xref: /openbmc/linux/drivers/tty/serial/sunzilog.c (revision e7f127b2)
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 <linux/io.h>
39 #include <asm/irq.h>
40 #include <asm/prom.h>
41 #include <asm/setup.h>
42 
43 #include <linux/serial_core.h>
44 #include <linux/sunserialcore.h>
45 
46 #include "sunzilog.h"
47 
48 /* On 32-bit sparcs we need to delay after register accesses
49  * to accommodate sun4 systems, but we do not need to flush writes.
50  * On 64-bit sparc we only need to flush single writes to ensure
51  * completion.
52  */
53 #ifndef CONFIG_SPARC64
54 #define ZSDELAY()		udelay(5)
55 #define ZSDELAY_LONG()		udelay(20)
56 #define ZS_WSYNC(channel)	do { } while (0)
57 #else
58 #define ZSDELAY()
59 #define ZSDELAY_LONG()
60 #define ZS_WSYNC(__channel) \
61 	readb(&((__channel)->control))
62 #endif
63 
64 #define ZS_CLOCK		4915200 /* Zilog input clock rate. */
65 #define ZS_CLOCK_DIVISOR	16      /* Divisor this driver uses. */
66 
67 /*
68  * We wrap our port structure around the generic uart_port.
69  */
70 struct uart_sunzilog_port {
71 	struct uart_port		port;
72 
73 	/* IRQ servicing chain.  */
74 	struct uart_sunzilog_port	*next;
75 
76 	/* Current values of Zilog write registers.  */
77 	unsigned char			curregs[NUM_ZSREGS];
78 
79 	unsigned int			flags;
80 #define SUNZILOG_FLAG_CONS_KEYB		0x00000001
81 #define SUNZILOG_FLAG_CONS_MOUSE	0x00000002
82 #define SUNZILOG_FLAG_IS_CONS		0x00000004
83 #define SUNZILOG_FLAG_IS_KGDB		0x00000008
84 #define SUNZILOG_FLAG_MODEM_STATUS	0x00000010
85 #define SUNZILOG_FLAG_IS_CHANNEL_A	0x00000020
86 #define SUNZILOG_FLAG_REGS_HELD		0x00000040
87 #define SUNZILOG_FLAG_TX_STOPPED	0x00000080
88 #define SUNZILOG_FLAG_TX_ACTIVE		0x00000100
89 #define SUNZILOG_FLAG_ESCC		0x00000200
90 #define SUNZILOG_FLAG_ISR_HANDLER	0x00000400
91 
92 	unsigned int cflag;
93 
94 	unsigned char			parity_mask;
95 	unsigned char			prev_status;
96 
97 #ifdef CONFIG_SERIO
98 	struct serio			serio;
99 	int				serio_open;
100 #endif
101 };
102 
103 static void sunzilog_putchar(struct uart_port *port, int ch);
104 
105 #define ZILOG_CHANNEL_FROM_PORT(PORT)	((struct zilog_channel __iomem *)((PORT)->membase))
106 #define UART_ZILOG(PORT)		((struct uart_sunzilog_port *)(PORT))
107 
108 #define ZS_IS_KEYB(UP)	((UP)->flags & SUNZILOG_FLAG_CONS_KEYB)
109 #define ZS_IS_MOUSE(UP)	((UP)->flags & SUNZILOG_FLAG_CONS_MOUSE)
110 #define ZS_IS_CONS(UP)	((UP)->flags & SUNZILOG_FLAG_IS_CONS)
111 #define ZS_IS_KGDB(UP)	((UP)->flags & SUNZILOG_FLAG_IS_KGDB)
112 #define ZS_WANTS_MODEM_STATUS(UP)	((UP)->flags & SUNZILOG_FLAG_MODEM_STATUS)
113 #define ZS_IS_CHANNEL_A(UP)	((UP)->flags & SUNZILOG_FLAG_IS_CHANNEL_A)
114 #define ZS_REGS_HELD(UP)	((UP)->flags & SUNZILOG_FLAG_REGS_HELD)
115 #define ZS_TX_STOPPED(UP)	((UP)->flags & SUNZILOG_FLAG_TX_STOPPED)
116 #define ZS_TX_ACTIVE(UP)	((UP)->flags & SUNZILOG_FLAG_TX_ACTIVE)
117 
118 /* Reading and writing Zilog8530 registers.  The delays are to make this
119  * driver work on the Sun4 which needs a settling delay after each chip
120  * register access, other machines handle this in hardware via auxiliary
121  * flip-flops which implement the settle time we do in software.
122  *
123  * The port lock must be held and local IRQs must be disabled
124  * when {read,write}_zsreg is invoked.
125  */
126 static unsigned char read_zsreg(struct zilog_channel __iomem *channel,
127 				unsigned char reg)
128 {
129 	unsigned char retval;
130 
131 	writeb(reg, &channel->control);
132 	ZSDELAY();
133 	retval = readb(&channel->control);
134 	ZSDELAY();
135 
136 	return retval;
137 }
138 
139 static void write_zsreg(struct zilog_channel __iomem *channel,
140 			unsigned char reg, unsigned char value)
141 {
142 	writeb(reg, &channel->control);
143 	ZSDELAY();
144 	writeb(value, &channel->control);
145 	ZSDELAY();
146 }
147 
148 static void sunzilog_clear_fifo(struct zilog_channel __iomem *channel)
149 {
150 	int i;
151 
152 	for (i = 0; i < 32; i++) {
153 		unsigned char regval;
154 
155 		regval = readb(&channel->control);
156 		ZSDELAY();
157 		if (regval & Rx_CH_AV)
158 			break;
159 
160 		regval = read_zsreg(channel, R1);
161 		readb(&channel->data);
162 		ZSDELAY();
163 
164 		if (regval & (PAR_ERR | Rx_OVR | CRC_ERR)) {
165 			writeb(ERR_RES, &channel->control);
166 			ZSDELAY();
167 			ZS_WSYNC(channel);
168 		}
169 	}
170 }
171 
172 /* This function must only be called when the TX is not busy.  The UART
173  * port lock must be held and local interrupts disabled.
174  */
175 static int __load_zsregs(struct zilog_channel __iomem *channel, unsigned char *regs)
176 {
177 	int i;
178 	int escc;
179 	unsigned char r15;
180 
181 	/* Let pending transmits finish.  */
182 	for (i = 0; i < 1000; i++) {
183 		unsigned char stat = read_zsreg(channel, R1);
184 		if (stat & ALL_SNT)
185 			break;
186 		udelay(100);
187 	}
188 
189 	writeb(ERR_RES, &channel->control);
190 	ZSDELAY();
191 	ZS_WSYNC(channel);
192 
193 	sunzilog_clear_fifo(channel);
194 
195 	/* Disable all interrupts.  */
196 	write_zsreg(channel, R1,
197 		    regs[R1] & ~(RxINT_MASK | TxINT_ENAB | EXT_INT_ENAB));
198 
199 	/* Set parity, sync config, stop bits, and clock divisor.  */
200 	write_zsreg(channel, R4, regs[R4]);
201 
202 	/* Set misc. TX/RX control bits.  */
203 	write_zsreg(channel, R10, regs[R10]);
204 
205 	/* Set TX/RX controls sans the enable bits.  */
206 	write_zsreg(channel, R3, regs[R3] & ~RxENAB);
207 	write_zsreg(channel, R5, regs[R5] & ~TxENAB);
208 
209 	/* Synchronous mode config.  */
210 	write_zsreg(channel, R6, regs[R6]);
211 	write_zsreg(channel, R7, regs[R7]);
212 
213 	/* Don't mess with the interrupt vector (R2, unused by us) and
214 	 * master interrupt control (R9).  We make sure this is setup
215 	 * properly at probe time then never touch it again.
