xref: /openbmc/linux/drivers/memstick/core/memstick.c (revision dfe94d40)
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 			      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, struct device_driver *drv)
42 {
43 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
44 						 dev);
45 	struct memstick_driver *ms_drv = container_of(drv,
46 						      struct memstick_driver,
47 						      driver);
48 	struct memstick_device_id *ids = ms_drv->id_table;
49 
50 	if (ids) {
51 		while (ids->match_flags) {
52 			if (memstick_dev_match(card, ids))
53 				return 1;
54 			++ids;
55 		}
56 	}
57 	return 0;
58 }
59 
60 static int memstick_uevent(struct device *dev, struct kobj_uevent_env *env)
61 {
62 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
63 						  dev);
64 
65 	if (add_uevent_var(env, "MEMSTICK_TYPE=%02X", card->id.type))
66 		return -ENOMEM;
67 
68 	if (add_uevent_var(env, "MEMSTICK_CATEGORY=%02X", card->id.category))
69 		return -ENOMEM;
70 
71 	if (add_uevent_var(env, "MEMSTICK_CLASS=%02X", card->id.class))
72 		return -ENOMEM;
73 
74 	return 0;
75 }
76 
77 static int memstick_device_probe(struct device *dev)
78 {
79 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
80 						 dev);
81 	struct memstick_driver *drv = container_of(dev->driver,
82 						   struct memstick_driver,
83 						   driver);
84 	int rc = -ENODEV;
85 
86 	if (dev->driver && drv->probe) {
87 		rc = drv->probe(card);
88 		if (!rc)
89 			get_device(dev);
90 	}
91 	return rc;
92 }
93 
94 static int memstick_device_remove(struct device *dev)
95 {
96 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
97 						  dev);
98 	struct memstick_driver *drv = container_of(dev->driver,
99 						   struct memstick_driver,
100 						   driver);
101 
102 	if (dev->driver && drv->remove) {
103 		drv->remove(card);
104 		card->dev.driver = NULL;
105 	}
106 
107 	put_device(dev);
108 	return 0;
109 }
110 
111 #ifdef CONFIG_PM
112 
113 static int memstick_device_suspend(struct device *dev, pm_message_t state)
114 {
115 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
116 						  dev);
117 	struct memstick_driver *drv = container_of(dev->driver,
118 						   struct memstick_driver,
119 						   driver);
120 
121 	if (dev->driver && drv->suspend)
122 		return drv->suspend(card, state);
123 	return 0;
124 }
125 
126 static int memstick_device_resume(struct device *dev)
127 {
128 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
129 						  dev);
130 	struct memstick_driver *drv = container_of(dev->driver,
131 						   struct memstick_driver,
132 						   driver);
133 
134 	if (dev->driver && drv->resume)
135 		return drv->resume(card);
136 	return 0;
137 }
138 
139 #else
140 
141 #define memstick_device_suspend NULL
142 #define memstick_device_resume NULL
143 
144 #endif /* CONFIG_PM */
145 
146 #define MEMSTICK_ATTR(name, format)                                           \
147 static ssize_t name##_show(struct device *dev, struct device_attribute *attr, \
148 			    char *buf)                                        \
149 {                                                                             \
150 	struct memstick_dev *card = container_of(dev, struct memstick_dev,    \
151 						 dev);                        \
152 	return sprintf(buf, format, card->id.name);                           \
153 }                                                                             \
154 static DEVICE_ATTR_RO(name);
155 
156 MEMSTICK_ATTR(type, "%02X");
157 MEMSTICK_ATTR(category, "%02X");
158 MEMSTICK_ATTR(class, "%02X");
