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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Driver for 8250/16550-type serial ports
3 *
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5 *
6 * Copyright (C) 2001 Russell King.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * A note about mapbase / membase
14 *
15 * mapbase is the physical address of the IO port. Currently, we don't
16 * support this very well, and it may well be dropped from this driver
17 * in future. As such, mapbase should be NULL.
18 *
19 * membase is an 'ioremapped' cookie. This is compatible with the old
20 * serial.c driver, and is currently the preferred form.
21 */
22#include <linux/config.h>
23#include <linux/module.h>
24#include <linux/tty.h>
25#include <linux/ioport.h>
26#include <linux/init.h>
27#include <linux/console.h>
28#include <linux/sysrq.h>
29#include <linux/serial.h>
30#include <linux/serialP.h>
31#include <linux/delay.h>
32
33#include <asm/serial.h>
34#include <asm/io.h>
35#include <asm/irq.h>
36#include <asm/mach-au1x00/au1000.h>
37
38#if defined(CONFIG_SERIAL_AU1X00_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
39#define SUPPORT_SYSRQ
40#endif
41
42#include <linux/serial_core.h>
43#include "8250.h"
44
45/*
46 * Debugging.
47 */
48#if 0
49#define DEBUG_AUTOCONF(fmt...) printk(fmt)
50#else
51#define DEBUG_AUTOCONF(fmt...) do { } while (0)
52#endif
53
54#if 0
55#define DEBUG_INTR(fmt...) printk(fmt)
56#else
57#define DEBUG_INTR(fmt...) do { } while (0)
58#endif
59
60#define PASS_LIMIT 256
61
62/*
63 * We default to IRQ0 for the "no irq" hack. Some
64 * machine types want others as well - they're free
65 * to redefine this in their header file.
66 */
67#define is_real_interrupt(irq) ((irq) != 0)
68
69static struct old_serial_port old_serial_port[] = {
70 { .baud_base = 0,
71 .iomem_base = (u8 *)UART0_ADDR,
72 .irq = AU1000_UART0_INT,
73 .flags = STD_COM_FLAGS,
74 .iomem_reg_shift = 2,
75 }, {
76 .baud_base = 0,
77 .iomem_base = (u8 *)UART1_ADDR,
78 .irq = AU1000_UART1_INT,
79 .flags = STD_COM_FLAGS,
80 .iomem_reg_shift = 2
81 }, {
82 .baud_base = 0,
83 .iomem_base = (u8 *)UART2_ADDR,
84 .irq = AU1000_UART2_INT,
85 .flags = STD_COM_FLAGS,
86 .iomem_reg_shift = 2
87 }, {
88 .baud_base = 0,
89 .iomem_base = (u8 *)UART3_ADDR,
90 .irq = AU1000_UART3_INT,
91 .flags = STD_COM_FLAGS,
92 .iomem_reg_shift = 2
93 }
94};
95
96#define UART_NR ARRAY_SIZE(old_serial_port)
97
98struct uart_8250_port {
99 struct uart_port port;
100 struct timer_list timer; /* "no irq" timer */
101 struct list_head list; /* ports on this IRQ */
102 unsigned short rev;
103 unsigned char acr;
104 unsigned char ier;
105 unsigned char lcr;
106 unsigned char mcr_mask; /* mask of user bits */
107 unsigned char mcr_force; /* mask of forced bits */
108 unsigned char lsr_break_flag;
109
110 /*
111 * We provide a per-port pm hook.
112 */
113 void (*pm)(struct uart_port *port,
114 unsigned int state, unsigned int old);
115};
116
117struct irq_info {
118 spinlock_t lock;
119 struct list_head *head;
120};
121
122static struct irq_info irq_lists[NR_IRQS];
123
124/*
125 * Here we define the default xmit fifo size used for each type of UART.
126 */
127static const struct serial_uart_config uart_config[PORT_MAX_8250+1] = {
128 { "unknown", 1, 0 },
129 { "8250", 1, 0 },
130 { "16450", 1, 0 },
131 { "16550", 1, 0 },
132 /* PORT_16550A */
133 { "AU1X00_UART",16, UART_CLEAR_FIFO | UART_USE_FIFO },
134};
135
136static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset)
137{
138 return au_readl((unsigned long)up->port.membase + offset);
139}
140
141static _INLINE_ void
142serial_out(struct uart_8250_port *up, int offset, int value)
143{
144 au_writel(value, (unsigned long)up->port.membase + offset);
145}
146
147#define serial_inp(up, offset) serial_in(up, offset)
148#define serial_outp(up, offset, value) serial_out(up, offset, value)
149
150/*
151 * This routine is called by rs_init() to initialize a specific serial
152 * port. It determines what type of UART chip this serial port is
153 * using: 8250, 16450, 16550, 16550A. The important question is
154 * whether or not this UART is a 16550A or not, since this will
155 * determine whether or not we can use its FIFO features or not.
156 */
157static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
158{
159 unsigned char save_lcr, save_mcr;
160 unsigned long flags;
161
162 if (!up->port.iobase && !up->port.mapbase && !up->port.membase)
163 return;
164
165 DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04x, 0x%08lx): ",
166 up->port.line, up->port.iobase, up->port.membase);
167
168 /*
169 * We really do need global IRQs disabled here - we're going to
170 * be frobbing the chips IRQ enable register to see if it exists.
