xref: /openbmc/linux/drivers/s390/char/con3215.c (revision b627b4ed)
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/module.h>
15 #include <linux/types.h>
16 #include <linux/kdev_t.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/vt_kern.h>
20 #include <linux/init.h>
21 #include <linux/console.h>
22 #include <linux/interrupt.h>
23 #include <linux/err.h>
24 #include <linux/reboot.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 raw3215_req *queued_read; /* pointer to queued read requests */
93 	struct raw3215_req *queued_write;/* pointer to queued write requests */
94 	wait_queue_head_t empty_wait; /* wait queue for flushing */
95 	struct timer_list timer;      /* timer for delayed output */
96 	int line_pos;		      /* position on the line (for tabs) */
97 	char ubuffer[80];	      /* copy_from_user buffer */
98 };
99 
100 /* array of 3215 devices structures */
101 static struct raw3215_info *raw3215[NR_3215];
102 /* spinlock to protect the raw3215 array */
103 static DEFINE_SPINLOCK(raw3215_device_lock);
104 /* list of free request structures */
105 static struct raw3215_req *raw3215_freelist;
106 /* spinlock to protect free list */
107 static spinlock_t raw3215_freelist_lock;
108 
109 static struct tty_driver *tty3215_driver;
110 
111 /*
112  * Get a request structure from the free list
113  */
114 static inline struct raw3215_req *
115 raw3215_alloc_req(void) {
116 	struct raw3215_req *req;
117 	unsigned long flags;
118 
119 	spin_lock_irqsave(&raw3215_freelist_lock, flags);
120 	req = raw3215_freelist;
121 	raw3215_freelist = req->next;
122 	spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
123 	return req;
124 }
125 
126 /*
127  * Put a request structure back to the free list
128  */
129 static inline void
130 raw3215_free_req(struct raw3215_req *req) {
131 	unsigned long flags;
132 
133 	if (req->type == RAW3215_FREE)
134 		return;		/* don't free a free request */
135 	req->type = RAW3215_FREE;
136 	spin_lock_irqsave(&raw3215_freelist_lock, flags);
137 	req->next = raw3215_freelist;
138 	raw3215_freelist = req;
139 	spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
140 }
141 
142 /*
143  * Set up a read request that reads up to 160 byte from the 3215 device.
144  * If there is a queued read request it is used, but that shouldn't happen
145  * because a 3215 terminal won't accept a new read before the old one is
146  * completed.
147  */
148 static void
149 raw3215_mk_read_req(struct raw3215_info *raw)
150 {
151 	struct raw3215_req *req;
152 	struct ccw1 *ccw;
153 
154 	/* there can only be ONE read request at a time */
155 	req = raw->queued_read;
156 	if (req == NULL) {
157 		/* no queued read request, use new req structure */
158 		req = raw3215_alloc_req();
159 		req->type = RAW3215_READ;
160 		req->info = raw;
161 		raw->queued_read = req;
162 	}
163 
164 	ccw = req->ccws;
165 	ccw->cmd_code = 0x0A; /* read inquiry */
166 	ccw->flags = 0x20;    /* ignore incorrect length */
167 	ccw->count = 160;
168 	ccw->cda = (__u32) __pa(raw->inbuf);
169 }
170 
171 /*
172  * Set up a write request with the information from the main structure.
173  * A ccw chain is created that writes as much as possible from the output
174  * buffer to the 3215 device. If a queued write exists it is replaced by
175  * the new, probably lengthened request.