159 
160 static struct attribute *memstick_dev_attrs[] = {
161 	&dev_attr_type.attr,
162 	&dev_attr_category.attr,
163 	&dev_attr_class.attr,
164 	NULL,
165 };
166 ATTRIBUTE_GROUPS(memstick_dev);
167 
168 static struct bus_type memstick_bus_type = {
169 	.name           = "memstick",
170 	.dev_groups	= memstick_dev_groups,
171 	.match          = memstick_bus_match,
172 	.uevent         = memstick_uevent,
173 	.probe          = memstick_device_probe,
174 	.remove         = memstick_device_remove,
175 	.suspend        = memstick_device_suspend,
176 	.resume         = memstick_device_resume
177 };
178 
179 static void memstick_free(struct device *dev)
180 {
181 	struct memstick_host *host = container_of(dev, struct memstick_host,
182 						  dev);
183 	kfree(host);
184 }
185 
186 static struct class memstick_host_class = {
187 	.name        = "memstick_host",
188 	.dev_release = memstick_free
189 };
190 
191 static void memstick_free_card(struct device *dev)
192 {
193 	struct memstick_dev *card = container_of(dev, struct memstick_dev,
194 						 dev);
195 	kfree(card);
196 }
197 
198 static int memstick_dummy_check(struct memstick_dev *card)
199 {
200 	return 0;
201 }
202 
203 /**
204  * memstick_detect_change - schedule media detection on memstick host
205  * @host - host to use
206  */
207 void memstick_detect_change(struct memstick_host *host)
208 {
209 	queue_work(workqueue, &host->media_checker);
210 }
211 EXPORT_SYMBOL(memstick_detect_change);
212 
213 /**
214  * memstick_next_req - called by host driver to obtain next request to process
215  * @host - host to use
216  * @mrq - pointer to stick the request to
217  *
218  * Host calls this function from idle state (*mrq == NULL) or after finishing
219  * previous request (*mrq should point to it). If previous request was
220  * unsuccessful, it is retried for predetermined number of times. Return value
221  * of 0 means that new request was assigned to the host.
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 	} else {
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 
348 static int h_memstick_set_rw_addr(struct memstick_dev *card,
349 				  struct memstick_request **mrq)
350 {
351 	if (!(*mrq)) {
352 		memstick_init_req(&card->current_mrq, MS_TPC_SET_RW_REG_ADRS,
353 				  (char *)&card->reg_addr,
354 				  sizeof(card->reg_addr));
355 		*mrq = &card->current_mrq;
356 		return 0;
357 	} else {
358 		complete(&card->mrq_complete);
359 		return -EAGAIN;
360 	}
361 }
362 
363 /**
364  * memstick_set_rw_addr - issue SET_RW_REG_ADDR request and wait for it to
365  *                        complete
366  * @card - media device to use
367  */
368 int memstick_set_rw_addr(struct memstick_dev *card)
369 {
370 	card->next_request = h_memstick_set_rw_addr;
371 	memstick_new_req(card->host);
372 	wait_for_completion(&card->mrq_complete);
373 
374 	return card->current_mrq.error;
375 }
376 EXPORT_SYMBOL(memstick_set_rw_addr);
377 
378 static struct memstick_dev *memstick_alloc_card(struct memstick_host *host)
379 {
380 	struct memstick_dev *card = kzalloc(sizeof(struct memstick_dev),
381 					    GFP_KERNEL);
382 	struct memstick_dev *old_card = host->card;
383 	struct ms_id_register id_reg;
384 
385 	if (card) {
386 		card->host = host;
387 		dev_set_name(&card->dev, "%s", dev_name(&host->dev));
388 		card->dev.parent = &host->dev;
389 		card->dev.bus = &memstick_bus_type;
390 		card->dev.release = memstick_free_card;
391 		card->check = memstick_dummy_check;
392 
393 		card->reg_addr.r_offset = offsetof(struct ms_register, id);
