xref: /openbmc/linux/drivers/tty/serial/sunsu.c (revision 8fc4e4aa)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * su.c: Small serial driver for keyboard/mouse interface on sparc32/PCI
4  *
5  * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
6  * Copyright (C) 1998-1999  Pete Zaitcev   (zaitcev@yahoo.com)
7  *
8  * This is mainly a variation of 8250.c, credits go to authors mentioned
9  * therein.  In fact this driver should be merged into the generic 8250.c
10  * infrastructure perhaps using a 8250_sparc.c module.
11  *
12  * Fixed to use tty_get_baud_rate().
13  *   Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
14  *
15  * Converted to new 2.5.x UART layer.
16  *   David S. Miller (davem@davemloft.net), 2002-Jul-29
17  */
18 
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/spinlock.h>
22 #include <linux/errno.h>
23 #include <linux/tty.h>
24 #include <linux/tty_flip.h>
25 #include <linux/major.h>
26 #include <linux/string.h>
27 #include <linux/ptrace.h>
28 #include <linux/ioport.h>
29 #include <linux/circ_buf.h>
30 #include <linux/serial.h>
31 #include <linux/sysrq.h>
32 #include <linux/console.h>
33 #include <linux/slab.h>
34 #ifdef CONFIG_SERIO
35 #include <linux/serio.h>
36 #endif
37 #include <linux/serial_reg.h>
38 #include <linux/init.h>
39 #include <linux/delay.h>
40 #include <linux/of_device.h>
41 
42 #include <asm/io.h>
43 #include <asm/irq.h>
44 #include <asm/prom.h>
45 #include <asm/setup.h>
46 
47 #include <linux/serial_core.h>
48 #include <linux/sunserialcore.h>
49 
50 /* We are on a NS PC87303 clocked with 24.0 MHz, which results
51  * in a UART clock of 1.8462 MHz.
52  */
53 #define SU_BASE_BAUD	(1846200 / 16)
54 
55 enum su_type { SU_PORT_NONE, SU_PORT_MS, SU_PORT_KBD, SU_PORT_PORT };
56 static char *su_typev[] = { "su(???)", "su(mouse)", "su(kbd)", "su(serial)" };
57 
58 struct serial_uart_config {
59 	char	*name;
60 	int	dfl_xmit_fifo_size;
61 	int	flags;
62 };
63 
64 /*
65  * Here we define the default xmit fifo size used for each type of UART.
66  */
67 static const struct serial_uart_config uart_config[] = {
68 	{ "unknown",	1,	0 },
69 	{ "8250",	1,	0 },
70 	{ "16450",	1,	0 },
71 	{ "16550",	1,	0 },
72 	{ "16550A",	16,	UART_CLEAR_FIFO | UART_USE_FIFO },
73 	{ "Cirrus",	1, 	0 },
74 	{ "ST16650",	1,	UART_CLEAR_FIFO | UART_STARTECH },
75 	{ "ST16650V2",	32,	UART_CLEAR_FIFO | UART_USE_FIFO | UART_STARTECH },
76 	{ "TI16750",	64,	UART_CLEAR_FIFO | UART_USE_FIFO },
77 	{ "Startech",	1,	0 },
78 	{ "16C950/954",	128,	UART_CLEAR_FIFO | UART_USE_FIFO },
79 	{ "ST16654",	64,	UART_CLEAR_FIFO | UART_USE_FIFO | UART_STARTECH },
80 	{ "XR16850",	128,	UART_CLEAR_FIFO | UART_USE_FIFO | UART_STARTECH },
81 	{ "RSA",	2048,	UART_CLEAR_FIFO | UART_USE_FIFO }
82 };
83 
84 struct uart_sunsu_port {
85 	struct uart_port	port;
86 	unsigned char		acr;
87 	unsigned char		ier;
88 	unsigned short		rev;
89 	unsigned char		lcr;
90 	unsigned int		lsr_break_flag;
91 	unsigned int		cflag;
92 
93 	/* Probing information.  */
94 	enum su_type		su_type;
95 	unsigned int		type_probed;	/* XXX Stupid */
96 	unsigned long		reg_size;
97 
98 #ifdef CONFIG_SERIO
99 	struct serio		serio;
100 	int			serio_open;
101 #endif
102 };
103 
104 static unsigned int serial_in(struct uart_sunsu_port *up, int offset)
105 {
106 	offset <<= up->port.regshift;
107 
108 	switch (up->port.iotype) {
109 	case UPIO_HUB6:
110 		outb(up->port.hub6 - 1 + offset, up->port.iobase);
111 		return inb(up->port.iobase + 1);
112 
113 	case UPIO_MEM:
114 		return readb(up->port.membase + offset);
115 
116 	default:
117 		return inb(up->port.iobase + offset);
118 	}
119 }
120 
121 static void serial_out(struct uart_sunsu_port *up, int offset, int value)
122 {
123 #ifndef CONFIG_SPARC64
124 	/*
125 	 * MrCoffee has weird schematics: IRQ4 & P10(?) pins of SuperIO are
126 	 * connected with a gate then go to SlavIO. When IRQ4 goes tristated
127 	 * gate outputs a logical one. Since we use level triggered interrupts
128 	 * we have lockup and watchdog reset. We cannot mask IRQ because
129 	 * keyboard shares IRQ with us (Word has it as Bob Smelik's design).
130 	 * This problem is similar to what Alpha people suffer, see serial.c.
131 	 */
132 	if (offset == UART_MCR)
133 		value |= UART_MCR_OUT2;
134 #endif
135 	offset <<= up->port.regshift;
136 
137 	switch (up->port.iotype) {
138 	case UPIO_HUB6:
139 		outb(up->port.hub6 - 1 + offset, up->port.iobase);
140 		outb(value, up->port.iobase + 1);
141 		break;
142 
143 	case UPIO_MEM:
144 		writeb(value, up->port.membase + offset);
145 		break;
146 
147 	default:
148 		outb(value, up->port.iobase + offset);
149 	}
150 }
151 
152 /*
153  * We used to support using pause I/O for certain machines.  We
154  * haven't supported this for a while, but just in case it's badly
155  * needed for certain old 386 machines, I've left these #define's
156  * in....
157  */
158 #define serial_inp(up, offset)		serial_in(up, offset)
159 #define serial_outp(up, offset, value)	serial_out(up, offset, value)
160 
161 
162 /*
163  * For the 16C950
164  */
165 static void serial_icr_write(struct uart_sunsu_port *up, int offset, int value)
166 {
167 	serial_out(up, UART_SCR, offset);
168 	serial_out(up, UART_ICR, value);
169 }
170 
171 #if 0 /* Unused currently */
172 static unsigned int serial_icr_read(struct uart_sunsu_port *up, int offset)
173 {
174 	unsigned int value;
175 
176 	serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD);
177 	serial_out(up, UART_SCR, offset);
178 	value = serial_in(up, UART_ICR);
179 	serial_icr_write(up, UART_ACR, up->acr);
180 
181 	return value;
182 }
183 #endif
184 
185 #ifdef CONFIG_SERIAL_8250_RSA
186 /*
187  * Attempts to turn on the RSA FIFO.  Returns zero on failure.
188  * We set the port uart clock rate if we succeed.
