xref: /openbmc/linux/drivers/tty/serial/sa1100.c (revision 81de3bf3)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  Driver for SA11x0 serial ports
4  *
5  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
6  *
7  *  Copyright (C) 2000 Deep Blue Solutions Ltd.
8  */
9 
10 #if defined(CONFIG_SERIAL_SA1100_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
11 #define SUPPORT_SYSRQ
12 #endif
13 
14 #include <linux/module.h>
15 #include <linux/ioport.h>
16 #include <linux/init.h>
17 #include <linux/console.h>
18 #include <linux/sysrq.h>
19 #include <linux/platform_data/sa11x0-serial.h>
20 #include <linux/platform_device.h>
21 #include <linux/tty.h>
22 #include <linux/tty_flip.h>
23 #include <linux/serial_core.h>
24 #include <linux/serial.h>
25 #include <linux/io.h>
26 
27 #include <asm/irq.h>
28 #include <mach/hardware.h>
29 #include <mach/irqs.h>
30 
31 #include "serial_mctrl_gpio.h"
32 
33 /* We've been assigned a range on the "Low-density serial ports" major */
34 #define SERIAL_SA1100_MAJOR	204
35 #define MINOR_START		5
36 
37 #define NR_PORTS		3
38 
39 #define SA1100_ISR_PASS_LIMIT	256
40 
41 /*
42  * Convert from ignore_status_mask or read_status_mask to UTSR[01]
43  */
44 #define SM_TO_UTSR0(x)	((x) & 0xff)
45 #define SM_TO_UTSR1(x)	((x) >> 8)
46 #define UTSR0_TO_SM(x)	((x))
47 #define UTSR1_TO_SM(x)	((x) << 8)
48 
49 #define UART_GET_UTCR0(sport)	__raw_readl((sport)->port.membase + UTCR0)
50 #define UART_GET_UTCR1(sport)	__raw_readl((sport)->port.membase + UTCR1)
51 #define UART_GET_UTCR2(sport)	__raw_readl((sport)->port.membase + UTCR2)
52 #define UART_GET_UTCR3(sport)	__raw_readl((sport)->port.membase + UTCR3)
53 #define UART_GET_UTSR0(sport)	__raw_readl((sport)->port.membase + UTSR0)
54 #define UART_GET_UTSR1(sport)	__raw_readl((sport)->port.membase + UTSR1)
55 #define UART_GET_CHAR(sport)	__raw_readl((sport)->port.membase + UTDR)
56 
57 #define UART_PUT_UTCR0(sport,v)	__raw_writel((v),(sport)->port.membase + UTCR0)
58 #define UART_PUT_UTCR1(sport,v)	__raw_writel((v),(sport)->port.membase + UTCR1)
59 #define UART_PUT_UTCR2(sport,v)	__raw_writel((v),(sport)->port.membase + UTCR2)
60 #define UART_PUT_UTCR3(sport,v)	__raw_writel((v),(sport)->port.membase + UTCR3)
61 #define UART_PUT_UTSR0(sport,v)	__raw_writel((v),(sport)->port.membase + UTSR0)
62 #define UART_PUT_UTSR1(sport,v)	__raw_writel((v),(sport)->port.membase + UTSR1)
63 #define UART_PUT_CHAR(sport,v)	__raw_writel((v),(sport)->port.membase + UTDR)
64 
65 /*
66  * This is the size of our serial port register set.
67  */
68 #define UART_PORT_SIZE	0x24
69 
70 /*
71  * This determines how often we check the modem status signals
72  * for any change.  They generally aren't connected to an IRQ
73  * so we have to poll them.  We also check immediately before
74  * filling the TX fifo incase CTS has been dropped.
75  */
76 #define MCTRL_TIMEOUT	(250*HZ/1000)
77 
78 struct sa1100_port {
79 	struct uart_port	port;
80 	struct timer_list	timer;
81 	unsigned int		old_status;
82 	struct mctrl_gpios	*gpios;
83 };
84 
85 /*
86  * Handle any change of modem status signal since we were last called.