216 	 */
217 
218 	/* Disable baud generator.  */
219 	write_zsreg(channel, R14, regs[R14] & ~BRENAB);
220 
221 	/* Clock mode control.  */
222 	write_zsreg(channel, R11, regs[R11]);
223 
224 	/* Lower and upper byte of baud rate generator divisor.  */
225 	write_zsreg(channel, R12, regs[R12]);
226 	write_zsreg(channel, R13, regs[R13]);
227 
228 	/* Now rewrite R14, with BRENAB (if set).  */
229 	write_zsreg(channel, R14, regs[R14]);
230 
231 	/* External status interrupt control.  */
232 	write_zsreg(channel, R15, (regs[R15] | WR7pEN) & ~FIFOEN);
233 
234 	/* ESCC Extension Register */
235 	r15 = read_zsreg(channel, R15);
236 	if (r15 & 0x01)	{
237 		write_zsreg(channel, R7,  regs[R7p]);
238 
239 		/* External status interrupt and FIFO control.  */
240 		write_zsreg(channel, R15, regs[R15] & ~WR7pEN);
241 		escc = 1;
242 	} else {
243 		 /* Clear FIFO bit case it is an issue */
244 		regs[R15] &= ~FIFOEN;
245 		escc = 0;
246 	}
247 
248 	/* Reset external status interrupts.  */
249 	write_zsreg(channel, R0, RES_EXT_INT); /* First Latch  */
250 	write_zsreg(channel, R0, RES_EXT_INT); /* Second Latch */
251 
252 	/* Rewrite R3/R5, this time without enables masked.  */
253 	write_zsreg(channel, R3, regs[R3]);
254 	write_zsreg(channel, R5, regs[R5]);
255 
256 	/* Rewrite R1, this time without IRQ enabled masked.  */
257 	write_zsreg(channel, R1, regs[R1]);
258 
259 	return escc;
260 }
261 
262 /* Reprogram the Zilog channel HW registers with the copies found in the
263  * software state struct.  If the transmitter is busy, we defer this update
264  * until the next TX complete interrupt.  Else, we do it right now.
265  *
266  * The UART port lock must be held and local interrupts disabled.
267  */
268 static void sunzilog_maybe_update_regs(struct uart_sunzilog_port *up,
269 				       struct zilog_channel __iomem *channel)
270 {
271 	if (!ZS_REGS_HELD(up)) {
272 		if (ZS_TX_ACTIVE(up)) {
273 			up->flags |= SUNZILOG_FLAG_REGS_HELD;
274 		} else {
275 			__load_zsregs(channel, up->curregs);
276 		}
277 	}
278 }
279 
280 static void sunzilog_change_mouse_baud(struct uart_sunzilog_port *up)
281 {
282 	unsigned int cur_cflag = up->cflag;
283 	int brg, new_baud;
284 
285 	up->cflag &= ~CBAUD;
286 	up->cflag |= suncore_mouse_baud_cflag_next(cur_cflag, &new_baud);
287 
288 	brg = BPS_TO_BRG(new_baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
289 	up->curregs[R12] = (brg & 0xff);
290 	up->curregs[R13] = (brg >> 8) & 0xff;
291 	sunzilog_maybe_update_regs(up, ZILOG_CHANNEL_FROM_PORT(&up->port));
292 }
293 
294 static void sunzilog_kbdms_receive_chars(struct uart_sunzilog_port *up,
295 					 unsigned char ch, int is_break)
296 {
297 	if (ZS_IS_KEYB(up)) {
298 		/* Stop-A is handled by drivers/char/keyboard.c now. */
299 #ifdef CONFIG_SERIO
300 		if (up->serio_open)
301 			serio_interrupt(&up->serio, ch, 0);
302 #endif
303 	} else if (ZS_IS_MOUSE(up)) {
304 		int ret = suncore_mouse_baud_detection(ch, is_break);
305 
306 		switch (ret) {
307 		case 2:
308 			sunzilog_change_mouse_baud(up);
309 			fallthrough;
310 		case 1:
311 			break;
312 
313 		case 0:
314 #ifdef CONFIG_SERIO
315 			if (up->serio_open)
316 				serio_interrupt(&up->serio, ch, 0);
317 #endif
318 			break;
319 		}
320 	}
321 }
322 
323 static struct tty_port *
324 sunzilog_receive_chars(struct uart_sunzilog_port *up,
325 		       struct zilog_channel __iomem *channel)
326 {
327 	struct tty_port *port = NULL;
328 	unsigned char ch, r1, flag;
329 
330 	if (up->port.state != NULL)		/* Unopened serial console */
331 		port = &up->port.state->port;
332 
333 	for (;;) {
334 
335 		r1 = read_zsreg(channel, R1);
336 		if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
337 			writeb(ERR_RES, &channel->control);
338 			ZSDELAY();
339 			ZS_WSYNC(channel);
340 		}
341 
342 		ch = readb(&channel->control);
343 		ZSDELAY();
344 
345 		/* This funny hack depends upon BRK_ABRT not interfering
346 		 * with the other bits we care about in R1.
347 		 */
348 		if (ch & BRK_ABRT)
349 			r1 |= BRK_ABRT;
350 
351 		if (!(ch & Rx_CH_AV))
352 			break;
353 
354 		ch = readb(&channel->data);
355 		ZSDELAY();
356 
357 		ch &= up->parity_mask;
358 
359 		if (unlikely(ZS_IS_KEYB(up)) || unlikely(ZS_IS_MOUSE(up))) {
360 			sunzilog_kbdms_receive_chars(up, ch, 0);
361 			continue;
362 		}
363 
364 		/* A real serial line, record the character and status.  */
365 		flag = TTY_NORMAL;
366 		up->port.icount.rx++;
367 		if (r1 & (BRK_ABRT | PAR_ERR | Rx_OVR | CRC_ERR)) {
368 			if (r1 & BRK_ABRT) {
369 				r1 &= ~(PAR_ERR | CRC_ERR);
370 				up->port.icount.brk++;
371 				if (uart_handle_break(&up->port))
372 					continue;
373 			}
374 			else if (r1 & PAR_ERR)
375 				up->port.icount.parity++;
376 			else if (r1 & CRC_ERR)
377 				up->port.icount.frame++;
378 			if (r1 & Rx_OVR)
379 				up->port.icount.overrun++;
380 			r1 &= up->port.read_status_mask;
381 			if (r1 & BRK_ABRT)
382 				flag = TTY_BREAK;
383 			else if (r1 & PAR_ERR)
384 				flag = TTY_PARITY;
385 			else if (r1 & CRC_ERR)
386 				flag = TTY_FRAME;
387 		}
388 		if (uart_handle_sysrq_char(&up->port, ch) || !port)
389 			continue;
390 
391 		if (up->port.ignore_status_mask == 0xff ||
392 		    (r1 & up->port.ignore_status_mask) == 0) {
393 		    	tty_insert_flip_char(port, ch, flag);
394 		}
395 		if (r1 & Rx_OVR)
396 			tty_insert_flip_char(port, 0, TTY_OVERRUN);
397 	}
398 
399 	return port;
400 }
401 
402 static void sunzilog_status_handle(struct uart_sunzilog_port *up,
403 				   struct zilog_channel __iomem *channel)
404 {
405 	unsigned char status;
406 
407 	status = readb(&channel->control);
408 	ZSDELAY();
409 
410 	writeb(RES_EXT_INT, &channel->control);
411 	ZSDELAY();
412 	ZS_WSYNC(channel);
413 
414 	if (status & BRK_ABRT) {
415 		if (ZS_IS_MOUSE(up))
416 			sunzilog_kbdms_receive_chars(up, 0, 1);
417 		if (ZS_IS_CONS(up)) {
418 			/* Wait for BREAK to deassert to avoid potentially
419 			 * confusing the PROM.
420 			 */
421 			while (1) {
422 				status = readb(&channel->control);
423 				ZSDELAY();
424 				if (!(status & BRK_ABRT))
425 					break;
426 			}
427 			sun_do_break();
428 			return;
429 		}
430 	}
431 
432 	if (ZS_WANTS_MODEM_STATUS(up)) {
433 		if (status & SYNC)
434 			up->port.icount.dsr++;
435 
436 		/* The Zilog just gives us an interrupt when DCD/CTS/etc. change.
