xref: /openbmc/linux/drivers/tty/serial/sa1100.c (revision 0d3b051a)
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 #include <linux/module.h>
11 #include <linux/ioport.h>
12 #include <linux/init.h>
13 #include <linux/console.h>
14 #include <linux/sysrq.h>
15 #include <linux/platform_data/sa11x0-serial.h>
16 #include <linux/platform_device.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/serial_core.h>
20 #include <linux/serial.h>
21 #include <linux/io.h>
22 
23 #include <asm/irq.h>
24 #include <mach/hardware.h>
25 #include <mach/irqs.h>
26 
27 #include "serial_mctrl_gpio.h"
28 
29 /* We've been assigned a range on the "Low-density serial ports" major */
30 #define SERIAL_SA1100_MAJOR	204
31 #define MINOR_START		5
32 
33 #define NR_PORTS		3
34 
35 #define SA1100_ISR_PASS_LIMIT	256
36 
37 /*
38  * Convert from ignore_status_mask or read_status_mask to UTSR[01]
39  */
40 #define SM_TO_UTSR0(x)	((x) & 0xff)
41 #define SM_TO_UTSR1(x)	((x) >> 8)
42 #define UTSR0_TO_SM(x)	((x))
43 #define UTSR1_TO_SM(x)	((x) << 8)
44 
45 #define UART_GET_UTCR0(sport)	__raw_readl((sport)->port.membase + UTCR0)
46 #define UART_GET_UTCR1(sport)	__raw_readl((sport)->port.membase + UTCR1)
47 #define UART_GET_UTCR2(sport)	__raw_readl((sport)->port.membase + UTCR2)
48 #define UART_GET_UTCR3(sport)	__raw_readl((sport)->port.membase + UTCR3)
49 #define UART_GET_UTSR0(sport)	__raw_readl((sport)->port.membase + UTSR0)
50 #define UART_GET_UTSR1(sport)	__raw_readl((sport)->port.membase + UTSR1)
51 #define UART_GET_CHAR(sport)	__raw_readl((sport)->port.membase + UTDR)
52 
53 #define UART_PUT_UTCR0(sport,v)	__raw_writel((v),(sport)->port.membase + UTCR0)
54 #define UART_PUT_UTCR1(sport,v)	__raw_writel((v),(sport)->port.membase + UTCR1)
55 #define UART_PUT_UTCR2(sport,v)	__raw_writel((v),(sport)->port.membase + UTCR2)
56 #define UART_PUT_UTCR3(sport,v)	__raw_writel((v),(sport)->port.membase + UTCR3)
57 #define UART_PUT_UTSR0(sport,v)	__raw_writel((v),(sport)->port.membase + UTSR0)
58 #define UART_PUT_UTSR1(sport,v)	__raw_writel((v),(sport)->port.membase + UTSR1)
59 #define UART_PUT_CHAR(sport,v)	__raw_writel((v),(sport)->port.membase + UTDR)
60 
61 /*
62  * This is the size of our serial port register set.
63  */
64 #define UART_PORT_SIZE	0x24
65 
66 /*
67  * This determines how often we check the modem status signals
68  * for any change.  They generally aren't connected to an IRQ
69  * so we have to poll them.  We also check immediately before
70  * filling the TX fifo incase CTS has been dropped.
71  */
72 #define MCTRL_TIMEOUT	(250*HZ/1000)
73 
74 struct sa1100_port {
75 	struct uart_port	port;
76 	struct timer_list	timer;
77 	unsigned int		old_status;
78 	struct mctrl_gpios	*gpios;
79 };
80 
81 /*
82  * Handle any change of modem status signal since we were last called.
83  */
84 static void sa1100_mctrl_check(struct sa1100_port *sport)
85 {
86 	unsigned int status, changed;
87 
88 	status = sport->port.ops->get_mctrl(&sport->port);
89 	changed = status ^ sport->old_status;
90 
91 	if (changed == 0)
92 		return;
93 
94 	sport->old_status = status;
95 
96 	if (changed & TIOCM_RI)
97 		sport->port.icount.rng++;
98 	if (changed & TIOCM_DSR)
99 		sport->port.icount.dsr++;
100 	if (changed & TIOCM_CAR)
101 		uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
102 	if (changed & TIOCM_CTS)
103 		uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
104 
105 	wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
106 }
107 
108 /*
109  * This is our per-port timeout handler, for checking the
110  * modem status signals.
