xref: /linux/drivers/pcmcia/cs.c (revision 8b1935e6a36b0967efc593d67ed3aebbfbc1f5b1)
1 /*
2  * cs.c -- Kernel Card Services - core services
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * The initial developer of the original code is David A. Hinds
9  * <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
10  * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
11  *
12  * (C) 1999		David A. Hinds
13  */
14 
15 #include <linux/module.h>
16 #include <linux/moduleparam.h>
17 #include <linux/init.h>
18 #include <linux/kernel.h>
19 #include <linux/string.h>
20 #include <linux/major.h>
21 #include <linux/errno.h>
22 #include <linux/slab.h>
23 #include <linux/mm.h>
24 #include <linux/interrupt.h>
25 #include <linux/timer.h>
26 #include <linux/ioport.h>
27 #include <linux/delay.h>
28 #include <linux/pm.h>
29 #include <linux/device.h>
30 #include <linux/kthread.h>
31 #include <linux/freezer.h>
32 #include <asm/system.h>
33 #include <asm/irq.h>
34 
35 #include <pcmcia/cs_types.h>
36 #include <pcmcia/ss.h>
37 #include <pcmcia/cs.h>
38 #include <pcmcia/cistpl.h>
39 #include <pcmcia/cisreg.h>
40 #include <pcmcia/ds.h>
41 #include "cs_internal.h"
42 
43 
44 /* Module parameters */
45 
46 MODULE_AUTHOR("David Hinds <dahinds@users.sourceforge.net>");
47 MODULE_DESCRIPTION("Linux Kernel Card Services");
48 MODULE_LICENSE("GPL");
49 
50 #define INT_MODULE_PARM(n, v) static int n = v; module_param(n, int, 0444)
51 
52 INT_MODULE_PARM(setup_delay,	10);		/* centiseconds */
53 INT_MODULE_PARM(resume_delay,	20);		/* centiseconds */
54 INT_MODULE_PARM(shutdown_delay,	3);		/* centiseconds */
55 INT_MODULE_PARM(vcc_settle,	40);		/* centiseconds */
56 INT_MODULE_PARM(reset_time,	10);		/* usecs */
57 INT_MODULE_PARM(unreset_delay,	10);		/* centiseconds */
58 INT_MODULE_PARM(unreset_check,	10);		/* centiseconds */
59 INT_MODULE_PARM(unreset_limit,	30);		/* unreset_check's */
60 
61 /* Access speed for attribute memory windows */
62 INT_MODULE_PARM(cis_speed,	300);		/* ns */
63 
64 
65 socket_state_t dead_socket = {
66 	.csc_mask	= SS_DETECT,
67 };
68 EXPORT_SYMBOL(dead_socket);
69 
70 
71 /* List of all sockets, protected by a rwsem */
72 LIST_HEAD(pcmcia_socket_list);
73 EXPORT_SYMBOL(pcmcia_socket_list);
74 
75 DECLARE_RWSEM(pcmcia_socket_list_rwsem);
76 EXPORT_SYMBOL(pcmcia_socket_list_rwsem);
77 
78 
79 /*
80  * Low-level PCMCIA socket drivers need to register with the PCCard
81  * core using pcmcia_register_socket.