394 		card->reg_addr.r_length = sizeof(id_reg);
395 		card->reg_addr.w_offset = offsetof(struct ms_register, id);
396 		card->reg_addr.w_length = sizeof(id_reg);
397 
398 		init_completion(&card->mrq_complete);
399 
400 		host->card = card;
401 		if (memstick_set_rw_addr(card))
402 			goto err_out;
403 
404 		card->next_request = h_memstick_read_dev_id;
405 		memstick_new_req(host);
406 		wait_for_completion(&card->mrq_complete);
407 
408 		if (card->current_mrq.error)
409 			goto err_out;
410 	}
411 	host->card = old_card;
412 	return card;
413 err_out:
414 	host->card = old_card;
415 	kfree(card);
416 	return NULL;
417 }
418 
419 static int memstick_power_on(struct memstick_host *host)
420 {
421 	int rc = host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_ON);
422 
423 	if (!rc)
424 		rc = host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
425 
426 	return rc;
427 }
428 
429 static void memstick_check(struct work_struct *work)
430 {
431 	struct memstick_host *host = container_of(work, struct memstick_host,
432 						  media_checker);
433 	struct memstick_dev *card;
434 
435 	dev_dbg(&host->dev, "memstick_check started\n");
436 	pm_runtime_get_noresume(host->dev.parent);
437 	mutex_lock(&host->lock);
438 	if (!host->card) {
439 		if (memstick_power_on(host))
440 			goto out_power_off;
441 	} else if (host->card->stop)
442 		host->card->stop(host->card);
443 
444 	if (host->removing)
445 		goto out_power_off;
446 
447 	card = memstick_alloc_card(host);
448 
449 	if (!card) {
450 		if (host->card) {
451 			device_unregister(&host->card->dev);
452 			host->card = NULL;
453 		}
454 	} else {
455 		dev_dbg(&host->dev, "new card %02x, %02x, %02x\n",
456 			card->id.type, card->id.category, card->id.class);
457 		if (host->card) {
458 			if (memstick_set_rw_addr(host->card)
459 			    || !memstick_dev_match(host->card, &card->id)
460 			    || !(host->card->check(host->card))) {
461 				device_unregister(&host->card->dev);
462 				host->card = NULL;
463 			} else if (host->card->start)
464 				host->card->start(host->card);
465 		}
466 
467 		if (!host->card) {
468 			host->card = card;
469 			if (device_register(&card->dev)) {
470 				put_device(&card->dev);
471 				host->card = NULL;
472 			}
473 		} else
474 			kfree(card);
475 	}
476 
477 out_power_off:
478 	if (!host->card)
479 		host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
480 
481 	mutex_unlock(&host->lock);
482 	pm_runtime_put(host->dev.parent);
483 	dev_dbg(&host->dev, "memstick_check finished\n");
484 }
485 
486 /**
487  * memstick_alloc_host - allocate a memstick_host structure
488  * @extra: size of the user private data to allocate
489  * @dev: parent device of the host
490  */
491 struct memstick_host *memstick_alloc_host(unsigned int extra,
492 					  struct device *dev)
493 {
494 	struct memstick_host *host;
495 
496 	host = kzalloc(sizeof(struct memstick_host) + extra, GFP_KERNEL);
497 	if (host) {
498 		mutex_init(&host->lock);
499 		INIT_WORK(&host->media_checker, memstick_check);
500 		host->dev.class = &memstick_host_class;
501 		host->dev.parent = dev;
502 		device_initialize(&host->dev);
503 	}
504 	return host;
505 }
506 EXPORT_SYMBOL(memstick_alloc_host);
507 
508 /**
509  * memstick_add_host - start request processing on memstick host
510  * @host - host to use
511  */
512 int memstick_add_host(struct memstick_host *host)
513 {
514 	int rc;
515 
516 	idr_preload(GFP_KERNEL);
517 	spin_lock(&memstick_host_lock);
518 
519 	rc = idr_alloc(&memstick_host_idr, host, 0, 0, GFP_NOWAIT);
520 	if (rc >= 0)
521 		host->id = rc;
522 
