xref: /linux/drivers/tty/serial/sunzilog.c (revision d2912cb15bdda8ba4a5dd73396ad62641af2f520)
1 // SPDX-License-Identifier: GPL-2.0
2 /* sunzilog.c: Zilog serial driver for Sparc systems.
3  *
4  * Driver for Zilog serial chips found on Sun workstations and
5  * servers.  This driver could actually be made more generic.
6  *
7  * This is based on the old drivers/sbus/char/zs.c code.  A lot
8  * of code has been simply moved over directly from there but
9  * much has been rewritten.  Credits therefore go out to Eddie
10  * C. Dost, Pete Zaitcev, Ted Ts'o and Alex Buell for their
11  * work there.
12  *
13  * Copyright (C) 2002, 2006, 2007 David S. Miller (davem@davemloft.net)
14  */
15 
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/delay.h>
20 #include <linux/tty.h>
21 #include <linux/tty_flip.h>
22 #include <linux/major.h>
23 #include <linux/string.h>
24 #include <linux/ptrace.h>
25 #include <linux/ioport.h>
26 #include <linux/slab.h>
27 #include <linux/circ_buf.h>
28 #include <linux/serial.h>
29 #include <linux/sysrq.h>
30 #include <linux/console.h>
31 #include <linux/spinlock.h>
32 #ifdef CONFIG_SERIO
33 #include <linux/serio.h>
34 #endif
35 #include <linux/init.h>
36 #include <linux/of_device.h>
37 
38 #include <asm/io.h>
39 #include <asm/irq.h>
40 #include <asm/prom.h>
41 #include <asm/setup.h>
42 
43 #if defined(CONFIG_SERIAL_SUNZILOG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
44 #define SUPPORT_SYSRQ
45 #endif
46 
47 #include <linux/serial_core.h>
48 #include <linux/sunserialcore.h>
49 
50 #include "sunzilog.h"
51 
52 /* On 32-bit sparcs we need to delay after register accesses
53  * to accommodate sun4 systems, but we do not need to flush writes.
54  * On 64-bit sparc we only need to flush single writes to ensure
55  * completion.
56  */
57 #ifndef CONFIG_SPARC64
58 #define ZSDELAY()		udelay(5)
59 #define ZSDELAY_LONG()		udelay(20)
60 #define ZS_WSYNC(channel)	do { } while (0)
61 #else
62 #define ZSDELAY()
63 #define ZSDELAY_LONG()
64 #define ZS_WSYNC(__channel) \
65 	readb(&((__channel)->control))
66 #endif
67 
68 #define ZS_CLOCK		4915200 /* Zilog input clock rate. */
69 #define ZS_CLOCK_DIVISOR	16      /* Divisor this driver uses. */
70 
71 /*
72  * We wrap our port structure around the generic uart_port.
73  */
74 struct uart_sunzilog_port {
75 	struct uart_port		port;
76 
77 	/* IRQ servicing chain.  */
78 	struct uart_sunzilog_port	*next;
79 
80 	/* Current values of Zilog write registers.  */
81 	unsigned char			curregs[NUM_ZSREGS];
82 
83 	unsigned int			flags;
84 #define SUNZILOG_FLAG_CONS_KEYB		0x00000001
85 #define SUNZILOG_FLAG_CONS_MOUSE	0x00000002
86 #define SUNZILOG_FLAG_IS_CONS		0x00000004
87 #define SUNZILOG_FLAG_IS_KGDB		0x00000008
88 #define SUNZILOG_FLAG_MODEM_STATUS	0x00000010
89 #define SUNZILOG_FLAG_IS_CHANNEL_A	0x00000020
90 #define SUNZILOG_FLAG_REGS_HELD		0x00000040
91 #define SUNZILOG_FLAG_TX_STOPPED	0x00000080
92 #define SUNZILOG_FLAG_TX_ACTIVE		0x00000100
93 #define SUNZILOG_FLAG_ESCC		0x00000200
94 #define SUNZILOG_FLAG_ISR_HANDLER	0x00000400
95 
96 	unsigned int cflag;
97 
98 	unsigned char			parity_mask;
99 	unsigned char			prev_status;
100 
101 #ifdef CONFIG_SERIO
102 	struct serio			serio;
103 	int				serio_open;
104 #endif
105 };
106 
107 static void sunzilog_putchar(struct uart_port *port, int ch);
108 
109 #define ZILOG_CHANNEL_FROM_PORT(PORT)	((struct zilog_channel __iomem *)((PORT)->membase))
110 #define UART_ZILOG(PORT)		((struct uart_sunzilog_port *)(PORT))
111 
112 #define ZS_IS_KEYB(UP)	((UP)->flags & SUNZILOG_FLAG_CONS_KEYB)
113 #define ZS_IS_MOUSE(UP)	((UP)->flags & SUNZILOG_FLAG_CONS_MOUSE)
114 #define ZS_IS_CONS(UP)	((UP)->flags & SUNZILOG_FLAG_IS_CONS)
115 #define ZS_IS_KGDB(UP)	((UP)->flags & SUNZILOG_FLAG_IS_KGDB)
116 #define ZS_WANTS_MODEM_STATUS(UP)	((UP)->flags & SUNZILOG_FLAG_MODEM_STATUS)
117 #define ZS_IS_CHANNEL_A(UP)	((UP)->flags & SUNZILOG_FLAG_IS_CHANNEL_A)
118 #define ZS_REGS_HELD(UP)	((UP)->flags & SUNZILOG_FLAG_REGS_HELD)
119 #define ZS_TX_STOPPED(UP)	((UP)->flags & SUNZILOG_FLAG_TX_STOPPED)
120 #define ZS_TX_ACTIVE(UP)	((UP)->flags & SUNZILOG_FLAG_TX_ACTIVE)
121 
122 /* Reading and writing Zilog8530 registers.  The delays are to make this
123  * driver work on the Sun4 which needs a settling delay after each chip
124  * register access, other machines handle this in hardware via auxiliary
125  * flip-flops which implement the settle time we do in software.
126  *
127  * The port lock must be held and local IRQs must be disabled
128  * when {read,write}_zsreg is invoked.
129  */
130 static unsigned char read_zsreg(struct zilog_channel __iomem *channel,
131 				unsigned char reg)
132 {
133 	unsigned char retval;
134 
135 	writeb(reg, &channel->control);
136 	ZSDELAY();
137 	retval = readb(&channel->control);
138 	ZSDELAY();
139 
140 	return retval;
141 }
142 
143 static void write_zsreg(struct zilog_channel __iomem *channel,
144 			unsigned char reg, unsigned char value)
145 {
146 	writeb(reg, &channel->control);
147 	ZSDELAY();
148 	writeb(value, &channel->control);
149 	ZSDELAY();
150 }
151 
152 static void sunzilog_clear_fifo(struct zilog_channel __iomem *channel)
153 {
154 	int i;
155 
156 	for (i = 0; i < 32; i++) {
157 		unsigned char regval;
158 
159 		regval = readb(&channel->control);
160 		ZSDELAY();
161 		if (regval & Rx_CH_AV)
162 			break;
163 
164 		regval = read_zsreg(channel, R1);
165 		readb(&channel->data);
166 		ZSDELAY();
167 
168 		if (regval & (PAR_ERR | Rx_OVR | CRC_ERR)) {
169 			writeb(ERR_RES, &channel->control);
170 			ZSDELAY();
171 			ZS_WSYNC(channel);
172 		}
173 	}
174 }
175 
176 /* This function must only be called when the TX is not busy.  The UART
177  * port lock must be held and local interrupts disabled.