176  */
177 static void
178 raw3215_mk_write_req(struct raw3215_info *raw)
179 {
180 	struct raw3215_req *req;
181 	struct ccw1 *ccw;
182 	int len, count, ix, lines;
183 
184 	if (raw->count <= raw->written)
185 		return;
186 	/* check if there is a queued write request */
187 	req = raw->queued_write;
188 	if (req == NULL) {
189 		/* no queued write request, use new req structure */
190 		req = raw3215_alloc_req();
191 		req->type = RAW3215_WRITE;
192 		req->info = raw;
193 		raw->queued_write = req;
194 	} else {
195 		raw->written -= req->len;
196 	}
197 
198 	ccw = req->ccws;
199 	req->start = (raw->head - raw->count + raw->written) &
200 		     (RAW3215_BUFFER_SIZE - 1);
201 	/*
202 	 * now we have to count newlines. We can at max accept
203 	 * RAW3215_MAX_NEWLINE newlines in a single ssch due to
204 	 * a restriction in VM
205 	 */
206 	lines = 0;
207 	ix = req->start;
208 	while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) {
209 		if (raw->buffer[ix] == 0x15)
210 			lines++;
211 		ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
212 	}
213 	len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1;
214 	if (len > RAW3215_MAX_BYTES)
215 		len = RAW3215_MAX_BYTES;
216 	req->len = len;
217 	raw->written += len;
218 
219 	/* set the indication if we should try to enlarge this request */
220 	req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE);
221 
222 	ix = req->start;
223 	while (len > 0) {
224 		if (ccw > req->ccws)
225 			ccw[-1].flags |= 0x40; /* use command chaining */
226 		ccw->cmd_code = 0x01; /* write, auto carrier return */
227 		ccw->flags = 0x20;    /* ignore incorrect length ind.  */
228 		ccw->cda =
229 			(__u32) __pa(raw->buffer + ix);
230 		count = len;
231 		if (ix + count > RAW3215_BUFFER_SIZE)
232 			count = RAW3215_BUFFER_SIZE - ix;
233 		ccw->count = count;
234 		len -= count;
235 		ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1);
236 		ccw++;
237 	}
238 	/*
239 	 * Add a NOP to the channel program. 3215 devices are purely
240 	 * emulated and its much better to avoid the channel end
241 	 * interrupt in this case.
242 	 */
243 	if (ccw > req->ccws)
244 		ccw[-1].flags |= 0x40; /* use command chaining */
245 	ccw->cmd_code = 0x03; /* NOP */
246 	ccw->flags = 0;
247 	ccw->cda = 0;
248 	ccw->count = 1;
249 }
250 
251 /*
252  * Start a read or a write request
253  */
254 static void
255 raw3215_start_io(struct raw3215_info *raw)
256 {
257 	struct raw3215_req *req;
258 	int res;
259 
260 	req = raw->queued_read;
261 	if (req != NULL &&
262 	    !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) {
263 		/* dequeue request */
264 		raw->queued_read = NULL;
265 		res = ccw_device_start(raw->cdev, req->ccws,
266 				       (unsigned long) req, 0, 0);
267 		if (res != 0) {
268 			/* do_IO failed, put request back to queue */
269 			raw->queued_read = req;
270 		} else {
271 			raw->flags |= RAW3215_WORKING;
272 		}
273 	}
274 	req = raw->queued_write;
275 	if (req != NULL &&
276 	    !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) {
277 		/* dequeue request */
278 		raw->queued_write = NULL;
279 		res = ccw_device_start(raw->cdev, req->ccws,
280 				       (unsigned long) req, 0, 0);
281 		if (res != 0) {
282 			/* do_IO failed, put request back to queue */
283 			raw->queued_write = req;
284 		} else {
285 			raw->flags |= RAW3215_WORKING;
286 		}
287 	}
288 }
289 
290 /*
291  * Function to start a delayed output after RAW3215_TIMEOUT seconds
292  */
293 static void
294 raw3215_timeout(unsigned long __data)
295 {
296 	struct raw3215_info *raw = (struct raw3215_info *) __data;
297 	unsigned long flags;
298 
299 	spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
300 	if (raw->flags & RAW3215_TIMER_RUNS) {
301 		del_timer(&raw->timer);
302 		raw->flags &= ~RAW3215_TIMER_RUNS;
303 		raw3215_mk_write_req(raw);
304 		raw3215_start_io(raw);
305 	}
306 	spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
307 }
308 
309 /*
310  * Function to conditionally start an IO. A read is started immediately,
311  * a write is only started immediately if the flush flag is on or the
312  * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not
313  * done immediately a timer is started with a delay of RAW3215_TIMEOUT.
314  */
315 static inline void
316 raw3215_try_io(struct raw3215_info *raw)
317 {
318 	if (!(raw->flags & RAW3215_ACTIVE))
319 		return;
320 	if (raw->queued_read != NULL)
321 		raw3215_start_io(raw);
322 	else if (raw->queued_write != NULL) {
323 		if ((raw->queued_write->delayable == 0) ||
324 		    (raw->flags & RAW3215_FLUSHING)) {
325 			/* execute write requests bigger than minimum size */
326 			raw3215_start_io(raw);
327 			if (raw->flags & RAW3215_TIMER_RUNS) {
328 				del_timer(&raw->timer);
329 				raw->flags &= ~RAW3215_TIMER_RUNS;
330 			}
331 		} else if (!(raw->flags & RAW3215_TIMER_RUNS)) {
332 			/* delay small writes */
333 			init_timer(&raw->timer);
334 			raw->timer.expires = RAW3215_TIMEOUT + jiffies;
335 			raw->timer.data = (unsigned long) raw;
336 			raw->timer.function = raw3215_timeout;
337 			add_timer(&raw->timer);
338 			raw->flags |= RAW3215_TIMER_RUNS;
339 		}
340 	}
341 }
342 
343 /*
344  * Try to start the next IO and wake up processes waiting on the tty.
