Linux Audio

Check our new training course

Loading...
v3.5.6
  1/*
  2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
  3 * Licensed under the GPL
  4 */
  5
  6#include <linux/slab.h>
  7#include <linux/tty.h>
  8#include <linux/tty_flip.h>
  9#include "chan.h"
 10#include "os.h"
 11#include "irq_kern.h"
 12
 13#ifdef CONFIG_NOCONFIG_CHAN
 14static void *not_configged_init(char *str, int device,
 15				const struct chan_opts *opts)
 16{
 17	printk(KERN_ERR "Using a channel type which is configured out of "
 18	       "UML\n");
 19	return NULL;
 20}
 21
 22static int not_configged_open(int input, int output, int primary, void *data,
 23			      char **dev_out)
 24{
 25	printk(KERN_ERR "Using a channel type which is configured out of "
 26	       "UML\n");
 27	return -ENODEV;
 28}
 29
 30static void not_configged_close(int fd, void *data)
 31{
 32	printk(KERN_ERR "Using a channel type which is configured out of "
 33	       "UML\n");
 34}
 35
 36static int not_configged_read(int fd, char *c_out, void *data)
 37{
 38	printk(KERN_ERR "Using a channel type which is configured out of "
 39	       "UML\n");
 40	return -EIO;
 41}
 42
 43static int not_configged_write(int fd, const char *buf, int len, void *data)
 44{
 45	printk(KERN_ERR "Using a channel type which is configured out of "
 46	       "UML\n");
 47	return -EIO;
 48}
 49
 50static int not_configged_console_write(int fd, const char *buf, int len)
 51{
 52	printk(KERN_ERR "Using a channel type which is configured out of "
 53	       "UML\n");
 54	return -EIO;
 55}
 56
 57static int not_configged_window_size(int fd, void *data, unsigned short *rows,
 58				     unsigned short *cols)
 59{
 60	printk(KERN_ERR "Using a channel type which is configured out of "
 61	       "UML\n");
 62	return -ENODEV;
 63}
 64
 65static void not_configged_free(void *data)
 66{
 67	printk(KERN_ERR "Using a channel type which is configured out of "
 68	       "UML\n");
 69}
 70
 71static const struct chan_ops not_configged_ops = {
 72	.init		= not_configged_init,
 73	.open		= not_configged_open,
 74	.close		= not_configged_close,
 75	.read		= not_configged_read,
 76	.write		= not_configged_write,
 77	.console_write	= not_configged_console_write,
 78	.window_size	= not_configged_window_size,
 79	.free		= not_configged_free,
 80	.winch		= 0,
 81};
 82#endif /* CONFIG_NOCONFIG_CHAN */
 83
 84static void tty_receive_char(struct tty_struct *tty, char ch)
 85{
 86	if (tty == NULL)
 87		return;
 88
 89	if (I_IXON(tty) && !I_IXOFF(tty) && !tty->raw) {
 90		if (ch == STOP_CHAR(tty)) {
 91			stop_tty(tty);
 92			return;
 93		}
 94		else if (ch == START_CHAR(tty)) {
 95			start_tty(tty);
 96			return;
 97		}
 98	}
 99
100	tty_insert_flip_char(tty, ch, TTY_NORMAL);
101}
102
103static int open_one_chan(struct chan *chan)
104{
105	int fd, err;
106
107	if (chan->opened)
108		return 0;
109
110	if (chan->ops->open == NULL)
111		fd = 0;
112	else fd = (*chan->ops->open)(chan->input, chan->output, chan->primary,
113				     chan->data, &chan->dev);
114	if (fd < 0)
115		return fd;
116
117	err = os_set_fd_block(fd, 0);
118	if (err) {
119		(*chan->ops->close)(fd, chan->data);
120		return err;
121	}
122
123	chan->fd = fd;
124
125	chan->opened = 1;
126	return 0;
127}
128
129static int open_chan(struct list_head *chans)
130{
131	struct list_head *ele;
132	struct chan *chan;
133	int ret, err = 0;
134
135	list_for_each(ele, chans) {
136		chan = list_entry(ele, struct chan, list);
137		ret = open_one_chan(chan);
138		if (chan->primary)
139			err = ret;
140	}
141	return err;
142}
143
144void chan_enable_winch(struct chan *chan, struct tty_struct *tty)
145{
146	if (chan && chan->primary && chan->ops->winch)
147		register_winch(chan->fd, tty);
148}
149
150static void line_timer_cb(struct work_struct *work)
151{
152	struct line *line = container_of(work, struct line, task.work);
153
154	if (!line->throttled)
155		chan_interrupt(line, line->tty, line->driver->read_irq);
 
