xref: /openbmc/linux/drivers/tty/serial/pmac_zilog.c (revision 1504b6f9)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Driver for PowerMac Z85c30 based ESCC cell found in the
4  * "macio" ASICs of various PowerMac models
5  *
6  * Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
7  *
8  * Derived from drivers/macintosh/macserial.c by Paul Mackerras
9  * and drivers/serial/sunzilog.c by David S. Miller
10  *
11  * Hrm... actually, I ripped most of sunzilog (Thanks David !) and
12  * adapted special tweaks needed for us. I don't think it's worth
13  * merging back those though. The DMA code still has to get in
14  * and once done, I expect that driver to remain fairly stable in
15  * the long term, unless we change the driver model again...
16  *
17  * 2004-08-06 Harald Welte <laforge@gnumonks.org>
18  *	- Enable BREAK interrupt
19  *	- Add support for sysreq
20  *
21  * TODO:   - Add DMA support
22  *         - Defer port shutdown to a few seconds after close
23  *         - maybe put something right into uap->clk_divisor
24  */
25 
26 #undef DEBUG
27 #undef USE_CTRL_O_SYSRQ
28 
29 #include <linux/module.h>
30 #include <linux/tty.h>
31 
32 #include <linux/tty_flip.h>
33 #include <linux/major.h>
34 #include <linux/string.h>
35 #include <linux/fcntl.h>
36 #include <linux/mm.h>
37 #include <linux/kernel.h>
38 #include <linux/delay.h>
39 #include <linux/init.h>
40 #include <linux/console.h>
41 #include <linux/adb.h>
42 #include <linux/pmu.h>
43 #include <linux/bitops.h>
44 #include <linux/sysrq.h>
45 #include <linux/mutex.h>
46 #include <linux/of_address.h>
47 #include <linux/of_irq.h>
48 #include <asm/sections.h>
49 #include <linux/io.h>
50 #include <asm/irq.h>
51 
52 #ifdef CONFIG_PPC_PMAC
53 #include <asm/machdep.h>
54 #include <asm/pmac_feature.h>
55 #include <asm/macio.h>
56 #else
57 #include <linux/platform_device.h>
58 #define of_machine_is_compatible(x) (0)
59 #endif
60 
61 #include <linux/serial.h>
62 #include <linux/serial_core.h>
63 
64 #include "pmac_zilog.h"
65 
66 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
67 MODULE_DESCRIPTION("Driver for the Mac and PowerMac serial ports.");
68 MODULE_LICENSE("GPL");
69 
70 #ifdef CONFIG_SERIAL_PMACZILOG_TTYS
71 #define PMACZILOG_MAJOR		TTY_MAJOR
72 #define PMACZILOG_MINOR		64
73 #define PMACZILOG_NAME		"ttyS"
74 #else
75 #define PMACZILOG_MAJOR		204
76 #define PMACZILOG_MINOR		192
77 #define PMACZILOG_NAME		"ttyPZ"
78 #endif
79 
80 #define pmz_debug(fmt, arg...)	pr_debug("ttyPZ%d: " fmt, uap->port.line, ## arg)
81 #define pmz_error(fmt, arg...)	pr_err("ttyPZ%d: " fmt, uap->port.line, ## arg)
82 #define pmz_info(fmt, arg...)	pr_info("ttyPZ%d: " fmt, uap->port.line, ## arg)
83 
84 /*
85  * For the sake of early serial console, we can do a pre-probe
86  * (optional) of the ports at rather early boot time.
87  */
88 static struct uart_pmac_port	pmz_ports[MAX_ZS_PORTS];
89 static int			pmz_ports_count;
90 
91 static struct uart_driver pmz_uart_reg = {
92 	.owner		=	THIS_MODULE,
93 	.driver_name	=	PMACZILOG_NAME,
94 	.dev_name	=	PMACZILOG_NAME,
95 	.major		=	PMACZILOG_MAJOR,
96 	.minor		=	PMACZILOG_MINOR,
97 };
98 
99 
100 /*
101  * Load all registers to reprogram the port
102  * This function must only be called when the TX is not busy.  The UART
103  * port lock must be held and local interrupts disabled.
104  */
105 static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
106 {
107 	int i;
108 
109 	/* Let pending transmits finish.  */
110 	for (i = 0; i < 1000; i++) {
111 		unsigned char stat = read_zsreg(uap, R1);
112 		if (stat & ALL_SNT)
113 			break;
114 		udelay(100);
115 	}
116 
117 	ZS_CLEARERR(uap);
118 	zssync(uap);
119 	ZS_CLEARFIFO(uap);
120 	zssync(uap);
121 	ZS_CLEARERR(uap);
122 
123 	/* Disable all interrupts.  */
124 	write_zsreg(uap, R1,
125 		    regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
126 
127 	/* Set parity, sync config, stop bits, and clock divisor.  */
128 	write_zsreg(uap, R4, regs[R4]);
129 
130 	/* Set misc. TX/RX control bits.  */
131 	write_zsreg(uap, R10, regs[R10]);
132 
133 	/* Set TX/RX controls sans the enable bits.  */
134 	write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
135 	write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
136 
137 	/* now set R7 "prime" on ESCC */
138 	write_zsreg(uap, R15, regs[R15] | EN85C30);
139 	write_zsreg(uap, R7, regs[R7P]);
140 
141 	/* make sure we use R7 "non-prime" on ESCC */
142 	write_zsreg(uap, R15, regs[R15] & ~EN85C30);
143 
144 	/* Synchronous mode config.  */
145 	write_zsreg(uap, R6, regs[R6]);
146 	write_zsreg(uap, R7, regs[R7]);
147 
148 	/* Disable baud generator.  */
149 	write_zsreg(uap, R14, regs[R14] & ~BRENAB);
150 
151 	/* Clock mode control.  */
152 	write_zsreg(uap, R11, regs[R11]);
153 
154 	/* Lower and upper byte of baud rate generator divisor.  */
155 	write_zsreg(uap, R12, regs[R12]);
156 	write_zsreg(uap, R13, regs[R13]);
157 
158 	/* Now rewrite R14, with BRENAB (if set).  */
159 	write_zsreg(uap, R14, regs[R14]);
160 
161 	/* Reset external status interrupts.  */
162 	write_zsreg(uap, R0, RES_EXT_INT);
163 	write_zsreg(uap, R0, RES_EXT_INT);
164 
165 	/* Rewrite R3/R5, this time without enables masked.  */
166 	write_zsreg(uap, R3, regs[R3]);
167 	write_zsreg(uap, R5, regs[R5]);
168 
169 	/* Rewrite R1, this time without IRQ enabled masked.  */
170 	write_zsreg(uap, R1, regs[R1]);
171 
172 	/* Enable interrupts */
173 	write_zsreg(uap, R9, regs[R9]);
174 }
175 
176 /*
177  * We do like sunzilog to avoid disrupting pending Tx
178  * Reprogram the Zilog channel HW registers with the copies found in the
179  * software state struct.  If the transmitter is busy, we defer this update
180  * until the next TX complete interrupt.  Else, we do it right now.
181  *
182  * The UART port lock must be held and local interrupts disabled.