345  */
346 static void raw3215_next_io(struct raw3215_info *raw)
347 {
348 	struct tty_struct *tty;
349 
350 	raw3215_mk_write_req(raw);
351 	raw3215_try_io(raw);
352 	tty = raw->tty;
353 	if (tty != NULL &&
354 	    RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) {
355 	    	tty_wakeup(tty);
356 	}
357 }
358 
359 /*
360  * Interrupt routine, called from common io layer
361  */
362 static void
363 raw3215_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
364 {
365 	struct raw3215_info *raw;
366 	struct raw3215_req *req;
367 	struct tty_struct *tty;
368 	int cstat, dstat;
369 	int count;
370 
371 	raw = cdev->dev.driver_data;
372 	req = (struct raw3215_req *) intparm;
373 	cstat = irb->scsw.cmd.cstat;
374 	dstat = irb->scsw.cmd.dstat;
375 	if (cstat != 0)
376 		raw3215_next_io(raw);
377 	if (dstat & 0x01) { /* we got a unit exception */
378 		dstat &= ~0x01;	 /* we can ignore it */
379 	}
380 	switch (dstat) {
381 	case 0x80:
382 		if (cstat != 0)
383 			break;
384 		/* Attention interrupt, someone hit the enter key */
385 		raw3215_mk_read_req(raw);
386 		raw3215_next_io(raw);
387 		break;
388 	case 0x08:
389 	case 0x0C:
390 		/* Channel end interrupt. */
391 		if ((raw = req->info) == NULL)
392 			return;		     /* That shouldn't happen ... */
393 		if (req->type == RAW3215_READ) {
394 			/* store residual count, then wait for device end */
395 			req->residual = irb->scsw.cmd.count;
396 		}
397 		if (dstat == 0x08)
398 			break;
399 	case 0x04:
400 		/* Device end interrupt. */
401 		if ((raw = req->info) == NULL)
402 			return;		     /* That shouldn't happen ... */
403 		if (req->type == RAW3215_READ && raw->tty != NULL) {
404 			unsigned int cchar;
405 
406 			tty = raw->tty;
407 			count = 160 - req->residual;
408 			EBCASC(raw->inbuf, count);
409 			cchar = ctrlchar_handle(raw->inbuf, count, tty);
410 			switch (cchar & CTRLCHAR_MASK) {
411 			case CTRLCHAR_SYSRQ:
412 				break;
413 
414 			case CTRLCHAR_CTRL:
415 				tty_insert_flip_char(tty, cchar, TTY_NORMAL);
416 				tty_flip_buffer_push(raw->tty);
417 				break;
418 
419 			case CTRLCHAR_NONE:
420 				if (count < 2 ||
421 				    (strncmp(raw->inbuf+count-2, "\252n", 2) &&
422 				     strncmp(raw->inbuf+count-2, "^n", 2)) ) {
423 					/* add the auto \n */
424 					raw->inbuf[count] = '\n';
425 					count++;
426 				} else
427 					count -= 2;
428 				tty_insert_flip_string(tty, raw->inbuf, count);
429 				tty_flip_buffer_push(raw->tty);
430 				break;
431 			}
432 		} else if (req->type == RAW3215_WRITE) {
433 			raw->count -= req->len;
434 			raw->written -= req->len;
435 		}
436 		raw->flags &= ~RAW3215_WORKING;
437 		raw3215_free_req(req);
438 		/* check for empty wait */
439 		if (waitqueue_active(&raw->empty_wait) &&
440 		    raw->queued_write == NULL &&
441 		    raw->queued_read == NULL) {
442 			wake_up_interruptible(&raw->empty_wait);
443 		}
444 		raw3215_next_io(raw);
445 		break;
446 	default:
447 		/* Strange interrupt, I'll do my best to clean up */
448 		if (req != NULL && req->type != RAW3215_FREE) {
449 			if (req->type == RAW3215_WRITE) {
450 				raw->count -= req->len;
451 				raw->written -= req->len;
452 			}
453 			raw->flags &= ~RAW3215_WORKING;
454 			raw3215_free_req(req);
455 		}
456 		raw3215_next_io(raw);
457 	}
458 	return;
459 }
460 
461 /*
462  * Wait until length bytes are available int the output buffer.
