xref: /openbmc/linux/drivers/tty/serial/pmac_zilog.c (revision 465191d6)
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/dbdma.h>
56 #include <asm/macio.h>
57 #else
58 #include <linux/platform_device.h>
59 #define of_machine_is_compatible(x) (0)
60 #endif
61 
62 #include <linux/serial.h>
63 #include <linux/serial_core.h>
64 
65 #include "pmac_zilog.h"
66 
67 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
68 MODULE_DESCRIPTION("Driver for the Mac and PowerMac serial ports.");
69 MODULE_LICENSE("GPL");
70 
71 #ifdef CONFIG_SERIAL_PMACZILOG_TTYS
72 #define PMACZILOG_MAJOR		TTY_MAJOR
73 #define PMACZILOG_MINOR		64
74 #define PMACZILOG_NAME		"ttyS"
75 #else
76 #define PMACZILOG_MAJOR		204
77 #define PMACZILOG_MINOR		192
78 #define PMACZILOG_NAME		"ttyPZ"
79 #endif
80 
81 #define pmz_debug(fmt, arg...)	pr_debug("ttyPZ%d: " fmt, uap->port.line, ## arg)
82 #define pmz_error(fmt, arg...)	pr_err("ttyPZ%d: " fmt, uap->port.line, ## arg)
83 #define pmz_info(fmt, arg...)	pr_info("ttyPZ%d: " fmt, uap->port.line, ## arg)
84 
85 /*
86  * For the sake of early serial console, we can do a pre-probe
87  * (optional) of the ports at rather early boot time.
88  */
89 static struct uart_pmac_port	pmz_ports[MAX_ZS_PORTS];
90 static int			pmz_ports_count;
91 
92 static struct uart_driver pmz_uart_reg = {
93 	.owner		=	THIS_MODULE,
94 	.driver_name	=	PMACZILOG_NAME,
95 	.dev_name	=	PMACZILOG_NAME,
96 	.major		=	PMACZILOG_MAJOR,
97 	.minor		=	PMACZILOG_MINOR,
98 };
99 
100 
101 /*
102  * Load all registers to reprogram the port
103  * This function must only be called when the TX is not busy.  The UART
104  * port lock must be held and local interrupts disabled.
105  */
106 static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
107 {
108 	int i;
109 
110 	/* Let pending transmits finish.  */
111 	for (i = 0; i < 1000; i++) {
112 		unsigned char stat = read_zsreg(uap, R1);
113 		if (stat & ALL_SNT)
114 			break;
115 		udelay(100);
116 	}
117 
118 	ZS_CLEARERR(uap);
119 	zssync(uap);
120 	ZS_CLEARFIFO(uap);
121 	zssync(uap);
122 	ZS_CLEARERR(uap);
123 
124 	/* Disable all interrupts.  */
125 	write_zsreg(uap, R1,
126 		    regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
127 
128 	/* Set parity, sync config, stop bits, and clock divisor.  */
129 	write_zsreg(uap, R4, regs[R4]);
130 
131 	/* Set misc. TX/RX control bits.  */
132 	write_zsreg(uap, R10, regs[R10]);
133 
134 	/* Set TX/RX controls sans the enable bits.  */
135 	write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
136 	write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
137 
138 	/* now set R7 "prime" on ESCC */
139 	write_zsreg(uap, R15, regs[R15] | EN85C30);
140 	write_zsreg(uap, R7, regs[R7P]);
141 
142 	/* make sure we use R7 "non-prime" on ESCC */
143 	write_zsreg(uap, R15, regs[R15] & ~EN85C30);
144 
145 	/* Synchronous mode config.  */
146 	write_zsreg(uap, R6, regs[R6]);
147 	write_zsreg(uap, R7, regs[R7]);
148 
149 	/* Disable baud generator.  */
150 	write_zsreg(uap, R14, regs[R14] & ~BRENAB);
151 
152 	/* Clock mode control.  */
153 	write_zsreg(uap, R11, regs[R11]);
154 
155 	/* Lower and upper byte of baud rate generator divisor.  */
156 	write_zsreg(uap, R12, regs[R12]);
157 	write_zsreg(uap, R13, regs[R13]);
158 
159 	/* Now rewrite R14, with BRENAB (if set).  */
160 	write_zsreg(uap, R14, regs[R14]);
161 
162 	/* Reset external status interrupts.  */
163 	write_zsreg(uap, R0, RES_EXT_INT);
164 	write_zsreg(uap, R0, RES_EXT_INT);
165 
166 	/* Rewrite R3/R5, this time without enables masked.  */
167 	write_zsreg(uap, R3, regs[R3]);
168 	write_zsreg(uap, R5, regs[R5]);
169 
170 	/* Rewrite R1, this time without IRQ enabled masked.  */
171 	write_zsreg(uap, R1, regs[R1]);
172 
173 	/* Enable interrupts */
174 	write_zsreg(uap, R9, regs[R9]);
175 }
176 
177 /*
178  * We do like sunzilog to avoid disrupting pending Tx
179  * Reprogram the Zilog channel HW registers with the copies found in the
180  * software state struct.  If the transmitter is busy, we defer this update
181  * until the next TX complete interrupt.  Else, we do it right now.
182  *
183  * The UART port lock must be held and local interrupts disabled.
184  */
185 static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
186 {
187 	if (!ZS_REGS_HELD(uap)) {
188 		if (ZS_TX_ACTIVE(uap)) {
189 			uap->flags |= PMACZILOG_FLAG_REGS_HELD;
190 		} else {
191 			pmz_debug("pmz: maybe_update_regs: updating\n");
192 			pmz_load_zsregs(uap, uap->curregs);
193 		}
194 	}
195 }
196 
197 static void pmz_interrupt_control(struct uart_pmac_port *uap, int enable)
198 {
199 	if (enable) {
200 		uap->curregs[1] |= INT_ALL_Rx | TxINT_ENAB;
201 		if (!ZS_IS_EXTCLK(uap))
202 			uap->curregs[1] |= EXT_INT_ENAB;
203 	} else {
204 		uap->curregs[1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
205 	}
206 	write_zsreg(uap, R1, uap->curregs[1]);
207 }
208 
209 static bool pmz_receive_chars(struct uart_pmac_port *uap)
210 	__must_hold(&uap->port.lock)
211 {
212 	struct tty_port *port;
213 	unsigned char ch, r1, drop, flag;
214 	int loops = 0;
215 
216 	/* Sanity check, make sure the old bug is no longer happening */
217 	if (uap->port.state == NULL) {
218 		WARN_ON(1);
219 		(void)read_zsdata(uap);
220 		return false;
221 	}
222 	port = &uap->port.state->port;
223 
224 	while (1) {
225 		drop = 0;
226 
227 		r1 = read_zsreg(uap, R1);
228 		ch = read_zsdata(uap);
229 
230 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
231 			write_zsreg(uap, R0, ERR_RES);
232 			zssync(uap);
233 		}
234 
235 		ch &= uap->parity_mask;
236 		if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
237 			uap->flags &= ~PMACZILOG_FLAG_BREAK;
238 		}
239 
240 #if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
241 #ifdef USE_CTRL_O_SYSRQ
242 		/* Handle the SysRq ^O Hack */
243 		if (ch == '\x0f') {
244 			uap->port.sysrq = jiffies + HZ*5;
245 			goto next_char;
246 		}
247 #endif /* USE_CTRL_O_SYSRQ */
248 		if (uap->port.sysrq) {
249 			int swallow;
250 			spin_unlock(&uap->port.lock);
251 			swallow = uart_handle_sysrq_char(&uap->port, ch);
252 			spin_lock(&uap->port.lock);
253 			if (swallow)
254 				goto next_char;
255 		}
256 #endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
257 
258 		/* A real serial line, record the character and status.  */
259 		if (drop)
260 			goto next_char;
261 
262 		flag = TTY_NORMAL;
263 		uap->port.icount.rx++;
264 
265 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
266 			if (r1 & BRK_ABRT) {
267 				pmz_debug("pmz: got break !\n");
268 				r1 &= ~(PAR_ERR | CRC_ERR);
269 				uap->port.icount.brk++;
270 				if (uart_handle_break(&uap->port))
271 					goto next_char;
272 			}
273 			else if (r1 & PAR_ERR)
274 				uap->port.icount.parity++;
275 			else if (r1 & CRC_ERR)
276 				uap->port.icount.frame++;
277 			if (r1 & Rx_OVR)
278 				uap->port.icount.overrun++;
279 			r1 &= uap->port.read_status_mask;
280 			if (r1 & BRK_ABRT)
281 				flag = TTY_BREAK;
282 			else if (r1 & PAR_ERR)
283 				flag = TTY_PARITY;
284 			else if (r1 & CRC_ERR)
285 				flag = TTY_FRAME;
286 		}
287 
288 		if (uap->port.ignore_status_mask == 0xff ||
289 		    (r1 & uap->port.ignore_status_mask) == 0) {
290 			tty_insert_flip_char(port, ch, flag);
291 		}
292 		if (r1 & Rx_OVR)
293 			tty_insert_flip_char(port, 0, TTY_OVERRUN);
294 	next_char:
295 		/* We can get stuck in an infinite loop getting char 0 when the
296 		 * line is in a wrong HW state, we break that here.
