xref: /openbmc/linux/drivers/tty/serial/sa1100.c (revision 1504b6f9)
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 	tty_flip_buffer_push(&sport->port.state->port);
227 }
228 
229 static void sa1100_tx_chars(struct sa1100_port *sport)
230 {
231 	struct circ_buf *xmit = &sport->port.state->xmit;
232 
233 	if (sport->port.x_char) {
234 		UART_PUT_CHAR(sport, sport->port.x_char);
235 		sport->port.icount.tx++;
236 		sport->port.x_char = 0;
237 		return;
238 	}
239 
240 	/*
241 	 * Check the modem control lines before
242 	 * transmitting anything.
243 	 */
244 	sa1100_mctrl_check(sport);
245 
246 	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
247 		sa1100_stop_tx(&sport->port);
248 		return;
249 	}
250 
251 	/*
252 	 * Tried using FIFO (not checking TNF) for fifo fill:
253 	 * still had the '4 bytes repeated' problem.
254 	 */
255 	while (UART_GET_UTSR1(sport) & UTSR1_TNF) {
256 		UART_PUT_CHAR(sport, xmit->buf[xmit->tail]);
257 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
258 		sport->port.icount.tx++;
259 		if (uart_circ_empty(xmit))
260 			break;
261 	}
262 
263 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
264 		uart_write_wakeup(&sport->port);
265 
266 	if (uart_circ_empty(xmit))
267 		sa1100_stop_tx(&sport->port);
268 }
269 
270 static irqreturn_t sa1100_int(int irq, void *dev_id)
271 {
272 	struct sa1100_port *sport = dev_id;
273 	unsigned int status, pass_counter = 0;
274 
275 	spin_lock(&sport->port.lock);
276 	status = UART_GET_UTSR0(sport);
277 	status &= SM_TO_UTSR0(sport->port.read_status_mask) | ~UTSR0_TFS;
278 	do {
279 		if (status & (UTSR0_RFS | UTSR0_RID)) {
280 			/* Clear the receiver idle bit, if set */
281 			if (status & UTSR0_RID)
282 				UART_PUT_UTSR0(sport, UTSR0_RID);
283 			sa1100_rx_chars(sport);
284 		}
285 
286 		/* Clear the relevant break bits */
287 		if (status & (UTSR0_RBB | UTSR0_REB))
288 			UART_PUT_UTSR0(sport, status & (UTSR0_RBB | UTSR0_REB));
289 
290 		if (status & UTSR0_RBB)
291 			sport->port.icount.brk++;
292 
293 		if (status & UTSR0_REB)
294 			uart_handle_break(&sport->port);
295 
296 		if (status & UTSR0_TFS)
297 			sa1100_tx_chars(sport);
298 		if (pass_counter++ > SA1100_ISR_PASS_LIMIT)
299 			break;
300 		status = UART_GET_UTSR0(sport);
301 		status &= SM_TO_UTSR0(sport->port.read_status_mask) |
302 			  ~UTSR0_TFS;
303 	} while (status & (UTSR0_TFS | UTSR0_RFS | UTSR0_RID));
304 	spin_unlock(&sport->port.lock);
305 
306 	return IRQ_HANDLED;
307 }
308 
309 /*
310  * Return TIOCSER_TEMT when transmitter is not busy.
311  */
312 static unsigned int sa1100_tx_empty(struct uart_port *port)
313 {
314 	struct sa1100_port *sport =
315 		container_of(port, struct sa1100_port, port);
316 
317 	return UART_GET_UTSR1(sport) & UTSR1_TBY ? 0 : TIOCSER_TEMT;
318 }
319 
320 static unsigned int sa1100_get_mctrl(struct uart_port *port)
321 {
322 	struct sa1100_port *sport =
323 		container_of(port, struct sa1100_port, port);
324 	int ret = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
325 
326 	mctrl_gpio_get(sport->gpios, &ret);
327 
328 	return ret;
329 }
330 
331 static void sa1100_set_mctrl(struct uart_port *port, unsigned int mctrl)
332 {
333 	struct sa1100_port *sport =
334 		container_of(port, struct sa1100_port, port);
335 
336 	mctrl_gpio_set(sport->gpios, mctrl);
337 }
338 
339 /*
340  * Interrupts always disabled.