178  */
179 static int __load_zsregs(struct zilog_channel __iomem *channel, unsigned char *regs)
180 {
181 	int i;
182 	int escc;
183 	unsigned char r15;
184 
185 	/* Let pending transmits finish.  */
186 	for (i = 0; i < 1000; i++) {
187 		unsigned char stat = read_zsreg(channel, R1);
188 		if (stat & ALL_SNT)
189 			break;
190 		udelay(100);
191 	}
192 
193 	writeb(ERR_RES, &channel->control);
194 	ZSDELAY();
195 	ZS_WSYNC(channel);
196 
197 	sunzilog_clear_fifo(channel);
198 
199 	/* Disable all interrupts.  */
200 	write_zsreg(channel, R1,
201 		    regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
202 
203 	/* Set parity, sync config, stop bits, and clock divisor.  */
204 	write_zsreg(channel, R4, regs[R4]);
205 
206 	/* Set misc. TX/RX control bits.  */
207 	write_zsreg(channel, R10, regs[R10]);
208 
209 	/* Set TX/RX controls sans the enable bits.  */
210 	write_zsreg(channel, R3, regs[R3] & ~RxENAB);
211 	write_zsreg(channel, R5, regs[R5] & ~TxENAB);
212 
213 	/* Synchronous mode config.  */
214 	write_zsreg(channel, R6, regs[R6]);
215 	write_zsreg(channel, R7, regs[R7]);
216 
217 	/* Don't mess with the interrupt vector (R2, unused by us) and
218 	 * master interrupt control (R9).  We make sure this is setup
219 	 * properly at probe time then never touch it again.
220 	 */
221 
222 	/* Disable baud generator.  */
223 	write_zsreg(channel, R14, regs[R14] & ~BRENAB);
224 
225 	/* Clock mode control.  */
226 	write_zsreg(channel, R11, regs[R11]);
227 
228 	/* Lower and upper byte of baud rate generator divisor.  */
229 	write_zsreg(channel, R12, regs[R12]);
230 	write_zsreg(channel, R13, regs[R13]);
231 
232 	/* Now rewrite R14, with BRENAB (if set).  */
233 	write_zsreg(channel, R14, regs[R14]);
234 
235 	/* External status interrupt control.  */
236 	write_zsreg(channel, R15, (regs[R15] | WR7pEN) & ~FIFOEN);
237 
238 	/* ESCC Extension Register */
239 	r15 = read_zsreg(channel, R15);
240 	if (r15 & 0x01)	{
241 		write_zsreg(channel, R7,  regs[R7p]);
242 
243 		/* External status interrupt and FIFO control.  */
244 		write_zsreg(channel, R15, regs[R15] & ~WR7pEN);
245 		escc = 1;
246 	} else {
247 		 /* Clear FIFO bit case it is an issue */
248 		regs[R15] &= ~FIFOEN;
249 		escc = 0;
250 	}
251 
252 	/* Reset external status interrupts.  */
253 	write_zsreg(channel, R0, RES_EXT_INT); /* First Latch  */
254 	write_zsreg(channel, R0, RES_EXT_INT); /* Second Latch */
255 
256 	/* Rewrite R3/R5, this time without enables masked.  */
257 	write_zsreg(channel, R3, regs[R3]);
258 	write_zsreg(channel, R5, regs[R5]);
259 
260 	/* Rewrite R1, this time without IRQ enabled masked.  */
261 	write_zsreg(channel, R1, regs[R1]);
262 
263 	return escc;
264 }
265 
266 /* Reprogram the Zilog channel HW registers with the copies found in the
267  * software state struct.  If the transmitter is busy, we defer this update
268  * until the next TX complete interrupt.  Else, we do it right now.
269  *
270  * The UART port lock must be held and local interrupts disabled.
271  */
272 static void sunzilog_maybe_update_regs(struct uart_sunzilog_port *up,
273 				       struct zilog_channel __iomem *channel)
274 {
275 	if (!ZS_REGS_HELD(up)) {
276 		if (ZS_TX_ACTIVE(up)) {
277 			up->flags |= SUNZILOG_FLAG_REGS_HELD;
278 		} else {
279 			__load_zsregs(channel, up->curregs);
280 		}
281 	}
282 }
283 
284 static void sunzilog_change_mouse_baud(struct uart_sunzilog_port *up)
285 {
286 	unsigned int cur_cflag = up->cflag;
287 	int brg, new_baud;
288 
289 	up->cflag &= ~CBAUD;
290 	up->cflag |= suncore_mouse_baud_cflag_next(cur_cflag, &new_baud);
291 
292 	brg = BPS_TO_BRG(new_baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
293 	up->curregs[R12] = (brg & 0xff);
294 	up->curregs[R13] = (brg >> 8) & 0xff;
295 	sunzilog_maybe_update_regs(up, ZILOG_CHANNEL_FROM_PORT(&up->port));
296 }
297 
298 static void sunzilog_kbdms_receive_chars(struct uart_sunzilog_port *up,
299 					 unsigned char ch, int is_break)
300 {
301 	if (ZS_IS_KEYB(up)) {
302 		/* Stop-A is handled by drivers/char/keyboard.c now. */
303 #ifdef CONFIG_SERIO
304 		if (up->serio_open)
305 			serio_interrupt(&up->serio, ch, 0);
306 #endif
307 	} else if (ZS_IS_MOUSE(up)) {
308 		int ret = suncore_mouse_baud_detection(ch, is_break);
309 
310 		switch (ret) {
311 		case 2:
312 			sunzilog_change_mouse_baud(up);
313 			/* fallthru */
314 		case 1:
315 			break;
316 
317 		case 0:
318 #ifdef CONFIG_SERIO
319 			if (up->serio_open)
320 				serio_interrupt(&up->serio, ch, 0);
321 #endif
322 			break;
323 		}
324 	}
325 }
326 
327 static struct tty_port *
328 sunzilog_receive_chars(struct uart_sunzilog_port *up,
329 		       struct zilog_channel __iomem *channel)
330 {
331 	struct tty_port *port = NULL;
332 	unsigned char ch, r1, flag;
333 
334 	if (up->port.state != NULL)		/* Unopened serial console */
335 		port = &up->port.state->port;
336 
337 	for (;;) {
338 
339 		r1 = read_zsreg(channel, R1);
340 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
341 			writeb(ERR_RES, &channel->control);
342 			ZSDELAY();
343 			ZS_WSYNC(channel);
344 		}
345 
346 		ch = readb(&channel->control);
347 		ZSDELAY();
348 
349 		/* This funny hack depends upon BRK_ABRT not interfering
350 		 * with the other bits we care about in R1.
351 		 */
352 		if (ch & BRK_ABRT)
353 			r1 |= BRK_ABRT;
354 
355 		if (!(ch & Rx_CH_AV))
356 			break;
357 
358 		ch = readb(&channel->data);
359 		ZSDELAY();
360 
361 		ch &= up->parity_mask;
362 
363 		if (unlikely(ZS_IS_KEYB(up)) || unlikely(ZS_IS_MOUSE(up))) {
364 			sunzilog_kbdms_receive_chars(up, ch, 0);
365 			continue;
366 		}
367 
368 		/* A real serial line, record the character and status.  */
369 		flag = TTY_NORMAL;
370 		up->port.icount.rx++;
371 		if (r1 & (BRK_ABRT | PAR_ERR | Rx_OVR | CRC_ERR)) {
372 			if (r1 & BRK_ABRT) {
373 				r1 &= ~(PAR_ERR | CRC_ERR);
374 				up->port.icount.brk++;
375 				if (uart_handle_break(&up->port))
376 					continue;
377 			}
378 			else if (r1 & PAR_ERR)
379 				up->port.icount.parity++;
380 			else if (r1 & CRC_ERR)
381 				up->port.icount.frame++;
382 			if (r1 & Rx_OVR)
383 				up->port.icount.overrun++;
384 			r1 &= up->port.read_status_mask;
385 			if (r1 & BRK_ABRT)
386 				flag = TTY_BREAK;
387 			else if (r1 & PAR_ERR)
388 				flag = TTY_PARITY;
389 			else if (r1 & CRC_ERR)
390 				flag = TTY_FRAME;
391 		}
392 		if (uart_handle_sysrq_char(&up->port, ch) || !port)
393 			continue;
394 
395 		if (up->port.ignore_status_mask == 0xff ||
396 		    (r1 & up->port.ignore_status_mask) == 0) {
397 		    	tty_insert_flip_char(port, ch, flag);
398 		}
399 		if (r1 & Rx_OVR)
400 			tty_insert_flip_char(port, 0, TTY_OVERRUN);
401 	}
402 
403 	return port;
404 }
405 
406 static void sunzilog_status_handle(struct uart_sunzilog_port *up,
407 				   struct zilog_channel __iomem *channel)
408 {
409 	unsigned char status;
410 
411 	status = readb(&channel->control);
412 	ZSDELAY();
413 
414 	writeb(RES_EXT_INT, &channel->control);
415 	ZSDELAY();
416 	ZS_WSYNC(channel);
417 
418 	if (status & BRK_ABRT) {
419 		if (ZS_IS_MOUSE(up))
420 			sunzilog_kbdms_receive_chars(up, 0, 1);
421 		if (ZS_IS_CONS(up)) {
422 			/* Wait for BREAK to deassert to avoid potentially
423 			 * confusing the PROM.
