xref: /openbmc/linux/drivers/tty/serial/pmac_zilog.c (revision 81d67439)
1 /*
2  * Driver for PowerMac Z85c30 based ESCC cell found in the
3  * "macio" ASICs of various PowerMac models
4  *
5  * Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org)
6  *
7  * Derived from drivers/macintosh/macserial.c by Paul Mackerras
8  * and drivers/serial/sunzilog.c by David S. Miller
9  *
10  * Hrm... actually, I ripped most of sunzilog (Thanks David !) and
11  * adapted special tweaks needed for us. I don't think it's worth
12  * merging back those though. The DMA code still has to get in
13  * and once done, I expect that driver to remain fairly stable in
14  * the long term, unless we change the driver model again...
15  *
16  * This program is free software; you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License as published by
18  * the Free Software Foundation; either version 2 of the License, or
19  * (at your option) any later version.
20  *
21  * This program is distributed in the hope that it will be useful,
22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24  * GNU General Public License for more details.
25  *
26  * You should have received a copy of the GNU General Public License
27  * along with this program; if not, write to the Free Software
28  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
29  *
30  * 2004-08-06 Harald Welte <laforge@gnumonks.org>
31  *	- Enable BREAK interrupt
32  *	- Add support for sysreq
33  *
34  * TODO:   - Add DMA support
35  *         - Defer port shutdown to a few seconds after close
36  *         - maybe put something right into uap->clk_divisor
37  */
38 
39 #undef DEBUG
40 #undef DEBUG_HARD
41 #undef USE_CTRL_O_SYSRQ
42 
43 #include <linux/module.h>
44 #include <linux/tty.h>
45 
46 #include <linux/tty_flip.h>
47 #include <linux/major.h>
48 #include <linux/string.h>
49 #include <linux/fcntl.h>
50 #include <linux/mm.h>
51 #include <linux/kernel.h>
52 #include <linux/delay.h>
53 #include <linux/init.h>
54 #include <linux/console.h>
55 #include <linux/adb.h>
56 #include <linux/pmu.h>
57 #include <linux/bitops.h>
58 #include <linux/sysrq.h>
59 #include <linux/mutex.h>
60 #include <asm/sections.h>
61 #include <asm/io.h>
62 #include <asm/irq.h>
63 
64 #ifdef CONFIG_PPC_PMAC
65 #include <asm/prom.h>
66 #include <asm/machdep.h>
67 #include <asm/pmac_feature.h>
68 #include <asm/dbdma.h>
69 #include <asm/macio.h>
70 #else
71 #include <linux/platform_device.h>
72 #define of_machine_is_compatible(x) (0)
73 #endif
74 
75 #if defined (CONFIG_SERIAL_PMACZILOG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
76 #define SUPPORT_SYSRQ
77 #endif
78 
79 #include <linux/serial.h>
80 #include <linux/serial_core.h>
81 
82 #include "pmac_zilog.h"
83 
84 /* Not yet implemented */
85 #undef HAS_DBDMA
86 
87 static char version[] __initdata = "pmac_zilog: 0.6 (Benjamin Herrenschmidt <benh@kernel.crashing.org>)";
88 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
89 MODULE_DESCRIPTION("Driver for the Mac and PowerMac serial ports.");
90 MODULE_LICENSE("GPL");
91 
92 #ifdef CONFIG_SERIAL_PMACZILOG_TTYS
93 #define PMACZILOG_MAJOR		TTY_MAJOR
94 #define PMACZILOG_MINOR		64
95 #define PMACZILOG_NAME		"ttyS"
96 #else
97 #define PMACZILOG_MAJOR		204
98 #define PMACZILOG_MINOR		192
99 #define PMACZILOG_NAME		"ttyPZ"
100 #endif
101 
102 
103 /*
104  * For the sake of early serial console, we can do a pre-probe
105  * (optional) of the ports at rather early boot time.
106  */
107 static struct uart_pmac_port	pmz_ports[MAX_ZS_PORTS];
108 static int			pmz_ports_count;
109 static DEFINE_MUTEX(pmz_irq_mutex);
110 
111 static struct uart_driver pmz_uart_reg = {
112 	.owner		=	THIS_MODULE,
113 	.driver_name	=	PMACZILOG_NAME,
114 	.dev_name	=	PMACZILOG_NAME,
115 	.major		=	PMACZILOG_MAJOR,
116 	.minor		=	PMACZILOG_MINOR,
117 };
118 
119 
120 /*
121  * Load all registers to reprogram the port
122  * This function must only be called when the TX is not busy.  The UART
123  * port lock must be held and local interrupts disabled.
124  */
125 static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
126 {
127 	int i;
128 
129 	if (ZS_IS_ASLEEP(uap))
130 		return;
131 
132 	/* Let pending transmits finish.  */
133 	for (i = 0; i < 1000; i++) {
134 		unsigned char stat = read_zsreg(uap, R1);
135 		if (stat & ALL_SNT)
136 			break;
137 		udelay(100);
138 	}
139 
140 	ZS_CLEARERR(uap);
141 	zssync(uap);
142 	ZS_CLEARFIFO(uap);
143 	zssync(uap);
144 	ZS_CLEARERR(uap);
145 
146 	/* Disable all interrupts.  */
147 	write_zsreg(uap, R1,
148 		    regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
149 
150 	/* Set parity, sync config, stop bits, and clock divisor.  */
151 	write_zsreg(uap, R4, regs[R4]);
152 
153 	/* Set misc. TX/RX control bits.  */
154 	write_zsreg(uap, R10, regs[R10]);
155 
156 	/* Set TX/RX controls sans the enable bits.  */
157 	write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
158 	write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
159 
160 	/* now set R7 "prime" on ESCC */
161 	write_zsreg(uap, R15, regs[R15] | EN85C30);
162 	write_zsreg(uap, R7, regs[R7P]);
163 
164 	/* make sure we use R7 "non-prime" on ESCC */
165 	write_zsreg(uap, R15, regs[R15] & ~EN85C30);
166 
167 	/* Synchronous mode config.  */
168 	write_zsreg(uap, R6, regs[R6]);
169 	write_zsreg(uap, R7, regs[R7]);
170 
171 	/* Disable baud generator.  */
172 	write_zsreg(uap, R14, regs[R14] & ~BRENAB);
173 
174 	/* Clock mode control.  */
175 	write_zsreg(uap, R11, regs[R11]);
176 
177 	/* Lower and upper byte of baud rate generator divisor.  */
178 	write_zsreg(uap, R12, regs[R12]);
179 	write_zsreg(uap, R13, regs[R13]);
180 
181 	/* Now rewrite R14, with BRENAB (if set).  */
182 	write_zsreg(uap, R14, regs[R14]);
183 
184 	/* Reset external status interrupts.  */
185 	write_zsreg(uap, R0, RES_EXT_INT);
186 	write_zsreg(uap, R0, RES_EXT_INT);
187 
188 	/* Rewrite R3/R5, this time without enables masked.  */
189 	write_zsreg(uap, R3, regs[R3]);
190 	write_zsreg(uap, R5, regs[R5]);
191 
192 	/* Rewrite R1, this time without IRQ enabled masked.  */
193 	write_zsreg(uap, R1, regs[R1]);
194 
195 	/* Enable interrupts */
196 	write_zsreg(uap, R9, regs[R9]);
197 }
198 
199 /*
200  * We do like sunzilog to avoid disrupting pending Tx
201  * Reprogram the Zilog channel HW registers with the copies found in the
202  * software state struct.  If the transmitter is busy, we defer this update
203  * until the next TX complete interrupt.  Else, we do it right now.
204  *
205  * The UART port lock must be held and local interrupts disabled.
206  */
207 static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
208 {
209 	if (!ZS_REGS_HELD(uap)) {
210 		if (ZS_TX_ACTIVE(uap)) {
211 			uap->flags |= PMACZILOG_FLAG_REGS_HELD;
212 		} else {
213 			pmz_debug("pmz: maybe_update_regs: updating\n");
214 			pmz_load_zsregs(uap, uap->curregs);
215 		}
216 	}
217 }
218 
219 static struct tty_struct *pmz_receive_chars(struct uart_pmac_port *uap)
220 {
221 	struct tty_struct *tty = NULL;
222 	unsigned char ch, r1, drop, error, flag;
223 	int loops = 0;
224 
225 	/* The interrupt can be enabled when the port isn't open, typically
226 	 * that happens when using one port is open and the other closed (stale
227 	 * interrupt) or when one port is used as a console.
