode %s\n", info->line, info->is_cons ? "on" : "off");
615 }
616
rs_flush_chars(struct tty_struct * tty)617 static void rs_flush_chars(struct tty_struct *tty)
618 {
619 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
620 m68328_uart *uart = &uart_addr[info->line];
621 unsigned long flags;
622
623 if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
624 return;
625 #ifndef USE_INTS
626 for(;;) {
627 #endif
628
629 /* Enable transmitter */
630 local_irq_save(flags);
631
632 if (info->xmit_cnt <= 0 || tty->stopped || !info->xmit_buf) {
633 local_irq_restore(flags);
634 return;
635 }
636
637 #ifdef USE_INTS
638 uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK;
639 #else
640 uart->ustcnt |= USTCNT_TXEN;
641 #endif
642
643 #ifdef USE_INTS
644 if (uart->utx.w & UTX_TX_AVAIL) {
645 #else
646 if (1) {
647 #endif
648 /* Send char */
649 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
650 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
651 info->xmit_cnt--;
652 }
653
654 #ifndef USE_INTS
655 while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
656 }
657 #endif
658 local_irq_restore(flags);
659 }
660
661 extern void console_printn(const char * b, int count);
662
663 static int rs_write(struct tty_struct * tty,
664 const unsigned char *buf, int count)
665 {
666 int c, total = 0;
667 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
668 m68328_uart *uart = &uart_addr[info->line];
669 unsigned long flags;
670
671 if (serial_paranoia_check(info, tty->name, "rs_write"))
672 return 0;
673
674 if (!tty || !info->xmit_buf)
675 return 0;
676
677 local_save_flags(flags);
678 while (1) {
679 local_irq_disable();
680 c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
681 SERIAL_XMIT_SIZE - info->xmit_head));
682 local_irq_restore(flags);
683
684 if (c <= 0)
685 break;
686
687 memcpy(info->xmit_buf + info->xmit_head, buf, c);
688
689 local_irq_disable();
690 info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
691 info->xmit_cnt += c;
692 local_irq_restore(flags);
693 buf += c;
694 count -= c;
695 total += c;
696 }
697
698 if (info->xmit_cnt && !tty->stopped) {
699 /* Enable transmitter */
700 local_irq_disable();
701 #ifndef USE_INTS
702 while(info->xmit_cnt) {
703 #endif
704
705 uart->ustcnt |= USTCNT_TXEN;
706 #ifdef USE_INTS
707 uart->ustcnt |= USTCNT_TX_INTR_MASK;
708 #else
709 while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5);
710 #endif
711 if (uart->utx.w & UTX_TX_AVAIL) {
712 uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++];
713 info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
714 info->xmit_cnt--;
715 }
716
717 #ifndef USE_INTS
718 }
719 #endif
720 local_irq_restore(flags);
721 }
722
723 return total;
724 }
725
726 static int rs_write_room(struct tty_struct *tty)
727 {
728 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
729 int ret;
730
731 if (serial_paranoia_check(info, tty->name, "rs_write_room"))
732 return 0;
733 ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
734 if (ret < 0)
735 ret = 0;
736 return ret;
737 }
738
739 static int rs_chars_in_buffer(struct tty_struct *tty)
740 {
741 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
742
743 if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
744 return 0;
745 return info->xmit_cnt;
746 }
747
748 static void rs_flush_buffer(struct tty_struct *tty)
749 {
750 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
751 unsigned long flags;
752
753 if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
754 return;
755 local_irq_save(flags);
756 info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
757 local_irq_restore(flags);
758 tty_wakeup(tty);
759 }
760
761 /*
762 * ------------------------------------------------------------
763 * rs_throttle()
764 *
765 * This routine is called by the upper-layer tty layer to signal that
766 * incoming characters should be throttled.
