xref: /linux/drivers/memstick/core/memstick.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Sony MemoryStick support
4  *
5  *  Copyright (C) 2007 Alex Dubov <oakad@yahoo.com>
6  *
7  * Special thanks to Carlos Corbacho for providing various MemoryStick cards
8  * that made this driver possible.
9  */
10 
11 #include <linux/memstick.h>
12 #include <linux/idr.h>
13 #include <linux/fs.h>
14 #include <linux/delay.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/pm_runtime.h>
18 
19 #define DRIVER_NAME "memstick"
20 
21 static unsigned int cmd_retries = 3;
22 module_param(cmd_retries, uint, 0644);
23 
24 static struct workqueue_struct *workqueue;
25 static DEFINE_IDR(memstick_host_idr);
26 static DEFINE_SPINLOCK(memstick_host_lock);
27 
28 static int memstick_dev_match(struct memstick_dev *card,
29 			      const struct memstick_device_id *id)
30 {
31 	if (id->match_flags & MEMSTICK_MATCH_ALL) {
32 		if ((id->type == card->id.type)
33 		    && (id->category == card->id.category)
34 		    && (id->class == card->id.class))
35 			return 1;
36 	}
37 
38 	return 0;
39 }
40 
41 static int memstick_bus_match(struct device *dev, const struct device_driver *drv)
42 {
43 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
44 						 dev);
45 	const struct memstick_driver *ms_drv = container_of_const(drv, struct memstick_driver,
46 								  driver);
47 	const struct memstick_device_id *ids = ms_drv->id_table;
48 
49 	if (ids) {
50 		while (ids->match_flags) {
51 			if (memstick_dev_match(card, ids))
52 				return 1;
53 			++ids;
54 		}
55 	}
56 	return 0;
57 }
58 
59 static int memstick_uevent(const struct device *dev, struct kobj_uevent_env *env)
60 {
61 	const struct memstick_dev *card = container_of_const(dev, struct memstick_dev,
62 							     dev);
63 
64 	if (add_uevent_var(env, "MEMSTICK_TYPE=%02X", card->id.type))
65 		return -ENOMEM;
66 
67 	if (add_uevent_var(env, "MEMSTICK_CATEGORY=%02X", card->id.category))
68 		return -ENOMEM;
69 
70 	if (add_uevent_var(env, "MEMSTICK_CLASS=%02X", card->id.class))
71 		return -ENOMEM;
72 
73 	return 0;
74 }
75 
76 static int memstick_device_probe(struct device *dev)
77 {
78 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
79 						 dev);
80 	struct memstick_driver *drv = container_of(dev->driver,
81 						   struct memstick_driver,
82 						   driver);
83 	int rc = -ENODEV;
84 
85 	if (dev->driver && drv->probe) {
86 		rc = drv->probe(card);
87 		if (!rc)
88 			get_device(dev);
89 	}
90 	return rc;
91 }
92 
93 static void memstick_device_remove(struct device *dev)
94 {
95 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
96 						  dev);
97 	struct memstick_driver *drv = container_of(dev->driver,
98 						   struct memstick_driver,
99 						   driver);
100 
101 	if (dev->driver && drv->remove) {
102 		drv->remove(card);
103 		card->dev.driver = NULL;
104 	}
105 
106 	put_device(dev);
107 }
108 
109 #ifdef CONFIG_PM
110 
111 static int memstick_device_suspend(struct device *dev, pm_message_t state)
112 {
113 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
114 						  dev);
115 	struct memstick_driver *drv = container_of(dev->driver,
116 						   struct memstick_driver,
117 						   driver);
118 
119 	if (dev->driver && drv->suspend)
120 		return drv->suspend(card, state);
121 	return 0;
122 }
123 
124 static int memstick_device_resume(struct device *dev)
125 {
126 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
127 						  dev);
128 	struct memstick_driver *drv = container_of(dev->driver,
129 						   struct memstick_driver,
130 						   driver);
131 
132 	if (dev->driver && drv->resume)
133 		return drv->resume(card);
134 	return 0;
135 }
136 
137 #else
138 
139 #define memstick_device_suspend NULL
140 #define memstick_device_resume NULL
141 
142 #endif /* CONFIG_PM */
143 
144 #define MEMSTICK_ATTR(name, format)                                           \
145 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, \
146 			    char *buf)                                        \
147 {                                                                             \
148 	struct memstick_dev *card = container_of(dev, struct memstick_dev,    \
149 						 dev);                        \