228 	 */
229 	if (!ZS_IS_OPEN(uap)) {
230 		pmz_debug("pmz: draining input\n");
231 		/* Port is closed, drain input data */
232 		for (;;) {
233 			if ((++loops) > 1000)
234 				goto flood;
235 			(void)read_zsreg(uap, R1);
236 			write_zsreg(uap, R0, ERR_RES);
237 			(void)read_zsdata(uap);
238 			ch = read_zsreg(uap, R0);
239 			if (!(ch & Rx_CH_AV))
240 				break;
241 		}
242 		return NULL;
243 	}
244 
245 	/* Sanity check, make sure the old bug is no longer happening */
246 	if (uap->port.state == NULL || uap->port.state->port.tty == NULL) {
247 		WARN_ON(1);
248 		(void)read_zsdata(uap);
249 		return NULL;
250 	}
251 	tty = uap->port.state->port.tty;
252 
253 	while (1) {
254 		error = 0;
255 		drop = 0;
256 
257 		r1 = read_zsreg(uap, R1);
258 		ch = read_zsdata(uap);
259 
260 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
261 			write_zsreg(uap, R0, ERR_RES);
262 			zssync(uap);
263 		}
264 
265 		ch &= uap->parity_mask;
266 		if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
267 			uap->flags &= ~PMACZILOG_FLAG_BREAK;
268 		}
269 
270 #if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
271 #ifdef USE_CTRL_O_SYSRQ
272 		/* Handle the SysRq ^O Hack */
273 		if (ch == '\x0f') {
274 			uap->port.sysrq = jiffies + HZ*5;
275 			goto next_char;
276 		}
277 #endif /* USE_CTRL_O_SYSRQ */
278 		if (uap->port.sysrq) {
279 			int swallow;
280 			spin_unlock(&uap->port.lock);
281 			swallow = uart_handle_sysrq_char(&uap->port, ch);
282 			spin_lock(&uap->port.lock);
283 			if (swallow)
284 				goto next_char;
285 		}
286 #endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
287 
288 		/* A real serial line, record the character and status.  */
289 		if (drop)
290 			goto next_char;
291 
292 		flag = TTY_NORMAL;
293 		uap->port.icount.rx++;
294 
295 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
296 			error = 1;
297 			if (r1 & BRK_ABRT) {
298 				pmz_debug("pmz: got break !\n");
299 				r1 &= ~(PAR_ERR | CRC_ERR);
300 				uap->port.icount.brk++;
301 				if (uart_handle_break(&uap->port))
302 					goto next_char;
303 			}
304 			else if (r1 & PAR_ERR)
305 				uap->port.icount.parity++;
306 			else if (r1 & CRC_ERR)
307 				uap->port.icount.frame++;
308 			if (r1 & Rx_OVR)
309 				uap->port.icount.overrun++;
310 			r1 &= uap->port.read_status_mask;
311 			if (r1 & BRK_ABRT)
312 				flag = TTY_BREAK;
313 			else if (r1 & PAR_ERR)
314 				flag = TTY_PARITY;
315 			else if (r1 & CRC_ERR)
316 				flag = TTY_FRAME;
317 		}
318 
319 		if (uap->port.ignore_status_mask == 0xff ||
320 		    (r1 & uap->port.ignore_status_mask) == 0) {
321 			tty_insert_flip_char(tty, ch, flag);
322 		}
323 		if (r1 & Rx_OVR)
324 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
325 	next_char:
326 		/* We can get stuck in an infinite loop getting char 0 when the
327 		 * line is in a wrong HW state, we break that here.
328 		 * When that happens, I disable the receive side of the driver.
329 		 * Note that what I've been experiencing is a real irq loop where
330 		 * I'm getting flooded regardless of the actual port speed.
331 		 * Something strange is going on with the HW
332 		 */
333 		if ((++loops) > 1000)
334 			goto flood;
335 		ch = read_zsreg(uap, R0);
336 		if (!(ch & Rx_CH_AV))
337 			break;
338 	}
339 
340 	return tty;
341  flood:
342 	uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
343 	write_zsreg(uap, R1, uap->curregs[R1]);
344 	zssync(uap);
345 	pmz_error("pmz: rx irq flood !\n");
346 	return tty;
347 }
348 
349 static void pmz_status_handle(struct uart_pmac_port *uap)
350 {
351 	unsigned char status;
352 
353 	status = read_zsreg(uap, R0);
354 	write_zsreg(uap, R0, RES_EXT_INT);
355 	zssync(uap);
356 
357 	if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
358 		if (status & SYNC_HUNT)
359 			uap->port.icount.dsr++;
360 
361 		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
362 		 * But it does not tell us which bit has changed, we have to keep
363 		 * track of this ourselves.
364 		 * The CTS input is inverted for some reason.  -- paulus
365 		 */
366 		if ((status ^ uap->prev_status) & DCD)
367 			uart_handle_dcd_change(&uap->port,
368 					       (status & DCD));
369 		if ((status ^ uap->prev_status) & CTS)
370 			uart_handle_cts_change(&uap->port,
371 					       !(status & CTS));
372 
373 		wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
374 	}
375 
376 	if (status & BRK_ABRT)
377 		uap->flags |= PMACZILOG_FLAG_BREAK;
378 
379 	uap->prev_status = status;
380 }
381 
382 static void pmz_transmit_chars(struct uart_pmac_port *uap)
383 {
384 	struct circ_buf *xmit;
385 
386 	if (ZS_IS_ASLEEP(uap))
387 		return;
388 	if (ZS_IS_CONS(uap)) {
389 		unsigned char status = read_zsreg(uap, R0);
390 
391 		/* TX still busy?  Just wait for the next TX done interrupt.
392 		 *
393 		 * It can occur because of how we do serial console writes.  It would
394 		 * be nice to transmit console writes just like we normally would for
395 		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not
396 		 * easy because console writes cannot sleep.  One solution might be
397 		 * to poll on enough port->xmit space becoming free.  -DaveM
398 		 */
399 		if (!(status & Tx_BUF_EMP))
400 			return;
401 	}
402 
403 	uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
404 
405 	if (ZS_REGS_HELD(uap)) {
406 		pmz_load_zsregs(uap, uap->curregs);
407 		uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
408 	}
409 
410 	if (ZS_TX_STOPPED(uap)) {
411 		uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
412 		goto ack_tx_int;
413 	}
414 
415 	/* Under some circumstances, we see interrupts reported for
416 	 * a closed channel. The interrupt mask in R1 is clear, but
417 	 * R3 still signals the interrupts and we see them when taking
418 	 * an interrupt for the other channel (this could be a qemu
419 	 * bug but since the ESCC doc doesn't specify precsiely whether
420 	 * R3 interrup status bits are masked by R1 interrupt enable
421 	 * bits, better safe than sorry). --BenH.
422 	 */
423 	if (!ZS_IS_OPEN(uap))
424 		goto ack_tx_int;
425 
426 	if (uap->port.x_char) {
427 		uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
428 		write_zsdata(uap, uap->port.x_char);
429 		zssync(uap);
430 		uap->port.icount.tx++;
431 		uap->port.x_char = 0;
432 		return;
433 	}
434 
435 	if (uap->port.state == NULL)
436 		goto ack_tx_int;
437 	xmit = &uap->port.state->xmit;
438 	if (uart_circ_empty(xmit)) {
439 		uart_write_wakeup(&uap->port);
440 		goto ack_tx_int;
441 	}
442 	if (uart_tx_stopped(&uap->port))
443 		goto ack_tx_int;
444 
445 	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
446 	write_zsdata(uap, xmit->buf[xmit->tail]);
447 	zssync(uap);
448 
449 	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
450 	uap->port.icount.tx++;
451 
452 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
453 		uart_write_wakeup(&uap->port);
454 
455 	return;
456 
457 ack_tx_int:
458 	write_zsreg(uap, R0, RES_Tx_P);
459 	zssync(uap);
460 }
461 
462 /* Hrm... we register that twice, fixme later.... */
463 static irqreturn_t pmz_interrupt(int irq, void *dev_id)
464 {
465 	struct uart_pmac_port *uap = dev_id;
466 	struct uart_pmac_port *uap_a;
467 	struct uart_pmac_port *uap_b;
468 	int rc = IRQ_NONE;
469 	struct tty_struct *tty;
470 	u8 r3;
471 
472 	uap_a = pmz_get_port_A(uap);
473 	uap_b = uap_a->mate;
474 
475 	spin_lock(&uap_a->port.lock);
476 	r3 = read_zsreg(uap_a, R3);
477 
478 #ifdef DEBUG_HARD
479 	pmz_debug("irq, r3: %x\n", r3);
480 #endif
481 	/* Channel A */
482 	tty = NULL;
483 	if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
484 		write_zsreg(uap_a, R0, RES_H_IUS);
485 		zssync(uap_a);
486 		if (r3 & CHAEXT)
487 			pmz_status_handle(uap_a);
488 		if (r3 & CHARxIP)
489 			tty = pmz_receive_chars(uap_a);
490 		if (r3 & CHATxIP)
491 			pmz_transmit_chars(uap_a);
492 		rc = IRQ_HANDLED;
493 	}
494 	spin_unlock(&uap_a->port.lock);
495 	if (tty != NULL)
496 		tty_flip_buffer_push(tty);
497 
498 	if (uap_b->node == NULL)
499 		goto out;
500 
501 	spin_lock(&uap_b->port.lock);
502 	tty = NULL;
503 	if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
504 		write_zsreg(uap_b, R0, RES_H_IUS);
505 		zssync(uap_b);
506 		if (r3 & CHBEXT)
507 			pmz_status_handle(uap_b);
508 		if (r3 & CHBRxIP)
509 			tty = pmz_receive_chars(uap_b);
510 		if (r3 & CHBTxIP)
511 			pmz_transmit_chars(uap_b);
512 		rc = IRQ_HANDLED;
513 	}
514 	spin_unlock(&uap_b->port.lock);
515 	if (tty != NULL)
516 		tty_flip_buffer_push(tty);
517 
518  out:
519 #ifdef DEBUG_HARD
520 	pmz_debug("irq done.\n");
521 #endif
522 	return rc;
523 }
524 
525 /*
526  * Peek the status register, lock not held by caller
527  */
528 static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
529 {
530 	unsigned long flags;
531 	u8 status;
532 
533 	spin_lock_irqsave(&uap->port.lock, flags);
534 	status = read_zsreg(uap, R0);
535 	spin_unlock_irqrestore(&uap->port.lock, flags);
536 
537 	return status;
538 }
539 
540 /*
541  * Check if transmitter is empty
542  * The port lock is not held.
543  */
544 static unsigned int pmz_tx_empty(struct uart_port *port)
545 {
546 	struct uart_pmac_port *uap = to_pmz(port);
547 	unsigned char status;
548 
549 	if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
550 		return TIOCSER_TEMT;
551 
552 	status = pmz_peek_status(to_pmz(port));
553 	if (status & Tx_BUF_EMP)
554 		return TIOCSER_TEMT;
555 	return 0;
556 }
557 
558 /*
559  * Set Modem Control (RTS & DTR) bits
560  * The port lock is held and interrupts are disabled.
561  * Note: Shall we really filter out RTS on external ports or
562  * should that be dealt at higher level only ?