87  */
88 static void sa1100_mctrl_check(struct sa1100_port *sport)
89 {
90 	unsigned int status, changed;
91 
92 	status = sport->port.ops->get_mctrl(&sport->port);
93 	changed = status ^ sport->old_status;
94 
95 	if (changed == 0)
96 		return;
97 
98 	sport->old_status = status;
99 
100 	if (changed & TIOCM_RI)
101 		sport->port.icount.rng++;
102 	if (changed & TIOCM_DSR)
103 		sport->port.icount.dsr++;
104 	if (changed & TIOCM_CAR)
105 		uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
106 	if (changed & TIOCM_CTS)
107 		uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
108 
109 	wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
110 }
111 
112 /*
113  * This is our per-port timeout handler, for checking the
114  * modem status signals.
115  */
116 static void sa1100_timeout(struct timer_list *t)
117 {
118 	struct sa1100_port *sport = from_timer(sport, t, timer);
119 	unsigned long flags;
120 
121 	if (sport->port.state) {
122 		spin_lock_irqsave(&sport->port.lock, flags);
123 		sa1100_mctrl_check(sport);
124 		spin_unlock_irqrestore(&sport->port.lock, flags);
125 
126 		mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
127 	}
128 }
129 
130 /*
131  * interrupts disabled on entry
132  */
133 static void sa1100_stop_tx(struct uart_port *port)
134 {
135 	struct sa1100_port *sport =
136 		container_of(port, struct sa1100_port, port);
137 	u32 utcr3;
138 
139 	utcr3 = UART_GET_UTCR3(sport);
140 	UART_PUT_UTCR3(sport, utcr3 & ~UTCR3_TIE);
141 	sport->port.read_status_mask &= ~UTSR0_TO_SM(UTSR0_TFS);
142 }
143 
144 /*
145  * port locked and interrupts disabled
146  */
147 static void sa1100_start_tx(struct uart_port *port)
148 {
149 	struct sa1100_port *sport =
150 		container_of(port, struct sa1100_port, port);
151 	u32 utcr3;
152 
153 	utcr3 = UART_GET_UTCR3(sport);
154 	sport->port.read_status_mask |= UTSR0_TO_SM(UTSR0_TFS);
155 	UART_PUT_UTCR3(sport, utcr3 | UTCR3_TIE);
156 }
157 
158 /*
159  * Interrupts enabled
160  */
161 static void sa1100_stop_rx(struct uart_port *port)
162 {
163 	struct sa1100_port *sport =
164 		container_of(port, struct sa1100_port, port);
165 	u32 utcr3;
166 
167 	utcr3 = UART_GET_UTCR3(sport);
168 	UART_PUT_UTCR3(sport, utcr3 & ~UTCR3_RIE);
169 }
170 
171 /*
172  * Set the modem control timer to fire immediately.
173  */
174 static void sa1100_enable_ms(struct uart_port *port)
175 {
176 	struct sa1100_port *sport =
177 		container_of(port, struct sa1100_port, port);
178 
179 	mod_timer(&sport->timer, jiffies);
180 
181 	mctrl_gpio_enable_ms(sport->gpios);
182 }
183 
184 static void
185 sa1100_rx_chars(struct sa1100_port *sport)
186 {
187 	unsigned int status, ch, flg;
188 
189 	status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
190 		 UTSR0_TO_SM(UART_GET_UTSR0(sport));
191 	while (status & UTSR1_TO_SM(UTSR1_RNE)) {
192 		ch = UART_GET_CHAR(sport);
193 
194 		sport->port.icount.rx++;
195 
196 		flg = TTY_NORMAL;
197 
198 		/*
199 		 * note that the error handling code is
200 		 * out of the main execution path
201 		 */
202 		if (status & UTSR1_TO_SM(UTSR1_PRE | UTSR1_FRE | UTSR1_ROR)) {
203 			if (status & UTSR1_TO_SM(UTSR1_PRE))
204 				sport->port.icount.parity++;
205 			else if (status & UTSR1_TO_SM(UTSR1_FRE))
206 				sport->port.icount.frame++;
207 			if (status & UTSR1_TO_SM(UTSR1_ROR))
208 				sport->port.icount.overrun++;
209 
210 			status &= sport->port.read_status_mask;
211 
212 			if (status & UTSR1_TO_SM(UTSR1_PRE))
213 				flg = TTY_PARITY;
214 			else if (status & UTSR1_TO_SM(UTSR1_FRE))
215 				flg = TTY_FRAME;
216 
217 #ifdef SUPPORT_SYSRQ
218 			sport->port.sysrq = 0;
219 #endif
220 		}
221 
222 		if (uart_handle_sysrq_char(&sport->port, ch))
223 			goto ignore_char;
224 
225 		uart_insert_char(&sport->port, status, UTSR1_TO_SM(UTSR1_ROR), ch, flg);
226 
227 	ignore_char:
228 		status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
229 			 UTSR0_TO_SM(UART_GET_UTSR0(sport));
230 	}
231 
232 	spin_unlock(&sport->port.lock);
233 	tty_flip_buffer_push(&sport->port.state->port);
234 	spin_lock(&sport->port.lock);
235 }
236 
237 static void sa1100_tx_chars(struct sa1100_port *sport)
238 {
239 	struct circ_buf *xmit = &sport->port.state->xmit;
240 
241 	if (sport->port.x_char) {
242 		UART_PUT_CHAR(sport, sport->port.x_char);
243 		sport->port.icount.tx++;
244 		sport->port.x_char = 0;
245 		return;
246 	}
247 
248 	/*
249 	 * Check the modem control lines before
250 	 * transmitting anything.
