xref: /linux/drivers/s390/char/con3215.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  *  drivers/s390/char/con3215.c
3  *    3215 line mode terminal driver.
4  *
5  *  S390 version
6  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
7  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
8  *
9  *  Updated:
10  *   Aug-2000: Added tab support
11  *	       Dan Morrison, IBM Corporation (dmorriso@cse.buffalo.edu)
12  */
13 
14 #include <linux/config.h>
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/kdev_t.h>
18 #include <linux/tty.h>
19 #include <linux/tty_flip.h>
20 #include <linux/vt_kern.h>
21 #include <linux/init.h>
22 #include <linux/console.h>
23 #include <linux/interrupt.h>
24 #include <linux/err.h>
25 
26 #include <linux/slab.h>
27 #include <linux/bootmem.h>
28 
29 #include <asm/ccwdev.h>
30 #include <asm/cio.h>
31 #include <asm/io.h>
32 #include <asm/ebcdic.h>
33 #include <asm/uaccess.h>
34 #include <asm/delay.h>
35 #include <asm/cpcmd.h>
36 #include <asm/setup.h>
37 
38 #include "ctrlchar.h"
39 
40 #define NR_3215		    1
41 #define NR_3215_REQ	    (4*NR_3215)
42 #define RAW3215_BUFFER_SIZE 65536     /* output buffer size */
43 #define RAW3215_INBUF_SIZE  256	      /* input buffer size */
44 #define RAW3215_MIN_SPACE   128	      /* minimum free space for wakeup */
45 #define RAW3215_MIN_WRITE   1024      /* min. length for immediate output */
46 #define RAW3215_MAX_BYTES   3968      /* max. bytes to write with one ssch */
47 #define RAW3215_MAX_NEWLINE 50	      /* max. lines to write with one ssch */
48 #define RAW3215_NR_CCWS	    3
49 #define RAW3215_TIMEOUT	    HZ/10     /* time for delayed output */
50 
51 #define RAW3215_FIXED	    1	      /* 3215 console device is not be freed */
52 #define RAW3215_ACTIVE	    2	      /* set if the device is in use */
53 #define RAW3215_WORKING	    4	      /* set if a request is being worked on */
54 #define RAW3215_THROTTLED   8	      /* set if reading is disabled */
55 #define RAW3215_STOPPED	    16	      /* set if writing is disabled */
56 #define RAW3215_CLOSING	    32	      /* set while in close process */
57 #define RAW3215_TIMER_RUNS  64	      /* set if the output delay timer is on */
58 #define RAW3215_FLUSHING    128	      /* set to flush buffer (no delay) */
59 
60 #define TAB_STOP_SIZE	    8	      /* tab stop size */
61 
62 /*
63  * Request types for a 3215 device
64  */
65 enum raw3215_type {
66 	RAW3215_FREE, RAW3215_READ, RAW3215_WRITE
67 };
68 
69 /*
70  * Request structure for a 3215 device
71  */
72 struct raw3215_req {
73 	enum raw3215_type type;	      /* type of the request */
74 	int start, len;		      /* start index & len in output buffer */
75 	int delayable;		      /* indication to wait for more data */
76 	int residual;		      /* residual count for read request */
77 	struct ccw1 ccws[RAW3215_NR_CCWS]; /* space for the channel program */
78 	struct raw3215_info *info;    /* pointer to main structure */
79 	struct raw3215_req *next;     /* pointer to next request */
80 } __attribute__ ((aligned(8)));
81 
82 struct raw3215_info {
83 	struct ccw_device *cdev;      /* device for tty driver */
84 	spinlock_t *lock;	      /* pointer to irq lock */
85 	int flags;		      /* state flags */
86 	char *buffer;		      /* pointer to output buffer */
87 	char *inbuf;		      /* pointer to input buffer */
88 	int head;		      /* first free byte in output buffer */
89 	int count;		      /* number of bytes in output buffer */
90 	int written;		      /* number of bytes in write requests */
91 	struct tty_struct *tty;	      /* pointer to tty structure if present */
92 	struct tasklet_struct tasklet;
93 	struct raw3215_req *queued_read; /* pointer to queued read requests */
94 	struct raw3215_req *queued_write;/* pointer to queued write requests */
95 	wait_queue_head_t empty_wait; /* wait queue for flushing */
96 	struct timer_list timer;      /* timer for delayed output */
97 	char *message;		      /* pending message from raw3215_irq */
98 	int msg_dstat;		      /* dstat for pending message */
99 	int msg_cstat;		      /* cstat for pending message */
100 	int line_pos;		      /* position on the line (for tabs) */
101 	char ubuffer[80];	      /* copy_from_user buffer */
102 };
103 
104 /* array of 3215 devices structures */
105 static struct raw3215_info *raw3215[NR_3215];
106 /* spinlock to protect the raw3215 array */
107 static DEFINE_SPINLOCK(raw3215_device_lock);
108 /* list of free request structures */
109 static struct raw3215_req *raw3215_freelist;
110 /* spinlock to protect free list */
111 static spinlock_t raw3215_freelist_lock;
112 
113 static struct tty_driver *tty3215_driver;
114 
115 /*
116  * Get a request structure from the free list
117  */
118 static inline struct raw3215_req *
119 raw3215_alloc_req(void) {
120 	struct raw3215_req *req;
121 	unsigned long flags;
122 
123 	spin_lock_irqsave(&raw3215_freelist_lock, flags);
124 	req = raw3215_freelist;
125 	raw3215_freelist = req->next;
126 	spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
127 	return req;
128 }
129 
130 /*
131  * Put a request structure back to the free list
132  */
133 static inline void
134 raw3215_free_req(struct raw3215_req *req) {
135 	unsigned long flags;
136 
137 	if (req->type == RAW3215_FREE)
138 		return;		/* don't free a free request */
139 	req->type = RAW3215_FREE;
140 	spin_lock_irqsave(&raw3215_freelist_lock, flags);
141 	req->next = raw3215_freelist;
142 	raw3215_freelist = req;
143 	spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
144 }
145 
146 /*
147  * Set up a read request that reads up to 160 byte from the 3215 device.