424 			 */
425 			while (1) {
426 				status = readb(&channel->control);
427 				ZSDELAY();
428 				if (!(status & BRK_ABRT))
429 					break;
430 			}
431 			sun_do_break();
432 			return;
433 		}
434 	}
435 
436 	if (ZS_WANTS_MODEM_STATUS(up)) {
437 		if (status & SYNC)
438 			up->port.icount.dsr++;
439 
440 		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
441 		 * But it does not tell us which bit has changed, we have to keep
442 		 * track of this ourselves.
443 		 */
444 		if ((status ^ up->prev_status) ^ DCD)
445 			uart_handle_dcd_change(&up->port,
446 					       (status & DCD));
447 		if ((status ^ up->prev_status) ^ CTS)
448 			uart_handle_cts_change(&up->port,
449 					       (status & CTS));
450 
451 		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
452 	}
453 
454 	up->prev_status = status;
455 }
456 
457 static void sunzilog_transmit_chars(struct uart_sunzilog_port *up,
458 				    struct zilog_channel __iomem *channel)
459 {
460 	struct circ_buf *xmit;
461 
462 	if (ZS_IS_CONS(up)) {
463 		unsigned char status = readb(&channel->control);
464 		ZSDELAY();
465 
466 		/* TX still busy?  Just wait for the next TX done interrupt.
467 		 *
468 		 * It can occur because of how we do serial console writes.  It would
469 		 * be nice to transmit console writes just like we normally would for
470 		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not
471 		 * easy because console writes cannot sleep.  One solution might be
472 		 * to poll on enough port->xmit space becoming free.  -DaveM
473 		 */
474 		if (!(status & Tx_BUF_EMP))
475 			return;
476 	}
477 
478 	up->flags &= ~SUNZILOG_FLAG_TX_ACTIVE;
479 
480 	if (ZS_REGS_HELD(up)) {
481 		__load_zsregs(channel, up->curregs);
482 		up->flags &= ~SUNZILOG_FLAG_REGS_HELD;
483 	}
484 
485 	if (ZS_TX_STOPPED(up)) {
486 		up->flags &= ~SUNZILOG_FLAG_TX_STOPPED;
487 		goto ack_tx_int;
488 	}
489 
490 	if (up->port.x_char) {
491 		up->flags |= SUNZILOG_FLAG_TX_ACTIVE;
492 		writeb(up->port.x_char, &channel->data);
493 		ZSDELAY();
494 		ZS_WSYNC(channel);
495 
496 		up->port.icount.tx++;
497 		up->port.x_char = 0;
498 		return;
499 	}
500 
501 	if (up->port.state == NULL)
502 		goto ack_tx_int;
503 	xmit = &up->port.state->xmit;
504 	if (uart_circ_empty(xmit))
505 		goto ack_tx_int;
506 
507 	if (uart_tx_stopped(&up->port))
508 		goto ack_tx_int;
509 
510 	up->flags |= SUNZILOG_FLAG_TX_ACTIVE;
511 	writeb(xmit->buf[xmit->tail], &channel->data);
512 	ZSDELAY();
513 	ZS_WSYNC(channel);
514 
515 	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
516 	up->port.icount.tx++;
517 
518 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
519 		uart_write_wakeup(&up->port);
520 
521 	return;
522 
523 ack_tx_int:
524 	writeb(RES_Tx_P, &channel->control);
525 	ZSDELAY();
526 	ZS_WSYNC(channel);
527 }
528 
529 static irqreturn_t sunzilog_interrupt(int irq, void *dev_id)
530 {
531 	struct uart_sunzilog_port *up = dev_id;
532 
533 	while (up) {
534 		struct zilog_channel __iomem *channel
535 			= ZILOG_CHANNEL_FROM_PORT(&up->port);
536 		struct tty_port *port;
537 		unsigned char r3;
538 
539 		spin_lock(&up->port.lock);
540 		r3 = read_zsreg(channel, R3);
541 
542 		/* Channel A */
543 		port = NULL;
544 		if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
545 			writeb(RES_H_IUS, &channel->control);
546 			ZSDELAY();
547 			ZS_WSYNC(channel);
548 
549 			if (r3 & CHARxIP)
550 				port = sunzilog_receive_chars(up, channel);
551 			if (r3 & CHAEXT)
552 				sunzilog_status_handle(up, channel);
553 			if (r3 & CHATxIP)
554 				sunzilog_transmit_chars(up, channel);
555 		}
556 		spin_unlock(&up->port.lock);
557 
558 		if (port)
559 			tty_flip_buffer_push(port);
560 
561 		/* Channel B */
562 		up = up->next;
563 		channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
564 
565 		spin_lock(&up->port.lock);
566 		port = NULL;
567 		if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
568 			writeb(RES_H_IUS, &channel->control);
569 			ZSDELAY();
570 			ZS_WSYNC(channel);
571 
572 			if (r3 & CHBRxIP)
573 				port = sunzilog_receive_chars(up, channel);
574 			if (r3 & CHBEXT)
575 				sunzilog_status_handle(up, channel);
576 			if (r3 & CHBTxIP)
577 				sunzilog_transmit_chars(up, channel);
578 		}
579 		spin_unlock(&up->port.lock);
580 
581 		if (port)
582 			tty_flip_buffer_push(port);
583 
584 		up = up->next;
585 	}
586 
587 	return IRQ_HANDLED;
588 }
589 
590 /* A convenient way to quickly get R0 status.  The caller must _not_ hold the
591  * port lock, it is acquired here.