297 		 * When that happens, I disable the receive side of the driver.
298 		 * Note that what I've been experiencing is a real irq loop where
299 		 * I'm getting flooded regardless of the actual port speed.
300 		 * Something strange is going on with the HW
301 		 */
302 		if ((++loops) > 1000)
303 			goto flood;
304 		ch = read_zsreg(uap, R0);
305 		if (!(ch & Rx_CH_AV))
306 			break;
307 	}
308 
309 	return true;
310  flood:
311 	pmz_interrupt_control(uap, 0);
312 	pmz_error("pmz: rx irq flood !\n");
313 	return true;
314 }
315 
316 static void pmz_status_handle(struct uart_pmac_port *uap)
317 {
318 	unsigned char status;
319 
320 	status = read_zsreg(uap, R0);
321 	write_zsreg(uap, R0, RES_EXT_INT);
322 	zssync(uap);
323 
324 	if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
325 		if (status & SYNC_HUNT)
326 			uap->port.icount.dsr++;
327 
328 		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
329 		 * But it does not tell us which bit has changed, we have to keep
330 		 * track of this ourselves.
331 		 * The CTS input is inverted for some reason.  -- paulus
332 		 */
333 		if ((status ^ uap->prev_status) & DCD)
334 			uart_handle_dcd_change(&uap->port,
335 					       (status & DCD));
336 		if ((status ^ uap->prev_status) & CTS)
337 			uart_handle_cts_change(&uap->port,
338 					       !(status & CTS));
339 
340 		wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
341 	}
342 
343 	if (status & BRK_ABRT)
344 		uap->flags |= PMACZILOG_FLAG_BREAK;
345 
346 	uap->prev_status = status;
347 }
348 
349 static void pmz_transmit_chars(struct uart_pmac_port *uap)
350 {
351 	struct circ_buf *xmit;
352 
353 	if (ZS_IS_CONS(uap)) {
354 		unsigned char status = read_zsreg(uap, R0);
355 
356 		/* TX still busy?  Just wait for the next TX done interrupt.
357 		 *
358 		 * It can occur because of how we do serial console writes.  It would
359 		 * be nice to transmit console writes just like we normally would for
360 		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not
361 		 * easy because console writes cannot sleep.  One solution might be
362 		 * to poll on enough port->xmit space becoming free.  -DaveM
363 		 */
364 		if (!(status & Tx_BUF_EMP))
365 			return;
366 	}
367 
368 	uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
369 
370 	if (ZS_REGS_HELD(uap)) {
371 		pmz_load_zsregs(uap, uap->curregs);
372 		uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
373 	}
374 
375 	if (ZS_TX_STOPPED(uap)) {
376 		uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
377 		goto ack_tx_int;
378 	}
379 
380 	/* Under some circumstances, we see interrupts reported for
381 	 * a closed channel. The interrupt mask in R1 is clear, but
382 	 * R3 still signals the interrupts and we see them when taking
383 	 * an interrupt for the other channel (this could be a qemu
384 	 * bug but since the ESCC doc doesn't specify precsiely whether
385 	 * R3 interrup status bits are masked by R1 interrupt enable
386 	 * bits, better safe than sorry). --BenH.
387 	 */
388 	if (!ZS_IS_OPEN(uap))
389 		goto ack_tx_int;
390 
391 	if (uap->port.x_char) {
392 		uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
393 		write_zsdata(uap, uap->port.x_char);
394 		zssync(uap);
395 		uap->port.icount.tx++;
396 		uap->port.x_char = 0;
397 		return;
398 	}
399 
400 	if (uap->port.state == NULL)
401 		goto ack_tx_int;
402 	xmit = &uap->port.state->xmit;
403 	if (uart_circ_empty(xmit)) {
404 		uart_write_wakeup(&uap->port);
405 		goto ack_tx_int;
406 	}
407 	if (uart_tx_stopped(&uap->port))
408 		goto ack_tx_int;
409 
410 	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
411 	write_zsdata(uap, xmit->buf[xmit->tail]);
412 	zssync(uap);
413 
414 	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
415 	uap->port.icount.tx++;
416 
417 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
418 		uart_write_wakeup(&uap->port);
419 
420 	return;
421 
422 ack_tx_int:
423 	write_zsreg(uap, R0, RES_Tx_P);
424 	zssync(uap);
425 }
426 
427 /* Hrm... we register that twice, fixme later.... */
428 static irqreturn_t pmz_interrupt(int irq, void *dev_id)
429 {
430 	struct uart_pmac_port *uap = dev_id;
431 	struct uart_pmac_port *uap_a;
432 	struct uart_pmac_port *uap_b;
433 	int rc = IRQ_NONE;
434 	bool push;
435 	u8 r3;
436 
437 	uap_a = pmz_get_port_A(uap);
438 	uap_b = uap_a->mate;
439 
440 	spin_lock(&uap_a->port.lock);
441 	r3 = read_zsreg(uap_a, R3);
442 
443 	/* Channel A */
444 	push = false;
445 	if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
446 		if (!ZS_IS_OPEN(uap_a)) {
447 			pmz_debug("ChanA interrupt while not open !\n");
448 			goto skip_a;
449 		}
450 		write_zsreg(uap_a, R0, RES_H_IUS);
451 		zssync(uap_a);
452 		if (r3 & CHAEXT)
453 			pmz_status_handle(uap_a);
454 		if (r3 & CHARxIP)
455 			push = pmz_receive_chars(uap_a);
456 		if (r3 & CHATxIP)
457 			pmz_transmit_chars(uap_a);
458 		rc = IRQ_HANDLED;
459 	}
460  skip_a:
461 	spin_unlock(&uap_a->port.lock);
462 	if (push)
463 		tty_flip_buffer_push(&uap->port.state->port);
464 
465 	if (!uap_b)
466 		goto out;
467 
468 	spin_lock(&uap_b->port.lock);
469 	push = false;
470 	if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
471 		if (!ZS_IS_OPEN(uap_b)) {
472 			pmz_debug("ChanB interrupt while not open !\n");
473 			goto skip_b;
474 		}
475 		write_zsreg(uap_b, R0, RES_H_IUS);
476 		zssync(uap_b);
477 		if (r3 & CHBEXT)
478 			pmz_status_handle(uap_b);
479 		if (r3 & CHBRxIP)
480 			push = pmz_receive_chars(uap_b);
481 		if (r3 & CHBTxIP)
482 			pmz_transmit_chars(uap_b);
483 		rc = IRQ_HANDLED;
484 	}
485  skip_b:
486 	spin_unlock(&uap_b->port.lock);
487 	if (push)
488 		tty_flip_buffer_push(&uap->port.state->port);
489 
490  out:
491 	return rc;
492 }
493 
494 /*
495  * Peek the status register, lock not held by caller
496  */
497 static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
498 {
499 	unsigned long flags;
500 	u8 status;
501 
502 	spin_lock_irqsave(&uap->port.lock, flags);
503 	status = read_zsreg(uap, R0);
504 	spin_unlock_irqrestore(&uap->port.lock, flags);
505 
506 	return status;
507 }
508 
509 /*
510  * Check if transmitter is empty
511  * The port lock is not held.
512  */
513 static unsigned int pmz_tx_empty(struct uart_port *port)
514 {
515 	unsigned char status;
516 
517 	status = pmz_peek_status(to_pmz(port));
518 	if (status & Tx_BUF_EMP)
519 		return TIOCSER_TEMT;
520 	return 0;
521 }
522 
523 /*
524  * Set Modem Control (RTS & DTR) bits
525  * The port lock is held and interrupts are disabled.
526  * Note: Shall we really filter out RTS on external ports or
527  * should that be dealt at higher level only ?