183  */
184 static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
185 {
186 	if (!ZS_REGS_HELD(uap)) {
187 		if (ZS_TX_ACTIVE(uap)) {
188 			uap->flags |= PMACZILOG_FLAG_REGS_HELD;
189 		} else {
190 			pmz_debug("pmz: maybe_update_regs: updating\n");
191 			pmz_load_zsregs(uap, uap->curregs);
192 		}
193 	}
194 }
195 
196 static void pmz_interrupt_control(struct uart_pmac_port *uap, int enable)
197 {
198 	if (enable) {
199 		uap->curregs[1] |= INT_ALL_Rx | TxINT_ENAB;
200 		if (!ZS_IS_EXTCLK(uap))
201 			uap->curregs[1] |= EXT_INT_ENAB;
202 	} else {
203 		uap->curregs[1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
204 	}
205 	write_zsreg(uap, R1, uap->curregs[1]);
206 }
207 
208 static bool pmz_receive_chars(struct uart_pmac_port *uap)
209 	__must_hold(&uap->port.lock)
210 {
211 	struct tty_port *port;
212 	unsigned char ch, r1, drop, flag;
213 	int loops = 0;
214 
215 	/* Sanity check, make sure the old bug is no longer happening */
216 	if (uap->port.state == NULL) {
217 		WARN_ON(1);
218 		(void)read_zsdata(uap);
219 		return false;
220 	}
221 	port = &uap->port.state->port;
222 
223 	while (1) {
224 		drop = 0;
225 
226 		r1 = read_zsreg(uap, R1);
227 		ch = read_zsdata(uap);
228 
229 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
230 			write_zsreg(uap, R0, ERR_RES);
231 			zssync(uap);
232 		}
233 
234 		ch &= uap->parity_mask;
235 		if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
236 			uap->flags &= ~PMACZILOG_FLAG_BREAK;
237 		}
238 
239 #if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
240 #ifdef USE_CTRL_O_SYSRQ
241 		/* Handle the SysRq ^O Hack */
242 		if (ch == '\x0f') {
243 			uap->port.sysrq = jiffies + HZ*5;
244 			goto next_char;
245 		}
246 #endif /* USE_CTRL_O_SYSRQ */
247 		if (uap->port.sysrq) {
248 			int swallow;
249 			spin_unlock(&uap->port.lock);
250 			swallow = uart_handle_sysrq_char(&uap->port, ch);
251 			spin_lock(&uap->port.lock);
252 			if (swallow)
253 				goto next_char;
254 		}
255 #endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
256 
257 		/* A real serial line, record the character and status.  */
258 		if (drop)
259 			goto next_char;
260 
261 		flag = TTY_NORMAL;
262 		uap->port.icount.rx++;
263 
264 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
265 			if (r1 & BRK_ABRT) {
266 				pmz_debug("pmz: got break !\n");
267 				r1 &= ~(PAR_ERR | CRC_ERR);
268 				uap->port.icount.brk++;
269 				if (uart_handle_break(&uap->port))
270 					goto next_char;
271 			}
272 			else if (r1 & PAR_ERR)
273 				uap->port.icount.parity++;
274 			else if (r1 & CRC_ERR)
275 				uap->port.icount.frame++;
276 			if (r1 & Rx_OVR)
277 				uap->port.icount.overrun++;
278 			r1 &= uap->port.read_status_mask;
279 			if (r1 & BRK_ABRT)
280 				flag = TTY_BREAK;
281 			else if (r1 & PAR_ERR)
282 				flag = TTY_PARITY;
283 			else if (r1 & CRC_ERR)
284 				flag = TTY_FRAME;
285 		}
286 
287 		if (uap->port.ignore_status_mask == 0xff ||
288 		    (r1 & uap->port.ignore_status_mask) == 0) {
289 			tty_insert_flip_char(port, ch, flag);
290 		}
291 		if (r1 & Rx_OVR)
292 			tty_insert_flip_char(port, 0, TTY_OVERRUN);
293 	next_char:
294 		/* We can get stuck in an infinite loop getting char 0 when the
295 		 * line is in a wrong HW state, we break that here.
296 		 * When that happens, I disable the receive side of the driver.
297 		 * Note that what I've been experiencing is a real irq loop where
298 		 * I'm getting flooded regardless of the actual port speed.
299 		 * Something strange is going on with the HW
300 		 */
301 		if ((++loops) > 1000)
302 			goto flood;
303 		ch = read_zsreg(uap, R0);
304 		if (!(ch & Rx_CH_AV))
305 			break;
306 	}
307 
308 	return true;
309  flood:
310 	pmz_interrupt_control(uap, 0);
311 	pmz_error("pmz: rx irq flood !\n");
312 	return true;
313 }
314 
315 static void pmz_status_handle(struct uart_pmac_port *uap)
316 {
317 	unsigned char status;
318 
319 	status = read_zsreg(uap, R0);
320 	write_zsreg(uap, R0, RES_EXT_INT);
321 	zssync(uap);
322 
323 	if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
324 		if (status & SYNC_HUNT)
325 			uap->port.icount.dsr++;
326 
327 		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
328 		 * But it does not tell us which bit has changed, we have to keep
329 		 * track of this ourselves.
330 		 * The CTS input is inverted for some reason.  -- paulus
331 		 */
332 		if ((status ^ uap->prev_status) & DCD)
333 			uart_handle_dcd_change(&uap->port,
334 					       (status & DCD));
335 		if ((status ^ uap->prev_status) & CTS)
336 			uart_handle_cts_change(&uap->port,
337 					       !(status & CTS));
338 
339 		wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
340 	}
341 
342 	if (status & BRK_ABRT)
343 		uap->flags |= PMACZILOG_FLAG_BREAK;
344 
345 	uap->prev_status = status;
346 }
347 
348 static void pmz_transmit_chars(struct uart_pmac_port *uap)
349 {
350 	struct circ_buf *xmit;
351 
352 	if (ZS_IS_CONS(uap)) {
353 		unsigned char status = read_zsreg(uap, R0);
354 
355 		/* TX still busy?  Just wait for the next TX done interrupt.
356 		 *
357 		 * It can occur because of how we do serial console writes.  It would
358 		 * be nice to transmit console writes just like we normally would for
359 		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not
360 		 * easy because console writes cannot sleep.  One solution might be
361 		 * to poll on enough port->xmit space becoming free.  -DaveM
362 		 */
363 		if (!(status & Tx_BUF_EMP))
364 			return;
365 	}
366 
367 	uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
368 
369 	if (ZS_REGS_HELD(uap)) {
370 		pmz_load_zsregs(uap, uap->curregs);
371 		uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
372 	}
373 
374 	if (ZS_TX_STOPPED(uap)) {
375 		uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
376 		goto ack_tx_int;
377 	}
378 
379 	/* Under some circumstances, we see interrupts reported for
380 	 * a closed channel. The interrupt mask in R1 is clear, but
381 	 * R3 still signals the interrupts and we see them when taking
382 	 * an interrupt for the other channel (this could be a qemu
383 	 * bug but since the ESCC doc doesn't specify precsiely whether
384 	 * R3 interrup status bits are masked by R1 interrupt enable
385 	 * bits, better safe than sorry). --BenH.
386 	 */
387 	if (!ZS_IS_OPEN(uap))
388 		goto ack_tx_int;
389 
390 	if (uap->port.x_char) {
391 		uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
392 		write_zsdata(uap, uap->port.x_char);
393 		zssync(uap);
394 		uap->port.icount.tx++;
395 		uap->port.x_char = 0;
396 		return;
397 	}
398 
399 	if (uap->port.state == NULL)
400 		goto ack_tx_int;
401 	xmit = &uap->port.state->xmit;
402 	if (uart_circ_empty(xmit)) {
403 		uart_write_wakeup(&uap->port);
404 		goto ack_tx_int;
405 	}
406 	if (uart_tx_stopped(&uap->port))
407 		goto ack_tx_int;
408 
409 	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
410 	write_zsdata(uap, xmit->buf[xmit->tail]);
411 	zssync(uap);
412 
413 	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
414 	uap->port.icount.tx++;
415 
416 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
417 		uart_write_wakeup(&uap->port);
418 
419 	return;
420 
421 ack_tx_int:
422 	write_zsreg(uap, R0, RES_Tx_P);
423 	zssync(uap);
424 }
425 
426 /* Hrm... we register that twice, fixme later.... */
427 static irqreturn_t pmz_interrupt(int irq, void *dev_id)
428 {
429 	struct uart_pmac_port *uap = dev_id;
430 	struct uart_pmac_port *uap_a;
431 	struct uart_pmac_port *uap_b;
432 	int rc = IRQ_NONE;
433 	bool push;
434 	u8 r3;
435 
436 	uap_a = pmz_get_port_A(uap);
437 	uap_b = uap_a->mate;
438 
439 	spin_lock(&uap_a->port.lock);
440 	r3 = read_zsreg(uap_a, R3);
441 
442 	/* Channel A */
443 	push = false;
444 	if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
445 		if (!ZS_IS_OPEN(uap_a)) {
446 			pmz_debug("ChanA interrupt while not open !\n");
447 			goto skip_a;
448 		}
449 		write_zsreg(uap_a, R0, RES_H_IUS);
450 		zssync(uap_a);
451 		if (r3 & CHAEXT)
452 			pmz_status_handle(uap_a);
453 		if (r3 & CHARxIP)
454 			push = pmz_receive_chars(uap_a);
455 		if (r3 & CHATxIP)
456 			pmz_transmit_chars(uap_a);
457 		rc = IRQ_HANDLED;
458 	}
459  skip_a:
460 	spin_unlock(&uap_a->port.lock);
461 	if (push)
462 		tty_flip_buffer_push(&uap->port.state->port);
463 
464 	if (!uap_b)
465 		goto out;
466 
467 	spin_lock(&uap_b->port.lock);
468 	push = false;
469 	if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
470 		if (!ZS_IS_OPEN(uap_b)) {
471 			pmz_debug("ChanB interrupt while not open !\n");
472 			goto skip_b;
473 		}
474 		write_zsreg(uap_b, R0, RES_H_IUS);
475 		zssync(uap_b);
476 		if (r3 & CHBEXT)
477 			pmz_status_handle(uap_b);
478 		if (r3 & CHBRxIP)
479 			push = pmz_receive_chars(uap_b);
480 		if (r3 & CHBTxIP)
481 			pmz_transmit_chars(uap_b);
482 		rc = IRQ_HANDLED;
483 	}
484  skip_b:
485 	spin_unlock(&uap_b->port.lock);
486 	if (push)
487 		tty_flip_buffer_push(&uap->port.state->port);
488 
489  out:
490 	return rc;
491 }
492 
493 /*
494  * Peek the status register, lock not held by caller
495  */
496 static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
497 {
498 	unsigned long flags;
499 	u8 status;
500 
501 	spin_lock_irqsave(&uap->port.lock, flags);
502 	status = read_zsreg(uap, R0);
503 	spin_unlock_irqrestore(&uap->port.lock, flags);
504 
505 	return status;
506 }
507 
508 /*
509  * Check if transmitter is empty
510  * The port lock is not held.