437 		 * But it does not tell us which bit has changed, we have to keep
438 		 * track of this ourselves.
439 		 */
440 		if ((status ^ up->prev_status) ^ DCD)
441 			uart_handle_dcd_change(&up->port,
442 					       (status & DCD));
443 		if ((status ^ up->prev_status) ^ CTS)
444 			uart_handle_cts_change(&up->port,
445 					       (status & CTS));
446 
447 		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
448 	}
449 
450 	up->prev_status = status;
451 }
452 
453 static void sunzilog_transmit_chars(struct uart_sunzilog_port *up,
454 				    struct zilog_channel __iomem *channel)
455 {
456 	struct circ_buf *xmit;
457 
458 	if (ZS_IS_CONS(up)) {
459 		unsigned char status = readb(&channel->control);
460 		ZSDELAY();
461 
462 		/* TX still busy?  Just wait for the next TX done interrupt.
463 		 *
464 		 * It can occur because of how we do serial console writes.  It would
465 		 * be nice to transmit console writes just like we normally would for
466 		 * a TTY line. (ie. buffered and TX interrupt driven).  That is not
467 		 * easy because console writes cannot sleep.  One solution might be
468 		 * to poll on enough port->xmit space becoming free.  -DaveM
469 		 */
470 		if (!(status & Tx_BUF_EMP))
471 			return;
472 	}
473 
474 	up->flags &= ~SUNZILOG_FLAG_TX_ACTIVE;
475 
476 	if (ZS_REGS_HELD(up)) {
477 		__load_zsregs(channel, up->curregs);
478 		up->flags &= ~SUNZILOG_FLAG_REGS_HELD;
479 	}
480 
481 	if (ZS_TX_STOPPED(up)) {
482 		up->flags &= ~SUNZILOG_FLAG_TX_STOPPED;
483 		goto ack_tx_int;
484 	}
485 
486 	if (up->port.x_char) {
487 		up->flags |= SUNZILOG_FLAG_TX_ACTIVE;
488 		writeb(up->port.x_char, &channel->data);
489 		ZSDELAY();
490 		ZS_WSYNC(channel);
491 
492 		up->port.icount.tx++;
493 		up->port.x_char = 0;
494 		return;
495 	}
496 
497 	if (up->port.state == NULL)
498 		goto ack_tx_int;
499 	xmit = &up->port.state->xmit;
500 	if (uart_circ_empty(xmit))
501 		goto ack_tx_int;
502 
503 	if (uart_tx_stopped(&up->port))
504 		goto ack_tx_int;
505 
506 	up->flags |= SUNZILOG_FLAG_TX_ACTIVE;
507 	writeb(xmit->buf[xmit->tail], &channel->data);
508 	ZSDELAY();
509 	ZS_WSYNC(channel);
510 
511 	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
512 	up->port.icount.tx++;
513 
514 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
515 		uart_write_wakeup(&up->port);
516 
517 	return;
518 
519 ack_tx_int:
520 	writeb(RES_Tx_P, &channel->control);
521 	ZSDELAY();
522 	ZS_WSYNC(channel);
523 }
524 
525 static irqreturn_t sunzilog_interrupt(int irq, void *dev_id)
526 {
527 	struct uart_sunzilog_port *up = dev_id;
528 
529 	while (up) {
530 		struct zilog_channel __iomem *channel
531 			= ZILOG_CHANNEL_FROM_PORT(&up->port);
532 		struct tty_port *port;
533 		unsigned char r3;
534 
535 		spin_lock(&up->port.lock);
536 		r3 = read_zsreg(channel, R3);
537 
538 		/* Channel A */
539 		port = NULL;
540 		if (r3 & (CHAEXT | CHATxIP | CHARxIP)) {
541 			writeb(RES_H_IUS, &channel->control);
542 			ZSDELAY();
543 			ZS_WSYNC(channel);
544 
545 			if (r3 & CHARxIP)
546 				port = sunzilog_receive_chars(up, channel);
547 			if (r3 & CHAEXT)
548 				sunzilog_status_handle(up, channel);
549 			if (r3 & CHATxIP)
550 				sunzilog_transmit_chars(up, channel);
551 		}
552 		spin_unlock(&up->port.lock);
553 
554 		if (port)
555 			tty_flip_buffer_push(port);
556 
557 		/* Channel B */
558 		up = up->next;
559 		channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
560 
561 		spin_lock(&up->port.lock);
562 		port = NULL;
563 		if (r3 & (CHBEXT | CHBTxIP | CHBRxIP)) {
564 			writeb(RES_H_IUS, &channel->control);
565 			ZSDELAY();
566 			ZS_WSYNC(channel);
567 
568 			if (r3 & CHBRxIP)
569 				port = sunzilog_receive_chars(up, channel);
570 			if (r3 & CHBEXT)
571 				sunzilog_status_handle(up, channel);
572 			if (r3 & CHBTxIP)
573 				sunzilog_transmit_chars(up, channel);
574 		}
575 		spin_unlock(&up->port.lock);
576 
577 		if (port)
578 			tty_flip_buffer_push(port);
579 
580 		up = up->next;
581 	}
582 
583 	return IRQ_HANDLED;
584 }
585 
586 /* A convenient way to quickly get R0 status.  The caller must _not_ hold the
587  * port lock, it is acquired here.
588  */
589 static __inline__ unsigned char sunzilog_read_channel_status(struct uart_port *port)
590 {
591 	struct zilog_channel __iomem *channel;
592 	unsigned char status;
593 
594 	channel = ZILOG_CHANNEL_FROM_PORT(port);
595 	status = readb(&channel->control);
596 	ZSDELAY();
597 
598 	return status;
599 }
600 
601 /* The port lock is not held.  */
602 static unsigned int sunzilog_tx_empty(struct uart_port *port)
603 {
604 	unsigned long flags;
605 	unsigned char status;
606 	unsigned int ret;
607 
608 	spin_lock_irqsave(&port->lock, flags);
609 
610 	status = sunzilog_read_channel_status(port);
611 
612 	spin_unlock_irqrestore(&port->lock, flags);
613 
614 	if (status & Tx_BUF_EMP)
615 		ret = TIOCSER_TEMT;
616 	else
617 		ret = 0;
618 
619 	return ret;
620 }
621 
622 /* The port lock is held and interrupts are disabled.  */
623 static unsigned int sunzilog_get_mctrl(struct uart_port *port)
624 {
625 	unsigned char status;
626 	unsigned int ret;
627 
628 	status = sunzilog_read_channel_status(port);
629 
630 	ret = 0;
631 	if (status & DCD)
632 		ret |= TIOCM_CAR;
633 	if (status & SYNC)
634 		ret |= TIOCM_DSR;
635 	if (status & CTS)
636 		ret |= TIOCM_CTS;
637 
638 	return ret;
639 }
640 
641 /* The port lock is held and interrupts are disabled.  */
642 static void sunzilog_set_mctrl(struct uart_port *port, unsigned int mctrl)
643 {
644 	struct uart_sunzilog_port *up =
645 		container_of(port, struct uart_sunzilog_port, port);
646 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
647 	unsigned char set_bits, clear_bits;
648 
649 	set_bits = clear_bits = 0;
650 
651 	if (mctrl & TIOCM_RTS)
652 		set_bits |= RTS;
653 	else
654 		clear_bits |= RTS;
655 	if (mctrl & TIOCM_DTR)
656 		set_bits |= DTR;
657 	else
658 		clear_bits |= DTR;
659 
660 	/* NOTE: Not subject to 'transmitter active' rule.  */
661 	up->curregs[R5] |= set_bits;
662 	up->curregs[R5] &= ~clear_bits;
663 	write_zsreg(channel, R5, up->curregs[R5]);
664 }
665 
666 /* The port lock is held and interrupts are disabled.  */
667 static void sunzilog_stop_tx(struct uart_port *port)
668 {
669 	struct uart_sunzilog_port *up =
670 		container_of(port, struct uart_sunzilog_port, port);
671 
672 	up->flags |= SUNZILOG_FLAG_TX_STOPPED;
673 }
674 
675 /* The port lock is held and interrupts are disabled.  */
676 static void sunzilog_start_tx(struct uart_port *port)
677 {
678 	struct uart_sunzilog_port *up =
679 		container_of(port, struct uart_sunzilog_port, port);
680 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
681 	unsigned char status;
682 
683 	up->flags |= SUNZILOG_FLAG_TX_ACTIVE;
684 	up->flags &= ~SUNZILOG_FLAG_TX_STOPPED;
685 
686 	status = readb(&channel->control);
687 	ZSDELAY();
688 
689 	/* TX busy?  Just wait for the TX done interrupt.  */
690 	if (!(status & Tx_BUF_EMP))
691 		return;
692 
693 	/* Send the first character to jump-start the TX done
694 	 * IRQ sending engine.