528  */
529 static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
530 {
531 	struct uart_pmac_port *uap = to_pmz(port);
532 	unsigned char set_bits, clear_bits;
533 
534         /* Do nothing for irda for now... */
535 	if (ZS_IS_IRDA(uap))
536 		return;
537 	/* We get called during boot with a port not up yet */
538 	if (!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
539 		return;
540 
541 	set_bits = clear_bits = 0;
542 
543 	if (ZS_IS_INTMODEM(uap)) {
544 		if (mctrl & TIOCM_RTS)
545 			set_bits |= RTS;
546 		else
547 			clear_bits |= RTS;
548 	}
549 	if (mctrl & TIOCM_DTR)
550 		set_bits |= DTR;
551 	else
552 		clear_bits |= DTR;
553 
554 	/* NOTE: Not subject to 'transmitter active' rule.  */
555 	uap->curregs[R5] |= set_bits;
556 	uap->curregs[R5] &= ~clear_bits;
557 
558 	write_zsreg(uap, R5, uap->curregs[R5]);
559 	pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
560 		  set_bits, clear_bits, uap->curregs[R5]);
561 	zssync(uap);
562 }
563 
564 /*
565  * Get Modem Control bits (only the input ones, the core will
566  * or that with a cached value of the control ones)
567  * The port lock is held and interrupts are disabled.
568  */
569 static unsigned int pmz_get_mctrl(struct uart_port *port)
570 {
571 	struct uart_pmac_port *uap = to_pmz(port);
572 	unsigned char status;
573 	unsigned int ret;
574 
575 	status = read_zsreg(uap, R0);
576 
577 	ret = 0;
578 	if (status & DCD)
579 		ret |= TIOCM_CAR;
580 	if (status & SYNC_HUNT)
581 		ret |= TIOCM_DSR;
582 	if (!(status & CTS))
583 		ret |= TIOCM_CTS;
584 
585 	return ret;
586 }
587 
588 /*
589  * Stop TX side. Dealt like sunzilog at next Tx interrupt,
590  * though for DMA, we will have to do a bit more.
591  * The port lock is held and interrupts are disabled.
592  */
593 static void pmz_stop_tx(struct uart_port *port)
594 {
595 	to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
596 }
597 
598 /*
599  * Kick the Tx side.
600  * The port lock is held and interrupts are disabled.
601  */
602 static void pmz_start_tx(struct uart_port *port)
603 {
604 	struct uart_pmac_port *uap = to_pmz(port);
605 	unsigned char status;
606 
607 	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
608 	uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
609 
610 	status = read_zsreg(uap, R0);
611 
612 	/* TX busy?  Just wait for the TX done interrupt.  */
613 	if (!(status & Tx_BUF_EMP))
614 		return;
615 
616 	/* Send the first character to jump-start the TX done
617 	 * IRQ sending engine.
618 	 */
619 	if (port->x_char) {
620 		write_zsdata(uap, port->x_char);
621 		zssync(uap);
622 		port->icount.tx++;
623 		port->x_char = 0;
624 	} else {
625 		struct circ_buf *xmit = &port->state->xmit;
626 
627 		if (uart_circ_empty(xmit))
628 			return;
629 		write_zsdata(uap, xmit->buf[xmit->tail]);
630 		zssync(uap);
631 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
632 		port->icount.tx++;
633 
634 		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
635 			uart_write_wakeup(&uap->port);
636 	}
637 }
638 
639 /*
640  * Stop Rx side, basically disable emitting of
641  * Rx interrupts on the port. We don't disable the rx
642  * side of the chip proper though
643  * The port lock is held.
644  */
645 static void pmz_stop_rx(struct uart_port *port)
646 {
647 	struct uart_pmac_port *uap = to_pmz(port);
648 
649 	/* Disable all RX interrupts.  */
650 	uap->curregs[R1] &= ~RxINT_MASK;
651 	pmz_maybe_update_regs(uap);
652 }
653 
654 /*
655  * Enable modem status change interrupts
656  * The port lock is held.
657  */
658 static void pmz_enable_ms(struct uart_port *port)
659 {
660 	struct uart_pmac_port *uap = to_pmz(port);
661 	unsigned char new_reg;
662 
663 	if (ZS_IS_IRDA(uap))
664 		return;
665 	new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
666 	if (new_reg != uap->curregs[R15]) {
667 		uap->curregs[R15] = new_reg;
668 
669 		/* NOTE: Not subject to 'transmitter active' rule. */
670 		write_zsreg(uap, R15, uap->curregs[R15]);
671 	}
672 }
673 
674 /*
675  * Control break state emission
676  * The port lock is not held.
677  */
678 static void pmz_break_ctl(struct uart_port *port, int break_state)
679 {
680 	struct uart_pmac_port *uap = to_pmz(port);
681 	unsigned char set_bits, clear_bits, new_reg;
682 	unsigned long flags;
683 
684 	set_bits = clear_bits = 0;
685 
686 	if (break_state)
687 		set_bits |= SND_BRK;
688 	else
689 		clear_bits |= SND_BRK;
690 
691 	spin_lock_irqsave(&port->lock, flags);
692 
693 	new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
694 	if (new_reg != uap->curregs[R5]) {
695 		uap->curregs[R5] = new_reg;
696 		write_zsreg(uap, R5, uap->curregs[R5]);
697 	}
698 
699 	spin_unlock_irqrestore(&port->lock, flags);
700 }
701 
702 #ifdef CONFIG_PPC_PMAC
703 
704 /*
705  * Turn power on or off to the SCC and associated stuff
706  * (port drivers, modem, IR port, etc.)
707  * Returns the number of milliseconds we should wait before
708  * trying to use the port.
709  */
710 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
711 {
712 	int delay = 0;
713 	int rc;
714 
715 	if (state) {
716 		rc = pmac_call_feature(
717 			PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
718 		pmz_debug("port power on result: %d\n", rc);
719 		if (ZS_IS_INTMODEM(uap)) {
720 			rc = pmac_call_feature(
721 				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
722 			delay = 2500;	/* wait for 2.5s before using */
723 			pmz_debug("modem power result: %d\n", rc);
724 		}
725 	} else {
726 		/* TODO: Make that depend on a timer, don't power down
727 		 * immediately
728 		 */
729 		if (ZS_IS_INTMODEM(uap)) {
730 			rc = pmac_call_feature(
731 				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
732 			pmz_debug("port power off result: %d\n", rc);
733 		}
734 		pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
735 	}
736 	return delay;
737 }
738 
739 #else
740 
741 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
742 {
743 	return 0;
744 }
745 
746 #endif /* !CONFIG_PPC_PMAC */
747 
748 /*
749  * FixZeroBug....Works around a bug in the SCC receiving channel.
750  * Inspired from Darwin code, 15 Sept. 2000  -DanM
751  *
752  * The following sequence prevents a problem that is seen with O'Hare ASICs
753  * (most versions -- also with some Heathrow and Hydra ASICs) where a zero
754  * at the input to the receiver becomes 'stuck' and locks up the receiver.
755  * This problem can occur as a result of a zero bit at the receiver input
756  * coincident with any of the following events:
757  *
758  *	The SCC is initialized (hardware or software).
759  *	A framing error is detected.
760  *	The clocking option changes from synchronous or X1 asynchronous
761  *		clocking to X16, X32, or X64 asynchronous clocking.
762  *	The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
763  *
764  * This workaround attempts to recover from the lockup condition by placing
765  * the SCC in synchronous loopback mode with a fast clock before programming
766  * any of the asynchronous modes.
767  */
768 static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
769 {
770 	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
771 	zssync(uap);
772 	udelay(10);
773 	write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
774 	zssync(uap);
775 
776 	write_zsreg(uap, 4, X1CLK | MONSYNC);
777 	write_zsreg(uap, 3, Rx8);
778 	write_zsreg(uap, 5, Tx8 | RTS);
779 	write_zsreg(uap, 9, NV);	/* Didn't we already do this? */
780 	write_zsreg(uap, 11, RCBR | TCBR);
781 	write_zsreg(uap, 12, 0);
782 	write_zsreg(uap, 13, 0);
783 	write_zsreg(uap, 14, (LOOPBAK | BRSRC));
784 	write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
785 	write_zsreg(uap, 3, Rx8 | RxENABLE);
786 	write_zsreg(uap, 0, RES_EXT_INT);
787 	write_zsreg(uap, 0, RES_EXT_INT);
788 	write_zsreg(uap, 0, RES_EXT_INT);	/* to kill some time */
789 
790 	/* The channel should be OK now, but it is probably receiving
791 	 * loopback garbage.