82  *
83  * socket drivers are expected to use the following callbacks in their
84  * .drv struct:
85  *  - pcmcia_socket_dev_suspend
86  *  - pcmcia_socket_dev_resume
87  * These functions check for the appropriate struct pcmcia_soket arrays,
88  * and pass them to the low-level functions pcmcia_{suspend,resume}_socket
89  */
90 static int socket_early_resume(struct pcmcia_socket *skt);
91 static int socket_late_resume(struct pcmcia_socket *skt);
92 static int socket_resume(struct pcmcia_socket *skt);
93 static int socket_suspend(struct pcmcia_socket *skt);
94 
95 static void pcmcia_socket_dev_run(struct device *dev,
96 				  int (*cb)(struct pcmcia_socket *))
97 {
98 	struct pcmcia_socket *socket;
99 
100 	down_read(&pcmcia_socket_list_rwsem);
101 	list_for_each_entry(socket, &pcmcia_socket_list, socket_list) {
102 		if (socket->dev.parent != dev)
103 			continue;
104 		mutex_lock(&socket->skt_mutex);
105 		cb(socket);
106 		mutex_unlock(&socket->skt_mutex);
107 	}
108 	up_read(&pcmcia_socket_list_rwsem);
109 }
110 
111 int pcmcia_socket_dev_suspend(struct device *dev)
112 {
113 	pcmcia_socket_dev_run(dev, socket_suspend);
114 	return 0;
115 }
116 EXPORT_SYMBOL(pcmcia_socket_dev_suspend);
117 
118 void pcmcia_socket_dev_early_resume(struct device *dev)
119 {
120 	pcmcia_socket_dev_run(dev, socket_early_resume);
121 }
122 EXPORT_SYMBOL(pcmcia_socket_dev_early_resume);
123 
124 void pcmcia_socket_dev_late_resume(struct device *dev)
125 {
126 	pcmcia_socket_dev_run(dev, socket_late_resume);
127 }
128 EXPORT_SYMBOL(pcmcia_socket_dev_late_resume);
129 
130 int pcmcia_socket_dev_resume(struct device *dev)
131 {
132 	pcmcia_socket_dev_run(dev, socket_resume);
133 	return 0;
134 }
135 EXPORT_SYMBOL(pcmcia_socket_dev_resume);
136 
137 
138 struct pcmcia_socket *pcmcia_get_socket(struct pcmcia_socket *skt)
139 {
140 	struct device *dev = get_device(&skt->dev);
141 	if (!dev)
142 		return NULL;
143 	return dev_get_drvdata(dev);
144 }
145 EXPORT_SYMBOL(pcmcia_get_socket);
146 
147 
148 void pcmcia_put_socket(struct pcmcia_socket *skt)
149 {
150 	put_device(&skt->dev);
151 }
152 EXPORT_SYMBOL(pcmcia_put_socket);
153 
154 
155 static void pcmcia_release_socket(struct device *dev)
156 {
157 	struct pcmcia_socket *socket = dev_get_drvdata(dev);
158 
159 	complete(&socket->socket_released);
160 }
161 
162 static int pccardd(void *__skt);
163 
164 /**
165  * pcmcia_register_socket - add a new pcmcia socket device
166  * @socket: the &socket to register
167  */
168 int pcmcia_register_socket(struct pcmcia_socket *socket)
169 {
170 	struct task_struct *tsk;
171 	int ret;
172 
173 	if (!socket || !socket->ops || !socket->dev.parent || !socket->resource_ops)
174 		return -EINVAL;
175 
176 	dev_dbg(&socket->dev, "pcmcia_register_socket(0x%p)\n", socket->ops);
177 
178 	/* try to obtain a socket number [yes, it gets ugly if we
179 	 * register more than 2^sizeof(unsigned int) pcmcia
180 	 * sockets... but the socket number is deprecated
181 	 * anyways, so I don't care] */
182 	down_write(&pcmcia_socket_list_rwsem);
183 	if (list_empty(&pcmcia_socket_list))
184 		socket->sock = 0;
185 	else {
186 		unsigned int found, i = 1;
187 		struct pcmcia_socket *tmp;
188 		do {
189 			found = 1;
190 			list_for_each_entry(tmp, &pcmcia_socket_list, socket_list) {
191 				if (tmp->sock == i)
192 					found = 0;
193 			}
194 			i++;
195 		} while (!found);
196 		socket->sock = i - 1;
197 	}
198 	list_add_tail(&socket->socket_list, &pcmcia_socket_list);
199 	up_write(&pcmcia_socket_list_rwsem);
200 
201 #ifndef CONFIG_CARDBUS
202 	/*
203 	 * If we do not support Cardbus, ensure that
204 	 * the Cardbus socket capability is disabled.