111  */
112 static void sa1100_timeout(struct timer_list *t)
113 {
114 	struct sa1100_port *sport = from_timer(sport, t, timer);
115 	unsigned long flags;
116 
117 	if (sport->port.state) {
118 		spin_lock_irqsave(&sport->port.lock, flags);
119 		sa1100_mctrl_check(sport);
120 		spin_unlock_irqrestore(&sport->port.lock, flags);
121 
122 		mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
123 	}
124 }
125 
126 /*
127  * interrupts disabled on entry
128  */
129 static void sa1100_stop_tx(struct uart_port *port)
130 {
131 	struct sa1100_port *sport =
132 		container_of(port, struct sa1100_port, port);
133 	u32 utcr3;
134 
135 	utcr3 = UART_GET_UTCR3(sport);
136 	UART_PUT_UTCR3(sport, utcr3 & ~UTCR3_TIE);
137 	sport->port.read_status_mask &= ~UTSR0_TO_SM(UTSR0_TFS);
138 }
139 
140 /*
141  * port locked and interrupts disabled
142  */
143 static void sa1100_start_tx(struct uart_port *port)
144 {
145 	struct sa1100_port *sport =
146 		container_of(port, struct sa1100_port, port);
147 	u32 utcr3;
148 
149 	utcr3 = UART_GET_UTCR3(sport);
150 	sport->port.read_status_mask |= UTSR0_TO_SM(UTSR0_TFS);
151 	UART_PUT_UTCR3(sport, utcr3 | UTCR3_TIE);
152 }
153 
154 /*
155  * Interrupts enabled
156  */
157 static void sa1100_stop_rx(struct uart_port *port)
158 {
159 	struct sa1100_port *sport =
160 		container_of(port, struct sa1100_port, port);
161 	u32 utcr3;
162 
163 	utcr3 = UART_GET_UTCR3(sport);
164 	UART_PUT_UTCR3(sport, utcr3 & ~UTCR3_RIE);
165 }
166 
167 /*
168  * Set the modem control timer to fire immediately.
169  */
170 static void sa1100_enable_ms(struct uart_port *port)
171 {
172 	struct sa1100_port *sport =
173 		container_of(port, struct sa1100_port, port);
174 
175 	mod_timer(&sport->timer, jiffies);
176 
177 	mctrl_gpio_enable_ms(sport->gpios);
178 }
179 
180 static void
181 sa1100_rx_chars(struct sa1100_port *sport)
182 {
183 	unsigned int status, ch, flg;
184 
185 	status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
186 		 UTSR0_TO_SM(UART_GET_UTSR0(sport));
187 	while (status & UTSR1_TO_SM(UTSR1_RNE)) {
188 		ch = UART_GET_CHAR(sport);
189 
190 		sport->port.icount.rx++;
191 
192 		flg = TTY_NORMAL;
193 
194 		/*
195 		 * note that the error handling code is
196 		 * out of the main execution path
197 		 */
198 		if (status & UTSR1_TO_SM(UTSR1_PRE | UTSR1_FRE | UTSR1_ROR)) {
199 			if (status & UTSR1_TO_SM(UTSR1_PRE))
200 				sport->port.icount.parity++;
201 			else if (status & UTSR1_TO_SM(UTSR1_FRE))
202 				sport->port.icount.frame++;
203 			if (status & UTSR1_TO_SM(UTSR1_ROR))
204 				sport->port.icount.overrun++;
205 
206 			status &= sport->port.read_status_mask;
207 
208 			if (status & UTSR1_TO_SM(UTSR1_PRE))
209 				flg = TTY_PARITY;
210 			else if (status & UTSR1_TO_SM(UTSR1_FRE))
211 				flg = TTY_FRAME;
212 
213 			sport->port.sysrq = 0;
214 		}
215 
216 		if (uart_handle_sysrq_char(&sport->port, ch))
217 			goto ignore_char;
218 
219 		uart_insert_char(&sport->port, status, UTSR1_TO_SM(UTSR1_ROR), ch, flg);
220 
221 	ignore_char:
222 		status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
223 			 UTSR0_TO_SM(UART_GET_UTSR0(sport));
224 	}
225 
226 	spin_unlock(&sport->port.lock);
227 	tty_flip_buffer_push(&sport->port.state->port);
228 	spin_lock(&sport->port.lock);
229 }
230 
231 static void sa1100_tx_chars(struct sa1100_port *sport)
232 {
233 	struct circ_buf *xmit = &sport->port.state->xmit;
234 
235 	if (sport->port.x_char) {
236 		UART_PUT_CHAR(sport, sport->port.x_char);
237 		sport->port.icount.tx++;
238 		sport->port.x_char = 0;
239 		return;
240 	}
241 
242 	/*
243 	 * Check the modem control lines before
244 	 * transmitting anything.