463  * Has to be called with the s390irq lock held. Can be called
464  * disabled.
465  */
466 static void
467 raw3215_make_room(struct raw3215_info *raw, unsigned int length)
468 {
469 	while (RAW3215_BUFFER_SIZE - raw->count < length) {
470 		/* there might be a request pending */
471 		raw->flags |= RAW3215_FLUSHING;
472 		raw3215_mk_write_req(raw);
473 		raw3215_try_io(raw);
474 		raw->flags &= ~RAW3215_FLUSHING;
475 #ifdef CONFIG_TN3215_CONSOLE
476 		wait_cons_dev();
477 #endif
478 		/* Enough room freed up ? */
479 		if (RAW3215_BUFFER_SIZE - raw->count >= length)
480 			break;
481 		/* there might be another cpu waiting for the lock */
482 		spin_unlock(get_ccwdev_lock(raw->cdev));
483 		udelay(100);
484 		spin_lock(get_ccwdev_lock(raw->cdev));
485 	}
486 }
487 
488 /*
489  * String write routine for 3215 devices
490  */
491 static void
492 raw3215_write(struct raw3215_info *raw, const char *str, unsigned int length)
493 {
494 	unsigned long flags;
495 	int c, count;
496 
497 	while (length > 0) {
498 		spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
499 		count = (length > RAW3215_BUFFER_SIZE) ?
500 					     RAW3215_BUFFER_SIZE : length;
501 		length -= count;
502 
503 		raw3215_make_room(raw, count);
504 
505 		/* copy string to output buffer and convert it to EBCDIC */
506 		while (1) {
507 			c = min_t(int, count,
508 				  min(RAW3215_BUFFER_SIZE - raw->count,
509 				      RAW3215_BUFFER_SIZE - raw->head));
510 			if (c <= 0)
511 				break;
512 			memcpy(raw->buffer + raw->head, str, c);
513 			ASCEBC(raw->buffer + raw->head, c);
514 			raw->head = (raw->head + c) & (RAW3215_BUFFER_SIZE - 1);
515 			raw->count += c;
516 			raw->line_pos += c;
517 			str += c;
518 			count -= c;
519 		}
520 		if (!(raw->flags & RAW3215_WORKING)) {
521 			raw3215_mk_write_req(raw);
522 			/* start or queue request */
523 			raw3215_try_io(raw);
524 		}
525 		spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
526 	}
527 }
528 
529 /*
530  * Put character routine for 3215 devices
531  */
532 static void
533 raw3215_putchar(struct raw3215_info *raw, unsigned char ch)
534 {
535 	unsigned long flags;
536 	unsigned int length, i;
537 
538 	spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
539 	if (ch == '\t') {
540 		length = TAB_STOP_SIZE - (raw->line_pos%TAB_STOP_SIZE);
541 		raw->line_pos += length;
542 		ch = ' ';
543 	} else if (ch == '\n') {
544 		length = 1;
545 		raw->line_pos = 0;
546 	} else {
547 		length = 1;
548 		raw->line_pos++;
549 	}
550 	raw3215_make_room(raw, length);
551 
552 	for (i = 0; i < length; i++) {
553 		raw->buffer[raw->head] = (char) _ascebc[(int) ch];
554 		raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1);
555 		raw->count++;
556 	}
557 	if (!(raw->flags & RAW3215_WORKING)) {
558 		raw3215_mk_write_req(raw);
559 		/* start or queue request */
560 		raw3215_try_io(raw);
561 	}
562 	spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
563 }
564 
565 /*
566  * Flush routine, it simply sets the flush flag and tries to start
567  * pending IO.
568  */
569 static void
570 raw3215_flush_buffer(struct raw3215_info *raw)
571 {
572 	unsigned long flags;
573 
574 	spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
575 	if (raw->count > 0) {
576 		raw->flags |= RAW3215_FLUSHING;
577 		raw3215_try_io(raw);
578 		raw->flags &= ~RAW3215_FLUSHING;
579 	}
580 	spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
581 }
582 
583 /*
584  * Fire up a 3215 device.
585  */
586 static int
587 raw3215_startup(struct raw3215_info *raw)
588 {
589 	unsigned long flags;
590 
591 	if (raw->flags & RAW3215_ACTIVE)
592 		return 0;
593 	raw->line_pos = 0;
594 	raw->flags |= RAW3215_ACTIVE;
595 	spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
596 	raw3215_try_io(raw);
597 	spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
598 
599 	return 0;
600 }
601 
602 /*
603  * Shutdown a 3215 device.