511  */
512 static unsigned int pmz_tx_empty(struct uart_port *port)
513 {
514 	unsigned char status;
515 
516 	status = pmz_peek_status(to_pmz(port));
517 	if (status & Tx_BUF_EMP)
518 		return TIOCSER_TEMT;
519 	return 0;
520 }
521 
522 /*
523  * Set Modem Control (RTS & DTR) bits
524  * The port lock is held and interrupts are disabled.
525  * Note: Shall we really filter out RTS on external ports or
526  * should that be dealt at higher level only ?
527  */
528 static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
529 {
530 	struct uart_pmac_port *uap = to_pmz(port);
531 	unsigned char set_bits, clear_bits;
532 
533         /* Do nothing for irda for now... */
534 	if (ZS_IS_IRDA(uap))
535 		return;
536 	/* We get called during boot with a port not up yet */
537 	if (!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
538 		return;
539 
540 	set_bits = clear_bits = 0;
541 
542 	if (ZS_IS_INTMODEM(uap)) {
543 		if (mctrl & TIOCM_RTS)
544 			set_bits |= RTS;
545 		else
546 			clear_bits |= RTS;
547 	}
548 	if (mctrl & TIOCM_DTR)
549 		set_bits |= DTR;
550 	else
551 		clear_bits |= DTR;
552 
553 	/* NOTE: Not subject to 'transmitter active' rule.  */
554 	uap->curregs[R5] |= set_bits;
555 	uap->curregs[R5] &= ~clear_bits;
556 
557 	write_zsreg(uap, R5, uap->curregs[R5]);
558 	pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
559 		  set_bits, clear_bits, uap->curregs[R5]);
560 	zssync(uap);
561 }
562 
563 /*
564  * Get Modem Control bits (only the input ones, the core will
565  * or that with a cached value of the control ones)
566  * The port lock is held and interrupts are disabled.
567  */
568 static unsigned int pmz_get_mctrl(struct uart_port *port)
569 {
570 	struct uart_pmac_port *uap = to_pmz(port);
571 	unsigned char status;
572 	unsigned int ret;
573 
574 	status = read_zsreg(uap, R0);
575 
576 	ret = 0;
577 	if (status & DCD)
578 		ret |= TIOCM_CAR;
579 	if (status & SYNC_HUNT)
580 		ret |= TIOCM_DSR;
581 	if (!(status & CTS))
582 		ret |= TIOCM_CTS;
583 
584 	return ret;
585 }
586 
587 /*
588  * Stop TX side. Dealt like sunzilog at next Tx interrupt,
589  * though for DMA, we will have to do a bit more.
590  * The port lock is held and interrupts are disabled.
591  */
592 static void pmz_stop_tx(struct uart_port *port)
593 {
594 	to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
595 }
596 
597 /*
598  * Kick the Tx side.
599  * The port lock is held and interrupts are disabled.
600  */
601 static void pmz_start_tx(struct uart_port *port)
602 {
603 	struct uart_pmac_port *uap = to_pmz(port);
604 	unsigned char status;
605 
606 	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
607 	uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
608 
609 	status = read_zsreg(uap, R0);
610 
611 	/* TX busy?  Just wait for the TX done interrupt.  */
612 	if (!(status & Tx_BUF_EMP))
613 		return;
614 
615 	/* Send the first character to jump-start the TX done
616 	 * IRQ sending engine.
617 	 */
618 	if (port->x_char) {
619 		write_zsdata(uap, port->x_char);
620 		zssync(uap);
621 		port->icount.tx++;
622 		port->x_char = 0;
623 	} else {
624 		struct circ_buf *xmit = &port->state->xmit;
625 
626 		if (uart_circ_empty(xmit))
627 			return;
628 		write_zsdata(uap, xmit->buf[xmit->tail]);
629 		zssync(uap);
630 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
631 		port->icount.tx++;
632 
633 		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
634 			uart_write_wakeup(&uap->port);
635 	}
636 }
637 
638 /*
639  * Stop Rx side, basically disable emitting of
640  * Rx interrupts on the port. We don't disable the rx
641  * side of the chip proper though
642  * The port lock is held.
643  */
644 static void pmz_stop_rx(struct uart_port *port)
645 {
646 	struct uart_pmac_port *uap = to_pmz(port);
647 
648 	/* Disable all RX interrupts.  */
649 	uap->curregs[R1] &= ~RxINT_MASK;
650 	pmz_maybe_update_regs(uap);
651 }
652 
653 /*
654  * Enable modem status change interrupts
655  * The port lock is held.
656  */
657 static void pmz_enable_ms(struct uart_port *port)
658 {
659 	struct uart_pmac_port *uap = to_pmz(port);
660 	unsigned char new_reg;
661 
662 	if (ZS_IS_IRDA(uap))
663 		return;
664 	new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
665 	if (new_reg != uap->curregs[R15]) {
666 		uap->curregs[R15] = new_reg;
667 
668 		/* NOTE: Not subject to 'transmitter active' rule. */
669 		write_zsreg(uap, R15, uap->curregs[R15]);
670 	}
671 }
672 
673 /*
674  * Control break state emission
675  * The port lock is not held.
676  */
677 static void pmz_break_ctl(struct uart_port *port, int break_state)
678 {
679 	struct uart_pmac_port *uap = to_pmz(port);
680 	unsigned char set_bits, clear_bits, new_reg;
681 	unsigned long flags;
682 
683 	set_bits = clear_bits = 0;
684 
685 	if (break_state)
686 		set_bits |= SND_BRK;
687 	else
688 		clear_bits |= SND_BRK;
689 
690 	spin_lock_irqsave(&port->lock, flags);
691 
692 	new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
693 	if (new_reg != uap->curregs[R5]) {
694 		uap->curregs[R5] = new_reg;
695 		write_zsreg(uap, R5, uap->curregs[R5]);
696 	}
697 
698 	spin_unlock_irqrestore(&port->lock, flags);
699 }
700 
701 #ifdef CONFIG_PPC_PMAC
702 
703 /*
704  * Turn power on or off to the SCC and associated stuff
705  * (port drivers, modem, IR port, etc.)
706  * Returns the number of milliseconds we should wait before
707  * trying to use the port.
708  */
709 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
710 {
711 	int delay = 0;
712 	int rc;
713 
714 	if (state) {
715 		rc = pmac_call_feature(
716 			PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
717 		pmz_debug("port power on result: %d\n", rc);
718 		if (ZS_IS_INTMODEM(uap)) {
719 			rc = pmac_call_feature(
720 				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
721 			delay = 2500;	/* wait for 2.5s before using */
722 			pmz_debug("modem power result: %d\n", rc);
723 		}
724 	} else {
725 		/* TODO: Make that depend on a timer, don't power down
726 		 * immediately
727 		 */
728 		if (ZS_IS_INTMODEM(uap)) {
729 			rc = pmac_call_feature(
730 				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
731 			pmz_debug("port power off result: %d\n", rc);
732 		}
733 		pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
734 	}
735 	return delay;
736 }
737 
738 #else
739 
740 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
741 {
742 	return 0;
743 }
744 
745 #endif /* !CONFIG_PPC_PMAC */
746 
747 /*
748  * FixZeroBug....Works around a bug in the SCC receiving channel.
749  * Inspired from Darwin code, 15 Sept. 2000  -DanM
750  *
751  * The following sequence prevents a problem that is seen with O'Hare ASICs
752  * (most versions -- also with some Heathrow and Hydra ASICs) where a zero
753  * at the input to the receiver becomes 'stuck' and locks up the receiver.
754  * This problem can occur as a result of a zero bit at the receiver input
755  * coincident with any of the following events:
756  *
757  *	The SCC is initialized (hardware or software).
758  *	A framing error is detected.
759  *	The clocking option changes from synchronous or X1 asynchronous
760  *		clocking to X16, X32, or X64 asynchronous clocking.
761  *	The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
762  *
763  * This workaround attempts to recover from the lockup condition by placing
764  * the SCC in synchronous loopback mode with a fast clock before programming
765  * any of the asynchronous modes.