792 	 * Switch to asynchronous mode, disable the receiver,
793 	 * and discard everything in the receive buffer.
794 	 */
795 	write_zsreg(uap, 9, NV);
796 	write_zsreg(uap, 4, X16CLK | SB_MASK);
797 	write_zsreg(uap, 3, Rx8);
798 
799 	while (read_zsreg(uap, 0) & Rx_CH_AV) {
800 		(void)read_zsreg(uap, 8);
801 		write_zsreg(uap, 0, RES_EXT_INT);
802 		write_zsreg(uap, 0, ERR_RES);
803 	}
804 }
805 
806 /*
807  * Real startup routine, powers up the hardware and sets up
808  * the SCC. Returns a delay in ms where you need to wait before
809  * actually using the port, this is typically the internal modem
810  * powerup delay. This routine expect the lock to be taken.
811  */
812 static int __pmz_startup(struct uart_pmac_port *uap)
813 {
814 	int pwr_delay = 0;
815 
816 	memset(&uap->curregs, 0, sizeof(uap->curregs));
817 
818 	/* Power up the SCC & underlying hardware (modem/irda) */
819 	pwr_delay = pmz_set_scc_power(uap, 1);
820 
821 	/* Nice buggy HW ... */
822 	pmz_fix_zero_bug_scc(uap);
823 
824 	/* Reset the channel */
825 	uap->curregs[R9] = 0;
826 	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
827 	zssync(uap);
828 	udelay(10);
829 	write_zsreg(uap, 9, 0);
830 	zssync(uap);
831 
832 	/* Clear the interrupt registers */
833 	write_zsreg(uap, R1, 0);
834 	write_zsreg(uap, R0, ERR_RES);
835 	write_zsreg(uap, R0, ERR_RES);
836 	write_zsreg(uap, R0, RES_H_IUS);
837 	write_zsreg(uap, R0, RES_H_IUS);
838 
839 	/* Setup some valid baud rate */
840 	uap->curregs[R4] = X16CLK | SB1;
841 	uap->curregs[R3] = Rx8;
842 	uap->curregs[R5] = Tx8 | RTS;
843 	if (!ZS_IS_IRDA(uap))
844 		uap->curregs[R5] |= DTR;
845 	uap->curregs[R12] = 0;
846 	uap->curregs[R13] = 0;
847 	uap->curregs[R14] = BRENAB;
848 
849 	/* Clear handshaking, enable BREAK interrupts */
850 	uap->curregs[R15] = BRKIE;
851 
852 	/* Master interrupt enable */
853 	uap->curregs[R9] |= NV | MIE;
854 
855 	pmz_load_zsregs(uap, uap->curregs);
856 
857 	/* Enable receiver and transmitter.  */
858 	write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
859 	write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
860 
861 	/* Remember status for DCD/CTS changes */
862 	uap->prev_status = read_zsreg(uap, R0);
863 
864 	return pwr_delay;
865 }
866 
867 static void pmz_irda_reset(struct uart_pmac_port *uap)
868 {
869 	unsigned long flags;
870 
871 	spin_lock_irqsave(&uap->port.lock, flags);
872 	uap->curregs[R5] |= DTR;
873 	write_zsreg(uap, R5, uap->curregs[R5]);
874 	zssync(uap);
875 	spin_unlock_irqrestore(&uap->port.lock, flags);
876 	msleep(110);
877 
878 	spin_lock_irqsave(&uap->port.lock, flags);
879 	uap->curregs[R5] &= ~DTR;
880 	write_zsreg(uap, R5, uap->curregs[R5]);
881 	zssync(uap);
882 	spin_unlock_irqrestore(&uap->port.lock, flags);
883 	msleep(10);
884 }
885 
886 /*
887  * This is the "normal" startup routine, using the above one
888  * wrapped with the lock and doing a schedule delay
889  */
890 static int pmz_startup(struct uart_port *port)
891 {
892 	struct uart_pmac_port *uap = to_pmz(port);
893 	unsigned long flags;
894 	int pwr_delay = 0;
895 
896 	uap->flags |= PMACZILOG_FLAG_IS_OPEN;
897 
898 	/* A console is never powered down. Else, power up and
899 	 * initialize the chip
900 	 */
901 	if (!ZS_IS_CONS(uap)) {
902 		spin_lock_irqsave(&port->lock, flags);
903 		pwr_delay = __pmz_startup(uap);
904 		spin_unlock_irqrestore(&port->lock, flags);
905 	}
906 	sprintf(uap->irq_name, PMACZILOG_NAME"%d", uap->port.line);
907 	if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,
908 			uap->irq_name, uap)) {
909 		pmz_error("Unable to register zs interrupt handler.\n");
910 		pmz_set_scc_power(uap, 0);
911 		return -ENXIO;
912 	}
913 
914 	/* Right now, we deal with delay by blocking here, I'll be
915 	 * smarter later on
916 	 */
917 	if (pwr_delay != 0) {
918 		pmz_debug("pmz: delaying %d ms\n", pwr_delay);
919 		msleep(pwr_delay);
920 	}
921 
922 	/* IrDA reset is done now */
923 	if (ZS_IS_IRDA(uap))
924 		pmz_irda_reset(uap);
925 
926 	/* Enable interrupt requests for the channel */
927 	spin_lock_irqsave(&port->lock, flags);
928 	pmz_interrupt_control(uap, 1);
929 	spin_unlock_irqrestore(&port->lock, flags);
930 
931 	return 0;
932 }
933 
934 static void pmz_shutdown(struct uart_port *port)
935 {
936 	struct uart_pmac_port *uap = to_pmz(port);
937 	unsigned long flags;
938 
939 	spin_lock_irqsave(&port->lock, flags);
940 
941 	/* Disable interrupt requests for the channel */
942 	pmz_interrupt_control(uap, 0);
943 
944 	if (!ZS_IS_CONS(uap)) {
945 		/* Disable receiver and transmitter */
946 		uap->curregs[R3] &= ~RxENABLE;
947 		uap->curregs[R5] &= ~TxENABLE;
948 
949 		/* Disable break assertion */
950 		uap->curregs[R5] &= ~SND_BRK;
951 		pmz_maybe_update_regs(uap);
952 	}
953 
954 	spin_unlock_irqrestore(&port->lock, flags);
955 
956 	/* Release interrupt handler */
957 	free_irq(uap->port.irq, uap);
958 
959 	spin_lock_irqsave(&port->lock, flags);
960 
961 	uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
962 
963 	if (!ZS_IS_CONS(uap))
964 		pmz_set_scc_power(uap, 0);	/* Shut the chip down */
965 
966 	spin_unlock_irqrestore(&port->lock, flags);
967 }
968 
969 /* Shared by TTY driver and serial console setup.  The port lock is held
970  * and local interrupts are disabled.