563  */
564 static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
565 {
566 	struct uart_pmac_port *uap = to_pmz(port);
567 	unsigned char set_bits, clear_bits;
568 
569         /* Do nothing for irda for now... */
570 	if (ZS_IS_IRDA(uap))
571 		return;
572 	/* We get called during boot with a port not up yet */
573 	if (ZS_IS_ASLEEP(uap) ||
574 	    !(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
575 		return;
576 
577 	set_bits = clear_bits = 0;
578 
579 	if (ZS_IS_INTMODEM(uap)) {
580 		if (mctrl & TIOCM_RTS)
581 			set_bits |= RTS;
582 		else
583 			clear_bits |= RTS;
584 	}
585 	if (mctrl & TIOCM_DTR)
586 		set_bits |= DTR;
587 	else
588 		clear_bits |= DTR;
589 
590 	/* NOTE: Not subject to 'transmitter active' rule.  */
591 	uap->curregs[R5] |= set_bits;
592 	uap->curregs[R5] &= ~clear_bits;
593 	if (ZS_IS_ASLEEP(uap))
594 		return;
595 	write_zsreg(uap, R5, uap->curregs[R5]);
596 	pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
597 		  set_bits, clear_bits, uap->curregs[R5]);
598 	zssync(uap);
599 }
600 
601 /*
602  * Get Modem Control bits (only the input ones, the core will
603  * or that with a cached value of the control ones)
604  * The port lock is held and interrupts are disabled.
605  */
606 static unsigned int pmz_get_mctrl(struct uart_port *port)
607 {
608 	struct uart_pmac_port *uap = to_pmz(port);
609 	unsigned char status;
610 	unsigned int ret;
611 
612 	if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
613 		return 0;
614 
615 	status = read_zsreg(uap, R0);
616 
617 	ret = 0;
618 	if (status & DCD)
619 		ret |= TIOCM_CAR;
620 	if (status & SYNC_HUNT)
621 		ret |= TIOCM_DSR;
622 	if (!(status & CTS))
623 		ret |= TIOCM_CTS;
624 
625 	return ret;
626 }
627 
628 /*
629  * Stop TX side. Dealt like sunzilog at next Tx interrupt,
630  * though for DMA, we will have to do a bit more.
631  * The port lock is held and interrupts are disabled.
632  */
633 static void pmz_stop_tx(struct uart_port *port)
634 {
635 	to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
636 }
637 
638 /*
639  * Kick the Tx side.
640  * The port lock is held and interrupts are disabled.
641  */
642 static void pmz_start_tx(struct uart_port *port)
643 {
644 	struct uart_pmac_port *uap = to_pmz(port);
645 	unsigned char status;
646 
647 	pmz_debug("pmz: start_tx()\n");
648 
649 	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
650 	uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
651 
652 	if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
653 		return;
654 
655 	status = read_zsreg(uap, R0);
656 
657 	/* TX busy?  Just wait for the TX done interrupt.  */
658 	if (!(status & Tx_BUF_EMP))
659 		return;
660 
661 	/* Send the first character to jump-start the TX done
662 	 * IRQ sending engine.
663 	 */
664 	if (port->x_char) {
665 		write_zsdata(uap, port->x_char);
666 		zssync(uap);
667 		port->icount.tx++;
668 		port->x_char = 0;
669 	} else {
670 		struct circ_buf *xmit = &port->state->xmit;
671 
672 		write_zsdata(uap, xmit->buf[xmit->tail]);
673 		zssync(uap);
674 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
675 		port->icount.tx++;
676 
677 		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
678 			uart_write_wakeup(&uap->port);
679 	}
680 	pmz_debug("pmz: start_tx() done.\n");
681 }
682 
683 /*
684  * Stop Rx side, basically disable emitting of
685  * Rx interrupts on the port. We don't disable the rx
686  * side of the chip proper though
687  * The port lock is held.
688  */
689 static void pmz_stop_rx(struct uart_port *port)
690 {
691 	struct uart_pmac_port *uap = to_pmz(port);
692 
693 	if (ZS_IS_ASLEEP(uap) || uap->node == NULL)
694 		return;
695 
696 	pmz_debug("pmz: stop_rx()()\n");
697 
698 	/* Disable all RX interrupts.  */
699 	uap->curregs[R1] &= ~RxINT_MASK;
700 	pmz_maybe_update_regs(uap);
701 
702 	pmz_debug("pmz: stop_rx() done.\n");
703 }
704 
705 /*
706  * Enable modem status change interrupts
707  * The port lock is held.
708  */
709 static void pmz_enable_ms(struct uart_port *port)
710 {
711 	struct uart_pmac_port *uap = to_pmz(port);
712 	unsigned char new_reg;
713 
714 	if (ZS_IS_IRDA(uap) || uap->node == NULL)
715 		return;
716 	new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
717 	if (new_reg != uap->curregs[R15]) {
718 		uap->curregs[R15] = new_reg;
719 
720 		if (ZS_IS_ASLEEP(uap))
721 			return;
722 		/* NOTE: Not subject to 'transmitter active' rule. */
723 		write_zsreg(uap, R15, uap->curregs[R15]);
724 	}
725 }
726 
727 /*
728  * Control break state emission
729  * The port lock is not held.
730  */
731 static void pmz_break_ctl(struct uart_port *port, int break_state)
732 {
733 	struct uart_pmac_port *uap = to_pmz(port);
734 	unsigned char set_bits, clear_bits, new_reg;
735 	unsigned long flags;
736 
737 	if (uap->node == NULL)
738 		return;
739 	set_bits = clear_bits = 0;
740 
741 	if (break_state)
742 		set_bits |= SND_BRK;
743 	else
744 		clear_bits |= SND_BRK;
745 
746 	spin_lock_irqsave(&port->lock, flags);
747 
748 	new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
749 	if (new_reg != uap->curregs[R5]) {
750 		uap->curregs[R5] = new_reg;
751 
752 		/* NOTE: Not subject to 'transmitter active' rule. */
753 		if (ZS_IS_ASLEEP(uap)) {
754 			spin_unlock_irqrestore(&port->lock, flags);
755 			return;
756 		}
757 		write_zsreg(uap, R5, uap->curregs[R5]);
758 	}
759 
760 	spin_unlock_irqrestore(&port->lock, flags);
761 }
762 
763 #ifdef CONFIG_PPC_PMAC
764 
765 /*
766  * Turn power on or off to the SCC and associated stuff
767  * (port drivers, modem, IR port, etc.)
768  * Returns the number of milliseconds we should wait before
769  * trying to use the port.
770  */
771 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
772 {
773 	int delay = 0;
774 	int rc;
775 
776 	if (state) {
777 		rc = pmac_call_feature(
778 			PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
779 		pmz_debug("port power on result: %d\n", rc);
780 		if (ZS_IS_INTMODEM(uap)) {
781 			rc = pmac_call_feature(
782 				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
783 			delay = 2500;	/* wait for 2.5s before using */
784 			pmz_debug("modem power result: %d\n", rc);
785 		}
786 	} else {
787 		/* TODO: Make that depend on a timer, don't power down
788 		 * immediately
789 		 */
790 		if (ZS_IS_INTMODEM(uap)) {
791 			rc = pmac_call_feature(
792 				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
793 			pmz_debug("port power off result: %d\n", rc);
794 		}
795 		pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
796 	}
797 	return delay;
798 }
799 
800 #else
801 
802 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
803 {
804 	return 0;
805 }
806 
807 #endif /* !CONFIG_PPC_PMAC */
808 
809 /*
810  * FixZeroBug....Works around a bug in the SCC receiving channel.
811  * Inspired from Darwin code, 15 Sept. 2000  -DanM
812  *
813  * The following sequence prevents a problem that is seen with O'Hare ASICs
814  * (most versions -- also with some Heathrow and Hydra ASICs) where a zero
815  * at the input to the receiver becomes 'stuck' and locks up the receiver.
816  * This problem can occur as a result of a zero bit at the receiver input
817  * coincident with any of the following events:
818  *
819  *	The SCC is initialized (hardware or software).
820  *	A framing error is detected.
821  *	The clocking option changes from synchronous or X1 asynchronous
822  *		clocking to X16, X32, or X64 asynchronous clocking.
823  *	The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
824  *
825  * This workaround attempts to recover from the lockup condition by placing
826  * the SCC in synchronous loopback mode with a fast clock before programming
827  * any of the asynchronous modes.
828  */
829 static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
830 {
831 	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
832 	zssync(uap);
833 	udelay(10);
834 	write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
835 	zssync(uap);
836 
837 	write_zsreg(uap, 4, X1CLK | MONSYNC);
838 	write_zsreg(uap, 3, Rx8);
839 	write_zsreg(uap, 5, Tx8 | RTS);
840 	write_zsreg(uap, 9, NV);	/* Didn't we already do this? */
841 	write_zsreg(uap, 11, RCBR | TCBR);
842 	write_zsreg(uap, 12, 0);
843 	write_zsreg(uap, 13, 0);
844 	write_zsreg(uap, 14, (LOOPBAK | BRSRC));
845 	write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
846 	write_zsreg(uap, 3, Rx8 | RxENABLE);
847 	write_zsreg(uap, 0, RES_EXT_INT);
848 	write_zsreg(uap, 0, RES_EXT_INT);
849 	write_zsreg(uap, 0, RES_EXT_INT);	/* to kill some time */
850 
851 	/* The channel should be OK now, but it is probably receiving
852 	 * loopback garbage.
853 	 * Switch to asynchronous mode, disable the receiver,
854 	 * and discard everything in the receive buffer.
