xref: /openbmc/linux/drivers/memstick/core/memstick.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /*
2  *  Sony MemoryStick support
3  *
4  *  Copyright (C) 2007 Alex Dubov <oakad@yahoo.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * Special thanks to Carlos Corbacho for providing various MemoryStick cards
11  * that made this driver possible.
12  *
13  */
14 
15 #include <linux/memstick.h>
16 #include <linux/idr.h>
17 #include <linux/fs.h>
18 #include <linux/delay.h>
19 #include <linux/slab.h>
20 
21 #define DRIVER_NAME "memstick"
22 
23 static unsigned int cmd_retries = 3;
24 module_param(cmd_retries, uint, 0644);
25 
26 static struct workqueue_struct *workqueue;
27 static DEFINE_IDR(memstick_host_idr);
28 static DEFINE_SPINLOCK(memstick_host_lock);
29 
30 static int memstick_dev_match(struct memstick_dev *card,
31 			      struct memstick_device_id *id)
32 {
33 	if (id->match_flags & MEMSTICK_MATCH_ALL) {
34 		if ((id->type == card->id.type)
35 		    && (id->category == card->id.category)
36 		    && (id->class == card->id.class))
37 			return 1;
38 	}
39 
40 	return 0;
41 }
42 
43 static int memstick_bus_match(struct device *dev, struct device_driver *drv)
44 {
45 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
46 						 dev);
47 	struct memstick_driver *ms_drv = container_of(drv,
48 						      struct memstick_driver,
49 						      driver);
50 	struct memstick_device_id *ids = ms_drv->id_table;
51 
52 	if (ids) {
53 		while (ids->match_flags) {
54 			if (memstick_dev_match(card, ids))
55 				return 1;
56 			++ids;
57 		}
58 	}
59 	return 0;
60 }
61 
62 static int memstick_uevent(struct device *dev, struct kobj_uevent_env *env)
63 {
64 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
65 						  dev);
66 
67 	if (add_uevent_var(env, "MEMSTICK_TYPE=%02X", card->id.type))
68 		return -ENOMEM;
69 
70 	if (add_uevent_var(env, "MEMSTICK_CATEGORY=%02X", card->id.category))
71 		return -ENOMEM;
72 
73 	if (add_uevent_var(env, "MEMSTICK_CLASS=%02X", card->id.class))
74 		return -ENOMEM;
75 
76 	return 0;
77 }
78 
79 static int memstick_device_probe(struct device *dev)
80 {
81 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
82 						 dev);
83 	struct memstick_driver *drv = container_of(dev->driver,
84 						   struct memstick_driver,
85 						   driver);
86 	int rc = -ENODEV;
87 
88 	if (dev->driver && drv->probe) {
89 		rc = drv->probe(card);
90 		if (!rc)
91 			get_device(dev);
92 	}
93 	return rc;
94 }
95 
96 static int memstick_device_remove(struct device *dev)
97 {
98 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
99 						  dev);
100 	struct memstick_driver *drv = container_of(dev->driver,
101 						   struct memstick_driver,
102 						   driver);
103 
104 	if (dev->driver && drv->remove) {
105 		drv->remove(card);
106 		card->dev.driver = NULL;
107 	}
108 
109 	put_device(dev);
110 	return 0;
111 }
112 
113 #ifdef CONFIG_PM
114 
115 static int memstick_device_suspend(struct device *dev, pm_message_t state)
116 {
117 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
118 						  dev);
119 	struct memstick_driver *drv = container_of(dev->driver,
120 						   struct memstick_driver,
121 						   driver);
122 
123 	if (dev->driver && drv->suspend)
124 		return drv->suspend(card, state);
125 	return 0;
126 }
127 
128 static int memstick_device_resume(struct device *dev)
129 {
130 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
131 						  dev);
132 	struct memstick_driver *drv = container_of(dev->driver,
133 						   struct memstick_driver,
134 						   driver);
135 
136 	if (dev->driver && drv->resume)
137 		return drv->resume(card);
138 	return 0;
139 }
140 
141 #else
142 
143 #define memstick_device_suspend NULL
144 #define memstick_device_resume NULL
145 
146 #endif /* CONFIG_PM */
147 
148 #define MEMSTICK_ATTR(name, format)                                           \
149 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, \
150 			    char *buf)                                        \
151 {                                                                             \
152 	struct memstick_dev *card = container_of(dev, struct memstick_dev,    \
153 						 dev);                        \