766  */
767 static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
768 {
769 	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
770 	zssync(uap);
771 	udelay(10);
772 	write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
773 	zssync(uap);
774 
775 	write_zsreg(uap, 4, X1CLK | MONSYNC);
776 	write_zsreg(uap, 3, Rx8);
777 	write_zsreg(uap, 5, Tx8 | RTS);
778 	write_zsreg(uap, 9, NV);	/* Didn't we already do this? */
779 	write_zsreg(uap, 11, RCBR | TCBR);
780 	write_zsreg(uap, 12, 0);
781 	write_zsreg(uap, 13, 0);
782 	write_zsreg(uap, 14, (LOOPBAK | BRSRC));
783 	write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
784 	write_zsreg(uap, 3, Rx8 | RxENABLE);
785 	write_zsreg(uap, 0, RES_EXT_INT);
786 	write_zsreg(uap, 0, RES_EXT_INT);
787 	write_zsreg(uap, 0, RES_EXT_INT);	/* to kill some time */
788 
789 	/* The channel should be OK now, but it is probably receiving
790 	 * loopback garbage.
791 	 * Switch to asynchronous mode, disable the receiver,
792 	 * and discard everything in the receive buffer.
793 	 */
794 	write_zsreg(uap, 9, NV);
795 	write_zsreg(uap, 4, X16CLK | SB_MASK);
796 	write_zsreg(uap, 3, Rx8);
797 
798 	while (read_zsreg(uap, 0) & Rx_CH_AV) {
799 		(void)read_zsreg(uap, 8);
800 		write_zsreg(uap, 0, RES_EXT_INT);
801 		write_zsreg(uap, 0, ERR_RES);
802 	}
803 }
804 
805 /*
806  * Real startup routine, powers up the hardware and sets up
807  * the SCC. Returns a delay in ms where you need to wait before
808  * actually using the port, this is typically the internal modem
809  * powerup delay. This routine expect the lock to be taken.
810  */
811 static int __pmz_startup(struct uart_pmac_port *uap)
812 {
813 	int pwr_delay = 0;
814 
815 	memset(&uap->curregs, 0, sizeof(uap->curregs));
816 
817 	/* Power up the SCC & underlying hardware (modem/irda) */
818 	pwr_delay = pmz_set_scc_power(uap, 1);
819 
820 	/* Nice buggy HW ... */
821 	pmz_fix_zero_bug_scc(uap);
822 
823 	/* Reset the channel */
824 	uap->curregs[R9] = 0;
825 	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
826 	zssync(uap);
827 	udelay(10);
828 	write_zsreg(uap, 9, 0);
829 	zssync(uap);
830 
831 	/* Clear the interrupt registers */
832 	write_zsreg(uap, R1, 0);
833 	write_zsreg(uap, R0, ERR_RES);
834 	write_zsreg(uap, R0, ERR_RES);
835 	write_zsreg(uap, R0, RES_H_IUS);
836 	write_zsreg(uap, R0, RES_H_IUS);
837 
838 	/* Setup some valid baud rate */
839 	uap->curregs[R4] = X16CLK | SB1;
840 	uap->curregs[R3] = Rx8;
841 	uap->curregs[R5] = Tx8 | RTS;
842 	if (!ZS_IS_IRDA(uap))
843 		uap->curregs[R5] |= DTR;
844 	uap->curregs[R12] = 0;
845 	uap->curregs[R13] = 0;
846 	uap->curregs[R14] = BRENAB;
847 
848 	/* Clear handshaking, enable BREAK interrupts */
849 	uap->curregs[R15] = BRKIE;
850 
851 	/* Master interrupt enable */
852 	uap->curregs[R9] |= NV | MIE;
853 
854 	pmz_load_zsregs(uap, uap->curregs);
855 
856 	/* Enable receiver and transmitter.  */
857 	write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
858 	write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
859 
860 	/* Remember status for DCD/CTS changes */
861 	uap->prev_status = read_zsreg(uap, R0);
862 
863 	return pwr_delay;
864 }
865 
866 static void pmz_irda_reset(struct uart_pmac_port *uap)
867 {
868 	unsigned long flags;
869 
870 	spin_lock_irqsave(&uap->port.lock, flags);
871 	uap->curregs[R5] |= DTR;
872 	write_zsreg(uap, R5, uap->curregs[R5]);
873 	zssync(uap);
874 	spin_unlock_irqrestore(&uap->port.lock, flags);
875 	msleep(110);
876 
877 	spin_lock_irqsave(&uap->port.lock, flags);
878 	uap->curregs[R5] &= ~DTR;
879 	write_zsreg(uap, R5, uap->curregs[R5]);
880 	zssync(uap);
881 	spin_unlock_irqrestore(&uap->port.lock, flags);
882 	msleep(10);
883 }
884 
885 /*
886  * This is the "normal" startup routine, using the above one
887  * wrapped with the lock and doing a schedule delay
888  */
889 static int pmz_startup(struct uart_port *port)
890 {
891 	struct uart_pmac_port *uap = to_pmz(port);
892 	unsigned long flags;
893 	int pwr_delay = 0;
894 
895 	uap->flags |= PMACZILOG_FLAG_IS_OPEN;
896 
897 	/* A console is never powered down. Else, power up and
898 	 * initialize the chip
899 	 */
900 	if (!ZS_IS_CONS(uap)) {
901 		spin_lock_irqsave(&port->lock, flags);
902 		pwr_delay = __pmz_startup(uap);
903 		spin_unlock_irqrestore(&port->lock, flags);
904 	}
905 	sprintf(uap->irq_name, PMACZILOG_NAME"%d", uap->port.line);
906 	if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,
907 			uap->irq_name, uap)) {
908 		pmz_error("Unable to register zs interrupt handler.\n");
909 		pmz_set_scc_power(uap, 0);
910 		return -ENXIO;
911 	}
912 
913 	/* Right now, we deal with delay by blocking here, I'll be
914 	 * smarter later on
915 	 */
916 	if (pwr_delay != 0) {
917 		pmz_debug("pmz: delaying %d ms\n", pwr_delay);
918 		msleep(pwr_delay);
919 	}
920 
921 	/* IrDA reset is done now */
922 	if (ZS_IS_IRDA(uap))
923 		pmz_irda_reset(uap);
924 
925 	/* Enable interrupt requests for the channel */
926 	spin_lock_irqsave(&port->lock, flags);
927 	pmz_interrupt_control(uap, 1);
928 	spin_unlock_irqrestore(&port->lock, flags);
929 
930 	return 0;
931 }
932 
933 static void pmz_shutdown(struct uart_port *port)
934 {
935 	struct uart_pmac_port *uap = to_pmz(port);
936 	unsigned long flags;
937 
938 	spin_lock_irqsave(&port->lock, flags);
939 
940 	/* Disable interrupt requests for the channel */
941 	pmz_interrupt_control(uap, 0);
942 
943 	if (!ZS_IS_CONS(uap)) {
944 		/* Disable receiver and transmitter */
945 		uap->curregs[R3] &= ~RxENABLE;
946 		uap->curregs[R5] &= ~TxENABLE;
947 
948 		/* Disable break assertion */
949 		uap->curregs[R5] &= ~SND_BRK;
950 		pmz_maybe_update_regs(uap);
951 	}
952 
953 	spin_unlock_irqrestore(&port->lock, flags);
954 
955 	/* Release interrupt handler */
956 	free_irq(uap->port.irq, uap);
957 
958 	spin_lock_irqsave(&port->lock, flags);
959 
960 	uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
961 
962 	if (!ZS_IS_CONS(uap))
963 		pmz_set_scc_power(uap, 0);	/* Shut the chip down */
964 
965 	spin_unlock_irqrestore(&port->lock, flags);
966 }
967 
968 /* Shared by TTY driver and serial console setup.  The port lock is held
969  * and local interrupts are disabled.