767 * ------------------------------------------------------------
768 */
769 static void rs_throttle(struct tty_struct * tty)
770 {
771 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
772
773 if (serial_paranoia_check(info, tty->name, "rs_throttle"))
774 return;
775
776 if (I_IXOFF(tty))
777 info->x_char = STOP_CHAR(tty);
778
779 /* Turn off RTS line (do this atomic) */
780 }
781
782 static void rs_unthrottle(struct tty_struct * tty)
783 {
784 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
785
786 if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
787 return;
788
789 if (I_IXOFF(tty)) {
790 if (info->x_char)
791 info->x_char = 0;
792 else
793 info->x_char = START_CHAR(tty);
794 }
795
796 /* Assert RTS line (do this atomic) */
797 }
798
799 /*
800 * ------------------------------------------------------------
801 * rs_ioctl() and friends
802 * ------------------------------------------------------------
803 */
804
805 static int get_serial_info(struct m68k_serial * info,
806 struct serial_struct * retinfo)
807 {
808 struct serial_struct tmp;
809
810 if (!retinfo)
811 return -EFAULT;
812 memset(&tmp, 0, sizeof(tmp));
813 tmp.type = info->type;
814 tmp.line = info->line;
815 tmp.port = info->port;
816 tmp.irq = info->irq;
817 tmp.flags = info->tport.flags;
818 tmp.baud_base = info->baud_base;
819 tmp.close_delay = info->tport.close_delay;
820 tmp.closing_wait = info->tport.closing_wait;
821 tmp.custom_divisor = info->custom_divisor;
822 if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
823 return -EFAULT;
824
825 return 0;
826 }
827
828 static int set_serial_info(struct m68k_serial *info, struct tty_struct *tty,
829 struct serial_struct * new_info)
830 {
831 struct tty_port *port = &info->tport;
832 struct serial_struct new_serial;
833 struct m68k_serial old_info;
834 int retval = 0;
835
836 if (!new_info)
837 return -EFAULT;
838 if (copy_from_user(&new_serial, new_info, sizeof(new_serial)))
839 return -EFAULT;
840 old_info = *info;
841
842 if (!capable(CAP_SYS_ADMIN)) {
843 if ((new_serial.baud_base != info->baud_base) ||
844 (new_serial.type != info->type) ||
845 (new_serial.close_delay != port->close_delay) ||
846 ((new_serial.flags & ~ASYNC_USR_MASK) !=
847 (port->flags & ~ASYNC_USR_MASK)))
848 return -EPERM;
849 port->flags = ((port->flags & ~ASYNC_USR_MASK) |
850 (new_serial.flags & ASYNC_USR_MASK));
851 info->custom_divisor = new_serial.custom_divisor;
852 goto check_and_exit;
853 }
854
855 if (port->count > 1)
856 return -EBUSY;
857
858 /*
859 * OK, past this point, all the error checking has been done.
860 * At this point, we start making changes.....
861 */
862
863 info->baud_base = new_serial.baud_base;
864 port->flags = ((port->flags & ~ASYNC_FLAGS) |
865 (new_serial.flags & ASYNC_FLAGS));
866 info->type = new_serial.type;
867 port->close_delay = new_serial.close_delay;
868 port->closing_wait = new_serial.closing_wait;
869
870 check_and_exit:
871 retval = startup(info, tty);
872 return retval;
873 }
874
875 /*
876 * get_lsr_info - get line status register info
877 *
878 * Purpose: Let user call ioctl() to get info when the UART physically
879 * is emptied. On bus types like RS485, the transmitter must
880 * release the bus after transmitting. This must be done when
881 * the transmit shift register is empty, not be done when the
882 * transmit holding register is empty. This functionality
883 * allows an RS485 driver to be written in user space.
884 */
885 static int get_lsr_info(struct m68k_serial * info, unsigned int *value)
886 {
887 #ifdef CONFIG_SERIAL_68328_RTS_CTS
888 m68328_uart *uart = &uart_addr[info->line];
889 #endif
890 unsigned char status;
891 unsigned long flags;
892
893 local_irq_save(flags);
894 #ifdef CONFIG_SERIAL_68328_RTS_CTS
895 status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0;
896 #else
897 status = 0;
898 #endif
899 local_irq_restore(flags);
900 return put_user(status, value);
901 }
902
903 /*
904 * This routine sends a break character out the serial port.