971  */
972 static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
973 			      unsigned int iflag, unsigned long baud)
974 {
975 	int brg;
976 
977 	/* Switch to external clocking for IrDA high clock rates. That
978 	 * code could be re-used for Midi interfaces with different
979 	 * multipliers
980 	 */
981 	if (baud >= 115200 && ZS_IS_IRDA(uap)) {
982 		uap->curregs[R4] = X1CLK;
983 		uap->curregs[R11] = RCTRxCP | TCTRxCP;
984 		uap->curregs[R14] = 0; /* BRG off */
985 		uap->curregs[R12] = 0;
986 		uap->curregs[R13] = 0;
987 		uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
988 	} else {
989 		switch (baud) {
990 		case ZS_CLOCK/16:	/* 230400 */
991 			uap->curregs[R4] = X16CLK;
992 			uap->curregs[R11] = 0;
993 			uap->curregs[R14] = 0;
994 			break;
995 		case ZS_CLOCK/32:	/* 115200 */
996 			uap->curregs[R4] = X32CLK;
997 			uap->curregs[R11] = 0;
998 			uap->curregs[R14] = 0;
999 			break;
1000 		default:
1001 			uap->curregs[R4] = X16CLK;
1002 			uap->curregs[R11] = TCBR | RCBR;
1003 			brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
1004 			uap->curregs[R12] = (brg & 255);
1005 			uap->curregs[R13] = ((brg >> 8) & 255);
1006 			uap->curregs[R14] = BRENAB;
1007 		}
1008 		uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
1009 	}
1010 
1011 	/* Character size, stop bits, and parity. */
1012 	uap->curregs[3] &= ~RxN_MASK;
1013 	uap->curregs[5] &= ~TxN_MASK;
1014 
1015 	switch (cflag & CSIZE) {
1016 	case CS5:
1017 		uap->curregs[3] |= Rx5;
1018 		uap->curregs[5] |= Tx5;
1019 		uap->parity_mask = 0x1f;
1020 		break;
1021 	case CS6:
1022 		uap->curregs[3] |= Rx6;
1023 		uap->curregs[5] |= Tx6;
1024 		uap->parity_mask = 0x3f;
1025 		break;
1026 	case CS7:
1027 		uap->curregs[3] |= Rx7;
1028 		uap->curregs[5] |= Tx7;
1029 		uap->parity_mask = 0x7f;
1030 		break;
1031 	case CS8:
1032 	default:
1033 		uap->curregs[3] |= Rx8;
1034 		uap->curregs[5] |= Tx8;
1035 		uap->parity_mask = 0xff;
1036 		break;
1037 	}
1038 	uap->curregs[4] &= ~(SB_MASK);
1039 	if (cflag & CSTOPB)
1040 		uap->curregs[4] |= SB2;
1041 	else
1042 		uap->curregs[4] |= SB1;
1043 	if (cflag & PARENB)
1044 		uap->curregs[4] |= PAR_ENAB;
1045 	else
1046 		uap->curregs[4] &= ~PAR_ENAB;
1047 	if (!(cflag & PARODD))
1048 		uap->curregs[4] |= PAR_EVEN;
1049 	else
1050 		uap->curregs[4] &= ~PAR_EVEN;
1051 
1052 	uap->port.read_status_mask = Rx_OVR;
1053 	if (iflag & INPCK)
1054 		uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
1055 	if (iflag & (IGNBRK | BRKINT | PARMRK))
1056 		uap->port.read_status_mask |= BRK_ABRT;
1057 
1058 	uap->port.ignore_status_mask = 0;
1059 	if (iflag & IGNPAR)
1060 		uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
1061 	if (iflag & IGNBRK) {
1062 		uap->port.ignore_status_mask |= BRK_ABRT;
1063 		if (iflag & IGNPAR)
1064 			uap->port.ignore_status_mask |= Rx_OVR;
1065 	}
1066 
1067 	if ((cflag & CREAD) == 0)
1068 		uap->port.ignore_status_mask = 0xff;
1069 }
1070 
1071 
1072 /*
1073  * Set the irda codec on the imac to the specified baud rate.
1074  */
1075 static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
1076 {
1077 	u8 cmdbyte;
1078 	int t, version;
1079 
1080 	switch (*baud) {
1081 	/* SIR modes */
1082 	case 2400:
1083 		cmdbyte = 0x53;
1084 		break;
1085 	case 4800:
1086 		cmdbyte = 0x52;
1087 		break;
1088 	case 9600:
1089 		cmdbyte = 0x51;
1090 		break;
1091 	case 19200:
1092 		cmdbyte = 0x50;
1093 		break;
1094 	case 38400:
1095 		cmdbyte = 0x4f;
1096 		break;
1097 	case 57600:
1098 		cmdbyte = 0x4e;
1099 		break;
1100 	case 115200:
1101 		cmdbyte = 0x4d;
1102 		break;
1103 	/* The FIR modes aren't really supported at this point, how
1104 	 * do we select the speed ? via the FCR on KeyLargo ?
1105 	 */
1106 	case 1152000:
1107 		cmdbyte = 0;
1108 		break;
1109 	case 4000000:
1110 		cmdbyte = 0;
1111 		break;
1112 	default: /* 9600 */
1113 		cmdbyte = 0x51;
1114 		*baud = 9600;
1115 		break;
1116 	}
1117 
1118 	/* Wait for transmitter to drain */
1119 	t = 10000;
1120 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
1121 	       || (read_zsreg(uap, R1) & ALL_SNT) == 0) {
1122 		if (--t <= 0) {
1123 			pmz_error("transmitter didn't drain\n");
1124 			return;
1125 		}
1126 		udelay(10);
1127 	}
1128 
1129 	/* Drain the receiver too */
1130 	t = 100;
1131 	(void)read_zsdata(uap);
1132 	(void)read_zsdata(uap);
1133 	(void)read_zsdata(uap);
1134 	mdelay(10);
1135 	while (read_zsreg(uap, R0) & Rx_CH_AV) {
1136 		read_zsdata(uap);
1137 		mdelay(10);
1138 		if (--t <= 0) {
1139 			pmz_error("receiver didn't drain\n");
1140 			return;
1141 		}
1142 	}
1143 
1144 	/* Switch to command mode */
1145 	uap->curregs[R5] |= DTR;
1146 	write_zsreg(uap, R5, uap->curregs[R5]);
1147 	zssync(uap);
1148 	mdelay(1);
1149 
1150 	/* Switch SCC to 19200 */
1151 	pmz_convert_to_zs(uap, CS8, 0, 19200);
1152 	pmz_load_zsregs(uap, uap->curregs);
1153 	mdelay(1);
1154 
1155 	/* Write get_version command byte */
1156 	write_zsdata(uap, 1);
1157 	t = 5000;
1158 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1159 		if (--t <= 0) {
1160 			pmz_error("irda_setup timed out on get_version byte\n");
1161 			goto out;
1162 		}
1163 		udelay(10);
1164 	}
1165 	version = read_zsdata(uap);
1166 
1167 	if (version < 4) {
1168 		pmz_info("IrDA: dongle version %d not supported\n", version);
1169 		goto out;
1170 	}
1171 
1172 	/* Send speed mode */
1173 	write_zsdata(uap, cmdbyte);
1174 	t = 5000;
1175 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1176 		if (--t <= 0) {
1177 			pmz_error("irda_setup timed out on speed mode byte\n");
1178 			goto out;
1179 		}
1180 		udelay(10);
1181 	}
1182 	t = read_zsdata(uap);
1183 	if (t != cmdbyte)
1184 		pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
1185 
1186 	pmz_info("IrDA setup for %ld bps, dongle version: %d\n",
1187 		 *baud, version);
1188 
1189 	(void)read_zsdata(uap);
1190 	(void)read_zsdata(uap);
1191 	(void)read_zsdata(uap);
1192 
1193  out:
1194 	/* Switch back to data mode */
1195 	uap->curregs[R5] &= ~DTR;
1196 	write_zsreg(uap, R5, uap->curregs[R5]);
1197 	zssync(uap);
1198 
1199 	(void)read_zsdata(uap);
1200 	(void)read_zsdata(uap);
1201 	(void)read_zsdata(uap);
1202 }
1203 
1204 
1205 static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1206 			      struct ktermios *old)
1207 {
1208 	struct uart_pmac_port *uap = to_pmz(port);
1209 	unsigned long baud;
1210 
1211 	/* XXX Check which revs of machines actually allow 1 and 4Mb speeds
1212 	 * on the IR dongle. Note that the IRTTY driver currently doesn't know
1213 	 * about the FIR mode and high speed modes. So these are unused. For
1214 	 * implementing proper support for these, we should probably add some
1215 	 * DMA as well, at least on the Rx side, which isn't a simple thing
1216 	 * at this point.
1217 	 */
1218 	if (ZS_IS_IRDA(uap)) {
1219 		/* Calc baud rate */
1220 		baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
1221 		pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
1222 		/* Cet the irda codec to the right rate */
1223 		pmz_irda_setup(uap, &baud);
1224 		/* Set final baud rate */
1225 		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1226 		pmz_load_zsregs(uap, uap->curregs);
1227 		zssync(uap);
1228 	} else {
1229 		baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
1230 		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1231 		/* Make sure modem status interrupts are correctly configured */
1232 		if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
1233 			uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
1234 			uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
1235 		} else {
1236 			uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
1237 			uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
1238 		}
1239 
1240 		/* Load registers to the chip */
1241 		pmz_maybe_update_regs(uap);
1242 	}
1243 	uart_update_timeout(port, termios->c_cflag, baud);
1244 }
1245 
1246 /* The port lock is not held.  */
1247 static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1248 			    struct ktermios *old)
1249 {
1250 	struct uart_pmac_port *uap = to_pmz(port);
1251 	unsigned long flags;
1252 
1253 	spin_lock_irqsave(&port->lock, flags);
1254 
1255 	/* Disable IRQs on the port */
1256 	pmz_interrupt_control(uap, 0);
1257 
1258 	/* Setup new port configuration */
1259 	__pmz_set_termios(port, termios, old);
1260 
1261 	/* Re-enable IRQs on the port */
1262 	if (ZS_IS_OPEN(uap))
1263 		pmz_interrupt_control(uap, 1);
1264 
1265 	spin_unlock_irqrestore(&port->lock, flags);
1266 }
1267 
1268 static const char *pmz_type(struct uart_port *port)
1269 {
1270 	struct uart_pmac_port *uap = to_pmz(port);
1271 
1272 	if (ZS_IS_IRDA(uap))
1273 		return "Z85c30 ESCC - Infrared port";
1274 	else if (ZS_IS_INTMODEM(uap))
1275 		return "Z85c30 ESCC - Internal modem";
1276 	return "Z85c30 ESCC - Serial port";
1277 }
1278 
1279 /* We do not request/release mappings of the registers here, this
1280  * happens at early serial probe time.