604  */
605 static void
606 raw3215_shutdown(struct raw3215_info *raw)
607 {
608 	DECLARE_WAITQUEUE(wait, current);
609 	unsigned long flags;
610 
611 	if (!(raw->flags & RAW3215_ACTIVE) || (raw->flags & RAW3215_FIXED))
612 		return;
613 	/* Wait for outstanding requests, then free irq */
614 	spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
615 	if ((raw->flags & RAW3215_WORKING) ||
616 	    raw->queued_write != NULL ||
617 	    raw->queued_read != NULL) {
618 		raw->flags |= RAW3215_CLOSING;
619 		add_wait_queue(&raw->empty_wait, &wait);
620 		set_current_state(TASK_INTERRUPTIBLE);
621 		spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
622 		schedule();
623 		spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
624 		remove_wait_queue(&raw->empty_wait, &wait);
625 		set_current_state(TASK_RUNNING);
626 		raw->flags &= ~(RAW3215_ACTIVE | RAW3215_CLOSING);
627 	}
628 	spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
629 }
630 
631 static int
632 raw3215_probe (struct ccw_device *cdev)
633 {
634 	struct raw3215_info *raw;
635 	int line;
636 
637 	/* Console is special. */
638 	if (raw3215[0] && (cdev->dev.driver_data == raw3215[0]))
639 		return 0;
640 	raw = kmalloc(sizeof(struct raw3215_info) +
641 		      RAW3215_INBUF_SIZE, GFP_KERNEL|GFP_DMA);
642 	if (raw == NULL)
643 		return -ENOMEM;
644 
645 	spin_lock(&raw3215_device_lock);
646 	for (line = 0; line < NR_3215; line++) {
647 		if (!raw3215[line]) {
648 			raw3215[line] = raw;
649 			break;
650 		}
651 	}
652 	spin_unlock(&raw3215_device_lock);
653 	if (line == NR_3215) {
654 		kfree(raw);
655 		return -ENODEV;
656 	}
657 
658 	raw->cdev = cdev;
659 	raw->inbuf = (char *) raw + sizeof(struct raw3215_info);
660 	memset(raw, 0, sizeof(struct raw3215_info));
661 	raw->buffer = kmalloc(RAW3215_BUFFER_SIZE,
662 				       GFP_KERNEL|GFP_DMA);
663 	if (raw->buffer == NULL) {
664 		spin_lock(&raw3215_device_lock);
665 		raw3215[line] = NULL;
666 		spin_unlock(&raw3215_device_lock);
667 		kfree(raw);
668 		return -ENOMEM;
669 	}
670 	init_waitqueue_head(&raw->empty_wait);
671 
672 	cdev->dev.driver_data = raw;
673 	cdev->handler = raw3215_irq;
674 
675 	return 0;
676 }
677 
678 static void
679 raw3215_remove (struct ccw_device *cdev)
680 {
681 	struct raw3215_info *raw;
682 
683 	ccw_device_set_offline(cdev);
684 	raw = cdev->dev.driver_data;
685 	if (raw) {
686 		cdev->dev.driver_data = NULL;
687 		kfree(raw->buffer);
688 		kfree(raw);
689 	}
690 }
691 
692 static int
693 raw3215_set_online (struct ccw_device *cdev)
694 {
695 	struct raw3215_info *raw;
696 
697 	raw = cdev->dev.driver_data;
698 	if (!raw)
699 		return -ENODEV;
700 
701 	return raw3215_startup(raw);
702 }
703 
704 static int
705 raw3215_set_offline (struct ccw_device *cdev)
706 {
707 	struct raw3215_info *raw;
708 
709 	raw = cdev->dev.driver_data;
710 	if (!raw)
711 		return -ENODEV;
712 
713 	raw3215_shutdown(raw);
714 
715 	return 0;
716 }
717 
718 static struct ccw_device_id raw3215_id[] = {
719 	{ CCW_DEVICE(0x3215, 0) },
720 	{ /* end of list */ },
721 };
722 
723 static struct ccw_driver raw3215_ccw_driver = {
724 	.name		= "3215",
725 	.owner		= THIS_MODULE,
726 	.ids		= raw3215_id,
727 	.probe		= &raw3215_probe,
728 	.remove		= &raw3215_remove,
729 	.set_online	= &raw3215_set_online,
730 	.set_offline	= &raw3215_set_offline,
731 };
732 
733 #ifdef CONFIG_TN3215_CONSOLE
734 /*
735  * Write a string to the 3215 console
736  */
737 static void
738 con3215_write(struct console *co, const char *str, unsigned int count)
739 {
740 	struct raw3215_info *raw;
741 	int i;
742 
743 	if (count <= 0)
744 		return;
745 	raw = raw3215[0];	/* console 3215 is the first one */
746 	while (count > 0) {
747 		for (i = 0; i < count; i++)
748 			if (str[i] == '\t' || str[i] == '\n')
749 				break;
750 		raw3215_write(raw, str, i);
751 		count -= i;
752 		str += i;
753 		if (count > 0) {
754 			raw3215_putchar(raw, *str);
755 			count--;
756 			str++;
757 		}
758 	}
759 }
760 
761 static struct tty_driver *con3215_device(struct console *c, int *index)
762 {
763 	*index = c->index;
764 	return tty3215_driver;
765 }
766 
767 /*
768  * panic() calls con3215_flush through a panic_notifier
769  * before the system enters a disabled, endless loop.