245 	 */
246 	sa1100_mctrl_check(sport);
247 
248 	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
249 		sa1100_stop_tx(&sport->port);
250 		return;
251 	}
252 
253 	/*
254 	 * Tried using FIFO (not checking TNF) for fifo fill:
255 	 * still had the '4 bytes repeated' problem.
256 	 */
257 	while (UART_GET_UTSR1(sport) & UTSR1_TNF) {
258 		UART_PUT_CHAR(sport, xmit->buf[xmit->tail]);
259 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
260 		sport->port.icount.tx++;
261 		if (uart_circ_empty(xmit))
262 			break;
263 	}
264 
265 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
266 		uart_write_wakeup(&sport->port);
267 
268 	if (uart_circ_empty(xmit))
269 		sa1100_stop_tx(&sport->port);
270 }
271 
272 static irqreturn_t sa1100_int(int irq, void *dev_id)
273 {
274 	struct sa1100_port *sport = dev_id;
275 	unsigned int status, pass_counter = 0;
276 
277 	spin_lock(&sport->port.lock);
278 	status = UART_GET_UTSR0(sport);
279 	status &= SM_TO_UTSR0(sport->port.read_status_mask) | ~UTSR0_TFS;
280 	do {
281 		if (status & (UTSR0_RFS | UTSR0_RID)) {
282 			/* Clear the receiver idle bit, if set */
283 			if (status & UTSR0_RID)
284 				UART_PUT_UTSR0(sport, UTSR0_RID);
285 			sa1100_rx_chars(sport);
286 		}
287 
288 		/* Clear the relevant break bits */
289 		if (status & (UTSR0_RBB | UTSR0_REB))
290 			UART_PUT_UTSR0(sport, status & (UTSR0_RBB | UTSR0_REB));
291 
292 		if (status & UTSR0_RBB)
293 			sport->port.icount.brk++;
294 
295 		if (status & UTSR0_REB)
296 			uart_handle_break(&sport->port);
297 
298 		if (status & UTSR0_TFS)
299 			sa1100_tx_chars(sport);
300 		if (pass_counter++ > SA1100_ISR_PASS_LIMIT)
301 			break;
302 		status = UART_GET_UTSR0(sport);
303 		status &= SM_TO_UTSR0(sport->port.read_status_mask) |
304 			  ~UTSR0_TFS;
305 	} while (status & (UTSR0_TFS | UTSR0_RFS | UTSR0_RID));
306 	spin_unlock(&sport->port.lock);
307 
308 	return IRQ_HANDLED;
309 }
310 
311 /*
312  * Return TIOCSER_TEMT when transmitter is not busy.
313  */
314 static unsigned int sa1100_tx_empty(struct uart_port *port)
315 {
316 	struct sa1100_port *sport =
317 		container_of(port, struct sa1100_port, port);
318 
319 	return UART_GET_UTSR1(sport) & UTSR1_TBY ? 0 : TIOCSER_TEMT;
320 }
321 
322 static unsigned int sa1100_get_mctrl(struct uart_port *port)
323 {
324 	struct sa1100_port *sport =
325 		container_of(port, struct sa1100_port, port);
326 	int ret = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
327 
328 	mctrl_gpio_get(sport->gpios, &ret);
329 
330 	return ret;
331 }
332 
333 static void sa1100_set_mctrl(struct uart_port *port, unsigned int mctrl)
334 {
335 	struct sa1100_port *sport =
336 		container_of(port, struct sa1100_port, port);
337 
338 	mctrl_gpio_set(sport->gpios, mctrl);
339 }
340 
341 /*
342  * Interrupts always disabled.