148  * If there is a queued read request it is used, but that shouldn't happen
149  * because a 3215 terminal won't accept a new read before the old one is
150  * completed.
151  */
152 static void
153 raw3215_mk_read_req(struct raw3215_info *raw)
154 {
155 	struct raw3215_req *req;
156 	struct ccw1 *ccw;
157 
158 	/* there can only be ONE read request at a time */
159 	req = raw->queued_read;
160 	if (req == NULL) {
161 		/* no queued read request, use new req structure */
162 		req = raw3215_alloc_req();
163 		req->type = RAW3215_READ;
164 		req->info = raw;
165 		raw->queued_read = req;
166 	}
167 
168 	ccw = req->ccws;
169 	ccw->cmd_code = 0x0A; /* read inquiry */
170 	ccw->flags = 0x20;    /* ignore incorrect length */
171 	ccw->count = 160;
172 	ccw->cda = (__u32) __pa(raw->inbuf);
173 }
174 
175 /*
176  * Set up a write request with the information from the main structure.
177  * A ccw chain is created that writes as much as possible from the output
178  * buffer to the 3215 device. If a queued write exists it is replaced by
179  * the new, probably lengthened request.
180  */
181 static void
182 raw3215_mk_write_req(struct raw3215_info *raw)
183 {
184 	struct raw3215_req *req;
185 	struct ccw1 *ccw;
186 	int len, count, ix, lines;
187 
188 	if (raw->count <= raw->written)
189 		return;
190 	/* check if there is a queued write request */
191 	req = raw->queued_write;
192 	if (req == NULL) {
193 		/* no queued write request, use new req structure */
194 		req = raw3215_alloc_req();
195 		req->type = RAW3215_WRITE;
196 		req->info = raw;
197 		raw->queued_write = req;
198 	} else {
199 		raw->written -= req->len;
200 	}
201 
202 	ccw = req->ccws;
203 	req->start = (raw->head - raw->count + raw->written) &
204 		     (RAW3215_BUFFER_SIZE - 1);
205 	/*
206 	 * now we have to count newlines. We can at max accept
207 	 * RAW3215_MAX_NEWLINE newlines in a single ssch due to
208 	 * a restriction in VM
209 	 */
210 	lines = 0;
211 	ix = req->start;
212 	while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) {
213 		if (raw->buffer[ix] == 0x15)
214 			lines++;
215 		ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
216 	}
217 	len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1;
218 	if (len > RAW3215_MAX_BYTES)
219 		len = RAW3215_MAX_BYTES;
220 	req->len = len;
221 	raw->written += len;
222 
223 	/* set the indication if we should try to enlarge this request */
224 	req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE);
225 
226 	ix = req->start;
227 	while (len > 0) {
228 		if (ccw > req->ccws)
229 			ccw[-1].flags |= 0x40; /* use command chaining */
230 		ccw->cmd_code = 0x01; /* write, auto carrier return */
231 		ccw->flags = 0x20;    /* ignore incorrect length ind.  */
232 		ccw->cda =
233 			(__u32) __pa(raw->buffer + ix);
234 		count = len;
235 		if (ix + count > RAW3215_BUFFER_SIZE)
236 			count = RAW3215_BUFFER_SIZE - ix;
237 		ccw->count = count;
238 		len -= count;
239 		ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1);
240 		ccw++;
241 	}
242 	/*
243 	 * Add a NOP to the channel program. 3215 devices are purely
244 	 * emulated and its much better to avoid the channel end
245 	 * interrupt in this case.