592  */
593 static __inline__ unsigned char sunzilog_read_channel_status(struct uart_port *port)
594 {
595 	struct zilog_channel __iomem *channel;
596 	unsigned char status;
597 
598 	channel = ZILOG_CHANNEL_FROM_PORT(port);
599 	status = readb(&channel->control);
600 	ZSDELAY();
601 
602 	return status;
603 }
604 
605 /* The port lock is not held.  */
606 static unsigned int sunzilog_tx_empty(struct uart_port *port)
607 {
608 	unsigned long flags;
609 	unsigned char status;
610 	unsigned int ret;
611 
612 	spin_lock_irqsave(&port->lock, flags);
613 
614 	status = sunzilog_read_channel_status(port);
615 
616 	spin_unlock_irqrestore(&port->lock, flags);
617 
618 	if (status & Tx_BUF_EMP)
619 		ret = TIOCSER_TEMT;
620 	else
621 		ret = 0;
622 
623 	return ret;
624 }
625 
626 /* The port lock is held and interrupts are disabled.  */
627 static unsigned int sunzilog_get_mctrl(struct uart_port *port)
628 {
629 	unsigned char status;
630 	unsigned int ret;
631 
632 	status = sunzilog_read_channel_status(port);
633 
634 	ret = 0;
635 	if (status & DCD)
636 		ret |= TIOCM_CAR;
637 	if (status & SYNC)
638 		ret |= TIOCM_DSR;
639 	if (status & CTS)
640 		ret |= TIOCM_CTS;
641 
642 	return ret;
643 }
644 
645 /* The port lock is held and interrupts are disabled.  */
646 static void sunzilog_set_mctrl(struct uart_port *port, unsigned int mctrl)
647 {
648 	struct uart_sunzilog_port *up =
649 		container_of(port, struct uart_sunzilog_port, port);
650 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
651 	unsigned char set_bits, clear_bits;
652 
653 	set_bits = clear_bits = 0;
654 
655 	if (mctrl & TIOCM_RTS)
656 		set_bits |= RTS;
657 	else
658 		clear_bits |= RTS;
659 	if (mctrl & TIOCM_DTR)
660 		set_bits |= DTR;
661 	else
662 		clear_bits |= DTR;
663 
664 	/* NOTE: Not subject to 'transmitter active' rule.  */
665 	up->curregs[R5] |= set_bits;
666 	up->curregs[R5] &= ~clear_bits;
667 	write_zsreg(channel, R5, up->curregs[R5]);
668 }
669 
670 /* The port lock is held and interrupts are disabled.  */
671 static void sunzilog_stop_tx(struct uart_port *port)
672 {
673 	struct uart_sunzilog_port *up =
674 		container_of(port, struct uart_sunzilog_port, port);
675 
676 	up->flags |= SUNZILOG_FLAG_TX_STOPPED;
677 }
678 
679 /* The port lock is held and interrupts are disabled.  */
680 static void sunzilog_start_tx(struct uart_port *port)
681 {
682 	struct uart_sunzilog_port *up =
683 		container_of(port, struct uart_sunzilog_port, port);
684 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
685 	unsigned char status;
686 
687 	up->flags |= SUNZILOG_FLAG_TX_ACTIVE;
688 	up->flags &= ~SUNZILOG_FLAG_TX_STOPPED;
689 
690 	status = readb(&channel->control);
691 	ZSDELAY();
692 
693 	/* TX busy?  Just wait for the TX done interrupt.  */
694 	if (!(status & Tx_BUF_EMP))
695 		return;
696 
697 	/* Send the first character to jump-start the TX done
698 	 * IRQ sending engine.
699 	 */
700 	if (port->x_char) {
701 		writeb(port->x_char, &channel->data);
702 		ZSDELAY();
703 		ZS_WSYNC(channel);
704 
705 		port->icount.tx++;
706 		port->x_char = 0;
707 	} else {
708 		struct circ_buf *xmit = &port->state->xmit;
709 
710 		if (uart_circ_empty(xmit))
711 			return;
712 		writeb(xmit->buf[xmit->tail], &channel->data);
713 		ZSDELAY();
714 		ZS_WSYNC(channel);
715 
716 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
717 		port->icount.tx++;
718 
719 		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
720 			uart_write_wakeup(&up->port);
721 	}
722 }
723 
724 /* The port lock is held.  */
725 static void sunzilog_stop_rx(struct uart_port *port)
726 {
727 	struct uart_sunzilog_port *up = UART_ZILOG(port);
728 	struct zilog_channel __iomem *channel;
729 
730 	if (ZS_IS_CONS(up))
731 		return;
732 
733 	channel = ZILOG_CHANNEL_FROM_PORT(port);
734 
735 	/* Disable all RX interrupts.  */
736 	up->curregs[R1] &= ~RxINT_MASK;
737 	sunzilog_maybe_update_regs(up, channel);
738 }
739 
740 /* The port lock is held.  */
741 static void sunzilog_enable_ms(struct uart_port *port)
742 {
743 	struct uart_sunzilog_port *up =
744 		container_of(port, struct uart_sunzilog_port, port);
745 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
746 	unsigned char new_reg;
747 
748 	new_reg = up->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
749 	if (new_reg != up->curregs[R15]) {
750 		up->curregs[R15] = new_reg;
751 
752 		/* NOTE: Not subject to 'transmitter active' rule.  */
753 		write_zsreg(channel, R15, up->curregs[R15] & ~WR7pEN);
754 	}
755 }
756 
757 /* The port lock is not held.  */
758 static void sunzilog_break_ctl(struct uart_port *port, int break_state)
759 {
760 	struct uart_sunzilog_port *up =
761 		container_of(port, struct uart_sunzilog_port, port);
762 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
763 	unsigned char set_bits, clear_bits, new_reg;
764 	unsigned long flags;
765 
766 	set_bits = clear_bits = 0;
767 
768 	if (break_state)
769 		set_bits |= SND_BRK;
770 	else
771 		clear_bits |= SND_BRK;
772 
773 	spin_lock_irqsave(&port->lock, flags);
774 
775 	new_reg = (up->curregs[R5] | set_bits) & ~clear_bits;
776 	if (new_reg != up->curregs[R5]) {
777 		up->curregs[R5] = new_reg;
778 
779 		/* NOTE: Not subject to 'transmitter active' rule.  */
780 		write_zsreg(channel, R5, up->curregs[R5]);
781 	}
782 
783 	spin_unlock_irqrestore(&port->lock, flags);
784 }
785 
786 static void __sunzilog_startup(struct uart_sunzilog_port *up)
787 {
788 	struct zilog_channel __iomem *channel;
789 
790 	channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
791 	up->prev_status = readb(&channel->control);
792 
793 	/* Enable receiver and transmitter.  */
794 	up->curregs[R3] |= RxENAB;
795 	up->curregs[R5] |= TxENAB;
796 
797 	up->curregs[R1] |= EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB;
798 	sunzilog_maybe_update_regs(up, channel);
799 }
800 
801 static int sunzilog_startup(struct uart_port *port)
802 {
803 	struct uart_sunzilog_port *up = UART_ZILOG(port);
804 	unsigned long flags;
805 
806 	if (ZS_IS_CONS(up))
807 		return 0;
808 
809 	spin_lock_irqsave(&port->lock, flags);
810 	__sunzilog_startup(up);
811 	spin_unlock_irqrestore(&port->lock, flags);
812 	return 0;
813 }
814 
815 /*
816  * The test for ZS_IS_CONS is explained by the following e-mail:
817  *****
818  * From: Russell King <rmk@arm.linux.org.uk>
819  * Date: Sun, 8 Dec 2002 10:18:38 +0000
820  *
821  * On Sun, Dec 08, 2002 at 02:43:36AM -0500, Pete Zaitcev wrote:
822  * > I boot my 2.5 boxes using "console=ttyS0,9600" argument,
823  * > and I noticed that something is not right with reference
824  * > counting in this case. It seems that when the console
825  * > is open by kernel initially, this is not accounted
826  * > as an open, and uart_startup is not called.
827  *
828  * That is correct.  We are unable to call uart_startup when the serial
829  * console is initialised because it may need to allocate memory (as
830  * request_irq does) and the memory allocators may not have been
831  * initialised.
832  *
833  * 1. initialise the port into a state where it can send characters in the
834  *    console write method.
835  *
836  * 2. don't do the actual hardware shutdown in your shutdown() method (but
837  *    do the normal software shutdown - ie, free irqs etc)
838  *****
839  */
840 static void sunzilog_shutdown(struct uart_port *port)
841 {
842 	struct uart_sunzilog_port *up = UART_ZILOG(port);
843 	struct zilog_channel __iomem *channel;
844 	unsigned long flags;
845 
846 	if (ZS_IS_CONS(up))
847 		return;
848 
849 	spin_lock_irqsave(&port->lock, flags);
850 
851 	channel = ZILOG_CHANNEL_FROM_PORT(port);
852 
853 	/* Disable receiver and transmitter.  */
854 	up->curregs[R3] &= ~RxENAB;
855 	up->curregs[R5] &= ~TxENAB;
856 
857 	/* Disable all interrupts and BRK assertion.  */
858 	up->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
859 	up->curregs[R5] &= ~SND_BRK;
860 	sunzilog_maybe_update_regs(up, channel);
861 
862 	spin_unlock_irqrestore(&port->lock, flags);
863 }
864 
865 /* Shared by TTY driver and serial console setup.  The port lock is held
866  * and local interrupts are disabled.