205 	 */
206 	socket->features &= ~SS_CAP_CARDBUS;
207 #endif
208 
209 	/* set proper values in socket->dev */
210 	dev_set_drvdata(&socket->dev, socket);
211 	socket->dev.class = &pcmcia_socket_class;
212 	dev_set_name(&socket->dev, "pcmcia_socket%u", socket->sock);
213 
214 	/* base address = 0, map = 0 */
215 	socket->cis_mem.flags = 0;
216 	socket->cis_mem.speed = cis_speed;
217 
218 	INIT_LIST_HEAD(&socket->cis_cache);
219 
220 	init_completion(&socket->socket_released);
221 	init_completion(&socket->thread_done);
222 	mutex_init(&socket->skt_mutex);
223 	mutex_init(&socket->ops_mutex);
224 	spin_lock_init(&socket->thread_lock);
225 
226 	if (socket->resource_ops->init) {
227 		mutex_lock(&socket->ops_mutex);
228 		ret = socket->resource_ops->init(socket);
229 		mutex_unlock(&socket->ops_mutex);
230 		if (ret)
231 			goto err;
232 	}
233 
234 	tsk = kthread_run(pccardd, socket, "pccardd");
235 	if (IS_ERR(tsk)) {
236 		ret = PTR_ERR(tsk);
237 		goto err;
238 	}
239 
240 	wait_for_completion(&socket->thread_done);
241 	if (!socket->thread) {
242 		dev_printk(KERN_WARNING, &socket->dev,
243 			   "PCMCIA: warning: socket thread did not start\n");
244 		return -EIO;
245 	}
246 
247 	pcmcia_parse_events(socket, SS_DETECT);
248 
249 	/*
250 	 * Let's try to get the PCMCIA module for 16-bit PCMCIA support.
251 	 * If it fails, it doesn't matter -- we still have 32-bit CardBus
252 	 * support to offer, so this is not a failure mode.
253 	 */
254 	request_module_nowait("pcmcia");
255 
256 	return 0;
257 
258  err:
259 	down_write(&pcmcia_socket_list_rwsem);
260 	list_del(&socket->socket_list);
261 	up_write(&pcmcia_socket_list_rwsem);
262 	return ret;
263 } /* pcmcia_register_socket */
264 EXPORT_SYMBOL(pcmcia_register_socket);
265 
266 
267 /**
268  * pcmcia_unregister_socket - remove a pcmcia socket device
269  * @socket: the &socket to unregister
270  */
271 void pcmcia_unregister_socket(struct pcmcia_socket *socket)
272 {
273 	if (!socket)
274 		return;
275 
276 	dev_dbg(&socket->dev, "pcmcia_unregister_socket(0x%p)\n", socket->ops);
277 
278 	if (socket->thread)
279 		kthread_stop(socket->thread);
280 
281 	/* remove from our own list */
282 	down_write(&pcmcia_socket_list_rwsem);
283 	list_del(&socket->socket_list);
284 	up_write(&pcmcia_socket_list_rwsem);
285 
286 	/* wait for sysfs to drop all references */
287 	if (socket->resource_ops->exit) {
288 		mutex_lock(&socket->ops_mutex);
289 		socket->resource_ops->exit(socket);
290 		mutex_unlock(&socket->ops_mutex);
291 	}
292 	wait_for_completion(&socket->socket_released);
293 } /* pcmcia_unregister_socket */
294 EXPORT_SYMBOL(pcmcia_unregister_socket);
295 
296 
297 struct pcmcia_socket *pcmcia_get_socket_by_nr(unsigned int nr)
298 {
299 	struct pcmcia_socket *s;
300 
301 	down_read(&pcmcia_socket_list_rwsem);
302 	list_for_each_entry(s, &pcmcia_socket_list, socket_list)
303 		if (s->sock == nr) {
304 			up_read(&pcmcia_socket_list_rwsem);
305 			return s;
306 		}
307 	up_read(&pcmcia_socket_list_rwsem);
308 
309 	return NULL;
310 
311 }
312 EXPORT_SYMBOL(pcmcia_get_socket_by_nr);
313 
314 /*
315  * The central event handler.  Send_event() sends an event to the
316  * 16-bit subsystem, which then calls the relevant device drivers.
317  * Parse_events() interprets the event bits from
318  * a card status change report.  Do_shutdown() handles the high
319  * priority stuff associated with a card removal.
