xref: /openbmc/linux/drivers/tty/serial/pmac_zilog.c (revision 6c33a6f4)
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 DEBUG_HARD
28 #undef USE_CTRL_O_SYSRQ
29 
30 #include <linux/module.h>
31 #include <linux/tty.h>
32 
33 #include <linux/tty_flip.h>
34 #include <linux/major.h>
35 #include <linux/string.h>
36 #include <linux/fcntl.h>
37 #include <linux/mm.h>
38 #include <linux/kernel.h>
39 #include <linux/delay.h>
40 #include <linux/init.h>
41 #include <linux/console.h>
42 #include <linux/adb.h>
43 #include <linux/pmu.h>
44 #include <linux/bitops.h>
45 #include <linux/sysrq.h>
46 #include <linux/mutex.h>
47 #include <linux/of_address.h>
48 #include <linux/of_irq.h>
49 #include <asm/sections.h>
50 #include <asm/io.h>
51 #include <asm/irq.h>
52 
53 #ifdef CONFIG_PPC_PMAC
54 #include <asm/prom.h>
55 #include <asm/machdep.h>
56 #include <asm/pmac_feature.h>
57 #include <asm/dbdma.h>
58 #include <asm/macio.h>
59 #else
60 #include <linux/platform_device.h>
61 #define of_machine_is_compatible(x) (0)
62 #endif
63 
64 #include <linux/serial.h>
65 #include <linux/serial_core.h>
66 
67 #include "pmac_zilog.h"
68 
69 /* Not yet implemented */
70 #undef HAS_DBDMA
71 
72 static char version[] __initdata = "pmac_zilog: 0.6 (Benjamin Herrenschmidt <benh@kernel.crashing.org>)";
73 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
74 MODULE_DESCRIPTION("Driver for the Mac and PowerMac serial ports.");
75 MODULE_LICENSE("GPL");
76 
77 #ifdef CONFIG_SERIAL_PMACZILOG_TTYS
78 #define PMACZILOG_MAJOR		TTY_MAJOR
79 #define PMACZILOG_MINOR		64
80 #define PMACZILOG_NAME		"ttyS"
81 #else
82 #define PMACZILOG_MAJOR		204
83 #define PMACZILOG_MINOR		192
84 #define PMACZILOG_NAME		"ttyPZ"
85 #endif
86 
87 #define pmz_debug(fmt, arg...)	pr_debug("ttyPZ%d: " fmt, uap->port.line, ## arg)
88 #define pmz_error(fmt, arg...)	pr_err("ttyPZ%d: " fmt, uap->port.line, ## arg)
89 #define pmz_info(fmt, arg...)	pr_info("ttyPZ%d: " fmt, uap->port.line, ## arg)
90 
91 /*
92  * For the sake of early serial console, we can do a pre-probe
93  * (optional) of the ports at rather early boot time.
94  */
95 static struct uart_pmac_port	pmz_ports[MAX_ZS_PORTS];
96 static int			pmz_ports_count;
97 
98 static struct uart_driver pmz_uart_reg = {
99 	.owner		=	THIS_MODULE,
100 	.driver_name	=	PMACZILOG_NAME,
101 	.dev_name	=	PMACZILOG_NAME,
102 	.major		=	PMACZILOG_MAJOR,
103 	.minor		=	PMACZILOG_MINOR,
104 };
105 
106 
107 /*
108  * Load all registers to reprogram the port
109  * This function must only be called when the TX is not busy.  The UART
110  * port lock must be held and local interrupts disabled.
111  */
112 static void pmz_load_zsregs(struct uart_pmac_port *uap, u8 *regs)
113 {
114 	int i;
115 
116 	/* Let pending transmits finish.  */
117 	for (i = 0; i < 1000; i++) {
118 		unsigned char stat = read_zsreg(uap, R1);
119 		if (stat & ALL_SNT)
120 			break;
121 		udelay(100);
122 	}
123 
124 	ZS_CLEARERR(uap);
125 	zssync(uap);
126 	ZS_CLEARFIFO(uap);
127 	zssync(uap);
128 	ZS_CLEARERR(uap);
129 
130 	/* Disable all interrupts.  */
131 	write_zsreg(uap, R1,
132 		    regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
133 
134 	/* Set parity, sync config, stop bits, and clock divisor.  */
135 	write_zsreg(uap, R4, regs[R4]);
136 
137 	/* Set misc. TX/RX control bits.  */
138 	write_zsreg(uap, R10, regs[R10]);
139 
140 	/* Set TX/RX controls sans the enable bits.  */
141 	write_zsreg(uap, R3, regs[R3] & ~RxENABLE);
142 	write_zsreg(uap, R5, regs[R5] & ~TxENABLE);
143 
144 	/* now set R7 "prime" on ESCC */
145 	write_zsreg(uap, R15, regs[R15] | EN85C30);
146 	write_zsreg(uap, R7, regs[R7P]);
147 
148 	/* make sure we use R7 "non-prime" on ESCC */
149 	write_zsreg(uap, R15, regs[R15] & ~EN85C30);
150 
151 	/* Synchronous mode config.  */
152 	write_zsreg(uap, R6, regs[R6]);
153 	write_zsreg(uap, R7, regs[R7]);
154 
155 	/* Disable baud generator.  */
156 	write_zsreg(uap, R14, regs[R14] & ~BRENAB);
157 
158 	/* Clock mode control.  */
159 	write_zsreg(uap, R11, regs[R11]);
160 
161 	/* Lower and upper byte of baud rate generator divisor.  */
162 	write_zsreg(uap, R12, regs[R12]);
163 	write_zsreg(uap, R13, regs[R13]);
164 
165 	/* Now rewrite R14, with BRENAB (if set).  */
166 	write_zsreg(uap, R14, regs[R14]);
167 
168 	/* Reset external status interrupts.  */
169 	write_zsreg(uap, R0, RES_EXT_INT);
170 	write_zsreg(uap, R0, RES_EXT_INT);
171 
172 	/* Rewrite R3/R5, this time without enables masked.  */
173 	write_zsreg(uap, R3, regs[R3]);
174 	write_zsreg(uap, R5, regs[R5]);
175 
176 	/* Rewrite R1, this time without IRQ enabled masked.  */
177 	write_zsreg(uap, R1, regs[R1]);
178 
179 	/* Enable interrupts */
180 	write_zsreg(uap, R9, regs[R9]);
181 }
182 
183 /*
184  * We do like sunzilog to avoid disrupting pending Tx
185  * Reprogram the Zilog channel HW registers with the copies found in the
186  * software state struct.  If the transmitter is busy, we defer this update
187  * until the next TX complete interrupt.  Else, we do it right now.
188  *
189  * The UART port lock must be held and local interrupts disabled.
190  */
191 static void pmz_maybe_update_regs(struct uart_pmac_port *uap)
192 {
193 	if (!ZS_REGS_HELD(uap)) {
194 		if (ZS_TX_ACTIVE(uap)) {
195 			uap->flags |= PMACZILOG_FLAG_REGS_HELD;
196 		} else {
197 			pmz_debug("pmz: maybe_update_regs: updating\n");
198 			pmz_load_zsregs(uap, uap->curregs);
199 		}
200 	}
201 }
202 
203 static void pmz_interrupt_control(struct uart_pmac_port *uap, int enable)
204 {
205 	if (enable) {
206 		uap->curregs[1] |= INT_ALL_Rx | TxINT_ENAB;
207 		if (!ZS_IS_EXTCLK(uap))
208 			uap->curregs[1] |= EXT_INT_ENAB;
209 	} else {
210 		uap->curregs[1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
211 	}
212 	write_zsreg(uap, R1, uap->curregs[1]);
213 }
214 
215 static bool pmz_receive_chars(struct uart_pmac_port *uap)
216 {
217 	struct tty_port *port;
218 	unsigned char ch, r1, drop, flag;
219 	int loops = 0;
220 
221 	/* Sanity check, make sure the old bug is no longer happening */
222 	if (uap->port.state == NULL) {
223 		WARN_ON(1);
224 		(void)read_zsdata(uap);
225 		return false;
226 	}
227 	port = &uap->port.state->port;
228 
229 	while (1) {
230 		drop = 0;
231 
232 		r1 = read_zsreg(uap, R1);
233 		ch = read_zsdata(uap);
234 
235 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
236 			write_zsreg(uap, R0, ERR_RES);
237 			zssync(uap);
238 		}
239 
240 		ch &= uap->parity_mask;
241 		if (ch == 0 && uap->flags & PMACZILOG_FLAG_BREAK) {
242 			uap->flags &= ~PMACZILOG_FLAG_BREAK;
243 		}
244 
245 #if defined(CONFIG_MAGIC_SYSRQ) && defined(CONFIG_SERIAL_CORE_CONSOLE)
246 #ifdef USE_CTRL_O_SYSRQ
247 		/* Handle the SysRq ^O Hack */
248 		if (ch == '\x0f') {
249 			uap->port.sysrq = jiffies + HZ*5;
250 			goto next_char;
251 		}
252 #endif /* USE_CTRL_O_SYSRQ */
253 		if (uap->port.sysrq) {
254 			int swallow;
255 			spin_unlock(&uap->port.lock);
256 			swallow = uart_handle_sysrq_char(&uap->port, ch);
257 			spin_lock(&uap->port.lock);
258 			if (swallow)
259 				goto next_char;
260 		}
261 #endif /* CONFIG_MAGIC_SYSRQ && CONFIG_SERIAL_CORE_CONSOLE */
262 
263 		/* A real serial line, record the character and status.  */
264 		if (drop)
265 			goto next_char;
266 
267 		flag = TTY_NORMAL;
268 		uap->port.icount.rx++;
269 
270 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR | BRK_ABRT)) {
271 			if (r1 & BRK_ABRT) {
272 				pmz_debug("pmz: got break !\n");
273 				r1 &= ~(PAR_ERR | CRC_ERR);
274 				uap->port.icount.brk++;
275 				if (uart_handle_break(&uap->port))
276 					goto next_char;
277 			}
278 			else if (r1 & PAR_ERR)
279 				uap->port.icount.parity++;
280 			else if (r1 & CRC_ERR)
281 				uap->port.icount.frame++;
282 			if (r1 & Rx_OVR)
283 				uap->port.icount.overrun++;
284 			r1 &= uap->port.read_status_mask;
285 			if (r1 & BRK_ABRT)
286 				flag = TTY_BREAK;
287 			else if (r1 & PAR_ERR)
288 				flag = TTY_PARITY;
289 			else if (r1 & CRC_ERR)
290 				flag = TTY_FRAME;
291 		}
292 
293 		if (uap->port.ignore_status_mask == 0xff ||
294 		    (r1 & uap->port.ignore_status_mask) == 0) {
295 			tty_insert_flip_char(port, ch, flag);
296 		}
297 		if (r1 & Rx_OVR)
298 			tty_insert_flip_char(port, 0, TTY_OVERRUN);
299 	next_char:
300 		/* We can get stuck in an infinite loop getting char 0 when the
301 		 * line is in a wrong HW state, we break that here.