867  */
868 static void
869 sunzilog_convert_to_zs(struct uart_sunzilog_port *up, unsigned int cflag,
870 		       unsigned int iflag, int brg)
871 {
872 
873 	up->curregs[R10] = NRZ;
874 	up->curregs[R11] = TCBR | RCBR;
875 
876 	/* Program BAUD and clock source. */
877 	up->curregs[R4] &= ~XCLK_MASK;
878 	up->curregs[R4] |= X16CLK;
879 	up->curregs[R12] = brg & 0xff;
880 	up->curregs[R13] = (brg >> 8) & 0xff;
881 	up->curregs[R14] = BRSRC | BRENAB;
882 
883 	/* Character size, stop bits, and parity. */
884 	up->curregs[R3] &= ~RxN_MASK;
885 	up->curregs[R5] &= ~TxN_MASK;
886 	switch (cflag & CSIZE) {
887 	case CS5:
888 		up->curregs[R3] |= Rx5;
889 		up->curregs[R5] |= Tx5;
890 		up->parity_mask = 0x1f;
891 		break;
892 	case CS6:
893 		up->curregs[R3] |= Rx6;
894 		up->curregs[R5] |= Tx6;
895 		up->parity_mask = 0x3f;
896 		break;
897 	case CS7:
898 		up->curregs[R3] |= Rx7;
899 		up->curregs[R5] |= Tx7;
900 		up->parity_mask = 0x7f;
901 		break;
902 	case CS8:
903 	default:
904 		up->curregs[R3] |= Rx8;
905 		up->curregs[R5] |= Tx8;
906 		up->parity_mask = 0xff;
907 		break;
908 	}
909 	up->curregs[R4] &= ~0x0c;
910 	if (cflag & CSTOPB)
911 		up->curregs[R4] |= SB2;
912 	else
913 		up->curregs[R4] |= SB1;
914 	if (cflag & PARENB)
915 		up->curregs[R4] |= PAR_ENAB;
916 	else
917 		up->curregs[R4] &= ~PAR_ENAB;
918 	if (!(cflag & PARODD))
919 		up->curregs[R4] |= PAR_EVEN;
920 	else
921 		up->curregs[R4] &= ~PAR_EVEN;
922 
923 	up->port.read_status_mask = Rx_OVR;
924 	if (iflag & INPCK)
925 		up->port.read_status_mask |= CRC_ERR | PAR_ERR;
926 	if (iflag & (IGNBRK | BRKINT | PARMRK))
927 		up->port.read_status_mask |= BRK_ABRT;
928 
929 	up->port.ignore_status_mask = 0;
930 	if (iflag & IGNPAR)
931 		up->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
932 	if (iflag & IGNBRK) {
933 		up->port.ignore_status_mask |= BRK_ABRT;
934 		if (iflag & IGNPAR)
935 			up->port.ignore_status_mask |= Rx_OVR;
936 	}
937 
938 	if ((cflag & CREAD) == 0)
939 		up->port.ignore_status_mask = 0xff;
940 }
941 
942 /* The port lock is not held.  */
943 static void
944 sunzilog_set_termios(struct uart_port *port, struct ktermios *termios,
945 		     struct ktermios *old)
946 {
947 	struct uart_sunzilog_port *up =
948 		container_of(port, struct uart_sunzilog_port, port);
949 	unsigned long flags;
950 	int baud, brg;
951 
952 	baud = uart_get_baud_rate(port, termios, old, 1200, 76800);
953 
954 	spin_lock_irqsave(&up->port.lock, flags);
955 
956 	brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
957 
958 	sunzilog_convert_to_zs(up, termios->c_cflag, termios->c_iflag, brg);
959 
960 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
961 		up->flags |= SUNZILOG_FLAG_MODEM_STATUS;
962 	else
963 		up->flags &= ~SUNZILOG_FLAG_MODEM_STATUS;
964 
965 	up->cflag = termios->c_cflag;
966 
967 	sunzilog_maybe_update_regs(up, ZILOG_CHANNEL_FROM_PORT(port));
968 
969 	uart_update_timeout(port, termios->c_cflag, baud);
970 
971 	spin_unlock_irqrestore(&up->port.lock, flags);
972 }
973 
974 static const char *sunzilog_type(struct uart_port *port)
975 {
976 	struct uart_sunzilog_port *up = UART_ZILOG(port);
977 
978 	return (up->flags & SUNZILOG_FLAG_ESCC) ? "zs (ESCC)" : "zs";
979 }
980 
981 /* We do not request/release mappings of the registers here, this
982  * happens at early serial probe time.
983  */
984 static void sunzilog_release_port(struct uart_port *port)
985 {
986 }
987 
988 static int sunzilog_request_port(struct uart_port *port)
989 {
990 	return 0;
991 }
992 
993 /* These do not need to do anything interesting either.  */
994 static void sunzilog_config_port(struct uart_port *port, int flags)
995 {
996 }
997 
998 /* We do not support letting the user mess with the divisor, IRQ, etc. */
999 static int sunzilog_verify_port(struct uart_port *port, struct serial_struct *ser)
1000 {
1001 	return -EINVAL;
1002 }
1003 
1004 #ifdef CONFIG_CONSOLE_POLL
1005 static int sunzilog_get_poll_char(struct uart_port *port)
1006 {
1007 	unsigned char ch, r1;
1008 	struct uart_sunzilog_port *up =
1009 		container_of(port, struct uart_sunzilog_port, port);
1010 	struct zilog_channel __iomem *channel
1011 		= ZILOG_CHANNEL_FROM_PORT(&up->port);
1012 
1013 
1014 	r1 = read_zsreg(channel, R1);
1015 	if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
1016 		writeb(ERR_RES, &channel->control);
1017 		ZSDELAY();
1018 		ZS_WSYNC(channel);
1019 	}
1020 
1021 	ch = readb(&channel->control);
1022 	ZSDELAY();
1023 
1024 	/* This funny hack depends upon BRK_ABRT not interfering
1025 	 * with the other bits we care about in R1.