770  */
771 static void
772 con3215_flush(void)
773 {
774 	struct raw3215_info *raw;
775 	unsigned long flags;
776 
777 	raw = raw3215[0];  /* console 3215 is the first one */
778 	spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
779 	raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
780 	spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
781 }
782 
783 static int con3215_notify(struct notifier_block *self,
784 			  unsigned long event, void *data)
785 {
786 	con3215_flush();
787 	return NOTIFY_OK;
788 }
789 
790 static struct notifier_block on_panic_nb = {
791 	.notifier_call = con3215_notify,
792 	.priority = 0,
793 };
794 
795 static struct notifier_block on_reboot_nb = {
796 	.notifier_call = con3215_notify,
797 	.priority = 0,
798 };
799 
800 /*
801  *  The console structure for the 3215 console
802  */
803 static struct console con3215 = {
804 	.name	 = "ttyS",
805 	.write	 = con3215_write,
806 	.device	 = con3215_device,
807 	.flags	 = CON_PRINTBUFFER,
808 };
809 
810 /*
811  * 3215 console initialization code called from console_init().
812  * NOTE: This is called before kmalloc is available.
813  */
814 static int __init
815 con3215_init(void)
816 {
817 	struct ccw_device *cdev;
818 	struct raw3215_info *raw;
819 	struct raw3215_req *req;
820 	int i;
821 
822 	/* Check if 3215 is to be the console */
823 	if (!CONSOLE_IS_3215)
824 		return -ENODEV;
825 
826 	/* Set the console mode for VM */
827 	if (MACHINE_IS_VM) {
828 		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
829 		cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
830 	}
831 
832 	/* allocate 3215 request structures */
833 	raw3215_freelist = NULL;
834 	spin_lock_init(&raw3215_freelist_lock);
835 	for (i = 0; i < NR_3215_REQ; i++) {
836 		req = (struct raw3215_req *) alloc_bootmem_low(sizeof(struct raw3215_req));
837 		req->next = raw3215_freelist;
838 		raw3215_freelist = req;
839 	}
840 
841 	cdev = ccw_device_probe_console();
842 	if (IS_ERR(cdev))
843 		return -ENODEV;
844 
845 	raw3215[0] = raw = (struct raw3215_info *)
846 		alloc_bootmem_low(sizeof(struct raw3215_info));
847 	memset(raw, 0, sizeof(struct raw3215_info));
848 	raw->buffer = (char *) alloc_bootmem_low(RAW3215_BUFFER_SIZE);
849 	raw->inbuf = (char *) alloc_bootmem_low(RAW3215_INBUF_SIZE);
850 	raw->cdev = cdev;
851 	cdev->dev.driver_data = raw;
852 	cdev->handler = raw3215_irq;
853 
854 	raw->flags |= RAW3215_FIXED;
855 	init_waitqueue_head(&raw->empty_wait);
856 
857 	/* Request the console irq */
858 	if (raw3215_startup(raw) != 0) {
859 		free_bootmem((unsigned long) raw->inbuf, RAW3215_INBUF_SIZE);
860 		free_bootmem((unsigned long) raw->buffer, RAW3215_BUFFER_SIZE);
861 		free_bootmem((unsigned long) raw, sizeof(struct raw3215_info));
862 		raw3215[0] = NULL;
863 		return -ENODEV;
864 	}
865 	atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);
866 	register_reboot_notifier(&on_reboot_nb);
867 	register_console(&con3215);
868 	return 0;
869 }
870 console_initcall(con3215_init);
871 #endif
872 
873 /*
874  * tty3215_open
875  *
876  * This routine is called whenever a 3215 tty is opened.