302 		 * When that happens, I disable the receive side of the driver.
303 		 * Note that what I've been experiencing is a real irq loop where
304 		 * I'm getting flooded regardless of the actual port speed.
305 		 * Something strange is going on with the HW
306 		 */
307 		if ((++loops) > 1000)
308 			goto flood;
309 		ch = read_zsreg(uap, R0);
310 		if (!(ch & Rx_CH_AV))
311 			break;
312 	}
313 
314 	return true;
315  flood:
316 	pmz_interrupt_control(uap, 0);
317 	pmz_error("pmz: rx irq flood !\n");
318 	return true;
319 }
320 
321 static void pmz_status_handle(struct uart_pmac_port *uap)
322 {
323 	unsigned char status;
324 
325 	status = read_zsreg(uap, R0);
326 	write_zsreg(uap, R0, RES_EXT_INT);
327 	zssync(uap);
328 
329 	if (ZS_IS_OPEN(uap) && ZS_WANTS_MODEM_STATUS(uap)) {
330 		if (status & SYNC_HUNT)
331 			uap->port.icount.dsr++;
332 
333 		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
334 		 * But it does not tell us which bit has changed, we have to keep
335 		 * track of this ourselves.
336 		 * The CTS input is inverted for some reason.  -- paulus
337 		 */
338 		if ((status ^ uap->prev_status) & DCD)
339 			uart_handle_dcd_change(&uap->port,
340 					       (status & DCD));
341 		if ((status ^ uap->prev_status) & CTS)
342 			uart_handle_cts_change(&uap->port,
343 					       !(status & CTS));
344 
345 		wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
346 	}
347 
348 	if (status & BRK_ABRT)
349 		uap->flags |= PMACZILOG_FLAG_BREAK;
350 
351 	uap->prev_status = status;
352 }
353 
354 static void pmz_transmit_chars(struct uart_pmac_port *uap)
355 {
356 	struct circ_buf *xmit;
357 
358 	if (ZS_IS_CONS(uap)) {
359 		unsigned char status = read_zsreg(uap, R0);
360 
361 		/* TX still busy?  Just wait for the next TX done interrupt.
362 		 *
363 		 * It can occur because of how we do serial console writes.  It would
364 		 * be nice to transmit console writes just like we normally would for
365 		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not
366 		 * easy because console writes cannot sleep.  One solution might be
367 		 * to poll on enough port->xmit space becoming free.  -DaveM
368 		 */
369 		if (!(status & Tx_BUF_EMP))
370 			return;
371 	}
372 
373 	uap->flags &= ~PMACZILOG_FLAG_TX_ACTIVE;
374 
375 	if (ZS_REGS_HELD(uap)) {
376 		pmz_load_zsregs(uap, uap->curregs);
377 		uap->flags &= ~PMACZILOG_FLAG_REGS_HELD;
378 	}
379 
380 	if (ZS_TX_STOPPED(uap)) {
381 		uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
382 		goto ack_tx_int;
383 	}
384 
385 	/* Under some circumstances, we see interrupts reported for
386 	 * a closed channel. The interrupt mask in R1 is clear, but
387 	 * R3 still signals the interrupts and we see them when taking
388 	 * an interrupt for the other channel (this could be a qemu
389 	 * bug but since the ESCC doc doesn't specify precsiely whether
390 	 * R3 interrup status bits are masked by R1 interrupt enable
391 	 * bits, better safe than sorry). --BenH.
392 	 */
393 	if (!ZS_IS_OPEN(uap))
394 		goto ack_tx_int;
395 
396 	if (uap->port.x_char) {
397 		uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
398 		write_zsdata(uap, uap->port.x_char);
399 		zssync(uap);
400 		uap->port.icount.tx++;
401 		uap->port.x_char = 0;
402 		return;
403 	}
404 
405 	if (uap->port.state == NULL)
406 		goto ack_tx_int;
407 	xmit = &uap->port.state->xmit;
408 	if (uart_circ_empty(xmit)) {
409 		uart_write_wakeup(&uap->port);
410 		goto ack_tx_int;
411 	}
412 	if (uart_tx_stopped(&uap->port))
413 		goto ack_tx_int;
414 
415 	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
416 	write_zsdata(uap, xmit->buf[xmit->tail]);
417 	zssync(uap);
418 
419 	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
420 	uap->port.icount.tx++;
421 
422 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
423 		uart_write_wakeup(&uap->port);
424 
425 	return;
426 
427 ack_tx_int:
428 	write_zsreg(uap, R0, RES_Tx_P);
429 	zssync(uap);
430 }
431 
432 /* Hrm... we register that twice, fixme later.... */
433 static irqreturn_t pmz_interrupt(int irq, void *dev_id)
434 {
435 	struct uart_pmac_port *uap = dev_id;
436 	struct uart_pmac_port *uap_a;
437 	struct uart_pmac_port *uap_b;
438 	int rc = IRQ_NONE;
439 	bool push;
440 	u8 r3;
441 
442 	uap_a = pmz_get_port_A(uap);
443 	uap_b = uap_a->mate;
444 
445 	spin_lock(&uap_a->port.lock);
446 	r3 = read_zsreg(uap_a, R3);
447 
448 #ifdef DEBUG_HARD
449 	pmz_debug("irq, r3: %x\n", r3);
450 #endif
451 	/* Channel A */
452 	push = false;
453 	if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
454 		if (!ZS_IS_OPEN(uap_a)) {
455 			pmz_debug("ChanA interrupt while not open !\n");
456 			goto skip_a;
457 		}
458 		write_zsreg(uap_a, R0, RES_H_IUS);
459 		zssync(uap_a);
460 		if (r3 & CHAEXT)
461 			pmz_status_handle(uap_a);
462 		if (r3 & CHARxIP)
463 			push = pmz_receive_chars(uap_a);
464 		if (r3 & CHATxIP)
465 			pmz_transmit_chars(uap_a);
466 		rc = IRQ_HANDLED;
467 	}
468  skip_a:
469 	spin_unlock(&uap_a->port.lock);
470 	if (push)
471 		tty_flip_buffer_push(&uap->port.state->port);
472 
473 	if (!uap_b)
474 		goto out;
475 
476 	spin_lock(&uap_b->port.lock);
477 	push = false;
478 	if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
479 		if (!ZS_IS_OPEN(uap_b)) {
480 			pmz_debug("ChanB interrupt while not open !\n");
481 			goto skip_b;
482 		}
483 		write_zsreg(uap_b, R0, RES_H_IUS);
484 		zssync(uap_b);
485 		if (r3 & CHBEXT)
486 			pmz_status_handle(uap_b);
487 		if (r3 & CHBRxIP)
488 			push = pmz_receive_chars(uap_b);
489 		if (r3 & CHBTxIP)
490 			pmz_transmit_chars(uap_b);
491 		rc = IRQ_HANDLED;
492 	}
493  skip_b:
494 	spin_unlock(&uap_b->port.lock);
495 	if (push)
496 		tty_flip_buffer_push(&uap->port.state->port);
497 
498  out:
499 	return rc;
500 }
501 
502 /*
503  * Peek the status register, lock not held by caller
504  */
505 static inline u8 pmz_peek_status(struct uart_pmac_port *uap)
506 {
507 	unsigned long flags;
508 	u8 status;
509 
510 	spin_lock_irqsave(&uap->port.lock, flags);
511 	status = read_zsreg(uap, R0);
512 	spin_unlock_irqrestore(&uap->port.lock, flags);
513 
514 	return status;
515 }
516 
517 /*
518  * Check if transmitter is empty
519  * The port lock is not held.
520  */
521 static unsigned int pmz_tx_empty(struct uart_port *port)
522 {
523 	unsigned char status;
524 
525 	status = pmz_peek_status(to_pmz(port));
526 	if (status & Tx_BUF_EMP)
527 		return TIOCSER_TEMT;
528 	return 0;
529 }
530 
531 /*
532  * Set Modem Control (RTS & DTR) bits
533  * The port lock is held and interrupts are disabled.
534  * Note: Shall we really filter out RTS on external ports or
535  * should that be dealt at higher level only ?