189  */
190 static int __enable_rsa(struct uart_sunsu_port *up)
191 {
192 	unsigned char mode;
193 	int result;
194 
195 	mode = serial_inp(up, UART_RSA_MSR);
196 	result = mode & UART_RSA_MSR_FIFO;
197 
198 	if (!result) {
199 		serial_outp(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO);
200 		mode = serial_inp(up, UART_RSA_MSR);
201 		result = mode & UART_RSA_MSR_FIFO;
202 	}
203 
204 	if (result)
205 		up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16;
206 
207 	return result;
208 }
209 
210 static void enable_rsa(struct uart_sunsu_port *up)
211 {
212 	if (up->port.type == PORT_RSA) {
213 		if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) {
214 			spin_lock_irq(&up->port.lock);
215 			__enable_rsa(up);
216 			spin_unlock_irq(&up->port.lock);
217 		}
218 		if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
219 			serial_outp(up, UART_RSA_FRR, 0);
220 	}
221 }
222 
223 /*
224  * Attempts to turn off the RSA FIFO.  Returns zero on failure.
225  * It is unknown why interrupts were disabled in here.  However,
226  * the caller is expected to preserve this behaviour by grabbing
227  * the spinlock before calling this function.
228  */
229 static void disable_rsa(struct uart_sunsu_port *up)
230 {
231 	unsigned char mode;
232 	int result;
233 
234 	if (up->port.type == PORT_RSA &&
235 	    up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) {
236 		spin_lock_irq(&up->port.lock);
237 
238 		mode = serial_inp(up, UART_RSA_MSR);
239 		result = !(mode & UART_RSA_MSR_FIFO);
240 
241 		if (!result) {
242 			serial_outp(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO);
243 			mode = serial_inp(up, UART_RSA_MSR);
244 			result = !(mode & UART_RSA_MSR_FIFO);
245 		}
246 
247 		if (result)
248 			up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
249 		spin_unlock_irq(&up->port.lock);
250 	}
251 }
252 #endif /* CONFIG_SERIAL_8250_RSA */
253 
254 static inline void __stop_tx(struct uart_sunsu_port *p)
255 {
256 	if (p->ier & UART_IER_THRI) {
257 		p->ier &= ~UART_IER_THRI;
258 		serial_out(p, UART_IER, p->ier);
259 	}
260 }
261 
262 static void sunsu_stop_tx(struct uart_port *port)
263 {
264 	struct uart_sunsu_port *up =
265 		container_of(port, struct uart_sunsu_port, port);
266 
267 	__stop_tx(up);
268 
269 	/*
270 	 * We really want to stop the transmitter from sending.
271 	 */
272 	if (up->port.type == PORT_16C950) {
273 		up->acr |= UART_ACR_TXDIS;
274 		serial_icr_write(up, UART_ACR, up->acr);
275 	}
276 }
277 
278 static void sunsu_start_tx(struct uart_port *port)
279 {
280 	struct uart_sunsu_port *up =
281 		container_of(port, struct uart_sunsu_port, port);
282 
283 	if (!(up->ier & UART_IER_THRI)) {
284 		up->ier |= UART_IER_THRI;
285 		serial_out(up, UART_IER, up->ier);
286 	}
287 
288 	/*
289 	 * Re-enable the transmitter if we disabled it.
290 	 */
291 	if (up->port.type == PORT_16C950 && up->acr & UART_ACR_TXDIS) {
292 		up->acr &= ~UART_ACR_TXDIS;
293 		serial_icr_write(up, UART_ACR, up->acr);
294 	}
295 }
296 
297 static void sunsu_stop_rx(struct uart_port *port)
298 {
299 	struct uart_sunsu_port *up =
300 		container_of(port, struct uart_sunsu_port, port);
301 
302 	up->ier &= ~UART_IER_RLSI;
303 	up->port.read_status_mask &= ~UART_LSR_DR;
304 	serial_out(up, UART_IER, up->ier);
305 }
306 
307 static void sunsu_enable_ms(struct uart_port *port)
308 {
309 	struct uart_sunsu_port *up =
310 		container_of(port, struct uart_sunsu_port, port);
311 	unsigned long flags;
312 
313 	spin_lock_irqsave(&up->port.lock, flags);
314 	up->ier |= UART_IER_MSI;
315 	serial_out(up, UART_IER, up->ier);
316 	spin_unlock_irqrestore(&up->port.lock, flags);
317 }
318 
319 static void
320 receive_chars(struct uart_sunsu_port *up, unsigned char *status)
321 {
322 	struct tty_port *port = &up->port.state->port;
323 	unsigned char ch, flag;
324 	int max_count = 256;
325 	int saw_console_brk = 0;
326 
327 	do {
328 		ch = serial_inp(up, UART_RX);
329 		flag = TTY_NORMAL;
330 		up->port.icount.rx++;
331 
332 		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
333 				       UART_LSR_FE | UART_LSR_OE))) {
334 			/*
335 			 * For statistics only
336 			 */
337 			if (*status & UART_LSR_BI) {
338 				*status &= ~(UART_LSR_FE | UART_LSR_PE);
339 				up->port.icount.brk++;
340 				if (up->port.cons != NULL &&
341 				    up->port.line == up->port.cons->index)
342 					saw_console_brk = 1;
343 				/*
344 				 * We do the SysRQ and SAK checking
345 				 * here because otherwise the break
346 				 * may get masked by ignore_status_mask
347 				 * or read_status_mask.
348 				 */
349 				if (uart_handle_break(&up->port))
350 					goto ignore_char;
351 			} else if (*status & UART_LSR_PE)
352 				up->port.icount.parity++;
353 			else if (*status & UART_LSR_FE)
354 				up->port.icount.frame++;
355 			if (*status & UART_LSR_OE)
356 				up->port.icount.overrun++;
357 
358 			/*
359 			 * Mask off conditions which should be ingored.
360 			 */
361 			*status &= up->port.read_status_mask;
362 
363 			if (up->port.cons != NULL &&
364 			    up->port.line == up->port.cons->index) {
365 				/* Recover the break flag from console xmit */
366 				*status |= up->lsr_break_flag;
367 				up->lsr_break_flag = 0;
368 			}
369 
370 			if (*status & UART_LSR_BI) {
371 				flag = TTY_BREAK;
372 			} else if (*status & UART_LSR_PE)
373 				flag = TTY_PARITY;
374 			else if (*status & UART_LSR_FE)
375 				flag = TTY_FRAME;
376 		}
377 		if (uart_handle_sysrq_char(&up->port, ch))
378 			goto ignore_char;
379 		if ((*status & up->port.ignore_status_mask) == 0)
380 			tty_insert_flip_char(port, ch, flag);
381 		if (*status & UART_LSR_OE)
382 			/*
383 			 * Overrun is special, since it's reported
384 			 * immediately, and doesn't affect the current
385 			 * character.