1026 	 */
1027 	if (ch & BRK_ABRT)
1028 		r1 |= BRK_ABRT;
1029 
1030 	if (!(ch & Rx_CH_AV))
1031 		return NO_POLL_CHAR;
1032 
1033 	ch = readb(&channel->data);
1034 	ZSDELAY();
1035 
1036 	ch &= up->parity_mask;
1037 	return ch;
1038 }
1039 
1040 static void sunzilog_put_poll_char(struct uart_port *port,
1041 			unsigned char ch)
1042 {
1043 	struct uart_sunzilog_port *up =
1044 		container_of(port, struct uart_sunzilog_port, port);
1045 
1046 	sunzilog_putchar(&up->port, ch);
1047 }
1048 #endif /* CONFIG_CONSOLE_POLL */
1049 
1050 static const struct uart_ops sunzilog_pops = {
1051 	.tx_empty	=	sunzilog_tx_empty,
1052 	.set_mctrl	=	sunzilog_set_mctrl,
1053 	.get_mctrl	=	sunzilog_get_mctrl,
1054 	.stop_tx	=	sunzilog_stop_tx,
1055 	.start_tx	=	sunzilog_start_tx,
1056 	.stop_rx	=	sunzilog_stop_rx,
1057 	.enable_ms	=	sunzilog_enable_ms,
1058 	.break_ctl	=	sunzilog_break_ctl,
1059 	.startup	=	sunzilog_startup,
1060 	.shutdown	=	sunzilog_shutdown,
1061 	.set_termios	=	sunzilog_set_termios,
1062 	.type		=	sunzilog_type,
1063 	.release_port	=	sunzilog_release_port,
1064 	.request_port	=	sunzilog_request_port,
1065 	.config_port	=	sunzilog_config_port,
1066 	.verify_port	=	sunzilog_verify_port,
1067 #ifdef CONFIG_CONSOLE_POLL
1068 	.poll_get_char	=	sunzilog_get_poll_char,
1069 	.poll_put_char	=	sunzilog_put_poll_char,
1070 #endif
1071 };
1072 
1073 static int uart_chip_count;
1074 static struct uart_sunzilog_port *sunzilog_port_table;
1075 static struct zilog_layout __iomem **sunzilog_chip_regs;
1076 
1077 static struct uart_sunzilog_port *sunzilog_irq_chain;
1078 
1079 static struct uart_driver sunzilog_reg = {
1080 	.owner		=	THIS_MODULE,
1081 	.driver_name	=	"sunzilog",
1082 	.dev_name	=	"ttyS",
1083 	.major		=	TTY_MAJOR,
1084 };
1085 
1086 static int __init sunzilog_alloc_tables(int num_sunzilog)
1087 {
1088 	struct uart_sunzilog_port *up;
1089 	unsigned long size;
1090 	int num_channels = num_sunzilog * 2;
1091 	int i;
1092 
1093 	size = num_channels * sizeof(struct uart_sunzilog_port);
1094 	sunzilog_port_table = kzalloc(size, GFP_KERNEL);
1095 	if (!sunzilog_port_table)
1096 		return -ENOMEM;
1097 
1098 	for (i = 0; i < num_channels; i++) {
1099 		up = &sunzilog_port_table[i];
1100 
1101 		spin_lock_init(&up->port.lock);
1102 
1103 		if (i == 0)
1104 			sunzilog_irq_chain = up;
1105 
1106 		if (i < num_channels - 1)
1107 			up->next = up + 1;
1108 		else
1109 			up->next = NULL;
1110 	}
1111 
1112 	size = num_sunzilog * sizeof(struct zilog_layout __iomem *);
1113 	sunzilog_chip_regs = kzalloc(size, GFP_KERNEL);
1114 	if (!sunzilog_chip_regs) {
1115 		kfree(sunzilog_port_table);
1116 		sunzilog_irq_chain = NULL;
1117 		return -ENOMEM;
1118 	}
1119 
1120 	return 0;
1121 }
1122 
1123 static void sunzilog_free_tables(void)
1124 {
1125 	kfree(sunzilog_port_table);
1126 	sunzilog_irq_chain = NULL;
1127 	kfree(sunzilog_chip_regs);
1128 }
1129 
1130 #define ZS_PUT_CHAR_MAX_DELAY	2000	/* 10 ms */
1131 
1132 static void sunzilog_putchar(struct uart_port *port, int ch)
1133 {
1134 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
1135 	int loops = ZS_PUT_CHAR_MAX_DELAY;
1136 
1137 	/* This is a timed polling loop so do not switch the explicit
1138 	 * udelay with ZSDELAY as that is a NOP on some platforms.  -DaveM
1139 	 */
1140 	do {
1141 		unsigned char val = readb(&channel->control);
1142 		if (val & Tx_BUF_EMP) {
1143 			ZSDELAY();
1144 			break;
1145 		}
1146 		udelay(5);
1147 	} while (--loops);
1148 
1149 	writeb(ch, &channel->data);
1150 	ZSDELAY();
1151 	ZS_WSYNC(channel);
1152 }
1153 
1154 #ifdef CONFIG_SERIO
1155 
1156 static DEFINE_SPINLOCK(sunzilog_serio_lock);
1157 
1158 static int sunzilog_serio_write(struct serio *serio, unsigned char ch)
1159 {
1160 	struct uart_sunzilog_port *up = serio->port_data;
1161 	unsigned long flags;
1162 
1163 	spin_lock_irqsave(&sunzilog_serio_lock, flags);
1164 
1165 	sunzilog_putchar(&up->port, ch);
1166 
1167 	spin_unlock_irqrestore(&sunzilog_serio_lock, flags);
1168 
1169 	return 0;
1170 }
1171 
1172 static int sunzilog_serio_open(struct serio *serio)
1173 {
1174 	struct uart_sunzilog_port *up = serio->port_data;
1175 	unsigned long flags;
1176 	int ret;
1177 
1178 	spin_lock_irqsave(&sunzilog_serio_lock, flags);
1179 	if (!up->serio_open) {
1180 		up->serio_open = 1;
1181 		ret = 0;
1182 	} else
1183 		ret = -EBUSY;
1184 	spin_unlock_irqrestore(&sunzilog_serio_lock, flags);
1185 
1186 	return ret;
1187 }
1188 
1189 static void sunzilog_serio_close(struct serio *serio)
1190 {
1191 	struct uart_sunzilog_port *up = serio->port_data;
1192 	unsigned long flags;
1193 
1194 	spin_lock_irqsave(&sunzilog_serio_lock, flags);
1195 	up->serio_open = 0;
1196 	spin_unlock_irqrestore(&sunzilog_serio_lock, flags);
1197 }
1198 
1199 #endif /* CONFIG_SERIO */
1200 
1201 #ifdef CONFIG_SERIAL_SUNZILOG_CONSOLE
1202 static void
1203 sunzilog_console_write(struct console *con, const char *s, unsigned int count)
1204 {
1205 	struct uart_sunzilog_port *up = &sunzilog_port_table[con->index];
1206 	unsigned long flags;
1207 	int locked = 1;
1208 
1209 	if (up->port.sysrq || oops_in_progress)
1210 		locked = spin_trylock_irqsave(&up->port.lock, flags);
1211 	else
1212 		spin_lock_irqsave(&up->port.lock, flags);
1213 
1214 	uart_console_write(&up->port, s, count, sunzilog_putchar);
1215 	udelay(2);
1216 
1217 	if (locked)
1218 		spin_unlock_irqrestore(&up->port.lock, flags);
1219 }
1220 
1221 static int __init sunzilog_console_setup(struct console *con, char *options)
1222 {
1223 	struct uart_sunzilog_port *up = &sunzilog_port_table[con->index];
1224 	unsigned long flags;
1225 	int baud, brg;
1226 
1227 	if (up->port.type != PORT_SUNZILOG)
1228 		return -1;
1229 
1230 	printk(KERN_INFO "Console: ttyS%d (SunZilog zs%d)\n",
1231 	       (sunzilog_reg.minor - 64) + con->index, con->index);
1232 
1233 	/* Get firmware console settings.  */
1234 	sunserial_console_termios(con, up->port.dev->of_node);
1235 
1236 	/* Firmware console speed is limited to 150-->38400 baud so
1237 	 * this hackish cflag thing is OK.
1238 	 */
1239 	switch (con->cflag & CBAUD) {
1240 	case B150: baud = 150; break;
1241 	case B300: baud = 300; break;
1242 	case B600: baud = 600; break;
1243 	case B1200: baud = 1200; break;
1244 	case B2400: baud = 2400; break;
1245 	case B4800: baud = 4800; break;
1246 	default: case B9600: baud = 9600; break;
1247 	case B19200: baud = 19200; break;
1248 	case B38400: baud = 38400; break;
1249 	}
1250 
1251 	brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
1252 
1253 	spin_lock_irqsave(&up->port.lock, flags);
1254 
1255 	up->curregs[R15] |= BRKIE;
1256 	sunzilog_convert_to_zs(up, con->cflag, 0, brg);
1257 
1258 	sunzilog_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
1259 	__sunzilog_startup(up);
1260 
1261 	spin_unlock_irqrestore(&up->port.lock, flags);
1262 
1263 	return 0;
1264 }
1265 
1266 static struct console sunzilog_console_ops = {
1267 	.name	=	"ttyS",
1268 	.write	=	sunzilog_console_write,
1269 	.device	=	uart_console_device,
1270 	.setup	=	sunzilog_console_setup,
1271 	.flags	=	CON_PRINTBUFFER,
1272 	.index	=	-1,
1273 	.data   =	&sunzilog_reg,
1274 };
1275 
1276 static inline struct console *SUNZILOG_CONSOLE(void)
1277 {
1278 	return &sunzilog_console_ops;
1279 }
1280 
1281 #else
1282 #define SUNZILOG_CONSOLE()	(NULL)
1283 #endif
1284 
1285 static void sunzilog_init_kbdms(struct uart_sunzilog_port *up)
1286 {
1287 	int baud, brg;
1288 
1289 	if (up->flags & SUNZILOG_FLAG_CONS_KEYB) {
1290 		up->cflag = B1200 | CS8 | CLOCAL | CREAD;
1291 		baud = 1200;
1292 	} else {
1293 		up->cflag = B4800 | CS8 | CLOCAL | CREAD;
1294 		baud = 4800;
1295 	}
1296 
1297 	up->curregs[R15] |= BRKIE;
1298 	brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
1299 	sunzilog_convert_to_zs(up, up->cflag, 0, brg);
1300 	sunzilog_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
1301 	__sunzilog_startup(up);
1302 }
1303 
1304 #ifdef CONFIG_SERIO
1305 static void sunzilog_register_serio(struct uart_sunzilog_port *up)
1306 {
1307 	struct serio *serio = &up->serio;
1308 
1309 	serio->port_data = up;
1310 
1311 	serio->id.type = SERIO_RS232;
1312 	if (up->flags & SUNZILOG_FLAG_CONS_KEYB) {
1313 		serio->id.proto = SERIO_SUNKBD;
1314 		strlcpy(serio->name, "zskbd", sizeof(serio->name));
1315 	} else {
1316 		serio->id.proto = SERIO_SUN;
1317 		serio->id.extra = 1;
1318 		strlcpy(serio->name, "zsms", sizeof(serio->name));
1319 	}
1320 	strlcpy(serio->phys,
1321 		((up->flags & SUNZILOG_FLAG_CONS_KEYB) ?