855 	 */
856 	write_zsreg(uap, 9, NV);
857 	write_zsreg(uap, 4, X16CLK | SB_MASK);
858 	write_zsreg(uap, 3, Rx8);
859 
860 	while (read_zsreg(uap, 0) & Rx_CH_AV) {
861 		(void)read_zsreg(uap, 8);
862 		write_zsreg(uap, 0, RES_EXT_INT);
863 		write_zsreg(uap, 0, ERR_RES);
864 	}
865 }
866 
867 /*
868  * Real startup routine, powers up the hardware and sets up
869  * the SCC. Returns a delay in ms where you need to wait before
870  * actually using the port, this is typically the internal modem
871  * powerup delay. This routine expect the lock to be taken.
872  */
873 static int __pmz_startup(struct uart_pmac_port *uap)
874 {
875 	int pwr_delay = 0;
876 
877 	memset(&uap->curregs, 0, sizeof(uap->curregs));
878 
879 	/* Power up the SCC & underlying hardware (modem/irda) */
880 	pwr_delay = pmz_set_scc_power(uap, 1);
881 
882 	/* Nice buggy HW ... */
883 	pmz_fix_zero_bug_scc(uap);
884 
885 	/* Reset the channel */
886 	uap->curregs[R9] = 0;
887 	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
888 	zssync(uap);
889 	udelay(10);
890 	write_zsreg(uap, 9, 0);
891 	zssync(uap);
892 
893 	/* Clear the interrupt registers */
894 	write_zsreg(uap, R1, 0);
895 	write_zsreg(uap, R0, ERR_RES);
896 	write_zsreg(uap, R0, ERR_RES);
897 	write_zsreg(uap, R0, RES_H_IUS);
898 	write_zsreg(uap, R0, RES_H_IUS);
899 
900 	/* Setup some valid baud rate */
901 	uap->curregs[R4] = X16CLK | SB1;
902 	uap->curregs[R3] = Rx8;
903 	uap->curregs[R5] = Tx8 | RTS;
904 	if (!ZS_IS_IRDA(uap))
905 		uap->curregs[R5] |= DTR;
906 	uap->curregs[R12] = 0;
907 	uap->curregs[R13] = 0;
908 	uap->curregs[R14] = BRENAB;
909 
910 	/* Clear handshaking, enable BREAK interrupts */
911 	uap->curregs[R15] = BRKIE;
912 
913 	/* Master interrupt enable */
914 	uap->curregs[R9] |= NV | MIE;
915 
916 	pmz_load_zsregs(uap, uap->curregs);
917 
918 	/* Enable receiver and transmitter.  */
919 	write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
920 	write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
921 
922 	/* Remember status for DCD/CTS changes */
923 	uap->prev_status = read_zsreg(uap, R0);
924 
925 	return pwr_delay;
926 }
927 
928 static void pmz_irda_reset(struct uart_pmac_port *uap)
929 {
930 	uap->curregs[R5] |= DTR;
931 	write_zsreg(uap, R5, uap->curregs[R5]);
932 	zssync(uap);
933 	mdelay(110);
934 	uap->curregs[R5] &= ~DTR;
935 	write_zsreg(uap, R5, uap->curregs[R5]);
936 	zssync(uap);
937 	mdelay(10);
938 }
939 
940 /*
941  * This is the "normal" startup routine, using the above one
942  * wrapped with the lock and doing a schedule delay
943  */
944 static int pmz_startup(struct uart_port *port)
945 {
946 	struct uart_pmac_port *uap = to_pmz(port);
947 	unsigned long flags;
948 	int pwr_delay = 0;
949 
950 	pmz_debug("pmz: startup()\n");
951 
952 	if (ZS_IS_ASLEEP(uap))
953 		return -EAGAIN;
954 	if (uap->node == NULL)
955 		return -ENODEV;
956 
957 	mutex_lock(&pmz_irq_mutex);
958 
959 	uap->flags |= PMACZILOG_FLAG_IS_OPEN;
960 
961 	/* A console is never powered down. Else, power up and
962 	 * initialize the chip
963 	 */
964 	if (!ZS_IS_CONS(uap)) {
965 		spin_lock_irqsave(&port->lock, flags);
966 		pwr_delay = __pmz_startup(uap);
967 		spin_unlock_irqrestore(&port->lock, flags);
968 	}
969 
970 	pmz_get_port_A(uap)->flags |= PMACZILOG_FLAG_IS_IRQ_ON;
971 	if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,
972 			"SCC", uap)) {
973 		pmz_error("Unable to register zs interrupt handler.\n");
974 		pmz_set_scc_power(uap, 0);
975 		mutex_unlock(&pmz_irq_mutex);
976 		return -ENXIO;
977 	}
978 
979 	mutex_unlock(&pmz_irq_mutex);
980 
981 	/* Right now, we deal with delay by blocking here, I'll be
982 	 * smarter later on
983 	 */
984 	if (pwr_delay != 0) {
985 		pmz_debug("pmz: delaying %d ms\n", pwr_delay);
986 		msleep(pwr_delay);
987 	}
988 
989 	/* IrDA reset is done now */
990 	if (ZS_IS_IRDA(uap))
991 		pmz_irda_reset(uap);
992 
993 	/* Enable interrupts emission from the chip */
994 	spin_lock_irqsave(&port->lock, flags);
995 	uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
996 	if (!ZS_IS_EXTCLK(uap))
997 		uap->curregs[R1] |= EXT_INT_ENAB;
998 	write_zsreg(uap, R1, uap->curregs[R1]);
999 	spin_unlock_irqrestore(&port->lock, flags);
1000 
1001 	pmz_debug("pmz: startup() done.\n");
1002 
1003 	return 0;
1004 }
1005 
1006 static void pmz_shutdown(struct uart_port *port)
1007 {
1008 	struct uart_pmac_port *uap = to_pmz(port);
1009 	unsigned long flags;
1010 
1011 	pmz_debug("pmz: shutdown()\n");
1012 
1013 	if (uap->node == NULL)
1014 		return;
1015 
1016 	mutex_lock(&pmz_irq_mutex);
1017 
1018 	/* Release interrupt handler */
1019 	free_irq(uap->port.irq, uap);
1020 
1021 	spin_lock_irqsave(&port->lock, flags);
1022 
1023 	uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
1024 
1025 	if (!ZS_IS_OPEN(uap->mate))
1026 		pmz_get_port_A(uap)->flags &= ~PMACZILOG_FLAG_IS_IRQ_ON;
1027 
1028 	/* Disable interrupts */
1029 	if (!ZS_IS_ASLEEP(uap)) {
1030 		uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
1031 		write_zsreg(uap, R1, uap->curregs[R1]);
1032 		zssync(uap);
1033 	}
1034 
1035 	if (ZS_IS_CONS(uap) || ZS_IS_ASLEEP(uap)) {
1036 		spin_unlock_irqrestore(&port->lock, flags);
1037 		mutex_unlock(&pmz_irq_mutex);
1038 		return;
1039 	}
1040 
1041 	/* Disable receiver and transmitter.  */
1042 	uap->curregs[R3] &= ~RxENABLE;
1043 	uap->curregs[R5] &= ~TxENABLE;
1044 
1045 	/* Disable all interrupts and BRK assertion.  */
1046 	uap->curregs[R5] &= ~SND_BRK;
1047 	pmz_maybe_update_regs(uap);
1048 
1049 	/* Shut the chip down */
1050 	pmz_set_scc_power(uap, 0);
1051 
1052 	spin_unlock_irqrestore(&port->lock, flags);
1053 
1054 	mutex_unlock(&pmz_irq_mutex);
1055 
1056 	pmz_debug("pmz: shutdown() done.\n");
1057 }
1058 
1059 /* Shared by TTY driver and serial console setup.  The port lock is held
1060  * and local interrupts are disabled.
1061  */
1062 static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
1063 			      unsigned int iflag, unsigned long baud)
1064 {
1065 	int brg;
1066 
1067 	/* Switch to external clocking for IrDA high clock rates. That
1068 	 * code could be re-used for Midi interfaces with different
1069 	 * multipliers
1070 	 */
1071 	if (baud >= 115200 && ZS_IS_IRDA(uap)) {
1072 		uap->curregs[R4] = X1CLK;
1073 		uap->curregs[R11] = RCTRxCP | TCTRxCP;
1074 		uap->curregs[R14] = 0; /* BRG off */
1075 		uap->curregs[R12] = 0;
1076 		uap->curregs[R13] = 0;
1077 		uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
1078 	} else {
1079 		switch (baud) {
1080 		case ZS_CLOCK/16:	/* 230400 */
1081 			uap->curregs[R4] = X16CLK;
1082 			uap->curregs[R11] = 0;
1083 			uap->curregs[R14] = 0;
1084 			break;
1085 		case ZS_CLOCK/32:	/* 115200 */
1086 			uap->curregs[R4] = X32CLK;
1087 			uap->curregs[R11] = 0;
1088 			uap->curregs[R14] = 0;
1089 			break;
1090 		default:
1091 			uap->curregs[R4] = X16CLK;
1092 			uap->curregs[R11] = TCBR | RCBR;
1093 			brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
1094 			uap->curregs[R12] = (brg & 255);
1095 			uap->curregs[R13] = ((brg >> 8) & 255);
1096 			uap->curregs[R14] = BRENAB;
1097 		}
1098 		uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
1099 	}
1100 
1101 	/* Character size, stop bits, and parity. */
1102 	uap->curregs[3] &= ~RxN_MASK;
1103 	uap->curregs[5] &= ~TxN_MASK;
1104 
1105 	switch (cflag & CSIZE) {
1106 	case CS5:
1107 		uap->curregs[3] |= Rx5;
1108 		uap->curregs[5] |= Tx5;
1109 		uap->parity_mask = 0x1f;
1110 		break;
1111 	case CS6:
1112 		uap->curregs[3] |= Rx6;
1113 		uap->curregs[5] |= Tx6;
1114 		uap->parity_mask = 0x3f;
1115 		break;
1116 	case CS7:
1117 		uap->curregs[3] |= Rx7;
1118 		uap->curregs[5] |= Tx7;
1119 		uap->parity_mask = 0x7f;
1120 		break;
1121 	case CS8:
1122 	default:
1123 		uap->curregs[3] |= Rx8;
1124 		uap->curregs[5] |= Tx8;
1125 		uap->parity_mask = 0xff;
1126 		break;
1127 	};
1128 	uap->curregs[4] &= ~(SB_MASK);
1129 	if (cflag & CSTOPB)
1130 		uap->curregs[4] |= SB2;
1131 	else
1132 		uap->curregs[4] |= SB1;
1133 	if (cflag & PARENB)
1134 		uap->curregs[4] |= PAR_ENAB;
1135 	else
1136 		uap->curregs[4] &= ~PAR_ENAB;
1137 	if (!(cflag & PARODD))
1138 		uap->curregs[4] |= PAR_EVEN;
1139 	else
1140 		uap->curregs[4] &= ~PAR_EVEN;
1141 
1142 	uap->port.read_status_mask = Rx_OVR;
1143 	if (iflag & INPCK)
1144 		uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
1145 	if (iflag & (BRKINT | PARMRK))
1146 		uap->port.read_status_mask |= BRK_ABRT;
1147 
1148 	uap->port.ignore_status_mask = 0;
1149 	if (iflag & IGNPAR)
1150 		uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
1151 	if (iflag & IGNBRK) {
1152 		uap->port.ignore_status_mask |= BRK_ABRT;
1153 		if (iflag & IGNPAR)
1154 			uap->port.ignore_status_mask |= Rx_OVR;
1155 	}
1156 
1157 	if ((cflag & CREAD) == 0)
1158 		uap->port.ignore_status_mask = 0xff;
1159 }
1160 
1161 
1162 /*
1163  * Set the irda codec on the imac to the specified baud rate.