150 	return sprintf(buf, format, card->id.name);                           \
151 }                                                                             \
152 static DEVICE_ATTR_RO(name);
153 
154 MEMSTICK_ATTR(type, "%02X");
155 MEMSTICK_ATTR(category, "%02X");
156 MEMSTICK_ATTR(class, "%02X");
157 
158 static struct attribute *memstick_dev_attrs[] = {
159 	&dev_attr_type.attr,
160 	&dev_attr_category.attr,
161 	&dev_attr_class.attr,
162 	NULL,
163 };
164 ATTRIBUTE_GROUPS(memstick_dev);
165 
166 static const struct bus_type memstick_bus_type = {
167 	.name           = "memstick",
168 	.dev_groups	= memstick_dev_groups,
169 	.match          = memstick_bus_match,
170 	.uevent         = memstick_uevent,
171 	.probe          = memstick_device_probe,
172 	.remove         = memstick_device_remove,
173 	.suspend        = memstick_device_suspend,
174 	.resume         = memstick_device_resume
175 };
176 
177 static void memstick_free(struct device *dev)
178 {
179 	struct memstick_host *host = container_of(dev, struct memstick_host,
180 						  dev);
181 	kfree(host);
182 }
183 
184 static struct class memstick_host_class = {
185 	.name        = "memstick_host",
186 	.dev_release = memstick_free
187 };
188 
189 static void memstick_free_card(struct device *dev)
190 {
191 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
192 						 dev);
193 	kfree(card);
194 }
195 
196 static int memstick_dummy_check(struct memstick_dev *card)
197 {
198 	return 0;
199 }
200 
201 /**
202  * memstick_detect_change - schedule media detection on memstick host
203  * @host: host to use
204  */
205 void memstick_detect_change(struct memstick_host *host)
206 {
207 	queue_work(workqueue, &host->media_checker);
208 }
209 EXPORT_SYMBOL(memstick_detect_change);
210 
211 /**
212  * memstick_next_req - called by host driver to obtain next request to process
213  * @host: host to use
214  * @mrq: pointer to stick the request to
215  *
216  * Host calls this function from idle state (*mrq == NULL) or after finishing
217  * previous request (*mrq should point to it). If previous request was
218  * unsuccessful, it is retried for predetermined number of times.
219  *
220  * Returns: value of 0 means that new request was assigned to the host.
221  * Otherwise a negative error code is returned.
222  */
223 int memstick_next_req(struct memstick_host *host, struct memstick_request **mrq)
224 {
225 	int rc = -ENXIO;
226 
227 	if ((*mrq) && (*mrq)->error && host->retries) {
228 		(*mrq)->error = rc;
229 		host->retries--;
230 		return 0;
231 	}
232 
233 	if (host->card && host->card->next_request)
234 		rc = host->card->next_request(host->card, mrq);
235 
236 	if (!rc)
237 		host->retries = cmd_retries > 1 ? cmd_retries - 1 : 1;
238 	else
239 		*mrq = NULL;
240 
241 	return rc;
242 }
243 EXPORT_SYMBOL(memstick_next_req);
244 
245 /**
246  * memstick_new_req - notify the host that some requests are pending
247  * @host: host to use
248  */
249 void memstick_new_req(struct memstick_host *host)
250 {
251 	if (host->card) {
252 		host->retries = cmd_retries;
253 		reinit_completion(&host->card->mrq_complete);
254 		host->request(host);
255 	}
256 }
257 EXPORT_SYMBOL(memstick_new_req);
258 
259 /**
260  * memstick_init_req_sg - set request fields needed for bulk data transfer
261  * @mrq: request to use
262  * @tpc: memstick Transport Protocol Command
263  * @sg: TPC argument
264  */
265 void memstick_init_req_sg(struct memstick_request *mrq, unsigned char tpc,
266 			  const struct scatterlist *sg)
267 {
268 	mrq->tpc = tpc;
269 	if (tpc & 8)
270 		mrq->data_dir = WRITE;
271 	else
272 		mrq->data_dir = READ;
273 
274 	mrq->sg = *sg;
275 	mrq->long_data = 1;
276 
277 	if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
278 		mrq->need_card_int = 1;
279 	else
280 		mrq->need_card_int = 0;
281 }
282 EXPORT_SYMBOL(memstick_init_req_sg);
283 
284 /**
285  * memstick_init_req - set request fields needed for short data transfer
286  * @mrq: request to use
287  * @tpc: memstick Transport Protocol Command
288  * @buf: TPC argument buffer
289  * @length: TPC argument size
290  *
291  * The intended use of this function (transfer of data items several bytes
292  * in size) allows us to just copy the value between request structure and
293  * user supplied buffer.