877  */
878 static int
879 tty3215_open(struct tty_struct *tty, struct file * filp)
880 {
881 	struct raw3215_info *raw;
882 	int retval, line;
883 
884 	line = tty->index;
885 	if ((line < 0) || (line >= NR_3215))
886 		return -ENODEV;
887 
888 	raw = raw3215[line];
889 	if (raw == NULL)
890 		return -ENODEV;
891 
892 	tty->driver_data = raw;
893 	raw->tty = tty;
894 
895 	tty->low_latency = 0;  /* don't use bottom half for pushing chars */
896 	/*
897 	 * Start up 3215 device
898 	 */
899 	retval = raw3215_startup(raw);
900 	if (retval)
901 		return retval;
902 
903 	return 0;
904 }
905 
906 /*
907  * tty3215_close()
908  *
909  * This routine is called when the 3215 tty is closed. We wait
910  * for the remaining request to be completed. Then we clean up.
911  */
912 static void
913 tty3215_close(struct tty_struct *tty, struct file * filp)
914 {
915 	struct raw3215_info *raw;
916 
917 	raw = (struct raw3215_info *) tty->driver_data;
918 	if (raw == NULL || tty->count > 1)
919 		return;
920 	tty->closing = 1;
921 	/* Shutdown the terminal */
922 	raw3215_shutdown(raw);
923 	tty->closing = 0;
924 	raw->tty = NULL;
925 }
926 
927 /*
928  * Returns the amount of free space in the output buffer.
929  */
930 static int
931 tty3215_write_room(struct tty_struct *tty)
932 {
933 	struct raw3215_info *raw;
934 
935 	raw = (struct raw3215_info *) tty->driver_data;
936 
937 	/* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */
938 	if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0)
939 		return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE;
940 	else
941 		return 0;
942 }
943 
944 /*
945  * String write routine for 3215 ttys
946  */
947 static int
948 tty3215_write(struct tty_struct * tty,
949 	      const unsigned char *buf, int count)
950 {
951 	struct raw3215_info *raw;
952 
953 	if (!tty)
954 		return 0;
955 	raw = (struct raw3215_info *) tty->driver_data;
956 	raw3215_write(raw, buf, count);
957 	return count;
958 }
959 
960 /*
961  * Put character routine for 3215 ttys
962  */
963 static int
964 tty3215_put_char(struct tty_struct *tty, unsigned char ch)
965 {
966 	struct raw3215_info *raw;
967 
968 	if (!tty)
969 		return 0;
970 	raw = (struct raw3215_info *) tty->driver_data;
971 	raw3215_putchar(raw, ch);
972 	return 1;
973 }
974 
975 static void
976 tty3215_flush_chars(struct tty_struct *tty)
977 {
978 }
979 
980 /*
981  * Returns the number of characters in the output buffer
982  */
983 static int
984 tty3215_chars_in_buffer(struct tty_struct *tty)
985 {
986 	struct raw3215_info *raw;
987 
988 	raw = (struct raw3215_info *) tty->driver_data;
989 	return raw->count;
990 }
991 
992 static void
993 tty3215_flush_buffer(struct tty_struct *tty)
994 {
995 	struct raw3215_info *raw;
996 
997 	raw = (struct raw3215_info *) tty->driver_data;
998 	raw3215_flush_buffer(raw);
999 	tty_wakeup(tty);
1000 }
1001 
1002 /*
1003  * Currently we don't have any io controls for 3215 ttys
1004  */
1005 static int
1006 tty3215_ioctl(struct tty_struct *tty, struct file * file,
1007 	      unsigned int cmd, unsigned long arg)
1008 {
1009 	if (tty->flags & (1 << TTY_IO_ERROR))
1010 		return -EIO;
1011 
1012 	switch (cmd) {
1013 	default:
1014 		return -ENOIOCTLCMD;
1015 	}
1016 	return 0;
1017 }
1018 
1019 /*
1020  * Disable reading from a 3215 tty
1021  */
1022 static void
1023 tty3215_throttle(struct tty_struct * tty)
1024 {
1025 	struct raw3215_info *raw;
1026 
1027 	raw = (struct raw3215_info *) tty->driver_data;
1028 	raw->flags |= RAW3215_THROTTLED;