1322 		 "zs/serio0" : "zs/serio1"),
1323 		sizeof(serio->phys));
1324 
1325 	serio->write = sunzilog_serio_write;
1326 	serio->open = sunzilog_serio_open;
1327 	serio->close = sunzilog_serio_close;
1328 	serio->dev.parent = up->port.dev;
1329 
1330 	serio_register_port(serio);
1331 }
1332 #endif
1333 
1334 static void sunzilog_init_hw(struct uart_sunzilog_port *up)
1335 {
1336 	struct zilog_channel __iomem *channel;
1337 	unsigned long flags;
1338 	int baud, brg;
1339 
1340 	channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
1341 
1342 	spin_lock_irqsave(&up->port.lock, flags);
1343 	if (ZS_IS_CHANNEL_A(up)) {
1344 		write_zsreg(channel, R9, FHWRES);
1345 		ZSDELAY_LONG();
1346 		(void) read_zsreg(channel, R0);
1347 	}
1348 
1349 	if (up->flags & (SUNZILOG_FLAG_CONS_KEYB |
1350 			 SUNZILOG_FLAG_CONS_MOUSE)) {
1351 		up->curregs[R1] = EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB;
1352 		up->curregs[R4] = PAR_EVEN | X16CLK | SB1;
1353 		up->curregs[R3] = RxENAB | Rx8;
1354 		up->curregs[R5] = TxENAB | Tx8;
1355 		up->curregs[R6] = 0x00; /* SDLC Address */
1356 		up->curregs[R7] = 0x7E; /* SDLC Flag    */
1357 		up->curregs[R9] = NV;
1358 		up->curregs[R7p] = 0x00;
1359 		sunzilog_init_kbdms(up);
1360 		/* Only enable interrupts if an ISR handler available */
1361 		if (up->flags & SUNZILOG_FLAG_ISR_HANDLER)
1362 			up->curregs[R9] |= MIE;
1363 		write_zsreg(channel, R9, up->curregs[R9]);
1364 	} else {
1365 		/* Normal serial TTY. */
1366 		up->parity_mask = 0xff;
1367 		up->curregs[R1] = EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB;
1368 		up->curregs[R4] = PAR_EVEN | X16CLK | SB1;
1369 		up->curregs[R3] = RxENAB | Rx8;
1370 		up->curregs[R5] = TxENAB | Tx8;
1371 		up->curregs[R6] = 0x00; /* SDLC Address */
1372 		up->curregs[R7] = 0x7E; /* SDLC Flag    */
1373 		up->curregs[R9] = NV;
1374 		up->curregs[R10] = NRZ;
1375 		up->curregs[R11] = TCBR | RCBR;
1376 		baud = 9600;
1377 		brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
1378 		up->curregs[R12] = (brg & 0xff);
1379 		up->curregs[R13] = (brg >> 8) & 0xff;
1380 		up->curregs[R14] = BRSRC | BRENAB;
1381 		up->curregs[R15] = FIFOEN; /* Use FIFO if on ESCC */
1382 		up->curregs[R7p] = TxFIFO_LVL | RxFIFO_LVL;
1383 		if (__load_zsregs(channel, up->curregs)) {
1384 			up->flags |= SUNZILOG_FLAG_ESCC;
1385 		}
1386 		/* Only enable interrupts if an ISR handler available */
1387 		if (up->flags & SUNZILOG_FLAG_ISR_HANDLER)
1388 			up->curregs[R9] |= MIE;
1389 		write_zsreg(channel, R9, up->curregs[R9]);
1390 	}
1391 
1392 	spin_unlock_irqrestore(&up->port.lock, flags);
1393 
1394 #ifdef CONFIG_SERIO
1395 	if (up->flags & (SUNZILOG_FLAG_CONS_KEYB |
1396 			 SUNZILOG_FLAG_CONS_MOUSE))
1397 		sunzilog_register_serio(up);
1398 #endif
1399 }
1400 
1401 static int zilog_irq;
1402 
1403 static int zs_probe(struct platform_device *op)
1404 {
1405 	static int kbm_inst, uart_inst;
1406 	int inst;
1407 	struct uart_sunzilog_port *up;
1408 	struct zilog_layout __iomem *rp;
1409 	int keyboard_mouse = 0;
1410 	int err;
1411 
1412 	if (of_find_property(op->dev.of_node, "keyboard", NULL))
1413 		keyboard_mouse = 1;
1414 
1415 	/* uarts must come before keyboards/mice */
1416 	if (keyboard_mouse)
1417 		inst = uart_chip_count + kbm_inst;
1418 	else
1419 		inst = uart_inst;
1420 
1421 	sunzilog_chip_regs[inst] = of_ioremap(&op->resource[0], 0,
1422 					      sizeof(struct zilog_layout),
1423 					      "zs");
1424 	if (!sunzilog_chip_regs[inst])
1425 		return -ENOMEM;
1426 
1427 	rp = sunzilog_chip_regs[inst];
1428 
1429 	if (!zilog_irq)
1430 		zilog_irq = op->archdata.irqs[0];
1431 
1432 	up = &sunzilog_port_table[inst * 2];
1433 
1434 	/* Channel A */
1435 	up[0].port.mapbase = op->resource[0].start + 0x00;
1436 	up[0].port.membase = (void __iomem *) &rp->channelA;
1437 	up[0].port.iotype = UPIO_MEM;
1438 	up[0].port.irq = op->archdata.irqs[0];
1439 	up[0].port.uartclk = ZS_CLOCK;
1440 	up[0].port.fifosize = 1;
1441 	up[0].port.ops = &sunzilog_pops;
1442 	up[0].port.type = PORT_SUNZILOG;
1443 	up[0].port.flags = 0;
1444 	up[0].port.line = (inst * 2) + 0;
1445 	up[0].port.dev = &op->dev;
1446 	up[0].flags |= SUNZILOG_FLAG_IS_CHANNEL_A;
1447 	if (keyboard_mouse)
1448 		up[0].flags |= SUNZILOG_FLAG_CONS_KEYB;
1449 	sunzilog_init_hw(&up[0]);
1450 
1451 	/* Channel B */
1452 	up[1].port.mapbase = op->resource[0].start + 0x04;
1453 	up[1].port.membase = (void __iomem *) &rp->channelB;
1454 	up[1].port.iotype = UPIO_MEM;
1455 	up[1].port.irq = op->archdata.irqs[0];
1456 	up[1].port.uartclk = ZS_CLOCK;
1457 	up[1].port.fifosize = 1;
1458 	up[1].port.ops = &sunzilog_pops;
1459 	up[1].port.type = PORT_SUNZILOG;
1460 	up[1].port.flags = 0;
1461 	up[1].port.line = (inst * 2) + 1;
1462 	up[1].port.dev = &op->dev;
1463 	up[1].flags |= 0;
1464 	if (keyboard_mouse)
1465 		up[1].flags |= SUNZILOG_FLAG_CONS_MOUSE;
1466 	sunzilog_init_hw(&up[1]);
1467 
1468 	if (!keyboard_mouse) {
1469 		if (sunserial_console_match(SUNZILOG_CONSOLE(), op->dev.of_node,
1470 					    &sunzilog_reg, up[0].port.line,
1471 					    false))
1472 			up->flags |= SUNZILOG_FLAG_IS_CONS;