294  */
295 void memstick_init_req(struct memstick_request *mrq, unsigned char tpc,
296 		       const void *buf, size_t length)
297 {
298 	mrq->tpc = tpc;
299 	if (tpc & 8)
300 		mrq->data_dir = WRITE;
301 	else
302 		mrq->data_dir = READ;
303 
304 	mrq->data_len = length > sizeof(mrq->data) ? sizeof(mrq->data) : length;
305 	if (mrq->data_dir == WRITE)
306 		memcpy(mrq->data, buf, mrq->data_len);
307 
308 	mrq->long_data = 0;
309 
310 	if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
311 		mrq->need_card_int = 1;
312 	else
313 		mrq->need_card_int = 0;
314 }
315 EXPORT_SYMBOL(memstick_init_req);
316 
317 /*
318  * Functions prefixed with "h_" are protocol callbacks. They can be called from
319  * interrupt context. Return value of 0 means that request processing is still
320  * ongoing, while special error value of -EAGAIN means that current request is
321  * finished (and request processor should come back some time later).
322  */
323 
324 static int h_memstick_read_dev_id(struct memstick_dev *card,
325 				  struct memstick_request **mrq)
326 {
327 	struct ms_id_register id_reg = {};
328 
329 	if (!(*mrq)) {
330 		memstick_init_req(&card->current_mrq, MS_TPC_READ_REG, &id_reg,
331 				  sizeof(struct ms_id_register));
332 		*mrq = &card->current_mrq;
333 		return 0;
334 	}
335 	if (!(*mrq)->error) {
336 		memcpy(&id_reg, (*mrq)->data, sizeof(id_reg));
337 		card->id.match_flags = MEMSTICK_MATCH_ALL;
338 		card->id.type = id_reg.type;
339 		card->id.category = id_reg.category;
340 		card->id.class = id_reg.class;
341 		dev_dbg(&card->dev, "if_mode = %02x\n", id_reg.if_mode);
342 	}
343 	complete(&card->mrq_complete);
344 	return -EAGAIN;
345 }
346 
347 static int h_memstick_set_rw_addr(struct memstick_dev *card,
348 				  struct memstick_request **mrq)
349 {
350 	if (!(*mrq)) {
351 		memstick_init_req(&card->current_mrq, MS_TPC_SET_RW_REG_ADRS,
352 				  (char *)&card->reg_addr,
353 				  sizeof(card->reg_addr));
354 		*mrq = &card->current_mrq;
355 		return 0;
356 	} else {
357 		complete(&card->mrq_complete);
358 		return -EAGAIN;
359 	}
360 }
361 
362 /**
363  * memstick_set_rw_addr - issue SET_RW_REG_ADDR request and wait for it to
364  *                        complete
365  * @card: media device to use
366  *
367  * Returns: error setting for the current request
368  */
369 int memstick_set_rw_addr(struct memstick_dev *card)
370 {
371 	card->next_request = h_memstick_set_rw_addr;
372 	memstick_new_req(card->host);
373 	if (!wait_for_completion_timeout(&card->mrq_complete,
374 			msecs_to_jiffies(500)))
375 		card->current_mrq.error = -ETIMEDOUT;
376 
377 	return card->current_mrq.error;
378 }
379 EXPORT_SYMBOL(memstick_set_rw_addr);
380 
381 static struct memstick_dev *memstick_alloc_card(struct memstick_host *host)
382 {
383 	struct memstick_dev *card = kzalloc(sizeof(struct memstick_dev),
384 					    GFP_KERNEL);
385 	struct memstick_dev *old_card = host->card;
386 	struct ms_id_register id_reg;
387 
388 	if (card) {
389 		card->host = host;
390 		dev_set_name(&card->dev, "%s", dev_name(&host->dev));
391 		card->dev.parent = &host->dev;
392 		card->dev.bus = &memstick_bus_type;
393 		card->dev.release = memstick_free_card;
394 		card->check = memstick_dummy_check;
395 
396 		card->reg_addr.r_offset = offsetof(struct ms_register, id);
397 		card->reg_addr.r_length = sizeof(id_reg);
398 		card->reg_addr.w_offset = offsetof(struct ms_register, id);
399 		card->reg_addr.w_length = sizeof(id_reg);
400 
401 		init_completion(&card->mrq_complete);
402 
403 		host->card = card;
404 		if (memstick_set_rw_addr(card))