154 	return sprintf(buf, format, card->id.name);                           \
155 }
156 
157 MEMSTICK_ATTR(type, "%02X");
158 MEMSTICK_ATTR(category, "%02X");
159 MEMSTICK_ATTR(class, "%02X");
160 
161 #define MEMSTICK_ATTR_RO(name) __ATTR(name, S_IRUGO, name##_show, NULL)
162 
163 static struct device_attribute memstick_dev_attrs[] = {
164 	MEMSTICK_ATTR_RO(type),
165 	MEMSTICK_ATTR_RO(category),
166 	MEMSTICK_ATTR_RO(class),
167 	__ATTR_NULL
168 };
169 
170 static struct bus_type memstick_bus_type = {
171 	.name           = "memstick",
172 	.dev_attrs      = memstick_dev_attrs,
173 	.match          = memstick_bus_match,
174 	.uevent         = memstick_uevent,
175 	.probe          = memstick_device_probe,
176 	.remove         = memstick_device_remove,
177 	.suspend        = memstick_device_suspend,
178 	.resume         = memstick_device_resume
179 };
180 
181 static void memstick_free(struct device *dev)
182 {
183 	struct memstick_host *host = container_of(dev, struct memstick_host,
184 						  dev);
185 	kfree(host);
186 }
187 
188 static struct class memstick_host_class = {
189 	.name        = "memstick_host",
190 	.dev_release = memstick_free
191 };
192 
193 static void memstick_free_card(struct device *dev)
194 {
195 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
196 						 dev);
197 	kfree(card);
198 }
199 
200 static int memstick_dummy_check(struct memstick_dev *card)
201 {
202 	return 0;
203 }
204 
205 /**
206  * memstick_detect_change - schedule media detection on memstick host
207  * @host - host to use
208  */
209 void memstick_detect_change(struct memstick_host *host)
210 {
211 	queue_work(workqueue, &host->media_checker);
212 }
213 EXPORT_SYMBOL(memstick_detect_change);
214 
215 /**
216  * memstick_next_req - called by host driver to obtain next request to process
217  * @host - host to use
218  * @mrq - pointer to stick the request to
219  *
220  * Host calls this function from idle state (*mrq == NULL) or after finishing
221  * previous request (*mrq should point to it). If previous request was
222  * unsuccessful, it is retried for predetermined number of times. Return value
223  * of 0 means that new request was assigned to the host.
224  */
225 int memstick_next_req(struct memstick_host *host, struct memstick_request **mrq)
226 {
227 	int rc = -ENXIO;
228 
229 	if ((*mrq) && (*mrq)->error && host->retries) {
230 		(*mrq)->error = rc;
231 		host->retries--;
232 		return 0;
233 	}
234 
235 	if (host->card && host->card->next_request)
236 		rc = host->card->next_request(host->card, mrq);
237 
238 	if (!rc)
239 		host->retries = cmd_retries > 1 ? cmd_retries - 1 : 1;
240 	else
241 		*mrq = NULL;
242 
243 	return rc;
244 }
245 EXPORT_SYMBOL(memstick_next_req);
246 
247 /**
248  * memstick_new_req - notify the host that some requests are pending
249  * @host - host to use
250  */
251 void memstick_new_req(struct memstick_host *host)
252 {
253 	if (host->card) {
254 		host->retries = cmd_retries;
255 		INIT_COMPLETION(host->card->mrq_complete);
256 		host->request(host);
257 	}
258 }
259 EXPORT_SYMBOL(memstick_new_req);
260 
261 /**
262  * memstick_init_req_sg - set request fields needed for bulk data transfer
263  * @mrq - request to use
264  * @tpc - memstick Transport Protocol Command
265  * @sg - TPC argument
266  */
267 void memstick_init_req_sg(struct memstick_request *mrq, unsigned char tpc,
268 			  const struct scatterlist *sg)
269 {
270 	mrq->tpc = tpc;
271 	if (tpc & 8)
272 		mrq->data_dir = WRITE;
273 	else
274 		mrq->data_dir = READ;
275 
276 	mrq->sg = *sg;
277 	mrq->long_data = 1;
278 
279 	if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
280 		mrq->need_card_int = 1;
281 	else
282 		mrq->need_card_int = 0;
283 }
284 EXPORT_SYMBOL(memstick_init_req_sg);
285 
286 /**
287  * memstick_init_req - set request fields needed for short data transfer
288  * @mrq - request to use
289  * @tpc - memstick Transport Protocol Command
290  * @buf - TPC argument buffer
291  * @length - TPC argument size
292  *
293  * The intended use of this function (transfer of data items several bytes
294  * in size) allows us to just copy the value between request structure and
295  * user supplied buffer.