 
 
 
 
156}
157
158int enable_chan(struct line *line)
159{
160	struct list_head *ele;
161	struct chan *chan;
162	int err;
163
164	INIT_DELAYED_WORK(&line->task, line_timer_cb);
165
166	list_for_each(ele, &line->chan_list) {
167		chan = list_entry(ele, struct chan, list);
168		err = open_one_chan(chan);
169		if (err) {
170			if (chan->primary)
171				goto out_close;
172
173			continue;
174		}
175
176		if (chan->enabled)
177			continue;
178		err = line_setup_irq(chan->fd, chan->input, chan->output, line,
179				     chan);
180		if (err)
181			goto out_close;
182
183		chan->enabled = 1;
184	}
185
186	return 0;
187
188 out_close:
189	close_chan(line);
190	return err;
191}
192
193/* Items are added in IRQ context, when free_irq can't be called, and
194 * removed in process context, when it can.
195 * This handles interrupt sources which disappear, and which need to
196 * be permanently disabled.  This is discovered in IRQ context, but
197 * the freeing of the IRQ must be done later.
198 */
199static DEFINE_SPINLOCK(irqs_to_free_lock);
200static LIST_HEAD(irqs_to_free);
201
202void free_irqs(void)
203{
204	struct chan *chan;
205	LIST_HEAD(list);
206	struct list_head *ele;
207	unsigned long flags;
208
209	spin_lock_irqsave(&irqs_to_free_lock, flags);
210	list_splice_init(&irqs_to_free, &list);
211	spin_unlock_irqrestore(&irqs_to_free_lock, flags);
212
213	list_for_each(ele, &list) {
214		chan = list_entry(ele, struct chan, free_list);
215
216		if (chan->input && chan->enabled)
217			um_free_irq(chan->line->driver->read_irq, chan);
218		if (chan->output && chan->enabled)
219			um_free_irq(chan->line->driver->write_irq, chan);
220		chan->enabled = 0;
221	}
222}
223
224static void close_one_chan(struct chan *chan, int delay_free_irq)
225{
226	unsigned long flags;
227
228	if (!chan->opened)
229		return;
230
231	if (delay_free_irq) {
232		spin_lock_irqsave(&irqs_to_free_lock, flags);
233		list_add(&chan->free_list, &irqs_to_free);
234		spin_unlock_irqrestore(&irqs_to_free_lock, flags);
235	}
236	else {
237		if (chan->input && chan->enabled)
238			um_free_irq(chan->line->driver->read_irq, chan);
239		if (chan->output && chan->enabled)
240			um_free_irq(chan->line->driver->write_irq, chan);
241		chan->enabled = 0;
242	}
243	if (chan->ops->close != NULL)
244		(*chan->ops->close)(chan->fd, chan->data);
245
246	chan->opened = 0;
247	chan->fd = -1;
248}
249
250void close_chan(struct line *line)
251{
252	struct chan *chan;
253
254	/* Close in reverse order as open in case more than one of them
255	 * refers to the same device and they save and restore that device's
256	 * state.  Then, the first one opened will have the original state,
257	 * so it must be the last closed.
258	 */
259	list_for_each_entry_reverse(chan, &line->chan_list, list) {
260		close_one_chan(chan, 0);
261	}
262}
263
264void deactivate_chan(struct chan *chan, int irq)
265{
266	if (chan && chan->enabled)
267		deactivate_fd(chan->fd, irq);
 
 
 
 
 
 
 
268}
269
270void reactivate_chan(struct chan *chan, int irq)
271{
272	if (chan && chan->enabled)
273		reactivate_fd(chan->fd, irq);
 
 
 
 
 
 
 
274}
275
276int write_chan(struct chan *chan, const char *buf, int len,
277	       int write_irq)
278{
 
 
279	int n, ret = 0;
280
281	if (len == 0 || !chan || !chan->ops->write)
282		return 0;
283
284	n = chan->ops->write(chan->fd, buf, len, chan->data);
285	if (chan->primary) {
286		ret = n;
287		if ((ret == -EAGAIN) || ((ret >= 0) && (ret < len)))
288			reactivate_fd(chan->fd, write_irq);
 
 
 
 
 