970  */
971 static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
972 			      unsigned int iflag, unsigned long baud)
973 {
974 	int brg;
975 
976 	/* Switch to external clocking for IrDA high clock rates. That
977 	 * code could be re-used for Midi interfaces with different
978 	 * multipliers
979 	 */
980 	if (baud >= 115200 && ZS_IS_IRDA(uap)) {
981 		uap->curregs[R4] = X1CLK;
982 		uap->curregs[R11] = RCTRxCP | TCTRxCP;
983 		uap->curregs[R14] = 0; /* BRG off */
984 		uap->curregs[R12] = 0;
985 		uap->curregs[R13] = 0;
986 		uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
987 	} else {
988 		switch (baud) {
989 		case ZS_CLOCK/16:	/* 230400 */
990 			uap->curregs[R4] = X16CLK;
991 			uap->curregs[R11] = 0;
992 			uap->curregs[R14] = 0;
993 			break;
994 		case ZS_CLOCK/32:	/* 115200 */
995 			uap->curregs[R4] = X32CLK;
996 			uap->curregs[R11] = 0;
997 			uap->curregs[R14] = 0;
998 			break;
999 		default:
1000 			uap->curregs[R4] = X16CLK;
1001 			uap->curregs[R11] = TCBR | RCBR;
1002 			brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
1003 			uap->curregs[R12] = (brg & 255);
1004 			uap->curregs[R13] = ((brg >> 8) & 255);
1005 			uap->curregs[R14] = BRENAB;
1006 		}
1007 		uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
1008 	}
1009 
1010 	/* Character size, stop bits, and parity. */
1011 	uap->curregs[3] &= ~RxN_MASK;
1012 	uap->curregs[5] &= ~TxN_MASK;
1013 
1014 	switch (cflag & CSIZE) {
1015 	case CS5:
1016 		uap->curregs[3] |= Rx5;
1017 		uap->curregs[5] |= Tx5;
1018 		uap->parity_mask = 0x1f;
1019 		break;
1020 	case CS6:
1021 		uap->curregs[3] |= Rx6;
1022 		uap->curregs[5] |= Tx6;
1023 		uap->parity_mask = 0x3f;
1024 		break;
1025 	case CS7:
1026 		uap->curregs[3] |= Rx7;
1027 		uap->curregs[5] |= Tx7;
1028 		uap->parity_mask = 0x7f;
1029 		break;
1030 	case CS8:
1031 	default:
1032 		uap->curregs[3] |= Rx8;
1033 		uap->curregs[5] |= Tx8;
1034 		uap->parity_mask = 0xff;
1035 		break;
1036 	}
1037 	uap->curregs[4] &= ~(SB_MASK);
1038 	if (cflag & CSTOPB)
1039 		uap->curregs[4] |= SB2;
1040 	else
1041 		uap->curregs[4] |= SB1;
1042 	if (cflag & PARENB)
1043 		uap->curregs[4] |= PAR_ENAB;
1044 	else
1045 		uap->curregs[4] &= ~PAR_ENAB;
1046 	if (!(cflag & PARODD))
1047 		uap->curregs[4] |= PAR_EVEN;
1048 	else
1049 		uap->curregs[4] &= ~PAR_EVEN;
1050 
1051 	uap->port.read_status_mask = Rx_OVR;
1052 	if (iflag & INPCK)
1053 		uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
1054 	if (iflag & (IGNBRK | BRKINT | PARMRK))
1055 		uap->port.read_status_mask |= BRK_ABRT;
1056 
1057 	uap->port.ignore_status_mask = 0;
1058 	if (iflag & IGNPAR)
1059 		uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
1060 	if (iflag & IGNBRK) {
1061 		uap->port.ignore_status_mask |= BRK_ABRT;
1062 		if (iflag & IGNPAR)
1063 			uap->port.ignore_status_mask |= Rx_OVR;
1064 	}
1065 
1066 	if ((cflag & CREAD) == 0)
1067 		uap->port.ignore_status_mask = 0xff;
1068 }
1069 
1070 
1071 /*
1072  * Set the irda codec on the imac to the specified baud rate.
1073  */
1074 static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
1075 {
1076 	u8 cmdbyte;
1077 	int t, version;
1078 
1079 	switch (*baud) {
1080 	/* SIR modes */
1081 	case 2400:
1082 		cmdbyte = 0x53;
1083 		break;
1084 	case 4800:
1085 		cmdbyte = 0x52;
1086 		break;
1087 	case 9600:
1088 		cmdbyte = 0x51;
1089 		break;
1090 	case 19200:
1091 		cmdbyte = 0x50;
1092 		break;
1093 	case 38400:
1094 		cmdbyte = 0x4f;
1095 		break;
1096 	case 57600:
1097 		cmdbyte = 0x4e;
1098 		break;
1099 	case 115200:
1100 		cmdbyte = 0x4d;
1101 		break;
1102 	/* The FIR modes aren't really supported at this point, how
1103 	 * do we select the speed ? via the FCR on KeyLargo ?
1104 	 */
1105 	case 1152000:
1106 		cmdbyte = 0;
1107 		break;
1108 	case 4000000:
1109 		cmdbyte = 0;
1110 		break;
1111 	default: /* 9600 */
1112 		cmdbyte = 0x51;
1113 		*baud = 9600;
1114 		break;
1115 	}
1116 
1117 	/* Wait for transmitter to drain */
1118 	t = 10000;
1119 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
1120 	       || (read_zsreg(uap, R1) & ALL_SNT) == 0) {
1121 		if (--t <= 0) {
1122 			pmz_error("transmitter didn't drain\n");
1123 			return;
1124 		}
1125 		udelay(10);
1126 	}
1127 
1128 	/* Drain the receiver too */
1129 	t = 100;
1130 	(void)read_zsdata(uap);
1131 	(void)read_zsdata(uap);
1132 	(void)read_zsdata(uap);
1133 	mdelay(10);
1134 	while (read_zsreg(uap, R0) & Rx_CH_AV) {
1135 		read_zsdata(uap);
1136 		mdelay(10);
1137 		if (--t <= 0) {
1138 			pmz_error("receiver didn't drain\n");
1139 			return;
1140 		}
1141 	}
1142 
1143 	/* Switch to command mode */
1144 	uap->curregs[R5] |= DTR;
1145 	write_zsreg(uap, R5, uap->curregs[R5]);
1146 	zssync(uap);
1147 	mdelay(1);
1148 
1149 	/* Switch SCC to 19200 */
1150 	pmz_convert_to_zs(uap, CS8, 0, 19200);
1151 	pmz_load_zsregs(uap, uap->curregs);
1152 	mdelay(1);
1153 
1154 	/* Write get_version command byte */
1155 	write_zsdata(uap, 1);
1156 	t = 5000;
1157 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1158 		if (--t <= 0) {
1159 			pmz_error("irda_setup timed out on get_version byte\n");
1160 			goto out;
1161 		}
1162 		udelay(10);
1163 	}
1164 	version = read_zsdata(uap);
1165 
1166 	if (version < 4) {
1167 		pmz_info("IrDA: dongle version %d not supported\n", version);
1168 		goto out;
1169 	}
1170 
1171 	/* Send speed mode */
1172 	write_zsdata(uap, cmdbyte);
1173 	t = 5000;
1174 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1175 		if (--t <= 0) {
1176 			pmz_error("irda_setup timed out on speed mode byte\n");
1177 			goto out;
1178 		}
1179 		udelay(10);
1180 	}
1181 	t = read_zsdata(uap);
1182 	if (t != cmdbyte)
1183 		pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
1184 
1185 	pmz_info("IrDA setup for %ld bps, dongle version: %d\n",
1186 		 *baud, version);
1187 
1188 	(void)read_zsdata(uap);
1189 	(void)read_zsdata(uap);
1190 	(void)read_zsdata(uap);
1191 
1192  out:
1193 	/* Switch back to data mode */
1194 	uap->curregs[R5] &= ~DTR;
1195 	write_zsreg(uap, R5, uap->curregs[R5]);
1196 	zssync(uap);
1197 
1198 	(void)read_zsdata(uap);
1199 	(void)read_zsdata(uap);
1200 	(void)read_zsdata(uap);
1201 }
1202 
1203 
1204 static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1205 			      const struct ktermios *old)
1206 {
1207 	struct uart_pmac_port *uap = to_pmz(port);
1208 	unsigned long baud;
1209 
1210 	/* XXX Check which revs of machines actually allow 1 and 4Mb speeds
1211 	 * on the IR dongle. Note that the IRTTY driver currently doesn't know
1212 	 * about the FIR mode and high speed modes. So these are unused. For
1213 	 * implementing proper support for these, we should probably add some
1214 	 * DMA as well, at least on the Rx side, which isn't a simple thing
1215 	 * at this point.