296  */
297 void memstick_init_req(struct memstick_request *mrq, unsigned char tpc,
298 		       const void *buf, size_t length)
299 {
300 	mrq->tpc = tpc;
301 	if (tpc & 8)
302 		mrq->data_dir = WRITE;
303 	else
304 		mrq->data_dir = READ;
305 
306 	mrq->data_len = length > sizeof(mrq->data) ? sizeof(mrq->data) : length;
307 	if (mrq->data_dir == WRITE)
308 		memcpy(mrq->data, buf, mrq->data_len);
309 
310 	mrq->long_data = 0;
311 
312 	if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
313 		mrq->need_card_int = 1;
314 	else
315 		mrq->need_card_int = 0;
316 }
317 EXPORT_SYMBOL(memstick_init_req);
318 
319 /*
320  * Functions prefixed with "h_" are protocol callbacks. They can be called from
321  * interrupt context. Return value of 0 means that request processing is still
322  * ongoing, while special error value of -EAGAIN means that current request is
323  * finished (and request processor should come back some time later).
324  */
325 
326 static int h_memstick_read_dev_id(struct memstick_dev *card,
327 				  struct memstick_request **mrq)
328 {
329 	struct ms_id_register id_reg;
330 
331 	if (!(*mrq)) {
332 		memstick_init_req(&card->current_mrq, MS_TPC_READ_REG, NULL,
333 				  sizeof(struct ms_id_register));
334 		*mrq = &card->current_mrq;
335 		return 0;
336 	} else {
337 		if (!(*mrq)->error) {
338 			memcpy(&id_reg, (*mrq)->data, sizeof(id_reg));
339 			card->id.match_flags = MEMSTICK_MATCH_ALL;
340 			card->id.type = id_reg.type;
341 			card->id.category = id_reg.category;
342 			card->id.class = id_reg.class;
343 			dev_dbg(&card->dev, "if_mode = %02x\n", id_reg.if_mode);
344 		}
345 		complete(&card->mrq_complete);
346 		return -EAGAIN;
347 	}
348 }
349 
350 static int h_memstick_set_rw_addr(struct memstick_dev *card,
351 				  struct memstick_request **mrq)
352 {
353 	if (!(*mrq)) {
354 		memstick_init_req(&card->current_mrq, MS_TPC_SET_RW_REG_ADRS,
355 				  (char *)&card->reg_addr,
356 				  sizeof(card->reg_addr));
357 		*mrq = &card->current_mrq;
358 		return 0;
359 	} else {
360 		complete(&card->mrq_complete);
361 		return -EAGAIN;
362 	}
363 }
364 
365 /**
366  * memstick_set_rw_addr - issue SET_RW_REG_ADDR request and wait for it to
367  *                        complete
368  * @card - media device to use
369  */
370 int memstick_set_rw_addr(struct memstick_dev *card)
371 {
372 	card->next_request = h_memstick_set_rw_addr;
373 	memstick_new_req(card->host);
374 	wait_for_completion(&card->mrq_complete);
375 
376 	return card->current_mrq.error;
377 }
378 EXPORT_SYMBOL(memstick_set_rw_addr);
379 
380 static struct memstick_dev *memstick_alloc_card(struct memstick_host *host)
381 {
382 	struct memstick_dev *card = kzalloc(sizeof(struct memstick_dev),
383 					    GFP_KERNEL);
384 	struct memstick_dev *old_card = host->card;
385 	struct ms_id_register id_reg;
386 
387 	if (card) {
388 		card->host = host;
389 		dev_set_name(&card->dev, "%s", dev_name(&host->dev));
390 		card->dev.parent = &host->dev;
391 		card->dev.bus = &memstick_bus_type;
392 		card->dev.release = memstick_free_card;
393 		card->check = memstick_dummy_check;
394 
395 		card->reg_addr.r_offset = offsetof(struct ms_register, id);
396 		card->reg_addr.r_length = sizeof(id_reg);
397 		card->reg_addr.w_offset = offsetof(struct ms_register, id);
398 		card->reg_addr.w_length = sizeof(id_reg);
399 