246 	 */
247 	if (ccw > req->ccws)
248 		ccw[-1].flags |= 0x40; /* use command chaining */
249 	ccw->cmd_code = 0x03; /* NOP */
250 	ccw->flags = 0;
251 	ccw->cda = 0;
252 	ccw->count = 1;
253 }
254 
255 /*
256  * Start a read or a write request
257  */
258 static void
259 raw3215_start_io(struct raw3215_info *raw)
260 {
261 	struct raw3215_req *req;
262 	int res;
263 
264 	req = raw->queued_read;
265 	if (req != NULL &&
266 	    !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) {
267 		/* dequeue request */
268 		raw->queued_read = NULL;
269 		res = ccw_device_start(raw->cdev, req->ccws,
270 				       (unsigned long) req, 0, 0);
271 		if (res != 0) {
272 			/* do_IO failed, put request back to queue */
273 			raw->queued_read = req;
274 		} else {
275 			raw->flags |= RAW3215_WORKING;
276 		}
277 	}
278 	req = raw->queued_write;
279 	if (req != NULL &&
280 	    !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) {
281 		/* dequeue request */
282 		raw->queued_write = NULL;
283 		res = ccw_device_start(raw->cdev, req->ccws,
284 				       (unsigned long) req, 0, 0);
285 		if (res != 0) {
286 			/* do_IO failed, put request back to queue */
287 			raw->queued_write = req;
288 		} else {
289 			raw->flags |= RAW3215_WORKING;
290 		}
291 	}
292 }
293 
294 /*
295  * Function to start a delayed output after RAW3215_TIMEOUT seconds
296  */
297 static void
298 raw3215_timeout(unsigned long __data)
299 {
300 	struct raw3215_info *raw = (struct raw3215_info *) __data;
301 	unsigned long flags;
302 
303 	spin_lock_irqsave(raw->lock, flags);
304 	if (raw->flags & RAW3215_TIMER_RUNS) {
305 		del_timer(&raw->timer);
306 		raw->flags &= ~RAW3215_TIMER_RUNS;
307 		raw3215_mk_write_req(raw);
308 		raw3215_start_io(raw);
309 	}
310 	spin_unlock_irqrestore(raw->lock, flags);
311 }
312 
313 /*
314  * Function to conditionally start an IO. A read is started immediately,
315  * a write is only started immediately if the flush flag is on or the
316  * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not
317  * done immediately a timer is started with a delay of RAW3215_TIMEOUT.
318  */
319 static inline void
320 raw3215_try_io(struct raw3215_info *raw)
321 {
322 	if (!(raw->flags & RAW3215_ACTIVE))
323 		return;
324 	if (raw->queued_read != NULL)
325 		raw3215_start_io(raw);
326 	else if (raw->queued_write != NULL) {
327 		if ((raw->queued_write->delayable == 0) ||
328 		    (raw->flags & RAW3215_FLUSHING)) {
329 			/* execute write requests bigger than minimum size */
330 			raw3215_start_io(raw);
331 			if (raw->flags & RAW3215_TIMER_RUNS) {
332 				del_timer(&raw->timer);
333 				raw->flags &= ~RAW3215_TIMER_RUNS;
334 			}
335 		} else if (!(raw->flags & RAW3215_TIMER_RUNS)) {
336 			/* delay small writes */
337 			init_timer(&raw->timer);
338 			raw->timer.expires = RAW3215_TIMEOUT + jiffies;
339 			raw->timer.data = (unsigned long) raw;
340 			raw->timer.function = raw3215_timeout;
341 			add_timer(&raw->timer);
342 			raw->flags |= RAW3215_TIMER_RUNS;
343 		}
344 	}
345 }
346 
347 /*
348  * The bottom half handler routine for 3215 devices. It tries to start
349  * the next IO and wakes up processes waiting on the tty.
350  */
351 static void
352 raw3215_tasklet(void *data)
353 {
354 	struct raw3215_info *raw;
355 	struct tty_struct *tty;
356 	unsigned long flags;
357 
358 	raw = (struct raw3215_info *) data;
359 	spin_lock_irqsave(raw->lock, flags);
360 	raw3215_mk_write_req(raw);
361 	raw3215_try_io(raw);
362 	spin_unlock_irqrestore(raw->lock, flags);
363 	/* Check for pending message from raw3215_irq */
364 	if (raw->message != NULL) {
365 		printk(raw->message, raw->msg_dstat, raw->msg_cstat);
366 		raw->message = NULL;
367 	}
368 	tty = raw->tty;
369 	if (tty != NULL &&
370 	    RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) {
371 	    	tty_wakeup(tty);
372 	}
373 }
374 
375 /*
376  * Interrupt routine, called from common io layer
377  */
378 static void
379 raw3215_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
380 {
381 	struct raw3215_info *raw;
382 	struct raw3215_req *req;
383 	struct tty_struct *tty;
384 	int cstat, dstat;
385 	int count, slen;
386 
387 	raw = cdev->dev.driver_data;
388 	req = (struct raw3215_req *) intparm;
389 	cstat = irb->scsw.cstat;
390 	dstat = irb->scsw.dstat;
391 	if (cstat != 0) {