171 */
172 spin_lock_irqsave(&up->port.lock, flags);
173// save_flags(flags); cli();
174
175 save_mcr = serial_in(up, UART_MCR);
176 save_lcr = serial_in(up, UART_LCR);
177
178 up->port.type = PORT_16550A;
179 serial_outp(up, UART_LCR, save_lcr);
180
181 up->port.fifosize = uart_config[up->port.type].dfl_xmit_fifo_size;
182
183 if (up->port.type == PORT_UNKNOWN)
184 goto out;
185
186 /*
187 * Reset the UART.
188 */
189 serial_outp(up, UART_MCR, save_mcr);
190 serial_outp(up, UART_FCR, (UART_FCR_ENABLE_FIFO |
191 UART_FCR_CLEAR_RCVR |
192 UART_FCR_CLEAR_XMIT));
193 serial_outp(up, UART_FCR, 0);
194 (void)serial_in(up, UART_RX);
195 serial_outp(up, UART_IER, 0);
196
197 out:
198 spin_unlock_irqrestore(&up->port.lock, flags);
199// restore_flags(flags);
200 DEBUG_AUTOCONF("type=%s\n", uart_config[up->port.type].name);
201}
202
Russell Kingb129a8c2005-08-31 10:12:14 +0100203static void serial8250_stop_tx(struct uart_port *port)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204{
205 struct uart_8250_port *up = (struct uart_8250_port *)port;
206
207 if (up->ier & UART_IER_THRI) {
208 up->ier &= ~UART_IER_THRI;
209 serial_out(up, UART_IER, up->ier);
210 }
211}
212
Russell Kingb129a8c2005-08-31 10:12:14 +0100213static void serial8250_start_tx(struct uart_port *port)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214{
215 struct uart_8250_port *up = (struct uart_8250_port *)port;
216
217 if (!(up->ier & UART_IER_THRI)) {
218 up->ier |= UART_IER_THRI;
219 serial_out(up, UART_IER, up->ier);
220 }
221}
222
223static void serial8250_stop_rx(struct uart_port *port)
224{
225 struct uart_8250_port *up = (struct uart_8250_port *)port;
226
227 up->ier &= ~UART_IER_RLSI;
228 up->port.read_status_mask &= ~UART_LSR_DR;
229 serial_out(up, UART_IER, up->ier);
230}
231
232static void serial8250_enable_ms(struct uart_port *port)
233{
234 struct uart_8250_port *up = (struct uart_8250_port *)port;
235
236 up->ier |= UART_IER_MSI;
237 serial_out(up, UART_IER, up->ier);
238}
239
240static _INLINE_ void
241receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs)
242{
243 struct tty_struct *tty = up->port.info->tty;
244 unsigned char ch;
245 int max_count = 256;
246
247 do {
248 if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
249 tty->flip.work.func((void *)tty);
250 if (tty->flip.count >= TTY_FLIPBUF_SIZE)
251 return; // if TTY_DONT_FLIP is set
252 }
253 ch = serial_inp(up, UART_RX);
254 *tty->flip.char_buf_ptr = ch;
255 *tty->flip.flag_buf_ptr = TTY_NORMAL;
256 up->port.icount.rx++;
257
258 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
259 UART_LSR_FE | UART_LSR_OE))) {
260 /*
261 * For statistics only
262 */
263 if (*status & UART_LSR_BI) {
264 *status &= ~(UART_LSR_FE | UART_LSR_PE);
265 up->port.icount.brk++;
266 /*
267 * We do the SysRQ and SAK checking
268 * here because otherwise the break
269 * may get masked by ignore_status_mask
270 * or read_status_mask.
271 */
272 if (uart_handle_break(&up->port))
273 goto ignore_char;
274 } else if (*status & UART_LSR_PE)
275 up->port.icount.parity++;
276 else if (*status & UART_LSR_FE)
277 up->port.icount.frame++;
278 if (*status & UART_LSR_OE)
279 up->port.icount.overrun++;
280
281 /*
282 * Mask off conditions which should be ingored.
283 */
284 *status &= up->port.read_status_mask;
285
286#ifdef CONFIG_SERIAL_AU1X00_CONSOLE
287 if (up->port.line == up->port.cons->index) {
288 /* Recover the break flag from console xmit */
289 *status |= up->lsr_break_flag;
290 up->lsr_break_flag = 0;
291 }
292#endif
293 if (*status & UART_LSR_BI) {
294 DEBUG_INTR("handling break....");
295 *tty->flip.flag_buf_ptr = TTY_BREAK;
296 } else if (*status & UART_LSR_PE)
297 *tty->flip.flag_buf_ptr = TTY_PARITY;
298 else if (*status & UART_LSR_FE)
299 *tty->flip.flag_buf_ptr = TTY_FRAME;
300 }
301 if (uart_handle_sysrq_char(&up->port, ch, regs))
302 goto ignore_char;
303 if ((*status & up->port.ignore_status_mask) == 0) {
304 tty->flip.flag_buf_ptr++;
305 tty->flip.char_buf_ptr++;
306 tty->flip.count++;
307 }
308 if ((*status & UART_LSR_OE) &&
309 tty->flip.count < TTY_FLIPBUF_SIZE) {
310 /*
311 * Overrun is special, since it's reported
312 * immediately, and doesn't affect the current
313 * character.