386 			 */
387 			 tty_insert_flip_char(port, 0, TTY_OVERRUN);
388 	ignore_char:
389 		*status = serial_inp(up, UART_LSR);
390 	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
391 
392 	if (saw_console_brk)
393 		sun_do_break();
394 }
395 
396 static void transmit_chars(struct uart_sunsu_port *up)
397 {
398 	struct circ_buf *xmit = &up->port.state->xmit;
399 	int count;
400 
401 	if (up->port.x_char) {
402 		serial_outp(up, UART_TX, up->port.x_char);
403 		up->port.icount.tx++;
404 		up->port.x_char = 0;
405 		return;
406 	}
407 	if (uart_tx_stopped(&up->port)) {
408 		sunsu_stop_tx(&up->port);
409 		return;
410 	}
411 	if (uart_circ_empty(xmit)) {
412 		__stop_tx(up);
413 		return;
414 	}
415 
416 	count = up->port.fifosize;
417 	do {
418 		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
419 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
420 		up->port.icount.tx++;
421 		if (uart_circ_empty(xmit))
422 			break;
423 	} while (--count > 0);
424 
425 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
426 		uart_write_wakeup(&up->port);
427 
428 	if (uart_circ_empty(xmit))
429 		__stop_tx(up);
430 }
431 
432 static void check_modem_status(struct uart_sunsu_port *up)
433 {
434 	int status;
435 
436 	status = serial_in(up, UART_MSR);
437 
438 	if ((status & UART_MSR_ANY_DELTA) == 0)
439 		return;
440 
441 	if (status & UART_MSR_TERI)
442 		up->port.icount.rng++;
443 	if (status & UART_MSR_DDSR)
444 		up->port.icount.dsr++;
445 	if (status & UART_MSR_DDCD)
446 		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
447 	if (status & UART_MSR_DCTS)
448 		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
449 
450 	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
451 }
452 
453 static irqreturn_t sunsu_serial_interrupt(int irq, void *dev_id)
454 {
455 	struct uart_sunsu_port *up = dev_id;
456 	unsigned long flags;
457 	unsigned char status;
458 
459 	spin_lock_irqsave(&up->port.lock, flags);
460 
461 	do {
462 		status = serial_inp(up, UART_LSR);
463 		if (status & UART_LSR_DR)
464 			receive_chars(up, &status);
465 		check_modem_status(up);
466 		if (status & UART_LSR_THRE)
467 			transmit_chars(up);
468 
469 		tty_flip_buffer_push(&up->port.state->port);
470 
471 	} while (!(serial_in(up, UART_IIR) & UART_IIR_NO_INT));
472 
473 	spin_unlock_irqrestore(&up->port.lock, flags);
474 
475 	return IRQ_HANDLED;
476 }
477 
478 /* Separate interrupt handling path for keyboard/mouse ports.  */
479 
480 static void
481 sunsu_change_speed(struct uart_port *port, unsigned int cflag,
482 		   unsigned int iflag, unsigned int quot);
483 
484 static void sunsu_change_mouse_baud(struct uart_sunsu_port *up)
485 {
486 	unsigned int cur_cflag = up->cflag;
487 	int quot, new_baud;
488 
489 	up->cflag &= ~CBAUD;
490 	up->cflag |= suncore_mouse_baud_cflag_next(cur_cflag, &new_baud);
491 
492 	quot = up->port.uartclk / (16 * new_baud);
493 
494 	sunsu_change_speed(&up->port, up->cflag, 0, quot);
495 }
496 
497 static void receive_kbd_ms_chars(struct uart_sunsu_port *up, int is_break)
498 {
499 	do {
500 		unsigned char ch = serial_inp(up, UART_RX);
501 
502 		/* Stop-A is handled by drivers/char/keyboard.c now. */
503 		if (up->su_type == SU_PORT_KBD) {
504 #ifdef CONFIG_SERIO
505 			serio_interrupt(&up->serio, ch, 0);
506 #endif
507 		} else if (up->su_type == SU_PORT_MS) {
508 			int ret = suncore_mouse_baud_detection(ch, is_break);
509 
510 			switch (ret) {
511 			case 2:
512 				sunsu_change_mouse_baud(up);
513 				fallthrough;
514 			case 1:
515 				break;
516 
517 			case 0:
518 #ifdef CONFIG_SERIO
519 				serio_interrupt(&up->serio, ch, 0);
520 #endif
521 				break;
522 			}
523 		}
524 	} while (serial_in(up, UART_LSR) & UART_LSR_DR);
525 }
526 
527 static irqreturn_t sunsu_kbd_ms_interrupt(int irq, void *dev_id)
528 {
529 	struct uart_sunsu_port *up = dev_id;
530 
531 	if (!(serial_in(up, UART_IIR) & UART_IIR_NO_INT)) {
532 		unsigned char status = serial_inp(up, UART_LSR);
533 
534 		if ((status & UART_LSR_DR) || (status & UART_LSR_BI))
535 			receive_kbd_ms_chars(up, (status & UART_LSR_BI) != 0);
536 	}
537 
538 	return IRQ_HANDLED;
539 }
540 
541 static unsigned int sunsu_tx_empty(struct uart_port *port)
542 {
543 	struct uart_sunsu_port *up =
544 		container_of(port, struct uart_sunsu_port, port);
545 	unsigned long flags;
546 	unsigned int ret;
547 
548 	spin_lock_irqsave(&up->port.lock, flags);
549 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
550 	spin_unlock_irqrestore(&up->port.lock, flags);
551 
552 	return ret;
553 }
554 
555 static unsigned int sunsu_get_mctrl(struct uart_port *port)
556 {
557 	struct uart_sunsu_port *up =
558 		container_of(port, struct uart_sunsu_port, port);
559 	unsigned char status;
560 	unsigned int ret;
561 
562 	status = serial_in(up, UART_MSR);
563 
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 
576 static void sunsu_set_mctrl(struct uart_port *port, unsigned int mctrl)
577 {
578 	struct uart_sunsu_port *up =
579 		container_of(port, struct uart_sunsu_port, port);
580 	unsigned char mcr = 0;
581 
582 	if (mctrl & TIOCM_RTS)
583 		mcr |= UART_MCR_RTS;
584 	if (mctrl & TIOCM_DTR)
585 		mcr |= UART_MCR_DTR;
586 	if (mctrl & TIOCM_OUT1)
587 		mcr |= UART_MCR_OUT1;
588 	if (mctrl & TIOCM_OUT2)
589 		mcr |= UART_MCR_OUT2;
590 	if (mctrl & TIOCM_LOOP)
591 		mcr |= UART_MCR_LOOP;
592 
593 	serial_out(up, UART_MCR, mcr);
594 }
595 
596 static void sunsu_break_ctl(struct uart_port *port, int break_state)
597 {
598 	struct uart_sunsu_port *up =
599 		container_of(port, struct uart_sunsu_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 
611 static int sunsu_startup(struct uart_port *port)
612 {
613 	struct uart_sunsu_port *up =
614 		container_of(port, struct uart_sunsu_port, port);
615 	unsigned long flags;
616 	int retval;
617 
618 	if (up->port.type == PORT_16C950) {
619 		/* Wake up and initialize UART */
620 		up->acr = 0;
621 		serial_outp(up, UART_LCR, 0xBF);
622 		serial_outp(up, UART_EFR, UART_EFR_ECB);
623 		serial_outp(up, UART_IER, 0);
624 		serial_outp(up, UART_LCR, 0);
625 		serial_icr_write(up, UART_CSR, 0); /* Reset the UART */
626 		serial_outp(up, UART_LCR, 0xBF);
627 		serial_outp(up, UART_EFR, UART_EFR_ECB);
628 		serial_outp(up, UART_LCR, 0);
629 	}
630 
631 #ifdef CONFIG_SERIAL_8250_RSA
632 	/*
633 	 * If this is an RSA port, see if we can kick it up to the
634 	 * higher speed clock.