392 		raw->message = KERN_WARNING
393 			"Got nonzero channel status in raw3215_irq "
394 			"(dev sts 0x%2x, sch sts 0x%2x)";
395 		raw->msg_dstat = dstat;
396 		raw->msg_cstat = cstat;
397 		tasklet_schedule(&raw->tasklet);
398 	}
399 	if (dstat & 0x01) { /* we got a unit exception */
400 		dstat &= ~0x01;	 /* we can ignore it */
401 	}
402 	switch (dstat) {
403 	case 0x80:
404 		if (cstat != 0)
405 			break;
406 		/* Attention interrupt, someone hit the enter key */
407 		raw3215_mk_read_req(raw);
408 		if (MACHINE_IS_P390)
409 			memset(raw->inbuf, 0, RAW3215_INBUF_SIZE);
410 		tasklet_schedule(&raw->tasklet);
411 		break;
412 	case 0x08:
413 	case 0x0C:
414 		/* Channel end interrupt. */
415 		if ((raw = req->info) == NULL)
416 			return;		     /* That shouldn't happen ... */
417 		if (req->type == RAW3215_READ) {
418 			/* store residual count, then wait for device end */
419 			req->residual = irb->scsw.count;
420 		}
421 		if (dstat == 0x08)
422 			break;
423 	case 0x04:
424 		/* Device end interrupt. */
425 		if ((raw = req->info) == NULL)
426 			return;		     /* That shouldn't happen ... */
427 		if (req->type == RAW3215_READ && raw->tty != NULL) {
428 			unsigned int cchar;
429 
430 			tty = raw->tty;
431 			count = 160 - req->residual;
432 			if (MACHINE_IS_P390) {
433 				slen = strnlen(raw->inbuf, RAW3215_INBUF_SIZE);
434 				if (count > slen)
435 					count = slen;
436 			} else
437 			EBCASC(raw->inbuf, count);
438 			cchar = ctrlchar_handle(raw->inbuf, count, tty);
439 			switch (cchar & CTRLCHAR_MASK) {
440 			case CTRLCHAR_SYSRQ:
441 				break;
442 
443 			case CTRLCHAR_CTRL:
444 				tty_insert_flip_char(tty, cchar, TTY_NORMAL);
445 				tty_flip_buffer_push(raw->tty);
446 				break;
447 
448 			case CTRLCHAR_NONE:
449 				if (count < 2 ||
450 				    (strncmp(raw->inbuf+count-2, "\252n", 2) &&
451 				     strncmp(raw->inbuf+count-2, "^n", 2)) ) {
452 					/* add the auto \n */
453 					raw->inbuf[count] = '\n';
454 					count++;
455 				} else
456 					count -= 2;
457 				tty_insert_flip_string(tty, raw->inbuf, count);
458 				tty_flip_buffer_push(raw->tty);
459 				break;
460 			}
461 		} else if (req->type == RAW3215_WRITE) {
462 			raw->count -= req->len;
463 			raw->written -= req->len;
464 		}
465 		raw->flags &= ~RAW3215_WORKING;
466 		raw3215_free_req(req);
467 		/* check for empty wait */
468 		if (waitqueue_active(&raw->empty_wait) &&
469 		    raw->queued_write == NULL &&
470 		    raw->queued_read == NULL) {
471 			wake_up_interruptible(&raw->empty_wait);
472 		}
473 		tasklet_schedule(&raw->tasklet);
474 		break;
475 	default:
476 		/* Strange interrupt, I'll do my best to clean up */
477 		if (req != NULL && req->type != RAW3215_FREE) {
478 			if (req->type == RAW3215_WRITE) {
479 				raw->count -= req->len;
480 				raw->written -= req->len;
481 			}
482 			raw->flags &= ~RAW3215_WORKING;
483 			raw3215_free_req(req);
484 		}
485 		raw->message = KERN_WARNING
486 			"Spurious interrupt in in raw3215_irq "
487 			"(dev sts 0x%2x, sch sts 0x%2x)";
488 		raw->msg_dstat = dstat;
489 		raw->msg_cstat = cstat;
490 		tasklet_schedule(&raw->tasklet);
491 	}
492 	return;
493 }
494 
495 /*
496  * Wait until length bytes are available int the output buffer.
497  * Has to be called with the s390irq lock held. Can be called
498  * disabled.
499  */
500 static void
501 raw3215_make_room(struct raw3215_info *raw, unsigned int length)
502 {
503 	while (RAW3215_BUFFER_SIZE - raw->count < length) {
504 		/* there might be a request pending */
505 		raw->flags |= RAW3215_FLUSHING;
506 		raw3215_mk_write_req(raw);
507 		raw3215_try_io(raw);
508 		raw->flags &= ~RAW3215_FLUSHING;
509 #ifdef CONFIG_TN3215_CONSOLE
510 		wait_cons_dev();
511 #endif
512 		/* Enough room freed up ? */
513 		if (RAW3215_BUFFER_SIZE - raw->count >= length)
514 			break;
515 		/* there might be another cpu waiting for the lock */
516 		spin_unlock(raw->lock);
517 		udelay(100);
518 		spin_lock(raw->lock);
519 	}
520 }
521 
522 /*
523  * String write routine for 3215 devices
524  */
525 static void
526 raw3215_write(struct raw3215_info *raw, const char *str, unsigned int length)
527 {
528 	unsigned long flags;
529 	int c, count;
530 
531 	while (length > 0) {
532 		spin_lock_irqsave(raw->lock, flags);
533 		count = (length > RAW3215_BUFFER_SIZE) ?