1216 	 */
1217 	if (ZS_IS_IRDA(uap)) {
1218 		/* Calc baud rate */
1219 		baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
1220 		pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
1221 		/* Cet the irda codec to the right rate */
1222 		pmz_irda_setup(uap, &baud);
1223 		/* Set final baud rate */
1224 		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1225 		pmz_load_zsregs(uap, uap->curregs);
1226 		zssync(uap);
1227 	} else {
1228 		baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
1229 		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1230 		/* Make sure modem status interrupts are correctly configured */
1231 		if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
1232 			uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
1233 			uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
1234 		} else {
1235 			uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
1236 			uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
1237 		}
1238 
1239 		/* Load registers to the chip */
1240 		pmz_maybe_update_regs(uap);
1241 	}
1242 	uart_update_timeout(port, termios->c_cflag, baud);
1243 }
1244 
1245 /* The port lock is not held.  */
1246 static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1247 			    const struct ktermios *old)
1248 {
1249 	struct uart_pmac_port *uap = to_pmz(port);
1250 	unsigned long flags;
1251 
1252 	spin_lock_irqsave(&port->lock, flags);
1253 
1254 	/* Disable IRQs on the port */
1255 	pmz_interrupt_control(uap, 0);
1256 
1257 	/* Setup new port configuration */
1258 	__pmz_set_termios(port, termios, old);
1259 
1260 	/* Re-enable IRQs on the port */
1261 	if (ZS_IS_OPEN(uap))
1262 		pmz_interrupt_control(uap, 1);
1263 
1264 	spin_unlock_irqrestore(&port->lock, flags);
1265 }
1266 
1267 static const char *pmz_type(struct uart_port *port)
1268 {
1269 	struct uart_pmac_port *uap = to_pmz(port);
1270 
1271 	if (ZS_IS_IRDA(uap))
1272 		return "Z85c30 ESCC - Infrared port";
1273 	else if (ZS_IS_INTMODEM(uap))
1274 		return "Z85c30 ESCC - Internal modem";
1275 	return "Z85c30 ESCC - Serial port";
1276 }
1277 
1278 /* We do not request/release mappings of the registers here, this
1279  * happens at early serial probe time.
1280  */
1281 static void pmz_release_port(struct uart_port *port)
1282 {
1283 }
1284 
1285 static int pmz_request_port(struct uart_port *port)
1286 {
1287 	return 0;
1288 }
1289 
1290 /* These do not need to do anything interesting either.  */
1291 static void pmz_config_port(struct uart_port *port, int flags)
1292 {
1293 }
1294 
1295 /* We do not support letting the user mess with the divisor, IRQ, etc. */
1296 static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
1297 {
1298 	return -EINVAL;
1299 }
1300 
1301 #ifdef CONFIG_CONSOLE_POLL
1302 
1303 static int pmz_poll_get_char(struct uart_port *port)
1304 {
1305 	struct uart_pmac_port *uap =
1306 		container_of(port, struct uart_pmac_port, port);
1307 	int tries = 2;
1308 
1309 	while (tries) {
1310 		if ((read_zsreg(uap, R0) & Rx_CH_AV) != 0)
1311 			return read_zsdata(uap);
1312 		if (tries--)
1313 			udelay(5);
1314 	}
1315 
1316 	return NO_POLL_CHAR;
1317 }
1318 
1319 static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
1320 {
1321 	struct uart_pmac_port *uap =
1322 		container_of(port, struct uart_pmac_port, port);
1323 
1324 	/* Wait for the transmit buffer to empty. */
1325 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1326 		udelay(5);
1327 	write_zsdata(uap, c);
1328 }
1329 
1330 #endif /* CONFIG_CONSOLE_POLL */
1331 
1332 static const struct uart_ops pmz_pops = {
1333 	.tx_empty	=	pmz_tx_empty,
1334 	.set_mctrl	=	pmz_set_mctrl,
1335 	.get_mctrl	=	pmz_get_mctrl,
1336 	.stop_tx	=	pmz_stop_tx,
1337 	.start_tx	=	pmz_start_tx,
1338 	.stop_rx	=	pmz_stop_rx,
1339 	.enable_ms	=	pmz_enable_ms,
1340 	.break_ctl	=	pmz_break_ctl,
1341 	.startup	=	pmz_startup,
1342 	.shutdown	=	pmz_shutdown,
1343 	.set_termios	=	pmz_set_termios,
1344 	.type		=	pmz_type,
1345 	.release_port	=	pmz_release_port,
1346 	.request_port	=	pmz_request_port,
1347 	.config_port	=	pmz_config_port,
1348 	.verify_port	=	pmz_verify_port,
1349 #ifdef CONFIG_CONSOLE_POLL
1350 	.poll_get_char	=	pmz_poll_get_char,
1351 	.poll_put_char	=	pmz_poll_put_char,
1352 #endif
1353 };
1354 
1355 #ifdef CONFIG_PPC_PMAC
1356 
1357 /*
1358  * Setup one port structure after probing, HW is down at this point,
1359  * Unlike sunzilog, we don't need to pre-init the spinlock as we don't
1360  * register our console before uart_add_one_port() is called
1361  */
1362 static int __init pmz_init_port(struct uart_pmac_port *uap)
1363 {
1364 	struct device_node *np = uap->node;
1365 	const char *conn;
1366 	const struct slot_names_prop {
1367 		int	count;
1368 		char	name[1];
1369 	} *slots;
1370 	int len;
1371 	struct resource r_ports;
1372 
1373 	/*
1374 	 * Request & map chip registers
1375 	 */
1376 	if (of_address_to_resource(np, 0, &r_ports))
1377 		return -ENODEV;
1378 	uap->port.mapbase = r_ports.start;
1379 	uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
1380 
1381 	uap->control_reg = uap->port.membase;
1382 	uap->data_reg = uap->control_reg + 0x10;
1383 
1384 	/*
1385 	 * Detect port type
1386 	 */
1387 	if (of_device_is_compatible(np, "cobalt"))
1388 		uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1389 	conn = of_get_property(np, "AAPL,connector", &len);
1390 	if (conn && (strcmp(conn, "infrared") == 0))
1391 		uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1392 	uap->port_type = PMAC_SCC_ASYNC;
1393 	/* 1999 Powerbook G3 has slot-names property instead */
1394 	slots = of_get_property(np, "slot-names", &len);
1395 	if (slots && slots->count > 0) {
1396 		if (strcmp(slots->name, "IrDA") == 0)
1397 			uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1398 		else if (strcmp(slots->name, "Modem") == 0)
1399 			uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1400 	}
1401 	if (ZS_IS_IRDA(uap))
1402 		uap->port_type = PMAC_SCC_IRDA;
1403 	if (ZS_IS_INTMODEM(uap)) {
1404 		struct device_node* i2c_modem =
1405 			of_find_node_by_name(NULL, "i2c-modem");
1406 		if (i2c_modem) {
1407 			const char* mid =
1408 				of_get_property(i2c_modem, "modem-id", NULL);
1409 			if (mid) switch(*mid) {
1410 			case 0x04 :
1411 			case 0x05 :
1412 			case 0x07 :
1413 			case 0x08 :
1414 			case 0x0b :
1415 			case 0x0c :
1416 				uap->port_type = PMAC_SCC_I2S1;
1417 			}
1418 			printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
1419 				mid ? (*mid) : 0);
1420 			of_node_put(i2c_modem);
1421 		} else {
1422 			printk(KERN_INFO "pmac_zilog: serial modem detected\n");
1423 		}
1424 	}
1425 
1426 	/*
1427 	 * Init remaining bits of "port" structure
1428 	 */
1429 	uap->port.iotype = UPIO_MEM;
1430 	uap->port.irq = irq_of_parse_and_map(np, 0);
1431 	uap->port.uartclk = ZS_CLOCK;
1432 	uap->port.fifosize = 1;
1433 	uap->port.ops = &pmz_pops;
1434 	uap->port.type = PORT_PMAC_ZILOG;
1435 	uap->port.flags = 0;
1436 
1437 	/*
1438 	 * Fixup for the port on Gatwick for which the device-tree has
1439 	 * missing interrupts. Normally, the macio_dev would contain
1440 	 * fixed up interrupt info, but we use the device-tree directly
1441 	 * here due to early probing so we need the fixup too.
1442 	 */
1443 	if (uap->port.irq == 0 &&
1444 	    np->parent && np->parent->parent &&
1445 	    of_device_is_compatible(np->parent->parent, "gatwick")) {
1446 		/* IRQs on gatwick are offset by 64 */
1447 		uap->port.irq = irq_create_mapping(NULL, 64 + 15);
1448 	}
1449 
1450 	/* Setup some valid baud rate information in the register
1451 	 * shadows so we don't write crap there before baud rate is
1452 	 * first initialized.
1453 	 */
1454 	pmz_convert_to_zs(uap, CS8, 0, 9600);
1455 
1456 	return 0;
1457 }
1458 
1459 /*
1460  * Get rid of a port on module removal
1461  */
1462 static void pmz_dispose_port(struct uart_pmac_port *uap)
1463 {
1464 	struct device_node *np;
1465 
1466 	np = uap->node;
1467 	iounmap(uap->control_reg);
1468 	uap->node = NULL;
1469 	of_node_put(np);
1470 	memset(uap, 0, sizeof(struct uart_pmac_port));
1471 }
1472 
1473 /*
1474  * Called upon match with an escc node in the device-tree.