320  */
321 
322 /* NOTE: send_event needs to be called with skt->sem held. */
323 
324 static int send_event(struct pcmcia_socket *s, event_t event, int priority)
325 {
326 	int ret;
327 
328 	if ((s->state & SOCKET_CARDBUS) && (event != CS_EVENT_CARD_REMOVAL))
329 		return 0;
330 
331 	dev_dbg(&s->dev, "send_event(event %d, pri %d, callback 0x%p)\n",
332 	   event, priority, s->callback);
333 
334 	if (!s->callback)
335 		return 0;
336 	if (!try_module_get(s->callback->owner))
337 		return 0;
338 
339 	ret = s->callback->event(s, event, priority);
340 
341 	module_put(s->callback->owner);
342 
343 	return ret;
344 }
345 
346 static int socket_reset(struct pcmcia_socket *skt)
347 {
348 	int status, i;
349 
350 	dev_dbg(&skt->dev, "reset\n");
351 
352 	skt->socket.flags |= SS_OUTPUT_ENA | SS_RESET;
353 	skt->ops->set_socket(skt, &skt->socket);
354 	udelay((long)reset_time);
355 
356 	skt->socket.flags &= ~SS_RESET;
357 	skt->ops->set_socket(skt, &skt->socket);
358 
359 	msleep(unreset_delay * 10);
360 	for (i = 0; i < unreset_limit; i++) {
361 		skt->ops->get_status(skt, &status);
362 
363 		if (!(status & SS_DETECT))
364 			return -ENODEV;
365 
366 		if (status & SS_READY)
367 			return 0;
368 
369 		msleep(unreset_check * 10);
370 	}
371 
372 	dev_printk(KERN_ERR, &skt->dev, "time out after reset.\n");
373 	return -ETIMEDOUT;
374 }
375 
376 /*
377  * socket_setup() and socket_shutdown() are called by the main event handler
378  * when card insertion and removal events are received.
379  * socket_setup() turns on socket power and resets the socket, in two stages.
380  * socket_shutdown() unconfigures a socket and turns off socket power.
381  */
382 static void socket_shutdown(struct pcmcia_socket *s)
383 {
384 	int status;
385 
386 	dev_dbg(&s->dev, "shutdown\n");
387 
388 	send_event(s, CS_EVENT_CARD_REMOVAL, CS_EVENT_PRI_HIGH);
389 
390 	mutex_lock(&s->ops_mutex);
391 	s->state &= SOCKET_INUSE | SOCKET_PRESENT;
392 	msleep(shutdown_delay * 10);
393 	s->state &= SOCKET_INUSE;
394 
395 	/* Blank out the socket state */
396 	s->socket = dead_socket;
397 	s->ops->init(s);
398 	s->ops->set_socket(s, &s->socket);
399 	s->irq.AssignedIRQ = s->irq.Config = 0;
400 	s->lock_count = 0;
401 	kfree(s->fake_cis);
402 	s->fake_cis = NULL;
403 	s->functions = 0;
404 
405 	/* From here on we can be sure that only we (that is, the
406 	 * pccardd thread) accesses this socket, and all (16-bit)
407 	 * PCMCIA interactions are gone. Therefore, release
408 	 * ops_mutex so that we don't get a sysfs-related lockdep
409 	 * warning.
410 	 */
411 	mutex_unlock(&s->ops_mutex);
412 
413 #ifdef CONFIG_CARDBUS
414 	cb_free(s);
415 #endif
416 
417 	/* give socket some time to power down */
418 	msleep(100);
419 
420 	s->ops->get_status(s, &status);
421 	if (status & SS_POWERON) {
422 		dev_printk(KERN_ERR, &s->dev,
423 			   "*** DANGER *** unable to remove socket power\n");
424 	}
425 
426 	s->state &= ~SOCKET_INUSE;
427 }
428 
429 static int socket_setup(struct pcmcia_socket *skt, int initial_delay)
430 {
431 	int status, i;
432 
433 	dev_dbg(&skt->dev, "setup\n");
434 
435 	skt->ops->get_status(skt, &status);
436 	if (!(status & SS_DETECT))
437 		return -ENODEV;
438 
439 	msleep(initial_delay * 10);
440 
441 	for (i = 0; i < 100; i++) {
442 		skt->ops->get_status(skt, &status);
443 		if (!(status & SS_DETECT))
444 			return -ENODEV;
445 
446 		if (!(status & SS_PENDING))
447 			break;
448 
449 		msleep(100);
450 	}
451 
452 	if (status & SS_PENDING) {
453 		dev_printk(KERN_ERR, &skt->dev,
454 			   "voltage interrogation timed out.\n");
455 		return -ETIMEDOUT;
456 	}
457 
458 	if (status & SS_CARDBUS) {
459 		if (!(skt->features & SS_CAP_CARDBUS)) {
460 			dev_printk(KERN_ERR, &skt->dev,
461 				"cardbus cards are not supported.\n");
462 			return -EINVAL;
463 		}
464 		skt->state |= SOCKET_CARDBUS;
465 	} else
466 		skt->state &= ~SOCKET_CARDBUS;
467 
468 	/*
469 	 * Decode the card voltage requirements, and apply power to the card.