534 					     RAW3215_BUFFER_SIZE : length;
535 		length -= count;
536 
537 		raw3215_make_room(raw, count);
538 
539 		/* copy string to output buffer and convert it to EBCDIC */
540 		while (1) {
541 			c = min_t(int, count,
542 				  min(RAW3215_BUFFER_SIZE - raw->count,
543 				      RAW3215_BUFFER_SIZE - raw->head));
544 			if (c <= 0)
545 				break;
546 			memcpy(raw->buffer + raw->head, str, c);
547 			ASCEBC(raw->buffer + raw->head, c);
548 			raw->head = (raw->head + c) & (RAW3215_BUFFER_SIZE - 1);
549 			raw->count += c;
550 			raw->line_pos += c;
551 			str += c;
552 			count -= c;
553 		}
554 		if (!(raw->flags & RAW3215_WORKING)) {
555 			raw3215_mk_write_req(raw);
556 			/* start or queue request */
557 			raw3215_try_io(raw);
558 		}
559 		spin_unlock_irqrestore(raw->lock, flags);
560 	}
561 }
562 
563 /*
564  * Put character routine for 3215 devices
565  */
566 static void
567 raw3215_putchar(struct raw3215_info *raw, unsigned char ch)
568 {
569 	unsigned long flags;
570 	unsigned int length, i;
571 
572 	spin_lock_irqsave(raw->lock, flags);
573 	if (ch == '\t') {
574 		length = TAB_STOP_SIZE - (raw->line_pos%TAB_STOP_SIZE);
575 		raw->line_pos += length;
576 		ch = ' ';
577 	} else if (ch == '\n') {
578 		length = 1;
579 		raw->line_pos = 0;
580 	} else {
581 		length = 1;
582 		raw->line_pos++;
583 	}
584 	raw3215_make_room(raw, length);
585 
586 	for (i = 0; i < length; i++) {
587 		raw->buffer[raw->head] = (char) _ascebc[(int) ch];
588 		raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1);
589 		raw->count++;
590 	}
591 	if (!(raw->flags & RAW3215_WORKING)) {
592 		raw3215_mk_write_req(raw);
593 		/* start or queue request */
594 		raw3215_try_io(raw);
595 	}
596 	spin_unlock_irqrestore(raw->lock, flags);
597 }
598 
599 /*
600  * Flush routine, it simply sets the flush flag and tries to start
601  * pending IO.
602  */
603 static void
604 raw3215_flush_buffer(struct raw3215_info *raw)
605 {
606 	unsigned long flags;
607 
608 	spin_lock_irqsave(raw->lock, flags);
609 	if (raw->count > 0) {
610 		raw->flags |= RAW3215_FLUSHING;
611 		raw3215_try_io(raw);
612 		raw->flags &= ~RAW3215_FLUSHING;
613 	}
614 	spin_unlock_irqrestore(raw->lock, flags);
615 }
616 
617 /*
618  * Fire up a 3215 device.
619  */
620 static int
621 raw3215_startup(struct raw3215_info *raw)
622 {
623 	unsigned long flags;
624 
625 	if (raw->flags & RAW3215_ACTIVE)
626 		return 0;
627 	raw->line_pos = 0;
628 	raw->flags |= RAW3215_ACTIVE;
629 	spin_lock_irqsave(raw->lock, flags);
630 	raw3215_try_io(raw);
631 	spin_unlock_irqrestore(raw->lock, flags);
632 
633 	return 0;
634 }
635 
636 /*
637  * Shutdown a 3215 device.
638  */
639 static void
640 raw3215_shutdown(struct raw3215_info *raw)
641 {
642 	DECLARE_WAITQUEUE(wait, current);
643 	unsigned long flags;
644 
645 	if (!(raw->flags & RAW3215_ACTIVE) || (raw->flags & RAW3215_FIXED))
646 		return;
647 	/* Wait for outstanding requests, then free irq */
648 	spin_lock_irqsave(raw->lock, flags);
649 	if ((raw->flags & RAW3215_WORKING) ||
650 	    raw->queued_write != NULL ||
651 	    raw->queued_read != NULL) {
652 		raw->flags |= RAW3215_CLOSING;
653 		add_wait_queue(&raw->empty_wait, &wait);
654 		set_current_state(TASK_INTERRUPTIBLE);
655 		spin_unlock_irqrestore(raw->lock, flags);
656 		schedule();
657 		spin_lock_irqsave(raw->lock, flags);
658 		remove_wait_queue(&raw->empty_wait, &wait);
659 		set_current_state(TASK_RUNNING);
660 		raw->flags &= ~(RAW3215_ACTIVE | RAW3215_CLOSING);
661 	}
662 	spin_unlock_irqrestore(raw->lock, flags);
663 }
664 
665 static int
666 raw3215_probe (struct ccw_device *cdev)
667 {
668 	struct raw3215_info *raw;
669 	int line;
670 
671 	raw = kmalloc(sizeof(struct raw3215_info) +
672 		      RAW3215_INBUF_SIZE, GFP_KERNEL|GFP_DMA);
673 	if (raw == NULL)
674 		return -ENOMEM;
675 
676 	spin_lock(&raw3215_device_lock);