251 	 */
252 	sa1100_mctrl_check(sport);
253 
254 	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
255 		sa1100_stop_tx(&sport->port);
256 		return;
257 	}
258 
259 	/*
260 	 * Tried using FIFO (not checking TNF) for fifo fill:
261 	 * still had the '4 bytes repeated' problem.
262 	 */
263 	while (UART_GET_UTSR1(sport) & UTSR1_TNF) {
264 		UART_PUT_CHAR(sport, xmit->buf[xmit->tail]);
265 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
266 		sport->port.icount.tx++;
267 		if (uart_circ_empty(xmit))
268 			break;
269 	}
270 
271 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
272 		uart_write_wakeup(&sport->port);
273 
274 	if (uart_circ_empty(xmit))
275 		sa1100_stop_tx(&sport->port);
276 }
277 
278 static irqreturn_t sa1100_int(int irq, void *dev_id)
279 {
280 	struct sa1100_port *sport = dev_id;
281 	unsigned int status, pass_counter = 0;
282 
283 	spin_lock(&sport->port.lock);
284 	status = UART_GET_UTSR0(sport);
285 	status &= SM_TO_UTSR0(sport->port.read_status_mask) | ~UTSR0_TFS;
286 	do {
287 		if (status & (UTSR0_RFS | UTSR0_RID)) {
288 			/* Clear the receiver idle bit, if set */
289 			if (status & UTSR0_RID)
290 				UART_PUT_UTSR0(sport, UTSR0_RID);
291 			sa1100_rx_chars(sport);
292 		}
293 
294 		/* Clear the relevant break bits */
295 		if (status & (UTSR0_RBB | UTSR0_REB))
296 			UART_PUT_UTSR0(sport, status & (UTSR0_RBB | UTSR0_REB));
297 
298 		if (status & UTSR0_RBB)
299 			sport->port.icount.brk++;
300 
301 		if (status & UTSR0_REB)
302 			uart_handle_break(&sport->port);
303 
304 		if (status & UTSR0_TFS)
305 			sa1100_tx_chars(sport);
306 		if (pass_counter++ > SA1100_ISR_PASS_LIMIT)
307 			break;
308 		status = UART_GET_UTSR0(sport);
309 		status &= SM_TO_UTSR0(sport->port.read_status_mask) |
310 			  ~UTSR0_TFS;
311 	} while (status & (UTSR0_TFS | UTSR0_RFS | UTSR0_RID));
312 	spin_unlock(&sport->port.lock);
313 
314 	return IRQ_HANDLED;
315 }
316 
317 /*
318  * Return TIOCSER_TEMT when transmitter is not busy.
319  */
320 static unsigned int sa1100_tx_empty(struct uart_port *port)
321 {
322 	struct sa1100_port *sport =
323 		container_of(port, struct sa1100_port, port);
324 
325 	return UART_GET_UTSR1(sport) & UTSR1_TBY ? 0 : TIOCSER_TEMT;
326 }
327 
328 static unsigned int sa1100_get_mctrl(struct uart_port *port)
329 {
330 	struct sa1100_port *sport =
331 		container_of(port, struct sa1100_port, port);
332 	int ret = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
333 
334 	mctrl_gpio_get(sport->gpios, &ret);
335 
336 	return ret;
337 }
338 
339 static void sa1100_set_mctrl(struct uart_port *port, unsigned int mctrl)
340 {
341 	struct sa1100_port *sport =
342 		container_of(port, struct sa1100_port, port);
343 
344 	mctrl_gpio_set(sport->gpios, mctrl);
345 }
346 
347 /*
348  * Interrupts always disabled.