635 	 */
636 	enable_rsa(up);
637 #endif
638 
639 	/*
640 	 * Clear the FIFO buffers and disable them.
641 	 * (they will be reenabled in set_termios())
642 	 */
643 	if (uart_config[up->port.type].flags & UART_CLEAR_FIFO) {
644 		serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
645 		serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
646 				UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
647 		serial_outp(up, UART_FCR, 0);
648 	}
649 
650 	/*
651 	 * Clear the interrupt registers.
652 	 */
653 	(void) serial_inp(up, UART_LSR);
654 	(void) serial_inp(up, UART_RX);
655 	(void) serial_inp(up, UART_IIR);
656 	(void) serial_inp(up, UART_MSR);
657 
658 	/*
659 	 * At this point, there's no way the LSR could still be 0xff;
660 	 * if it is, then bail out, because there's likely no UART
661 	 * here.
662 	 */
663 	if (!(up->port.flags & UPF_BUGGY_UART) &&
664 	    (serial_inp(up, UART_LSR) == 0xff)) {
665 		printk("ttyS%d: LSR safety check engaged!\n", up->port.line);
666 		return -ENODEV;
667 	}
668 
669 	if (up->su_type != SU_PORT_PORT) {
670 		retval = request_irq(up->port.irq, sunsu_kbd_ms_interrupt,
671 				     IRQF_SHARED, su_typev[up->su_type], up);
672 	} else {
673 		retval = request_irq(up->port.irq, sunsu_serial_interrupt,
674 				     IRQF_SHARED, su_typev[up->su_type], up);
675 	}
676 	if (retval) {
677 		printk("su: Cannot register IRQ %d\n", up->port.irq);
678 		return retval;
679 	}
680 
681 	/*
682 	 * Now, initialize the UART
683 	 */
684 	serial_outp(up, UART_LCR, UART_LCR_WLEN8);
685 
686 	spin_lock_irqsave(&up->port.lock, flags);
687 
688 	up->port.mctrl |= TIOCM_OUT2;
689 
690 	sunsu_set_mctrl(&up->port, up->port.mctrl);
691 	spin_unlock_irqrestore(&up->port.lock, flags);
692 
693 	/*
694 	 * Finally, enable interrupts.  Note: Modem status interrupts
695 	 * are set via set_termios(), which will be occurring imminently
696 	 * anyway, so we don't enable them here.
697 	 */
698 	up->ier = UART_IER_RLSI | UART_IER_RDI;
699 	serial_outp(up, UART_IER, up->ier);
700 
701 	if (up->port.flags & UPF_FOURPORT) {
702 		unsigned int icp;
703 		/*
704 		 * Enable interrupts on the AST Fourport board
705 		 */
706 		icp = (up->port.iobase & 0xfe0) | 0x01f;
707 		outb_p(0x80, icp);
708 		(void) inb_p(icp);
709 	}
710 
711 	/*
712 	 * And clear the interrupt registers again for luck.
713 	 */
714 	(void) serial_inp(up, UART_LSR);
715 	(void) serial_inp(up, UART_RX);
716 	(void) serial_inp(up, UART_IIR);
717 	(void) serial_inp(up, UART_MSR);
718 
719 	return 0;
720 }
721 
722 static void sunsu_shutdown(struct uart_port *port)
723 {
724 	struct uart_sunsu_port *up =
725 		container_of(port, struct uart_sunsu_port, port);
726 	unsigned long flags;
727 
728 	/*
729 	 * Disable interrupts from this port
730 	 */
731 	up->ier = 0;
732 	serial_outp(up, UART_IER, 0);
733 
734 	spin_lock_irqsave(&up->port.lock, flags);
735 	if (up->port.flags & UPF_FOURPORT) {
736 		/* reset interrupts on the AST Fourport board */
737 		inb((up->port.iobase & 0xfe0) | 0x1f);
738 		up->port.mctrl |= TIOCM_OUT1;
739 	} else
740 		up->port.mctrl &= ~TIOCM_OUT2;
741 
742 	sunsu_set_mctrl(&up->port, up->port.mctrl);
743 	spin_unlock_irqrestore(&up->port.lock, flags);
744 
745 	/*
746 	 * Disable break condition and FIFOs
747 	 */
748 	serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC);
749 	serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
750 				  UART_FCR_CLEAR_RCVR |
751 				  UART_FCR_CLEAR_XMIT);
752 	serial_outp(up, UART_FCR, 0);
753 
754 #ifdef CONFIG_SERIAL_8250_RSA
755 	/*
756 	 * Reset the RSA board back to 115kbps compat mode.
757 	 */
758 	disable_rsa(up);
759 #endif
760 
761 	/*
762 	 * Read data port to reset things.
763 	 */
764 	(void) serial_in(up, UART_RX);
765 
766 	free_irq(up->port.irq, up);
767 }
768 
769 static void
770 sunsu_change_speed(struct uart_port *port, unsigned int cflag,
771 		   unsigned int iflag, unsigned int quot)
772 {
773 	struct uart_sunsu_port *up =
774 		container_of(port, struct uart_sunsu_port, port);
775 	unsigned char cval, fcr = 0;
776 	unsigned long flags;
777 
778 	switch (cflag & CSIZE) {
779 	case CS5:
780 		cval = 0x00;
781 		break;
782 	case CS6:
783 		cval = 0x01;
784 		break;
785 	case CS7:
786 		cval = 0x02;
787 		break;
788 	default:
789 	case CS8:
790 		cval = 0x03;
791 		break;
792 	}
793 
794 	if (cflag & CSTOPB)
795 		cval |= 0x04;
796 	if (cflag & PARENB)
797 		cval |= UART_LCR_PARITY;
798 	if (!(cflag & PARODD))
799 		cval |= UART_LCR_EPAR;
800 #ifdef CMSPAR
801 	if (cflag & CMSPAR)
802 		cval |= UART_LCR_SPAR;
803 #endif
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 ((up->port.uartclk / quot) < (2400 * 16))
816 			fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
817 #ifdef CONFIG_SERIAL_8250_RSA
818 		else if (up->port.type == PORT_RSA)
819 			fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_14;
820 #endif
821 		else
822 			fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_8;
823 	}
824 	if (up->port.type == PORT_16750)
825 		fcr |= UART_FCR7_64BYTE;
826 
827 	/*
828 	 * Ok, we're now changing the port state.  Do it with
829 	 * interrupts disabled.
830 	 */
831 	spin_lock_irqsave(&up->port.lock, flags);
832 
833 	/*
834 	 * Update the per-port timeout.
835 	 */
836 	uart_update_timeout(port, cflag, (port->uartclk / (16 * quot)));
837 
838 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
839 	if (iflag & INPCK)
840 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
841 	if (iflag & (IGNBRK | BRKINT | PARMRK))
842 		up->port.read_status_mask |= UART_LSR_BI;
843 
844 	/*
845 	 * Characteres to ignore
846 	 */
847 	up->port.ignore_status_mask = 0;
848 	if (iflag & IGNPAR)
849 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
850 	if (iflag & IGNBRK) {
851 		up->port.ignore_status_mask |= UART_LSR_BI;
852 		/*
853 		 * If we're ignoring parity and break indicators,
854 		 * ignore overruns too (for real raw support).