405 			goto err_out;
406 
407 		card->next_request = h_memstick_read_dev_id;
408 		memstick_new_req(host);
409 		if (!wait_for_completion_timeout(&card->mrq_complete,
410 				msecs_to_jiffies(500)))
411 			card->current_mrq.error = -ETIMEDOUT;
412 
413 		if (card->current_mrq.error)
414 			goto err_out;
415 	}
416 	host->card = old_card;
417 	return card;
418 err_out:
419 	host->card = old_card;
420 	kfree_const(card->dev.kobj.name);
421 	kfree(card);
422 	return NULL;
423 }
424 
425 static int memstick_power_on(struct memstick_host *host)
426 {
427 	int rc = host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_ON);
428 
429 	if (!rc)
430 		rc = host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
431 
432 	return rc;
433 }
434 
435 static void memstick_check(struct work_struct *work)
436 {
437 	struct memstick_host *host = container_of(work, struct memstick_host,
438 						  media_checker);
439 	struct memstick_dev *card;
440 
441 	dev_dbg(&host->dev, "memstick_check started\n");
442 	pm_runtime_get_noresume(host->dev.parent);
443 	mutex_lock(&host->lock);
444 	if (!host->card) {
445 		if (memstick_power_on(host))
446 			goto out_power_off;
447 	} else if (host->card->stop)
448 		host->card->stop(host->card);
449 
450 	if (host->removing)
451 		goto out_power_off;
452 
453 	card = memstick_alloc_card(host);
454 
455 	if (!card) {
456 		if (host->card) {
457 			device_unregister(&host->card->dev);
458 			host->card = NULL;
459 		}
460 	} else {
461 		dev_dbg(&host->dev, "new card %02x, %02x, %02x\n",
462 			card->id.type, card->id.category, card->id.class);
463 		if (host->card) {
464 			if (memstick_set_rw_addr(host->card)
465 			    || !memstick_dev_match(host->card, &card->id)
466 			    || !(host->card->check(host->card))) {
467 				device_unregister(&host->card->dev);
468 				host->card = NULL;
469 			} else if (host->card->start)
470 				host->card->start(host->card);
471 		}
472 
473 		if (!host->card) {
474 			host->card = card;
475 			if (device_register(&card->dev)) {
476 				put_device(&card->dev);
477 				host->card = NULL;
478 			}
479 		} else {
480 			kfree_const(card->dev.kobj.name);
481 			kfree(card);
482 		}
483 	}
484 
485 out_power_off:
486 	if (!host->card)
487 		host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
488 
489 	mutex_unlock(&host->lock);
490 	pm_runtime_put(host->dev.parent);
491 	dev_dbg(&host->dev, "memstick_check finished\n");
492 }
493 
494 /**
495  * memstick_alloc_host - allocate a memstick_host structure
496  * @extra: size of the user private data to allocate
497  * @dev: parent device of the host
498  *
499  * Returns: %NULL on failure or the allocated &memstick_host pointer on success
500  */
501 struct memstick_host *memstick_alloc_host(unsigned int extra,
502 					  struct device *dev)
503 {
504 	struct memstick_host *host;
505 
506 	host = kzalloc(sizeof(struct memstick_host) + extra, GFP_KERNEL);
507 	if (host) {
508 		mutex_init(&host->lock);
509 		INIT_WORK(&host->media_checker, memstick_check);
510 		host->dev.class = &memstick_host_class;
511 		host->dev.parent = dev;
512 		device_initialize(&host->dev);
513 	}
514 	return host;
515 }
516 EXPORT_SYMBOL(memstick_alloc_host);
517 
518 /**
519  * memstick_add_host - start request processing on memstick host
520  * @host: host to use
521  *
522  * Returns: %0 on success or a negative error code on failure
523  */
524 int memstick_add_host(struct memstick_host *host)
525 {
526 	int rc;
527 
528 	idr_preload(GFP_KERNEL);
529 	spin_lock(&memstick_host_lock);
530 
531 	rc = idr_alloc(&memstick_host_idr, host, 0, 0, GFP_NOWAIT);