536  */
537 static void pmz_set_mctrl(struct uart_port *port, unsigned int mctrl)
538 {
539 	struct uart_pmac_port *uap = to_pmz(port);
540 	unsigned char set_bits, clear_bits;
541 
542         /* Do nothing for irda for now... */
543 	if (ZS_IS_IRDA(uap))
544 		return;
545 	/* We get called during boot with a port not up yet */
546 	if (!(ZS_IS_OPEN(uap) || ZS_IS_CONS(uap)))
547 		return;
548 
549 	set_bits = clear_bits = 0;
550 
551 	if (ZS_IS_INTMODEM(uap)) {
552 		if (mctrl & TIOCM_RTS)
553 			set_bits |= RTS;
554 		else
555 			clear_bits |= RTS;
556 	}
557 	if (mctrl & TIOCM_DTR)
558 		set_bits |= DTR;
559 	else
560 		clear_bits |= DTR;
561 
562 	/* NOTE: Not subject to 'transmitter active' rule.  */
563 	uap->curregs[R5] |= set_bits;
564 	uap->curregs[R5] &= ~clear_bits;
565 
566 	write_zsreg(uap, R5, uap->curregs[R5]);
567 	pmz_debug("pmz_set_mctrl: set bits: %x, clear bits: %x -> %x\n",
568 		  set_bits, clear_bits, uap->curregs[R5]);
569 	zssync(uap);
570 }
571 
572 /*
573  * Get Modem Control bits (only the input ones, the core will
574  * or that with a cached value of the control ones)
575  * The port lock is held and interrupts are disabled.
576  */
577 static unsigned int pmz_get_mctrl(struct uart_port *port)
578 {
579 	struct uart_pmac_port *uap = to_pmz(port);
580 	unsigned char status;
581 	unsigned int ret;
582 
583 	status = read_zsreg(uap, R0);
584 
585 	ret = 0;
586 	if (status & DCD)
587 		ret |= TIOCM_CAR;
588 	if (status & SYNC_HUNT)
589 		ret |= TIOCM_DSR;
590 	if (!(status & CTS))
591 		ret |= TIOCM_CTS;
592 
593 	return ret;
594 }
595 
596 /*
597  * Stop TX side. Dealt like sunzilog at next Tx interrupt,
598  * though for DMA, we will have to do a bit more.
599  * The port lock is held and interrupts are disabled.
600  */
601 static void pmz_stop_tx(struct uart_port *port)
602 {
603 	to_pmz(port)->flags |= PMACZILOG_FLAG_TX_STOPPED;
604 }
605 
606 /*
607  * Kick the Tx side.
608  * The port lock is held and interrupts are disabled.
609  */
610 static void pmz_start_tx(struct uart_port *port)
611 {
612 	struct uart_pmac_port *uap = to_pmz(port);
613 	unsigned char status;
614 
615 	pmz_debug("pmz: start_tx()\n");
616 
617 	uap->flags |= PMACZILOG_FLAG_TX_ACTIVE;
618 	uap->flags &= ~PMACZILOG_FLAG_TX_STOPPED;
619 
620 	status = read_zsreg(uap, R0);
621 
622 	/* TX busy?  Just wait for the TX done interrupt.  */
623 	if (!(status & Tx_BUF_EMP))
624 		return;
625 
626 	/* Send the first character to jump-start the TX done
627 	 * IRQ sending engine.
628 	 */
629 	if (port->x_char) {
630 		write_zsdata(uap, port->x_char);
631 		zssync(uap);
632 		port->icount.tx++;
633 		port->x_char = 0;
634 	} else {
635 		struct circ_buf *xmit = &port->state->xmit;
636 
637 		if (uart_circ_empty(xmit))
638 			goto out;
639 		write_zsdata(uap, xmit->buf[xmit->tail]);
640 		zssync(uap);
641 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
642 		port->icount.tx++;
643 
644 		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
645 			uart_write_wakeup(&uap->port);
646 	}
647  out:
648 	pmz_debug("pmz: start_tx() done.\n");
649 }
650 
651 /*
652  * Stop Rx side, basically disable emitting of
653  * Rx interrupts on the port. We don't disable the rx
654  * side of the chip proper though
655  * The port lock is held.
656  */
657 static void pmz_stop_rx(struct uart_port *port)
658 {
659 	struct uart_pmac_port *uap = to_pmz(port);
660 
661 	pmz_debug("pmz: stop_rx()()\n");
662 
663 	/* Disable all RX interrupts.  */
664 	uap->curregs[R1] &= ~RxINT_MASK;
665 	pmz_maybe_update_regs(uap);
666 
667 	pmz_debug("pmz: stop_rx() done.\n");
668 }
669 
670 /*
671  * Enable modem status change interrupts
672  * The port lock is held.
673  */
674 static void pmz_enable_ms(struct uart_port *port)
675 {
676 	struct uart_pmac_port *uap = to_pmz(port);
677 	unsigned char new_reg;
678 
679 	if (ZS_IS_IRDA(uap))
680 		return;
681 	new_reg = uap->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
682 	if (new_reg != uap->curregs[R15]) {
683 		uap->curregs[R15] = new_reg;
684 
685 		/* NOTE: Not subject to 'transmitter active' rule. */
686 		write_zsreg(uap, R15, uap->curregs[R15]);
687 	}
688 }
689 
690 /*
691  * Control break state emission
692  * The port lock is not held.
693  */
694 static void pmz_break_ctl(struct uart_port *port, int break_state)
695 {
696 	struct uart_pmac_port *uap = to_pmz(port);
697 	unsigned char set_bits, clear_bits, new_reg;
698 	unsigned long flags;
699 
700 	set_bits = clear_bits = 0;
701 
702 	if (break_state)
703 		set_bits |= SND_BRK;
704 	else
705 		clear_bits |= SND_BRK;
706 
707 	spin_lock_irqsave(&port->lock, flags);
708 
709 	new_reg = (uap->curregs[R5] | set_bits) & ~clear_bits;
710 	if (new_reg != uap->curregs[R5]) {
711 		uap->curregs[R5] = new_reg;
712 		write_zsreg(uap, R5, uap->curregs[R5]);
713 	}
714 
715 	spin_unlock_irqrestore(&port->lock, flags);
716 }
717 
718 #ifdef CONFIG_PPC_PMAC
719 
720 /*
721  * Turn power on or off to the SCC and associated stuff
722  * (port drivers, modem, IR port, etc.)
723  * Returns the number of milliseconds we should wait before
724  * trying to use the port.
725  */
726 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
727 {
728 	int delay = 0;
729 	int rc;
730 
731 	if (state) {
732 		rc = pmac_call_feature(
733 			PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 1);
734 		pmz_debug("port power on result: %d\n", rc);
735 		if (ZS_IS_INTMODEM(uap)) {
736 			rc = pmac_call_feature(
737 				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 1);
738 			delay = 2500;	/* wait for 2.5s before using */
739 			pmz_debug("modem power result: %d\n", rc);
740 		}
741 	} else {
742 		/* TODO: Make that depend on a timer, don't power down
743 		 * immediately
744 		 */
745 		if (ZS_IS_INTMODEM(uap)) {
746 			rc = pmac_call_feature(
747 				PMAC_FTR_MODEM_ENABLE, uap->node, 0, 0);
748 			pmz_debug("port power off result: %d\n", rc);
749 		}
750 		pmac_call_feature(PMAC_FTR_SCC_ENABLE, uap->node, uap->port_type, 0);
751 	}
752 	return delay;
753 }
754 
755 #else
756 
757 static int pmz_set_scc_power(struct uart_pmac_port *uap, int state)
758 {
759 	return 0;
760 }
761 
762 #endif /* !CONFIG_PPC_PMAC */
763 
764 /*
765  * FixZeroBug....Works around a bug in the SCC receiving channel.
766  * Inspired from Darwin code, 15 Sept. 2000  -DanM
767  *
768  * The following sequence prevents a problem that is seen with O'Hare ASICs
769  * (most versions -- also with some Heathrow and Hydra ASICs) where a zero
770  * at the input to the receiver becomes 'stuck' and locks up the receiver.
771  * This problem can occur as a result of a zero bit at the receiver input
772  * coincident with any of the following events:
773  *
774  *	The SCC is initialized (hardware or software).
775  *	A framing error is detected.
776  *	The clocking option changes from synchronous or X1 asynchronous
777  *		clocking to X16, X32, or X64 asynchronous clocking.
778  *	The decoding mode is changed among NRZ, NRZI, FM0, or FM1.
779  *
780  * This workaround attempts to recover from the lockup condition by placing
781  * the SCC in synchronous loopback mode with a fast clock before programming
782  * any of the asynchronous modes.
783  */
784 static void pmz_fix_zero_bug_scc(struct uart_pmac_port *uap)
785 {
786 	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
787 	zssync(uap);
788 	udelay(10);
789 	write_zsreg(uap, 9, (ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB) | NV);
790 	zssync(uap);
791 
792 	write_zsreg(uap, 4, X1CLK | MONSYNC);
793 	write_zsreg(uap, 3, Rx8);
794 	write_zsreg(uap, 5, Tx8 | RTS);
795 	write_zsreg(uap, 9, NV);	/* Didn't we already do this? */
796 	write_zsreg(uap, 11, RCBR | TCBR);
797 	write_zsreg(uap, 12, 0);
798 	write_zsreg(uap, 13, 0);
799 	write_zsreg(uap, 14, (LOOPBAK | BRSRC));
800 	write_zsreg(uap, 14, (LOOPBAK | BRSRC | BRENAB));
801 	write_zsreg(uap, 3, Rx8 | RxENABLE);
802 	write_zsreg(uap, 0, RES_EXT_INT);
803 	write_zsreg(uap, 0, RES_EXT_INT);
804 	write_zsreg(uap, 0, RES_EXT_INT);	/* to kill some time */
805 
806 	/* The channel should be OK now, but it is probably receiving
807 	 * loopback garbage.