470 	 */
471 	if (status & SS_3VCARD)
472 		skt->socket.Vcc = skt->socket.Vpp = 33;
473 	else if (!(status & SS_XVCARD))
474 		skt->socket.Vcc = skt->socket.Vpp = 50;
475 	else {
476 		dev_printk(KERN_ERR, &skt->dev, "unsupported voltage key.\n");
477 		return -EIO;
478 	}
479 
480 	if (skt->power_hook)
481 		skt->power_hook(skt, HOOK_POWER_PRE);
482 
483 	skt->socket.flags = 0;
484 	skt->ops->set_socket(skt, &skt->socket);
485 
486 	/*
487 	 * Wait "vcc_settle" for the supply to stabilise.
488 	 */
489 	msleep(vcc_settle * 10);
490 
491 	skt->ops->get_status(skt, &status);
492 	if (!(status & SS_POWERON)) {
493 		dev_printk(KERN_ERR, &skt->dev, "unable to apply power.\n");
494 		return -EIO;
495 	}
496 
497 	status = socket_reset(skt);
498 
499 	if (skt->power_hook)
500 		skt->power_hook(skt, HOOK_POWER_POST);
501 
502 	return status;
503 }
504 
505 /*
506  * Handle card insertion.  Setup the socket, reset the card,
507  * and then tell the rest of PCMCIA that a card is present.
508  */
509 static int socket_insert(struct pcmcia_socket *skt)
510 {
511 	int ret;
512 
513 	dev_dbg(&skt->dev, "insert\n");
514 
515 	mutex_lock(&skt->ops_mutex);
516 	if (skt->state & SOCKET_INUSE) {
517 		mutex_unlock(&skt->ops_mutex);
518 		return -EINVAL;
519 	}
520 	skt->state |= SOCKET_INUSE;
521 
522 	ret = socket_setup(skt, setup_delay);
523 	if (ret == 0) {
524 		skt->state |= SOCKET_PRESENT;
525 
526 		dev_printk(KERN_NOTICE, &skt->dev,
527 			   "pccard: %s card inserted into slot %d\n",
528 			   (skt->state & SOCKET_CARDBUS) ? "CardBus" : "PCMCIA",
529 			   skt->sock);
530 
531 #ifdef CONFIG_CARDBUS
532 		if (skt->state & SOCKET_CARDBUS) {
533 			cb_alloc(skt);
534 			skt->state |= SOCKET_CARDBUS_CONFIG;
535 		}
536 #endif
537 		dev_dbg(&skt->dev, "insert done\n");
538 		mutex_unlock(&skt->ops_mutex);
539 
540 		send_event(skt, CS_EVENT_CARD_INSERTION, CS_EVENT_PRI_LOW);
541 	} else {
542 		mutex_unlock(&skt->ops_mutex);
543 		socket_shutdown(skt);
544 	}
545 
546 	return ret;
547 }
548 
549 static int socket_suspend(struct pcmcia_socket *skt)
550 {
551 	if (skt->state & SOCKET_SUSPEND)
552 		return -EBUSY;
553 
554 	mutex_lock(&skt->ops_mutex);
555 	skt->suspended_state = skt->state;
556 
557 	send_event(skt, CS_EVENT_PM_SUSPEND, CS_EVENT_PRI_LOW);
558 	skt->socket = dead_socket;
559 	skt->ops->set_socket(skt, &skt->socket);
560 	if (skt->ops->suspend)
561 		skt->ops->suspend(skt);
562 	skt->state |= SOCKET_SUSPEND;
563 	mutex_unlock(&skt->ops_mutex);
564 	return 0;
565 }
566 
567 static int socket_early_resume(struct pcmcia_socket *skt)
568 {
569 	mutex_lock(&skt->ops_mutex);
570 	skt->socket = dead_socket;
571 	skt->ops->init(skt);
572 	skt->ops->set_socket(skt, &skt->socket);
573 	if (skt->state & SOCKET_PRESENT)
574 		skt->resume_status = socket_setup(skt, resume_delay);
575 	mutex_unlock(&skt->ops_mutex);
576 	return 0;
577 }
578 
579 static int socket_late_resume(struct pcmcia_socket *skt)
580 {
581 	mutex_lock(&skt->ops_mutex);
582 	skt->state &= ~SOCKET_SUSPEND;
583 	mutex_unlock(&skt->ops_mutex);
584 
585 	if (!(skt->state & SOCKET_PRESENT))
586 		return socket_insert(skt);
587 
588 	if (skt->resume_status) {
589 		socket_shutdown(skt);
590 		return 0;
591 	}
592 
593 	if (skt->suspended_state != skt->state) {
594 		dev_dbg(&skt->dev,
595 			"suspend state 0x%x != resume state 0x%x\n",
596 			skt->suspended_state, skt->state);
597 
598 		socket_shutdown(skt);
599 		return socket_insert(skt);
600 	}
601 
602 #ifdef CONFIG_CARDBUS
603 	if (skt->state & SOCKET_CARDBUS) {
604 		/* We can't be sure the CardBus card is the same
605 		 * as the one previously inserted. Therefore, remove
606 		 * and re-add... */
607 		cb_free(skt);
608 		cb_alloc(skt);
609 		return 0;
610 	}
611 #endif
612 
613 	send_event(skt, CS_EVENT_PM_RESUME, CS_EVENT_PRI_LOW);
614 	return 0;
615 }
616 
617 /*
618  * Resume a socket.  If a card is present, verify its CIS against
619  * our cached copy.  If they are different, the card has been
620  * replaced, and we need to tell the drivers.
