xref: /openbmc/linux/drivers/scsi/ses.c (revision 4bb1e4e7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * SCSI Enclosure Services
4  *
5  * Copyright (C) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
6  */
7 
8 #include <linux/slab.h>
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/enclosure.h>
12 #include <asm/unaligned.h>
13 
14 #include <scsi/scsi.h>
15 #include <scsi/scsi_cmnd.h>
16 #include <scsi/scsi_dbg.h>
17 #include <scsi/scsi_device.h>
18 #include <scsi/scsi_driver.h>
19 #include <scsi/scsi_host.h>
20 
21 #include <scsi/scsi_transport_sas.h>
22 
23 struct ses_device {
24 	unsigned char *page1;
25 	unsigned char *page1_types;
26 	unsigned char *page2;
27 	unsigned char *page10;
28 	short page1_len;
29 	short page1_num_types;
30 	short page2_len;
31 	short page10_len;
32 };
33 
34 struct ses_component {
35 	u64 addr;
36 };
37 
38 static bool ses_page2_supported(struct enclosure_device *edev)
39 {
40 	struct ses_device *ses_dev = edev->scratch;
41 
42 	return (ses_dev->page2 != NULL);
43 }
44 
45 static int ses_probe(struct device *dev)
46 {
47 	struct scsi_device *sdev = to_scsi_device(dev);
48 	int err = -ENODEV;
49 
50 	if (sdev->type != TYPE_ENCLOSURE)
51 		goto out;
52 
53 	err = 0;
54 	sdev_printk(KERN_NOTICE, sdev, "Attached Enclosure device\n");
55 
56  out:
57 	return err;
58 }
59 
60 #define SES_TIMEOUT (30 * HZ)
61 #define SES_RETRIES 3
62 
63 static void init_device_slot_control(unsigned char *dest_desc,
64 				     struct enclosure_component *ecomp,
65 				     unsigned char *status)
66 {
67 	memcpy(dest_desc, status, 4);
68 	dest_desc[0] = 0;
69 	/* only clear byte 1 for ENCLOSURE_COMPONENT_DEVICE */
70 	if (ecomp->type == ENCLOSURE_COMPONENT_DEVICE)
71 		dest_desc[1] = 0;
72 	dest_desc[2] &= 0xde;
73 	dest_desc[3] &= 0x3c;
74 }
75 
76 
77 static int ses_recv_diag(struct scsi_device *sdev, int page_code,
78 			 void *buf, int bufflen)
79 {
80 	int ret;
81 	unsigned char cmd[] = {
82 		RECEIVE_DIAGNOSTIC,
83 		1,		/* Set PCV bit */
84 		page_code,
85 		bufflen >> 8,
86 		bufflen & 0xff,
87 		0
88 	};
89 	unsigned char recv_page_code;
90 
91 	ret =  scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, bufflen,
92 				NULL, SES_TIMEOUT, SES_RETRIES, NULL);
93 	if (unlikely(ret))
94 		return ret;
95 
96 	recv_page_code = ((unsigned char *)buf)[0];
97 
98 	if (likely(recv_page_code == page_code))
99 		return ret;
100 
101 	/* successful diagnostic but wrong page code.  This happens to some
102 	 * USB devices, just print a message and pretend there was an error */
103 
104 	sdev_printk(KERN_ERR, sdev,
105 		    "Wrong diagnostic page; asked for %d got %u\n",
106 		    page_code, recv_page_code);
107 
108 	return -EINVAL;
109 }
110 
111 static int ses_send_diag(struct scsi_device *sdev, int page_code,
112 			 void *buf, int bufflen)
113 {
114 	u32 result;
115 
116 	unsigned char cmd[] = {
117 		SEND_DIAGNOSTIC,
118 		0x10,		/* Set PF bit */
119 		0,
120 		bufflen >> 8,
121 		bufflen & 0xff,
122 		0
123 	};
124 
125 	result = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, buf, bufflen,
126 				  NULL, SES_TIMEOUT, SES_RETRIES, NULL);
127 	if (result)
128 		sdev_printk(KERN_ERR, sdev, "SEND DIAGNOSTIC result: %8x\n",