855 		 */
856 		if (iflag & IGNPAR)
857 			up->port.ignore_status_mask |= UART_LSR_OE;
858 	}
859 
860 	/*
861 	 * ignore all characters if CREAD is not set
862 	 */
863 	if ((cflag & CREAD) == 0)
864 		up->port.ignore_status_mask |= UART_LSR_DR;
865 
866 	/*
867 	 * CTS flow control flag and modem status interrupts
868 	 */
869 	up->ier &= ~UART_IER_MSI;
870 	if (UART_ENABLE_MS(&up->port, cflag))
871 		up->ier |= UART_IER_MSI;
872 
873 	serial_out(up, UART_IER, up->ier);
874 
875 	if (uart_config[up->port.type].flags & UART_STARTECH) {
876 		serial_outp(up, UART_LCR, 0xBF);
877 		serial_outp(up, UART_EFR, cflag & CRTSCTS ? UART_EFR_CTS :0);
878 	}
879 	serial_outp(up, UART_LCR, cval | UART_LCR_DLAB);/* set DLAB */
880 	serial_outp(up, UART_DLL, quot & 0xff);		/* LS of divisor */
881 	serial_outp(up, UART_DLM, quot >> 8);		/* MS of divisor */
882 	if (up->port.type == PORT_16750)
883 		serial_outp(up, UART_FCR, fcr);		/* set fcr */
884 	serial_outp(up, UART_LCR, cval);		/* reset DLAB */
885 	up->lcr = cval;					/* Save LCR */
886 	if (up->port.type != PORT_16750) {
887 		if (fcr & UART_FCR_ENABLE_FIFO) {
888 			/* emulated UARTs (Lucent Venus 167x) need two steps */
889 			serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
890 		}
891 		serial_outp(up, UART_FCR, fcr);		/* set fcr */
892 	}
893 
894 	up->cflag = cflag;
895 
896 	spin_unlock_irqrestore(&up->port.lock, flags);
897 }
898 
899 static void
900 sunsu_set_termios(struct uart_port *port, struct ktermios *termios,
901 		  struct ktermios *old)
902 {
903 	unsigned int baud, quot;
904 
905 	/*
906 	 * Ask the core to calculate the divisor for us.
907 	 */
908 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
909 	quot = uart_get_divisor(port, baud);
910 
911 	sunsu_change_speed(port, termios->c_cflag, termios->c_iflag, quot);
912 }
913 
914 static void sunsu_release_port(struct uart_port *port)
915 {
916 }
917 
918 static int sunsu_request_port(struct uart_port *port)
919 {
920 	return 0;
921 }
922 
923 static void sunsu_config_port(struct uart_port *port, int flags)
924 {
925 	struct uart_sunsu_port *up =
926 		container_of(port, struct uart_sunsu_port, port);
927 
928 	if (flags & UART_CONFIG_TYPE) {
929 		/*
930 		 * We are supposed to call autoconfig here, but this requires
931 		 * splitting all the OBP probing crap from the UART probing.
932 		 * We'll do it when we kill sunsu.c altogether.
933 		 */
934 		port->type = up->type_probed;	/* XXX */
935 	}
936 }
937 
938 static int
939 sunsu_verify_port(struct uart_port *port, struct serial_struct *ser)
940 {
941 	return -EINVAL;
942 }
943 
944 static const char *
945 sunsu_type(struct uart_port *port)
946 {
947 	int type = port->type;
948 
949 	if (type >= ARRAY_SIZE(uart_config))
950 		type = 0;
951 	return uart_config[type].name;
952 }
953 
954 static const struct uart_ops sunsu_pops = {
955 	.tx_empty	= sunsu_tx_empty,
956 	.set_mctrl	= sunsu_set_mctrl,
957 	.get_mctrl	= sunsu_get_mctrl,
958 	.stop_tx	= sunsu_stop_tx,
959 	.start_tx	= sunsu_start_tx,
960 	.stop_rx	= sunsu_stop_rx,
961 	.enable_ms	= sunsu_enable_ms,
962 	.break_ctl	= sunsu_break_ctl,
963 	.startup	= sunsu_startup,
964 	.shutdown	= sunsu_shutdown,
965 	.set_termios	= sunsu_set_termios,
966 	.type		= sunsu_type,
967 	.release_port	= sunsu_release_port,
968 	.request_port	= sunsu_request_port,
969 	.config_port	= sunsu_config_port,
970 	.verify_port	= sunsu_verify_port,
971 };
972 
973 #define UART_NR	4
974 
975 static struct uart_sunsu_port sunsu_ports[UART_NR];
976 static int nr_inst; /* Number of already registered ports */
977 
978 #ifdef CONFIG_SERIO
979 
980 static DEFINE_SPINLOCK(sunsu_serio_lock);
981 
982 static int sunsu_serio_write(struct serio *serio, unsigned char ch)
983 {
984 	struct uart_sunsu_port *up = serio->port_data;
985 	unsigned long flags;
986 	int lsr;
987 
988 	spin_lock_irqsave(&sunsu_serio_lock, flags);
989 
990 	do {
991 		lsr = serial_in(up, UART_LSR);
992 	} while (!(lsr & UART_LSR_THRE));
993 
994 	/* Send the character out. */
995 	serial_out(up, UART_TX, ch);
996 
997 	spin_unlock_irqrestore(&sunsu_serio_lock, flags);
998 
999 	return 0;
1000 }
1001 
1002 static int sunsu_serio_open(struct serio *serio)
1003 {
1004 	struct uart_sunsu_port *up = serio->port_data;
1005 	unsigned long flags;
1006 	int ret;
1007 
1008 	spin_lock_irqsave(&sunsu_serio_lock, flags);
1009 	if (!up->serio_open) {
1010 		up->serio_open = 1;
1011 		ret = 0;
1012 	} else
1013 		ret = -EBUSY;
1014 	spin_unlock_irqrestore(&sunsu_serio_lock, flags);
1015 
1016 	return ret;
1017 }
1018 
1019 static void sunsu_serio_close(struct serio *serio)
1020 {
1021 	struct uart_sunsu_port *up = serio->port_data;
1022 	unsigned long flags;
1023 
1024 	spin_lock_irqsave(&sunsu_serio_lock, flags);
1025 	up->serio_open = 0;
1026 	spin_unlock_irqrestore(&sunsu_serio_lock, flags);
1027 }
1028 
1029 #endif /* CONFIG_SERIO */
1030 
1031 static void sunsu_autoconfig(struct uart_sunsu_port *up)
1032 {
1033 	unsigned char status1, status2, scratch, scratch2, scratch3;
1034 	unsigned char save_lcr, save_mcr;
1035 	unsigned long flags;
1036 
1037 	if (up->su_type == SU_PORT_NONE)
1038 		return;
1039 
1040 	up->type_probed = PORT_UNKNOWN;
1041 	up->port.iotype = UPIO_MEM;
1042 
1043 	spin_lock_irqsave(&up->port.lock, flags);
1044 
1045 	if (!(up->port.flags & UPF_BUGGY_UART)) {
1046 		/*
1047 		 * Do a simple existence test first; if we fail this, there's
1048 		 * no point trying anything else.