621  */
622 static int socket_resume(struct pcmcia_socket *skt)
623 {
624 	if (!(skt->state & SOCKET_SUSPEND))
625 		return -EBUSY;
626 
627 	socket_early_resume(skt);
628 	return socket_late_resume(skt);
629 }
630 
631 static void socket_remove(struct pcmcia_socket *skt)
632 {
633 	dev_printk(KERN_NOTICE, &skt->dev,
634 		   "pccard: card ejected from slot %d\n", skt->sock);
635 	socket_shutdown(skt);
636 }
637 
638 /*
639  * Process a socket card detect status change.
640  *
641  * If we don't have a card already present, delay the detect event for
642  * about 20ms (to be on the safe side) before reading the socket status.
643  *
644  * Some i82365-based systems send multiple SS_DETECT events during card
645  * insertion, and the "card present" status bit seems to bounce.  This
646  * will probably be true with GPIO-based card detection systems after
647  * the product has aged.
648  */
649 static void socket_detect_change(struct pcmcia_socket *skt)
650 {
651 	if (!(skt->state & SOCKET_SUSPEND)) {
652 		int status;
653 
654 		if (!(skt->state & SOCKET_PRESENT))
655 			msleep(20);
656 
657 		skt->ops->get_status(skt, &status);
658 		if ((skt->state & SOCKET_PRESENT) &&
659 		     !(status & SS_DETECT))
660 			socket_remove(skt);
661 		if (!(skt->state & SOCKET_PRESENT) &&
662 		    (status & SS_DETECT))
663 			socket_insert(skt);
664 	}
665 }
666 
667 static int pccardd(void *__skt)
668 {
669 	struct pcmcia_socket *skt = __skt;
670 	int ret;
671 
672 	skt->thread = current;
673 	skt->socket = dead_socket;
674 	skt->ops->init(skt);
675 	skt->ops->set_socket(skt, &skt->socket);
676 
677 	/* register with the device core */
678 	ret = device_register(&skt->dev);
679 	if (ret) {
680 		dev_printk(KERN_WARNING, &skt->dev,
681 			   "PCMCIA: unable to register socket\n");
682 		skt->thread = NULL;
683 		complete(&skt->thread_done);
684 		return 0;
685 	}
686 	ret = pccard_sysfs_add_socket(&skt->dev);
687 	if (ret)
688 		dev_warn(&skt->dev, "err %d adding socket attributes\n", ret);
689 
690 	complete(&skt->thread_done);
691 
692 	/* wait for userspace to catch up */
693 	msleep(250);
694 
695 	set_freezable();
696 	for (;;) {
697 		unsigned long flags;
698 		unsigned int events;
699 		unsigned int sysfs_events;
700 
701 		set_current_state(TASK_INTERRUPTIBLE);
702 
703 		spin_lock_irqsave(&skt->thread_lock, flags);
704 		events = skt->thread_events;
705 		skt->thread_events = 0;
706 		sysfs_events = skt->sysfs_events;
707 		skt->sysfs_events = 0;
708 		spin_unlock_irqrestore(&skt->thread_lock, flags);
709 
710 		mutex_lock(&skt->skt_mutex);
711 		if (events) {
712 			if (events & SS_DETECT)
713 				socket_detect_change(skt);
714 			if (events & SS_BATDEAD)
715 				send_event(skt, CS_EVENT_BATTERY_DEAD, CS_EVENT_PRI_LOW);
716 			if (events & SS_BATWARN)