695 	 */
696 	if (port->x_char) {
697 		writeb(port->x_char, &channel->data);
698 		ZSDELAY();
699 		ZS_WSYNC(channel);
700 
701 		port->icount.tx++;
702 		port->x_char = 0;
703 	} else {
704 		struct circ_buf *xmit = &port->state->xmit;
705 
706 		if (uart_circ_empty(xmit))
707 			return;
708 		writeb(xmit->buf[xmit->tail], &channel->data);
709 		ZSDELAY();
710 		ZS_WSYNC(channel);
711 
712 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
713 		port->icount.tx++;
714 
715 		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
716 			uart_write_wakeup(&up->port);
717 	}
718 }
719 
720 /* The port lock is held.  */
721 static void sunzilog_stop_rx(struct uart_port *port)
722 {
723 	struct uart_sunzilog_port *up = UART_ZILOG(port);
724 	struct zilog_channel __iomem *channel;
725 
726 	if (ZS_IS_CONS(up))
727 		return;
728 
729 	channel = ZILOG_CHANNEL_FROM_PORT(port);
730 
731 	/* Disable all RX interrupts.  */
732 	up->curregs[R1] &= ~RxINT_MASK;
733 	sunzilog_maybe_update_regs(up, channel);
734 }
735 
736 /* The port lock is held.  */
737 static void sunzilog_enable_ms(struct uart_port *port)
738 {
739 	struct uart_sunzilog_port *up =
740 		container_of(port, struct uart_sunzilog_port, port);
741 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
742 	unsigned char new_reg;
743 
744 	new_reg = up->curregs[R15] | (DCDIE | SYNCIE | CTSIE);
745 	if (new_reg != up->curregs[R15]) {
746 		up->curregs[R15] = new_reg;
747 
748 		/* NOTE: Not subject to 'transmitter active' rule.  */
749 		write_zsreg(channel, R15, up->curregs[R15] & ~WR7pEN);
750 	}
751 }
752 
753 /* The port lock is not held.  */
754 static void sunzilog_break_ctl(struct uart_port *port, int break_state)
755 {
756 	struct uart_sunzilog_port *up =
757 		container_of(port, struct uart_sunzilog_port, port);
758 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
759 	unsigned char set_bits, clear_bits, new_reg;
760 	unsigned long flags;
761 
762 	set_bits = clear_bits = 0;
763 
764 	if (break_state)
765 		set_bits |= SND_BRK;
766 	else
767 		clear_bits |= SND_BRK;
768 
769 	spin_lock_irqsave(&port->lock, flags);
770 
771 	new_reg = (up->curregs[R5] | set_bits) & ~clear_bits;
772 	if (new_reg != up->curregs[R5]) {
773 		up->curregs[R5] = new_reg;
774 
775 		/* NOTE: Not subject to 'transmitter active' rule.  */
776 		write_zsreg(channel, R5, up->curregs[R5]);
777 	}
778 
779 	spin_unlock_irqrestore(&port->lock, flags);
780 }
781 
782 static void __sunzilog_startup(struct uart_sunzilog_port *up)
783 {
784 	struct zilog_channel __iomem *channel;
785 
786 	channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
787 	up->prev_status = readb(&channel->control);
788 
789 	/* Enable receiver and transmitter.  */
790 	up->curregs[R3] |= RxENAB;
791 	up->curregs[R5] |= TxENAB;
792 
793 	up->curregs[R1] |= EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB;
794 	sunzilog_maybe_update_regs(up, channel);
795 }
796 
797 static int sunzilog_startup(struct uart_port *port)
798 {
799 	struct uart_sunzilog_port *up = UART_ZILOG(port);
800 	unsigned long flags;
801 
802 	if (ZS_IS_CONS(up))
803 		return 0;
804 
805 	spin_lock_irqsave(&port->lock, flags);
806 	__sunzilog_startup(up);
807 	spin_unlock_irqrestore(&port->lock, flags);
808 	return 0;
809 }
810 
811 /*
812  * The test for ZS_IS_CONS is explained by the following e-mail:
813  *****
814  * From: Russell King <rmk@arm.linux.org.uk>
815  * Date: Sun, 8 Dec 2002 10:18:38 +0000
816  *
817  * On Sun, Dec 08, 2002 at 02:43:36AM -0500, Pete Zaitcev wrote:
818  * > I boot my 2.5 boxes using "console=ttyS0,9600" argument,
819  * > and I noticed that something is not right with reference
820  * > counting in this case. It seems that when the console
821  * > is open by kernel initially, this is not accounted
822  * > as an open, and uart_startup is not called.
823  *
824  * That is correct.  We are unable to call uart_startup when the serial
825  * console is initialised because it may need to allocate memory (as
826  * request_irq does) and the memory allocators may not have been
827  * initialised.
828  *
829  * 1. initialise the port into a state where it can send characters in the
830  *    console write method.
831  *
832  * 2. don't do the actual hardware shutdown in your shutdown() method (but
833  *    do the normal software shutdown - ie, free irqs etc)
834  *****
835  */
836 static void sunzilog_shutdown(struct uart_port *port)
837 {
838 	struct uart_sunzilog_port *up = UART_ZILOG(port);
839 	struct zilog_channel __iomem *channel;
840 	unsigned long flags;
841 
842 	if (ZS_IS_CONS(up))
843 		return;
844 
845 	spin_lock_irqsave(&port->lock, flags);
846 
847 	channel = ZILOG_CHANNEL_FROM_PORT(port);
848 
849 	/* Disable receiver and transmitter.  */
850 	up->curregs[R3] &= ~RxENAB;
851 	up->curregs[R5] &= ~TxENAB;
852 
853 	/* Disable all interrupts and BRK assertion.  */
854 	up->curregs[R1] &= ~(EXT_INT_ENAB | TxINT_ENAB | RxINT_MASK);
855 	up->curregs[R5] &= ~SND_BRK;
856 	sunzilog_maybe_update_regs(up, channel);
857 
858 	spin_unlock_irqrestore(&port->lock, flags);
859 }
860 
861 /* Shared by TTY driver and serial console setup.  The port lock is held
862  * and local interrupts are disabled.