343  */
344 static void sa1100_break_ctl(struct uart_port *port, int break_state)
345 {
346 	struct sa1100_port *sport =
347 		container_of(port, struct sa1100_port, port);
348 	unsigned long flags;
349 	unsigned int utcr3;
350 
351 	spin_lock_irqsave(&sport->port.lock, flags);
352 	utcr3 = UART_GET_UTCR3(sport);
353 	if (break_state == -1)
354 		utcr3 |= UTCR3_BRK;
355 	else
356 		utcr3 &= ~UTCR3_BRK;
357 	UART_PUT_UTCR3(sport, utcr3);
358 	spin_unlock_irqrestore(&sport->port.lock, flags);
359 }
360 
361 static int sa1100_startup(struct uart_port *port)
362 {
363 	struct sa1100_port *sport =
364 		container_of(port, struct sa1100_port, port);
365 	int retval;
366 
367 	/*
368 	 * Allocate the IRQ
369 	 */
370 	retval = request_irq(sport->port.irq, sa1100_int, 0,
371 			     "sa11x0-uart", sport);
372 	if (retval)
373 		return retval;
374 
375 	/*
376 	 * Finally, clear and enable interrupts
377 	 */
378 	UART_PUT_UTSR0(sport, -1);
379 	UART_PUT_UTCR3(sport, UTCR3_RXE | UTCR3_TXE | UTCR3_RIE);
380 
381 	/*
382 	 * Enable modem status interrupts
383 	 */
384 	spin_lock_irq(&sport->port.lock);
385 	sa1100_enable_ms(&sport->port);
386 	spin_unlock_irq(&sport->port.lock);
387 
388 	return 0;
389 }
390 
391 static void sa1100_shutdown(struct uart_port *port)
392 {
393 	struct sa1100_port *sport =
394 		container_of(port, struct sa1100_port, port);
395 
396 	/*
397 	 * Stop our timer.
398 	 */
399 	del_timer_sync(&sport->timer);
400 
401 	/*
402 	 * Free the interrupt
403 	 */
404 	free_irq(sport->port.irq, sport);
405 
406 	/*
407 	 * Disable all interrupts, port and break condition.
408 	 */
409 	UART_PUT_UTCR3(sport, 0);
410 }
411 
412 static void
413 sa1100_set_termios(struct uart_port *port, struct ktermios *termios,
414 		   struct ktermios *old)
415 {
416 	struct sa1100_port *sport =
417 		container_of(port, struct sa1100_port, port);
418 	unsigned long flags;
419 	unsigned int utcr0, old_utcr3, baud, quot;
420 	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
421 
422 	/*
423 	 * We only support CS7 and CS8.
424 	 */
425 	while ((termios->c_cflag & CSIZE) != CS7 &&
426 	       (termios->c_cflag & CSIZE) != CS8) {
427 		termios->c_cflag &= ~CSIZE;
428 		termios->c_cflag |= old_csize;
429 		old_csize = CS8;
430 	}
431 
432 	if ((termios->c_cflag & CSIZE) == CS8)
433 		utcr0 = UTCR0_DSS;
434 	else
435 		utcr0 = 0;
436 
437 	if (termios->c_cflag & CSTOPB)
438 		utcr0 |= UTCR0_SBS;
439 	if (termios->c_cflag & PARENB) {
440 		utcr0 |= UTCR0_PE;
441 		if (!(termios->c_cflag & PARODD))
442 			utcr0 |= UTCR0_OES;
443 	}
444 
445 	/*
446 	 * Ask the core to calculate the divisor for us.
447 	 */
448 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
449 	quot = uart_get_divisor(port, baud);
450 
451 	spin_lock_irqsave(&sport->port.lock, flags);
452 
453 	sport->port.read_status_mask &= UTSR0_TO_SM(UTSR0_TFS);
454 	sport->port.read_status_mask |= UTSR1_TO_SM(UTSR1_ROR);
455 	if (termios->c_iflag & INPCK)
456 		sport->port.read_status_mask |=
457 				UTSR1_TO_SM(UTSR1_FRE | UTSR1_PRE);
458 	if (termios->c_iflag & (BRKINT | PARMRK))
459 		sport->port.read_status_mask |=
460 				UTSR0_TO_SM(UTSR0_RBB | UTSR0_REB);
461 
462 	/*
463 	 * Characters to ignore
464 	 */
465 	sport->port.ignore_status_mask = 0;
466 	if (termios->c_iflag & IGNPAR)
467 		sport->port.ignore_status_mask |=
468 				UTSR1_TO_SM(UTSR1_FRE | UTSR1_PRE);
469 	if (termios->c_iflag & IGNBRK) {
470 		sport->port.ignore_status_mask |=
471 				UTSR0_TO_SM(UTSR0_RBB | UTSR0_REB);
472 		/*
473 		 * If we're ignoring parity and break indicators,
474 		 * ignore overruns too (for real raw support).