314 */
315 *tty->flip.flag_buf_ptr = TTY_OVERRUN;
316 tty->flip.flag_buf_ptr++;
317 tty->flip.char_buf_ptr++;
318 tty->flip.count++;
319 }
320 ignore_char:
321 *status = serial_inp(up, UART_LSR);
322 } while ((*status & UART_LSR_DR) && (max_count-- > 0));
323 spin_unlock(&up->port.lock);
324 tty_flip_buffer_push(tty);
325 spin_lock(&up->port.lock);
326}
327
328static _INLINE_ void transmit_chars(struct uart_8250_port *up)
329{
330 struct circ_buf *xmit = &up->port.info->xmit;
331 int count;
332
333 if (up->port.x_char) {
334 serial_outp(up, UART_TX, up->port.x_char);
335 up->port.icount.tx++;
336 up->port.x_char = 0;
337 return;
338 }
339 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
Russell Kingb129a8c2005-08-31 10:12:14 +0100340 serial8250_stop_tx(&up->port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 return;
342 }
343
344 count = up->port.fifosize;
345 do {
346 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
347 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
348 up->port.icount.tx++;
349 if (uart_circ_empty(xmit))
350 break;
351 } while (--count > 0);
352
353 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
354 uart_write_wakeup(&up->port);
355
356 DEBUG_INTR("THRE...");
357
358 if (uart_circ_empty(xmit))
Russell Kingb129a8c2005-08-31 10:12:14 +0100359 serial8250_stop_tx(&up->port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360}
361
362static _INLINE_ void check_modem_status(struct uart_8250_port *up)
363{
364 int status;
365
366 status = serial_in(up, UART_MSR);
367
368 if ((status & UART_MSR_ANY_DELTA) == 0)
369 return;
370
371 if (status & UART_MSR_TERI)
372 up->port.icount.rng++;
373 if (status & UART_MSR_DDSR)
374 up->port.icount.dsr++;
375 if (status & UART_MSR_DDCD)
376 uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
377 if (status & UART_MSR_DCTS)
378 uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
379
380 wake_up_interruptible(&up->port.info->delta_msr_wait);
381}
382
383/*
384 * This handles the interrupt from one port.
385 */
386static inline void
387serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs)
388{
389 unsigned int status = serial_inp(up, UART_LSR);
390
391 DEBUG_INTR("status = %x...", status);
392
393 if (status & UART_LSR_DR)
394 receive_chars(up, &status, regs);
395 check_modem_status(up);
396 if (status & UART_LSR_THRE)
397 transmit_chars(up);
398}
399
400/*
401 * This is the serial driver's interrupt routine.
402 *
403 * Arjan thinks the old way was overly complex, so it got simplified.
404 * Alan disagrees, saying that need the complexity to handle the weird
405 * nature of ISA shared interrupts. (This is a special exception.)
406 *
407 * In order to handle ISA shared interrupts properly, we need to check
408 * that all ports have been serviced, and therefore the ISA interrupt
409 * line has been de-asserted.
410 *
411 * This means we need to loop through all ports. checking that they
412 * don't have an interrupt pending.
413 */
414static irqreturn_t serial8250_interrupt(int irq, void *dev_id, struct pt_regs *regs)
415{
416 struct irq_info *i = dev_id;
417 struct list_head *l, *end = NULL;
418 int pass_counter = 0;
419
420 DEBUG_INTR("serial8250_interrupt(%d)...", irq);
421
422 spin_lock(&i->lock);
423
424 l = i->head;
425 do {
426 struct uart_8250_port *up;
427 unsigned int iir;
428
429 up = list_entry(l, struct uart_8250_port, list);
430
431 iir = serial_in(up, UART_IIR);
432 if (!(iir & UART_IIR_NO_INT)) {
433 spin_lock(&up->port.lock);
434 serial8250_handle_port(up, regs);
435 spin_unlock(&up->port.lock);
436
437 end = NULL;
438 } else if (end == NULL)
439 end = l;
440
441 l = l->next;
442
443 if (l == i->head && pass_counter++ > PASS_LIMIT) {
444 /* If we hit this, we're dead. */
445 printk(KERN_ERR "serial8250: too much work for "
446 "irq%d\n", irq);
447 break;
448 }
449 } while (l != end);
450
451 spin_unlock(&i->lock);
452
453 DEBUG_INTR("end.\n");
454 /* FIXME! Was it really ours? */
455 return IRQ_HANDLED;
456}
457
458/*
459 * To support ISA shared interrupts, we need to have one interrupt
460 * handler that ensures that the IRQ line has been deasserted
461 * before returning. Failing to do this will result in the IRQ
462 * line being stuck active, and, since ISA irqs are edge triggered,
463 * no more IRQs will be seen.