129 			    result);
130 	return result;
131 }
132 
133 static int ses_set_page2_descriptor(struct enclosure_device *edev,
134 				      struct enclosure_component *ecomp,
135 				      unsigned char *desc)
136 {
137 	int i, j, count = 0, descriptor = ecomp->number;
138 	struct scsi_device *sdev = to_scsi_device(edev->edev.parent);
139 	struct ses_device *ses_dev = edev->scratch;
140 	unsigned char *type_ptr = ses_dev->page1_types;
141 	unsigned char *desc_ptr = ses_dev->page2 + 8;
142 
143 	/* Clear everything */
144 	memset(desc_ptr, 0, ses_dev->page2_len - 8);
145 	for (i = 0; i < ses_dev->page1_num_types; i++, type_ptr += 4) {
146 		for (j = 0; j < type_ptr[1]; j++) {
147 			desc_ptr += 4;
148 			if (type_ptr[0] != ENCLOSURE_COMPONENT_DEVICE &&
149 			    type_ptr[0] != ENCLOSURE_COMPONENT_ARRAY_DEVICE)
150 				continue;
151 			if (count++ == descriptor) {
152 				memcpy(desc_ptr, desc, 4);
153 				/* set select */
154 				desc_ptr[0] |= 0x80;
155 				/* clear reserved, just in case */
156 				desc_ptr[0] &= 0xf0;
157 			}
158 		}
159 	}
160 
161 	return ses_send_diag(sdev, 2, ses_dev->page2, ses_dev->page2_len);
162 }
163 
164 static unsigned char *ses_get_page2_descriptor(struct enclosure_device *edev,
165 				      struct enclosure_component *ecomp)
166 {
167 	int i, j, count = 0, descriptor = ecomp->number;
168 	struct scsi_device *sdev = to_scsi_device(edev->edev.parent);
169 	struct ses_device *ses_dev = edev->scratch;
170 	unsigned char *type_ptr = ses_dev->page1_types;
171 	unsigned char *desc_ptr = ses_dev->page2 + 8;
172 
173 	if (ses_recv_diag(sdev, 2, ses_dev->page2, ses_dev->page2_len) < 0)
174 		return NULL;
175 
176 	for (i = 0; i < ses_dev->page1_num_types; i++, type_ptr += 4) {
177 		for (j = 0; j < type_ptr[1]; j++) {
178 			desc_ptr += 4;
179 			if (type_ptr[0] != ENCLOSURE_COMPONENT_DEVICE &&
180 			    type_ptr[0] != ENCLOSURE_COMPONENT_ARRAY_DEVICE)
181 				continue;
182 			if (count++ == descriptor)
183 				return desc_ptr;
184 		}
185 	}
186 	return NULL;
187 }
188 
189 /* For device slot and array device slot elements, byte 3 bit 6
190  * is "fault sensed" while byte 3 bit 5 is "fault reqstd". As this
191  * code stands these bits are shifted 4 positions right so in
192  * sysfs they will appear as bits 2 and 1 respectively. Strange. */
193 static void ses_get_fault(struct enclosure_device *edev,
194 			  struct enclosure_component *ecomp)
195 {
196 	unsigned char *desc;
197 
198 	if (!ses_page2_supported(edev)) {
199 		ecomp->fault = 0;
200 		return;
201 	}
202 	desc = ses_get_page2_descriptor(edev, ecomp);
203 	if (desc)
204 		ecomp->fault = (desc[3] & 0x60) >> 4;
205 }
206 
207 static int ses_set_fault(struct enclosure_device *edev,
208 			  struct enclosure_component *ecomp,
209 			 enum enclosure_component_setting val)
210 {
211 	unsigned char desc[4];
212 	unsigned char *desc_ptr;
213 
214 	if (!ses_page2_supported(edev))
215 		return -EINVAL;
216 
217 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
218 
219 	if (!desc_ptr)
220 		return -EIO;
221 
222 	init_device_slot_control(desc, ecomp, desc_ptr);
223 
224 	switch (val) {
225 	case ENCLOSURE_SETTING_DISABLED:
226 		desc[3] &= 0xdf;
227 		break;
228 	case ENCLOSURE_SETTING_ENABLED:
229 		desc[3] |= 0x20;
230 		break;
231 	default:
232 		/* SES doesn't do the SGPIO blink settings */
233 		return -EINVAL;
234 	}
235 
236 	return ses_set_page2_descriptor(edev, ecomp, desc);
237 }
238 
239 static void ses_get_status(struct enclosure_device *edev,
240 			   struct enclosure_component *ecomp)
241 {
242 	unsigned char *desc;
243 
244 	if (!ses_page2_supported(edev)) {
245 		ecomp->status = 0;
246 		return;
247 	}
248 	desc = ses_get_page2_descriptor(edev, ecomp);
249 	if (desc)
250 		ecomp->status = (desc[0] & 0x0f);
251 }
252 
253 static void ses_get_locate(struct enclosure_device *edev,
254 			   struct enclosure_component *ecomp)
255 {
256 	unsigned char *desc;
257 
258 	if (!ses_page2_supported(edev)) {
259 		ecomp->locate = 0;
260 		return;
261 	}
262 	desc = ses_get_page2_descriptor(edev, ecomp);
263 	if (desc)
264 		ecomp->locate = (desc[2] & 0x02) ? 1 : 0;
265 }
266 
267 static int ses_set_locate(struct enclosure_device *edev,
268 			  struct enclosure_component *ecomp,
269 			  enum enclosure_component_setting val)
270 {
271 	unsigned char desc[4];
272 	unsigned char *desc_ptr;
273 
274 	if (!ses_page2_supported(edev))
275 		return -EINVAL;
276 
277 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
278 
279 	if (!desc_ptr)
280 		return -EIO;
281 
282 	init_device_slot_control(desc, ecomp, desc_ptr);
283 
284 	switch (val) {
285 	case ENCLOSURE_SETTING_DISABLED:
286 		desc[2] &= 0xfd;
287 		break;
288 	case ENCLOSURE_SETTING_ENABLED:
289 		desc[2] |= 0x02;
290 		break;
291 	default:
292 		/* SES doesn't do the SGPIO blink settings */
293 		return -EINVAL;
294 	}
295 	return ses_set_page2_descriptor(edev, ecomp, desc);
296 }
297 
298 static int ses_set_active(struct enclosure_device *edev,
299 			  struct enclosure_component *ecomp,
300 			  enum enclosure_component_setting val)
301 {
302 	unsigned char desc[4];
303 	unsigned char *desc_ptr;
304 
305 	if (!ses_page2_supported(edev))
306 		return -EINVAL;
307 
308 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
309 
310 	if (!desc_ptr)
311 		return -EIO;
312 
313 	init_device_slot_control(desc, ecomp, desc_ptr);
314 
315 	switch (val) {
316 	case ENCLOSURE_SETTING_DISABLED:
317 		desc[2] &= 0x7f;
318 		ecomp->active = 0;
319 		break;
320 	case ENCLOSURE_SETTING_ENABLED:
321 		desc[2] |= 0x80;
322 		ecomp->active = 1;
323 		break;
324 	default:
325 		/* SES doesn't do the SGPIO blink settings */
326 		return -EINVAL;
327 	}
328 	return ses_set_page2_descriptor(edev, ecomp, desc);
329 }
330 
331 static int ses_show_id(struct enclosure_device *edev, char *buf)
332 {
333 	struct ses_device *ses_dev = edev->scratch;
334 	unsigned long long id = get_unaligned_be64(ses_dev->page1+8+4);
335 
336 	return sprintf(buf, "%#llx\n", id);
337 }
338 
339 static void ses_get_power_status(struct enclosure_device *edev,
340 				 struct enclosure_component *ecomp)
341 {
342 	unsigned char *desc;
343 
344 	if (!ses_page2_supported(edev)) {
345 		ecomp->power_status = 0;
346 		return;
347 	}
348 
349 	desc = ses_get_page2_descriptor(edev, ecomp);
350 	if (desc)
351 		ecomp->power_status = (desc[3] & 0x10) ? 0 : 1;