1164  */
1165 static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
1166 {
1167 	u8 cmdbyte;
1168 	int t, version;
1169 
1170 	switch (*baud) {
1171 	/* SIR modes */
1172 	case 2400:
1173 		cmdbyte = 0x53;
1174 		break;
1175 	case 4800:
1176 		cmdbyte = 0x52;
1177 		break;
1178 	case 9600:
1179 		cmdbyte = 0x51;
1180 		break;
1181 	case 19200:
1182 		cmdbyte = 0x50;
1183 		break;
1184 	case 38400:
1185 		cmdbyte = 0x4f;
1186 		break;
1187 	case 57600:
1188 		cmdbyte = 0x4e;
1189 		break;
1190 	case 115200:
1191 		cmdbyte = 0x4d;
1192 		break;
1193 	/* The FIR modes aren't really supported at this point, how
1194 	 * do we select the speed ? via the FCR on KeyLargo ?
1195 	 */
1196 	case 1152000:
1197 		cmdbyte = 0;
1198 		break;
1199 	case 4000000:
1200 		cmdbyte = 0;
1201 		break;
1202 	default: /* 9600 */
1203 		cmdbyte = 0x51;
1204 		*baud = 9600;
1205 		break;
1206 	}
1207 
1208 	/* Wait for transmitter to drain */
1209 	t = 10000;
1210 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
1211 	       || (read_zsreg(uap, R1) & ALL_SNT) == 0) {
1212 		if (--t <= 0) {
1213 			pmz_error("transmitter didn't drain\n");
1214 			return;
1215 		}
1216 		udelay(10);
1217 	}
1218 
1219 	/* Drain the receiver too */
1220 	t = 100;
1221 	(void)read_zsdata(uap);
1222 	(void)read_zsdata(uap);
1223 	(void)read_zsdata(uap);
1224 	mdelay(10);
1225 	while (read_zsreg(uap, R0) & Rx_CH_AV) {
1226 		read_zsdata(uap);
1227 		mdelay(10);
1228 		if (--t <= 0) {
1229 			pmz_error("receiver didn't drain\n");
1230 			return;
1231 		}
1232 	}
1233 
1234 	/* Switch to command mode */
1235 	uap->curregs[R5] |= DTR;
1236 	write_zsreg(uap, R5, uap->curregs[R5]);
1237 	zssync(uap);
1238 	mdelay(1);
1239 
1240 	/* Switch SCC to 19200 */
1241 	pmz_convert_to_zs(uap, CS8, 0, 19200);
1242 	pmz_load_zsregs(uap, uap->curregs);
1243 	mdelay(1);
1244 
1245 	/* Write get_version command byte */
1246 	write_zsdata(uap, 1);
1247 	t = 5000;
1248 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1249 		if (--t <= 0) {
1250 			pmz_error("irda_setup timed out on get_version byte\n");
1251 			goto out;
1252 		}
1253 		udelay(10);
1254 	}
1255 	version = read_zsdata(uap);
1256 
1257 	if (version < 4) {
1258 		pmz_info("IrDA: dongle version %d not supported\n", version);
1259 		goto out;
1260 	}
1261 
1262 	/* Send speed mode */
1263 	write_zsdata(uap, cmdbyte);
1264 	t = 5000;
1265 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1266 		if (--t <= 0) {
1267 			pmz_error("irda_setup timed out on speed mode byte\n");
1268 			goto out;
1269 		}
1270 		udelay(10);
1271 	}
1272 	t = read_zsdata(uap);
1273 	if (t != cmdbyte)
1274 		pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
1275 
1276 	pmz_info("IrDA setup for %ld bps, dongle version: %d\n",
1277 		 *baud, version);
1278 
1279 	(void)read_zsdata(uap);
1280 	(void)read_zsdata(uap);
1281 	(void)read_zsdata(uap);
1282 
1283  out:
1284 	/* Switch back to data mode */
1285 	uap->curregs[R5] &= ~DTR;
1286 	write_zsreg(uap, R5, uap->curregs[R5]);
1287 	zssync(uap);
1288 
1289 	(void)read_zsdata(uap);
1290 	(void)read_zsdata(uap);
1291 	(void)read_zsdata(uap);
1292 }
1293 
1294 
1295 static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1296 			      struct ktermios *old)
1297 {
1298 	struct uart_pmac_port *uap = to_pmz(port);
1299 	unsigned long baud;
1300 
1301 	pmz_debug("pmz: set_termios()\n");
1302 
1303 	if (ZS_IS_ASLEEP(uap))
1304 		return;
1305 
1306 	memcpy(&uap->termios_cache, termios, sizeof(struct ktermios));
1307 
1308 	/* XXX Check which revs of machines actually allow 1 and 4Mb speeds
1309 	 * on the IR dongle. Note that the IRTTY driver currently doesn't know
1310 	 * about the FIR mode and high speed modes. So these are unused. For
1311 	 * implementing proper support for these, we should probably add some
1312 	 * DMA as well, at least on the Rx side, which isn't a simple thing
1313 	 * at this point.
1314 	 */
1315 	if (ZS_IS_IRDA(uap)) {
1316 		/* Calc baud rate */
1317 		baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
1318 		pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
1319 		/* Cet the irda codec to the right rate */
1320 		pmz_irda_setup(uap, &baud);
1321 		/* Set final baud rate */
1322 		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1323 		pmz_load_zsregs(uap, uap->curregs);
1324 		zssync(uap);
1325 	} else {
1326 		baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
1327 		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1328 		/* Make sure modem status interrupts are correctly configured */
1329 		if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
1330 			uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
1331 			uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
1332 		} else {
1333 			uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
1334 			uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
1335 		}
1336 
1337 		/* Load registers to the chip */
1338 		pmz_maybe_update_regs(uap);
1339 	}
1340 	uart_update_timeout(port, termios->c_cflag, baud);
1341 
1342 	pmz_debug("pmz: set_termios() done.\n");
1343 }
1344 
1345 /* The port lock is not held.  */
1346 static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1347 			    struct ktermios *old)
1348 {
1349 	struct uart_pmac_port *uap = to_pmz(port);
1350 	unsigned long flags;
1351 
1352 	spin_lock_irqsave(&port->lock, flags);
1353 
1354 	/* Disable IRQs on the port */
1355 	uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
1356 	write_zsreg(uap, R1, uap->curregs[R1]);
1357 
1358 	/* Setup new port configuration */
1359 	__pmz_set_termios(port, termios, old);
1360 
1361 	/* Re-enable IRQs on the port */
1362 	if (ZS_IS_OPEN(uap)) {
1363 		uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
1364 		if (!ZS_IS_EXTCLK(uap))
1365 			uap->curregs[R1] |= EXT_INT_ENAB;
1366 		write_zsreg(uap, R1, uap->curregs[R1]);
1367 	}
1368 	spin_unlock_irqrestore(&port->lock, flags);
1369 }
1370 
1371 static const char *pmz_type(struct uart_port *port)
1372 {
1373 	struct uart_pmac_port *uap = to_pmz(port);
1374 
1375 	if (ZS_IS_IRDA(uap))
1376 		return "Z85c30 ESCC - Infrared port";
1377 	else if (ZS_IS_INTMODEM(uap))
1378 		return "Z85c30 ESCC - Internal modem";
1379 	return "Z85c30 ESCC - Serial port";
1380 }
1381 
1382 /* We do not request/release mappings of the registers here, this
1383  * happens at early serial probe time.