 
289	}
290	return ret;
291}
292
293int console_write_chan(struct chan *chan, const char *buf, int len)
294{
 
 
295	int n, ret = 0;
296
297	if (!chan || !chan->ops->console_write)
298		return 0;
 
 
299
300	n = chan->ops->console_write(chan->fd, buf, len);
301	if (chan->primary)
302		ret = n;
 
303	return ret;
304}
305
306int console_open_chan(struct line *line, struct console *co)
307{
308	int err;
309
310	err = open_chan(&line->chan_list);
311	if (err)
312		return err;
313
314	printk(KERN_INFO "Console initialized on /dev/%s%d\n", co->name,
315	       co->index);
316	return 0;
317}
318
319int chan_window_size(struct line *line, unsigned short *rows_out,
320		      unsigned short *cols_out)
321{
 
322	struct chan *chan;
323
324	chan = line->chan_in;
325	if (chan && chan->primary) {
326		if (chan->ops->window_size == NULL)
327			return 0;
328		return chan->ops->window_size(chan->fd, chan->data,
329					      rows_out, cols_out);
330	}
331	chan = line->chan_out;
332	if (chan && chan->primary) {
333		if (chan->ops->window_size == NULL)
334			return 0;
335		return chan->ops->window_size(chan->fd, chan->data,
336					      rows_out, cols_out);
337	}
338	return 0;
339}
340
341static void free_one_chan(struct chan *chan)
342{
343	list_del(&chan->list);
344
345	close_one_chan(chan, 0);
346
347	if (chan->ops->free != NULL)
348		(*chan->ops->free)(chan->data);
349
350	if (chan->primary && chan->output)
351		ignore_sigio_fd(chan->fd);
352	kfree(chan);
353}
354
355static void free_chan(struct list_head *chans)
356{
357	struct list_head *ele, *next;
358	struct chan *chan;
359
360	list_for_each_safe(ele, next, chans) {
361		chan = list_entry(ele, struct chan, list);
362		free_one_chan(chan);
363	}
364}
365
366static int one_chan_config_string(struct chan *chan, char *str, int size,
367				  char **error_out)
368{
369	int n = 0;
370
371	if (chan == NULL) {
372		CONFIG_CHUNK(str, size, n, "none", 1);
373		return n;
374	}
375
376	CONFIG_CHUNK(str, size, n, chan->ops->type, 0);
377
378	if (chan->dev == NULL) {
379		CONFIG_CHUNK(str, size, n, "", 1);
380		return n;
381	}
382
383	CONFIG_CHUNK(str, size, n, ":", 0);
384	CONFIG_CHUNK(str, size, n, chan->dev, 0);
385
386	return n;
387}
388
389static int chan_pair_config_string(struct chan *in, struct chan *out,
390				   char *str, int size, char **error_out)
391{
392	int n;
393
394	n = one_chan_config_string(in, str, size, error_out);
395	str += n;
396	size -= n;
397
398	if (in == out) {
399		CONFIG_CHUNK(str, size, n, "", 1);
400		return n;
401	}
402
403	CONFIG_CHUNK(str, size, n, ",", 1);
404	n = one_chan_config_string(out, str, size, error_out);
405	str += n;
406	size -= n;
407	CONFIG_CHUNK(str, size, n, "", 1);
408
409	return n;
410}
411
412int chan_config_string(struct line *line, char *str, int size,
413		       char **error_out)
414{
415	struct chan *in = line->chan_in, *out = line->chan_out;
 
416
417	if (in && !in->primary)
418		in = NULL;
419	if (out && !out->primary)
420		out = NULL;
 
 
 
 
 