863  */
864 static void
865 sunzilog_convert_to_zs(struct uart_sunzilog_port *up, unsigned int cflag,
866 		       unsigned int iflag, int brg)
867 {
868 
869 	up->curregs[R10] = NRZ;
870 	up->curregs[R11] = TCBR | RCBR;
871 
872 	/* Program BAUD and clock source. */
873 	up->curregs[R4] &= ~XCLK_MASK;
874 	up->curregs[R4] |= X16CLK;
875 	up->curregs[R12] = brg & 0xff;
876 	up->curregs[R13] = (brg >> 8) & 0xff;
877 	up->curregs[R14] = BRSRC | BRENAB;
878 
879 	/* Character size, stop bits, and parity. */
880 	up->curregs[R3] &= ~RxN_MASK;
881 	up->curregs[R5] &= ~TxN_MASK;
882 	switch (cflag & CSIZE) {
883 	case CS5:
884 		up->curregs[R3] |= Rx5;
885 		up->curregs[R5] |= Tx5;
886 		up->parity_mask = 0x1f;
887 		break;
888 	case CS6:
889 		up->curregs[R3] |= Rx6;
890 		up->curregs[R5] |= Tx6;
891 		up->parity_mask = 0x3f;
892 		break;
893 	case CS7:
894 		up->curregs[R3] |= Rx7;
895 		up->curregs[R5] |= Tx7;
896 		up->parity_mask = 0x7f;
897 		break;
898 	case CS8:
899 	default:
900 		up->curregs[R3] |= Rx8;
901 		up->curregs[R5] |= Tx8;
902 		up->parity_mask = 0xff;
903 		break;
904 	}
905 	up->curregs[R4] &= ~0x0c;
906 	if (cflag & CSTOPB)
907 		up->curregs[R4] |= SB2;
908 	else
909 		up->curregs[R4] |= SB1;
910 	if (cflag & PARENB)
911 		up->curregs[R4] |= PAR_ENAB;
912 	else
913 		up->curregs[R4] &= ~PAR_ENAB;
914 	if (!(cflag & PARODD))
915 		up->curregs[R4] |= PAR_EVEN;
916 	else
917 		up->curregs[R4] &= ~PAR_EVEN;
918 
919 	up->port.read_status_mask = Rx_OVR;
920 	if (iflag & INPCK)
921 		up->port.read_status_mask |= CRC_ERR | PAR_ERR;
922 	if (iflag & (IGNBRK | BRKINT | PARMRK))
923 		up->port.read_status_mask |= BRK_ABRT;
924 
925 	up->port.ignore_status_mask = 0;
926 	if (iflag & IGNPAR)
927 		up->port.ignore_status_mask |= CRC_ERR | PAR_ERR;
928 	if (iflag & IGNBRK) {
929 		up->port.ignore_status_mask |= BRK_ABRT;
930 		if (iflag & IGNPAR)
931 			up->port.ignore_status_mask |= Rx_OVR;
932 	}
933 
934 	if ((cflag & CREAD) == 0)
935 		up->port.ignore_status_mask = 0xff;
936 }
937 
938 /* The port lock is not held.  */
939 static void
940 sunzilog_set_termios(struct uart_port *port, struct ktermios *termios,
941 		     struct ktermios *old)
942 {
943 	struct uart_sunzilog_port *up =
944 		container_of(port, struct uart_sunzilog_port, port);
945 	unsigned long flags;
946 	int baud, brg;
947 
948 	baud = uart_get_baud_rate(port, termios, old, 1200, 76800);
949 
950 	spin_lock_irqsave(&up->port.lock, flags);
951 
952 	brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
953 
954 	sunzilog_convert_to_zs(up, termios->c_cflag, termios->c_iflag, brg);
955 
956 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
957 		up->flags |= SUNZILOG_FLAG_MODEM_STATUS;
958 	else
959 		up->flags &= ~SUNZILOG_FLAG_MODEM_STATUS;
960 
961 	up->cflag = termios->c_cflag;
962 
963 	sunzilog_maybe_update_regs(up, ZILOG_CHANNEL_FROM_PORT(port));
964 
965 	uart_update_timeout(port, termios->c_cflag, baud);
966 
967 	spin_unlock_irqrestore(&up->port.lock, flags);
968 }
969 
970 static const char *sunzilog_type(struct uart_port *port)
971 {
972 	struct uart_sunzilog_port *up = UART_ZILOG(port);
973 
974 	return (up->flags & SUNZILOG_FLAG_ESCC) ? "zs (ESCC)" : "zs";
975 }
976 
977 /* We do not request/release mappings of the registers here, this
978  * happens at early serial probe time.
979  */
980 static void sunzilog_release_port(struct uart_port *port)
981 {
982 }
983 
984 static int sunzilog_request_port(struct uart_port *port)
985 {
986 	return 0;
987 }
988 
989 /* These do not need to do anything interesting either.  */
990 static void sunzilog_config_port(struct uart_port *port, int flags)
991 {
992 }
993 
994 /* We do not support letting the user mess with the divisor, IRQ, etc. */
995 static int sunzilog_verify_port(struct uart_port *port, struct serial_struct *ser)
996 {
997 	return -EINVAL;
998 }
999 
1000 #ifdef CONFIG_CONSOLE_POLL
1001 static int sunzilog_get_poll_char(struct uart_port *port)
1002 {
1003 	unsigned char ch, r1;
1004 	struct uart_sunzilog_port *up =
1005 		container_of(port, struct uart_sunzilog_port, port);
1006 	struct zilog_channel __iomem *channel
1007 		= ZILOG_CHANNEL_FROM_PORT(&up->port);
1008 
1009 
1010 	r1 = read_zsreg(channel, R1);
1011 	if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
1012 		writeb(ERR_RES, &channel->control);
1013 		ZSDELAY();
1014 		ZS_WSYNC(channel);
1015 	}
1016 
1017 	ch = readb(&channel->control);
1018 	ZSDELAY();
1019 
1020 	/* This funny hack depends upon BRK_ABRT not interfering
1021 	 * with the other bits we care about in R1.
1022 	 */
1023 	if (ch & BRK_ABRT)
1024 		r1 |= BRK_ABRT;
1025 
1026 	if (!(ch & Rx_CH_AV))
1027 		return NO_POLL_CHAR;
1028 
1029 	ch = readb(&channel->data);
1030 	ZSDELAY();
1031 
1032 	ch &= up->parity_mask;
1033 	return ch;
1034 }
1035 
1036 static void sunzilog_put_poll_char(struct uart_port *port,
1037 			unsigned char ch)
1038 {
1039 	struct uart_sunzilog_port *up =
1040 		container_of(port, struct uart_sunzilog_port, port);
1041 
1042 	sunzilog_putchar(&up->port, ch);
1043 }
1044 #endif /* CONFIG_CONSOLE_POLL */
1045 
1046 static const struct uart_ops sunzilog_pops = {
1047 	.tx_empty	=	sunzilog_tx_empty,
1048 	.set_mctrl	=	sunzilog_set_mctrl,
1049 	.get_mctrl	=	sunzilog_get_mctrl,
1050 	.stop_tx	=	sunzilog_stop_tx,
1051 	.start_tx	=	sunzilog_start_tx,
1052 	.stop_rx	=	sunzilog_stop_rx,
1053 	.enable_ms	=	sunzilog_enable_ms,
1054 	.break_ctl	=	sunzilog_break_ctl,
1055 	.startup	=	sunzilog_startup,
1056 	.shutdown	=	sunzilog_shutdown,
1057 	.set_termios	=	sunzilog_set_termios,
1058 	.type		=	sunzilog_type,
1059 	.release_port	=	sunzilog_release_port,
1060 	.request_port	=	sunzilog_request_port,
1061 	.config_port	=	sunzilog_config_port,
1062 	.verify_port	=	sunzilog_verify_port,
1063 #ifdef CONFIG_CONSOLE_POLL
1064 	.poll_get_char	=	sunzilog_get_poll_char,
1065 	.poll_put_char	=	sunzilog_put_poll_char,
1066 #endif
1067 };
1068 
1069 static int uart_chip_count;
1070 static struct uart_sunzilog_port *sunzilog_port_table;
1071 static struct zilog_layout __iomem **sunzilog_chip_regs;
1072 
1073 static struct uart_sunzilog_port *sunzilog_irq_chain;
1074 
1075 static struct uart_driver sunzilog_reg = {
1076 	.owner		=	THIS_MODULE,
1077 	.driver_name	=	"sunzilog",
1078 	.dev_name	=	"ttyS",
1079 	.major		=	TTY_MAJOR,
1080 };
1081 
1082 static int __init sunzilog_alloc_tables(int num_sunzilog)
1083 {
1084 	struct uart_sunzilog_port *up;
1085 	unsigned long size;
1086 	int num_channels = num_sunzilog * 2;
1087 	int i;
1088 