352 }
353 
354 static int ses_set_power_status(struct enclosure_device *edev,
355 				struct enclosure_component *ecomp,
356 				int val)
357 {
358 	unsigned char desc[4];
359 	unsigned char *desc_ptr;
360 
361 	if (!ses_page2_supported(edev))
362 		return -EINVAL;
363 
364 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
365 
366 	if (!desc_ptr)
367 		return -EIO;
368 
369 	init_device_slot_control(desc, ecomp, desc_ptr);
370 
371 	switch (val) {
372 	/* power = 1 is device_off = 0 and vice versa */
373 	case 0:
374 		desc[3] |= 0x10;
375 		break;
376 	case 1:
377 		desc[3] &= 0xef;
378 		break;
379 	default:
380 		return -EINVAL;
381 	}
382 	ecomp->power_status = val;
383 	return ses_set_page2_descriptor(edev, ecomp, desc);
384 }
385 
386 static struct enclosure_component_callbacks ses_enclosure_callbacks = {
387 	.get_fault		= ses_get_fault,
388 	.set_fault		= ses_set_fault,
389 	.get_status		= ses_get_status,
390 	.get_locate		= ses_get_locate,
391 	.set_locate		= ses_set_locate,
392 	.get_power_status	= ses_get_power_status,
393 	.set_power_status	= ses_set_power_status,
394 	.set_active		= ses_set_active,
395 	.show_id		= ses_show_id,
396 };
397 
398 struct ses_host_edev {
399 	struct Scsi_Host *shost;
400 	struct enclosure_device *edev;
401 };
402 
403 #if 0
404 int ses_match_host(struct enclosure_device *edev, void *data)
405 {
406 	struct ses_host_edev *sed = data;
407 	struct scsi_device *sdev;
408 
409 	if (!scsi_is_sdev_device(edev->edev.parent))
410 		return 0;
411 
412 	sdev = to_scsi_device(edev->edev.parent);
413 
414 	if (sdev->host != sed->shost)
415 		return 0;
416 
417 	sed->edev = edev;
418 	return 1;
419 }
420 #endif  /*  0  */
421 
422 static void ses_process_descriptor(struct enclosure_component *ecomp,
423 				   unsigned char *desc)
424 {
425 	int eip = desc[0] & 0x10;
426 	int invalid = desc[0] & 0x80;
427 	enum scsi_protocol proto = desc[0] & 0x0f;
428 	u64 addr = 0;
429 	int slot = -1;
430 	struct ses_component *scomp = ecomp->scratch;
431 	unsigned char *d;
432 
433 	if (invalid)
434 		return;
435 
436 	switch (proto) {
437 	case SCSI_PROTOCOL_FCP:
438 		if (eip) {
439 			d = desc + 4;
440 			slot = d[3];
441 		}
442 		break;
443 	case SCSI_PROTOCOL_SAS:
444 		if (eip) {
445 			d = desc + 4;
446 			slot = d[3];
447 			d = desc + 8;
448 		} else
449 			d = desc + 4;
450 		/* only take the phy0 addr */
451 		addr = (u64)d[12] << 56 |
452 			(u64)d[13] << 48 |
453 			(u64)d[14] << 40 |
454 			(u64)d[15] << 32 |
455 			(u64)d[16] << 24 |
456 			(u64)d[17] << 16 |
457 			(u64)d[18] << 8 |
458 			(u64)d[19];
459 		break;
460 	default:
461 		/* FIXME: Need to add more protocols than just SAS */
462 		break;
463 	}
464 	ecomp->slot = slot;
465 	scomp->addr = addr;
466 }
467 
468 struct efd {
469 	u64 addr;
470 	struct device *dev;
471 };
472 
473 static int ses_enclosure_find_by_addr(struct enclosure_device *edev,
474 				      void *data)
475 {
476 	struct efd *efd = data;
477 	int i;
478 	struct ses_component *scomp;
479 
480 	if (!edev->component[0].scratch)
481 		return 0;
482 
483 	for (i = 0; i < edev->components; i++) {
484 		scomp = edev->component[i].scratch;
485 		if (scomp->addr != efd->addr)