1281  */
1282 static void pmz_release_port(struct uart_port *port)
1283 {
1284 }
1285 
1286 static int pmz_request_port(struct uart_port *port)
1287 {
1288 	return 0;
1289 }
1290 
1291 /* These do not need to do anything interesting either.  */
1292 static void pmz_config_port(struct uart_port *port, int flags)
1293 {
1294 }
1295 
1296 /* We do not support letting the user mess with the divisor, IRQ, etc. */
1297 static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
1298 {
1299 	return -EINVAL;
1300 }
1301 
1302 #ifdef CONFIG_CONSOLE_POLL
1303 
1304 static int pmz_poll_get_char(struct uart_port *port)
1305 {
1306 	struct uart_pmac_port *uap =
1307 		container_of(port, struct uart_pmac_port, port);
1308 	int tries = 2;
1309 
1310 	while (tries) {
1311 		if ((read_zsreg(uap, R0) & Rx_CH_AV) != 0)
1312 			return read_zsdata(uap);
1313 		if (tries--)
1314 			udelay(5);
1315 	}
1316 
1317 	return NO_POLL_CHAR;
1318 }
1319 
1320 static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
1321 {
1322 	struct uart_pmac_port *uap =
1323 		container_of(port, struct uart_pmac_port, port);
1324 
1325 	/* Wait for the transmit buffer to empty. */
1326 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1327 		udelay(5);
1328 	write_zsdata(uap, c);
1329 }
1330 
1331 #endif /* CONFIG_CONSOLE_POLL */
1332 
1333 static const struct uart_ops pmz_pops = {
1334 	.tx_empty	=	pmz_tx_empty,
1335 	.set_mctrl	=	pmz_set_mctrl,
1336 	.get_mctrl	=	pmz_get_mctrl,
1337 	.stop_tx	=	pmz_stop_tx,
1338 	.start_tx	=	pmz_start_tx,
1339 	.stop_rx	=	pmz_stop_rx,
1340 	.enable_ms	=	pmz_enable_ms,
1341 	.break_ctl	=	pmz_break_ctl,
1342 	.startup	=	pmz_startup,
1343 	.shutdown	=	pmz_shutdown,
1344 	.set_termios	=	pmz_set_termios,
1345 	.type		=	pmz_type,
1346 	.release_port	=	pmz_release_port,
1347 	.request_port	=	pmz_request_port,
1348 	.config_port	=	pmz_config_port,
1349 	.verify_port	=	pmz_verify_port,
1350 #ifdef CONFIG_CONSOLE_POLL
1351 	.poll_get_char	=	pmz_poll_get_char,
1352 	.poll_put_char	=	pmz_poll_put_char,
1353 #endif
1354 };
1355 
1356 #ifdef CONFIG_PPC_PMAC
1357 
1358 /*
1359  * Setup one port structure after probing, HW is down at this point,
1360  * Unlike sunzilog, we don't need to pre-init the spinlock as we don't
1361  * register our console before uart_add_one_port() is called
1362  */
1363 static int __init pmz_init_port(struct uart_pmac_port *uap)
1364 {
1365 	struct device_node *np = uap->node;
1366 	const char *conn;
1367 	const struct slot_names_prop {
1368 		int	count;
1369 		char	name[1];
1370 	} *slots;
1371 	int len;
1372 	struct resource r_ports;
1373 
1374 	/*
1375 	 * Request & map chip registers
1376 	 */
1377 	if (of_address_to_resource(np, 0, &r_ports))
1378 		return -ENODEV;
1379 	uap->port.mapbase = r_ports.start;
1380 	uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
1381 
1382 	uap->control_reg = uap->port.membase;
1383 	uap->data_reg = uap->control_reg + 0x10;
1384 
1385 	/*
1386 	 * Detect port type
1387 	 */
1388 	if (of_device_is_compatible(np, "cobalt"))
1389 		uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1390 	conn = of_get_property(np, "AAPL,connector", &len);
1391 	if (conn && (strcmp(conn, "infrared") == 0))
1392 		uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1393 	uap->port_type = PMAC_SCC_ASYNC;
1394 	/* 1999 Powerbook G3 has slot-names property instead */
1395 	slots = of_get_property(np, "slot-names", &len);
1396 	if (slots && slots->count > 0) {
1397 		if (strcmp(slots->name, "IrDA") == 0)
1398 			uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1399 		else if (strcmp(slots->name, "Modem") == 0)
1400 			uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1401 	}
1402 	if (ZS_IS_IRDA(uap))
1403 		uap->port_type = PMAC_SCC_IRDA;
1404 	if (ZS_IS_INTMODEM(uap)) {
1405 		struct device_node* i2c_modem =
1406 			of_find_node_by_name(NULL, "i2c-modem");
1407 		if (i2c_modem) {
1408 			const char* mid =
1409 				of_get_property(i2c_modem, "modem-id", NULL);
1410 			if (mid) switch(*mid) {
1411 			case 0x04 :
1412 			case 0x05 :
1413 			case 0x07 :
1414 			case 0x08 :
1415 			case 0x0b :
1416 			case 0x0c :
1417 				uap->port_type = PMAC_SCC_I2S1;
1418 			}
1419 			printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
1420 				mid ? (*mid) : 0);
1421 			of_node_put(i2c_modem);
1422 		} else {
1423 			printk(KERN_INFO "pmac_zilog: serial modem detected\n");
1424 		}
1425 	}
1426 
1427 	/*
1428 	 * Init remaining bits of "port" structure
1429 	 */
1430 	uap->port.iotype = UPIO_MEM;
1431 	uap->port.irq = irq_of_parse_and_map(np, 0);
1432 	uap->port.uartclk = ZS_CLOCK;
1433 	uap->port.fifosize = 1;
1434 	uap->port.ops = &pmz_pops;
1435 	uap->port.type = PORT_PMAC_ZILOG;
1436 	uap->port.flags = 0;
1437 
1438 	/*
1439 	 * Fixup for the port on Gatwick for which the device-tree has
1440 	 * missing interrupts. Normally, the macio_dev would contain
1441 	 * fixed up interrupt info, but we use the device-tree directly
1442 	 * here due to early probing so we need the fixup too.
1443 	 */
1444 	if (uap->port.irq == 0 &&
1445 	    np->parent && np->parent->parent &&
1446 	    of_device_is_compatible(np->parent->parent, "gatwick")) {
1447 		/* IRQs on gatwick are offset by 64 */
1448 		uap->port.irq = irq_create_mapping(NULL, 64 + 15);
1449 	}
1450 
1451 	/* Setup some valid baud rate information in the register
1452 	 * shadows so we don't write crap there before baud rate is
1453 	 * first initialized.
1454 	 */
1455 	pmz_convert_to_zs(uap, CS8, 0, 9600);
1456 
1457 	return 0;
1458 }
1459 
1460 /*
1461  * Get rid of a port on module removal
1462  */
1463 static void pmz_dispose_port(struct uart_pmac_port *uap)
1464 {
1465 	struct device_node *np;
1466 
1467 	np = uap->node;
1468 	iounmap(uap->control_reg);
1469 	uap->node = NULL;
1470 	of_node_put(np);
1471 	memset(uap, 0, sizeof(struct uart_pmac_port));
1472 }
1473 
1474 /*
1475  * Called upon match with an escc node in the device-tree.