421
422	return chan_pair_config_string(in, out, str, size, error_out);
423}
424
425struct chan_type {
426	char *key;
427	const struct chan_ops *ops;
428};
429
430static const struct chan_type chan_table[] = {
431	{ "fd", &fd_ops },
432
433#ifdef CONFIG_NULL_CHAN
434	{ "null", &null_ops },
435#else
436	{ "null", &not_configged_ops },
437#endif
438
439#ifdef CONFIG_PORT_CHAN
440	{ "port", &port_ops },
441#else
442	{ "port", &not_configged_ops },
443#endif
444
445#ifdef CONFIG_PTY_CHAN
446	{ "pty", &pty_ops },
447	{ "pts", &pts_ops },
448#else
449	{ "pty", &not_configged_ops },
450	{ "pts", &not_configged_ops },
451#endif
452
453#ifdef CONFIG_TTY_CHAN
454	{ "tty", &tty_ops },
455#else
456	{ "tty", &not_configged_ops },
457#endif
458
459#ifdef CONFIG_XTERM_CHAN
460	{ "xterm", &xterm_ops },
461#else
462	{ "xterm", &not_configged_ops },
463#endif
464};
465
466static struct chan *parse_chan(struct line *line, char *str, int device,
467			       const struct chan_opts *opts, char **error_out)
468{
469	const struct chan_type *entry;
470	const struct chan_ops *ops;
471	struct chan *chan;
472	void *data;
473	int i;
474
475	ops = NULL;
476	data = NULL;
477	for(i = 0; i < ARRAY_SIZE(chan_table); i++) {
478		entry = &chan_table[i];
479		if (!strncmp(str, entry->key, strlen(entry->key))) {
480			ops = entry->ops;
481			str += strlen(entry->key);
482			break;
483		}
484	}
485	if (ops == NULL) {
486		*error_out = "No match for configured backends";
487		return NULL;
488	}
489
490	data = (*ops->init)(str, device, opts);
491	if (data == NULL) {
492		*error_out = "Configuration failed";
493		return NULL;
494	}
495
496	chan = kmalloc(sizeof(*chan), GFP_ATOMIC);
497	if (chan == NULL) {
498		*error_out = "Memory allocation failed";
499		return NULL;
500	}
501	*chan = ((struct chan) { .list	 	= LIST_HEAD_INIT(chan->list),
502				 .free_list 	=
503				 	LIST_HEAD_INIT(chan->free_list),
504				 .line		= line,
505				 .primary	= 1,
506				 .input		= 0,
507				 .output 	= 0,
508				 .opened  	= 0,
509				 .enabled  	= 0,
510				 .fd 		= -1,
511				 .ops 		= ops,
512				 .data 		= data });
513	return chan;
514}
515
516int parse_chan_pair(char *str, struct line *line, int device,
517		    const struct chan_opts *opts, char **error_out)
518{
519	struct list_head *chans = &line->chan_list;
520	struct chan *new;
521	char *in, *out;
522
523	if (!list_empty(chans)) {
524		line->chan_in = line->chan_out = NULL;
525		free_chan(chans);
526		INIT_LIST_HEAD(chans);
527	}
528
529	if (!str)
530		return 0;
531
532	out = strchr(str, ',');
533	if (out != NULL) {
534		in = str;
535		*out = '\0';
536		out++;
537		new = parse_chan(line, in, device, opts, error_out);
538		if (new == NULL)
539			return -1;
540
541		new->input = 1;
542		list_add(&new->list, chans);
543		line->chan_in = new;
544
545		new = parse_chan(line, out, device, opts, error_out);
546		if (new == NULL)
547			return -1;
548
549		list_add(&new->list, chans);
550		new->output = 1;
551		line->chan_out = new;
552	}
553	else {
554		new = parse_chan(line, str, device, opts, error_out);
555		if (new == NULL)
556			return -1;
557
558		list_add(&new->list, chans);
559		new->input = 1;
560		new->output = 1;
561		line->chan_in = line->chan_out = new;
562	}
563	return 0;
564}
565
566void chan_interrupt(struct line *line, struct tty_struct *tty, int irq)
 
567{
568	struct chan *chan = line->chan_in;
 
569	int err;
570	char c;
571
572	if (!chan || !chan->ops->read)
573		goto out;
574
575	do {
576		if (tty && !tty_buffer_request_room(tty, 1)) {
577			schedule_delayed_work(&line->task, 1);
578			goto out;
579		}
580		err = chan->ops->read(chan->fd, &c, chan->data);
581		if (err > 0)
582			tty_receive_char(tty, c);
583	} while (err > 0);
584
585	if (err == 0)
586		reactivate_fd(chan->fd, irq);
587	if (err == -EIO) {
588		if (chan->primary) {
589			if (tty != NULL)
590				tty_hangup(tty);
591			if (line->chan_out != chan)
592				close_one_chan(line->chan_out, 1);
 
 
 
593		}
594		close_one_chan(chan, 1);
595		if (chan->primary)
596			return;
597	}
598 out:
599	if (tty)
600		tty_flip_buffer_push(tty);
601}
v3.1
  1/*
  2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
  3 * Licensed under the GPL
  4 */
  5
  6#include <linux/slab.h>
  7#include <linux/tty.h>
  8#include <linux/tty_flip.h>
  9#include "chan_kern.h"
 10#include "os.h"
 