532 	if (rc >= 0)
533 		host->id = rc;
534 
535 	spin_unlock(&memstick_host_lock);
536 	idr_preload_end();
537 	if (rc < 0)
538 		return rc;
539 
540 	dev_set_name(&host->dev, "memstick%u", host->id);
541 
542 	rc = device_add(&host->dev);
543 	if (rc) {
544 		spin_lock(&memstick_host_lock);
545 		idr_remove(&memstick_host_idr, host->id);
546 		spin_unlock(&memstick_host_lock);
547 		return rc;
548 	}
549 
550 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
551 	memstick_detect_change(host);
552 	return 0;
553 }
554 EXPORT_SYMBOL(memstick_add_host);
555 
556 /**
557  * memstick_remove_host - stop request processing on memstick host
558  * @host: host to use
559  */
560 void memstick_remove_host(struct memstick_host *host)
561 {
562 	flush_workqueue(workqueue);
563 	mutex_lock(&host->lock);
564 	if (host->card)
565 		device_unregister(&host->card->dev);
566 	host->card = NULL;
567 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
568 	mutex_unlock(&host->lock);
569 
570 	spin_lock(&memstick_host_lock);
571 	idr_remove(&memstick_host_idr, host->id);
572 	spin_unlock(&memstick_host_lock);
573 	device_del(&host->dev);
574 }
575 EXPORT_SYMBOL(memstick_remove_host);
576 
577 /**
578  * memstick_free_host - free memstick host
579  * @host: host to use
580  */
581 void memstick_free_host(struct memstick_host *host)
582 {
583 	mutex_destroy(&host->lock);
584 	put_device(&host->dev);
585 }
586 EXPORT_SYMBOL(memstick_free_host);
587 
588 /**
589  * memstick_suspend_host - notify bus driver of host suspension
590  * @host: host to use
591  */
592 void memstick_suspend_host(struct memstick_host *host)
593 {
594 	mutex_lock(&host->lock);
595 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
596 	mutex_unlock(&host->lock);
597 }
598 EXPORT_SYMBOL(memstick_suspend_host);
599 
600 /**
601  * memstick_resume_host - notify bus driver of host resumption
602  * @host: host to use
603  */
604 void memstick_resume_host(struct memstick_host *host)
605 {
606 	int rc = 0;
607 
608 	mutex_lock(&host->lock);
609 	if (host->card)
610 		rc = memstick_power_on(host);
611 	mutex_unlock(&host->lock);
612 
613 	if (!rc)
614 		memstick_detect_change(host);
615 }
616 EXPORT_SYMBOL(memstick_resume_host);
617 
618 int memstick_register_driver(struct memstick_driver *drv)
619 {
620 	drv->driver.bus = &memstick_bus_type;
621 
622 	return driver_register(&drv->driver);
623 }
624 EXPORT_SYMBOL(memstick_register_driver);
625 
626 void memstick_unregister_driver(struct memstick_driver *drv)
627 {
628 	driver_unregister(&drv->driver);
629 }
630 EXPORT_SYMBOL(memstick_unregister_driver);
631 
632 
633 static int __init memstick_init(void)
634 {
635 	int rc;
636 
637 	workqueue = create_freezable_workqueue("kmemstick");
638 	if (!workqueue)
639 		return -ENOMEM;
640 
641 	rc = bus_register(&memstick_bus_type);
642 	if (rc)
643 		goto error_destroy_workqueue;
644 
645 	rc = class_register(&memstick_host_class);
646 	if (rc)
647 		goto error_bus_unregister;
648 
649 	return 0;
650 
651 error_bus_unregister:
652 	bus_unregister(&memstick_bus_type);
653 error_destroy_workqueue:
654 	destroy_workqueue(workqueue);
655 
656 	return rc;
657 }
658 
659 static void __exit memstick_exit(void)
660 {
661 	class_unregister(&memstick_host_class);
662 	bus_unregister(&memstick_bus_type);
663 	destroy_workqueue(workqueue);
664 	idr_destroy(&memstick_host_idr);
665 }
666 
667 module_init(memstick_init);
668 module_exit(memstick_exit);
669 
670 MODULE_AUTHOR("Alex Dubov");
671 MODULE_LICENSE("GPL");
672 MODULE_DESCRIPTION("Sony MemoryStick core driver");
673