464 */
465static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
466{
467 spin_lock_irq(&i->lock);
468
469 if (!list_empty(i->head)) {
470 if (i->head == &up->list)
471 i->head = i->head->next;
472 list_del(&up->list);
473 } else {
474 BUG_ON(i->head != &up->list);
475 i->head = NULL;
476 }
477
478 spin_unlock_irq(&i->lock);
479}
480
481static int serial_link_irq_chain(struct uart_8250_port *up)
482{
483 struct irq_info *i = irq_lists + up->port.irq;
484 int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? SA_SHIRQ : 0;
485
486 spin_lock_irq(&i->lock);
487
488 if (i->head) {
489 list_add(&up->list, i->head);
490 spin_unlock_irq(&i->lock);
491
492 ret = 0;
493 } else {
494 INIT_LIST_HEAD(&up->list);
495 i->head = &up->list;
496 spin_unlock_irq(&i->lock);
497
498 ret = request_irq(up->port.irq, serial8250_interrupt,
499 irq_flags, "serial", i);
500 if (ret < 0)
501 serial_do_unlink(i, up);
502 }
503
504 return ret;
505}
506
507static void serial_unlink_irq_chain(struct uart_8250_port *up)
508{
509 struct irq_info *i = irq_lists + up->port.irq;
510
511 BUG_ON(i->head == NULL);
512
513 if (list_empty(i->head))
514 free_irq(up->port.irq, i);
515
516 serial_do_unlink(i, up);
517}
518
519/*
520 * This function is used to handle ports that do not have an
521 * interrupt. This doesn't work very well for 16450's, but gives
522 * barely passable results for a 16550A. (Although at the expense
523 * of much CPU overhead).
524 */
525static void serial8250_timeout(unsigned long data)
526{
527 struct uart_8250_port *up = (struct uart_8250_port *)data;
528 unsigned int timeout;
529 unsigned int iir;
530
531 iir = serial_in(up, UART_IIR);
532 if (!(iir & UART_IIR_NO_INT)) {
533 spin_lock(&up->port.lock);
534 serial8250_handle_port(up, NULL);
535 spin_unlock(&up->port.lock);
536 }
537
538 timeout = up->port.timeout;
539 timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
540 mod_timer(&up->timer, jiffies + timeout);
541}
542
543static unsigned int serial8250_tx_empty(struct uart_port *port)
544{
545 struct uart_8250_port *up = (struct uart_8250_port *)port;
546 unsigned long flags;
547 unsigned int ret;
548
549 spin_lock_irqsave(&up->port.lock, flags);
550 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
551 spin_unlock_irqrestore(&up->port.lock, flags);
552
553 return ret;
554}
555
556static unsigned int serial8250_get_mctrl(struct uart_port *port)
557{
558 struct uart_8250_port *up = (struct uart_8250_port *)port;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 unsigned char status;
560 unsigned int ret;
561
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 status = serial_in(up, UART_MSR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563
564 ret = 0;
565 if (status & UART_MSR_DCD)
566 ret |= TIOCM_CAR;
567 if (status & UART_MSR_RI)
568 ret |= TIOCM_RNG;
569 if (status & UART_MSR_DSR)
570 ret |= TIOCM_DSR;
571 if (status & UART_MSR_CTS)
572 ret |= TIOCM_CTS;
573 return ret;
574}
575
576static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
577{
578 struct uart_8250_port *up = (struct uart_8250_port *)port;
579 unsigned char mcr = 0;
580
581 if (mctrl & TIOCM_RTS)
582 mcr |= UART_MCR_RTS;
583 if (mctrl & TIOCM_DTR)
584 mcr |= UART_MCR_DTR;
585 if (mctrl & TIOCM_OUT1)
586 mcr |= UART_MCR_OUT1;
587 if (mctrl & TIOCM_OUT2)
588 mcr |= UART_MCR_OUT2;
589 if (mctrl & TIOCM_LOOP)
590 mcr |= UART_MCR_LOOP;
591
592 mcr = (mcr & up->mcr_mask) | up->mcr_force;
593
594 serial_out(up, UART_MCR, mcr);
595}
596
597static void serial8250_break_ctl(struct uart_port *port, int break_state)
598{
599 struct uart_8250_port *up = (struct uart_8250_port *)port;
600 unsigned long flags;
601
602 spin_lock_irqsave(&up->port.lock, flags);
603 if (break_state == -1)
604 up->lcr |= UART_LCR_SBC;
605 else
606 up->lcr &= ~UART_LCR_SBC;
607 serial_out(up, UART_LCR, up->lcr);
608 spin_unlock_irqrestore(&up->port.lock, flags);
609}
610
611static int serial8250_startup(struct uart_port *port)
612{
613 struct uart_8250_port *up = (struct uart_8250_port *)port;
614 unsigned long flags;
615 int retval;
616
617 /*
618 * Clear the FIFO buffers and disable them.
619 * (they will be reeanbled in set_termios())
620 */
621 if (uart_config[up->port.type].flags & UART_CLEAR_FIFO) {
622 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
623 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
624 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
625 serial_outp(up, UART_FCR, 0);
626 }
627
628 /*
629 * Clear the interrupt registers.
630 */
631 (void) serial_inp(up, UART_LSR);
632 (void) serial_inp(up, UART_RX);
633 (void) serial_inp(up, UART_IIR);
634 (void) serial_inp(up, UART_MSR);
635
636 /*
637 * At this point, there's no way the LSR could still be 0xff;
638 * if it is, then bail out, because there's likely no UART
639 * here.