349  */
350 static void sa1100_break_ctl(struct uart_port *port, int break_state)
351 {
352 	struct sa1100_port *sport =
353 		container_of(port, struct sa1100_port, port);
354 	unsigned long flags;
355 	unsigned int utcr3;
356 
357 	spin_lock_irqsave(&sport->port.lock, flags);
358 	utcr3 = UART_GET_UTCR3(sport);
359 	if (break_state == -1)
360 		utcr3 |= UTCR3_BRK;
361 	else
362 		utcr3 &= ~UTCR3_BRK;
363 	UART_PUT_UTCR3(sport, utcr3);
364 	spin_unlock_irqrestore(&sport->port.lock, flags);
365 }
366 
367 static int sa1100_startup(struct uart_port *port)
368 {
369 	struct sa1100_port *sport =
370 		container_of(port, struct sa1100_port, port);
371 	int retval;
372 
373 	/*
374 	 * Allocate the IRQ
375 	 */
376 	retval = request_irq(sport->port.irq, sa1100_int, 0,
377 			     "sa11x0-uart", sport);
378 	if (retval)
379 		return retval;
380 
381 	/*
382 	 * Finally, clear and enable interrupts
383 	 */
384 	UART_PUT_UTSR0(sport, -1);
385 	UART_PUT_UTCR3(sport, UTCR3_RXE | UTCR3_TXE | UTCR3_RIE);
386 
387 	/*
388 	 * Enable modem status interrupts
389 	 */
390 	spin_lock_irq(&sport->port.lock);
391 	sa1100_enable_ms(&sport->port);
392 	spin_unlock_irq(&sport->port.lock);
393 
394 	return 0;
395 }
396 
397 static void sa1100_shutdown(struct uart_port *port)
398 {
399 	struct sa1100_port *sport =
400 		container_of(port, struct sa1100_port, port);
401 
402 	/*
403 	 * Stop our timer.
404 	 */
405 	del_timer_sync(&sport->timer);
406 
407 	/*
408 	 * Free the interrupt
409 	 */
410 	free_irq(sport->port.irq, sport);
411 
412 	/*
413 	 * Disable all interrupts, port and break condition.
414 	 */
415 	UART_PUT_UTCR3(sport, 0);
416 }
417 
418 static void
419 sa1100_set_termios(struct uart_port *port, struct ktermios *termios,
420 		   struct ktermios *old)
421 {
422 	struct sa1100_port *sport =
423 		container_of(port, struct sa1100_port, port);
424 	unsigned long flags;
425 	unsigned int utcr0, old_utcr3, baud, quot;
426 	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
427 
428 	/*
429 	 * We only support CS7 and CS8.
430 	 */
431 	while ((termios->c_cflag & CSIZE) != CS7 &&
432 	       (termios->c_cflag & CSIZE) != CS8) {
433 		termios->c_cflag &= ~CSIZE;
434 		termios->c_cflag |= old_csize;
435 		old_csize = CS8;
436 	}
437 
438 	if ((termios->c_cflag & CSIZE) == CS8)
439 		utcr0 = UTCR0_DSS;
440 	else
441 		utcr0 = 0;
442 
443 	if (termios->c_cflag & CSTOPB)
444 		utcr0 |= UTCR0_SBS;
445 	if (termios->c_cflag & PARENB) {
446 		utcr0 |= UTCR0_PE;
447 		if (!(termios->c_cflag & PARODD))
448 			utcr0 |= UTCR0_OES;
449 	}
450 
451 	/*
452 	 * Ask the core to calculate the divisor for us.