1473 		err = uart_add_one_port(&sunzilog_reg, &up[0].port);
1474 		if (err) {
1475 			of_iounmap(&op->resource[0],
1476 				   rp, sizeof(struct zilog_layout));
1477 			return err;
1478 		}
1479 		if (sunserial_console_match(SUNZILOG_CONSOLE(), op->dev.of_node,
1480 					    &sunzilog_reg, up[1].port.line,
1481 					    false))
1482 			up->flags |= SUNZILOG_FLAG_IS_CONS;
1483 		err = uart_add_one_port(&sunzilog_reg, &up[1].port);
1484 		if (err) {
1485 			uart_remove_one_port(&sunzilog_reg, &up[0].port);
1486 			of_iounmap(&op->resource[0],
1487 				   rp, sizeof(struct zilog_layout));
1488 			return err;
1489 		}
1490 		uart_inst++;
1491 	} else {
1492 		printk(KERN_INFO "%s: Keyboard at MMIO 0x%llx (irq = %d) "
1493 		       "is a %s\n",
1494 		       dev_name(&op->dev),
1495 		       (unsigned long long) up[0].port.mapbase,
1496 		       op->archdata.irqs[0], sunzilog_type(&up[0].port));
1497 		printk(KERN_INFO "%s: Mouse at MMIO 0x%llx (irq = %d) "
1498 		       "is a %s\n",
1499 		       dev_name(&op->dev),
1500 		       (unsigned long long) up[1].port.mapbase,
1501 		       op->archdata.irqs[0], sunzilog_type(&up[1].port));
1502 		kbm_inst++;
1503 	}
1504 
1505 	platform_set_drvdata(op, &up[0]);
1506 
1507 	return 0;
1508 }
1509 
1510 static void zs_remove_one(struct uart_sunzilog_port *up)
1511 {
1512 	if (ZS_IS_KEYB(up) || ZS_IS_MOUSE(up)) {
1513 #ifdef CONFIG_SERIO
1514 		serio_unregister_port(&up->serio);
1515 #endif
1516 	} else
1517 		uart_remove_one_port(&sunzilog_reg, &up->port);
1518 }
1519 
1520 static int zs_remove(struct platform_device *op)
1521 {
1522 	struct uart_sunzilog_port *up = platform_get_drvdata(op);
1523 	struct zilog_layout __iomem *regs;
1524 
1525 	zs_remove_one(&up[0]);
1526 	zs_remove_one(&up[1]);
1527 
1528 	regs = sunzilog_chip_regs[up[0].port.line / 2];
1529 	of_iounmap(&op->resource[0], regs, sizeof(struct zilog_layout));
1530 
1531 	return 0;
1532 }
1533 
1534 static const struct of_device_id zs_match[] = {
1535 	{
1536 		.name = "zs",
1537 	},
1538 	{},
1539 };
1540 MODULE_DEVICE_TABLE(of, zs_match);
1541 
1542 static struct platform_driver zs_driver = {
1543 	.driver = {
1544 		.name = "zs",
1545 		.of_match_table = zs_match,
1546 	},
1547 	.probe		= zs_probe,
1548 	.remove		= zs_remove,
1549 };
1550 
1551 static int __init sunzilog_init(void)
1552 {
1553 	struct device_node *dp;
1554 	int err;
1555 	int num_keybms = 0;
1556 	int num_sunzilog = 0;
1557 
1558 	for_each_node_by_name(dp, "zs") {
1559 		num_sunzilog++;
1560 		if (of_find_property(dp, "keyboard", NULL))
1561 			num_keybms++;
1562 	}
1563 
1564 	if (num_sunzilog) {
1565 		err = sunzilog_alloc_tables(num_sunzilog);
1566 		if (err)
1567 			goto out;
1568 
1569 		uart_chip_count = num_sunzilog - num_keybms;
1570 
1571 		err = sunserial_register_minors(&sunzilog_reg,
1572 						uart_chip_count * 2);
1573 		if (err)
1574 			goto out_free_tables;
1575 	}
1576 
1577 	err = platform_driver_register(&zs_driver);
1578 	if (err)
1579 		goto out_unregister_uart;
1580 
1581 	if (zilog_irq) {
1582 		struct uart_sunzilog_port *up = sunzilog_irq_chain;
1583 		err = request_irq(zilog_irq, sunzilog_interrupt, IRQF_SHARED,
1584 				  "zs", sunzilog_irq_chain);
1585 		if (err)
1586 			goto out_unregister_driver;
1587 
1588 		/* Enable Interrupts */
1589 		while (up) {
1590 			struct zilog_channel __iomem *channel;
1591 
1592 			/* printk (KERN_INFO "Enable IRQ for ZILOG Hardware %p\n", up); */
1593 			channel          = ZILOG_CHANNEL_FROM_PORT(&up->port);
1594 			up->flags       |= SUNZILOG_FLAG_ISR_HANDLER;
1595 			up->curregs[R9] |= MIE;
1596 			write_zsreg(channel, R9, up->curregs[R9]);
1597 			up = up->next;
1598 		}
1599 	}
1600 
1601 out:
1602 	return err;
1603 
1604 out_unregister_driver:
1605 	platform_driver_unregister(&zs_driver);
1606 
1607 out_unregister_uart:
1608 	if (num_sunzilog) {
1609 		sunserial_unregister_minors(&sunzilog_reg, num_sunzilog);
1610 		sunzilog_reg.cons = NULL;
1611 	}
1612 
1613 out_free_tables:
1614 	sunzilog_free_tables();
1615 	goto out;
1616 }
1617 
1618 static void __exit sunzilog_exit(void)
1619 {
1620 	platform_driver_unregister(&zs_driver);
1621 
1622 	if (zilog_irq) {
1623 		struct uart_sunzilog_port *up = sunzilog_irq_chain;
1624 
1625 		/* Disable Interrupts */
1626 		while (up) {
1627 			struct zilog_channel __iomem *channel;
1628 
1629 			/* printk (KERN_INFO "Disable IRQ for ZILOG Hardware %p\n", up); */
1630 			channel          = ZILOG_CHANNEL_FROM_PORT(&up->port);
1631 			up->flags       &= ~SUNZILOG_FLAG_ISR_HANDLER;
1632 			up->curregs[R9] &= ~MIE;
1633 			write_zsreg(channel, R9, up->curregs[R9]);
1634 			up = up->next;
1635 		}
1636 
1637 		free_irq(zilog_irq, sunzilog_irq_chain);
1638 		zilog_irq = 0;
1639 	}
1640 
1641 	if (sunzilog_reg.nr) {
1642 		sunserial_unregister_minors(&sunzilog_reg, sunzilog_reg.nr);
1643 		sunzilog_free_tables();
1644 	}
1645 }
1646 
1647 module_init(sunzilog_init);
1648 module_exit(sunzilog_exit);
1649 
1650 MODULE_AUTHOR("David S. Miller");
1651 MODULE_DESCRIPTION("Sun Zilog serial port driver");
1652 MODULE_VERSION("2.0");
1653 MODULE_LICENSE("GPL");
1654