640 */
641 if (!(up->port.flags & UPF_BUGGY_UART) &&
642 (serial_inp(up, UART_LSR) == 0xff)) {
643 printk("ttyS%d: LSR safety check engaged!\n", up->port.line);
644 return -ENODEV;
645 }
646
647 retval = serial_link_irq_chain(up);
648 if (retval)
649 return retval;
650
651 /*
652 * Now, initialize the UART
653 */
654 serial_outp(up, UART_LCR, UART_LCR_WLEN8);
655
656 spin_lock_irqsave(&up->port.lock, flags);
657 if (up->port.flags & UPF_FOURPORT) {
658 if (!is_real_interrupt(up->port.irq))
659 up->port.mctrl |= TIOCM_OUT1;
660 } else
661 /*
662 * Most PC uarts need OUT2 raised to enable interrupts.
663 */
664 if (is_real_interrupt(up->port.irq))
665 up->port.mctrl |= TIOCM_OUT2;
666
667 serial8250_set_mctrl(&up->port, up->port.mctrl);
668 spin_unlock_irqrestore(&up->port.lock, flags);
669
670 /*
671 * Finally, enable interrupts. Note: Modem status interrupts
672 * are set via set_termios(), which will be occurring imminently
673 * anyway, so we don't enable them here.
674 */
675 up->ier = UART_IER_RLSI | UART_IER_RDI;
676 serial_outp(up, UART_IER, up->ier);
677
678 if (up->port.flags & UPF_FOURPORT) {
679 unsigned int icp;
680 /*
681 * Enable interrupts on the AST Fourport board
682 */
683 icp = (up->port.iobase & 0xfe0) | 0x01f;
684 outb_p(0x80, icp);
685 (void) inb_p(icp);
686 }
687
688 /*
689 * And clear the interrupt registers again for luck.
690 */
691 (void) serial_inp(up, UART_LSR);
692 (void) serial_inp(up, UART_RX);
693 (void) serial_inp(up, UART_IIR);
694 (void) serial_inp(up, UART_MSR);
695
696 return 0;
697}
698
699static void serial8250_shutdown(struct uart_port *port)
700{
701 struct uart_8250_port *up = (struct uart_8250_port *)port;
702 unsigned long flags;
703
704 /*
705 * Disable interrupts from this port
706 */
707 up->ier = 0;
708 serial_outp(up, UART_IER, 0);
709
710 spin_lock_irqsave(&up->port.lock, flags);
711 if (up->port.flags & UPF_FOURPORT) {
712 /* reset interrupts on the AST Fourport board */
713 inb((up->port.iobase & 0xfe0) | 0x1f);
714 up->port.mctrl |= TIOCM_OUT1;
715 } else
716 up->port.mctrl &= ~TIOCM_OUT2;
717
718 serial8250_set_mctrl(&up->port, up->port.mctrl);
719 spin_unlock_irqrestore(&up->port.lock, flags);
720
721 /*
722 * Disable break condition and FIFOs
723 */
724 serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC);
725 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
726 UART_FCR_CLEAR_RCVR |
727 UART_FCR_CLEAR_XMIT);
728 serial_outp(up, UART_FCR, 0);
729
730 /*
731 * Read data port to reset things, and then unlink from
732 * the IRQ chain.
733 */
734 (void) serial_in(up, UART_RX);
735
736 if (!is_real_interrupt(up->port.irq))
737 del_timer_sync(&up->timer);
738 else
739 serial_unlink_irq_chain(up);
740}
741
742static unsigned int serial8250_get_divisor(struct uart_port *port, unsigned int baud)
743{
744 unsigned int quot;
745
746 /*
747 * Handle magic divisors for baud rates above baud_base on
748 * SMSC SuperIO chips.
749 */
750 if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
751 baud == (port->uartclk/4))
752 quot = 0x8001;
753 else if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
754 baud == (port->uartclk/8))
755 quot = 0x8002;
756 else
757 quot = uart_get_divisor(port, baud);
758
759 return quot;
760}
761
762static void
763serial8250_set_termios(struct uart_port *port, struct termios *termios,
764 struct termios *old)
765{
766 struct uart_8250_port *up = (struct uart_8250_port *)port;
767 unsigned char cval, fcr = 0;
768 unsigned long flags;
769 unsigned int baud, quot;
770
771 switch (termios->c_cflag & CSIZE) {
772 case CS5:
Russell King0a8b80c52005-06-24 19:48:22 +0100773 cval = UART_LCR_WLEN5;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774 break;
775 case CS6:
Russell King0a8b80c52005-06-24 19:48:22 +0100776 cval = UART_LCR_WLEN6;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777 break;
778 case CS7:
Russell King0a8b80c52005-06-24 19:48:22 +0100779 cval = UART_LCR_WLEN7;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780 break;
781 default:
782 case CS8:
Russell King0a8b80c52005-06-24 19:48:22 +0100783 cval = UART_LCR_WLEN8;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 break;
785 }
786
787 if (termios->c_cflag & CSTOPB)
Russell King0a8b80c52005-06-24 19:48:22 +0100788 cval |= UART_LCR_STOP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 if (termios->c_cflag & PARENB)
790 cval |= UART_LCR_PARITY;
791 if (!(termios->c_cflag & PARODD))
792 cval |= UART_LCR_EPAR;
793#ifdef CMSPAR
794 if (termios->c_cflag & CMSPAR)
795 cval |= UART_LCR_SPAR;
796#endif
797
798 /*
799 * Ask the core to calculate the divisor for us.