 11
 12#ifdef CONFIG_NOCONFIG_CHAN
 13static void *not_configged_init(char *str, int device,
 14				const struct chan_opts *opts)
 15{
 16	printk(KERN_ERR "Using a channel type which is configured out of "
 17	       "UML\n");
 18	return NULL;
 19}
 20
 21static int not_configged_open(int input, int output, int primary, void *data,
 22			      char **dev_out)
 23{
 24	printk(KERN_ERR "Using a channel type which is configured out of "
 25	       "UML\n");
 26	return -ENODEV;
 27}
 28
 29static void not_configged_close(int fd, void *data)
 30{
 31	printk(KERN_ERR "Using a channel type which is configured out of "
 32	       "UML\n");
 33}
 34
 35static int not_configged_read(int fd, char *c_out, void *data)
 36{
 37	printk(KERN_ERR "Using a channel type which is configured out of "
 38	       "UML\n");
 39	return -EIO;
 40}
 41
 42static int not_configged_write(int fd, const char *buf, int len, void *data)
 43{
 44	printk(KERN_ERR "Using a channel type which is configured out of "
 45	       "UML\n");
 46	return -EIO;
 47}
 48
 49static int not_configged_console_write(int fd, const char *buf, int len)
 50{
 51	printk(KERN_ERR "Using a channel type which is configured out of "
 52	       "UML\n");
 53	return -EIO;
 54}
 55
 56static int not_configged_window_size(int fd, void *data, unsigned short *rows,
 57				     unsigned short *cols)
 58{
 59	printk(KERN_ERR "Using a channel type which is configured out of "
 60	       "UML\n");
 61	return -ENODEV;
 62}
 63
 64static void not_configged_free(void *data)
 65{
 66	printk(KERN_ERR "Using a channel type which is configured out of "
 67	       "UML\n");
 68}
 69
 70static const struct chan_ops not_configged_ops = {
 71	.init		= not_configged_init,
 72	.open		= not_configged_open,
 73	.close		= not_configged_close,
 74	.read		= not_configged_read,
 75	.write		= not_configged_write,
 76	.console_write	= not_configged_console_write,
 77	.window_size	= not_configged_window_size,
 78	.free		= not_configged_free,
 79	.winch		= 0,
 80};
 81#endif /* CONFIG_NOCONFIG_CHAN */
 82
 83static void tty_receive_char(struct tty_struct *tty, char ch)
 84{
 85	if (tty == NULL)
 86		return;
 87
 88	if (I_IXON(tty) && !I_IXOFF(tty) && !tty->raw) {
 89		if (ch == STOP_CHAR(tty)) {
 90			stop_tty(tty);
 91			return;
 92		}
 93		else if (ch == START_CHAR(tty)) {
 94			start_tty(tty);
 95			return;
 96		}
 97	}
 98
 99	tty_insert_flip_char(tty, ch, TTY_NORMAL);
100}
101
102static int open_one_chan(struct chan *chan)
103{
104	int fd, err;
105
106	if (chan->opened)
107		return 0;
108
109	if (chan->ops->open == NULL)
110		fd = 0;
111	else fd = (*chan->ops->open)(chan->input, chan->output, chan->primary,
112				     chan->data, &chan->dev);
113	if (fd < 0)
114		return fd;
115
116	err = os_set_fd_block(fd, 0);
117	if (err) {
118		(*chan->ops->close)(fd, chan->data);
119		return err;
120	}
121
122	chan->fd = fd;
123
124	chan->opened = 1;
125	return 0;
126}
127
128static int open_chan(struct list_head *chans)
129{
130	struct list_head *ele;
131	struct chan *chan;
132	int ret, err = 0;
133
134	list_for_each(ele, chans) {
135		chan = list_entry(ele, struct chan, list);
136		ret = open_one_chan(chan);
137		if (chan->primary)
138			err = ret;
139	}
140	return err;
141}
142
143void chan_enable_winch(struct list_head *chans, struct tty_struct *tty)
144{
145	struct list_head *ele;
146	struct chan *chan;
 
 
 
 
 
147
148	list_for_each(ele, chans) {
149		chan = list_entry(ele, struct chan, list);
150		if (chan->primary && chan->output && chan->ops->winch) {
151			register_winch(chan->fd, tty);
152			return;
153		}
154	}
155}
156
157int enable_chan(struct line *line)
158{
159	struct list_head *ele;
160	struct chan *chan;
161	int err;
162
 