905 */
906 static void send_break(struct m68k_serial * info, unsigned int duration)
907 {
908 m68328_uart *uart = &uart_addr[info->line];
909 unsigned long flags;
910 if (!info->port)
911 return;
912 local_irq_save(flags);
913 #ifdef USE_INTS
914 uart->utx.w |= UTX_SEND_BREAK;
915 msleep_interruptible(duration);
916 uart->utx.w &= ~UTX_SEND_BREAK;
917 #endif
918 local_irq_restore(flags);
919 }
920
921 static int rs_ioctl(struct tty_struct *tty,
922 unsigned int cmd, unsigned long arg)
923 {
924 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
925 int retval;
926
927 if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
928 return -ENODEV;
929
930 if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
931 (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
932 (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
933 if (tty->flags & (1 << TTY_IO_ERROR))
934 return -EIO;
935 }
936
937 switch (cmd) {
938 case TCSBRK: /* SVID version: non-zero arg --> no break */
939 retval = tty_check_change(tty);
940 if (retval)
941 return retval;
942 tty_wait_until_sent(tty, 0);
943 if (!arg)
944 send_break(info, 250); /* 1/4 second */
945 return 0;
946 case TCSBRKP: /* support for POSIX tcsendbreak() */
947 retval = tty_check_change(tty);
948 if (retval)
949 return retval;
950 tty_wait_until_sent(tty, 0);
951 send_break(info, arg ? arg*(100) : 250);
952 return 0;
953 case TIOCGSERIAL:
954 return get_serial_info(info,
955 (struct serial_struct *) arg);
956 case TIOCSSERIAL:
957 return set_serial_info(info, tty,
958 (struct serial_struct *) arg);
959 case TIOCSERGETLSR: /* Get line status register */
960 return get_lsr_info(info, (unsigned int *) arg);
961 case TIOCSERGSTRUCT:
962 if (copy_to_user((struct m68k_serial *) arg,
963 info, sizeof(struct m68k_serial)))
964 return -EFAULT;
965 return 0;
966 default:
967 return -ENOIOCTLCMD;
968 }
969 return 0;
970 }
971
972 static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
973 {
974 struct m68k_serial *info = (struct m68k_serial *)tty->driver_data;
975
976 change_speed(info, tty);
977
978 if ((old_termios->c_cflag & CRTSCTS) &&
979 !(tty->termios.c_cflag & CRTSCTS))
980 rs_start(tty);
981
982 }
983
984 /*
985 * ------------------------------------------------------------
986 * rs_close()
987 *
988 * This routine is called when the serial port gets closed. First, we
989 * wait for the last remaining data to be sent. Then, we unlink its
990 * S structure from the interrupt chain if necessary, and we free
991 * that IRQ if nothing is left in the chain.
992 * ------------------------------------------------------------
993 */
994 static void rs_close(struct tty_struct *tty, struct file * filp)
995 {
996 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
997 struct tty_port *port = &info->tport;
998 m68328_uart *uart = &uart_addr[info->line];
999 unsigned long flags;
1000
1001 if (serial_paranoia_check(info, tty->name, "rs_close"))
1002 return;
1003
1004 local_irq_save(flags);
1005
1006 if (tty_hung_up_p(filp)) {
1007 local_irq_restore(flags);
1008 return;
1009 }
1010
1011 if ((tty->count == 1) && (port->count != 1)) {
1012 /*
1013 * Uh, oh. tty->count is 1, which means that the tty
1014 * structure will be freed. Info->count should always
1015 * be one in these conditions. If it's greater than
1016 * one, we've got real problems, since it means the
1017 * serial port won't be shutdown.
1018 */
1019 printk("rs_close: bad serial port count; tty->count is 1, "
1020 "port->count is %d\n", port->count);
1021 port->count = 1;
1022 }
1023 if (--port->count < 0) {
1024 printk("rs_close: bad serial port count for ttyS%d: %d\n",
1025 info->line, port->count);
1026 port->count = 0;
1027 }
1028 if (port->count) {
1029 local_irq_restore(flags);
1030 return;
1031 }
1032 port->flags |= ASYNC_CLOSING;
1033 /*
1034 * Now we wait for the transmit buffer to clear; and we notify
1035 * the line discipline to only process XON/XOFF characters.
1036 */
1037 tty->closing = 1;
1038 if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
1039 tty_wait_until_sent(tty, port->closing_wait);
1040 /*
1041 * At this point we stop accepting input. To do this, we
1042 * disable the receive line status interrupts, and tell the
1043 * interrupt driver to stop checking the data ready bit in the
1044 * line status register.