808 	 * Switch to asynchronous mode, disable the receiver,
809 	 * and discard everything in the receive buffer.
810 	 */
811 	write_zsreg(uap, 9, NV);
812 	write_zsreg(uap, 4, X16CLK | SB_MASK);
813 	write_zsreg(uap, 3, Rx8);
814 
815 	while (read_zsreg(uap, 0) & Rx_CH_AV) {
816 		(void)read_zsreg(uap, 8);
817 		write_zsreg(uap, 0, RES_EXT_INT);
818 		write_zsreg(uap, 0, ERR_RES);
819 	}
820 }
821 
822 /*
823  * Real startup routine, powers up the hardware and sets up
824  * the SCC. Returns a delay in ms where you need to wait before
825  * actually using the port, this is typically the internal modem
826  * powerup delay. This routine expect the lock to be taken.
827  */
828 static int __pmz_startup(struct uart_pmac_port *uap)
829 {
830 	int pwr_delay = 0;
831 
832 	memset(&uap->curregs, 0, sizeof(uap->curregs));
833 
834 	/* Power up the SCC & underlying hardware (modem/irda) */
835 	pwr_delay = pmz_set_scc_power(uap, 1);
836 
837 	/* Nice buggy HW ... */
838 	pmz_fix_zero_bug_scc(uap);
839 
840 	/* Reset the channel */
841 	uap->curregs[R9] = 0;
842 	write_zsreg(uap, 9, ZS_IS_CHANNEL_A(uap) ? CHRA : CHRB);
843 	zssync(uap);
844 	udelay(10);
845 	write_zsreg(uap, 9, 0);
846 	zssync(uap);
847 
848 	/* Clear the interrupt registers */
849 	write_zsreg(uap, R1, 0);
850 	write_zsreg(uap, R0, ERR_RES);
851 	write_zsreg(uap, R0, ERR_RES);
852 	write_zsreg(uap, R0, RES_H_IUS);
853 	write_zsreg(uap, R0, RES_H_IUS);
854 
855 	/* Setup some valid baud rate */
856 	uap->curregs[R4] = X16CLK | SB1;
857 	uap->curregs[R3] = Rx8;
858 	uap->curregs[R5] = Tx8 | RTS;
859 	if (!ZS_IS_IRDA(uap))
860 		uap->curregs[R5] |= DTR;
861 	uap->curregs[R12] = 0;
862 	uap->curregs[R13] = 0;
863 	uap->curregs[R14] = BRENAB;
864 
865 	/* Clear handshaking, enable BREAK interrupts */
866 	uap->curregs[R15] = BRKIE;
867 
868 	/* Master interrupt enable */
869 	uap->curregs[R9] |= NV | MIE;
870 
871 	pmz_load_zsregs(uap, uap->curregs);
872 
873 	/* Enable receiver and transmitter.  */
874 	write_zsreg(uap, R3, uap->curregs[R3] |= RxENABLE);
875 	write_zsreg(uap, R5, uap->curregs[R5] |= TxENABLE);
876 
877 	/* Remember status for DCD/CTS changes */
878 	uap->prev_status = read_zsreg(uap, R0);
879 
880 	return pwr_delay;
881 }
882 
883 static void pmz_irda_reset(struct uart_pmac_port *uap)
884 {
885 	unsigned long flags;
886 
887 	spin_lock_irqsave(&uap->port.lock, flags);
888 	uap->curregs[R5] |= DTR;
889 	write_zsreg(uap, R5, uap->curregs[R5]);
890 	zssync(uap);
891 	spin_unlock_irqrestore(&uap->port.lock, flags);
892 	msleep(110);
893 
894 	spin_lock_irqsave(&uap->port.lock, flags);
895 	uap->curregs[R5] &= ~DTR;
896 	write_zsreg(uap, R5, uap->curregs[R5]);
897 	zssync(uap);
898 	spin_unlock_irqrestore(&uap->port.lock, flags);
899 	msleep(10);
900 }
901 
902 /*
903  * This is the "normal" startup routine, using the above one
904  * wrapped with the lock and doing a schedule delay
905  */
906 static int pmz_startup(struct uart_port *port)
907 {
908 	struct uart_pmac_port *uap = to_pmz(port);
909 	unsigned long flags;
910 	int pwr_delay = 0;
911 
912 	pmz_debug("pmz: startup()\n");
913 
914 	uap->flags |= PMACZILOG_FLAG_IS_OPEN;
915 
916 	/* A console is never powered down. Else, power up and
917 	 * initialize the chip
918 	 */
919 	if (!ZS_IS_CONS(uap)) {
920 		spin_lock_irqsave(&port->lock, flags);
921 		pwr_delay = __pmz_startup(uap);
922 		spin_unlock_irqrestore(&port->lock, flags);
923 	}
924 	sprintf(uap->irq_name, PMACZILOG_NAME"%d", uap->port.line);
925 	if (request_irq(uap->port.irq, pmz_interrupt, IRQF_SHARED,
926 			uap->irq_name, uap)) {
927 		pmz_error("Unable to register zs interrupt handler.\n");
928 		pmz_set_scc_power(uap, 0);
929 		return -ENXIO;
930 	}
931 
932 	/* Right now, we deal with delay by blocking here, I'll be
933 	 * smarter later on
934 	 */
935 	if (pwr_delay != 0) {
936 		pmz_debug("pmz: delaying %d ms\n", pwr_delay);
937 		msleep(pwr_delay);
938 	}
939 
940 	/* IrDA reset is done now */
941 	if (ZS_IS_IRDA(uap))
942 		pmz_irda_reset(uap);
943 
944 	/* Enable interrupt requests for the channel */
945 	spin_lock_irqsave(&port->lock, flags);
946 	pmz_interrupt_control(uap, 1);
947 	spin_unlock_irqrestore(&port->lock, flags);
948 
949 	pmz_debug("pmz: startup() done.\n");
950 
951 	return 0;
952 }
953 
954 static void pmz_shutdown(struct uart_port *port)
955 {
956 	struct uart_pmac_port *uap = to_pmz(port);
957 	unsigned long flags;
958 
959 	pmz_debug("pmz: shutdown()\n");
960 
961 	spin_lock_irqsave(&port->lock, flags);
962 
963 	/* Disable interrupt requests for the channel */
964 	pmz_interrupt_control(uap, 0);
965 
966 	if (!ZS_IS_CONS(uap)) {
967 		/* Disable receiver and transmitter */
968 		uap->curregs[R3] &= ~RxENABLE;
969 		uap->curregs[R5] &= ~TxENABLE;
970 
971 		/* Disable break assertion */
972 		uap->curregs[R5] &= ~SND_BRK;
973 		pmz_maybe_update_regs(uap);
974 	}
975 
976 	spin_unlock_irqrestore(&port->lock, flags);
977 
978 	/* Release interrupt handler */
979 	free_irq(uap->port.irq, uap);
980 
981 	spin_lock_irqsave(&port->lock, flags);
982 
983 	uap->flags &= ~PMACZILOG_FLAG_IS_OPEN;
984 
985 	if (!ZS_IS_CONS(uap))
986 		pmz_set_scc_power(uap, 0);	/* Shut the chip down */
987 
988 	spin_unlock_irqrestore(&port->lock, flags);
989 
990 	pmz_debug("pmz: shutdown() done.\n");
991 }
992 
993 /* Shared by TTY driver and serial console setup.  The port lock is held
994  * and local interrupts are disabled.