1089 	size = num_channels * sizeof(struct uart_sunzilog_port);
1090 	sunzilog_port_table = kzalloc(size, GFP_KERNEL);
1091 	if (!sunzilog_port_table)
1092 		return -ENOMEM;
1093 
1094 	for (i = 0; i < num_channels; i++) {
1095 		up = &sunzilog_port_table[i];
1096 
1097 		spin_lock_init(&up->port.lock);
1098 
1099 		if (i == 0)
1100 			sunzilog_irq_chain = up;
1101 
1102 		if (i < num_channels - 1)
1103 			up->next = up + 1;
1104 		else
1105 			up->next = NULL;
1106 	}
1107 
1108 	size = num_sunzilog * sizeof(struct zilog_layout __iomem *);
1109 	sunzilog_chip_regs = kzalloc(size, GFP_KERNEL);
1110 	if (!sunzilog_chip_regs) {
1111 		kfree(sunzilog_port_table);
1112 		sunzilog_irq_chain = NULL;
1113 		return -ENOMEM;
1114 	}
1115 
1116 	return 0;
1117 }
1118 
1119 static void sunzilog_free_tables(void)
1120 {
1121 	kfree(sunzilog_port_table);
1122 	sunzilog_irq_chain = NULL;
1123 	kfree(sunzilog_chip_regs);
1124 }
1125 
1126 #define ZS_PUT_CHAR_MAX_DELAY	2000	/* 10 ms */
1127 
1128 static void __maybe_unused sunzilog_putchar(struct uart_port *port, int ch)
1129 {
1130 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
1131 	int loops = ZS_PUT_CHAR_MAX_DELAY;
1132 
1133 	/* This is a timed polling loop so do not switch the explicit
1134 	 * udelay with ZSDELAY as that is a NOP on some platforms.  -DaveM
1135 	 */
1136 	do {
1137 		unsigned char val = readb(&channel->control);
1138 		if (val & Tx_BUF_EMP) {
1139 			ZSDELAY();
1140 			break;
1141 		}
1142 		udelay(5);
1143 	} while (--loops);
1144 
1145 	writeb(ch, &channel->data);
1146 	ZSDELAY();
1147 	ZS_WSYNC(channel);
1148 }
1149 
1150 #ifdef CONFIG_SERIO
1151 
1152 static DEFINE_SPINLOCK(sunzilog_serio_lock);
1153 
1154 static int sunzilog_serio_write(struct serio *serio, unsigned char ch)
1155 {
1156 	struct uart_sunzilog_port *up = serio->port_data;
1157 	unsigned long flags;
1158 
1159 	spin_lock_irqsave(&sunzilog_serio_lock, flags);
1160 
1161 	sunzilog_putchar(&up->port, ch);
1162 
1163 	spin_unlock_irqrestore(&sunzilog_serio_lock, flags);
1164 
1165 	return 0;
1166 }
1167 
1168 static int sunzilog_serio_open(struct serio *serio)
1169 {
1170 	struct uart_sunzilog_port *up = serio->port_data;
1171 	unsigned long flags;
1172 	int ret;
1173 
1174 	spin_lock_irqsave(&sunzilog_serio_lock, flags);
1175 	if (!up->serio_open) {
1176 		up->serio_open = 1;
1177 		ret = 0;
1178 	} else
1179 		ret = -EBUSY;
1180 	spin_unlock_irqrestore(&sunzilog_serio_lock, flags);
1181 
1182 	return ret;
1183 }
1184 
1185 static void sunzilog_serio_close(struct serio *serio)
1186 {
1187 	struct uart_sunzilog_port *up = serio->port_data;
1188 	unsigned long flags;
1189 
1190 	spin_lock_irqsave(&sunzilog_serio_lock, flags);
1191 	up->serio_open = 0;
1192 	spin_unlock_irqrestore(&sunzilog_serio_lock, flags);
1193 }
1194 
1195 #endif /* CONFIG_SERIO */
1196 
1197 #ifdef CONFIG_SERIAL_SUNZILOG_CONSOLE
1198 static void
1199 sunzilog_console_write(struct console *con, const char *s, unsigned int count)
1200 {
1201 	struct uart_sunzilog_port *up = &sunzilog_port_table[con->index];
1202 	unsigned long flags;
1203 	int locked = 1;
1204 
1205 	if (up->port.sysrq || oops_in_progress)
1206 		locked = spin_trylock_irqsave(&up->port.lock, flags);
1207 	else
1208 		spin_lock_irqsave(&up->port.lock, flags);
1209 
1210 	uart_console_write(&up->port, s, count, sunzilog_putchar);
1211 	udelay(2);
1212 
1213 	if (locked)
1214 		spin_unlock_irqrestore(&up->port.lock, flags);
1215 }
1216 
1217 static int __init sunzilog_console_setup(struct console *con, char *options)
1218 {
1219 	struct uart_sunzilog_port *up = &sunzilog_port_table[con->index];
1220 	unsigned long flags;
1221 	int baud, brg;
1222 
1223 	if (up->port.type != PORT_SUNZILOG)
1224 		return -EINVAL;
1225 
1226 	printk(KERN_INFO "Console: ttyS%d (SunZilog zs%d)\n",
1227 	       (sunzilog_reg.minor - 64) + con->index, con->index);
1228 
1229 	/* Get firmware console settings.  */
1230 	sunserial_console_termios(con, up->port.dev->of_node);
1231 
1232 	/* Firmware console speed is limited to 150-->38400 baud so
1233 	 * this hackish cflag thing is OK.
1234 	 */
1235 	switch (con->cflag & CBAUD) {
1236 	case B150: baud = 150; break;
1237 	case B300: baud = 300; break;
1238 	case B600: baud = 600; break;
1239 	case B1200: baud = 1200; break;
1240 	case B2400: baud = 2400; break;
1241 	case B4800: baud = 4800; break;
1242 	default: case B9600: baud = 9600; break;
1243 	case B19200: baud = 19200; break;
1244 	case B38400: baud = 38400; break;
1245 	}
1246 
1247 	brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
1248 
1249 	spin_lock_irqsave(&up->port.lock, flags);
1250 
1251 	up->curregs[R15] |= BRKIE;
1252 	sunzilog_convert_to_zs(up, con->cflag, 0, brg);
1253 
1254 	sunzilog_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
1255 	__sunzilog_startup(up);
1256 
1257 	spin_unlock_irqrestore(&up->port.lock, flags);
1258 
1259 	return 0;
1260 }
1261 
1262 static struct console sunzilog_console_ops = {
1263 	.name	=	"ttyS",
1264 	.write	=	sunzilog_console_write,
1265 	.device	=	uart_console_device,
1266 	.setup	=	sunzilog_console_setup,
1267 	.flags	=	CON_PRINTBUFFER,
1268 	.index	=	-1,
1269 	.data   =	&sunzilog_reg,
1270 };
1271 
1272 static inline struct console *SUNZILOG_CONSOLE(void)
1273 {
1274 	return &sunzilog_console_ops;
1275 }
1276 
1277 #else
1278 #define SUNZILOG_CONSOLE()	(NULL)
1279 #endif
1280 
1281 static void sunzilog_init_kbdms(struct uart_sunzilog_port *up)
1282 {
1283 	int baud, brg;
1284 
1285 	if (up->flags & SUNZILOG_FLAG_CONS_KEYB) {
1286 		up->cflag = B1200 | CS8 | CLOCAL | CREAD;
1287 		baud = 1200;
1288 	} else {
1289 		up->cflag = B4800 | CS8 | CLOCAL | CREAD;
1290 		baud = 4800;
1291 	}
1292 
1293 	up->curregs[R15] |= BRKIE;
1294 	brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
1295 	sunzilog_convert_to_zs(up, up->cflag, 0, brg);
1296 	sunzilog_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
1297 	__sunzilog_startup(up);
1298 }
1299 
1300 #ifdef CONFIG_SERIO
1301 static void sunzilog_register_serio(struct uart_sunzilog_port *up)
1302 {
1303 	struct serio *serio = &up->serio;
1304 
1305 	serio->port_data = up;
1306 
1307 	serio->id.type = SERIO_RS232;
1308 	if (up->flags & SUNZILOG_FLAG_CONS_KEYB) {
1309 		serio->id.proto = SERIO_SUNKBD;
1310 		strlcpy(serio->name, "zskbd", sizeof(serio->name));
1311 	} else {
1312 		serio->id.proto = SERIO_SUN;
1313 		serio->id.extra = 1;
1314 		strlcpy(serio->name, "zsms", sizeof(serio->name));
1315 	}
1316 	strlcpy(serio->phys,
1317 		((up->flags & SUNZILOG_FLAG_CONS_KEYB) ?