1475  */
1476 static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
1477 {
1478 	struct uart_pmac_port *uap;
1479 	int i;
1480 
1481 	/* Iterate the pmz_ports array to find a matching entry
1482 	 */
1483 	for (i = 0; i < MAX_ZS_PORTS; i++)
1484 		if (pmz_ports[i].node == mdev->ofdev.dev.of_node)
1485 			break;
1486 	if (i >= MAX_ZS_PORTS)
1487 		return -ENODEV;
1488 
1489 
1490 	uap = &pmz_ports[i];
1491 	uap->dev = mdev;
1492 	uap->port.dev = &mdev->ofdev.dev;
1493 	dev_set_drvdata(&mdev->ofdev.dev, uap);
1494 
1495 	/* We still activate the port even when failing to request resources
1496 	 * to work around bugs in ancient Apple device-trees
1497 	 */
1498 	if (macio_request_resources(uap->dev, "pmac_zilog"))
1499 		printk(KERN_WARNING "%pOFn: Failed to request resource"
1500 		       ", port still active\n",
1501 		       uap->node);
1502 	else
1503 		uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
1504 
1505 	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1506 }
1507 
1508 /*
1509  * That one should not be called, macio isn't really a hotswap device,
1510  * we don't expect one of those serial ports to go away...
1511  */
1512 static int pmz_detach(struct macio_dev *mdev)
1513 {
1514 	struct uart_pmac_port	*uap = dev_get_drvdata(&mdev->ofdev.dev);
1515 
1516 	if (!uap)
1517 		return -ENODEV;
1518 
1519 	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1520 
1521 	if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
1522 		macio_release_resources(uap->dev);
1523 		uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
1524 	}
1525 	dev_set_drvdata(&mdev->ofdev.dev, NULL);
1526 	uap->dev = NULL;
1527 	uap->port.dev = NULL;
1528 
1529 	return 0;
1530 }
1531 
1532 
1533 static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
1534 {
1535 	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1536 
1537 	if (uap == NULL) {
1538 		printk("HRM... pmz_suspend with NULL uap\n");
1539 		return 0;
1540 	}
1541 
1542 	uart_suspend_port(&pmz_uart_reg, &uap->port);
1543 
1544 	return 0;
1545 }
1546 
1547 
1548 static int pmz_resume(struct macio_dev *mdev)
1549 {
1550 	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1551 
1552 	if (uap == NULL)
1553 		return 0;
1554 
1555 	uart_resume_port(&pmz_uart_reg, &uap->port);
1556 
1557 	return 0;
1558 }
1559 
1560 /*
1561  * Probe all ports in the system and build the ports array, we register
1562  * with the serial layer later, so we get a proper struct device which
1563  * allows the tty to attach properly. This is later than it used to be
1564  * but the tty layer really wants it that way.
1565  */
1566 static int __init pmz_probe(void)
1567 {
1568 	struct device_node	*node_p, *node_a, *node_b, *np;
1569 	int			count = 0;
1570 	int			rc;
1571 
1572 	/*
1573 	 * Find all escc chips in the system
1574 	 */
1575 	for_each_node_by_name(node_p, "escc") {
1576 		/*
1577 		 * First get channel A/B node pointers
1578 		 *
1579 		 * TODO: Add routines with proper locking to do that...
1580 		 */
1581 		node_a = node_b = NULL;
1582 		for_each_child_of_node(node_p, np) {
1583 			if (of_node_name_prefix(np, "ch-a"))
1584 				node_a = of_node_get(np);
1585 			else if (of_node_name_prefix(np, "ch-b"))
1586 				node_b = of_node_get(np);
1587 		}
1588 		if (!node_a && !node_b) {
1589 			of_node_put(node_a);
1590 			of_node_put(node_b);
1591 			printk(KERN_ERR "pmac_zilog: missing node %c for escc %pOF\n",
1592 				(!node_a) ? 'a' : 'b', node_p);
1593 			continue;
1594 		}
1595 
1596 		/*
1597 		 * Fill basic fields in the port structures
1598 		 */
1599 		if (node_b != NULL) {
1600 			pmz_ports[count].mate		= &pmz_ports[count+1];
1601 			pmz_ports[count+1].mate		= &pmz_ports[count];
1602 		}
1603 		pmz_ports[count].flags		= PMACZILOG_FLAG_IS_CHANNEL_A;
1604 		pmz_ports[count].node		= node_a;
1605 		pmz_ports[count+1].node		= node_b;
1606 		pmz_ports[count].port.line	= count;
1607 		pmz_ports[count+1].port.line	= count+1;
1608 
1609 		/*
1610 		 * Setup the ports for real
1611 		 */
1612 		rc = pmz_init_port(&pmz_ports[count]);
1613 		if (rc == 0 && node_b != NULL)
1614 			rc = pmz_init_port(&pmz_ports[count+1]);
1615 		if (rc != 0) {
1616 			of_node_put(node_a);
1617 			of_node_put(node_b);
1618 			memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
1619 			memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
1620 			continue;
1621 		}
1622 		count += 2;
1623 	}
1624 	pmz_ports_count = count;
1625 
1626 	return 0;
1627 }
1628 
1629 #else
1630 
1631 /* On PCI PowerMacs, pmz_probe() does an explicit search of the OpenFirmware
1632  * tree to obtain the device_nodes needed to start the console before the
1633  * macio driver. On Macs without OpenFirmware, global platform_devices take
1634  * the place of those device_nodes.
1635  */
1636 extern struct platform_device scc_a_pdev, scc_b_pdev;
1637 
1638 static int __init pmz_init_port(struct uart_pmac_port *uap)
1639 {
1640 	struct resource *r_ports;
1641 	int irq;
1642 
1643 	r_ports = platform_get_resource(uap->pdev, IORESOURCE_MEM, 0);
1644 	if (!r_ports)
1645 		return -ENODEV;
1646 
1647 	irq = platform_get_irq(uap->pdev, 0);
1648 	if (irq < 0)
1649 		return irq;
1650 
1651 	uap->port.mapbase  = r_ports->start;
1652 	uap->port.membase  = (unsigned char __iomem *) r_ports->start;
1653 	uap->port.iotype   = UPIO_MEM;
1654 	uap->port.irq      = irq;
1655 	uap->port.uartclk  = ZS_CLOCK;
1656 	uap->port.fifosize = 1;
1657 	uap->port.ops      = &pmz_pops;
1658 	uap->port.type     = PORT_PMAC_ZILOG;
1659 	uap->port.flags    = 0;
1660 
1661 	uap->control_reg   = uap->port.membase;
1662 	uap->data_reg      = uap->control_reg + 4;
1663 	uap->port_type     = 0;
1664 	uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PMACZILOG_CONSOLE);
1665 
1666 	pmz_convert_to_zs(uap, CS8, 0, 9600);
1667 
1668 	return 0;
1669 }
1670 
1671 static int __init pmz_probe(void)
1672 {
1673 	int err;
1674 
1675 	pmz_ports_count = 0;
1676 
1677 	pmz_ports[0].port.line = 0;
1678 	pmz_ports[0].flags     = PMACZILOG_FLAG_IS_CHANNEL_A;
1679 	pmz_ports[0].pdev      = &scc_a_pdev;
1680 	err = pmz_init_port(&pmz_ports[0]);
1681 	if (err)
1682 		return err;
1683 	pmz_ports_count++;
1684 
1685 	pmz_ports[0].mate      = &pmz_ports[1];
1686 	pmz_ports[1].mate      = &pmz_ports[0];
1687 	pmz_ports[1].port.line = 1;
1688 	pmz_ports[1].flags     = 0;
1689 	pmz_ports[1].pdev      = &scc_b_pdev;
1690 	err = pmz_init_port(&pmz_ports[1]);
1691 	if (err)
1692 		return err;
1693 	pmz_ports_count++;
1694 
1695 	return 0;
1696 }
1697 
1698 static void pmz_dispose_port(struct uart_pmac_port *uap)
1699 {
1700 	memset(uap, 0, sizeof(struct uart_pmac_port));
1701 }
1702 
1703 static int __init pmz_attach(struct platform_device *pdev)
1704 {
1705 	struct uart_pmac_port *uap;
1706 	int i;
1707 
1708 	/* Iterate the pmz_ports array to find a matching entry */
1709 	for (i = 0; i < pmz_ports_count; i++)
1710 		if (pmz_ports[i].pdev == pdev)
1711 			break;
1712 	if (i >= pmz_ports_count)
1713 		return -ENODEV;
1714 
1715 	uap = &pmz_ports[i];
1716 	uap->port.dev = &pdev->dev;
1717 	platform_set_drvdata(pdev, uap);
1718 
1719 	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1720 }
1721 
1722 static int __exit pmz_detach(struct platform_device *pdev)
1723 {
1724 	struct uart_pmac_port *uap = platform_get_drvdata(pdev);