717 				send_event(skt, CS_EVENT_BATTERY_LOW, CS_EVENT_PRI_LOW);
718 			if (events & SS_READY)
719 				send_event(skt, CS_EVENT_READY_CHANGE, CS_EVENT_PRI_LOW);
720 		}
721 
722 		if (sysfs_events) {
723 			if (sysfs_events & PCMCIA_UEVENT_EJECT)
724 				socket_remove(skt);
725 			if (sysfs_events & PCMCIA_UEVENT_INSERT)
726 				socket_insert(skt);
727 			if ((sysfs_events & PCMCIA_UEVENT_RESUME) &&
728 				!(skt->state & SOCKET_CARDBUS)) {
729 				ret = socket_resume(skt);
730 				if (!ret && skt->callback)
731 					skt->callback->resume(skt);
732 			}
733 			if ((sysfs_events & PCMCIA_UEVENT_SUSPEND) &&
734 				!(skt->state & SOCKET_CARDBUS)) {
735 				if (skt->callback)
736 					ret = skt->callback->suspend(skt);
737 				else
738 					ret = 0;
739 				if (!ret)
740 					socket_suspend(skt);
741 			}
742 			if ((sysfs_events & PCMCIA_UEVENT_REQUERY) &&
743 				!(skt->state & SOCKET_CARDBUS)) {
744 				if (!ret && skt->callback)
745 					skt->callback->requery(skt);
746 			}
747 		}
748 		mutex_unlock(&skt->skt_mutex);
749 
750 		if (events || sysfs_events)
751 			continue;
752 
753 		if (kthread_should_stop())
754 			break;
755 
756 		schedule();
757 		try_to_freeze();
758 	}
759 	/* make sure we are running before we exit */
760 	set_current_state(TASK_RUNNING);
761 
762 	/* shut down socket, if a device is still present */
763 	if (skt->state & SOCKET_PRESENT) {
764 		mutex_lock(&skt->skt_mutex);
765 		socket_remove(skt);
766 		mutex_unlock(&skt->skt_mutex);
767 	}
768 
769 	/* remove from the device core */
770 	pccard_sysfs_remove_socket(&skt->dev);
771 	device_unregister(&skt->dev);
772 
773 	return 0;
774 }
775 
776 /*
777  * Yenta (at least) probes interrupts before registering the socket and
778  * starting the handler thread.
779  */
780 void pcmcia_parse_events(struct pcmcia_socket *s, u_int events)
781 {
782 	unsigned long flags;
783 	dev_dbg(&s->dev, "parse_events: events %08x\n", events);
784 	if (s->thread) {
785 		spin_lock_irqsave(&s->thread_lock, flags);
786 		s->thread_events |= events;
787 		spin_unlock_irqrestore(&s->thread_lock, flags);
788 
789 		wake_up_process(s->thread);
790 	}
791 } /* pcmcia_parse_events */
792 EXPORT_SYMBOL(pcmcia_parse_events);
793 
794 /**
795  * pcmcia_parse_uevents() - tell pccardd to issue manual commands
796  * @s:		the PCMCIA socket we wan't to command
797  * @events:	events to pass to pccardd
798  *
799  * userspace-issued insert, eject, suspend and resume commands must be
800  * handled by pccardd to avoid any sysfs-related deadlocks. Valid events
801  * are PCMCIA_UEVENT_EJECT (for eject), PCMCIA_UEVENT__INSERT (for insert),
802  * PCMCIA_UEVENT_RESUME (for resume), PCMCIA_UEVENT_SUSPEND (for suspend)
803  * and PCMCIA_UEVENT_REQUERY (for re-querying the PCMCIA card).