995  */
996 static void pmz_convert_to_zs(struct uart_pmac_port *uap, unsigned int cflag,
997 			      unsigned int iflag, unsigned long baud)
998 {
999 	int brg;
1000 
1001 	/* Switch to external clocking for IrDA high clock rates. That
1002 	 * code could be re-used for Midi interfaces with different
1003 	 * multipliers
1004 	 */
1005 	if (baud >= 115200 && ZS_IS_IRDA(uap)) {
1006 		uap->curregs[R4] = X1CLK;
1007 		uap->curregs[R11] = RCTRxCP | TCTRxCP;
1008 		uap->curregs[R14] = 0; /* BRG off */
1009 		uap->curregs[R12] = 0;
1010 		uap->curregs[R13] = 0;
1011 		uap->flags |= PMACZILOG_FLAG_IS_EXTCLK;
1012 	} else {
1013 		switch (baud) {
1014 		case ZS_CLOCK/16:	/* 230400 */
1015 			uap->curregs[R4] = X16CLK;
1016 			uap->curregs[R11] = 0;
1017 			uap->curregs[R14] = 0;
1018 			break;
1019 		case ZS_CLOCK/32:	/* 115200 */
1020 			uap->curregs[R4] = X32CLK;
1021 			uap->curregs[R11] = 0;
1022 			uap->curregs[R14] = 0;
1023 			break;
1024 		default:
1025 			uap->curregs[R4] = X16CLK;
1026 			uap->curregs[R11] = TCBR | RCBR;
1027 			brg = BPS_TO_BRG(baud, ZS_CLOCK / 16);
1028 			uap->curregs[R12] = (brg & 255);
1029 			uap->curregs[R13] = ((brg >> 8) & 255);
1030 			uap->curregs[R14] = BRENAB;
1031 		}
1032 		uap->flags &= ~PMACZILOG_FLAG_IS_EXTCLK;
1033 	}
1034 
1035 	/* Character size, stop bits, and parity. */
1036 	uap->curregs[3] &= ~RxN_MASK;
1037 	uap->curregs[5] &= ~TxN_MASK;
1038 
1039 	switch (cflag & CSIZE) {
1040 	case CS5:
1041 		uap->curregs[3] |= Rx5;
1042 		uap->curregs[5] |= Tx5;
1043 		uap->parity_mask = 0x1f;
1044 		break;
1045 	case CS6:
1046 		uap->curregs[3] |= Rx6;
1047 		uap->curregs[5] |= Tx6;
1048 		uap->parity_mask = 0x3f;
1049 		break;
1050 	case CS7:
1051 		uap->curregs[3] |= Rx7;
1052 		uap->curregs[5] |= Tx7;
1053 		uap->parity_mask = 0x7f;
1054 		break;
1055 	case CS8:
1056 	default:
1057 		uap->curregs[3] |= Rx8;
1058 		uap->curregs[5] |= Tx8;
1059 		uap->parity_mask = 0xff;
1060 		break;
1061 	}
1062 	uap->curregs[4] &= ~(SB_MASK);
1063 	if (cflag & CSTOPB)
1064 		uap->curregs[4] |= SB2;
1065 	else
1066 		uap->curregs[4] |= SB1;
1067 	if (cflag & PARENB)
1068 		uap->curregs[4] |= PAR_ENAB;
1069 	else
1070 		uap->curregs[4] &= ~PAR_ENAB;
1071 	if (!(cflag & PARODD))
1072 		uap->curregs[4] |= PAR_EVEN;
1073 	else
1074 		uap->curregs[4] &= ~PAR_EVEN;
1075 
1076 	uap->port.read_status_mask = Rx_OVR;
1077 	if (iflag & INPCK)
1078 		uap->port.read_status_mask |= CRC_ERR | PAR_ERR;
1079 	if (iflag & (IGNBRK | BRKINT | PARMRK))
1080 		uap->port.read_status_mask |= BRK_ABRT;
1081 
1082 	uap->port.ignore_status_mask = 0;
1083 	if (iflag & IGNPAR)
1084 		uap->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
1085 	if (iflag & IGNBRK) {
1086 		uap->port.ignore_status_mask |= BRK_ABRT;
1087 		if (iflag & IGNPAR)
1088 			uap->port.ignore_status_mask |= Rx_OVR;
1089 	}
1090 
1091 	if ((cflag & CREAD) == 0)
1092 		uap->port.ignore_status_mask = 0xff;
1093 }
1094 
1095 
1096 /*
1097  * Set the irda codec on the imac to the specified baud rate.
1098  */
1099 static void pmz_irda_setup(struct uart_pmac_port *uap, unsigned long *baud)
1100 {
1101 	u8 cmdbyte;
1102 	int t, version;
1103 
1104 	switch (*baud) {
1105 	/* SIR modes */
1106 	case 2400:
1107 		cmdbyte = 0x53;
1108 		break;
1109 	case 4800:
1110 		cmdbyte = 0x52;
1111 		break;
1112 	case 9600:
1113 		cmdbyte = 0x51;
1114 		break;
1115 	case 19200:
1116 		cmdbyte = 0x50;
1117 		break;
1118 	case 38400:
1119 		cmdbyte = 0x4f;
1120 		break;
1121 	case 57600:
1122 		cmdbyte = 0x4e;
1123 		break;
1124 	case 115200:
1125 		cmdbyte = 0x4d;
1126 		break;
1127 	/* The FIR modes aren't really supported at this point, how
1128 	 * do we select the speed ? via the FCR on KeyLargo ?
1129 	 */
1130 	case 1152000:
1131 		cmdbyte = 0;
1132 		break;
1133 	case 4000000:
1134 		cmdbyte = 0;
1135 		break;
1136 	default: /* 9600 */
1137 		cmdbyte = 0x51;
1138 		*baud = 9600;
1139 		break;
1140 	}
1141 
1142 	/* Wait for transmitter to drain */
1143 	t = 10000;
1144 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0
1145 	       || (read_zsreg(uap, R1) & ALL_SNT) == 0) {
1146 		if (--t <= 0) {
1147 			pmz_error("transmitter didn't drain\n");
1148 			return;
1149 		}
1150 		udelay(10);
1151 	}
1152 
1153 	/* Drain the receiver too */
1154 	t = 100;
1155 	(void)read_zsdata(uap);
1156 	(void)read_zsdata(uap);
1157 	(void)read_zsdata(uap);
1158 	mdelay(10);
1159 	while (read_zsreg(uap, R0) & Rx_CH_AV) {
1160 		read_zsdata(uap);
1161 		mdelay(10);
1162 		if (--t <= 0) {
1163 			pmz_error("receiver didn't drain\n");
1164 			return;
1165 		}
1166 	}
1167 
1168 	/* Switch to command mode */
1169 	uap->curregs[R5] |= DTR;
1170 	write_zsreg(uap, R5, uap->curregs[R5]);
1171 	zssync(uap);
1172 	mdelay(1);
1173 
1174 	/* Switch SCC to 19200 */
1175 	pmz_convert_to_zs(uap, CS8, 0, 19200);
1176 	pmz_load_zsregs(uap, uap->curregs);
1177 	mdelay(1);
1178 
1179 	/* Write get_version command byte */
1180 	write_zsdata(uap, 1);
1181 	t = 5000;
1182 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1183 		if (--t <= 0) {
1184 			pmz_error("irda_setup timed out on get_version byte\n");
1185 			goto out;
1186 		}
1187 		udelay(10);
1188 	}
1189 	version = read_zsdata(uap);
1190 
1191 	if (version < 4) {
1192 		pmz_info("IrDA: dongle version %d not supported\n", version);
1193 		goto out;
1194 	}
1195 
1196 	/* Send speed mode */
1197 	write_zsdata(uap, cmdbyte);
1198 	t = 5000;
1199 	while ((read_zsreg(uap, R0) & Rx_CH_AV) == 0) {
1200 		if (--t <= 0) {
1201 			pmz_error("irda_setup timed out on speed mode byte\n");
1202 			goto out;
1203 		}
1204 		udelay(10);
1205 	}
1206 	t = read_zsdata(uap);
1207 	if (t != cmdbyte)
1208 		pmz_error("irda_setup speed mode byte = %x (%x)\n", t, cmdbyte);
1209 
1210 	pmz_info("IrDA setup for %ld bps, dongle version: %d\n",
1211 		 *baud, version);
1212 
1213 	(void)read_zsdata(uap);
1214 	(void)read_zsdata(uap);
1215 	(void)read_zsdata(uap);
1216 
1217  out:
1218 	/* Switch back to data mode */
1219 	uap->curregs[R5] &= ~DTR;
1220 	write_zsreg(uap, R5, uap->curregs[R5]);
1221 	zssync(uap);
1222 
1223 	(void)read_zsdata(uap);
1224 	(void)read_zsdata(uap);
1225 	(void)read_zsdata(uap);
1226 }
1227 
1228 
1229 static void __pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1230 			      struct ktermios *old)
1231 {
1232 	struct uart_pmac_port *uap = to_pmz(port);
1233 	unsigned long baud;
1234 
1235 	pmz_debug("pmz: set_termios()\n");
1236 
1237 	memcpy(&uap->termios_cache, termios, sizeof(struct ktermios));
1238 
1239 	/* XXX Check which revs of machines actually allow 1 and 4Mb speeds
1240 	 * on the IR dongle. Note that the IRTTY driver currently doesn't know
1241 	 * about the FIR mode and high speed modes. So these are unused. For
1242 	 * implementing proper support for these, we should probably add some
1243 	 * DMA as well, at least on the Rx side, which isn't a simple thing
1244 	 * at this point.
1245 	 */
1246 	if (ZS_IS_IRDA(uap)) {
1247 		/* Calc baud rate */
1248 		baud = uart_get_baud_rate(port, termios, old, 1200, 4000000);
1249 		pmz_debug("pmz: switch IRDA to %ld bauds\n", baud);
1250 		/* Cet the irda codec to the right rate */
1251 		pmz_irda_setup(uap, &baud);
1252 		/* Set final baud rate */
1253 		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1254 		pmz_load_zsregs(uap, uap->curregs);
1255 		zssync(uap);
1256 	} else {
1257 		baud = uart_get_baud_rate(port, termios, old, 1200, 230400);
1258 		pmz_convert_to_zs(uap, termios->c_cflag, termios->c_iflag, baud);
1259 		/* Make sure modem status interrupts are correctly configured */
1260 		if (UART_ENABLE_MS(&uap->port, termios->c_cflag)) {
1261 			uap->curregs[R15] |= DCDIE | SYNCIE | CTSIE;
1262 			uap->flags |= PMACZILOG_FLAG_MODEM_STATUS;
1263 		} else {
1264 			uap->curregs[R15] &= ~(DCDIE | SYNCIE | CTSIE);
1265 			uap->flags &= ~PMACZILOG_FLAG_MODEM_STATUS;
1266 		}
1267 
1268 		/* Load registers to the chip */
1269 		pmz_maybe_update_regs(uap);
1270 	}
1271 	uart_update_timeout(port, termios->c_cflag, baud);
1272 
1273 	pmz_debug("pmz: set_termios() done.\n");
1274 }
1275 
1276 /* The port lock is not held.  */
1277 static void pmz_set_termios(struct uart_port *port, struct ktermios *termios,
1278 			    struct ktermios *old)
1279 {
1280 	struct uart_pmac_port *uap = to_pmz(port);
1281 	unsigned long flags;
1282 
1283 	spin_lock_irqsave(&port->lock, flags);
1284 
1285 	/* Disable IRQs on the port */
1286 	pmz_interrupt_control(uap, 0);
1287 
1288 	/* Setup new port configuration */
1289 	__pmz_set_termios(port, termios, old);
1290 
1291 	/* Re-enable IRQs on the port */
1292 	if (ZS_IS_OPEN(uap))
1293 		pmz_interrupt_control(uap, 1);
1294 
1295 	spin_unlock_irqrestore(&port->lock, flags);
1296 }
1297 
1298 static const char *pmz_type(struct uart_port *port)
1299 {
1300 	struct uart_pmac_port *uap = to_pmz(port);
1301 
1302 	if (ZS_IS_IRDA(uap))
1303 		return "Z85c30 ESCC - Infrared port";
1304 	else if (ZS_IS_INTMODEM(uap))
1305 		return "Z85c30 ESCC - Internal modem";
1306 	return "Z85c30 ESCC - Serial port";
1307 }
1308 
1309 /* We do not request/release mappings of the registers here, this
1310  * happens at early serial probe time.