475 		 */
476 		if (termios->c_iflag & IGNPAR)
477 			sport->port.ignore_status_mask |=
478 				UTSR1_TO_SM(UTSR1_ROR);
479 	}
480 
481 	del_timer_sync(&sport->timer);
482 
483 	/*
484 	 * Update the per-port timeout.
485 	 */
486 	uart_update_timeout(port, termios->c_cflag, baud);
487 
488 	/*
489 	 * disable interrupts and drain transmitter
490 	 */
491 	old_utcr3 = UART_GET_UTCR3(sport);
492 	UART_PUT_UTCR3(sport, old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE));
493 
494 	while (UART_GET_UTSR1(sport) & UTSR1_TBY)
495 		barrier();
496 
497 	/* then, disable everything */
498 	UART_PUT_UTCR3(sport, 0);
499 
500 	/* set the parity, stop bits and data size */
501 	UART_PUT_UTCR0(sport, utcr0);
502 
503 	/* set the baud rate */
504 	quot -= 1;
505 	UART_PUT_UTCR1(sport, ((quot & 0xf00) >> 8));
506 	UART_PUT_UTCR2(sport, (quot & 0xff));
507 
508 	UART_PUT_UTSR0(sport, -1);
509 
510 	UART_PUT_UTCR3(sport, old_utcr3);
511 
512 	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
513 		sa1100_enable_ms(&sport->port);
514 
515 	spin_unlock_irqrestore(&sport->port.lock, flags);
516 }
517 
518 static const char *sa1100_type(struct uart_port *port)
519 {
520 	struct sa1100_port *sport =
521 		container_of(port, struct sa1100_port, port);
522 
523 	return sport->port.type == PORT_SA1100 ? "SA1100" : NULL;
524 }
525 
526 /*
527  * Release the memory region(s) being used by 'port'.
528  */
529 static void sa1100_release_port(struct uart_port *port)
530 {
531 	struct sa1100_port *sport =
532 		container_of(port, struct sa1100_port, port);
533 
534 	release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
535 }
536 
537 /*
538  * Request the memory region(s) being used by 'port'.
539  */
540 static int sa1100_request_port(struct uart_port *port)
541 {
542 	struct sa1100_port *sport =
543 		container_of(port, struct sa1100_port, port);
544 
545 	return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
546 			"sa11x0-uart") != NULL ? 0 : -EBUSY;
547 }
548 
549 /*
550  * Configure/autoconfigure the port.
551  */
552 static void sa1100_config_port(struct uart_port *port, int flags)
553 {
554 	struct sa1100_port *sport =
555 		container_of(port, struct sa1100_port, port);
556 
557 	if (flags & UART_CONFIG_TYPE &&
558 	    sa1100_request_port(&sport->port) == 0)
559 		sport->port.type = PORT_SA1100;
560 }
561 
562 /*
563  * Verify the new serial_struct (for TIOCSSERIAL).