1049 		 *
1050 		 * 0x80 is used as a nonsense port to prevent against false
1051 		 * positives due to ISA bus float.  The assumption is that
1052 		 * 0x80 is a non-existent port; which should be safe since
1053 		 * include/asm/io.h also makes this assumption.
1054 		 */
1055 		scratch = serial_inp(up, UART_IER);
1056 		serial_outp(up, UART_IER, 0);
1057 #ifdef __i386__
1058 		outb(0xff, 0x080);
1059 #endif
1060 		scratch2 = serial_inp(up, UART_IER);
1061 		serial_outp(up, UART_IER, 0x0f);
1062 #ifdef __i386__
1063 		outb(0, 0x080);
1064 #endif
1065 		scratch3 = serial_inp(up, UART_IER);
1066 		serial_outp(up, UART_IER, scratch);
1067 		if (scratch2 != 0 || scratch3 != 0x0F)
1068 			goto out;	/* We failed; there's nothing here */
1069 	}
1070 
1071 	save_mcr = serial_in(up, UART_MCR);
1072 	save_lcr = serial_in(up, UART_LCR);
1073 
1074 	/*
1075 	 * Check to see if a UART is really there.  Certain broken
1076 	 * internal modems based on the Rockwell chipset fail this
1077 	 * test, because they apparently don't implement the loopback
1078 	 * test mode.  So this test is skipped on the COM 1 through
1079 	 * COM 4 ports.  This *should* be safe, since no board
1080 	 * manufacturer would be stupid enough to design a board
1081 	 * that conflicts with COM 1-4 --- we hope!
1082 	 */
1083 	if (!(up->port.flags & UPF_SKIP_TEST)) {
1084 		serial_outp(up, UART_MCR, UART_MCR_LOOP | 0x0A);
1085 		status1 = serial_inp(up, UART_MSR) & 0xF0;
1086 		serial_outp(up, UART_MCR, save_mcr);
1087 		if (status1 != 0x90)
1088 			goto out;	/* We failed loopback test */
1089 	}
1090 	serial_outp(up, UART_LCR, 0xBF);	/* set up for StarTech test */
1091 	serial_outp(up, UART_EFR, 0);		/* EFR is the same as FCR */
1092 	serial_outp(up, UART_LCR, 0);
1093 	serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
1094 	scratch = serial_in(up, UART_IIR) >> 6;
1095 	switch (scratch) {
1096 		case 0:
1097 			up->port.type = PORT_16450;
1098 			break;
1099 		case 1:
1100 			up->port.type = PORT_UNKNOWN;
1101 			break;
1102 		case 2:
1103 			up->port.type = PORT_16550;
1104 			break;
1105 		case 3:
1106 			up->port.type = PORT_16550A;
1107 			break;
1108 	}
1109 	if (up->port.type == PORT_16550A) {
1110 		/* Check for Startech UART's */
1111 		serial_outp(up, UART_LCR, UART_LCR_DLAB);
1112 		if (serial_in(up, UART_EFR) == 0) {
1113 			up->port.type = PORT_16650;
1114 		} else {
1115 			serial_outp(up, UART_LCR, 0xBF);
1116 			if (serial_in(up, UART_EFR) == 0)
1117 				up->port.type = PORT_16650V2;
1118 		}
1119 	}
1120 	if (up->port.type == PORT_16550A) {
1121 		/* Check for TI 16750 */
1122 		serial_outp(up, UART_LCR, save_lcr | UART_LCR_DLAB);
1123 		serial_outp(up, UART_FCR,
1124 			    UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
1125 		scratch = serial_in(up, UART_IIR) >> 5;
1126 		if (scratch == 7) {
1127 			/*
1128 			 * If this is a 16750, and not a cheap UART
1129 			 * clone, then it should only go into 64 byte
1130 			 * mode if the UART_FCR7_64BYTE bit was set
1131 			 * while UART_LCR_DLAB was latched.
1132 			 */
1133  			serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
1134 			serial_outp(up, UART_LCR, 0);
1135 			serial_outp(up, UART_FCR,
1136 				    UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE);
1137 			scratch = serial_in(up, UART_IIR) >> 5;
1138 			if (scratch == 6)
1139 				up->port.type = PORT_16750;
1140 		}
1141 		serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
1142 	}
1143 	serial_outp(up, UART_LCR, save_lcr);
1144 	if (up->port.type == PORT_16450) {
1145 		scratch = serial_in(up, UART_SCR);
1146 		serial_outp(up, UART_SCR, 0xa5);
1147 		status1 = serial_in(up, UART_SCR);
1148 		serial_outp(up, UART_SCR, 0x5a);
1149 		status2 = serial_in(up, UART_SCR);
1150 		serial_outp(up, UART_SCR, scratch);
1151 
1152 		if ((status1 != 0xa5) || (status2 != 0x5a))
1153 			up->port.type = PORT_8250;
1154 	}
1155 
1156 	up->port.fifosize = uart_config[up->port.type].dfl_xmit_fifo_size;
1157 
1158 	if (up->port.type == PORT_UNKNOWN)
1159 		goto out;
1160 	up->type_probed = up->port.type;	/* XXX */
1161 
1162 	/*
1163 	 * Reset the UART.