453 	 */
454 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
455 	quot = uart_get_divisor(port, baud);
456 
457 	spin_lock_irqsave(&sport->port.lock, flags);
458 
459 	sport->port.read_status_mask &= UTSR0_TO_SM(UTSR0_TFS);
460 	sport->port.read_status_mask |= UTSR1_TO_SM(UTSR1_ROR);
461 	if (termios->c_iflag & INPCK)
462 		sport->port.read_status_mask |=
463 				UTSR1_TO_SM(UTSR1_FRE | UTSR1_PRE);
464 	if (termios->c_iflag & (BRKINT | PARMRK))
465 		sport->port.read_status_mask |=
466 				UTSR0_TO_SM(UTSR0_RBB | UTSR0_REB);
467 
468 	/*
469 	 * Characters to ignore
470 	 */
471 	sport->port.ignore_status_mask = 0;
472 	if (termios->c_iflag & IGNPAR)
473 		sport->port.ignore_status_mask |=
474 				UTSR1_TO_SM(UTSR1_FRE | UTSR1_PRE);
475 	if (termios->c_iflag & IGNBRK) {
476 		sport->port.ignore_status_mask |=
477 				UTSR0_TO_SM(UTSR0_RBB | UTSR0_REB);
478 		/*
479 		 * If we're ignoring parity and break indicators,
480 		 * ignore overruns too (for real raw support).
481 		 */
482 		if (termios->c_iflag & IGNPAR)
483 			sport->port.ignore_status_mask |=
484 				UTSR1_TO_SM(UTSR1_ROR);
485 	}
486 
487 	del_timer_sync(&sport->timer);
488 
489 	/*
490 	 * Update the per-port timeout.
491 	 */
492 	uart_update_timeout(port, termios->c_cflag, baud);
493 
494 	/*
495 	 * disable interrupts and drain transmitter
496 	 */
497 	old_utcr3 = UART_GET_UTCR3(sport);
498 	UART_PUT_UTCR3(sport, old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE));
499 
500 	while (UART_GET_UTSR1(sport) & UTSR1_TBY)
501 		barrier();
502 
503 	/* then, disable everything */
504 	UART_PUT_UTCR3(sport, 0);
505 
506 	/* set the parity, stop bits and data size */
507 	UART_PUT_UTCR0(sport, utcr0);
508 
509 	/* set the baud rate */
510 	quot -= 1;
511 	UART_PUT_UTCR1(sport, ((quot & 0xf00) >> 8));
512 	UART_PUT_UTCR2(sport, (quot & 0xff));
513 
514 	UART_PUT_UTSR0(sport, -1);
515 
516 	UART_PUT_UTCR3(sport, old_utcr3);
517 
518 	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
519 		sa1100_enable_ms(&sport->port);
520 
521 	spin_unlock_irqrestore(&sport->port.lock, flags);
522 }
523 
524 static const char *sa1100_type(struct uart_port *port)
525 {
526 	struct sa1100_port *sport =
527 		container_of(port, struct sa1100_port, port);
528 
529 	return sport->port.type == PORT_SA1100 ? "SA1100" : NULL;
530 }
531 
532 /*
533  * Release the memory region(s) being used by 'port'.
534  */
535 static void sa1100_release_port(struct uart_port *port)
536 {
537 	struct sa1100_port *sport =
538 		container_of(port, struct sa1100_port, port);
539 
540 	release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
541 }
542 
543 /*
544  * Request the memory region(s) being used by 'port'.
545  */
546 static int sa1100_request_port(struct uart_port *port)
547 {
548 	struct sa1100_port *sport =
549 		container_of(port, struct sa1100_port, port);
550 
551 	return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
552 			"sa11x0-uart") != NULL ? 0 : -EBUSY;
553 }
554 
555 /*
556  * Configure/autoconfigure the port.
557  */
558 static void sa1100_config_port(struct uart_port *port, int flags)
559 {
560 	struct sa1100_port *sport =
561 		container_of(port, struct sa1100_port, port);
562 
563 	if (flags & UART_CONFIG_TYPE &&
564 	    sa1100_request_port(&sport->port) == 0)
565 		sport->port.type = PORT_SA1100;
566 }
567 
568 /*
569  * Verify the new serial_struct (for TIOCSSERIAL).