564  * The only change we allow are to the flags and type, and
565  * even then only between PORT_SA1100 and PORT_UNKNOWN
566  */
567 static int
568 sa1100_verify_port(struct uart_port *port, struct serial_struct *ser)
569 {
570 	struct sa1100_port *sport =
571 		container_of(port, struct sa1100_port, port);
572 	int ret = 0;
573 
574 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_SA1100)
575 		ret = -EINVAL;
576 	if (sport->port.irq != ser->irq)
577 		ret = -EINVAL;
578 	if (ser->io_type != SERIAL_IO_MEM)
579 		ret = -EINVAL;
580 	if (sport->port.uartclk / 16 != ser->baud_base)
581 		ret = -EINVAL;
582 	if ((void *)sport->port.mapbase != ser->iomem_base)
583 		ret = -EINVAL;
584 	if (sport->port.iobase != ser->port)
585 		ret = -EINVAL;
586 	if (ser->hub6 != 0)
587 		ret = -EINVAL;
588 	return ret;
589 }
590 
591 static struct uart_ops sa1100_pops = {
592 	.tx_empty	= sa1100_tx_empty,
593 	.set_mctrl	= sa1100_set_mctrl,
594 	.get_mctrl	= sa1100_get_mctrl,
595 	.stop_tx	= sa1100_stop_tx,
596 	.start_tx	= sa1100_start_tx,
597 	.stop_rx	= sa1100_stop_rx,
598 	.enable_ms	= sa1100_enable_ms,
599 	.break_ctl	= sa1100_break_ctl,
600 	.startup	= sa1100_startup,
601 	.shutdown	= sa1100_shutdown,
602 	.set_termios	= sa1100_set_termios,
603 	.type		= sa1100_type,
604 	.release_port	= sa1100_release_port,
605 	.request_port	= sa1100_request_port,
606 	.config_port	= sa1100_config_port,
607 	.verify_port	= sa1100_verify_port,
608 };
609 
610 static struct sa1100_port sa1100_ports[NR_PORTS];
611 
612 /*
613  * Setup the SA1100 serial ports.  Note that we don't include the IrDA
614  * port here since we have our own SIR/FIR driver (see drivers/net/irda)
615  *
616  * Note also that we support "console=ttySAx" where "x" is either 0 or 1.
617  * Which serial port this ends up being depends on the machine you're
618  * running this kernel on.  I'm not convinced that this is a good idea,
619  * but that's the way it traditionally works.
620  *
621  * Note that NanoEngine UART3 becomes UART2, and UART2 is no longer
622  * used here.
623  */
624 static void __init sa1100_init_ports(void)
625 {
626 	static int first = 1;
627 	int i;
628 
629 	if (!first)
630 		return;
631 	first = 0;
632 
633 	for (i = 0; i < NR_PORTS; i++) {
634 		sa1100_ports[i].port.uartclk   = 3686400;
635 		sa1100_ports[i].port.ops       = &sa1100_pops;
636 		sa1100_ports[i].port.fifosize  = 8;
637 		sa1100_ports[i].port.line      = i;
638 		sa1100_ports[i].port.iotype    = UPIO_MEM;
639 		timer_setup(&sa1100_ports[i].timer, sa1100_timeout, 0);
640 	}
641 
642 	/*
643 	 * make transmit lines outputs, so that when the port
644 	 * is closed, the output is in the MARK state.
645 	 */
646 	PPDR |= PPC_TXD1 | PPC_TXD3;
647 	PPSR |= PPC_TXD1 | PPC_TXD3;
648 }
649 
650 void sa1100_register_uart_fns(struct sa1100_port_fns *fns)
651 {
652 	if (fns->get_mctrl)
653 		sa1100_pops.get_mctrl = fns->get_mctrl;
654 	if (fns->set_mctrl)
655 		sa1100_pops.set_mctrl = fns->set_mctrl;
656 
657 	sa1100_pops.pm       = fns->pm;
658 	/*
659 	 * FIXME: fns->set_wake is unused - this should be called from
660 	 * the suspend() callback if device_may_wakeup(dev)) is set.