 
163	list_for_each(ele, &line->chan_list) {
164		chan = list_entry(ele, struct chan, list);
165		err = open_one_chan(chan);
166		if (err) {
167			if (chan->primary)
168				goto out_close;
169
170			continue;
171		}
172
173		if (chan->enabled)
174			continue;
175		err = line_setup_irq(chan->fd, chan->input, chan->output, line,
176				     chan);
177		if (err)
178			goto out_close;
179
180		chan->enabled = 1;
181	}
182
183	return 0;
184
185 out_close:
186	close_chan(&line->chan_list, 0);
187	return err;
188}
189
190/* Items are added in IRQ context, when free_irq can't be called, and
191 * removed in process context, when it can.
192 * This handles interrupt sources which disappear, and which need to
193 * be permanently disabled.  This is discovered in IRQ context, but
194 * the freeing of the IRQ must be done later.
195 */
196static DEFINE_SPINLOCK(irqs_to_free_lock);
197static LIST_HEAD(irqs_to_free);
198
199void free_irqs(void)
200{
201	struct chan *chan;
202	LIST_HEAD(list);
203	struct list_head *ele;
204	unsigned long flags;
205
206	spin_lock_irqsave(&irqs_to_free_lock, flags);
207	list_splice_init(&irqs_to_free, &list);
208	spin_unlock_irqrestore(&irqs_to_free_lock, flags);
209
210	list_for_each(ele, &list) {
211		chan = list_entry(ele, struct chan, free_list);
212
213		if (chan->input && chan->enabled)
214			free_irq(chan->line->driver->read_irq, chan);
215		if (chan->output && chan->enabled)
216			free_irq(chan->line->driver->write_irq, chan);
217		chan->enabled = 0;
218	}
219}
220
221static void close_one_chan(struct chan *chan, int delay_free_irq)
222{
223	unsigned long flags;
224
225	if (!chan->opened)
226		return;
227
228	if (delay_free_irq) {
229		spin_lock_irqsave(&irqs_to_free_lock, flags);
230		list_add(&chan->free_list, &irqs_to_free);
231		spin_unlock_irqrestore(&irqs_to_free_lock, flags);
232	}
233	else {
234		if (chan->input && chan->enabled)
235			free_irq(chan->line->driver->read_irq, chan);
236		if (chan->output && chan->enabled)
237			free_irq(chan->line->driver->write_irq, chan);
238		chan->enabled = 0;
239	}
240	if (chan->ops->close != NULL)
241		(*chan->ops->close)(chan->fd, chan->data);
242
243	chan->opened = 0;
244	chan->fd = -1;
245}
246
247void close_chan(struct list_head *chans, int delay_free_irq)
248{
249	struct chan *chan;
250
251	/* Close in reverse order as open in case more than one of them
252	 * refers to the same device and they save and restore that device's
253	 * state.  Then, the first one opened will have the original state,
254	 * so it must be the last closed.
255	 */
256	list_for_each_entry_reverse(chan, chans, list) {
257		close_one_chan(chan, delay_free_irq);
258	}
259}
260
261void deactivate_chan(struct list_head *chans, int irq)
262{
263	struct list_head *ele;
264
265	struct chan *chan;
266	list_for_each(ele, chans) {
267		chan = list_entry(ele, struct chan, list);
268
269		if (chan->enabled && chan->input)
270			deactivate_fd(chan->fd, irq);
271	}
272}
273
274void reactivate_chan(struct list_head *chans, int irq)
275{
276	struct list_head *ele;
277	struct chan *chan;
278
279	list_for_each(ele, chans) {
280		chan = list_entry(ele, struct chan, list);
281
282		if (chan->enabled && chan->input)
283			reactivate_fd(chan->fd, irq);
284	}
285}
286
287int write_chan(struct list_head *chans, const char *buf, int len,
288	       int write_irq)
289{
290	struct list_head *ele;
291	struct chan *chan = NULL;
292	int n, ret = 0;
293
294	if (len == 0)
295		return 0;
296
297	list_for_each(ele, chans) {
298		chan = list_entry(ele, struct chan, list);
299		if (!chan->output || (chan->ops->write == NULL))
300			continue;
301
302		n = chan->ops->write(chan->fd, buf, len, chan->data);
303		if (chan->primary) {
304			ret = n;
305			if ((ret == -EAGAIN) || ((ret >= 0) && (ret < len)))
306				reactivate_fd(chan->fd, write_irq);
307		}
308	}
309	return ret;
310}
311
312int console_write_chan(struct list_head *chans, const char *buf, int len)
313{
314	struct list_head *ele;
315	struct chan *chan;
316	int n, ret = 0;
317
318	list_for_each(ele, chans) {
319		chan = list_entry(ele, struct chan, list);
320		if (!chan->output || (chan->ops->console_write == NULL))
321			continue;
322
323		n = chan->ops->console_write(chan->fd, buf, len);
324		if (chan->primary)
325			ret = n;
326	}
327	return ret;
328}
329
330int console_open_chan(struct line *line, struct console *co)
331{
332	int err;
333
334	err = open_chan(&line->chan_list);
335	if (err)
336		return err;
337
338	printk(KERN_INFO "Console initialized on /dev/%s%d\n", co->name,
339	       co->index);
340	return 0;
341}
342
343int chan_window_size(struct list_head *chans, unsigned short *rows_out,
344		      unsigned short *cols_out)
345{
346	struct list_head *ele;
347	struct chan *chan;
348
349	list_for_each(ele, chans) {
350		chan = list_entry(ele, struct chan, list);
351		if (chan->primary) {
352			if (chan->ops->window_size == NULL)
353				return 0;
354			return chan->ops->window_size(chan->fd, chan->data,
355						      rows_out, cols_out);
356		}
 