570  * The only change we allow are to the flags and type, and
571  * even then only between PORT_SA1100 and PORT_UNKNOWN
572  */
573 static int
574 sa1100_verify_port(struct uart_port *port, struct serial_struct *ser)
575 {
576 	struct sa1100_port *sport =
577 		container_of(port, struct sa1100_port, port);
578 	int ret = 0;
579 
580 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_SA1100)
581 		ret = -EINVAL;
582 	if (sport->port.irq != ser->irq)
583 		ret = -EINVAL;
584 	if (ser->io_type != SERIAL_IO_MEM)
585 		ret = -EINVAL;
586 	if (sport->port.uartclk / 16 != ser->baud_base)
587 		ret = -EINVAL;
588 	if ((void *)sport->port.mapbase != ser->iomem_base)
589 		ret = -EINVAL;
590 	if (sport->port.iobase != ser->port)
591 		ret = -EINVAL;
592 	if (ser->hub6 != 0)
593 		ret = -EINVAL;
594 	return ret;
595 }
596 
597 static struct uart_ops sa1100_pops = {
598 	.tx_empty	= sa1100_tx_empty,
599 	.set_mctrl	= sa1100_set_mctrl,
600 	.get_mctrl	= sa1100_get_mctrl,
601 	.stop_tx	= sa1100_stop_tx,
602 	.start_tx	= sa1100_start_tx,
603 	.stop_rx	= sa1100_stop_rx,
604 	.enable_ms	= sa1100_enable_ms,
605 	.break_ctl	= sa1100_break_ctl,
606 	.startup	= sa1100_startup,
607 	.shutdown	= sa1100_shutdown,
608 	.set_termios	= sa1100_set_termios,
609 	.type		= sa1100_type,
610 	.release_port	= sa1100_release_port,
611 	.request_port	= sa1100_request_port,
612 	.config_port	= sa1100_config_port,
613 	.verify_port	= sa1100_verify_port,
614 };
615 
616 static struct sa1100_port sa1100_ports[NR_PORTS];
617 
618 /*
619  * Setup the SA1100 serial ports.  Note that we don't include the IrDA
620  * port here since we have our own SIR/FIR driver (see drivers/net/irda)
621  *
622  * Note also that we support "console=ttySAx" where "x" is either 0 or 1.
623  * Which serial port this ends up being depends on the machine you're
624  * running this kernel on.  I'm not convinced that this is a good idea,
625  * but that's the way it traditionally works.
626  *
627  * Note that NanoEngine UART3 becomes UART2, and UART2 is no longer
628  * used here.
629  */
630 static void __init sa1100_init_ports(void)
631 {
632 	static int first = 1;
633 	int i;
634 
635 	if (!first)
636 		return;
637 	first = 0;
638 
639 	for (i = 0; i < NR_PORTS; i++) {
640 		sa1100_ports[i].port.uartclk   = 3686400;
641 		sa1100_ports[i].port.ops       = &sa1100_pops;
642 		sa1100_ports[i].port.fifosize  = 8;
643 		sa1100_ports[i].port.line      = i;
644 		sa1100_ports[i].port.iotype    = UPIO_MEM;
645 		timer_setup(&sa1100_ports[i].timer, sa1100_timeout, 0);
646 	}
647 
648 	/*
649 	 * make transmit lines outputs, so that when the port
650 	 * is closed, the output is in the MARK state.
651 	 */
652 	PPDR |= PPC_TXD1 | PPC_TXD3;
653 	PPSR |= PPC_TXD1 | PPC_TXD3;
654 }
655 
656 void sa1100_register_uart_fns(struct sa1100_port_fns *fns)
657 {
658 	if (fns->get_mctrl)
659 		sa1100_pops.get_mctrl = fns->get_mctrl;
660 	if (fns->set_mctrl)
661 		sa1100_pops.set_mctrl = fns->set_mctrl;
662 
663 	sa1100_pops.pm       = fns->pm;
664 	/*
665 	 * FIXME: fns->set_wake is unused - this should be called from
666 	 * the suspend() callback if device_may_wakeup(dev)) is set.