661 	 */
662 }
663 
664 void __init sa1100_register_uart(int idx, int port)
665 {
666 	if (idx >= NR_PORTS) {
667 		printk(KERN_ERR "%s: bad index number %d\n", __func__, idx);
668 		return;
669 	}
670 
671 	switch (port) {
672 	case 1:
673 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser1UTCR0;
674 		sa1100_ports[idx].port.mapbase = _Ser1UTCR0;
675 		sa1100_ports[idx].port.irq     = IRQ_Ser1UART;
676 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
677 		break;
678 
679 	case 2:
680 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser2UTCR0;
681 		sa1100_ports[idx].port.mapbase = _Ser2UTCR0;
682 		sa1100_ports[idx].port.irq     = IRQ_Ser2ICP;
683 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
684 		break;
685 
686 	case 3:
687 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser3UTCR0;
688 		sa1100_ports[idx].port.mapbase = _Ser3UTCR0;
689 		sa1100_ports[idx].port.irq     = IRQ_Ser3UART;
690 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
691 		break;
692 
693 	default:
694 		printk(KERN_ERR "%s: bad port number %d\n", __func__, port);
695 	}
696 }
697 
698 
699 #ifdef CONFIG_SERIAL_SA1100_CONSOLE
700 static void sa1100_console_putchar(struct uart_port *port, int ch)
701 {
702 	struct sa1100_port *sport =
703 		container_of(port, struct sa1100_port, port);
704 
705 	while (!(UART_GET_UTSR1(sport) & UTSR1_TNF))
706 		barrier();
707 	UART_PUT_CHAR(sport, ch);
708 }
709 
710 /*
711  * Interrupts are disabled on entering
712  */
713 static void
714 sa1100_console_write(struct console *co, const char *s, unsigned int count)
715 {
716 	struct sa1100_port *sport = &sa1100_ports[co->index];
717 	unsigned int old_utcr3, status;
718 
719 	/*
720 	 *	First, save UTCR3 and then disable interrupts
721 	 */
722 	old_utcr3 = UART_GET_UTCR3(sport);
723 	UART_PUT_UTCR3(sport, (old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE)) |
724 				UTCR3_TXE);
725 
726 	uart_console_write(&sport->port, s, count, sa1100_console_putchar);
727 
728 	/*
729 	 *	Finally, wait for transmitter to become empty
730 	 *	and restore UTCR3
731 	 */
732 	do {
733 		status = UART_GET_UTSR1(sport);
734 	} while (status & UTSR1_TBY);
735 	UART_PUT_UTCR3(sport, old_utcr3);
736 }
737 
738 /*
739  * If the port was already initialised (eg, by a boot loader),
740  * try to determine the current setup.
741  */
742 static void __init
743 sa1100_console_get_options(struct sa1100_port *sport, int *baud,
744 			   int *parity, int *bits)
745 {
746 	unsigned int utcr3;
747 
748 	utcr3 = UART_GET_UTCR3(sport) & (UTCR3_RXE | UTCR3_TXE);
749 	if (utcr3 == (UTCR3_RXE | UTCR3_TXE)) {
750 		/* ok, the port was enabled */
751 		unsigned int utcr0, quot;
752 
753 		utcr0 = UART_GET_UTCR0(sport);
754 
755 		*parity = 'n';
756 		if (utcr0 & UTCR0_PE) {
757 			if (utcr0 & UTCR0_OES)
758 				*parity = 'e';
759 			else
760 				*parity = 'o';
761 		}
762 
763 		if (utcr0 & UTCR0_DSS)
764 			*bits = 8;
765 		else
766 			*bits = 7;
767 
768 		quot = UART_GET_UTCR2(sport) | UART_GET_UTCR1(sport) << 8;
769 		quot &= 0xfff;
770 		*baud = sport->port.uartclk / (16 * (quot + 1));
771 	}
772 }
773 
774 static int __init
775 sa1100_console_setup(struct console *co, char *options)
776 {
777 	struct sa1100_port *sport;
778 	int baud = 9600;
779 	int bits = 8;
780 	int parity = 'n';
781 	int flow = 'n';
782 
783 	/*
784 	 * Check whether an invalid uart number has been specified, and
785 	 * if so, search for the first available port that does have
786 	 * console support.