 
 
 
 
357	}
358	return 0;
359}
360
361static void free_one_chan(struct chan *chan, int delay_free_irq)
362{
363	list_del(&chan->list);
364
365	close_one_chan(chan, delay_free_irq);
366
367	if (chan->ops->free != NULL)
368		(*chan->ops->free)(chan->data);
369
370	if (chan->primary && chan->output)
371		ignore_sigio_fd(chan->fd);
372	kfree(chan);
373}
374
375static void free_chan(struct list_head *chans, int delay_free_irq)
376{
377	struct list_head *ele, *next;
378	struct chan *chan;
379
380	list_for_each_safe(ele, next, chans) {
381		chan = list_entry(ele, struct chan, list);
382		free_one_chan(chan, delay_free_irq);
383	}
384}
385
386static int one_chan_config_string(struct chan *chan, char *str, int size,
387				  char **error_out)
388{
389	int n = 0;
390
391	if (chan == NULL) {
392		CONFIG_CHUNK(str, size, n, "none", 1);
393		return n;
394	}
395
396	CONFIG_CHUNK(str, size, n, chan->ops->type, 0);
397
398	if (chan->dev == NULL) {
399		CONFIG_CHUNK(str, size, n, "", 1);
400		return n;
401	}
402
403	CONFIG_CHUNK(str, size, n, ":", 0);
404	CONFIG_CHUNK(str, size, n, chan->dev, 0);
405
406	return n;
407}
408
409static int chan_pair_config_string(struct chan *in, struct chan *out,
410				   char *str, int size, char **error_out)
411{
412	int n;
413
414	n = one_chan_config_string(in, str, size, error_out);
415	str += n;
416	size -= n;
417
418	if (in == out) {
419		CONFIG_CHUNK(str, size, n, "", 1);
420		return n;
421	}
422
423	CONFIG_CHUNK(str, size, n, ",", 1);
424	n = one_chan_config_string(out, str, size, error_out);
425	str += n;
426	size -= n;
427	CONFIG_CHUNK(str, size, n, "", 1);
428
429	return n;
430}
431
432int chan_config_string(struct list_head *chans, char *str, int size,
433		       char **error_out)
434{
435	struct list_head *ele;
436	struct chan *chan, *in = NULL, *out = NULL;
437
438	list_for_each(ele, chans) {
439		chan = list_entry(ele, struct chan, list);
440		if (!chan->primary)
441			continue;
442		if (chan->input)
443			in = chan;
444		if (chan->output)
445			out = chan;
446	}
447
448	return chan_pair_config_string(in, out, str, size, error_out);
449}
450
451struct chan_type {
452	char *key;
453	const struct chan_ops *ops;
454};
455
456static const struct chan_type chan_table[] = {
457	{ "fd", &fd_ops },
458
459#ifdef CONFIG_NULL_CHAN
460	{ "null", &null_ops },
461#else
462	{ "null", &not_configged_ops },
463#endif
464
465#ifdef CONFIG_PORT_CHAN
466	{ "port", &port_ops },
467#else
468	{ "port", &not_configged_ops },
469#endif
470
471#ifdef CONFIG_PTY_CHAN
472	{ "pty", &pty_ops },
473	{ "pts", &pts_ops },
474#else
475	{ "pty", &not_configged_ops },
476	{ "pts", &not_configged_ops },
477#endif
478
479#ifdef CONFIG_TTY_CHAN
480	{ "tty", &tty_ops },
481#else
482	{ "tty", &not_configged_ops },
483#endif
484
485#ifdef CONFIG_XTERM_CHAN
486	{ "xterm", &xterm_ops },
487#else
488	{ "xterm", &not_configged_ops },
489#endif
490};
491
492static struct chan *parse_chan(struct line *line, char *str, int device,
493			       const struct chan_opts *opts, char **error_out)
494{
495	const struct chan_type *entry;
496	const struct chan_ops *ops;
497	struct chan *chan;
498	void *data;
499	int i;
500
501	ops = NULL;
502	data = NULL;
503	for(i = 0; i < ARRAY_SIZE(chan_table); i++) {
504		entry = &chan_table[i];
505		if (!strncmp(str, entry->key, strlen(entry->key))) {
506			ops = entry->ops;
507			str += strlen(entry->key);
508			break;
509		}
510	}
511	if (ops == NULL) {
512		*error_out = "No match for configured backends";
513		return NULL;
514	}
515
516	data = (*ops->init)(str, device, opts);
517	if (data == NULL) {
518		*error_out = "Configuration failed";
519		return NULL;
520	}
521
522	chan = kmalloc(sizeof(*chan), GFP_ATOMIC);
523	if (chan == NULL) {
524		*error_out = "Memory allocation failed";
525		return NULL;
526	}
527	*chan = ((struct chan) { .list	 	= LIST_HEAD_INIT(chan->list),
528				 .free_list 	=
529				 	LIST_HEAD_INIT(chan->free_list),
530				 .line		= line,
531				 .primary	= 1,
532				 .input		= 0,
533				 .output 	= 0,
534				 .opened  	= 0,
535				 .enabled  	= 0,
536				 .fd 		= -1,
537				 .ops 		= ops,
538				 .data 		= data });
539	return chan;
540}
541
542int parse_chan_pair(char *str, struct line *line, int device,
543		    const struct chan_opts *opts, char **error_out)
544{
545	struct list_head *chans = &line->chan_list;
546	struct chan *new;
547	char *in, *out;
548
549	if (!list_empty(chans)) {
550		free_chan(chans, 0);
 