667 	 */
668 }
669 
670 void __init sa1100_register_uart(int idx, int port)
671 {
672 	if (idx >= NR_PORTS) {
673 		printk(KERN_ERR "%s: bad index number %d\n", __func__, idx);
674 		return;
675 	}
676 
677 	switch (port) {
678 	case 1:
679 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser1UTCR0;
680 		sa1100_ports[idx].port.mapbase = _Ser1UTCR0;
681 		sa1100_ports[idx].port.irq     = IRQ_Ser1UART;
682 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
683 		break;
684 
685 	case 2:
686 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser2UTCR0;
687 		sa1100_ports[idx].port.mapbase = _Ser2UTCR0;
688 		sa1100_ports[idx].port.irq     = IRQ_Ser2ICP;
689 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
690 		break;
691 
692 	case 3:
693 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser3UTCR0;
694 		sa1100_ports[idx].port.mapbase = _Ser3UTCR0;
695 		sa1100_ports[idx].port.irq     = IRQ_Ser3UART;
696 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
697 		break;
698 
699 	default:
700 		printk(KERN_ERR "%s: bad port number %d\n", __func__, port);
701 	}
702 }
703 
704 
705 #ifdef CONFIG_SERIAL_SA1100_CONSOLE
706 static void sa1100_console_putchar(struct uart_port *port, int ch)
707 {
708 	struct sa1100_port *sport =
709 		container_of(port, struct sa1100_port, port);
710 
711 	while (!(UART_GET_UTSR1(sport) & UTSR1_TNF))
712 		barrier();
713 	UART_PUT_CHAR(sport, ch);
714 }
715 
716 /*
717  * Interrupts are disabled on entering
718  */
719 static void
720 sa1100_console_write(struct console *co, const char *s, unsigned int count)
721 {
722 	struct sa1100_port *sport = &sa1100_ports[co->index];
723 	unsigned int old_utcr3, status;
724 
725 	/*
726 	 *	First, save UTCR3 and then disable interrupts
727 	 */
728 	old_utcr3 = UART_GET_UTCR3(sport);
729 	UART_PUT_UTCR3(sport, (old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE)) |
730 				UTCR3_TXE);
731 
732 	uart_console_write(&sport->port, s, count, sa1100_console_putchar);
733 
734 	/*
735 	 *	Finally, wait for transmitter to become empty
736 	 *	and restore UTCR3
737 	 */
738 	do {
739 		status = UART_GET_UTSR1(sport);
740 	} while (status & UTSR1_TBY);
741 	UART_PUT_UTCR3(sport, old_utcr3);
742 }
743 
744 /*
745  * If the port was already initialised (eg, by a boot loader),
746  * try to determine the current setup.
747  */
748 static void __init
749 sa1100_console_get_options(struct sa1100_port *sport, int *baud,
750 			   int *parity, int *bits)
751 {
752 	unsigned int utcr3;
753 
754 	utcr3 = UART_GET_UTCR3(sport) & (UTCR3_RXE | UTCR3_TXE);
755 	if (utcr3 == (UTCR3_RXE | UTCR3_TXE)) {
756 		/* ok, the port was enabled */
757 		unsigned int utcr0, quot;
758 
759 		utcr0 = UART_GET_UTCR0(sport);
760 
761 		*parity = 'n';
762 		if (utcr0 & UTCR0_PE) {
763 			if (utcr0 & UTCR0_OES)
764 				*parity = 'e';
765 			else
766 				*parity = 'o';
767 		}
768 
769 		if (utcr0 & UTCR0_DSS)
770 			*bits = 8;
771 		else
772 			*bits = 7;
773 
774 		quot = UART_GET_UTCR2(sport) | UART_GET_UTCR1(sport) << 8;
775 		quot &= 0xfff;
776 		*baud = sport->port.uartclk / (16 * (quot + 1));
777 	}
778 }
779 
780 static int __init
781 sa1100_console_setup(struct console *co, char *options)
782 {
783 	struct sa1100_port *sport;
784 	int baud = 9600;
785 	int bits = 8;
786 	int parity = 'n';
787 	int flow = 'n';
788 
789 	/*
790 	 * Check whether an invalid uart number has been specified, and
791 	 * if so, search for the first available port that does have
792 	 * console support.