800 */
801 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
802 quot = serial8250_get_divisor(port, baud);
803 quot = 0x35; /* FIXME */
804
805 /*
806 * Work around a bug in the Oxford Semiconductor 952 rev B
807 * chip which causes it to seriously miscalculate baud rates
808 * when DLL is 0.
809 */
810 if ((quot & 0xff) == 0 && up->port.type == PORT_16C950 &&
811 up->rev == 0x5201)
812 quot ++;
813
814 if (uart_config[up->port.type].flags & UART_USE_FIFO) {
815 if (baud < 2400)
816 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_1;
817 else
818 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_8;
819 }
820
821 /*
822 * Ok, we're now changing the port state. Do it with
823 * interrupts disabled.
824 */
825 spin_lock_irqsave(&up->port.lock, flags);
826
827 /*
828 * Update the per-port timeout.
829 */
830 uart_update_timeout(port, termios->c_cflag, baud);
831
832 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
833 if (termios->c_iflag & INPCK)
834 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
835 if (termios->c_iflag & (BRKINT | PARMRK))
836 up->port.read_status_mask |= UART_LSR_BI;
837
838 /*
839 * Characteres to ignore
840 */
841 up->port.ignore_status_mask = 0;
842 if (termios->c_iflag & IGNPAR)
843 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
844 if (termios->c_iflag & IGNBRK) {
845 up->port.ignore_status_mask |= UART_LSR_BI;
846 /*
847 * If we're ignoring parity and break indicators,
848 * ignore overruns too (for real raw support).
849 */
850 if (termios->c_iflag & IGNPAR)
851 up->port.ignore_status_mask |= UART_LSR_OE;
852 }
853
854 /*
855 * ignore all characters if CREAD is not set
856 */
857 if ((termios->c_cflag & CREAD) == 0)
858 up->port.ignore_status_mask |= UART_LSR_DR;
859
860 /*
861 * CTS flow control flag and modem status interrupts
862 */
863 up->ier &= ~UART_IER_MSI;
864 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
865 up->ier |= UART_IER_MSI;
866
867 serial_out(up, UART_IER, up->ier);
868 serial_outp(up, 0x28, quot & 0xffff);
869 up->lcr = cval; /* Save LCR */
870 if (up->port.type != PORT_16750) {
871 if (fcr & UART_FCR_ENABLE_FIFO) {
872 /* emulated UARTs (Lucent Venus 167x) need two steps */
873 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
874 }
875 serial_outp(up, UART_FCR, fcr); /* set fcr */
876 }
877 spin_unlock_irqrestore(&up->port.lock, flags);
878}
879
880static void
881serial8250_pm(struct uart_port *port, unsigned int state,
882 unsigned int oldstate)
883{
884 struct uart_8250_port *up = (struct uart_8250_port *)port;
885 if (state) {
886 /* sleep */
887 if (up->pm)
888 up->pm(port, state, oldstate);
889 } else {
890 /* wake */
891 if (up->pm)
892 up->pm(port, state, oldstate);
893 }
894}
895
896/*
897 * Resource handling. This is complicated by the fact that resources
898 * depend on the port type. Maybe we should be claiming the standard
899 * 8250 ports, and then trying to get other resources as necessary?
900 */
901static int
902serial8250_request_std_resource(struct uart_8250_port *up, struct resource **res)
903{
904 unsigned int size = 8 << up->port.regshift;
905 int ret = 0;
906
907 switch (up->port.iotype) {
908 case SERIAL_IO_MEM:
909 if (up->port.mapbase) {
910 *res = request_mem_region(up->port.mapbase, size, "serial");
911 if (!*res)
912 ret = -EBUSY;
913 }
914 break;
915
916 case SERIAL_IO_HUB6:
917 case SERIAL_IO_PORT:
918 *res = request_region(up->port.iobase, size, "serial");
919 if (!*res)
920 ret = -EBUSY;
921 break;
922 }
923 return ret;
924}
925
926
927static void serial8250_release_port(struct uart_port *port)
928{
929 struct uart_8250_port *up = (struct uart_8250_port *)port;
930 unsigned long start, offset = 0, size = 0;
931
932 size <<= up->port.regshift;
933
934 switch (up->port.iotype) {
935 case SERIAL_IO_MEM:
936 if (up->port.mapbase) {
937 /*
938 * Unmap the area.
939 */
940 iounmap(up->port.membase);
941 up->port.membase = NULL;
942
943 start = up->port.mapbase;
944
945 if (size)
946 release_mem_region(start + offset, size);
947 release_mem_region(start, 8 << up->port.regshift);
948 }
949 break;
950
951 case SERIAL_IO_HUB6:
952 case SERIAL_IO_PORT:
953 start = up->port.iobase;
954
955 if (size)
956 release_region(start + offset, size);
957 release_region(start + offset, 8 << up->port.regshift);
958 break;
959
960 default:
961 break;
962 }
963}
964
965static int serial8250_request_port(struct uart_port *port)
966{
967 struct uart_8250_port *up = (struct uart_8250_port *)port;
968 struct resource *res = NULL, *res_rsa = NULL;
969 int ret = 0;
970
971 ret = serial8250_request_std_resource(up, &res);
972
973 /*
974 * If we have a mapbase, then request that as well.