677 	for (line = 0; line < NR_3215; line++) {
678 		if (!raw3215[line]) {
679 			raw3215[line] = raw;
680 			break;
681 		}
682 	}
683 	spin_unlock(&raw3215_device_lock);
684 	if (line == NR_3215) {
685 		kfree(raw);
686 		return -ENODEV;
687 	}
688 
689 	raw->cdev = cdev;
690 	raw->lock = get_ccwdev_lock(cdev);
691 	raw->inbuf = (char *) raw + sizeof(struct raw3215_info);
692 	memset(raw, 0, sizeof(struct raw3215_info));
693 	raw->buffer = (char *) kmalloc(RAW3215_BUFFER_SIZE,
694 				       GFP_KERNEL|GFP_DMA);
695 	if (raw->buffer == NULL) {
696 		spin_lock(&raw3215_device_lock);
697 		raw3215[line] = 0;
698 		spin_unlock(&raw3215_device_lock);
699 		kfree(raw);
700 		return -ENOMEM;
701 	}
702 	tasklet_init(&raw->tasklet,
703 		     (void (*)(unsigned long)) raw3215_tasklet,
704 		     (unsigned long) raw);
705 	init_waitqueue_head(&raw->empty_wait);
706 
707 	cdev->dev.driver_data = raw;
708 	cdev->handler = raw3215_irq;
709 
710 	return 0;
711 }
712 
713 static void
714 raw3215_remove (struct ccw_device *cdev)
715 {
716 	struct raw3215_info *raw;
717 
718 	ccw_device_set_offline(cdev);
719 	raw = cdev->dev.driver_data;
720 	if (raw) {
721 		cdev->dev.driver_data = NULL;
722 		kfree(raw->buffer);
723 		kfree(raw);
724 	}
725 }
726 
727 static int
728 raw3215_set_online (struct ccw_device *cdev)
729 {
730 	struct raw3215_info *raw;
731 
732 	raw = cdev->dev.driver_data;
733 	if (!raw)
734 		return -ENODEV;
735 
736 	return raw3215_startup(raw);
737 }
738 
739 static int
740 raw3215_set_offline (struct ccw_device *cdev)
741 {
742 	struct raw3215_info *raw;
743 
744 	raw = cdev->dev.driver_data;
745 	if (!raw)
746 		return -ENODEV;
747 
748 	raw3215_shutdown(raw);
749 
750 	return 0;
751 }
752 
753 static struct ccw_device_id raw3215_id[] = {
754 	{ CCW_DEVICE(0x3215, 0) },
755 	{ /* end of list */ },
756 };
757 
758 static struct ccw_driver raw3215_ccw_driver = {
759 	.name		= "3215",
760 	.owner		= THIS_MODULE,
761 	.ids		= raw3215_id,
762 	.probe		= &raw3215_probe,
763 	.remove		= &raw3215_remove,
764 	.set_online	= &raw3215_set_online,
765 	.set_offline	= &raw3215_set_offline,
766 };
767 
768 #ifdef CONFIG_TN3215_CONSOLE
769 /*
770  * Write a string to the 3215 console
771  */
772 static void
773 con3215_write(struct console *co, const char *str, unsigned int count)
774 {
775 	struct raw3215_info *raw;
776 	int i;
777 
778 	if (count <= 0)
779 		return;
780 	raw = raw3215[0];	/* console 3215 is the first one */
781 	while (count > 0) {
782 		for (i = 0; i < count; i++)
783 			if (str[i] == '\t' || str[i] == '\n')
784 				break;
785 		raw3215_write(raw, str, i);
786 		count -= i;
787 		str += i;
788 		if (count > 0) {
789 			raw3215_putchar(raw, *str);
790 			count--;
791 			str++;
792 		}
793 	}
794 }
795 
796 static struct tty_driver *con3215_device(struct console *c, int *index)
797 {
798 	*index = c->index;
799 	return tty3215_driver;
800 }
801 
802 /*
803  * panic() calls console_unblank before the system enters a
804  * disabled, endless loop.
805  */
806 static void
807 con3215_unblank(void)
808 {
809 	struct raw3215_info *raw;
810 	unsigned long flags;
811 
812 	raw = raw3215[0];  /* console 3215 is the first one */
813 	spin_lock_irqsave(raw->lock, flags);
814 	raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
815 	spin_unlock_irqrestore(raw->lock, flags);
816 }
817 
818 static int __init
819 con3215_consetup(struct console *co, char *options)
820 {
821 	return 0;
822 }
823 
824 /*
825  *  The console structure for the 3215 console
826  */
827 static struct console con3215 = {
828 	.name	 = "ttyS",
829 	.write	 = con3215_write,
830 	.device	 = con3215_device,
831 	.unblank = con3215_unblank,
832 	.setup	 = con3215_consetup,
833 	.flags	 = CON_PRINTBUFFER,
834 };
835 
836 /*
837  * 3215 console initialization code called from console_init().
838  * NOTE: This is called before kmalloc is available.