400 		init_completion(&card->mrq_complete);
401 
402 		host->card = card;
403 		if (memstick_set_rw_addr(card))
404 			goto err_out;
405 
406 		card->next_request = h_memstick_read_dev_id;
407 		memstick_new_req(host);
408 		wait_for_completion(&card->mrq_complete);
409 
410 		if (card->current_mrq.error)
411 			goto err_out;
412 	}
413 	host->card = old_card;
414 	return card;
415 err_out:
416 	host->card = old_card;
417 	kfree(card);
418 	return NULL;
419 }
420 
421 static int memstick_power_on(struct memstick_host *host)
422 {
423 	int rc = host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_ON);
424 
425 	if (!rc)
426 		rc = host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
427 
428 	return rc;
429 }
430 
431 static void memstick_check(struct work_struct *work)
432 {
433 	struct memstick_host *host = container_of(work, struct memstick_host,
434 						  media_checker);
435 	struct memstick_dev *card;
436 
437 	dev_dbg(&host->dev, "memstick_check started\n");
438 	mutex_lock(&host->lock);
439 	if (!host->card) {
440 		if (memstick_power_on(host))
441 			goto out_power_off;
442 	} else if (host->card->stop)
443 		host->card->stop(host->card);
444 
445 	card = memstick_alloc_card(host);
446 
447 	if (!card) {
448 		if (host->card) {
449 			device_unregister(&host->card->dev);
450 			host->card = NULL;
451 		}
452 	} else {
453 		dev_dbg(&host->dev, "new card %02x, %02x, %02x\n",
454 			card->id.type, card->id.category, card->id.class);
455 		if (host->card) {
456 			if (memstick_set_rw_addr(host->card)
457 			    || !memstick_dev_match(host->card, &card->id)
458 			    || !(host->card->check(host->card))) {
459 				device_unregister(&host->card->dev);
460 				host->card = NULL;
461 			} else if (host->card->start)
462 				host->card->start(host->card);
463 		}
464 
465 		if (!host->card) {
466 			host->card = card;
467 			if (device_register(&card->dev)) {
468 				put_device(&card->dev);
469 				kfree(host->card);
470 				host->card = NULL;
471 			}
472 		} else
473 			kfree(card);
474 	}
475 
476 out_power_off:
477 	if (!host->card)
478 		host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
479 
480 	mutex_unlock(&host->lock);
481 	dev_dbg(&host->dev, "memstick_check finished\n");
482 }
483 
484 /**
485  * memstick_alloc_host - allocate a memstick_host structure
486  * @extra: size of the user private data to allocate
487  * @dev: parent device of the host
488  */
489 struct memstick_host *memstick_alloc_host(unsigned int extra,
490 					  struct device *dev)
491 {
492 	struct memstick_host *host;
493 
494 	host = kzalloc(sizeof(struct memstick_host) + extra, GFP_KERNEL);
495 	if (host) {
496 		mutex_init(&host->lock);
497 		INIT_WORK(&host->media_checker, memstick_check);
498 		host->dev.class = &memstick_host_class;
499 		host->dev.parent = dev;
500 		device_initialize(&host->dev);
501 	}
502 	return host;
503 }
504 EXPORT_SYMBOL(memstick_alloc_host);
505 
506 /**
507  * memstick_add_host - start request processing on memstick host
508  * @host - host to use
509  */
510 int memstick_add_host(struct memstick_host *host)
511 {
512 	int rc;
513 
514 	while (1) {
515 		if (!idr_pre_get(&memstick_host_idr, GFP_KERNEL))
516 			return -ENOMEM;
517 
518 		spin_lock(&memstick_host_lock);
519 		rc = idr_get_new(&memstick_host_idr, host, &host->id);
520 		spin_unlock(&memstick_host_lock);
521 		if (!rc)
522 			break;