975 */
976 if (ret == 0 && up->port.flags & UPF_IOREMAP) {
977 int size = res->end - res->start + 1;
978
979 up->port.membase = ioremap(up->port.mapbase, size);
980 if (!up->port.membase)
981 ret = -ENOMEM;
982 }
983
984 if (ret < 0) {
985 if (res_rsa)
986 release_resource(res_rsa);
987 if (res)
988 release_resource(res);
989 }
990 return ret;
991}
992
993static void serial8250_config_port(struct uart_port *port, int flags)
994{
995 struct uart_8250_port *up = (struct uart_8250_port *)port;
996 struct resource *res_std = NULL, *res_rsa = NULL;
997 int probeflags = PROBE_ANY;
998
999 probeflags &= ~PROBE_RSA;
1000
1001 if (flags & UART_CONFIG_TYPE)
1002 autoconfig(up, probeflags);
1003
1004 /*
1005 * If the port wasn't an RSA port, release the resource.
1006 */
1007 if (up->port.type != PORT_RSA && res_rsa)
1008 release_resource(res_rsa);
1009
1010 if (up->port.type == PORT_UNKNOWN && res_std)
1011 release_resource(res_std);
1012}
1013
1014static int
1015serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
1016{
1017 if (ser->irq >= NR_IRQS || ser->irq < 0 ||
1018 ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
1019 ser->type > PORT_MAX_8250 || ser->type == PORT_CIRRUS ||
1020 ser->type == PORT_STARTECH)
1021 return -EINVAL;
1022 return 0;
1023}
1024
1025static const char *
1026serial8250_type(struct uart_port *port)
1027{
1028 int type = port->type;
1029
1030 if (type >= ARRAY_SIZE(uart_config))
1031 type = 0;
1032 return uart_config[type].name;
1033}
1034
1035static struct uart_ops serial8250_pops = {
1036 .tx_empty = serial8250_tx_empty,
1037 .set_mctrl = serial8250_set_mctrl,
1038 .get_mctrl = serial8250_get_mctrl,
1039 .stop_tx = serial8250_stop_tx,
1040 .start_tx = serial8250_start_tx,
1041 .stop_rx = serial8250_stop_rx,
1042 .enable_ms = serial8250_enable_ms,
1043 .break_ctl = serial8250_break_ctl,
1044 .startup = serial8250_startup,
1045 .shutdown = serial8250_shutdown,
1046 .set_termios = serial8250_set_termios,
1047 .pm = serial8250_pm,
1048 .type = serial8250_type,
1049 .release_port = serial8250_release_port,
1050 .request_port = serial8250_request_port,
1051 .config_port = serial8250_config_port,
1052 .verify_port = serial8250_verify_port,
1053};
1054
1055static struct uart_8250_port serial8250_ports[UART_NR];
1056
1057static void __init serial8250_isa_init_ports(void)
1058{
1059 struct uart_8250_port *up;
1060 static int first = 1;
1061 int i;
1062
1063 if (!first)
1064 return;
1065 first = 0;
1066
1067 for (i = 0, up = serial8250_ports; i < ARRAY_SIZE(old_serial_port);
1068 i++, up++) {
1069 up->port.iobase = old_serial_port[i].port;
1070 up->port.irq = old_serial_port[i].irq;
1071 up->port.uartclk = get_au1x00_uart_baud_base();
1072 up->port.flags = old_serial_port[i].flags;
1073 up->port.hub6 = old_serial_port[i].hub6;
1074 up->port.membase = old_serial_port[i].iomem_base;
1075 up->port.iotype = old_serial_port[i].io_type;
1076 up->port.regshift = old_serial_port[i].iomem_reg_shift;
1077 up->port.ops = &serial8250_pops;
1078 }
1079}
1080
1081static void __init serial8250_register_ports(struct uart_driver *drv)
1082{
1083 int i;
1084
1085 serial8250_isa_init_ports();
1086
1087 for (i = 0; i < UART_NR; i++) {
1088 struct uart_8250_port *up = &serial8250_ports[i];
1089
1090 up->port.line = i;
1091 up->port.ops = &serial8250_pops;
1092 init_timer(&up->timer);
1093 up->timer.function = serial8250_timeout;
1094
1095 /*
1096 * ALPHA_KLUDGE_MCR needs to be killed.
1097 */
1098 up->mcr_mask = ~ALPHA_KLUDGE_MCR;
1099 up->mcr_force = ALPHA_KLUDGE_MCR;
1100
1101 uart_add_one_port(drv, &up->port);
1102 }
1103}
1104
1105#ifdef CONFIG_SERIAL_AU1X00_CONSOLE
1106
1107#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1108
1109/*
1110 * Wait for transmitter & holding register to empty
1111 */
1112static inline void wait_for_xmitr(struct uart_8250_port *up)
1113{
1114 unsigned int status, tmout = 10000;
1115
1116 /* Wait up to 10ms for the character(s) to be sent. */
1117 do {
1118 status = serial_in(up, UART_LSR);
1119
1120 if (status & UART_LSR_BI)
1121 up->lsr_break_flag = UART_LSR_BI;
1122
1123 if (--tmout == 0)
1124 break;
1125 udelay(1);
1126 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1127
1128 /* Wait up to 1s for flow control if necessary */
1129 if (up->port.flags & UPF_CONS_FLOW) {
1130 tmout = 1000000;
1131 while (--tmout &&
1132 ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
1133 udelay(1);
1134 }
1135}
1136
1137/*
1138 * Print a string to the serial port trying not to disturb
1139 * any possible real use of the port...