1311  */
1312 static void pmz_release_port(struct uart_port *port)
1313 {
1314 }
1315 
1316 static int pmz_request_port(struct uart_port *port)
1317 {
1318 	return 0;
1319 }
1320 
1321 /* These do not need to do anything interesting either.  */
1322 static void pmz_config_port(struct uart_port *port, int flags)
1323 {
1324 }
1325 
1326 /* We do not support letting the user mess with the divisor, IRQ, etc. */
1327 static int pmz_verify_port(struct uart_port *port, struct serial_struct *ser)
1328 {
1329 	return -EINVAL;
1330 }
1331 
1332 #ifdef CONFIG_CONSOLE_POLL
1333 
1334 static int pmz_poll_get_char(struct uart_port *port)
1335 {
1336 	struct uart_pmac_port *uap =
1337 		container_of(port, struct uart_pmac_port, port);
1338 	int tries = 2;
1339 
1340 	while (tries) {
1341 		if ((read_zsreg(uap, R0) & Rx_CH_AV) != 0)
1342 			return read_zsdata(uap);
1343 		if (tries--)
1344 			udelay(5);
1345 	}
1346 
1347 	return NO_POLL_CHAR;
1348 }
1349 
1350 static void pmz_poll_put_char(struct uart_port *port, unsigned char c)
1351 {
1352 	struct uart_pmac_port *uap =
1353 		container_of(port, struct uart_pmac_port, port);
1354 
1355 	/* Wait for the transmit buffer to empty. */
1356 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1357 		udelay(5);
1358 	write_zsdata(uap, c);
1359 }
1360 
1361 #endif /* CONFIG_CONSOLE_POLL */
1362 
1363 static const struct uart_ops pmz_pops = {
1364 	.tx_empty	=	pmz_tx_empty,
1365 	.set_mctrl	=	pmz_set_mctrl,
1366 	.get_mctrl	=	pmz_get_mctrl,
1367 	.stop_tx	=	pmz_stop_tx,
1368 	.start_tx	=	pmz_start_tx,
1369 	.stop_rx	=	pmz_stop_rx,
1370 	.enable_ms	=	pmz_enable_ms,
1371 	.break_ctl	=	pmz_break_ctl,
1372 	.startup	=	pmz_startup,
1373 	.shutdown	=	pmz_shutdown,
1374 	.set_termios	=	pmz_set_termios,
1375 	.type		=	pmz_type,
1376 	.release_port	=	pmz_release_port,
1377 	.request_port	=	pmz_request_port,
1378 	.config_port	=	pmz_config_port,
1379 	.verify_port	=	pmz_verify_port,
1380 #ifdef CONFIG_CONSOLE_POLL
1381 	.poll_get_char	=	pmz_poll_get_char,
1382 	.poll_put_char	=	pmz_poll_put_char,
1383 #endif
1384 };
1385 
1386 #ifdef CONFIG_PPC_PMAC
1387 
1388 /*
1389  * Setup one port structure after probing, HW is down at this point,
1390  * Unlike sunzilog, we don't need to pre-init the spinlock as we don't
1391  * register our console before uart_add_one_port() is called
1392  */
1393 static int __init pmz_init_port(struct uart_pmac_port *uap)
1394 {
1395 	struct device_node *np = uap->node;
1396 	const char *conn;
1397 	const struct slot_names_prop {
1398 		int	count;
1399 		char	name[1];
1400 	} *slots;
1401 	int len;
1402 	struct resource r_ports, r_rxdma, r_txdma;
1403 
1404 	/*
1405 	 * Request & map chip registers
1406 	 */
1407 	if (of_address_to_resource(np, 0, &r_ports))
1408 		return -ENODEV;
1409 	uap->port.mapbase = r_ports.start;
1410 	uap->port.membase = ioremap(uap->port.mapbase, 0x1000);
1411 
1412 	uap->control_reg = uap->port.membase;
1413 	uap->data_reg = uap->control_reg + 0x10;
1414 
1415 	/*
1416 	 * Request & map DBDMA registers
1417 	 */
1418 #ifdef HAS_DBDMA
1419 	if (of_address_to_resource(np, 1, &r_txdma) == 0 &&
1420 	    of_address_to_resource(np, 2, &r_rxdma) == 0)
1421 		uap->flags |= PMACZILOG_FLAG_HAS_DMA;
1422 #else
1423 	memset(&r_txdma, 0, sizeof(struct resource));
1424 	memset(&r_rxdma, 0, sizeof(struct resource));
1425 #endif
1426 	if (ZS_HAS_DMA(uap)) {
1427 		uap->tx_dma_regs = ioremap(r_txdma.start, 0x100);
1428 		if (uap->tx_dma_regs == NULL) {
1429 			uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
1430 			goto no_dma;
1431 		}
1432 		uap->rx_dma_regs = ioremap(r_rxdma.start, 0x100);
1433 		if (uap->rx_dma_regs == NULL) {
1434 			iounmap(uap->tx_dma_regs);
1435 			uap->tx_dma_regs = NULL;
1436 			uap->flags &= ~PMACZILOG_FLAG_HAS_DMA;
1437 			goto no_dma;
1438 		}
1439 		uap->tx_dma_irq = irq_of_parse_and_map(np, 1);
1440 		uap->rx_dma_irq = irq_of_parse_and_map(np, 2);
1441 	}
1442 no_dma:
1443 
1444 	/*
1445 	 * Detect port type
1446 	 */
1447 	if (of_device_is_compatible(np, "cobalt"))
1448 		uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1449 	conn = of_get_property(np, "AAPL,connector", &len);
1450 	if (conn && (strcmp(conn, "infrared") == 0))
1451 		uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1452 	uap->port_type = PMAC_SCC_ASYNC;
1453 	/* 1999 Powerbook G3 has slot-names property instead */
1454 	slots = of_get_property(np, "slot-names", &len);
1455 	if (slots && slots->count > 0) {
1456 		if (strcmp(slots->name, "IrDA") == 0)
1457 			uap->flags |= PMACZILOG_FLAG_IS_IRDA;
1458 		else if (strcmp(slots->name, "Modem") == 0)
1459 			uap->flags |= PMACZILOG_FLAG_IS_INTMODEM;
1460 	}
1461 	if (ZS_IS_IRDA(uap))
1462 		uap->port_type = PMAC_SCC_IRDA;
1463 	if (ZS_IS_INTMODEM(uap)) {
1464 		struct device_node* i2c_modem =
1465 			of_find_node_by_name(NULL, "i2c-modem");
1466 		if (i2c_modem) {
1467 			const char* mid =
1468 				of_get_property(i2c_modem, "modem-id", NULL);
1469 			if (mid) switch(*mid) {
1470 			case 0x04 :
1471 			case 0x05 :
1472 			case 0x07 :
1473 			case 0x08 :
1474 			case 0x0b :
1475 			case 0x0c :
1476 				uap->port_type = PMAC_SCC_I2S1;
1477 			}
1478 			printk(KERN_INFO "pmac_zilog: i2c-modem detected, id: %d\n",
1479 				mid ? (*mid) : 0);
1480 			of_node_put(i2c_modem);
1481 		} else {
1482 			printk(KERN_INFO "pmac_zilog: serial modem detected\n");
1483 		}
1484 	}
1485 
1486 	/*
1487 	 * Init remaining bits of "port" structure
1488 	 */
1489 	uap->port.iotype = UPIO_MEM;
1490 	uap->port.irq = irq_of_parse_and_map(np, 0);
1491 	uap->port.uartclk = ZS_CLOCK;
1492 	uap->port.fifosize = 1;
1493 	uap->port.ops = &pmz_pops;
1494 	uap->port.type = PORT_PMAC_ZILOG;
1495 	uap->port.flags = 0;
1496 
1497 	/*
1498 	 * Fixup for the port on Gatwick for which the device-tree has
1499 	 * missing interrupts. Normally, the macio_dev would contain
1500 	 * fixed up interrupt info, but we use the device-tree directly
1501 	 * here due to early probing so we need the fixup too.
1502 	 */
1503 	if (uap->port.irq == 0 &&
1504 	    np->parent && np->parent->parent &&
1505 	    of_device_is_compatible(np->parent->parent, "gatwick")) {
1506 		/* IRQs on gatwick are offset by 64 */
1507 		uap->port.irq = irq_create_mapping(NULL, 64 + 15);
1508 		uap->tx_dma_irq = irq_create_mapping(NULL, 64 + 4);
1509 		uap->rx_dma_irq = irq_create_mapping(NULL, 64 + 5);
1510 	}
1511 
1512 	/* Setup some valid baud rate information in the register
1513 	 * shadows so we don't write crap there before baud rate is
1514 	 * first initialized.