341  */
342 static void sa1100_break_ctl(struct uart_port *port, int break_state)
343 {
344 	struct sa1100_port *sport =
345 		container_of(port, struct sa1100_port, port);
346 	unsigned long flags;
347 	unsigned int utcr3;
348 
349 	spin_lock_irqsave(&sport->port.lock, flags);
350 	utcr3 = UART_GET_UTCR3(sport);
351 	if (break_state == -1)
352 		utcr3 |= UTCR3_BRK;
353 	else
354 		utcr3 &= ~UTCR3_BRK;
355 	UART_PUT_UTCR3(sport, utcr3);
356 	spin_unlock_irqrestore(&sport->port.lock, flags);
357 }
358 
359 static int sa1100_startup(struct uart_port *port)
360 {
361 	struct sa1100_port *sport =
362 		container_of(port, struct sa1100_port, port);
363 	int retval;
364 
365 	/*
366 	 * Allocate the IRQ
367 	 */
368 	retval = request_irq(sport->port.irq, sa1100_int, 0,
369 			     "sa11x0-uart", sport);
370 	if (retval)
371 		return retval;
372 
373 	/*
374 	 * Finally, clear and enable interrupts
375 	 */
376 	UART_PUT_UTSR0(sport, -1);
377 	UART_PUT_UTCR3(sport, UTCR3_RXE | UTCR3_TXE | UTCR3_RIE);
378 
379 	/*
380 	 * Enable modem status interrupts
381 	 */
382 	spin_lock_irq(&sport->port.lock);
383 	sa1100_enable_ms(&sport->port);
384 	spin_unlock_irq(&sport->port.lock);
385 
386 	return 0;
387 }
388 
389 static void sa1100_shutdown(struct uart_port *port)
390 {
391 	struct sa1100_port *sport =
392 		container_of(port, struct sa1100_port, port);
393 
394 	/*
395 	 * Stop our timer.
396 	 */
397 	del_timer_sync(&sport->timer);
398 
399 	/*
400 	 * Free the interrupt
401 	 */
402 	free_irq(sport->port.irq, sport);
403 
404 	/*
405 	 * Disable all interrupts, port and break condition.
406 	 */
407 	UART_PUT_UTCR3(sport, 0);
408 }
409 
410 static void
411 sa1100_set_termios(struct uart_port *port, struct ktermios *termios,
412 		   const struct ktermios *old)
413 {
414 	struct sa1100_port *sport =
415 		container_of(port, struct sa1100_port, port);
416 	unsigned long flags;
417 	unsigned int utcr0, old_utcr3, baud, quot;
418 	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
419 
420 	/*
421 	 * We only support CS7 and CS8.
422 	 */
423 	while ((termios->c_cflag & CSIZE) != CS7 &&
424 	       (termios->c_cflag & CSIZE) != CS8) {
425 		termios->c_cflag &= ~CSIZE;
426 		termios->c_cflag |= old_csize;
427 		old_csize = CS8;
428 	}
429 
430 	if ((termios->c_cflag & CSIZE) == CS8)
431 		utcr0 = UTCR0_DSS;
432 	else
433 		utcr0 = 0;
434 
435 	if (termios->c_cflag & CSTOPB)
436 		utcr0 |= UTCR0_SBS;
437 	if (termios->c_cflag & PARENB) {
438 		utcr0 |= UTCR0_PE;
439 		if (!(termios->c_cflag & PARODD))
440 			utcr0 |= UTCR0_OES;
441 	}
442 
443 	/*
444 	 * Ask the core to calculate the divisor for us.
445 	 */
446 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
447 	quot = uart_get_divisor(port, baud);
448 
449 	del_timer_sync(&sport->timer);
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 	/*
482 	 * Update the per-port timeout.