1318 		 "zs/serio0" : "zs/serio1"),
1319 		sizeof(serio->phys));
1320 
1321 	serio->write = sunzilog_serio_write;
1322 	serio->open = sunzilog_serio_open;
1323 	serio->close = sunzilog_serio_close;
1324 	serio->dev.parent = up->port.dev;
1325 
1326 	serio_register_port(serio);
1327 }
1328 #endif
1329 
1330 static void sunzilog_init_hw(struct uart_sunzilog_port *up)
1331 {
1332 	struct zilog_channel __iomem *channel;
1333 	unsigned long flags;
1334 	int baud, brg;
1335 
1336 	channel = ZILOG_CHANNEL_FROM_PORT(&up->port);
1337 
1338 	spin_lock_irqsave(&up->port.lock, flags);
1339 	if (ZS_IS_CHANNEL_A(up)) {
1340 		write_zsreg(channel, R9, FHWRES);
1341 		ZSDELAY_LONG();
1342 		(void) read_zsreg(channel, R0);
1343 	}
1344 
1345 	if (up->flags & (SUNZILOG_FLAG_CONS_KEYB |
1346 			 SUNZILOG_FLAG_CONS_MOUSE)) {
1347 		up->curregs[R1] = EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB;
1348 		up->curregs[R4] = PAR_EVEN | X16CLK | SB1;
1349 		up->curregs[R3] = RxENAB | Rx8;
1350 		up->curregs[R5] = TxENAB | Tx8;
1351 		up->curregs[R6] = 0x00; /* SDLC Address */
1352 		up->curregs[R7] = 0x7E; /* SDLC Flag    */
1353 		up->curregs[R9] = NV;
1354 		up->curregs[R7p] = 0x00;
1355 		sunzilog_init_kbdms(up);
1356 		/* Only enable interrupts if an ISR handler available */
1357 		if (up->flags & SUNZILOG_FLAG_ISR_HANDLER)
1358 			up->curregs[R9] |= MIE;
1359 		write_zsreg(channel, R9, up->curregs[R9]);
1360 	} else {
1361 		/* Normal serial TTY. */
1362 		up->parity_mask = 0xff;
1363 		up->curregs[R1] = EXT_INT_ENAB | INT_ALL_Rx | TxINT_ENAB;
1364 		up->curregs[R4] = PAR_EVEN | X16CLK | SB1;
1365 		up->curregs[R3] = RxENAB | Rx8;
1366 		up->curregs[R5] = TxENAB | Tx8;
1367 		up->curregs[R6] = 0x00; /* SDLC Address */
1368 		up->curregs[R7] = 0x7E; /* SDLC Flag    */
1369 		up->curregs[R9] = NV;
1370 		up->curregs[R10] = NRZ;
1371 		up->curregs[R11] = TCBR | RCBR;
1372 		baud = 9600;
1373 		brg = BPS_TO_BRG(baud, ZS_CLOCK / ZS_CLOCK_DIVISOR);
1374 		up->curregs[R12] = (brg & 0xff);
1375 		up->curregs[R13] = (brg >> 8) & 0xff;
1376 		up->curregs[R14] = BRSRC | BRENAB;
1377 		up->curregs[R15] = FIFOEN; /* Use FIFO if on ESCC */
1378 		up->curregs[R7p] = TxFIFO_LVL | RxFIFO_LVL;
1379 		if (__load_zsregs(channel, up->curregs)) {
1380 			up->flags |= SUNZILOG_FLAG_ESCC;
1381 		}
1382 		/* Only enable interrupts if an ISR handler available */
1383 		if (up->flags & SUNZILOG_FLAG_ISR_HANDLER)
1384 			up->curregs[R9] |= MIE;
1385 		write_zsreg(channel, R9, up->curregs[R9]);
1386 	}
1387 
1388 	spin_unlock_irqrestore(&up->port.lock, flags);
1389 
1390 #ifdef CONFIG_SERIO
1391 	if (up->flags & (SUNZILOG_FLAG_CONS_KEYB |
1392 			 SUNZILOG_FLAG_CONS_MOUSE))
1393 		sunzilog_register_serio(up);
1394 #endif
1395 }
1396 
1397 static int zilog_irq;
1398 
1399 static int zs_probe(struct platform_device *op)
1400 {
1401 	static int kbm_inst, uart_inst;
1402 	int inst;
1403 	struct uart_sunzilog_port *up;
1404 	struct zilog_layout __iomem *rp;
1405 	int keyboard_mouse = 0;
1406 	int err;
1407 
1408 	if (of_find_property(op->dev.of_node, "keyboard", NULL))
1409 		keyboard_mouse = 1;
1410 
1411 	/* uarts must come before keyboards/mice */
1412 	if (keyboard_mouse)
1413 		inst = uart_chip_count + kbm_inst;
1414 	else
1415 		inst = uart_inst;
1416 
1417 	sunzilog_chip_regs[inst] = of_ioremap(&op->resource[0], 0,
1418 					      sizeof(struct zilog_layout),
1419 					      "zs");
1420 	if (!sunzilog_chip_regs[inst])
1421 		return -ENOMEM;
1422 
1423 	rp = sunzilog_chip_regs[inst];
1424 
1425 	if (!zilog_irq)
1426 		zilog_irq = op->archdata.irqs[0];
1427 
1428 	up = &sunzilog_port_table[inst * 2];
1429 
1430 	/* Channel A */
1431 	up[0].port.mapbase = op->resource[0].start + 0x00;
1432 	up[0].port.membase = (void __iomem *) &rp->channelA;
1433 	up[0].port.iotype = UPIO_MEM;
1434 	up[0].port.irq = op->archdata.irqs[0];
1435 	up[0].port.uartclk = ZS_CLOCK;
1436 	up[0].port.fifosize = 1;
1437 	up[0].port.ops = &sunzilog_pops;
1438 	up[0].port.type = PORT_SUNZILOG;
1439 	up[0].port.flags = 0;
1440 	up[0].port.line = (inst * 2) + 0;
1441 	up[0].port.dev = &op->dev;
1442 	up[0].flags |= SUNZILOG_FLAG_IS_CHANNEL_A;
1443 	up[0].port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SUNZILOG_CONSOLE);
1444 	if (keyboard_mouse)
1445 		up[0].flags |= SUNZILOG_FLAG_CONS_KEYB;
1446 	sunzilog_init_hw(&up[0]);
1447 
1448 	/* Channel B */
1449 	up[1].port.mapbase = op->resource[0].start + 0x04;
1450 	up[1].port.membase = (void __iomem *) &rp->channelB;
1451 	up[1].port.iotype = UPIO_MEM;
1452 	up[1].port.irq = op->archdata.irqs[0];
1453 	up[1].port.uartclk = ZS_CLOCK;
1454 	up[1].port.fifosize = 1;
1455 	up[1].port.ops = &sunzilog_pops;
1456 	up[1].port.type = PORT_SUNZILOG;
1457 	up[1].port.flags = 0;
1458 	up[1].port.line = (inst * 2) + 1;
1459 	up[1].port.dev = &op->dev;
1460 	up[1].flags |= 0;
1461 	up[1].port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SUNZILOG_CONSOLE);
1462 	if (keyboard_mouse)
1463 		up[1].flags |= SUNZILOG_FLAG_CONS_MOUSE;
1464 	sunzilog_init_hw(&up[1]);
1465 
1466 	if (!keyboard_mouse) {
1467 		if (sunserial_console_match(SUNZILOG_CONSOLE(), op->dev.of_node,
1468 					    &sunzilog_reg, up[0].port.line,