1515 	 */
1516 	pmz_convert_to_zs(uap, CS8, 0, 9600);
1517 
1518 	return 0;
1519 }
1520 
1521 /*
1522  * Get rid of a port on module removal
1523  */
1524 static void pmz_dispose_port(struct uart_pmac_port *uap)
1525 {
1526 	struct device_node *np;
1527 
1528 	np = uap->node;
1529 	iounmap(uap->rx_dma_regs);
1530 	iounmap(uap->tx_dma_regs);
1531 	iounmap(uap->control_reg);
1532 	uap->node = NULL;
1533 	of_node_put(np);
1534 	memset(uap, 0, sizeof(struct uart_pmac_port));
1535 }
1536 
1537 /*
1538  * Called upon match with an escc node in the device-tree.
1539  */
1540 static int pmz_attach(struct macio_dev *mdev, const struct of_device_id *match)
1541 {
1542 	struct uart_pmac_port *uap;
1543 	int i;
1544 
1545 	/* Iterate the pmz_ports array to find a matching entry
1546 	 */
1547 	for (i = 0; i < MAX_ZS_PORTS; i++)
1548 		if (pmz_ports[i].node == mdev->ofdev.dev.of_node)
1549 			break;
1550 	if (i >= MAX_ZS_PORTS)
1551 		return -ENODEV;
1552 
1553 
1554 	uap = &pmz_ports[i];
1555 	uap->dev = mdev;
1556 	uap->port.dev = &mdev->ofdev.dev;
1557 	dev_set_drvdata(&mdev->ofdev.dev, uap);
1558 
1559 	/* We still activate the port even when failing to request resources
1560 	 * to work around bugs in ancient Apple device-trees
1561 	 */
1562 	if (macio_request_resources(uap->dev, "pmac_zilog"))
1563 		printk(KERN_WARNING "%pOFn: Failed to request resource"
1564 		       ", port still active\n",
1565 		       uap->node);
1566 	else
1567 		uap->flags |= PMACZILOG_FLAG_RSRC_REQUESTED;
1568 
1569 	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1570 }
1571 
1572 /*
1573  * That one should not be called, macio isn't really a hotswap device,
1574  * we don't expect one of those serial ports to go away...
1575  */
1576 static int pmz_detach(struct macio_dev *mdev)
1577 {
1578 	struct uart_pmac_port	*uap = dev_get_drvdata(&mdev->ofdev.dev);
1579 
1580 	if (!uap)
1581 		return -ENODEV;
1582 
1583 	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1584 
1585 	if (uap->flags & PMACZILOG_FLAG_RSRC_REQUESTED) {
1586 		macio_release_resources(uap->dev);
1587 		uap->flags &= ~PMACZILOG_FLAG_RSRC_REQUESTED;
1588 	}
1589 	dev_set_drvdata(&mdev->ofdev.dev, NULL);
1590 	uap->dev = NULL;
1591 	uap->port.dev = NULL;
1592 
1593 	return 0;
1594 }
1595 
1596 
1597 static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
1598 {
1599 	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1600 
1601 	if (uap == NULL) {
1602 		printk("HRM... pmz_suspend with NULL uap\n");
1603 		return 0;
1604 	}
1605 
1606 	uart_suspend_port(&pmz_uart_reg, &uap->port);
1607 
1608 	return 0;
1609 }
1610 
1611 
1612 static int pmz_resume(struct macio_dev *mdev)
1613 {
1614 	struct uart_pmac_port *uap = dev_get_drvdata(&mdev->ofdev.dev);
1615 
1616 	if (uap == NULL)
1617 		return 0;
1618 
1619 	uart_resume_port(&pmz_uart_reg, &uap->port);
1620 
1621 	return 0;
1622 }
1623 
1624 /*
1625  * Probe all ports in the system and build the ports array, we register
1626  * with the serial layer later, so we get a proper struct device which
1627  * allows the tty to attach properly. This is later than it used to be
1628  * but the tty layer really wants it that way.
1629  */
1630 static int __init pmz_probe(void)
1631 {
1632 	struct device_node	*node_p, *node_a, *node_b, *np;
1633 	int			count = 0;
1634 	int			rc;
1635 
1636 	/*
1637 	 * Find all escc chips in the system
1638 	 */
1639 	for_each_node_by_name(node_p, "escc") {
1640 		/*
1641 		 * First get channel A/B node pointers
1642 		 *
1643 		 * TODO: Add routines with proper locking to do that...
1644 		 */
1645 		node_a = node_b = NULL;
1646 		for (np = NULL; (np = of_get_next_child(node_p, np)) != NULL;) {
1647 			if (of_node_name_prefix(np, "ch-a"))
1648 				node_a = of_node_get(np);
1649 			else if (of_node_name_prefix(np, "ch-b"))
1650 				node_b = of_node_get(np);
1651 		}
1652 		if (!node_a && !node_b) {
1653 			of_node_put(node_a);
1654 			of_node_put(node_b);
1655 			printk(KERN_ERR "pmac_zilog: missing node %c for escc %pOF\n",
1656 				(!node_a) ? 'a' : 'b', node_p);
1657 			continue;
1658 		}
1659 
1660 		/*
1661 		 * Fill basic fields in the port structures
1662 		 */
1663 		if (node_b != NULL) {
1664 			pmz_ports[count].mate		= &pmz_ports[count+1];
1665 			pmz_ports[count+1].mate		= &pmz_ports[count];
1666 		}
1667 		pmz_ports[count].flags		= PMACZILOG_FLAG_IS_CHANNEL_A;
1668 		pmz_ports[count].node		= node_a;
1669 		pmz_ports[count+1].node		= node_b;
1670 		pmz_ports[count].port.line	= count;
1671 		pmz_ports[count+1].port.line	= count+1;
1672 
1673 		/*
1674 		 * Setup the ports for real
1675 		 */
1676 		rc = pmz_init_port(&pmz_ports[count]);
1677 		if (rc == 0 && node_b != NULL)
1678 			rc = pmz_init_port(&pmz_ports[count+1]);
1679 		if (rc != 0) {
1680 			of_node_put(node_a);
1681 			of_node_put(node_b);
1682 			memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
1683 			memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
1684 			continue;
1685 		}
1686 		count += 2;
1687 	}
1688 	pmz_ports_count = count;
1689 
1690 	return 0;
1691 }
1692 
1693 #else
1694 
1695 extern struct platform_device scc_a_pdev, scc_b_pdev;
1696 
1697 static int __init pmz_init_port(struct uart_pmac_port *uap)
1698 {
1699 	struct resource *r_ports;
1700 	int irq;
1701 
1702 	r_ports = platform_get_resource(uap->pdev, IORESOURCE_MEM, 0);
1703 	irq = platform_get_irq(uap->pdev, 0);
1704 	if (!r_ports || irq <= 0)
1705 		return -ENODEV;
1706 
1707 	uap->port.mapbase  = r_ports->start;
1708 	uap->port.membase  = (unsigned char __iomem *) r_ports->start;
1709 	uap->port.iotype   = UPIO_MEM;
1710 	uap->port.irq      = irq;
1711 	uap->port.uartclk  = ZS_CLOCK;
1712 	uap->port.fifosize = 1;
1713 	uap->port.ops      = &pmz_pops;
1714 	uap->port.type     = PORT_PMAC_ZILOG;
1715 	uap->port.flags    = 0;
1716 
1717 	uap->control_reg   = uap->port.membase;
1718 	uap->data_reg      = uap->control_reg + 4;
1719 	uap->port_type     = 0;
1720 	uap->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_PMACZILOG_CONSOLE);
1721 
1722 	pmz_convert_to_zs(uap, CS8, 0, 9600);
1723 
1724 	return 0;
1725 }
1726 
1727 static int __init pmz_probe(void)
1728 {
1729 	int err;
1730 
1731 	pmz_ports_count = 0;
1732 
1733 	pmz_ports[0].port.line = 0;
1734 	pmz_ports[0].flags     = PMACZILOG_FLAG_IS_CHANNEL_A;
1735 	pmz_ports[0].pdev      = &scc_a_pdev;
1736 	err = pmz_init_port(&pmz_ports[0]);
1737 	if (err)
1738 		return err;
1739 	pmz_ports_count++;
1740 
1741 	pmz_ports[0].mate      = &pmz_ports[1];
1742 	pmz_ports[1].mate      = &pmz_ports[0];
1743 	pmz_ports[1].port.line = 1;
1744 	pmz_ports[1].flags     = 0;
1745 	pmz_ports[1].pdev      = &scc_b_pdev;
1746 	err = pmz_init_port(&pmz_ports[1]);
1747 	if (err)
1748 		return err;
1749 	pmz_ports_count++;
1750 
1751 	return 0;
1752 }
1753 
1754 static void pmz_dispose_port(struct uart_pmac_port *uap)
1755 {
1756 	memset(uap, 0, sizeof(struct uart_pmac_port));
1757 }
1758 
1759 static int __init pmz_attach(struct platform_device *pdev)
1760 {
1761 	struct uart_pmac_port *uap;
1762 	int i;
1763 
1764 	/* Iterate the pmz_ports array to find a matching entry */
1765 	for (i = 0; i < pmz_ports_count; i++)
1766 		if (pmz_ports[i].pdev == pdev)
1767 			break;
1768 	if (i >= pmz_ports_count)
1769 		return -ENODEV;
1770 
1771 	uap = &pmz_ports[i];
1772 	uap->port.dev = &pdev->dev;
1773 	platform_set_drvdata(pdev, uap);
1774 
1775 	return uart_add_one_port(&pmz_uart_reg, &uap->port);