483 	 */
484 	uart_update_timeout(port, termios->c_cflag, baud);
485 
486 	/*
487 	 * disable interrupts and drain transmitter
488 	 */
489 	old_utcr3 = UART_GET_UTCR3(sport);
490 	UART_PUT_UTCR3(sport, old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE));
491 
492 	while (UART_GET_UTSR1(sport) & UTSR1_TBY)
493 		barrier();
494 
495 	/* then, disable everything */
496 	UART_PUT_UTCR3(sport, 0);
497 
498 	/* set the parity, stop bits and data size */
499 	UART_PUT_UTCR0(sport, utcr0);
500 
501 	/* set the baud rate */
502 	quot -= 1;
503 	UART_PUT_UTCR1(sport, ((quot & 0xf00) >> 8));
504 	UART_PUT_UTCR2(sport, (quot & 0xff));
505 
506 	UART_PUT_UTSR0(sport, -1);
507 
508 	UART_PUT_UTCR3(sport, old_utcr3);
509 
510 	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
511 		sa1100_enable_ms(&sport->port);
512 
513 	spin_unlock_irqrestore(&sport->port.lock, flags);
514 }
515 
516 static const char *sa1100_type(struct uart_port *port)
517 {
518 	struct sa1100_port *sport =
519 		container_of(port, struct sa1100_port, port);
520 
521 	return sport->port.type == PORT_SA1100 ? "SA1100" : NULL;
522 }
523 
524 /*
525  * Release the memory region(s) being used by 'port'.
526  */
527 static void sa1100_release_port(struct uart_port *port)
528 {
529 	struct sa1100_port *sport =
530 		container_of(port, struct sa1100_port, port);
531 
532 	release_mem_region(sport->port.mapbase, UART_PORT_SIZE);
533 }
534 
535 /*
536  * Request the memory region(s) being used by 'port'.
537  */
538 static int sa1100_request_port(struct uart_port *port)
539 {
540 	struct sa1100_port *sport =
541 		container_of(port, struct sa1100_port, port);
542 
543 	return request_mem_region(sport->port.mapbase, UART_PORT_SIZE,
544 			"sa11x0-uart") != NULL ? 0 : -EBUSY;
545 }
546 
547 /*
548  * Configure/autoconfigure the port.
549  */
550 static void sa1100_config_port(struct uart_port *port, int flags)
551 {
552 	struct sa1100_port *sport =
553 		container_of(port, struct sa1100_port, port);
554 
555 	if (flags & UART_CONFIG_TYPE &&
556 	    sa1100_request_port(&sport->port) == 0)
557 		sport->port.type = PORT_SA1100;
558 }
559 
560 /*
561  * Verify the new serial_struct (for TIOCSSERIAL).
562  * The only change we allow are to the flags and type, and
563  * even then only between PORT_SA1100 and PORT_UNKNOWN
564  */
565 static int
566 sa1100_verify_port(struct uart_port *port, struct serial_struct *ser)
567 {
568 	struct sa1100_port *sport =
569 		container_of(port, struct sa1100_port, port);
570 	int ret = 0;
571 
572 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_SA1100)
573 		ret = -EINVAL;
574 	if (sport->port.irq != ser->irq)
575 		ret = -EINVAL;
576 	if (ser->io_type != SERIAL_IO_MEM)
577 		ret = -EINVAL;
578 	if (sport->port.uartclk / 16 != ser->baud_base)
579 		ret = -EINVAL;
580 	if ((void *)sport->port.mapbase != ser->iomem_base)
581 		ret = -EINVAL;
582 	if (sport->port.iobase != ser->port)
583 		ret = -EINVAL;
584 	if (ser->hub6 != 0)
585 		ret = -EINVAL;
586 	return ret;
587 }
588 
589 static struct uart_ops sa1100_pops = {
590 	.tx_empty	= sa1100_tx_empty,
591 	.set_mctrl	= sa1100_set_mctrl,
592 	.get_mctrl	= sa1100_get_mctrl,
593 	.stop_tx	= sa1100_stop_tx,
594 	.start_tx	= sa1100_start_tx,
595 	.stop_rx	= sa1100_stop_rx,
596 	.enable_ms	= sa1100_enable_ms,
597 	.break_ctl	= sa1100_break_ctl,
598 	.startup	= sa1100_startup,
599 	.shutdown	= sa1100_shutdown,
600 	.set_termios	= sa1100_set_termios,
601 	.type		= sa1100_type,
602 	.release_port	= sa1100_release_port,
603 	.request_port	= sa1100_request_port,
604 	.config_port	= sa1100_config_port,
605 	.verify_port	= sa1100_verify_port,
606 };
607 
608 static struct sa1100_port sa1100_ports[NR_PORTS];
609 
610 /*
611  * Setup the SA1100 serial ports.  Note that we don't include the IrDA
612  * port here since we have our own SIR/FIR driver (see drivers/net/irda)
613  *
614  * Note also that we support "console=ttySAx" where "x" is either 0 or 1.