804  */
805 void pcmcia_parse_uevents(struct pcmcia_socket *s, u_int events)
806 {
807 	unsigned long flags;
808 	dev_dbg(&s->dev, "parse_uevents: events %08x\n", events);
809 	if (s->thread) {
810 		spin_lock_irqsave(&s->thread_lock, flags);
811 		s->sysfs_events |= events;
812 		spin_unlock_irqrestore(&s->thread_lock, flags);
813 
814 		wake_up_process(s->thread);
815 	}
816 }
817 EXPORT_SYMBOL(pcmcia_parse_uevents);
818 
819 
820 /* register pcmcia_callback */
821 int pccard_register_pcmcia(struct pcmcia_socket *s, struct pcmcia_callback *c)
822 {
823 	int ret = 0;
824 
825 	/* s->skt_mutex also protects s->callback */
826 	mutex_lock(&s->skt_mutex);
827 
828 	if (c) {
829 		/* registration */
830 		if (s->callback) {
831 			ret = -EBUSY;
832 			goto err;
833 		}
834 
835 		s->callback = c;
836 
837 		if ((s->state & (SOCKET_PRESENT|SOCKET_CARDBUS)) == SOCKET_PRESENT)
838 			send_event(s, CS_EVENT_CARD_INSERTION, CS_EVENT_PRI_LOW);
839 	} else
840 		s->callback = NULL;
841  err:
842 	mutex_unlock(&s->skt_mutex);
843 
844 	return ret;
845 }
846 EXPORT_SYMBOL(pccard_register_pcmcia);
847 
848 
849 /* I'm not sure which "reset" function this is supposed to use,
850  * but for now, it uses the low-level interface's reset, not the
851  * CIS register.
852  */
853 
854 int pcmcia_reset_card(struct pcmcia_socket *skt)
855 {
856 	int ret;
857 
858 	dev_dbg(&skt->dev, "resetting socket\n");
859 
860 	mutex_lock(&skt->skt_mutex);
861 	do {
862 		if (!(skt->state & SOCKET_PRESENT)) {
863 			dev_dbg(&skt->dev, "can't reset, not present\n");
864 			ret = -ENODEV;
865 			break;
866 		}
867 		if (skt->state & SOCKET_SUSPEND) {
868 			dev_dbg(&skt->dev, "can't reset, suspended\n");
869 			ret = -EBUSY;
870 			break;
871 		}
872 		if (skt->state & SOCKET_CARDBUS) {
873 			dev_dbg(&skt->dev, "can't reset, is cardbus\n");
874 			ret = -EPERM;
875 			break;
876 		}
877 
878 		ret = send_event(skt, CS_EVENT_RESET_REQUEST, CS_EVENT_PRI_LOW);
879 		if (ret == 0) {
880 			send_event(skt, CS_EVENT_RESET_PHYSICAL, CS_EVENT_PRI_LOW);
881 			if (skt->callback)
882 				skt->callback->suspend(skt);
883 			mutex_lock(&skt->ops_mutex);
884 			ret = socket_reset(skt);
885 			mutex_unlock(&skt->ops_mutex);
886 			if (ret == 0) {
887 				send_event(skt, CS_EVENT_CARD_RESET, CS_EVENT_PRI_LOW);
888 				if (skt->callback)
889 					skt->callback->resume(skt);
890 			}
891 		}
892 
893 		ret = 0;
894 	} while (0);
895 	mutex_unlock(&skt->skt_mutex);
896 
897 	return ret;
898 } /* reset_card */
899 EXPORT_SYMBOL(pcmcia_reset_card);
900 
901 
902 static int pcmcia_socket_uevent(struct device *dev,
903 				struct kobj_uevent_env *env)
904 {
905 	struct pcmcia_socket *s = container_of(dev, struct pcmcia_socket, dev);
906 
907 	if (add_uevent_var(env, "SOCKET_NO=%u", s->sock))
908 		return -ENOMEM;
909 
910 	return 0;
911 }
912 
913 
914 static struct completion pcmcia_unload;
915 
916 static void pcmcia_release_socket_class(struct class *data)
917 {
918 	complete(&pcmcia_unload);
919 }
920 
921 
922 struct class pcmcia_socket_class = {
923 	.name = "pcmcia_socket",
924 	.dev_uevent = pcmcia_socket_uevent,
925 	.dev_release = pcmcia_release_socket,
926 	.class_release = pcmcia_release_socket_class,
927 };
928 EXPORT_SYMBOL(pcmcia_socket_class);
929 
930 
931 static int __init init_pcmcia_cs(void)
932 {
933 	init_completion(&pcmcia_unload);
934 	return class_register(&pcmcia_socket_class);
935 }
936 
937 static void __exit exit_pcmcia_cs(void)
938 {
939 	class_unregister(&pcmcia_socket_class);
940 	wait_for_completion(&pcmcia_unload);
941 }
942 
943 subsys_initcall(init_pcmcia_cs);
944 module_exit(exit_pcmcia_cs);
945 
946