1776 }
1777 
1778 static int __exit pmz_detach(struct platform_device *pdev)
1779 {
1780 	struct uart_pmac_port *uap = platform_get_drvdata(pdev);
1781 
1782 	if (!uap)
1783 		return -ENODEV;
1784 
1785 	uart_remove_one_port(&pmz_uart_reg, &uap->port);
1786 
1787 	uap->port.dev = NULL;
1788 
1789 	return 0;
1790 }
1791 
1792 #endif /* !CONFIG_PPC_PMAC */
1793 
1794 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1795 
1796 static void pmz_console_write(struct console *con, const char *s, unsigned int count);
1797 static int __init pmz_console_setup(struct console *co, char *options);
1798 
1799 static struct console pmz_console = {
1800 	.name	=	PMACZILOG_NAME,
1801 	.write	=	pmz_console_write,
1802 	.device	=	uart_console_device,
1803 	.setup	=	pmz_console_setup,
1804 	.flags	=	CON_PRINTBUFFER,
1805 	.index	=	-1,
1806 	.data   =	&pmz_uart_reg,
1807 };
1808 
1809 #define PMACZILOG_CONSOLE	&pmz_console
1810 #else /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1811 #define PMACZILOG_CONSOLE	(NULL)
1812 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
1813 
1814 /*
1815  * Register the driver, console driver and ports with the serial
1816  * core
1817  */
1818 static int __init pmz_register(void)
1819 {
1820 	pmz_uart_reg.nr = pmz_ports_count;
1821 	pmz_uart_reg.cons = PMACZILOG_CONSOLE;
1822 
1823 	/*
1824 	 * Register this driver with the serial core
1825 	 */
1826 	return uart_register_driver(&pmz_uart_reg);
1827 }
1828 
1829 #ifdef CONFIG_PPC_PMAC
1830 
1831 static const struct of_device_id pmz_match[] =
1832 {
1833 	{
1834 	.name		= "ch-a",
1835 	},
1836 	{
1837 	.name		= "ch-b",
1838 	},
1839 	{},
1840 };
1841 MODULE_DEVICE_TABLE (of, pmz_match);
1842 
1843 static struct macio_driver pmz_driver = {
1844 	.driver = {
1845 		.name 		= "pmac_zilog",
1846 		.owner		= THIS_MODULE,
1847 		.of_match_table	= pmz_match,
1848 	},
1849 	.probe		= pmz_attach,
1850 	.remove		= pmz_detach,
1851 	.suspend	= pmz_suspend,
1852 	.resume		= pmz_resume,
1853 };
1854 
1855 #else
1856 
1857 static struct platform_driver pmz_driver = {
1858 	.remove		= __exit_p(pmz_detach),
1859 	.driver		= {
1860 		.name		= "scc",
1861 	},
1862 };
1863 
1864 #endif /* !CONFIG_PPC_PMAC */
1865 
1866 static int __init init_pmz(void)
1867 {
1868 	int rc, i;
1869 	printk(KERN_INFO "%s\n", version);
1870 
1871 	/*
1872 	 * First, we need to do a direct OF-based probe pass. We
1873 	 * do that because we want serial console up before the
1874 	 * macio stuffs calls us back, and since that makes it
1875 	 * easier to pass the proper number of channels to
1876 	 * uart_register_driver()
1877 	 */
1878 	if (pmz_ports_count == 0)
1879 		pmz_probe();
1880 
1881 	/*
1882 	 * Bail early if no port found
1883 	 */
1884 	if (pmz_ports_count == 0)
1885 		return -ENODEV;
1886 
1887 	/*
1888 	 * Now we register with the serial layer
1889 	 */
1890 	rc = pmz_register();
1891 	if (rc) {
1892 		printk(KERN_ERR
1893 			"pmac_zilog: Error registering serial device, disabling pmac_zilog.\n"
1894 		 	"pmac_zilog: Did another serial driver already claim the minors?\n");
1895 		/* effectively "pmz_unprobe()" */
1896 		for (i=0; i < pmz_ports_count; i++)
1897 			pmz_dispose_port(&pmz_ports[i]);
1898 		return rc;
1899 	}
1900 
1901 	/*
1902 	 * Then we register the macio driver itself
1903 	 */
1904 #ifdef CONFIG_PPC_PMAC
1905 	return macio_register_driver(&pmz_driver);
1906 #else
1907 	return platform_driver_probe(&pmz_driver, pmz_attach);
1908 #endif
1909 }
1910 
1911 static void __exit exit_pmz(void)
1912 {
1913 	int i;
1914 
1915 #ifdef CONFIG_PPC_PMAC
1916 	/* Get rid of macio-driver (detach from macio) */
1917 	macio_unregister_driver(&pmz_driver);
1918 #else
1919 	platform_driver_unregister(&pmz_driver);
1920 #endif
1921 
1922 	for (i = 0; i < pmz_ports_count; i++) {
1923 		struct uart_pmac_port *uport = &pmz_ports[i];
1924 #ifdef CONFIG_PPC_PMAC
1925 		if (uport->node != NULL)
1926 			pmz_dispose_port(uport);
1927 #else
1928 		if (uport->pdev != NULL)
1929 			pmz_dispose_port(uport);
1930 #endif
1931 	}
1932 	/* Unregister UART driver */
1933 	uart_unregister_driver(&pmz_uart_reg);
1934 }
1935 
1936 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
1937 
1938 static void pmz_console_putchar(struct uart_port *port, int ch)
1939 {
1940 	struct uart_pmac_port *uap =
1941 		container_of(port, struct uart_pmac_port, port);
1942 
1943 	/* Wait for the transmit buffer to empty. */
1944 	while ((read_zsreg(uap, R0) & Tx_BUF_EMP) == 0)
1945 		udelay(5);
1946 	write_zsdata(uap, ch);
1947 }
1948 
1949 /*
1950  * Print a string to the serial port trying not to disturb
1951  * any possible real use of the port...
1952  */
1953 static void pmz_console_write(struct console *con, const char *s, unsigned int count)
1954 {
1955 	struct uart_pmac_port *uap = &pmz_ports[con->index];
1956 	unsigned long flags;
1957 
1958 	spin_lock_irqsave(&uap->port.lock, flags);
1959 
1960 	/* Turn of interrupts and enable the transmitter. */
1961 	write_zsreg(uap, R1, uap->curregs[1] & ~TxINT_ENAB);
1962 	write_zsreg(uap, R5, uap->curregs[5] | TxENABLE | RTS | DTR);
1963 
1964 	uart_console_write(&uap->port, s, count, pmz_console_putchar);
1965 
1966 	/* Restore the values in the registers. */
1967 	write_zsreg(uap, R1, uap->curregs[1]);
1968 	/* Don't disable the transmitter. */
1969 
1970 	spin_unlock_irqrestore(&uap->port.lock, flags);
1971 }
1972 
1973 /*
1974  * Setup the serial console
1975  */
1976 static int __init pmz_console_setup(struct console *co, char *options)
1977 {
1978 	struct uart_pmac_port *uap;
1979 	struct uart_port *port;
1980 	int baud = 38400;
1981 	int bits = 8;
1982 	int parity = 'n';
1983 	int flow = 'n';
1984 	unsigned long pwr_delay;
1985 
1986 	/*
1987 	 * XServe's default to 57600 bps
1988 	 */
1989 	if (of_machine_is_compatible("RackMac1,1")
1990 	    || of_machine_is_compatible("RackMac1,2")
1991 	    || of_machine_is_compatible("MacRISC4"))
1992 		baud = 57600;
1993 
1994 	/*
1995 	 * Check whether an invalid uart number has been specified, and
1996 	 * if so, search for the first available port that does have
1997 	 * console support.
1998 	 */
1999 	if (co->index >= pmz_ports_count)
2000 		co->index = 0;
2001 	uap = &pmz_ports[co->index];
2002 #ifdef CONFIG_PPC_PMAC
2003 	if (uap->node == NULL)
2004 		return -ENODEV;
2005 #else
2006 	if (uap->pdev == NULL)
2007 		return -ENODEV;
2008 #endif
2009 	port = &uap->port;
2010 
2011 	/*
2012 	 * Mark port as beeing a console
2013 	 */
2014 	uap->flags |= PMACZILOG_FLAG_IS_CONS;
2015 
2016 	/*
2017 	 * Temporary fix for uart layer who didn't setup the spinlock yet
2018 	 */
2019 	spin_lock_init(&port->lock);
2020 
2021 	/*
2022 	 * Enable the hardware
2023 	 */
2024 	pwr_delay = __pmz_startup(uap);
2025 	if (pwr_delay)
2026 		mdelay(pwr_delay);
2027 
2028 	if (options)
2029 		uart_parse_options(options, &baud, &parity, &bits, &flow);
2030 
2031 	return uart_set_options(port, co, baud, parity, bits, flow);
2032 }
2033 
2034 static int __init pmz_console_init(void)
2035 {
2036 	/* Probe ports */
2037 	pmz_probe();
2038 
2039 	if (pmz_ports_count == 0)
2040 		return -ENODEV;
2041 
2042 	/* TODO: Autoprobe console based on OF */
2043 	/* pmz_console.index = i; */
2044 	register_console(&pmz_console);
2045 
2046 	return 0;
2047 
2048 }
2049 console_initcall(pmz_console_init);
2050 #endif /* CONFIG_SERIAL_PMACZILOG_CONSOLE */
2051 
2052 module_init(init_pmz);
2053 module_exit(exit_pmz);
2054