615  * Which serial port this ends up being depends on the machine you're
616  * running this kernel on.  I'm not convinced that this is a good idea,
617  * but that's the way it traditionally works.
618  *
619  * Note that NanoEngine UART3 becomes UART2, and UART2 is no longer
620  * used here.
621  */
622 static void __init sa1100_init_ports(void)
623 {
624 	static int first = 1;
625 	int i;
626 
627 	if (!first)
628 		return;
629 	first = 0;
630 
631 	for (i = 0; i < NR_PORTS; i++) {
632 		sa1100_ports[i].port.uartclk   = 3686400;
633 		sa1100_ports[i].port.ops       = &sa1100_pops;
634 		sa1100_ports[i].port.fifosize  = 8;
635 		sa1100_ports[i].port.line      = i;
636 		sa1100_ports[i].port.iotype    = UPIO_MEM;
637 		timer_setup(&sa1100_ports[i].timer, sa1100_timeout, 0);
638 	}
639 
640 	/*
641 	 * make transmit lines outputs, so that when the port
642 	 * is closed, the output is in the MARK state.
643 	 */
644 	PPDR |= PPC_TXD1 | PPC_TXD3;
645 	PPSR |= PPC_TXD1 | PPC_TXD3;
646 }
647 
648 void sa1100_register_uart_fns(struct sa1100_port_fns *fns)
649 {
650 	if (fns->get_mctrl)
651 		sa1100_pops.get_mctrl = fns->get_mctrl;
652 	if (fns->set_mctrl)
653 		sa1100_pops.set_mctrl = fns->set_mctrl;
654 
655 	sa1100_pops.pm       = fns->pm;
656 	/*
657 	 * FIXME: fns->set_wake is unused - this should be called from
658 	 * the suspend() callback if device_may_wakeup(dev)) is set.
659 	 */
660 }
661 
662 void __init sa1100_register_uart(int idx, int port)
663 {
664 	if (idx >= NR_PORTS) {
665 		printk(KERN_ERR "%s: bad index number %d\n", __func__, idx);
666 		return;
667 	}
668 
669 	switch (port) {
670 	case 1:
671 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser1UTCR0;
672 		sa1100_ports[idx].port.mapbase = _Ser1UTCR0;
673 		sa1100_ports[idx].port.irq     = IRQ_Ser1UART;
674 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
675 		break;
676 
677 	case 2:
678 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser2UTCR0;
679 		sa1100_ports[idx].port.mapbase = _Ser2UTCR0;
680 		sa1100_ports[idx].port.irq     = IRQ_Ser2ICP;
681 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
682 		break;
683 
684 	case 3:
685 		sa1100_ports[idx].port.membase = (void __iomem *)&Ser3UTCR0;
686 		sa1100_ports[idx].port.mapbase = _Ser3UTCR0;
687 		sa1100_ports[idx].port.irq     = IRQ_Ser3UART;
688 		sa1100_ports[idx].port.flags   = UPF_BOOT_AUTOCONF;
689 		break;
690 
691 	default:
692 		printk(KERN_ERR "%s: bad port number %d\n", __func__, port);
693 	}
694 }
695 
696 
697 #ifdef CONFIG_SERIAL_SA1100_CONSOLE
698 static void sa1100_console_putchar(struct uart_port *port, unsigned char ch)
699 {
700 	struct sa1100_port *sport =
701 		container_of(port, struct sa1100_port, port);
702 
703 	while (!(UART_GET_UTSR1(sport) & UTSR1_TNF))
704 		barrier();
705 	UART_PUT_CHAR(sport, ch);
706 }
707 
708 /*
709  * Interrupts are disabled on entering
710  */
711 static void
712 sa1100_console_write(struct console *co, const char *s, unsigned int count)
713 {
714 	struct sa1100_port *sport = &sa1100_ports[co->index];
715 	unsigned int old_utcr3, status;
716 
717 	/*
718 	 *	First, save UTCR3 and then disable interrupts
719 	 */
720 	old_utcr3 = UART_GET_UTCR3(sport);
721 	UART_PUT_UTCR3(sport, (old_utcr3 & ~(UTCR3_RIE | UTCR3_TIE)) |
722 				UTCR3_TXE);
723 
724 	uart_console_write(&sport->port, s, count, sa1100_console_putchar);
725 
726 	/*
727 	 *	Finally, wait for transmitter to become empty
728 	 *	and restore UTCR3
729 	 */
730 	do {
731 		status = UART_GET_UTSR1(sport);
732 	} while (status & UTSR1_TBY);
733 	UART_PUT_UTCR3(sport, old_utcr3);
734 }
735 
736 /*
737  * If the port was already initialised (eg, by a boot loader),
738  * try to determine the current setup.