523 		else if (rc != -EAGAIN)
524 			return rc;
525 	}
526 
527 	dev_set_name(&host->dev, "memstick%u", host->id);
528 
529 	rc = device_add(&host->dev);
530 	if (rc) {
531 		spin_lock(&memstick_host_lock);
532 		idr_remove(&memstick_host_idr, host->id);
533 		spin_unlock(&memstick_host_lock);
534 		return rc;
535 	}
536 
537 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
538 	memstick_detect_change(host);
539 	return 0;
540 }
541 EXPORT_SYMBOL(memstick_add_host);
542 
543 /**
544  * memstick_remove_host - stop request processing on memstick host
545  * @host - host to use
546  */
547 void memstick_remove_host(struct memstick_host *host)
548 {
549 	flush_workqueue(workqueue);
550 	mutex_lock(&host->lock);
551 	if (host->card)
552 		device_unregister(&host->card->dev);
553 	host->card = NULL;
554 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
555 	mutex_unlock(&host->lock);
556 
557 	spin_lock(&memstick_host_lock);
558 	idr_remove(&memstick_host_idr, host->id);
559 	spin_unlock(&memstick_host_lock);
560 	device_del(&host->dev);
561 }
562 EXPORT_SYMBOL(memstick_remove_host);
563 
564 /**
565  * memstick_free_host - free memstick host
566  * @host - host to use
567  */
568 void memstick_free_host(struct memstick_host *host)
569 {
570 	mutex_destroy(&host->lock);
571 	put_device(&host->dev);
572 }
573 EXPORT_SYMBOL(memstick_free_host);
574 
575 /**
576  * memstick_suspend_host - notify bus driver of host suspension
577  * @host - host to use
578  */
579 void memstick_suspend_host(struct memstick_host *host)
580 {
581 	mutex_lock(&host->lock);
582 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
583 	mutex_unlock(&host->lock);
584 }
585 EXPORT_SYMBOL(memstick_suspend_host);
586 
587 /**
588  * memstick_resume_host - notify bus driver of host resumption
589  * @host - host to use
590  */
591 void memstick_resume_host(struct memstick_host *host)
592 {
593 	int rc = 0;
594 
595 	mutex_lock(&host->lock);
596 	if (host->card)
597 		rc = memstick_power_on(host);
598 	mutex_unlock(&host->lock);
599 
600 	if (!rc)
601 		memstick_detect_change(host);
602 }
603 EXPORT_SYMBOL(memstick_resume_host);
604 
605 int memstick_register_driver(struct memstick_driver *drv)
606 {
607 	drv->driver.bus = &memstick_bus_type;
608 
609 	return driver_register(&drv->driver);
610 }
611 EXPORT_SYMBOL(memstick_register_driver);
612 
613 void memstick_unregister_driver(struct memstick_driver *drv)
614 {
615 	driver_unregister(&drv->driver);
616 }
617 EXPORT_SYMBOL(memstick_unregister_driver);
618 
619 
620 static int __init memstick_init(void)
621 {
622 	int rc;
623 
624 	workqueue = create_freezable_workqueue("kmemstick");
625 	if (!workqueue)
626 		return -ENOMEM;
627 
628 	rc = bus_register(&memstick_bus_type);
629 	if (!rc)
630 		rc = class_register(&memstick_host_class);
631 
632 	if (!rc)
633 		return 0;
634 
635 	bus_unregister(&memstick_bus_type);
636 	destroy_workqueue(workqueue);
637 
638 	return rc;
639 }
640 
641 static void __exit memstick_exit(void)
642 {
643 	class_unregister(&memstick_host_class);
644 	bus_unregister(&memstick_bus_type);
645 	destroy_workqueue(workqueue);
646 	idr_destroy(&memstick_host_idr);
647 }
648 
649 module_init(memstick_init);
650 module_exit(memstick_exit);
651 
652 MODULE_AUTHOR("Alex Dubov");
653 MODULE_LICENSE("GPL");
654 MODULE_DESCRIPTION("Sony MemoryStick core driver");
655