839  */
840 static int __init
841 con3215_init(void)
842 {
843 	struct ccw_device *cdev;
844 	struct raw3215_info *raw;
845 	struct raw3215_req *req;
846 	int i;
847 
848 	/* Check if 3215 is to be the console */
849 	if (!CONSOLE_IS_3215)
850 		return -ENODEV;
851 
852 	/* Set the console mode for VM */
853 	if (MACHINE_IS_VM) {
854 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
855 		cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
856 	}
857 
858 	/* allocate 3215 request structures */
859 	raw3215_freelist = NULL;
860 	spin_lock_init(&raw3215_freelist_lock);
861 	for (i = 0; i < NR_3215_REQ; i++) {
862 		req = (struct raw3215_req *) alloc_bootmem_low(sizeof(struct raw3215_req));
863 		req->next = raw3215_freelist;
864 		raw3215_freelist = req;
865 	}
866 
867 	cdev = ccw_device_probe_console();
868 	if (IS_ERR(cdev))
869 		return -ENODEV;
870 
871 	raw3215[0] = raw = (struct raw3215_info *)
872 		alloc_bootmem_low(sizeof(struct raw3215_info));
873 	memset(raw, 0, sizeof(struct raw3215_info));
874 	raw->buffer = (char *) alloc_bootmem_low(RAW3215_BUFFER_SIZE);
875 	raw->inbuf = (char *) alloc_bootmem_low(RAW3215_INBUF_SIZE);
876 	raw->cdev = cdev;
877 	raw->lock = get_ccwdev_lock(cdev);
878 	cdev->dev.driver_data = raw;
879 	cdev->handler = raw3215_irq;
880 
881 	raw->flags |= RAW3215_FIXED;
882 	tasklet_init(&raw->tasklet,
883 		     (void (*)(unsigned long)) raw3215_tasklet,
884 		     (unsigned long) raw);
885 	init_waitqueue_head(&raw->empty_wait);
886 
887 	/* Request the console irq */
888 	if (raw3215_startup(raw) != 0) {
889 		free_bootmem((unsigned long) raw->inbuf, RAW3215_INBUF_SIZE);
890 		free_bootmem((unsigned long) raw->buffer, RAW3215_BUFFER_SIZE);
891 		free_bootmem((unsigned long) raw, sizeof(struct raw3215_info));
892 		raw3215[0] = NULL;
893 		printk("Couldn't find a 3215 console device\n");
894 		return -ENODEV;
895 	}
896 	register_console(&con3215);
897 	return 0;
898 }
899 console_initcall(con3215_init);
900 #endif
901 
902 /*
903  * tty3215_open
904  *
905  * This routine is called whenever a 3215 tty is opened.
906  */
907 static int
908 tty3215_open(struct tty_struct *tty, struct file * filp)
909 {
910 	struct raw3215_info *raw;
911 	int retval, line;
912 
913 	line = tty->index;
914 	if ((line < 0) || (line >= NR_3215))
915 		return -ENODEV;
916 
917 	raw = raw3215[line];
918 	if (raw == NULL)
919 		return -ENODEV;
920 
921 	tty->driver_data = raw;
922 	raw->tty = tty;
923 
924 	tty->low_latency = 0;  /* don't use bottom half for pushing chars */
925 	/*
926 	 * Start up 3215 device
927 	 */
928 	retval = raw3215_startup(raw);
929 	if (retval)
930 		return retval;
931 
932 	return 0;
933 }
934 
935 /*
936  * tty3215_close()
937  *
938  * This routine is called when the 3215 tty is closed. We wait
939  * for the remaining request to be completed. Then we clean up.
940  */
941 static void
942 tty3215_close(struct tty_struct *tty, struct file * filp)
943 {
944 	struct raw3215_info *raw;
945 
946 	raw = (struct raw3215_info *) tty->driver_data;
947 	if (raw == NULL || tty->count > 1)
948 		return;
949 	tty->closing = 1;
950 	/* Shutdown the terminal */
951 	raw3215_shutdown(raw);
952 	tty->closing = 0;
953 	raw->tty = NULL;
954 }
955 
956 /*
957  * Returns the amount of free space in the output buffer.
958  */
959 static int
960 tty3215_write_room(struct tty_struct *tty)
961 {
962 	struct raw3215_info *raw;
963 
964 	raw = (struct raw3215_info *) tty->driver_data;
965 
966 	/* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */
967 	if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0)
968 		return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE;
969 	else
970 		return 0;
971 }
972 
973 /*
974  * String write routine for 3215 ttys
975  */
976 static int
977 tty3215_write(struct tty_struct * tty,
978 	      const unsigned char *buf, int count)
979 {
980 	struct raw3215_info *raw;
981 
982 	if (!tty)
983 		return 0;
984 	raw = (struct raw3215_info *) tty->driver_data;
985 	raw3215_write(raw, buf, count);
986 	return count;
987 }
988 
989 /*
990  * Put character routine for 3215 ttys
991  */
992 static void
993 tty3215_put_char(struct tty_struct *tty, unsigned char ch)
994 {
995 	struct raw3215_info *raw;
996 
997 	if (!tty)
998 		return;
999 	raw = (struct raw3215_info *) tty->driver_data;
1000 	raw3215_putchar(raw, ch);
1001 }
1002 
1003 static void
1004 tty3215_flush_chars(struct tty_struct *tty)
1005 {
1006 }
1007 
1008 /*
1009  * Returns the number of characters in the output buffer
1010  */
1011 static int