793 	 */
794 	if (co->index == -1 || co->index >= NR_PORTS)
795 		co->index = 0;
796 	sport = &sa1100_ports[co->index];
797 
798 	if (options)
799 		uart_parse_options(options, &baud, &parity, &bits, &flow);
800 	else
801 		sa1100_console_get_options(sport, &baud, &parity, &bits);
802 
803 	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
804 }
805 
806 static struct uart_driver sa1100_reg;
807 static struct console sa1100_console = {
808 	.name		= "ttySA",
809 	.write		= sa1100_console_write,
810 	.device		= uart_console_device,
811 	.setup		= sa1100_console_setup,
812 	.flags		= CON_PRINTBUFFER,
813 	.index		= -1,
814 	.data		= &sa1100_reg,
815 };
816 
817 static int __init sa1100_rs_console_init(void)
818 {
819 	sa1100_init_ports();
820 	register_console(&sa1100_console);
821 	return 0;
822 }
823 console_initcall(sa1100_rs_console_init);
824 
825 #define SA1100_CONSOLE	&sa1100_console
826 #else
827 #define SA1100_CONSOLE	NULL
828 #endif
829 
830 static struct uart_driver sa1100_reg = {
831 	.owner			= THIS_MODULE,
832 	.driver_name		= "ttySA",
833 	.dev_name		= "ttySA",
834 	.major			= SERIAL_SA1100_MAJOR,
835 	.minor			= MINOR_START,
836 	.nr			= NR_PORTS,
837 	.cons			= SA1100_CONSOLE,
838 };
839 
840 static int sa1100_serial_suspend(struct platform_device *dev, pm_message_t state)
841 {
842 	struct sa1100_port *sport = platform_get_drvdata(dev);
843 
844 	if (sport)
845 		uart_suspend_port(&sa1100_reg, &sport->port);
846 
847 	return 0;
848 }
849 
850 static int sa1100_serial_resume(struct platform_device *dev)
851 {
852 	struct sa1100_port *sport = platform_get_drvdata(dev);
853 
854 	if (sport)
855 		uart_resume_port(&sa1100_reg, &sport->port);
856 
857 	return 0;
858 }
859 
860 static int sa1100_serial_add_one_port(struct sa1100_port *sport, struct platform_device *dev)
861 {
862 	sport->port.dev = &dev->dev;
863 
864 	// mctrl_gpio_init() requires that the GPIO driver supports interrupts,
865 	// but we need to support GPIO drivers for hardware that has no such
866 	// interrupts.  Use mctrl_gpio_init_noauto() instead.
867 	sport->gpios = mctrl_gpio_init_noauto(sport->port.dev, 0);
868 	if (IS_ERR(sport->gpios)) {
869 		int err = PTR_ERR(sport->gpios);
870 
871 		dev_err(sport->port.dev, "failed to get mctrl gpios: %d\n",
872 			err);
873 
874 		if (err == -EPROBE_DEFER)
875 			return err;
876 
877 		sport->gpios = NULL;
878 	}
879 
880 	platform_set_drvdata(dev, sport);
881 
882 	return uart_add_one_port(&sa1100_reg, &sport->port);
883 }
884 
885 static int sa1100_serial_probe(struct platform_device *dev)
886 {
887 	struct resource *res = dev->resource;
888 	int i;
889 
890 	for (i = 0; i < dev->num_resources; i++, res++)
891 		if (res->flags & IORESOURCE_MEM)
892 			break;
893 
894 	if (i < dev->num_resources) {
895 		for (i = 0; i < NR_PORTS; i++) {
896 			if (sa1100_ports[i].port.mapbase != res->start)
897 				continue;
898 
899 			sa1100_serial_add_one_port(&sa1100_ports[i], dev);
900 			break;
901 		}
902 	}
903 
904 	return 0;
905 }
906 
907 static int sa1100_serial_remove(struct platform_device *pdev)
908 {
909 	struct sa1100_port *sport = platform_get_drvdata(pdev);
910 
911 	if (sport)
912 		uart_remove_one_port(&sa1100_reg, &sport->port);
913 
914 	return 0;
915 }
916 
917 static struct platform_driver sa11x0_serial_driver = {
918 	.probe		= sa1100_serial_probe,
919 	.remove		= sa1100_serial_remove,
920 	.suspend	= sa1100_serial_suspend,
921 	.resume		= sa1100_serial_resume,
922 	.driver		= {
923 		.name	= "sa11x0-uart",
924 	},
925 };
926 
927 static int __init sa1100_serial_init(void)
928 {
929 	int ret;
930 
931 	printk(KERN_INFO "Serial: SA11x0 driver\n");
932 
933 	sa1100_init_ports();
934 
935 	ret = uart_register_driver(&sa1100_reg);
936 	if (ret == 0) {
937 		ret = platform_driver_register(&sa11x0_serial_driver);
938 		if (ret)
939 			uart_unregister_driver(&sa1100_reg);
940 	}
941 	return ret;
942 }
943 
944 static void __exit sa1100_serial_exit(void)
945 {
946 	platform_driver_unregister(&sa11x0_serial_driver);
947 	uart_unregister_driver(&sa1100_reg);
948 }
949 
950 module_init(sa1100_serial_init);
951 module_exit(sa1100_serial_exit);
952 
953 MODULE_AUTHOR("Deep Blue Solutions Ltd");
954 MODULE_DESCRIPTION("SA1100 generic serial port driver");
955 MODULE_LICENSE("GPL");
956 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_SA1100_MAJOR);
957 MODULE_ALIAS("platform:sa11x0-uart");
958