1164 	 */
1165 #ifdef CONFIG_SERIAL_8250_RSA
1166 	if (up->port.type == PORT_RSA)
1167 		serial_outp(up, UART_RSA_FRR, 0);
1168 #endif
1169 	serial_outp(up, UART_MCR, save_mcr);
1170 	serial_outp(up, UART_FCR, (UART_FCR_ENABLE_FIFO |
1171 				     UART_FCR_CLEAR_RCVR |
1172 				     UART_FCR_CLEAR_XMIT));
1173 	serial_outp(up, UART_FCR, 0);
1174 	(void)serial_in(up, UART_RX);
1175 	serial_outp(up, UART_IER, 0);
1176 
1177 out:
1178 	spin_unlock_irqrestore(&up->port.lock, flags);
1179 }
1180 
1181 static struct uart_driver sunsu_reg = {
1182 	.owner			= THIS_MODULE,
1183 	.driver_name		= "sunsu",
1184 	.dev_name		= "ttyS",
1185 	.major			= TTY_MAJOR,
1186 };
1187 
1188 static int sunsu_kbd_ms_init(struct uart_sunsu_port *up)
1189 {
1190 	int quot, baud;
1191 #ifdef CONFIG_SERIO
1192 	struct serio *serio;
1193 #endif
1194 
1195 	if (up->su_type == SU_PORT_KBD) {
1196 		up->cflag = B1200 | CS8 | CLOCAL | CREAD;
1197 		baud = 1200;
1198 	} else {
1199 		up->cflag = B4800 | CS8 | CLOCAL | CREAD;
1200 		baud = 4800;
1201 	}
1202 	quot = up->port.uartclk / (16 * baud);
1203 
1204 	sunsu_autoconfig(up);
1205 	if (up->port.type == PORT_UNKNOWN)
1206 		return -ENODEV;
1207 
1208 	printk("%pOF: %s port at %llx, irq %u\n",
1209 	       up->port.dev->of_node,
1210 	       (up->su_type == SU_PORT_KBD) ? "Keyboard" : "Mouse",
1211 	       (unsigned long long) up->port.mapbase,
1212 	       up->port.irq);
1213 
1214 #ifdef CONFIG_SERIO
1215 	serio = &up->serio;
1216 	serio->port_data = up;
1217 
1218 	serio->id.type = SERIO_RS232;
1219 	if (up->su_type == SU_PORT_KBD) {
1220 		serio->id.proto = SERIO_SUNKBD;
1221 		strlcpy(serio->name, "sukbd", sizeof(serio->name));
1222 	} else {
1223 		serio->id.proto = SERIO_SUN;
1224 		serio->id.extra = 1;
1225 		strlcpy(serio->name, "sums", sizeof(serio->name));
1226 	}
1227 	strlcpy(serio->phys,
1228 		(!(up->port.line & 1) ? "su/serio0" : "su/serio1"),
1229 		sizeof(serio->phys));
1230 
1231 	serio->write = sunsu_serio_write;
1232 	serio->open = sunsu_serio_open;
1233 	serio->close = sunsu_serio_close;
1234 	serio->dev.parent = up->port.dev;
1235 
1236 	serio_register_port(serio);
1237 #endif
1238 
1239 	sunsu_change_speed(&up->port, up->cflag, 0, quot);
1240 
1241 	sunsu_startup(&up->port);
1242 	return 0;
1243 }
1244 
1245 /*
1246  * ------------------------------------------------------------
1247  * Serial console driver
1248  * ------------------------------------------------------------
1249  */
1250 
1251 #ifdef CONFIG_SERIAL_SUNSU_CONSOLE
1252 
1253 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1254 
1255 /*
1256  *	Wait for transmitter & holding register to empty
1257  */
1258 static void wait_for_xmitr(struct uart_sunsu_port *up)
1259 {
1260 	unsigned int status, tmout = 10000;
1261 
1262 	/* Wait up to 10ms for the character(s) to be sent. */
1263 	do {
1264 		status = serial_in(up, UART_LSR);
1265 
1266 		if (status & UART_LSR_BI)
1267 			up->lsr_break_flag = UART_LSR_BI;
1268 
1269 		if (--tmout == 0)
1270 			break;
1271 		udelay(1);
1272 	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1273 
1274 	/* Wait up to 1s for flow control if necessary */
1275 	if (up->port.flags & UPF_CONS_FLOW) {
1276 		tmout = 1000000;
1277 		while (--tmout &&
1278 		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
1279 			udelay(1);
1280 	}
1281 }
1282 
1283 static void sunsu_console_putchar(struct uart_port *port, int ch)
1284 {
1285 	struct uart_sunsu_port *up =
1286 		container_of(port, struct uart_sunsu_port, port);
1287 
1288 	wait_for_xmitr(up);
1289 	serial_out(up, UART_TX, ch);
1290 }
1291 
1292 /*
1293  *	Print a string to the serial port trying not to disturb
1294  *	any possible real use of the port...
1295  */
1296 static void sunsu_console_write(struct console *co, const char *s,
1297 				unsigned int count)
1298 {
1299 	struct uart_sunsu_port *up = &sunsu_ports[co->index];
1300 	unsigned long flags;
1301 	unsigned int ier;
1302 	int locked = 1;
1303 
1304 	if (up->port.sysrq || oops_in_progress)
1305 		locked = spin_trylock_irqsave(&up->port.lock, flags);
1306 	else
1307 		spin_lock_irqsave(&up->port.lock, flags);
1308 
1309 	/*
1310 	 *	First save the UER then disable the interrupts
1311 	 */
1312 	ier = serial_in(up, UART_IER);
1313 	serial_out(up, UART_IER, 0);
1314 
1315 	uart_console_write(&up->port, s, count, sunsu_console_putchar);
1316 
1317 	/*
1318 	 *	Finally, wait for transmitter to become empty
1319 	 *	and restore the IER
1320 	 */
1321 	wait_for_xmitr(up);
1322 	serial_out(up, UART_IER, ier);
1323 
1324 	if (locked)
1325 		spin_unlock_irqrestore(&up->port.lock, flags);
1326 }
1327 
1328 /*
1329  *	Setup initial baud/bits/parity. We do two things here:
1330  *	- construct a cflag setting for the first su_open()
1331  *	- initialize the serial port
1332  *	Return non-zero if we didn't find a serial port.
1333  */
1334 static int __init sunsu_console_setup(struct console *co, char *options)
1335 {
1336 	static struct ktermios dummy;
1337 	struct ktermios termios;
1338 	struct uart_port *port;
1339 
1340 	printk("Console: ttyS%d (SU)\n",
1341 	       (sunsu_reg.minor - 64) + co->index);
1342 
1343 	if (co->index > nr_inst)
1344 		return -ENODEV;
1345 	port = &sunsu_ports[co->index].port;
1346 
1347 	/*
1348 	 * Temporary fix.
1349 	 */
1350 	spin_lock_init(&port->lock);
1351 
1352 	/* Get firmware console settings.  */
1353 	sunserial_console_termios(co, port->dev->of_node);
1354 
1355 	memset(&termios, 0, sizeof(struct ktermios));
1356 	termios.c_cflag = co->cflag;
1357 	port->mctrl |= TIOCM_DTR;
1358 	port->ops->set_termios(port, &termios, &dummy);
1359 
1360 	return 0;
1361 }
1362 
1363 static struct console sunsu_console = {
1364 	.name	=	"ttyS",
1365 	.write	=	sunsu_console_write,
1366 	.device	=	uart_console_device,
1367 	.setup	=	sunsu_console_setup,
1368 	.flags	=	CON_PRINTBUFFER,
1369 	.index	=	-1,
1370 	.data	=	&sunsu_reg,
1371 };
1372 
1373 /*
1374  *	Register console.
1375  */
1376 
1377 static inline struct console *SUNSU_CONSOLE(void)
1378 {
1379 	return &sunsu_console;
1380 }
1381 #else
1382 #define SUNSU_CONSOLE()			(NULL)
1383 #define sunsu_serial_console_init()	do { } while (0)
1384 #endif
1385 
1386 static enum su_type su_get_type(struct device_node *dp)
1387 {
1388 	struct device_node *ap = of_find_node_by_path("/aliases");
1389 	enum su_type rc = SU_PORT_PORT;
1390 
1391 	if (ap) {
1392 		const char *keyb = of_get_property(ap, "keyboard", NULL);
1393 		const char *ms = of_get_property(ap, "mouse", NULL);
1394 		struct device_node *match;
1395 
1396 		if (keyb) {
1397 			match = of_find_node_by_path(keyb);
1398 
1399 			/*
1400 			 * The pointer is used as an identifier not
1401 			 * as a pointer, we can drop the refcount on
1402 			 * the of__node immediately after getting it.