486 			continue;
487 
488 		if (enclosure_add_device(edev, i, efd->dev) == 0)
489 			kobject_uevent(&efd->dev->kobj, KOBJ_CHANGE);
490 		return 1;
491 	}
492 	return 0;
493 }
494 
495 #define INIT_ALLOC_SIZE 32
496 
497 static void ses_enclosure_data_process(struct enclosure_device *edev,
498 				       struct scsi_device *sdev,
499 				       int create)
500 {
501 	u32 result;
502 	unsigned char *buf = NULL, *type_ptr, *desc_ptr, *addl_desc_ptr = NULL;
503 	int i, j, page7_len, len, components;
504 	struct ses_device *ses_dev = edev->scratch;
505 	int types = ses_dev->page1_num_types;
506 	unsigned char *hdr_buf = kzalloc(INIT_ALLOC_SIZE, GFP_KERNEL);
507 
508 	if (!hdr_buf)
509 		goto simple_populate;
510 
511 	/* re-read page 10 */
512 	if (ses_dev->page10)
513 		ses_recv_diag(sdev, 10, ses_dev->page10, ses_dev->page10_len);
514 	/* Page 7 for the descriptors is optional */
515 	result = ses_recv_diag(sdev, 7, hdr_buf, INIT_ALLOC_SIZE);
516 	if (result)
517 		goto simple_populate;
518 
519 	page7_len = len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
520 	/* add 1 for trailing '\0' we'll use */
521 	buf = kzalloc(len + 1, GFP_KERNEL);
522 	if (!buf)
523 		goto simple_populate;
524 	result = ses_recv_diag(sdev, 7, buf, len);
525 	if (result) {
526  simple_populate:
527 		kfree(buf);
528 		buf = NULL;
529 		desc_ptr = NULL;
530 		len = 0;
531 		page7_len = 0;
532 	} else {
533 		desc_ptr = buf + 8;
534 		len = (desc_ptr[2] << 8) + desc_ptr[3];
535 		/* skip past overall descriptor */
536 		desc_ptr += len + 4;
537 	}
538 	if (ses_dev->page10)
539 		addl_desc_ptr = ses_dev->page10 + 8;
540 	type_ptr = ses_dev->page1_types;
541 	components = 0;
542 	for (i = 0; i < types; i++, type_ptr += 4) {
543 		for (j = 0; j < type_ptr[1]; j++) {
544 			char *name = NULL;
545 			struct enclosure_component *ecomp;
546 
547 			if (desc_ptr) {
548 				if (desc_ptr >= buf + page7_len) {
549 					desc_ptr = NULL;
550 				} else {
551 					len = (desc_ptr[2] << 8) + desc_ptr[3];
552 					desc_ptr += 4;
553 					/* Add trailing zero - pushes into
554 					 * reserved space */
555 					desc_ptr[len] = '\0';
556 					name = desc_ptr;
557 				}
558 			}
559 			if (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
560 			    type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE) {
561 
562 				if (create)
563 					ecomp =	enclosure_component_alloc(
564 						edev,
565 						components++,
566 						type_ptr[0],
567 						name);
568 				else
569 					ecomp = &edev->component[components++];
570 
571 				if (!IS_ERR(ecomp)) {
572 					if (addl_desc_ptr)
573 						ses_process_descriptor(
574 							ecomp,
575 							addl_desc_ptr);
576 					if (create)
577 						enclosure_component_register(
578 							ecomp);
579 				}
580 			}
581 			if (desc_ptr)
582 				desc_ptr += len;
583 
584 			if (addl_desc_ptr &&
585 			    /* only find additional descriptions for specific devices */
586 			    (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
587 			     type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE ||
588 			     type_ptr[0] == ENCLOSURE_COMPONENT_SAS_EXPANDER ||
589 			     /* these elements are optional */