1384  */
1385 static void pmz_release_port(struct uart_port *port)
1386 {
1387 }
1388 
1389 static int pmz_request_port(struct uart_port *port)
1390 {
1391 	return 0;
1392 }
1393 
1394 /* These do not need to do anything interesting either.  */
1395 static void pmz_config_port(struct uart_port *port, int flags)
1396 {
1397 }
1398 
1399 /* We do not support letting the user mess with the divisor, IRQ, etc. */
1400 static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
1401 {
1402 	return -EINVAL;
1403 }
1404 
1405 #ifdef CONFIG_CONSOLE_POLL
1406 
1407 static int pmz_poll_get_char(struct uart_port *port)
1408 {
1409 	struct uart_pmac_port *uap = (struct uart_pmac_port *)port;
1410 
1411 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0)
1412 		udelay(5);
1413 	return read_zsdata(uap);
1414 }
1415 
1416 static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
1417 {
1418 	struct uart_pmac_port *uap = (struct uart_pmac_port *)port;
1419 
1420 	/* Wait for the transmit buffer to empty. */
1421 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1422 		udelay(5);
1423 	write_zsdata(uap, c);
1424 }
1425 
1426 #endif /* CONFIG_CONSOLE_POLL */
1427 
1428 static struct uart_ops pmz_pops = {
1429 	.tx_empty	=	pmz_tx_empty,
1430 	.set_mctrl	=	pmz_set_mctrl,
1431 	.get_mctrl	=	pmz_get_mctrl,
1432 	.stop_tx	=	pmz_stop_tx,
1433 	.start_tx	=	pmz_start_tx,
1434 	.stop_rx	=	pmz_stop_rx,
1435 	.enable_ms	=	pmz_enable_ms,
1436 	.break_ctl	=	pmz_break_ctl,
1437 	.startup	=	pmz_startup,
1438 	.shutdown	=	pmz_shutdown,
1439 	.set_termios	=	pmz_set_termios,
1440 	.type		=	pmz_type,
1441 	.release_port	=	pmz_release_port,
1442 	.request_port	=	pmz_request_port,
1443 	.config_port	=	pmz_config_port,
1444 	.verify_port	=	pmz_verify_port,
1445 #ifdef CONFIG_CONSOLE_POLL
1446 	.poll_get_char	=	pmz_poll_get_char,
1447 	.poll_put_char	=	pmz_poll_put_char,
1448 #endif
1449 };
1450 
1451 #ifdef CONFIG_PPC_PMAC
1452 
1453 /*
1454  * Setup one port structure after probing, HW is down at this point,
1455  * Unlike sunzilog, we don't need to pre-init the spinlock as we don't
1456  * register our console before uart_add_one_port() is called
1457  */
1458 static int __init pmz_init_port(struct uart_pmac_port *uap)
1459 {
1460 	struct device_node *np = uap->node;
1461 	const char *conn;
1462 	const struct slot_names_prop {
1463 		int	count;
1464 		char	name[1];
1465 	} *slots;
1466 	int len;
1467 	struct resource r_ports, r_rxdma, r_txdma;
1468 
1469 	/*
1470 	 * Request & map chip registers
1471 	 */
1472 	if (of_address_to_resource(np, 0, &r_ports))
1473 		return -ENODEV;
1474 	uap->port.mapbase = r_ports.start;
1475 	uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
1476 
1477 	uap->control_reg = uap->port.membase;
1478 	uap->data_reg = uap->control_reg + 0x10;
1479 
1480 	/*
1481 	 * Request & map DBDMA registers
1482 	 */
1483 #ifdef HAS_DBDMA
1484 	if (of_address_to_resource(np, 1, &r_txdma) == 0 &&
1485 	    of_address_to_resource(np, 2, &r_rxdma) == 0)
1486 		uap->flags |= PMACZILOG_FLAG_HAS_DMA;
1487 #else
1488 	memset(&r_txdma, 0, sizeof(struct resource));
1489 	memset(&r_rxdma, 0, sizeof(struct resource));
1490 #endif
1491 	if (ZS_HAS_DMA(uap)) {
1492 		uap->tx_dma_regs = ioremap(r_txdma.start, 0x100);
1493 		if (uap->tx_dma_regs == NULL) {
1494 			uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
1495 			goto no_dma;
1496 		}
1497 		uap->rx_dma_regs = ioremap(r_rxdma.start, 0x100);
1498 		if (uap->rx_dma_regs == NULL) {
1499 			iounmap(uap->tx_dma_regs);
1500 			uap->tx_dma_regs = NULL;
1501 			uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
1502 			goto no_dma;
1503 		}
1504 		uap->tx_dma_irq = irq_of_parse_and_map(np, 1);
1505 		uap->rx_dma_irq = irq_of_parse_and_map(np, 2);
1506 	}
1507 no_dma:
1508 
1509 	/*
1510 	 * Detect port type
1511 	 */
1512 	if (of_device_is_compatible(np, "cobalt"))
1513 		uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1514 	conn = of_get_property(np, "AAPL,connector", &len);
1515 	if (conn && (strcmp(conn, "infrared") == 0))
1516 		uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1517 	uap->port_type = PMAC_SCC_ASYNC;
1518 	/* 1999 Powerbook G3 has slot-names property instead */
1519 	slots = of_get_property(np, "slot-names", &len);
1520 	if (slots && slots->count > 0) {
1521 		if (strcmp(slots->name, "IrDA") == 0)
1522 			uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1523 		else if (strcmp(slots->name, "Modem") == 0)
1524 			uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1525 	}
1526 	if (ZS_IS_IRDA(uap))
1527 		uap->port_type = PMAC_SCC_IRDA;
1528 	if (ZS_IS_INTMODEM(uap)) {
1529 		struct device_node* i2c_modem =
1530 			of_find_node_by_name(NULL, "i2c-modem");
1531 		if (i2c_modem) {
1532 			const char* mid =
1533 				of_get_property(i2c_modem, "modem-id", NULL);
1534 			if (mid) switch(*mid) {
1535 			case 0x04 :
1536 			case 0x05 :
1537 			case 0x07 :
1538 			case 0x08 :
1539 			case 0x0b :
1540 			case 0x0c :
1541 				uap->port_type = PMAC_SCC_I2S1;
1542 			}
1543 			printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
1544 				mid ? (*mid) : 0);
1545 			of_node_put(i2c_modem);
1546 		} else {
1547 			printk(KERN_INFO "pmac_zilog: serial modem detected\n");
1548 		}
1549 	}
1550 
1551 	/*
1552 	 * Init remaining bits of "port" structure
1553 	 */
1554 	uap->port.iotype = UPIO_MEM;
1555 	uap->port.irq = irq_of_parse_and_map(np, 0);
1556 	uap->port.uartclk = ZS_CLOCK;
1557 	uap->port.fifosize = 1;
1558 	uap->port.ops = &pmz_pops;
1559 	uap->port.type = PORT_PMAC_ZILOG;
1560 	uap->port.flags = 0;
1561 
1562 	/*
1563 	 * Fixup for the port on Gatwick for which the device-tree has
1564 	 * missing interrupts. Normally, the macio_dev would contain
1565 	 * fixed up interrupt info, but we use the device-tree directly
1566 	 * here due to early probing so we need the fixup too.
1567 	 */
1568 	if (uap->port.irq == NO_IRQ &&
1569 	    np->parent && np->parent->parent &&
1570 	    of_device_is_compatible(np->parent->parent, "gatwick")) {
1571 		/* IRQs on gatwick are offset by 64 */
1572 		uap->port.irq = irq_create_mapping(NULL, 64 + 15);
1573 		uap->tx_dma_irq = irq_create_mapping(NULL, 64 + 4);
1574 		uap->rx_dma_irq = irq_create_mapping(NULL, 64 + 5);
1575 	}
1576 
1577 	/* Setup some valid baud rate information in the register
1578 	 * shadows so we don't write crap there before baud rate is
1579 	 * first initialized.
1580 	 */
1581 	pmz_convert_to_zs(uap, CS8, 0, 9600);
1582 
1583 	return 0;
1584 }
1585 
1586 /*
1587  * Get rid of a port on module removal
1588  */
1589 static void pmz_dispose_port(struct uart_pmac_port *uap)
1590 {
1591 	struct device_node *np;
1592 
1593 	np = uap->node;
1594 	iounmap(uap->rx_dma_regs);
1595 	iounmap(uap->tx_dma_regs);
1596 	iounmap(uap->control_reg);
1597 	uap->node = NULL;
1598 	of_node_put(np);
1599 	memset(uap, 0, sizeof(struct uart_pmac_port));
1600 }
1601 
1602 /*
1603  * Called upon match with an escc node in the device-tree.
1604  */
1605 static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
1606 {
1607 	int i;
1608 
1609 	/* Iterate the pmz_ports array to find a matching entry
1610 	 */
1611 	for (i = 0; i < MAX_ZS_PORTS; i++)
1612 		if (pmz_ports[i].node == mdev->ofdev.dev.of_node) {
1613 			struct uart_pmac_port *uap = &pmz_ports[i];
1614 
1615 			uap->dev = mdev;
1616 			dev_set_drvdata(&mdev->ofdev.dev, uap);
1617 			if (macio_request_resources(uap->dev, "pmac_zilog"))
1618 				printk(KERN_WARNING "%s: Failed to request resource"
1619 				       ", port still active\n",
1620 				       uap->node->name);
1621 			else
1622 				uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
1623 			return 0;
1624 		}
1625 	return -ENODEV;
1626 }
1627 
1628 /*
1629  * That one should not be called, macio isn't really a hotswap device,
1630  * we don't expect one of those serial ports to go away...