1725 
1726 	if (!uap)
1727 		return -ENODEV;
1728 
1729 	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1730 
1731 	uap->port.dev = NULL;
1732 
1733 	return 0;
1734 }
1735 
1736 #endif /* !CONFIG_PPC_PMAC */
1737 
1738 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1739 
1740 static void pmz_console_write(struct console *con, const char *s, unsigned int count);
1741 static int __init pmz_console_setup(struct console *co, char *options);
1742 
1743 static struct console pmz_console = {
1744 	.name	=	PMACZILOG_NAME,
1745 	.write	=	pmz_console_write,
1746 	.device	=	uart_console_device,
1747 	.setup	=	pmz_console_setup,
1748 	.flags	=	CON_PRINTBUFFER,
1749 	.index	=	-1,
1750 	.data   =	&pmz_uart_reg,
1751 };
1752 
1753 #define PMACZILOG_CONSOLE	&pmz_console
1754 #else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1755 #define PMACZILOG_CONSOLE	(NULL)
1756 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1757 
1758 /*
1759  * Register the driver, console driver and ports with the serial
1760  * core
1761  */
1762 static int __init pmz_register(void)
1763 {
1764 	pmz_uart_reg.nr = pmz_ports_count;
1765 	pmz_uart_reg.cons = PMACZILOG_CONSOLE;
1766 
1767 	/*
1768 	 * Register this driver with the serial core
1769 	 */
1770 	return uart_register_driver(&pmz_uart_reg);
1771 }
1772 
1773 #ifdef CONFIG_PPC_PMAC
1774 
1775 static const struct of_device_id pmz_match[] =
1776 {
1777 	{
1778 	.name		= "ch-a",
1779 	},
1780 	{
1781 	.name		= "ch-b",
1782 	},
1783 	{},
1784 };
1785 MODULE_DEVICE_TABLE (of, pmz_match);
1786 
1787 static struct macio_driver pmz_driver = {
1788 	.driver = {
1789 		.name 		= "pmac_zilog",
1790 		.owner		= THIS_MODULE,
1791 		.of_match_table	= pmz_match,
1792 	},
1793 	.probe		= pmz_attach,
1794 	.remove		= pmz_detach,
1795 	.suspend	= pmz_suspend,
1796 	.resume		= pmz_resume,
1797 };
1798 
1799 #else
1800 
1801 static struct platform_driver pmz_driver = {
1802 	.remove		= __exit_p(pmz_detach),
1803 	.driver		= {
1804 		.name		= "scc",
1805 	},
1806 };
1807 
1808 #endif /* !CONFIG_PPC_PMAC */
1809 
1810 static int __init init_pmz(void)
1811 {
1812 	int rc, i;
1813 
1814 	/*
1815 	 * First, we need to do a direct OF-based probe pass. We
1816 	 * do that because we want serial console up before the
1817 	 * macio stuffs calls us back, and since that makes it
1818 	 * easier to pass the proper number of channels to
1819 	 * uart_register_driver()
1820 	 */
1821 	if (pmz_ports_count == 0)
1822 		pmz_probe();
1823 
1824 	/*
1825 	 * Bail early if no port found
1826 	 */
1827 	if (pmz_ports_count == 0)
1828 		return -ENODEV;
1829 
1830 	/*
1831 	 * Now we register with the serial layer
1832 	 */
1833 	rc = pmz_register();
1834 	if (rc) {
1835 		printk(KERN_ERR
1836 			"pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"
1837 		 	"pmac_zilog: Did another serial driver already claim the minors?\n");
1838 		/* effectively "pmz_unprobe()" */
1839 		for (i=0; i < pmz_ports_count; i++)
1840 			pmz_dispose_port(&pmz_ports[i]);
1841 		return rc;
1842 	}
1843 
1844 	/*
1845 	 * Then we register the macio driver itself
1846 	 */
1847 #ifdef CONFIG_PPC_PMAC
1848 	return macio_register_driver(&pmz_driver);
1849 #else
1850 	return platform_driver_probe(&pmz_driver, pmz_attach);
1851 #endif
1852 }
1853 
1854 static void __exit exit_pmz(void)
1855 {
1856 	int i;
1857 
1858 #ifdef CONFIG_PPC_PMAC
1859 	/* Get rid of macio-driver (detach from macio) */
1860 	macio_unregister_driver(&pmz_driver);
1861 #else
1862 	platform_driver_unregister(&pmz_driver);
1863 #endif
1864 
1865 	for (i = 0; i < pmz_ports_count; i++) {
1866 		struct uart_pmac_port *uport = &pmz_ports[i];
1867 #ifdef CONFIG_PPC_PMAC
1868 		if (uport->node != NULL)
1869 			pmz_dispose_port(uport);
1870 #else
1871 		if (uport->pdev != NULL)
1872 			pmz_dispose_port(uport);
1873 #endif
1874 	}
1875 	/* Unregister UART driver */
1876 	uart_unregister_driver(&pmz_uart_reg);
1877 }
1878 
1879 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1880 
1881 static void pmz_console_putchar(struct uart_port *port, unsigned char ch)
1882 {
1883 	struct uart_pmac_port *uap =
1884 		container_of(port, struct uart_pmac_port, port);
1885 
1886 	/* Wait for the transmit buffer to empty. */
1887 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1888 		udelay(5);
1889 	write_zsdata(uap, ch);
1890 }
1891 
1892 /*
1893  * Print a string to the serial port trying not to disturb
1894  * any possible real use of the port...
1895  */
1896 static void pmz_console_write(struct console *con, const char *s, unsigned int count)
1897 {
1898 	struct uart_pmac_port *uap = &pmz_ports[con->index];
1899 	unsigned long flags;
1900 
1901 	spin_lock_irqsave(&uap->port.lock, flags);
1902 
1903 	/* Turn of interrupts and enable the transmitter. */
1904 	write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);
1905 	write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);
1906 
1907 	uart_console_write(&uap->port, s, count, pmz_console_putchar);
1908 
1909 	/* Restore the values in the registers. */
1910 	write_zsreg(uap, R1, uap->curregs[1]);
1911 	/* Don't disable the transmitter. */
1912 
1913 	spin_unlock_irqrestore(&uap->port.lock, flags);
1914 }
1915 
1916 /*
1917  * Setup the serial console
1918  */
1919 static int __init pmz_console_setup(struct console *co, char *options)
1920 {
1921 	struct uart_pmac_port *uap;
1922 	struct uart_port *port;
1923 	int baud = 38400;
1924 	int bits = 8;
1925 	int parity = 'n';
1926 	int flow = 'n';
1927 	unsigned long pwr_delay;
1928 
1929 	/*
1930 	 * XServe's default to 57600 bps
1931 	 */
1932 	if (of_machine_is_compatible("RackMac1,1")
1933 	    || of_machine_is_compatible("RackMac1,2")
1934 	    || of_machine_is_compatible("MacRISC4"))
1935 		baud = 57600;
1936 
1937 	/*
1938 	 * Check whether an invalid uart number has been specified, and
1939 	 * if so, search for the first available port that does have
1940 	 * console support.
1941 	 */
1942 	if (co->index >= pmz_ports_count)
1943 		co->index = 0;
1944 	uap = &pmz_ports[co->index];
1945 #ifdef CONFIG_PPC_PMAC
1946 	if (uap->node == NULL)
1947 		return -ENODEV;
1948 #else
1949 	if (uap->pdev == NULL)
1950 		return -ENODEV;
1951 #endif
1952 	port = &uap->port;
1953 
1954 	/*
1955 	 * Mark port as beeing a console
1956 	 */
1957 	uap->flags |= PMACZILOG_FLAG_IS_CONS;
1958 
1959 	/*
1960 	 * Temporary fix for uart layer who didn't setup the spinlock yet
1961 	 */
1962 	spin_lock_init(&port->lock);
1963 
1964 	/*
1965 	 * Enable the hardware
1966 	 */
1967 	pwr_delay = __pmz_startup(uap);
1968 	if (pwr_delay)
1969 		mdelay(pwr_delay);
1970 
1971 	if (options)
1972 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1973 
1974 	return uart_set_options(port, co, baud, parity, bits, flow);
1975 }
1976 
1977 static int __init pmz_console_init(void)
1978 {
1979 	/* Probe ports */
1980 	pmz_probe();
1981 
1982 	if (pmz_ports_count == 0)
1983 		return -ENODEV;
1984 
1985 	/* TODO: Autoprobe console based on OF */
1986 	/* pmz_console.index = i; */
1987 	register_console(&pmz_console);
1988 
1989 	return 0;
1990 
1991 }
1992 console_initcall(pmz_console_init);
1993 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1994 
1995 module_init(init_pmz);
1996 module_exit(exit_pmz);
1997