787 	 */
788 	if (co->index == -1 || co->index >= NR_PORTS)
789 		co->index = 0;
790 	sport = &sa1100_ports[co->index];
791 
792 	if (options)
793 		uart_parse_options(options, &baud, &parity, &bits, &flow);
794 	else
795 		sa1100_console_get_options(sport, &baud, &parity, &bits);
796 
797 	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
798 }
799 
800 static struct uart_driver sa1100_reg;
801 static struct console sa1100_console = {
802 	.name		= "ttySA",
803 	.write		= sa1100_console_write,
804 	.device		= uart_console_device,
805 	.setup		= sa1100_console_setup,
806 	.flags		= CON_PRINTBUFFER,
807 	.index		= -1,
808 	.data		= &sa1100_reg,
809 };
810 
811 static int __init sa1100_rs_console_init(void)
812 {
813 	sa1100_init_ports();
814 	register_console(&sa1100_console);
815 	return 0;
816 }
817 console_initcall(sa1100_rs_console_init);
818 
819 #define SA1100_CONSOLE	&sa1100_console
820 #else
821 #define SA1100_CONSOLE	NULL
822 #endif
823 
824 static struct uart_driver sa1100_reg = {
825 	.owner			= THIS_MODULE,
826 	.driver_name		= "ttySA",
827 	.dev_name		= "ttySA",
828 	.major			= SERIAL_SA1100_MAJOR,
829 	.minor			= MINOR_START,
830 	.nr			= NR_PORTS,
831 	.cons			= SA1100_CONSOLE,
832 };
833 
834 static int sa1100_serial_suspend(struct platform_device *dev, pm_message_t state)
835 {
836 	struct sa1100_port *sport = platform_get_drvdata(dev);
837 
838 	if (sport)
839 		uart_suspend_port(&sa1100_reg, &sport->port);
840 
841 	return 0;
842 }
843 
844 static int sa1100_serial_resume(struct platform_device *dev)
845 {
846 	struct sa1100_port *sport = platform_get_drvdata(dev);
847 
848 	if (sport)
849 		uart_resume_port(&sa1100_reg, &sport->port);
850 
851 	return 0;
852 }
853 
854 static int sa1100_serial_add_one_port(struct sa1100_port *sport, struct platform_device *dev)
855 {
856 	sport->port.dev = &dev->dev;
857 	sport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SA1100_CONSOLE);
858 
859 	// mctrl_gpio_init() requires that the GPIO driver supports interrupts,
860 	// but we need to support GPIO drivers for hardware that has no such
861 	// interrupts.  Use mctrl_gpio_init_noauto() instead.
862 	sport->gpios = mctrl_gpio_init_noauto(sport->port.dev, 0);
863 	if (IS_ERR(sport->gpios)) {
864 		int err = PTR_ERR(sport->gpios);
865 
866 		dev_err(sport->port.dev, "failed to get mctrl gpios: %d\n",
867 			err);
868 
869 		if (err == -EPROBE_DEFER)
870 			return err;
871 
872 		sport->gpios = NULL;
873 	}
874 
875 	platform_set_drvdata(dev, sport);
876 
877 	return uart_add_one_port(&sa1100_reg, &sport->port);
878 }
879 
880 static int sa1100_serial_probe(struct platform_device *dev)
881 {
882 	struct resource *res;
883 	int i;
884 
885 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
886 	if (!res)
887 		return -EINVAL;
888 
889 	for (i = 0; i < NR_PORTS; i++)
890 		if (sa1100_ports[i].port.mapbase == res->start)
891 			break;
892 	if (i == NR_PORTS)
893 		return -ENODEV;
894 
895 	sa1100_serial_add_one_port(&sa1100_ports[i], dev);
896 
897 	return 0;
898 }
899 
900 static int sa1100_serial_remove(struct platform_device *pdev)
901 {
902 	struct sa1100_port *sport = platform_get_drvdata(pdev);
903 
904 	if (sport)
905 		uart_remove_one_port(&sa1100_reg, &sport->port);
906 
907 	return 0;
908 }
909 
910 static struct platform_driver sa11x0_serial_driver = {
911 	.probe		= sa1100_serial_probe,
912 	.remove		= sa1100_serial_remove,
913 	.suspend	= sa1100_serial_suspend,
914 	.resume		= sa1100_serial_resume,
915 	.driver		= {
916 		.name	= "sa11x0-uart",
917 	},
918 };
919 
920 static int __init sa1100_serial_init(void)
921 {
922 	int ret;
923 
924 	printk(KERN_INFO "Serial: SA11x0 driver\n");
925 
926 	sa1100_init_ports();
927 
928 	ret = uart_register_driver(&sa1100_reg);
929 	if (ret == 0) {
930 		ret = platform_driver_register(&sa11x0_serial_driver);
931 		if (ret)
932 			uart_unregister_driver(&sa1100_reg);
933 	}
934 	return ret;
935 }
936 
937 static void __exit sa1100_serial_exit(void)
938 {
939 	platform_driver_unregister(&sa11x0_serial_driver);
940 	uart_unregister_driver(&sa1100_reg);
941 }
942 
943 module_init(sa1100_serial_init);
944 module_exit(sa1100_serial_exit);
945 
946 MODULE_AUTHOR("Deep Blue Solutions Ltd");
947 MODULE_DESCRIPTION("SA1100 generic serial port driver");
948 MODULE_LICENSE("GPL");
949 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_SA1100_MAJOR);
950 MODULE_ALIAS("platform:sa11x0-uart");
951