1476  */
1477 static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
1478 {
1479 	struct uart_pmac_port *uap;
1480 	int i;
1481 
1482 	/* Iterate the pmz_ports array to find a matching entry
1483 	 */
1484 	for (i = 0; i < MAX_ZS_PORTS; i++)
1485 		if (pmz_ports[i].node == mdev->ofdev.dev.of_node)
1486 			break;
1487 	if (i >= MAX_ZS_PORTS)
1488 		return -ENODEV;
1489 
1490 
1491 	uap = &pmz_ports[i];
1492 	uap->dev = mdev;
1493 	uap->port.dev = &mdev->ofdev.dev;
1494 	dev_set_drvdata(&mdev->ofdev.dev, uap);
1495 
1496 	/* We still activate the port even when failing to request resources
1497 	 * to work around bugs in ancient Apple device-trees
1498 	 */
1499 	if (macio_request_resources(uap->dev, "pmac_zilog"))
1500 		printk(KERN_WARNING "%pOFn: Failed to request resource"
1501 		       ", port still active\n",
1502 		       uap->node);
1503 	else
1504 		uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
1505 
1506 	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1507 }
1508 
1509 /*
1510  * That one should not be called, macio isn't really a hotswap device,
1511  * we don't expect one of those serial ports to go away...
1512  */
1513 static int pmz_detach(struct macio_dev *mdev)
1514 {
1515 	struct uart_pmac_port	*uap = dev_get_drvdata(&mdev->ofdev.dev);
1516 
1517 	if (!uap)
1518 		return -ENODEV;
1519 
1520 	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1521 
1522 	if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
1523 		macio_release_resources(uap->dev);
1524 		uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
1525 	}
1526 	dev_set_drvdata(&mdev->ofdev.dev, NULL);
1527 	uap->dev = NULL;
1528 	uap->port.dev = NULL;
1529 
1530 	return 0;
1531 }
1532 
1533 
1534 static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
1535 {
1536 	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1537 
1538 	if (uap == NULL) {
1539 		printk("HRM... pmz_suspend with NULL uap\n");
1540 		return 0;
1541 	}
1542 
1543 	uart_suspend_port(&pmz_uart_reg, &uap->port);
1544 
1545 	return 0;
1546 }
1547 
1548 
1549 static int pmz_resume(struct macio_dev *mdev)
1550 {
1551 	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1552 
1553 	if (uap == NULL)
1554 		return 0;
1555 
1556 	uart_resume_port(&pmz_uart_reg, &uap->port);
1557 
1558 	return 0;
1559 }
1560 
1561 /*
1562  * Probe all ports in the system and build the ports array, we register
1563  * with the serial layer later, so we get a proper struct device which
1564  * allows the tty to attach properly. This is later than it used to be
1565  * but the tty layer really wants it that way.
1566  */
1567 static int __init pmz_probe(void)
1568 {
1569 	struct device_node	*node_p, *node_a, *node_b, *np;
1570 	int			count = 0;
1571 	int			rc;
1572 
1573 	/*
1574 	 * Find all escc chips in the system
1575 	 */
1576 	for_each_node_by_name(node_p, "escc") {
1577 		/*
1578 		 * First get channel A/B node pointers
1579 		 *
1580 		 * TODO: Add routines with proper locking to do that...
1581 		 */
1582 		node_a = node_b = NULL;
1583 		for_each_child_of_node(node_p, np) {
1584 			if (of_node_name_prefix(np, "ch-a"))
1585 				node_a = of_node_get(np);
1586 			else if (of_node_name_prefix(np, "ch-b"))
1587 				node_b = of_node_get(np);
1588 		}
1589 		if (!node_a && !node_b) {
1590 			of_node_put(node_a);
1591 			of_node_put(node_b);
1592 			printk(KERN_ERR "pmac_zilog: missing node %c for escc %pOF\n",
1593 				(!node_a) ? 'a' : 'b', node_p);
1594 			continue;
1595 		}
1596 
1597 		/*
1598 		 * Fill basic fields in the port structures
1599 		 */
1600 		if (node_b != NULL) {
1601 			pmz_ports[count].mate		= &pmz_ports[count+1];
1602 			pmz_ports[count+1].mate		= &pmz_ports[count];
1603 		}
1604 		pmz_ports[count].flags		= PMACZILOG_FLAG_IS_CHANNEL_A;
1605 		pmz_ports[count].node		= node_a;
1606 		pmz_ports[count+1].node		= node_b;
1607 		pmz_ports[count].port.line	= count;
1608 		pmz_ports[count+1].port.line	= count+1;
1609 
1610 		/*
1611 		 * Setup the ports for real
1612 		 */
1613 		rc = pmz_init_port(&pmz_ports[count]);
1614 		if (rc == 0 && node_b != NULL)
1615 			rc = pmz_init_port(&pmz_ports[count+1]);
1616 		if (rc != 0) {
1617 			of_node_put(node_a);
1618 			of_node_put(node_b);
1619 			memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
1620 			memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
1621 			continue;
1622 		}
1623 		count += 2;
1624 	}
1625 	pmz_ports_count = count;
1626 
1627 	return 0;
1628 }
1629 
1630 #else
1631 
1632 /* On PCI PowerMacs, pmz_probe() does an explicit search of the OpenFirmware
1633  * tree to obtain the device_nodes needed to start the console before the
1634  * macio driver. On Macs without OpenFirmware, global platform_devices take
1635  * the place of those device_nodes.
1636  */
1637 extern struct platform_device scc_a_pdev, scc_b_pdev;
1638 
1639 static int __init pmz_init_port(struct uart_pmac_port *uap)
1640 {
1641 	struct resource *r_ports;
1642 	int irq;
1643 
1644 	r_ports = platform_get_resource(uap->pdev, IORESOURCE_MEM, 0);
1645 	if (!r_ports)
1646 		return -ENODEV;
1647 
1648 	irq = platform_get_irq(uap->pdev, 0);
1649 	if (irq < 0)
1650 		return irq;
1651 
1652 	uap->port.mapbase  = r_ports->start;
1653 	uap->port.membase  = (unsigned char __iomem *) r_ports->start;
1654 	uap->port.iotype   = UPIO_MEM;
1655 	uap->port.irq      = irq;
1656 	uap->port.uartclk  = ZS_CLOCK;
1657 	uap->port.fifosize = 1;
1658 	uap->port.ops      = &pmz_pops;
1659 	uap->port.type     = PORT_PMAC_ZILOG;
1660 	uap->port.flags    = 0;
1661 
1662 	uap->control_reg   = uap->port.membase;
1663 	uap->data_reg      = uap->control_reg + 4;
1664 	uap->port_type     = 0;
1665 	uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PMACZILOG_CONSOLE);
1666 
1667 	pmz_convert_to_zs(uap, CS8, 0, 9600);
1668 
1669 	return 0;
1670 }
1671 
1672 static int __init pmz_probe(void)
1673 {
1674 	int err;
1675 
1676 	pmz_ports_count = 0;
1677 
1678 	pmz_ports[0].port.line = 0;
1679 	pmz_ports[0].flags     = PMACZILOG_FLAG_IS_CHANNEL_A;
1680 	pmz_ports[0].pdev      = &scc_a_pdev;
1681 	err = pmz_init_port(&pmz_ports[0]);
1682 	if (err)
1683 		return err;
1684 	pmz_ports_count++;
1685 
1686 	pmz_ports[0].mate      = &pmz_ports[1];
1687 	pmz_ports[1].mate      = &pmz_ports[0];
1688 	pmz_ports[1].port.line = 1;
1689 	pmz_ports[1].flags     = 0;
1690 	pmz_ports[1].pdev      = &scc_b_pdev;
1691 	err = pmz_init_port(&pmz_ports[1]);
1692 	if (err)
1693 		return err;
1694 	pmz_ports_count++;
1695 
1696 	return 0;
1697 }
1698 
1699 static void pmz_dispose_port(struct uart_pmac_port *uap)
1700 {
1701 	memset(uap, 0, sizeof(struct uart_pmac_port));
1702 }
1703 
1704 static int __init pmz_attach(struct platform_device *pdev)
1705 {
1706 	struct uart_pmac_port *uap;
1707 	int i;
1708 
1709 	/* Iterate the pmz_ports array to find a matching entry */
1710 	for (i = 0; i < pmz_ports_count; i++)
1711 		if (pmz_ports[i].pdev == pdev)
1712 			break;
1713 	if (i >= pmz_ports_count)
1714 		return -ENODEV;
1715 
1716 	uap = &pmz_ports[i];
1717 	uap->port.dev = &pdev->dev;
1718 	platform_set_drvdata(pdev, uap);
1719 
1720 	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1721 }
1722 
1723 static int __exit pmz_detach(struct platform_device *pdev)
1724 {
1725 	struct uart_pmac_port *uap = platform_get_drvdata(pdev);