551		INIT_LIST_HEAD(chans);
552	}
553
 
 
 
554	out = strchr(str, ',');
555	if (out != NULL) {
556		in = str;
557		*out = '\0';
558		out++;
559		new = parse_chan(line, in, device, opts, error_out);
560		if (new == NULL)
561			return -1;
562
563		new->input = 1;
564		list_add(&new->list, chans);
 
565
566		new = parse_chan(line, out, device, opts, error_out);
567		if (new == NULL)
568			return -1;
569
570		list_add(&new->list, chans);
571		new->output = 1;
 
572	}
573	else {
574		new = parse_chan(line, str, device, opts, error_out);
575		if (new == NULL)
576			return -1;
577
578		list_add(&new->list, chans);
579		new->input = 1;
580		new->output = 1;
 
581	}
582	return 0;
583}
584
585void chan_interrupt(struct list_head *chans, struct delayed_work *task,
586		    struct tty_struct *tty, int irq)
587{
588	struct list_head *ele, *next;
589	struct chan *chan;
590	int err;
591	char c;
592
593	list_for_each_safe(ele, next, chans) {
594		chan = list_entry(ele, struct chan, list);
595		if (!chan->input || (chan->ops->read == NULL))
596			continue;
597		do {
598			if (tty && !tty_buffer_request_room(tty, 1)) {
599				schedule_delayed_work(task, 1);
600				goto out;
601			}
602			err = chan->ops->read(chan->fd, &c, chan->data);
603			if (err > 0)
604				tty_receive_char(tty, c);
605		} while (err > 0);
606
607		if (err == 0)
608			reactivate_fd(chan->fd, irq);
609		if (err == -EIO) {
610			if (chan->primary) {
611				if (tty != NULL)
612					tty_hangup(tty);
613				close_chan(chans, 1);
614				return;
615			}
616			else close_one_chan(chan, 1);
617		}
 
 
 
618	}
619 out:
620	if (tty)
621		tty_flip_buffer_push(tty);
622}