1029 }
1030 
1031 /*
1032  * Enable reading from a 3215 tty
1033  */
1034 static void
1035 tty3215_unthrottle(struct tty_struct * tty)
1036 {
1037 	struct raw3215_info *raw;
1038 	unsigned long flags;
1039 
1040 	raw = (struct raw3215_info *) tty->driver_data;
1041 	if (raw->flags & RAW3215_THROTTLED) {
1042 		spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
1043 		raw->flags &= ~RAW3215_THROTTLED;
1044 		raw3215_try_io(raw);
1045 		spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
1046 	}
1047 }
1048 
1049 /*
1050  * Disable writing to a 3215 tty
1051  */
1052 static void
1053 tty3215_stop(struct tty_struct *tty)
1054 {
1055 	struct raw3215_info *raw;
1056 
1057 	raw = (struct raw3215_info *) tty->driver_data;
1058 	raw->flags |= RAW3215_STOPPED;
1059 }
1060 
1061 /*
1062  * Enable writing to a 3215 tty
1063  */
1064 static void
1065 tty3215_start(struct tty_struct *tty)
1066 {
1067 	struct raw3215_info *raw;
1068 	unsigned long flags;
1069 
1070 	raw = (struct raw3215_info *) tty->driver_data;
1071 	if (raw->flags & RAW3215_STOPPED) {
1072 		spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
1073 		raw->flags &= ~RAW3215_STOPPED;
1074 		raw3215_try_io(raw);
1075 		spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
1076 	}
1077 }
1078 
1079 static const struct tty_operations tty3215_ops = {
1080 	.open = tty3215_open,
1081 	.close = tty3215_close,
1082 	.write = tty3215_write,
1083 	.put_char = tty3215_put_char,
1084 	.flush_chars = tty3215_flush_chars,
1085 	.write_room = tty3215_write_room,
1086 	.chars_in_buffer = tty3215_chars_in_buffer,
1087 	.flush_buffer = tty3215_flush_buffer,
1088 	.ioctl = tty3215_ioctl,
1089 	.throttle = tty3215_throttle,
1090 	.unthrottle = tty3215_unthrottle,
1091 	.stop = tty3215_stop,
1092 	.start = tty3215_start,
1093 };
1094 
1095 /*
1096  * 3215 tty registration code called from tty_init().
1097  * Most kernel services (incl. kmalloc) are available at this poimt.
1098  */
1099 static int __init
1100 tty3215_init(void)
1101 {
1102 	struct tty_driver *driver;
1103 	int ret;
1104 
1105 	if (!CONSOLE_IS_3215)
1106 		return 0;
1107 
1108 	driver = alloc_tty_driver(NR_3215);
1109 	if (!driver)
1110 		return -ENOMEM;
1111 
1112 	ret = ccw_driver_register(&raw3215_ccw_driver);
1113 	if (ret) {
1114 		put_tty_driver(driver);
1115 		return ret;
1116 	}
1117 	/*
1118 	 * Initialize the tty_driver structure
1119 	 * Entries in tty3215_driver that are NOT initialized:
1120 	 * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
1121 	 */
1122 
1123 	driver->owner = THIS_MODULE;
1124 	driver->driver_name = "tty3215";
1125 	driver->name = "ttyS";
1126 	driver->major = TTY_MAJOR;
1127 	driver->minor_start = 64;
1128 	driver->type = TTY_DRIVER_TYPE_SYSTEM;
1129 	driver->subtype = SYSTEM_TYPE_TTY;
1130 	driver->init_termios = tty_std_termios;
1131 	driver->init_termios.c_iflag = IGNBRK | IGNPAR;
1132 	driver->init_termios.c_oflag = ONLCR | XTABS;
1133 	driver->init_termios.c_lflag = ISIG;
1134 	driver->flags = TTY_DRIVER_REAL_RAW;
1135 	tty_set_operations(driver, &tty3215_ops);
1136 	ret = tty_register_driver(driver);
1137 	if (ret) {
1138 		put_tty_driver(driver);
1139 		return ret;
1140 	}
1141 	tty3215_driver = driver;
1142 	return 0;
1143 }
1144 
1145 static void __exit
1146 tty3215_exit(void)
1147 {
1148 	tty_unregister_driver(tty3215_driver);
1149 	put_tty_driver(tty3215_driver);
1150 	ccw_driver_unregister(&raw3215_ccw_driver);
1151 }
1152 
1153 module_init(tty3215_init);
1154 module_exit(tty3215_exit);
1155