1045 */
1046
1047 uart->ustcnt &= ~USTCNT_RXEN;
1048 uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK);
1049
1050 shutdown(info, tty);
1051 rs_flush_buffer(tty);
1052
1053 tty_ldisc_flush(tty);
1054 tty->closing = 0;
1055 tty_port_tty_set(&info->tport, NULL);
1056 #warning "This is not and has never been valid so fix it"
1057 #if 0
1058 if (tty->ldisc.num != ldiscs[N_TTY].num) {
1059 if (tty->ldisc.close)
1060 (tty->ldisc.close)(tty);
1061 tty->ldisc = ldiscs[N_TTY];
1062 tty->termios.c_line = N_TTY;
1063 if (tty->ldisc.open)
1064 (tty->ldisc.open)(tty);
1065 }
1066 #endif
1067 if (port->blocked_open) {
1068 if (port->close_delay)
1069 msleep_interruptible(jiffies_to_msecs(port->close_delay));
1070 wake_up_interruptible(&port->open_wait);
1071 }
1072 port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
1073 wake_up_interruptible(&port->close_wait);
1074 local_irq_restore(flags);
1075 }
1076
1077 /*
1078 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
1079 */
1080 void rs_hangup(struct tty_struct *tty)
1081 {
1082 struct m68k_serial * info = (struct m68k_serial *)tty->driver_data;
1083
1084 if (serial_paranoia_check(info, tty->name, "rs_hangup"))
1085 return;
1086
1087 rs_flush_buffer(tty);
1088 shutdown(info, tty);
1089 info->tport.count = 0;
1090 info->tport.flags &= ~ASYNC_NORMAL_ACTIVE;
1091 tty_port_tty_set(&info->tport, NULL);
1092 wake_up_interruptible(&info->tport.open_wait);
1093 }
1094
1095 /*
1096 * This routine is called whenever a serial port is opened. It
1097 * enables interrupts for a serial port, linking in its S structure into
1098 * the IRQ chain. It also performs the serial-specific
1099 * initialization for the tty structure.
1100 */
1101 int rs_open(struct tty_struct *tty, struct file * filp)
1102 {
1103 struct m68k_serial *info;
1104 int retval;
1105
1106 info = &m68k_soft[tty->index];
1107
1108 if (serial_paranoia_check(info, tty->name, "rs_open"))
1109 return -ENODEV;
1110
1111 info->tport.count++;
1112 tty->driver_data = info;
1113 tty_port_tty_set(&info->tport, tty);
1114
1115 /*
1116 * Start up serial port
1117 */
1118 retval = startup(info, tty);
1119 if (retval)
1120 return retval;
1121
1122 return tty_port_block_til_ready(&info->tport, tty, filp);
1123 }
1124
1125 /* Finally, routines used to initialize the serial driver. */
1126
1127 static void show_serial_version(void)
1128 {
1129 printk("MC68328 serial driver version 1.00\n");
1130 }
1131
1132 static const struct tty_operations rs_ops = {
1133 .open = rs_open,
1134 .close = rs_close,
1135 .write = rs_write,
1136 .flush_chars = rs_flush_chars,
1137 .write_room = rs_write_room,
1138 .chars_in_buffer = rs_chars_in_buffer,
1139 .flush_buffer = rs_flush_buffer,
1140 .ioctl = rs_ioctl,
1141 .throttle = rs_throttle,
1142 .unthrottle = rs_unthrottle,
1143 .set_termios = rs_set_termios,
1144 .stop = rs_stop,
1145 .start = rs_start,
1146 .hangup = rs_hangup,
1147 .set_ldisc = rs_set_ldisc,
1148 };
1149
1150 static const struct tty_port_operations rs_port_ops = {
1151 };
1152
1153 /* rs_init inits the driver */
1154 static int __init
1155 rs68328_init(void)
1156 {
1157 unsigned long flags;
1158 int i;
1159 struct m68k_serial *info;
1160
1161 serial_driver = alloc_tty_driver(NR_PORTS);
1162 if (!serial_driver)
1163 return -ENOMEM;
1164
1165 show_serial_version();
1166
1167 /* Initialize the tty_driver structure */
1168 /* SPARC: Not all of this is exactly right for us. */
1169
1170 serial_driver->name = "ttyS";
1171 serial_driver->major = TTY_MAJOR;
1172 serial_driver->minor_start = 64;
1173 serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
1174 serial_driver->subtype = SERIAL_TYPE_NORMAL;