1631  */
1632 static int pmz_detach(struct macio_dev *mdev)
1633 {
1634 	struct uart_pmac_port	*uap = dev_get_drvdata(&mdev->ofdev.dev);
1635 
1636 	if (!uap)
1637 		return -ENODEV;
1638 
1639 	if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
1640 		macio_release_resources(uap->dev);
1641 		uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
1642 	}
1643 	dev_set_drvdata(&mdev->ofdev.dev, NULL);
1644 	uap->dev = NULL;
1645 
1646 	return 0;
1647 }
1648 
1649 
1650 static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
1651 {
1652 	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1653 	struct uart_state *state;
1654 	unsigned long flags;
1655 
1656 	if (uap == NULL) {
1657 		printk("HRM... pmz_suspend with NULL uap\n");
1658 		return 0;
1659 	}
1660 
1661 	if (pm_state.event == mdev->ofdev.dev.power.power_state.event)
1662 		return 0;
1663 
1664 	pmz_debug("suspend, switching to state %d\n", pm_state.event);
1665 
1666 	state = pmz_uart_reg.state + uap->port.line;
1667 
1668 	mutex_lock(&pmz_irq_mutex);
1669 	mutex_lock(&state->port.mutex);
1670 
1671 	spin_lock_irqsave(&uap->port.lock, flags);
1672 
1673 	if (ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)) {
1674 		/* Disable receiver and transmitter.  */
1675 		uap->curregs[R3] &= ~RxENABLE;
1676 		uap->curregs[R5] &= ~TxENABLE;
1677 
1678 		/* Disable all interrupts and BRK assertion.  */
1679 		uap->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
1680 		uap->curregs[R5] &= ~SND_BRK;
1681 		pmz_load_zsregs(uap, uap->curregs);
1682 		uap->flags |= PMACZILOG_FLAG_IS_ASLEEP;
1683 		mb();
1684 	}
1685 
1686 	spin_unlock_irqrestore(&uap->port.lock, flags);
1687 
1688 	if (ZS_IS_OPEN(uap) || ZS_IS_OPEN(uap->mate))
1689 		if (ZS_IS_ASLEEP(uap->mate) && ZS_IS_IRQ_ON(pmz_get_port_A(uap))) {
1690 			pmz_get_port_A(uap)->flags &= ~PMACZILOG_FLAG_IS_IRQ_ON;
1691 			disable_irq(uap->port.irq);
1692 		}
1693 
1694 	if (ZS_IS_CONS(uap))
1695 		uap->port.cons->flags &= ~CON_ENABLED;
1696 
1697 	/* Shut the chip down */
1698 	pmz_set_scc_power(uap, 0);
1699 
1700 	mutex_unlock(&state->port.mutex);
1701 	mutex_unlock(&pmz_irq_mutex);
1702 
1703 	pmz_debug("suspend, switching complete\n");
1704 
1705 	mdev->ofdev.dev.power.power_state = pm_state;
1706 
1707 	return 0;
1708 }
1709 
1710 
1711 static int pmz_resume(struct macio_dev *mdev)
1712 {
1713 	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1714 	struct uart_state *state;
1715 	unsigned long flags;
1716 	int pwr_delay = 0;
1717 
1718 	if (uap == NULL)
1719 		return 0;
1720 
1721 	if (mdev->ofdev.dev.power.power_state.event == PM_EVENT_ON)
1722 		return 0;
1723 
1724 	pmz_debug("resume, switching to state 0\n");
1725 
1726 	state = pmz_uart_reg.state + uap->port.line;
1727 
1728 	mutex_lock(&pmz_irq_mutex);
1729 	mutex_lock(&state->port.mutex);
1730 
1731 	spin_lock_irqsave(&uap->port.lock, flags);
1732 	if (!ZS_IS_OPEN(uap) && !ZS_IS_CONS(uap)) {
1733 		spin_unlock_irqrestore(&uap->port.lock, flags);
1734 		goto bail;
1735 	}
1736 	pwr_delay = __pmz_startup(uap);
1737 
1738 	/* Take care of config that may have changed while asleep */
1739 	__pmz_set_termios(&uap->port, &uap->termios_cache, NULL);
1740 
1741 	if (ZS_IS_OPEN(uap)) {
1742 		/* Enable interrupts */
1743 		uap->curregs[R1] |= INT_ALL_Rx | TxINT_ENAB;
1744 		if (!ZS_IS_EXTCLK(uap))
1745 			uap->curregs[R1] |= EXT_INT_ENAB;
1746 		write_zsreg(uap, R1, uap->curregs[R1]);
1747 	}
1748 
1749 	spin_unlock_irqrestore(&uap->port.lock, flags);
1750 
1751 	if (ZS_IS_CONS(uap))
1752 		uap->port.cons->flags |= CON_ENABLED;
1753 
1754 	/* Re-enable IRQ on the controller */
1755 	if (ZS_IS_OPEN(uap) && !ZS_IS_IRQ_ON(pmz_get_port_A(uap))) {
1756 		pmz_get_port_A(uap)->flags |= PMACZILOG_FLAG_IS_IRQ_ON;
1757 		enable_irq(uap->port.irq);
1758 	}
1759 
1760  bail:
1761 	mutex_unlock(&state->port.mutex);
1762 	mutex_unlock(&pmz_irq_mutex);
1763 
1764 	/* Right now, we deal with delay by blocking here, I'll be
1765 	 * smarter later on
1766 	 */
1767 	if (pwr_delay != 0) {
1768 		pmz_debug("pmz: delaying %d ms\n", pwr_delay);
1769 		msleep(pwr_delay);
1770 	}
1771 
1772 	pmz_debug("resume, switching complete\n");
1773 
1774 	mdev->ofdev.dev.power.power_state.event = PM_EVENT_ON;
1775 
1776 	return 0;
1777 }
1778 
1779 /*
1780  * Probe all ports in the system and build the ports array, we register
1781  * with the serial layer at this point, the macio-type probing is only
1782  * used later to "attach" to the sysfs tree so we get power management
1783  * events
1784  */
1785 static int __init pmz_probe(void)
1786 {
1787 	struct device_node	*node_p, *node_a, *node_b, *np;
1788 	int			count = 0;
1789 	int			rc;
1790 
1791 	/*
1792 	 * Find all escc chips in the system
1793 	 */
1794 	node_p = of_find_node_by_name(NULL, "escc");
1795 	while (node_p) {
1796 		/*
1797 		 * First get channel A/B node pointers
1798 		 *
1799 		 * TODO: Add routines with proper locking to do that...
1800 		 */
1801 		node_a = node_b = NULL;
1802 		for (np = NULL; (np = of_get_next_child(node_p, np)) != NULL;) {
1803 			if (strncmp(np->name, "ch-a", 4) == 0)
1804 				node_a = of_node_get(np);
1805 			else if (strncmp(np->name, "ch-b", 4) == 0)
1806 				node_b = of_node_get(np);
1807 		}
1808 		if (!node_a && !node_b) {
1809 			of_node_put(node_a);
1810 			of_node_put(node_b);
1811 			printk(KERN_ERR "pmac_zilog: missing node %c for escc %s\n",
1812 				(!node_a) ? 'a' : 'b', node_p->full_name);
1813 			goto next;
1814 		}
1815 
1816 		/*
1817 		 * Fill basic fields in the port structures
1818 		 */
1819 		pmz_ports[count].mate		= &pmz_ports[count+1];
1820 		pmz_ports[count+1].mate		= &pmz_ports[count];
1821 		pmz_ports[count].flags		= PMACZILOG_FLAG_IS_CHANNEL_A;
1822 		pmz_ports[count].node		= node_a;
1823 		pmz_ports[count+1].node		= node_b;
1824 		pmz_ports[count].port.line	= count;
1825 		pmz_ports[count+1].port.line	= count+1;
1826 
1827 		/*
1828 		 * Setup the ports for real
1829 		 */
1830 		rc = pmz_init_port(&pmz_ports[count]);
1831 		if (rc == 0 && node_b != NULL)
1832 			rc = pmz_init_port(&pmz_ports[count+1]);
1833 		if (rc != 0) {
1834 			of_node_put(node_a);
1835 			of_node_put(node_b);
1836 			memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
1837 			memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
1838 			goto next;
1839 		}
1840 		count += 2;
1841 next:
1842 		node_p = of_find_node_by_name(node_p, "escc");
1843 	}
1844 	pmz_ports_count = count;
1845 
1846 	return 0;
1847 }
1848 
1849 #else
1850 
1851 extern struct platform_device scc_a_pdev, scc_b_pdev;
1852 
1853 static int __init pmz_init_port(struct uart_pmac_port *uap)
1854 {
1855 	struct resource *r_ports;
1856 	int irq;
1857 
1858 	r_ports = platform_get_resource(uap->node, IORESOURCE_MEM, 0);
1859 	irq = platform_get_irq(uap->node, 0);
1860 	if (!r_ports || !irq)
1861 		return -ENODEV;
1862 
1863 	uap->port.mapbase  = r_ports->start;
1864 	uap->port.membase  = (unsigned char __iomem *) r_ports->start;
1865 	uap->port.iotype   = UPIO_MEM;
1866 	uap->port.irq      = irq;
1867 	uap->port.uartclk  = ZS_CLOCK;
1868 	uap->port.fifosize = 1;
1869 	uap->port.ops      = &pmz_pops;
1870 	uap->port.type     = PORT_PMAC_ZILOG;
1871 	uap->port.flags    = 0;
1872 
1873 	uap->control_reg   = uap->port.membase;
1874 	uap->data_reg      = uap->control_reg + 4;
1875 	uap->port_type     = 0;
1876 
1877 	pmz_convert_to_zs(uap, CS8, 0, 9600);
1878 
1879 	return 0;
1880 }
1881 
1882 static int __init pmz_probe(void)
1883 {
1884 	int err;
1885 
1886 	pmz_ports_count = 0;
1887 
1888 	pmz_ports[0].mate      = &pmz_ports[1];
1889 	pmz_ports[0].port.line = 0;
1890 	pmz_ports[0].flags     = PMACZILOG_FLAG_IS_CHANNEL_A;
1891 	pmz_ports[0].node      = &scc_a_pdev;
1892 	err = pmz_init_port(&pmz_ports[0]);
1893 	if (err)
1894 		return err;
1895 	pmz_ports_count++;
1896 
1897 	pmz_ports[1].mate      = &pmz_ports[0];
1898 	pmz_ports[1].port.line = 1;
1899 	pmz_ports[1].flags     = 0;
1900 	pmz_ports[1].node      = &scc_b_pdev;
1901 	err = pmz_init_port(&pmz_ports[1]);
1902 	if (err)
1903 		return err;
1904 	pmz_ports_count++;
1905 