1140 *
1141 * The console_lock must be held when we get here.
1142 */
1143static void
1144serial8250_console_write(struct console *co, const char *s, unsigned int count)
1145{
1146 struct uart_8250_port *up = &serial8250_ports[co->index];
1147 unsigned int ier;
1148 int i;
1149
1150 /*
1151 * First save the UER then disable the interrupts
1152 */
1153 ier = serial_in(up, UART_IER);
1154 serial_out(up, UART_IER, 0);
1155
1156 /*
1157 * Now, do each character
1158 */
1159 for (i = 0; i < count; i++, s++) {
1160 wait_for_xmitr(up);
1161
1162 /*
1163 * Send the character out.
1164 * If a LF, also do CR...
1165 */
1166 serial_out(up, UART_TX, *s);
1167 if (*s == 10) {
1168 wait_for_xmitr(up);
1169 serial_out(up, UART_TX, 13);
1170 }
1171 }
1172
1173 /*
1174 * Finally, wait for transmitter to become empty
1175 * and restore the IER
1176 */
1177 wait_for_xmitr(up);
1178 serial_out(up, UART_IER, ier);
1179}
1180
1181static int __init serial8250_console_setup(struct console *co, char *options)
1182{
1183 struct uart_port *port;
1184 int baud = 9600;
1185 int bits = 8;
1186 int parity = 'n';
1187 int flow = 'n';
1188
1189 /*
1190 * Check whether an invalid uart number has been specified, and
1191 * if so, search for the first available port that does have
1192 * console support.
1193 */
1194 if (co->index >= UART_NR)
1195 co->index = 0;
1196 port = &serial8250_ports[co->index].port;
1197
1198 /*
1199 * Temporary fix.
1200 */
1201 spin_lock_init(&port->lock);
1202
1203 if (options)
1204 uart_parse_options(options, &baud, &parity, &bits, &flow);
1205
1206 return uart_set_options(port, co, baud, parity, bits, flow);
1207}
1208
1209extern struct uart_driver serial8250_reg;
1210static struct console serial8250_console = {
1211 .name = "ttyS",
1212 .write = serial8250_console_write,
1213 .device = uart_console_device,
1214 .setup = serial8250_console_setup,
1215 .flags = CON_PRINTBUFFER,
1216 .index = -1,
1217 .data = &serial8250_reg,
1218};
1219
1220static int __init serial8250_console_init(void)
1221{
1222 serial8250_isa_init_ports();
1223 register_console(&serial8250_console);
1224 return 0;
1225}
1226console_initcall(serial8250_console_init);
1227
1228#define SERIAL8250_CONSOLE &serial8250_console
1229#else
1230#define SERIAL8250_CONSOLE NULL
1231#endif
1232
1233static struct uart_driver serial8250_reg = {
1234 .owner = THIS_MODULE,
1235 .driver_name = "serial",
1236 .devfs_name = "tts/",
1237 .dev_name = "ttyS",
1238 .major = TTY_MAJOR,
1239 .minor = 64,
1240 .nr = UART_NR,
1241 .cons = SERIAL8250_CONSOLE,
1242};
1243
1244int __init early_serial_setup(struct uart_port *port)
1245{
1246 serial8250_isa_init_ports();
1247 serial8250_ports[port->line].port = *port;
1248 serial8250_ports[port->line].port.ops = &serial8250_pops;
1249 return 0;
1250}
1251
1252/**
1253 * serial8250_suspend_port - suspend one serial port
1254 * @line: serial line number
1255 * @level: the level of port suspension, as per uart_suspend_port
1256 *
1257 * Suspend one serial port.
1258 */
1259void serial8250_suspend_port(int line)
1260{
1261 uart_suspend_port(&serial8250_reg, &serial8250_ports[line].port);
1262}
1263
1264/**
1265 * serial8250_resume_port - resume one serial port
1266 * @line: serial line number
1267 * @level: the level of port resumption, as per uart_resume_port
1268 *
1269 * Resume one serial port.
1270 */
1271void serial8250_resume_port(int line)
1272{
1273 uart_resume_port(&serial8250_reg, &serial8250_ports[line].port);
1274}
1275
1276static int __init serial8250_init(void)
1277{
1278 int ret, i;
1279
1280 printk(KERN_INFO "Serial: Au1x00 driver\n");
1281
1282 for (i = 0; i < NR_IRQS; i++)
1283 spin_lock_init(&irq_lists[i].lock);
1284
1285 ret = uart_register_driver(&serial8250_reg);
1286 if (ret >= 0)
1287 serial8250_register_ports(&serial8250_reg);
1288
1289 return ret;
1290}
1291
1292static void __exit serial8250_exit(void)
1293{
1294 int i;
1295
1296 for (i = 0; i < UART_NR; i++)
1297 uart_remove_one_port(&serial8250_reg, &serial8250_ports[i].port);
1298
1299 uart_unregister_driver(&serial8250_reg);
1300}
1301
1302module_init(serial8250_init);
1303module_exit(serial8250_exit);
1304
1305EXPORT_SYMBOL(serial8250_suspend_port);
1306EXPORT_SYMBOL(serial8250_resume_port);
1307
1308MODULE_LICENSE("GPL");
1309MODULE_DESCRIPTION("Au1x00 serial driver\n");