1469 					    false))
1470 			up->flags |= SUNZILOG_FLAG_IS_CONS;
1471 		err = uart_add_one_port(&sunzilog_reg, &up[0].port);
1472 		if (err) {
1473 			of_iounmap(&op->resource[0],
1474 				   rp, sizeof(struct zilog_layout));
1475 			return err;
1476 		}
1477 		if (sunserial_console_match(SUNZILOG_CONSOLE(), op->dev.of_node,
1478 					    &sunzilog_reg, up[1].port.line,
1479 					    false))
1480 			up->flags |= SUNZILOG_FLAG_IS_CONS;
1481 		err = uart_add_one_port(&sunzilog_reg, &up[1].port);
1482 		if (err) {
1483 			uart_remove_one_port(&sunzilog_reg, &up[0].port);
1484 			of_iounmap(&op->resource[0],
1485 				   rp, sizeof(struct zilog_layout));
1486 			return err;
1487 		}
1488 		uart_inst++;
1489 	} else {
1490 		printk(KERN_INFO "%s: Keyboard at MMIO 0x%llx (irq = %d) "
1491 		       "is a %s\n",
1492 		       dev_name(&op->dev),
1493 		       (unsigned long long) up[0].port.mapbase,
1494 		       op->archdata.irqs[0], sunzilog_type(&up[0].port));
1495 		printk(KERN_INFO "%s: Mouse at MMIO 0x%llx (irq = %d) "
1496 		       "is a %s\n",
1497 		       dev_name(&op->dev),
1498 		       (unsigned long long) up[1].port.mapbase,
1499 		       op->archdata.irqs[0], sunzilog_type(&up[1].port));
1500 		kbm_inst++;
1501 	}
1502 
1503 	platform_set_drvdata(op, &up[0]);
1504 
1505 	return 0;
1506 }
1507 
1508 static void zs_remove_one(struct uart_sunzilog_port *up)
1509 {
1510 	if (ZS_IS_KEYB(up) || ZS_IS_MOUSE(up)) {
1511 #ifdef CONFIG_SERIO
1512 		serio_unregister_port(&up->serio);
1513 #endif
1514 	} else
1515 		uart_remove_one_port(&sunzilog_reg, &up->port);
1516 }
1517 
1518 static int zs_remove(struct platform_device *op)
1519 {
1520 	struct uart_sunzilog_port *up = platform_get_drvdata(op);
1521 	struct zilog_layout __iomem *regs;
1522 
1523 	zs_remove_one(&up[0]);
1524 	zs_remove_one(&up[1]);
1525 
1526 	regs = sunzilog_chip_regs[up[0].port.line / 2];
1527 	of_iounmap(&op->resource[0], regs, sizeof(struct zilog_layout));
1528 
1529 	return 0;
1530 }
1531 
1532 static const struct of_device_id zs_match[] = {
1533 	{
1534 		.name = "zs",
1535 	},
1536 	{},
1537 };
1538 MODULE_DEVICE_TABLE(of, zs_match);
1539 
1540 static struct platform_driver zs_driver = {
1541 	.driver = {
1542 		.name = "zs",
1543 		.of_match_table = zs_match,
1544 	},
1545 	.probe		= zs_probe,
1546 	.remove		= zs_remove,
1547 };
1548 
1549 static int __init sunzilog_init(void)
1550 {
1551 	struct device_node *dp;
1552 	int err;
1553 	int num_keybms = 0;
1554 	int num_sunzilog = 0;
1555 
1556 	for_each_node_by_name(dp, "zs") {
1557 		num_sunzilog++;
1558 		if (of_find_property(dp, "keyboard", NULL))
1559 			num_keybms++;
1560 	}
1561 
1562 	if (num_sunzilog) {
1563 		err = sunzilog_alloc_tables(num_sunzilog);
1564 		if (err)
1565 			goto out;
1566 
1567 		uart_chip_count = num_sunzilog - num_keybms;
1568 
1569 		err = sunserial_register_minors(&sunzilog_reg,
1570 						uart_chip_count * 2);
1571 		if (err)
1572 			goto out_free_tables;
1573 	}
1574 
1575 	err = platform_driver_register(&zs_driver);
1576 	if (err)
1577 		goto out_unregister_uart;
1578 
1579 	if (zilog_irq) {
1580 		struct uart_sunzilog_port *up = sunzilog_irq_chain;
1581 		err = request_irq(zilog_irq, sunzilog_interrupt, IRQF_SHARED,
1582 				  "zs", sunzilog_irq_chain);
1583 		if (err)
1584 			goto out_unregister_driver;
1585 
1586 		/* Enable Interrupts */
1587 		while (up) {
1588 			struct zilog_channel __iomem *channel;
1589 
1590 			/* printk (KERN_INFO "Enable IRQ for ZILOG Hardware %p\n", up); */
1591 			channel          = ZILOG_CHANNEL_FROM_PORT(&up->port);
1592 			up->flags       |= SUNZILOG_FLAG_ISR_HANDLER;
1593 			up->curregs[R9] |= MIE;
1594 			write_zsreg(channel, R9, up->curregs[R9]);
1595 			up = up->next;
1596 		}
1597 	}
1598 
1599 out:
1600 	return err;
1601 
1602 out_unregister_driver:
1603 	platform_driver_unregister(&zs_driver);
1604 
1605 out_unregister_uart:
1606 	if (num_sunzilog) {
1607 		sunserial_unregister_minors(&sunzilog_reg, num_sunzilog);
1608 		sunzilog_reg.cons = NULL;
1609 	}
1610 
1611 out_free_tables:
1612 	sunzilog_free_tables();
1613 	goto out;
1614 }
1615 
1616 static void __exit sunzilog_exit(void)
1617 {
1618 	platform_driver_unregister(&zs_driver);
1619 
1620 	if (zilog_irq) {
1621 		struct uart_sunzilog_port *up = sunzilog_irq_chain;
1622 
1623 		/* Disable Interrupts */
1624 		while (up) {
1625 			struct zilog_channel __iomem *channel;
1626 
1627 			/* printk (KERN_INFO "Disable IRQ for ZILOG Hardware %p\n", up); */
1628 			channel          = ZILOG_CHANNEL_FROM_PORT(&up->port);
1629 			up->flags       &= ~SUNZILOG_FLAG_ISR_HANDLER;
1630 			up->curregs[R9] &= ~MIE;
1631 			write_zsreg(channel, R9, up->curregs[R9]);
1632 			up = up->next;
1633 		}
1634 
1635 		free_irq(zilog_irq, sunzilog_irq_chain);
1636 		zilog_irq = 0;
1637 	}
1638 
1639 	if (sunzilog_reg.nr) {
1640 		sunserial_unregister_minors(&sunzilog_reg, sunzilog_reg.nr);
1641 		sunzilog_free_tables();
1642 	}
1643 }
1644 
1645 module_init(sunzilog_init);
1646 module_exit(sunzilog_exit);
1647 
1648 MODULE_AUTHOR("David S. Miller");
1649 MODULE_DESCRIPTION("Sun Zilog serial port driver");
1650 MODULE_VERSION("2.0");
1651 MODULE_LICENSE("GPL");
1652