1175 serial_driver->init_termios = tty_std_termios;
1176 serial_driver->init_termios.c_cflag =
1177 m68328_console_cbaud | CS8 | CREAD | HUPCL | CLOCAL;
1178 serial_driver->flags = TTY_DRIVER_REAL_RAW;
1179 tty_set_operations(serial_driver, &rs_ops);
1180
1181 local_irq_save(flags);
1182
1183 for(i=0;i<NR_PORTS;i++) {
1184
1185 info = &m68k_soft[i];
1186 tty_port_init(&info->tport);
1187 info->tport.ops = &rs_port_ops;
1188 info->magic = SERIAL_MAGIC;
1189 info->port = (int) &uart_addr[i];
1190 info->irq = uart_irqs[i];
1191 info->custom_divisor = 16;
1192 info->x_char = 0;
1193 info->line = i;
1194 info->is_cons = 1; /* Means shortcuts work */
1195
1196 printk("%s%d at 0x%08x (irq = %d)", serial_driver->name, info->line,
1197 info->port, info->irq);
1198 printk(" is a builtin MC68328 UART\n");
1199
1200 #ifdef CONFIG_M68VZ328
1201 if (i > 0 )
1202 PJSEL &= 0xCF; /* PSW enable second port output */
1203 #endif
1204
1205 if (request_irq(uart_irqs[i],
1206 rs_interrupt,
1207 0,
1208 "M68328_UART", info))
1209 panic("Unable to attach 68328 serial interrupt\n");
1210
1211 tty_port_link_device(&info->tport, serial_driver, i);
1212 }
1213 local_irq_restore(flags);
1214
1215 if (tty_register_driver(serial_driver)) {
1216 put_tty_driver(serial_driver);
1217 for (i = 0; i < NR_PORTS; i++)
1218 tty_port_destroy(&m68k_soft[i].tport);
1219 printk(KERN_ERR "Couldn't register serial driver\n");
1220 return -ENOMEM;
1221 }
1222
1223 return 0;
1224 }
1225
1226 module_init(rs68328_init);
1227
1228
1229
1230 static void m68328_set_baud(void)
1231 {
1232 unsigned short ustcnt;
1233 int i;
1234
1235 ustcnt = USTCNT;
1236 USTCNT = ustcnt & ~USTCNT_TXEN;
1237
1238 again:
1239 for (i = 0; i < ARRAY_SIZE(baud_table); i++)
1240 if (baud_table[i] == m68328_console_baud)
1241 break;
1242 if (i >= ARRAY_SIZE(baud_table)) {
1243 m68328_console_baud = 9600;
1244 goto again;
1245 }
1246
1247 UBAUD = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) |
1248 PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale);
1249 ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7);
1250 ustcnt |= USTCNT_8_7;
1251 ustcnt |= USTCNT_TXEN;
1252 USTCNT = ustcnt;
1253 m68328_console_initted = 1;
1254 return;
1255 }
1256
1257
1258 int m68328_console_setup(struct console *cp, char *arg)
1259 {
1260 int i, n = CONSOLE_BAUD_RATE;
1261
1262 if (!cp)
1263 return(-1);
1264
1265 if (arg)
1266 n = simple_strtoul(arg,NULL,0);
1267
1268 for (i = 0; i < ARRAY_SIZE(baud_table); i++)
1269 if (baud_table[i] == n)
1270 break;
1271 if (i < ARRAY_SIZE(baud_table)) {
1272 m68328_console_baud = n;
1273 m68328_console_cbaud = 0;
1274 if (i > 15) {
1275 m68328_console_cbaud |= CBAUDEX;
1276 i -= 15;
1277 }
1278 m68328_console_cbaud |= i;
1279 }
1280
1281 m68328_set_baud(); /* make sure baud rate changes */
1282 return(0);
1283 }
1284
1285
1286 static struct tty_driver *m68328_console_device(struct console *c, int *index)
1287 {
1288 *index = c->index;
1289 return serial_driver;
1290 }
1291
1292
1293 void m68328_console_write (struct console *co, const char *str,
1294 unsigned int count)
1295 {
1296 if (!m68328_console_initted)
1297 m68328_set_baud();
1298 while (count--) {
1299 if (*str == '\n')
1300 rs_put_char('\r');
1301 rs_put_char( *str++ );
1302 }
1303 }
1304
1305
1306 static struct console m68328_driver = {
1307 .name = "ttyS",
1308 .write = m68328_console_write,
1309 .device = m68328_console_device,
1310 .setup = m68328_console_setup,
1311 .flags = CON_PRINTBUFFER,
1312 .index = -1,
1313 };
1314
1315
1316 static int __init m68328_console_init(void)
1317 {
1318 register_console(&m68328_driver);
1319 return 0;
1320 }
1321
1322 console_initcall(m68328_console_init);
1323