1012 tty3215_chars_in_buffer(struct tty_struct *tty)
1013 {
1014 	struct raw3215_info *raw;
1015 
1016 	raw = (struct raw3215_info *) tty->driver_data;
1017 	return raw->count;
1018 }
1019 
1020 static void
1021 tty3215_flush_buffer(struct tty_struct *tty)
1022 {
1023 	struct raw3215_info *raw;
1024 
1025 	raw = (struct raw3215_info *) tty->driver_data;
1026 	raw3215_flush_buffer(raw);
1027 	tty_wakeup(tty);
1028 }
1029 
1030 /*
1031  * Currently we don't have any io controls for 3215 ttys
1032  */
1033 static int
1034 tty3215_ioctl(struct tty_struct *tty, struct file * file,
1035 	      unsigned int cmd, unsigned long arg)
1036 {
1037 	if (tty->flags & (1 << TTY_IO_ERROR))
1038 		return -EIO;
1039 
1040 	switch (cmd) {
1041 	default:
1042 		return -ENOIOCTLCMD;
1043 	}
1044 	return 0;
1045 }
1046 
1047 /*
1048  * Disable reading from a 3215 tty
1049  */
1050 static void
1051 tty3215_throttle(struct tty_struct * tty)
1052 {
1053 	struct raw3215_info *raw;
1054 
1055 	raw = (struct raw3215_info *) tty->driver_data;
1056 	raw->flags |= RAW3215_THROTTLED;
1057 }
1058 
1059 /*
1060  * Enable reading from a 3215 tty
1061  */
1062 static void
1063 tty3215_unthrottle(struct tty_struct * tty)
1064 {
1065 	struct raw3215_info *raw;
1066 	unsigned long flags;
1067 
1068 	raw = (struct raw3215_info *) tty->driver_data;
1069 	if (raw->flags & RAW3215_THROTTLED) {
1070 		spin_lock_irqsave(raw->lock, flags);
1071 		raw->flags &= ~RAW3215_THROTTLED;
1072 		raw3215_try_io(raw);
1073 		spin_unlock_irqrestore(raw->lock, flags);
1074 	}
1075 }
1076 
1077 /*
1078  * Disable writing to a 3215 tty
1079  */
1080 static void
1081 tty3215_stop(struct tty_struct *tty)
1082 {
1083 	struct raw3215_info *raw;
1084 
1085 	raw = (struct raw3215_info *) tty->driver_data;
1086 	raw->flags |= RAW3215_STOPPED;
1087 }
1088 
1089 /*
1090  * Enable writing to a 3215 tty
1091  */
1092 static void
1093 tty3215_start(struct tty_struct *tty)
1094 {
1095 	struct raw3215_info *raw;
1096 	unsigned long flags;
1097 
1098 	raw = (struct raw3215_info *) tty->driver_data;
1099 	if (raw->flags & RAW3215_STOPPED) {
1100 		spin_lock_irqsave(raw->lock, flags);
1101 		raw->flags &= ~RAW3215_STOPPED;
1102 		raw3215_try_io(raw);
1103 		spin_unlock_irqrestore(raw->lock, flags);
1104 	}
1105 }
1106 
1107 static struct tty_operations tty3215_ops = {
1108 	.open = tty3215_open,
1109 	.close = tty3215_close,
1110 	.write = tty3215_write,
1111 	.put_char = tty3215_put_char,
1112 	.flush_chars = tty3215_flush_chars,
1113 	.write_room = tty3215_write_room,
1114 	.chars_in_buffer = tty3215_chars_in_buffer,
1115 	.flush_buffer = tty3215_flush_buffer,
1116 	.ioctl = tty3215_ioctl,
1117 	.throttle = tty3215_throttle,
1118 	.unthrottle = tty3215_unthrottle,
1119 	.stop = tty3215_stop,
1120 	.start = tty3215_start,
1121 };
1122 
1123 /*
1124  * 3215 tty registration code called from tty_init().
1125  * Most kernel services (incl. kmalloc) are available at this poimt.
1126  */
1127 int __init
1128 tty3215_init(void)
1129 {
1130 	struct tty_driver *driver;
1131 	int ret;
1132 
1133 	if (!CONSOLE_IS_3215)
1134 		return 0;
1135 
1136 	driver = alloc_tty_driver(NR_3215);
1137 	if (!driver)
1138 		return -ENOMEM;
1139 
1140 	ret = ccw_driver_register(&raw3215_ccw_driver);
1141 	if (ret) {
1142 		put_tty_driver(driver);
1143 		return ret;
1144 	}
1145 	/*
1146 	 * Initialize the tty_driver structure
1147 	 * Entries in tty3215_driver that are NOT initialized:
1148 	 * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
1149 	 */
1150 
1151 	driver->owner = THIS_MODULE;
1152 	driver->driver_name = "tty3215";
1153 	driver->name = "ttyS";
1154 	driver->major = TTY_MAJOR;
1155 	driver->minor_start = 64;
1156 	driver->type = TTY_DRIVER_TYPE_SYSTEM;
1157 	driver->subtype = SYSTEM_TYPE_TTY;
1158 	driver->init_termios = tty_std_termios;
1159 	driver->init_termios.c_iflag = IGNBRK | IGNPAR;
1160 	driver->init_termios.c_oflag = ONLCR | XTABS;
1161 	driver->init_termios.c_lflag = ISIG;
1162 	driver->flags = TTY_DRIVER_REAL_RAW;
1163 	tty_set_operations(driver, &tty3215_ops);
1164 	ret = tty_register_driver(driver);
1165 	if (ret) {
1166 		printk("Couldn't register tty3215 driver\n");
1167 		put_tty_driver(driver);
1168 		return ret;
1169 	}
1170 	tty3215_driver = driver;
1171 	return 0;
1172 }
1173 
1174 static void __exit
1175 tty3215_exit(void)
1176 {
1177 	tty_unregister_driver(tty3215_driver);
1178 	put_tty_driver(tty3215_driver);
1179 	ccw_driver_unregister(&raw3215_ccw_driver);
1180 }
1181 
1182 module_init(tty3215_init);
1183 module_exit(tty3215_exit);
1184