1726 
1727 	if (!uap)
1728 		return -ENODEV;
1729 
1730 	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1731 
1732 	uap->port.dev = NULL;
1733 
1734 	return 0;
1735 }
1736 
1737 #endif /* !CONFIG_PPC_PMAC */
1738 
1739 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1740 
1741 static void pmz_console_write(struct console *con, const char *s, unsigned int count);
1742 static int __init pmz_console_setup(struct console *co, char *options);
1743 
1744 static struct console pmz_console = {
1745 	.name	=	PMACZILOG_NAME,
1746 	.write	=	pmz_console_write,
1747 	.device	=	uart_console_device,
1748 	.setup	=	pmz_console_setup,
1749 	.flags	=	CON_PRINTBUFFER,
1750 	.index	=	-1,
1751 	.data   =	&pmz_uart_reg,
1752 };
1753 
1754 #define PMACZILOG_CONSOLE	&pmz_console
1755 #else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1756 #define PMACZILOG_CONSOLE	(NULL)
1757 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1758 
1759 /*
1760  * Register the driver, console driver and ports with the serial
1761  * core
1762  */
1763 static int __init pmz_register(void)
1764 {
1765 	pmz_uart_reg.nr = pmz_ports_count;
1766 	pmz_uart_reg.cons = PMACZILOG_CONSOLE;
1767 
1768 	/*
1769 	 * Register this driver with the serial core
1770 	 */
1771 	return uart_register_driver(&pmz_uart_reg);
1772 }
1773 
1774 #ifdef CONFIG_PPC_PMAC
1775 
1776 static const struct of_device_id pmz_match[] =
1777 {
1778 	{
1779 	.name		= "ch-a",
1780 	},
1781 	{
1782 	.name		= "ch-b",
1783 	},
1784 	{},
1785 };
1786 MODULE_DEVICE_TABLE (of, pmz_match);
1787 
1788 static struct macio_driver pmz_driver = {
1789 	.driver = {
1790 		.name 		= "pmac_zilog",
1791 		.owner		= THIS_MODULE,
1792 		.of_match_table	= pmz_match,
1793 	},
1794 	.probe		= pmz_attach,
1795 	.remove		= pmz_detach,
1796 	.suspend	= pmz_suspend,
1797 	.resume		= pmz_resume,
1798 };
1799 
1800 #else
1801 
1802 static struct platform_driver pmz_driver = {
1803 	.remove		= __exit_p(pmz_detach),
1804 	.driver		= {
1805 		.name		= "scc",
1806 	},
1807 };
1808 
1809 #endif /* !CONFIG_PPC_PMAC */
1810 
1811 static int __init init_pmz(void)
1812 {
1813 	int rc, i;
1814 
1815 	/*
1816 	 * First, we need to do a direct OF-based probe pass. We
1817 	 * do that because we want serial console up before the
1818 	 * macio stuffs calls us back, and since that makes it
1819 	 * easier to pass the proper number of channels to
1820 	 * uart_register_driver()
1821 	 */
1822 	if (pmz_ports_count == 0)
1823 		pmz_probe();
1824 
1825 	/*
1826 	 * Bail early if no port found
1827 	 */
1828 	if (pmz_ports_count == 0)
1829 		return -ENODEV;
1830 
1831 	/*
1832 	 * Now we register with the serial layer
1833 	 */
1834 	rc = pmz_register();
1835 	if (rc) {
1836 		printk(KERN_ERR
1837 			"pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"
1838 		 	"pmac_zilog: Did another serial driver already claim the minors?\n");
1839 		/* effectively "pmz_unprobe()" */
1840 		for (i=0; i < pmz_ports_count; i++)
1841 			pmz_dispose_port(&pmz_ports[i]);
1842 		return rc;
1843 	}
1844 
1845 	/*
1846 	 * Then we register the macio driver itself
1847 	 */
1848 #ifdef CONFIG_PPC_PMAC
1849 	return macio_register_driver(&pmz_driver);
1850 #else
1851 	return platform_driver_probe(&pmz_driver, pmz_attach);
1852 #endif
1853 }
1854 
1855 static void __exit exit_pmz(void)
1856 {
1857 	int i;
1858 
1859 #ifdef CONFIG_PPC_PMAC
1860 	/* Get rid of macio-driver (detach from macio) */
1861 	macio_unregister_driver(&pmz_driver);
1862 #else
1863 	platform_driver_unregister(&pmz_driver);
1864 #endif
1865 
1866 	for (i = 0; i < pmz_ports_count; i++) {
1867 		struct uart_pmac_port *uport = &pmz_ports[i];
1868 #ifdef CONFIG_PPC_PMAC
1869 		if (uport->node != NULL)
1870 			pmz_dispose_port(uport);
1871 #else
1872 		if (uport->pdev != NULL)
1873 			pmz_dispose_port(uport);
1874 #endif
1875 	}
1876 	/* Unregister UART driver */
1877 	uart_unregister_driver(&pmz_uart_reg);
1878 }
1879 
1880 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1881 
1882 static void pmz_console_putchar(struct uart_port *port, unsigned char ch)
1883 {
1884 	struct uart_pmac_port *uap =
1885 		container_of(port, struct uart_pmac_port, port);
1886 
1887 	/* Wait for the transmit buffer to empty. */
1888 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1889 		udelay(5);
1890 	write_zsdata(uap, ch);
1891 }
1892 
1893 /*
1894  * Print a string to the serial port trying not to disturb
1895  * any possible real use of the port...
1896  */
1897 static void pmz_console_write(struct console *con, const char *s, unsigned int count)
1898 {
1899 	struct uart_pmac_port *uap = &pmz_ports[con->index];
1900 	unsigned long flags;
1901 
1902 	spin_lock_irqsave(&uap->port.lock, flags);
1903 
1904 	/* Turn of interrupts and enable the transmitter. */
1905 	write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);
1906 	write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);
1907 
1908 	uart_console_write(&uap->port, s, count, pmz_console_putchar);
1909 
1910 	/* Restore the values in the registers. */
1911 	write_zsreg(uap, R1, uap->curregs[1]);
1912 	/* Don't disable the transmitter. */
1913 
1914 	spin_unlock_irqrestore(&uap->port.lock, flags);
1915 }
1916 
1917 /*
1918  * Setup the serial console
1919  */
1920 static int __init pmz_console_setup(struct console *co, char *options)
1921 {
1922 	struct uart_pmac_port *uap;
1923 	struct uart_port *port;
1924 	int baud = 38400;
1925 	int bits = 8;
1926 	int parity = 'n';
1927 	int flow = 'n';
1928 	unsigned long pwr_delay;
1929 
1930 	/*
1931 	 * XServe's default to 57600 bps
1932 	 */
1933 	if (of_machine_is_compatible("RackMac1,1")
1934 	    || of_machine_is_compatible("RackMac1,2")
1935 	    || of_machine_is_compatible("MacRISC4"))
1936 		baud = 57600;
1937 
1938 	/*
1939 	 * Check whether an invalid uart number has been specified, and
1940 	 * if so, search for the first available port that does have
1941 	 * console support.
1942 	 */
1943 	if (co->index >= pmz_ports_count)
1944 		co->index = 0;
1945 	uap = &pmz_ports[co->index];
1946 #ifdef CONFIG_PPC_PMAC
1947 	if (uap->node == NULL)
1948 		return -ENODEV;
1949 #else
1950 	if (uap->pdev == NULL)
1951 		return -ENODEV;
1952 #endif
1953 	port = &uap->port;
1954 
1955 	/*
1956 	 * Mark port as beeing a console
1957 	 */
1958 	uap->flags |= PMACZILOG_FLAG_IS_CONS;
1959 
1960 	/*
1961 	 * Temporary fix for uart layer who didn't setup the spinlock yet
1962 	 */
1963 	spin_lock_init(&port->lock);
1964 
1965 	/*
1966 	 * Enable the hardware
1967 	 */
1968 	pwr_delay = __pmz_startup(uap);
1969 	if (pwr_delay)
1970 		mdelay(pwr_delay);
1971 
1972 	if (options)
1973 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1974 
1975 	return uart_set_options(port, co, baud, parity, bits, flow);
1976 }
1977 
1978 static int __init pmz_console_init(void)
1979 {
1980 	/* Probe ports */
1981 	pmz_probe();
1982 
1983 	if (pmz_ports_count == 0)
1984 		return -ENODEV;
1985 
1986 	/* TODO: Autoprobe console based on OF */
1987 	/* pmz_console.index = i; */
1988 	register_console(&pmz_console);
1989 
1990 	return 0;
1991 
1992 }
1993 console_initcall(pmz_console_init);
1994 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1995 
1996 module_init(init_pmz);
1997 module_exit(exit_pmz);
1998