1403 			 */
1404 			of_node_put(match);
1405 
1406 			if (dp == match) {
1407 				rc = SU_PORT_KBD;
1408 				goto out;
1409 			}
1410 		}
1411 		if (ms) {
1412 			match = of_find_node_by_path(ms);
1413 
1414 			of_node_put(match);
1415 
1416 			if (dp == match) {
1417 				rc = SU_PORT_MS;
1418 				goto out;
1419 			}
1420 		}
1421 	}
1422 
1423 out:
1424 	of_node_put(ap);
1425 	return rc;
1426 }
1427 
1428 static int su_probe(struct platform_device *op)
1429 {
1430 	struct device_node *dp = op->dev.of_node;
1431 	struct uart_sunsu_port *up;
1432 	struct resource *rp;
1433 	enum su_type type;
1434 	bool ignore_line;
1435 	int err;
1436 
1437 	type = su_get_type(dp);
1438 	if (type == SU_PORT_PORT) {
1439 		if (nr_inst >= UART_NR)
1440 			return -EINVAL;
1441 		up = &sunsu_ports[nr_inst];
1442 	} else {
1443 		up = kzalloc(sizeof(*up), GFP_KERNEL);
1444 		if (!up)
1445 			return -ENOMEM;
1446 	}
1447 
1448 	up->port.line = nr_inst;
1449 
1450 	spin_lock_init(&up->port.lock);
1451 
1452 	up->su_type = type;
1453 
1454 	rp = &op->resource[0];
1455 	up->port.mapbase = rp->start;
1456 	up->reg_size = resource_size(rp);
1457 	up->port.membase = of_ioremap(rp, 0, up->reg_size, "su");
1458 	if (!up->port.membase) {
1459 		if (type != SU_PORT_PORT)
1460 			kfree(up);
1461 		return -ENOMEM;
1462 	}
1463 
1464 	up->port.irq = op->archdata.irqs[0];
1465 
1466 	up->port.dev = &op->dev;
1467 
1468 	up->port.type = PORT_UNKNOWN;
1469 	up->port.uartclk = (SU_BASE_BAUD * 16);
1470 	up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SUNSU_CONSOLE);
1471 
1472 	err = 0;
1473 	if (up->su_type == SU_PORT_KBD || up->su_type == SU_PORT_MS) {
1474 		err = sunsu_kbd_ms_init(up);
1475 		if (err) {
1476 			of_iounmap(&op->resource[0],
1477 				   up->port.membase, up->reg_size);
1478 			kfree(up);
1479 			return err;
1480 		}
1481 		platform_set_drvdata(op, up);
1482 
1483 		nr_inst++;
1484 
1485 		return 0;
1486 	}
1487 
1488 	up->port.flags |= UPF_BOOT_AUTOCONF;
1489 
1490 	sunsu_autoconfig(up);
1491 
1492 	err = -ENODEV;
1493 	if (up->port.type == PORT_UNKNOWN)
1494 		goto out_unmap;
1495 
1496 	up->port.ops = &sunsu_pops;
1497 
1498 	ignore_line = false;
1499 	if (of_node_name_eq(dp, "rsc-console") ||
1500 	    of_node_name_eq(dp, "lom-console"))
1501 		ignore_line = true;
1502 
1503 	sunserial_console_match(SUNSU_CONSOLE(), dp,
1504 				&sunsu_reg, up->port.line,
1505 				ignore_line);
1506 	err = uart_add_one_port(&sunsu_reg, &up->port);
1507 	if (err)
1508 		goto out_unmap;
1509 
1510 	platform_set_drvdata(op, up);
1511 
1512 	nr_inst++;
1513 
1514 	return 0;
1515 
1516 out_unmap:
1517 	of_iounmap(&op->resource[0], up->port.membase, up->reg_size);
1518 	kfree(up);
1519 	return err;
1520 }
1521 
1522 static int su_remove(struct platform_device *op)
1523 {
1524 	struct uart_sunsu_port *up = platform_get_drvdata(op);
1525 	bool kbdms = false;
1526 
1527 	if (up->su_type == SU_PORT_MS ||
1528 	    up->su_type == SU_PORT_KBD)
1529 		kbdms = true;
1530 
1531 	if (kbdms) {
1532 #ifdef CONFIG_SERIO
1533 		serio_unregister_port(&up->serio);
1534 #endif
1535 	} else if (up->port.type != PORT_UNKNOWN)
1536 		uart_remove_one_port(&sunsu_reg, &up->port);
1537 
1538 	if (up->port.membase)
1539 		of_iounmap(&op->resource[0], up->port.membase, up->reg_size);
1540 
1541 	if (kbdms)
1542 		kfree(up);
1543 
1544 	return 0;
1545 }
1546 
1547 static const struct of_device_id su_match[] = {
1548 	{
1549 		.name = "su",
1550 	},
1551 	{
1552 		.name = "su_pnp",
1553 	},
1554 	{
1555 		.name = "serial",
1556 		.compatible = "su",
1557 	},
1558 	{
1559 		.type = "serial",
1560 		.compatible = "su",
1561 	},
1562 	{},
1563 };
1564 MODULE_DEVICE_TABLE(of, su_match);
1565 
1566 static struct platform_driver su_driver = {
1567 	.driver = {
1568 		.name = "su",
1569 		.of_match_table = su_match,
1570 	},
1571 	.probe		= su_probe,
1572 	.remove		= su_remove,
1573 };
1574 
1575 static int __init sunsu_init(void)
1576 {
1577 	struct device_node *dp;
1578 	int err;
1579 	int num_uart = 0;
1580 
1581 	for_each_node_by_name(dp, "su") {
1582 		if (su_get_type(dp) == SU_PORT_PORT)
1583 			num_uart++;
1584 	}
1585 	for_each_node_by_name(dp, "su_pnp") {
1586 		if (su_get_type(dp) == SU_PORT_PORT)
1587 			num_uart++;
1588 	}
1589 	for_each_node_by_name(dp, "serial") {
1590 		if (of_device_is_compatible(dp, "su")) {
1591 			if (su_get_type(dp) == SU_PORT_PORT)
1592 				num_uart++;
1593 		}
1594 	}
1595 	for_each_node_by_type(dp, "serial") {
1596 		if (of_device_is_compatible(dp, "su")) {
1597 			if (su_get_type(dp) == SU_PORT_PORT)
1598 				num_uart++;
1599 		}
1600 	}
1601 
1602 	if (num_uart) {
1603 		err = sunserial_register_minors(&sunsu_reg, num_uart);
1604 		if (err)
1605 			return err;
1606 	}
1607 
1608 	err = platform_driver_register(&su_driver);
1609 	if (err && num_uart)
1610 		sunserial_unregister_minors(&sunsu_reg, num_uart);
1611 
1612 	return err;
1613 }
1614 
1615 static void __exit sunsu_exit(void)
1616 {
1617 	platform_driver_unregister(&su_driver);
1618 	if (sunsu_reg.nr)
1619 		sunserial_unregister_minors(&sunsu_reg, sunsu_reg.nr);
1620 }
1621 
1622 module_init(sunsu_init);
1623 module_exit(sunsu_exit);
1624 
1625 MODULE_AUTHOR("Eddie C. Dost, Peter Zaitcev, and David S. Miller");
1626 MODULE_DESCRIPTION("Sun SU serial port driver");
1627 MODULE_VERSION("2.0");
1628 MODULE_LICENSE("GPL");
1629