1906 	return 0;
1907 }
1908 
1909 static void pmz_dispose_port(struct uart_pmac_port *uap)
1910 {
1911 	memset(uap, 0, sizeof(struct uart_pmac_port));
1912 }
1913 
1914 static int __init pmz_attach(struct platform_device *pdev)
1915 {
1916 	int i;
1917 
1918 	for (i = 0; i < pmz_ports_count; i++)
1919 		if (pmz_ports[i].node == pdev)
1920 			return 0;
1921 	return -ENODEV;
1922 }
1923 
1924 static int __exit pmz_detach(struct platform_device *pdev)
1925 {
1926 	return 0;
1927 }
1928 
1929 #endif /* !CONFIG_PPC_PMAC */
1930 
1931 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1932 
1933 static void pmz_console_write(struct console *con, const char *s, unsigned int count);
1934 static int __init pmz_console_setup(struct console *co, char *options);
1935 
1936 static struct console pmz_console = {
1937 	.name	=	PMACZILOG_NAME,
1938 	.write	=	pmz_console_write,
1939 	.device	=	uart_console_device,
1940 	.setup	=	pmz_console_setup,
1941 	.flags	=	CON_PRINTBUFFER,
1942 	.index	=	-1,
1943 	.data   =	&pmz_uart_reg,
1944 };
1945 
1946 #define PMACZILOG_CONSOLE	&pmz_console
1947 #else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1948 #define PMACZILOG_CONSOLE	(NULL)
1949 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1950 
1951 /*
1952  * Register the driver, console driver and ports with the serial
1953  * core
1954  */
1955 static int __init pmz_register(void)
1956 {
1957 	int i, rc;
1958 
1959 	pmz_uart_reg.nr = pmz_ports_count;
1960 	pmz_uart_reg.cons = PMACZILOG_CONSOLE;
1961 
1962 	/*
1963 	 * Register this driver with the serial core
1964 	 */
1965 	rc = uart_register_driver(&pmz_uart_reg);
1966 	if (rc)
1967 		return rc;
1968 
1969 	/*
1970 	 * Register each port with the serial core
1971 	 */
1972 	for (i = 0; i < pmz_ports_count; i++) {
1973 		struct uart_pmac_port *uport = &pmz_ports[i];
1974 		/* NULL node may happen on wallstreet */
1975 		if (uport->node != NULL)
1976 			rc = uart_add_one_port(&pmz_uart_reg, &uport->port);
1977 		if (rc)
1978 			goto err_out;
1979 	}
1980 
1981 	return 0;
1982 err_out:
1983 	while (i-- > 0) {
1984 		struct uart_pmac_port *uport = &pmz_ports[i];
1985 		uart_remove_one_port(&pmz_uart_reg, &uport->port);
1986 	}
1987 	uart_unregister_driver(&pmz_uart_reg);
1988 	return rc;
1989 }
1990 
1991 #ifdef CONFIG_PPC_PMAC
1992 
1993 static struct of_device_id pmz_match[] =
1994 {
1995 	{
1996 	.name		= "ch-a",
1997 	},
1998 	{
1999 	.name		= "ch-b",
2000 	},
2001 	{},
2002 };
2003 MODULE_DEVICE_TABLE (of, pmz_match);
2004 
2005 static struct macio_driver pmz_driver = {
2006 	.driver = {
2007 		.name 		= "pmac_zilog",
2008 		.owner		= THIS_MODULE,
2009 		.of_match_table	= pmz_match,
2010 	},
2011 	.probe		= pmz_attach,
2012 	.remove		= pmz_detach,
2013 	.suspend	= pmz_suspend,
2014 	.resume		= pmz_resume,
2015 };
2016 
2017 #else
2018 
2019 static struct platform_driver pmz_driver = {
2020 	.remove		= __exit_p(pmz_detach),
2021 	.driver		= {
2022 		.name		= "scc",
2023 		.owner		= THIS_MODULE,
2024 	},
2025 };
2026 
2027 #endif /* !CONFIG_PPC_PMAC */
2028 
2029 static int __init init_pmz(void)
2030 {
2031 	int rc, i;
2032 	printk(KERN_INFO "%s\n", version);
2033 
2034 	/*
2035 	 * First, we need to do a direct OF-based probe pass. We
2036 	 * do that because we want serial console up before the
2037 	 * macio stuffs calls us back, and since that makes it
2038 	 * easier to pass the proper number of channels to
2039 	 * uart_register_driver()
2040 	 */
2041 	if (pmz_ports_count == 0)
2042 		pmz_probe();
2043 
2044 	/*
2045 	 * Bail early if no port found
2046 	 */
2047 	if (pmz_ports_count == 0)
2048 		return -ENODEV;
2049 
2050 	/*
2051 	 * Now we register with the serial layer
2052 	 */
2053 	rc = pmz_register();
2054 	if (rc) {
2055 		printk(KERN_ERR
2056 			"pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"
2057 		 	"pmac_zilog: Did another serial driver already claim the minors?\n");
2058 		/* effectively "pmz_unprobe()" */
2059 		for (i=0; i < pmz_ports_count; i++)
2060 			pmz_dispose_port(&pmz_ports[i]);
2061 		return rc;
2062 	}
2063 
2064 	/*
2065 	 * Then we register the macio driver itself
2066 	 */
2067 #ifdef CONFIG_PPC_PMAC
2068 	return macio_register_driver(&pmz_driver);
2069 #else
2070 	return platform_driver_probe(&pmz_driver, pmz_attach);
2071 #endif
2072 }
2073 
2074 static void __exit exit_pmz(void)
2075 {
2076 	int i;
2077 
2078 #ifdef CONFIG_PPC_PMAC
2079 	/* Get rid of macio-driver (detach from macio) */
2080 	macio_unregister_driver(&pmz_driver);
2081 #else
2082 	platform_driver_unregister(&pmz_driver);
2083 #endif
2084 
2085 	for (i = 0; i < pmz_ports_count; i++) {
2086 		struct uart_pmac_port *uport = &pmz_ports[i];
2087 		if (uport->node != NULL) {
2088 			uart_remove_one_port(&pmz_uart_reg, &uport->port);
2089 			pmz_dispose_port(uport);
2090 		}
2091 	}
2092 	/* Unregister UART driver */
2093 	uart_unregister_driver(&pmz_uart_reg);
2094 }
2095 
2096 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
2097 
2098 static void pmz_console_putchar(struct uart_port *port, int ch)
2099 {
2100 	struct uart_pmac_port *uap = (struct uart_pmac_port *)port;
2101 
2102 	/* Wait for the transmit buffer to empty. */
2103 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
2104 		udelay(5);
2105 	write_zsdata(uap, ch);
2106 }
2107 
2108 /*
2109  * Print a string to the serial port trying not to disturb
2110  * any possible real use of the port...
2111  */
2112 static void pmz_console_write(struct console *con, const char *s, unsigned int count)
2113 {
2114 	struct uart_pmac_port *uap = &pmz_ports[con->index];
2115 	unsigned long flags;
2116 
2117 	if (ZS_IS_ASLEEP(uap))
2118 		return;
2119 	spin_lock_irqsave(&uap->port.lock, flags);
2120 
2121 	/* Turn of interrupts and enable the transmitter. */
2122 	write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);
2123 	write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);
2124 
2125 	uart_console_write(&uap->port, s, count, pmz_console_putchar);
2126 
2127 	/* Restore the values in the registers. */
2128 	write_zsreg(uap, R1, uap->curregs[1]);
2129 	/* Don't disable the transmitter. */
2130 
2131 	spin_unlock_irqrestore(&uap->port.lock, flags);
2132 }
2133 
2134 /*
2135  * Setup the serial console
2136  */
2137 static int __init pmz_console_setup(struct console *co, char *options)
2138 {
2139 	struct uart_pmac_port *uap;
2140 	struct uart_port *port;
2141 	int baud = 38400;
2142 	int bits = 8;
2143 	int parity = 'n';
2144 	int flow = 'n';
2145 	unsigned long pwr_delay;
2146 
2147 	/*
2148 	 * XServe's default to 57600 bps
2149 	 */
2150 	if (of_machine_is_compatible("RackMac1,1")
2151 	    || of_machine_is_compatible("RackMac1,2")
2152 	    || of_machine_is_compatible("MacRISC4"))
2153 		baud = 57600;
2154 
2155 	/*
2156 	 * Check whether an invalid uart number has been specified, and
2157 	 * if so, search for the first available port that does have
2158 	 * console support.
2159 	 */
2160 	if (co->index >= pmz_ports_count)
2161 		co->index = 0;
2162 	uap = &pmz_ports[co->index];
2163 	if (uap->node == NULL)
2164 		return -ENODEV;
2165 	port = &uap->port;
2166 
2167 	/*
2168 	 * Mark port as beeing a console
2169 	 */
2170 	uap->flags |= PMACZILOG_FLAG_IS_CONS;
2171 
2172 	/*
2173 	 * Temporary fix for uart layer who didn't setup the spinlock yet
2174 	 */
2175 	spin_lock_init(&port->lock);
2176 
2177 	/*
2178 	 * Enable the hardware
2179 	 */
2180 	pwr_delay = __pmz_startup(uap);
2181 	if (pwr_delay)
2182 		mdelay(pwr_delay);
2183 
2184 	if (options)
2185 		uart_parse_options(options, &baud, &parity, &bits, &flow);
2186 
2187 	return uart_set_options(port, co, baud, parity, bits, flow);
2188 }
2189 
2190 static int __init pmz_console_init(void)
2191 {
2192 	/* Probe ports */
2193 	pmz_probe();
2194 
2195 	/* TODO: Autoprobe console based on OF */
2196 	/* pmz_console.index = i; */
2197 	register_console(&pmz_console);
2198 
2199 	return 0;
2200 
2201 }
2202 console_initcall(pmz_console_init);
2203 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
2204 
2205 module_init(init_pmz);
2206 module_exit(exit_pmz);
2207