739  */
740 static void __init
741 sa1100_console_get_options(struct sa1100_port *sport, int *baud,
742 			   int *parity, int *bits)
743 {
744 	unsigned int utcr3;
745 
746 	utcr3 = UART_GET_UTCR3(sport) & (UTCR3_RXE | UTCR3_TXE);
747 	if (utcr3 == (UTCR3_RXE | UTCR3_TXE)) {
748 		/* ok, the port was enabled */
749 		unsigned int utcr0, quot;
750 
751 		utcr0 = UART_GET_UTCR0(sport);
752 
753 		*parity = 'n';
754 		if (utcr0 & UTCR0_PE) {
755 			if (utcr0 & UTCR0_OES)
756 				*parity = 'e';
757 			else
758 				*parity = 'o';
759 		}
760 
761 		if (utcr0 & UTCR0_DSS)
762 			*bits = 8;
763 		else
764 			*bits = 7;
765 
766 		quot = UART_GET_UTCR2(sport) | UART_GET_UTCR1(sport) << 8;
767 		quot &= 0xfff;
768 		*baud = sport->port.uartclk / (16 * (quot + 1));
769 	}
770 }
771 
772 static int __init
773 sa1100_console_setup(struct console *co, char *options)
774 {
775 	struct sa1100_port *sport;
776 	int baud = 9600;
777 	int bits = 8;
778 	int parity = 'n';
779 	int flow = 'n';
780 
781 	/*
782 	 * Check whether an invalid uart number has been specified, and
783 	 * if so, search for the first available port that does have
784 	 * console support.
785 	 */
786 	if (co->index == -1 || co->index >= NR_PORTS)
787 		co->index = 0;
788 	sport = &sa1100_ports[co->index];
789 
790 	if (options)
791 		uart_parse_options(options, &baud, &parity, &bits, &flow);
792 	else
793 		sa1100_console_get_options(sport, &baud, &parity, &bits);
794 
795 	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
796 }
797 
798 static struct uart_driver sa1100_reg;
799 static struct console sa1100_console = {
800 	.name		= "ttySA",
801 	.write		= sa1100_console_write,
802 	.device		= uart_console_device,
803 	.setup		= sa1100_console_setup,
804 	.flags		= CON_PRINTBUFFER,
805 	.index		= -1,
806 	.data		= &sa1100_reg,
807 };
808 
809 static int __init sa1100_rs_console_init(void)
810 {
811 	sa1100_init_ports();
812 	register_console(&sa1100_console);
813 	return 0;
814 }
815 console_initcall(sa1100_rs_console_init);
816 
817 #define SA1100_CONSOLE	&sa1100_console
818 #else
819 #define SA1100_CONSOLE	NULL
820 #endif
821 
822 static struct uart_driver sa1100_reg = {
823 	.owner			= THIS_MODULE,
824 	.driver_name		= "ttySA",
825 	.dev_name		= "ttySA",
826 	.major			= SERIAL_SA1100_MAJOR,
827 	.minor			= MINOR_START,
828 	.nr			= NR_PORTS,
829 	.cons			= SA1100_CONSOLE,
830 };
831 
832 static int sa1100_serial_suspend(struct platform_device *dev, pm_message_t state)
833 {
834 	struct sa1100_port *sport = platform_get_drvdata(dev);
835 
836 	if (sport)
837 		uart_suspend_port(&sa1100_reg, &sport->port);
838 
839 	return 0;
840 }
841 
842 static int sa1100_serial_resume(struct platform_device *dev)
843 {
844 	struct sa1100_port *sport = platform_get_drvdata(dev);
845 
846 	if (sport)
847 		uart_resume_port(&sa1100_reg, &sport->port);
848 
849 	return 0;
850 }
851 
852 static int sa1100_serial_add_one_port(struct sa1100_port *sport, struct platform_device *dev)
853 {
854 	sport->port.dev = &dev->dev;
855 	sport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SA1100_CONSOLE);
856 
857 	// mctrl_gpio_init() requires that the GPIO driver supports interrupts,
858 	// but we need to support GPIO drivers for hardware that has no such
859 	// interrupts.  Use mctrl_gpio_init_noauto() instead.