523 	spin_unlock(&memstick_host_lock);
524 	idr_preload_end();
525 	if (rc < 0)
526 		return rc;
527 
528 	dev_set_name(&host->dev, "memstick%u", host->id);
529 
530 	rc = device_add(&host->dev);
531 	if (rc) {
532 		spin_lock(&memstick_host_lock);
533 		idr_remove(&memstick_host_idr, host->id);
534 		spin_unlock(&memstick_host_lock);
535 		return rc;
536 	}
537 
538 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
539 	memstick_detect_change(host);
540 	return 0;
541 }
542 EXPORT_SYMBOL(memstick_add_host);
543 
544 /**
545  * memstick_remove_host - stop request processing on memstick host
546  * @host - host to use
547  */
548 void memstick_remove_host(struct memstick_host *host)
549 {
550 	host->removing = 1;
551 	flush_workqueue(workqueue);
552 	mutex_lock(&host->lock);
553 	if (host->card)
554 		device_unregister(&host->card->dev);
555 	host->card = NULL;
556 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
557 	mutex_unlock(&host->lock);
558 
559 	spin_lock(&memstick_host_lock);
560 	idr_remove(&memstick_host_idr, host->id);
561 	spin_unlock(&memstick_host_lock);
562 	device_del(&host->dev);
563 }
564 EXPORT_SYMBOL(memstick_remove_host);
565 
566 /**
567  * memstick_free_host - free memstick host
568  * @host - host to use
569  */
570 void memstick_free_host(struct memstick_host *host)
571 {
572 	mutex_destroy(&host->lock);
573 	put_device(&host->dev);
574 }
575 EXPORT_SYMBOL(memstick_free_host);
576 
577 /**
578  * memstick_suspend_host - notify bus driver of host suspension
579  * @host - host to use
580  */
581 void memstick_suspend_host(struct memstick_host *host)
582 {
583 	mutex_lock(&host->lock);
584 	host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
585 	mutex_unlock(&host->lock);
586 }
587 EXPORT_SYMBOL(memstick_suspend_host);
588 
589 /**
590  * memstick_resume_host - notify bus driver of host resumption
591  * @host - host to use
592  */
593 void memstick_resume_host(struct memstick_host *host)
594 {
595 	int rc = 0;
596 
597 	mutex_lock(&host->lock);
598 	if (host->card)
599 		rc = memstick_power_on(host);
600 	mutex_unlock(&host->lock);
601 
602 	if (!rc)
603 		memstick_detect_change(host);
604 }
605 EXPORT_SYMBOL(memstick_resume_host);
606 
607 int memstick_register_driver(struct memstick_driver *drv)
608 {
609 	drv->driver.bus = &memstick_bus_type;
610 
611 	return driver_register(&drv->driver);
612 }
613 EXPORT_SYMBOL(memstick_register_driver);
614 
615 void memstick_unregister_driver(struct memstick_driver *drv)
616 {
617 	driver_unregister(&drv->driver);
618 }
619 EXPORT_SYMBOL(memstick_unregister_driver);
620 
621 
622 static int __init memstick_init(void)
623 {
624 	int rc;
625 
626 	workqueue = create_freezable_workqueue("kmemstick");
627 	if (!workqueue)
628 		return -ENOMEM;
629 
630 	rc = bus_register(&memstick_bus_type);
631 	if (rc)
632 		goto error_destroy_workqueue;
633 
634 	rc = class_register(&memstick_host_class);
635 	if (rc)
636 		goto error_bus_unregister;
637 
638 	return 0;
639 
640 error_bus_unregister:
641 	bus_unregister(&memstick_bus_type);
642 error_destroy_workqueue:
643 	destroy_workqueue(workqueue);
644 
645 	return rc;
646 }
647 
648 static void __exit memstick_exit(void)
649 {
650 	class_unregister(&memstick_host_class);
651 	bus_unregister(&memstick_bus_type);
652 	destroy_workqueue(workqueue);
653 	idr_destroy(&memstick_host_idr);
654 }
655 
656 module_init(memstick_init);
657 module_exit(memstick_exit);
658 
659 MODULE_AUTHOR("Alex Dubov");
660 MODULE_LICENSE("GPL");
661 MODULE_DESCRIPTION("Sony MemoryStick core driver");
662