860 	sport->gpios = mctrl_gpio_init_noauto(sport->port.dev, 0);
861 	if (IS_ERR(sport->gpios)) {
862 		int err = PTR_ERR(sport->gpios);
863 
864 		dev_err(sport->port.dev, "failed to get mctrl gpios: %d\n",
865 			err);
866 
867 		if (err == -EPROBE_DEFER)
868 			return err;
869 
870 		sport->gpios = NULL;
871 	}
872 
873 	platform_set_drvdata(dev, sport);
874 
875 	return uart_add_one_port(&sa1100_reg, &sport->port);
876 }
877 
878 static int sa1100_serial_probe(struct platform_device *dev)
879 {
880 	struct resource *res;
881 	int i;
882 
883 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
884 	if (!res)
885 		return -EINVAL;
886 
887 	for (i = 0; i < NR_PORTS; i++)
888 		if (sa1100_ports[i].port.mapbase == res->start)
889 			break;
890 	if (i == NR_PORTS)
891 		return -ENODEV;
892 
893 	sa1100_serial_add_one_port(&sa1100_ports[i], dev);
894 
895 	return 0;
896 }
897 
898 static int sa1100_serial_remove(struct platform_device *pdev)
899 {
900 	struct sa1100_port *sport = platform_get_drvdata(pdev);
901 
902 	if (sport)
903 		uart_remove_one_port(&sa1100_reg, &sport->port);
904 
905 	return 0;
906 }
907 
908 static struct platform_driver sa11x0_serial_driver = {
909 	.probe		= sa1100_serial_probe,
910 	.remove		= sa1100_serial_remove,
911 	.suspend	= sa1100_serial_suspend,
912 	.resume		= sa1100_serial_resume,
913 	.driver		= {
914 		.name	= "sa11x0-uart",
915 	},
916 };
917 
918 static int __init sa1100_serial_init(void)
919 {
920 	int ret;
921 
922 	printk(KERN_INFO "Serial: SA11x0 driver\n");
923 
924 	sa1100_init_ports();
925 
926 	ret = uart_register_driver(&sa1100_reg);
927 	if (ret == 0) {
928 		ret = platform_driver_register(&sa11x0_serial_driver);
929 		if (ret)
930 			uart_unregister_driver(&sa1100_reg);
931 	}
932 	return ret;
933 }
934 
935 static void __exit sa1100_serial_exit(void)
936 {
937 	platform_driver_unregister(&sa11x0_serial_driver);
938 	uart_unregister_driver(&sa1100_reg);
939 }
940 
941 module_init(sa1100_serial_init);
942 module_exit(sa1100_serial_exit);
943 
944 MODULE_AUTHOR("Deep Blue Solutions Ltd");
945 MODULE_DESCRIPTION("SA1100 generic serial port driver");
946 MODULE_LICENSE("GPL");
947 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_SA1100_MAJOR);
948 MODULE_ALIAS("platform:sa11x0-uart");
949