590 			     type_ptr[0] == ENCLOSURE_COMPONENT_SCSI_TARGET_PORT ||
591 			     type_ptr[0] == ENCLOSURE_COMPONENT_SCSI_INITIATOR_PORT ||
592 			     type_ptr[0] == ENCLOSURE_COMPONENT_CONTROLLER_ELECTRONICS))
593 				addl_desc_ptr += addl_desc_ptr[1] + 2;
594 
595 		}
596 	}
597 	kfree(buf);
598 	kfree(hdr_buf);
599 }
600 
601 static void ses_match_to_enclosure(struct enclosure_device *edev,
602 				   struct scsi_device *sdev,
603 				   int refresh)
604 {
605 	struct scsi_device *edev_sdev = to_scsi_device(edev->edev.parent);
606 	struct efd efd = {
607 		.addr = 0,
608 	};
609 
610 	if (refresh)
611 		ses_enclosure_data_process(edev, edev_sdev, 0);
612 
613 	if (scsi_is_sas_rphy(sdev->sdev_target->dev.parent))
614 		efd.addr = sas_get_address(sdev);
615 
616 	if (efd.addr) {
617 		efd.dev = &sdev->sdev_gendev;
618 
619 		enclosure_for_each_device(ses_enclosure_find_by_addr, &efd);
620 	}
621 }
622 
623 static int ses_intf_add(struct device *cdev,
624 			struct class_interface *intf)
625 {
626 	struct scsi_device *sdev = to_scsi_device(cdev->parent);
627 	struct scsi_device *tmp_sdev;
628 	unsigned char *buf = NULL, *hdr_buf, *type_ptr, page;
629 	struct ses_device *ses_dev;
630 	u32 result;
631 	int i, types, len, components = 0;
632 	int err = -ENOMEM;
633 	int num_enclosures;
634 	struct enclosure_device *edev;
635 	struct ses_component *scomp = NULL;
636 
637 	if (!scsi_device_enclosure(sdev)) {
638 		/* not an enclosure, but might be in one */
639 		struct enclosure_device *prev = NULL;
640 
641 		while ((edev = enclosure_find(&sdev->host->shost_gendev, prev)) != NULL) {
642 			ses_match_to_enclosure(edev, sdev, 1);
643 			prev = edev;
644 		}
645 		return -ENODEV;
646 	}
647 
648 	/* TYPE_ENCLOSURE prints a message in probe */
649 	if (sdev->type != TYPE_ENCLOSURE)
650 		sdev_printk(KERN_NOTICE, sdev, "Embedded Enclosure Device\n");
651 
652 	ses_dev = kzalloc(sizeof(*ses_dev), GFP_KERNEL);
653 	hdr_buf = kzalloc(INIT_ALLOC_SIZE, GFP_KERNEL);
654 	if (!hdr_buf || !ses_dev)
655 		goto err_init_free;
656 
657 	page = 1;
658 	result = ses_recv_diag(sdev, page, hdr_buf, INIT_ALLOC_SIZE);
659 	if (result)
660 		goto recv_failed;
661 
662 	len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
663 	buf = kzalloc(len, GFP_KERNEL);
664 	if (!buf)
665 		goto err_free;
666 
667 	result = ses_recv_diag(sdev, page, buf, len);
668 	if (result)
669 		goto recv_failed;
670 
671 	types = 0;
672 
673 	/* we always have one main enclosure and the rest are referred
674 	 * to as secondary subenclosures */
675 	num_enclosures = buf[1] + 1;
676 
677 	/* begin at the enclosure descriptor */
678 	type_ptr = buf + 8;
679 	/* skip all the enclosure descriptors */
680 	for (i = 0; i < num_enclosures && type_ptr < buf + len; i++) {
681 		types += type_ptr[2];
682 		type_ptr += type_ptr[3] + 4;
683 	}
684 
685 	ses_dev->page1_types = type_ptr;
686 	ses_dev->page1_num_types = types;
687 
688 	for (i = 0; i < types && type_ptr < buf + len; i++, type_ptr += 4) {
689 		if (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
690 		    type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE)
691 			components += type_ptr[1];
692 	}
693 	ses_dev->page1 = buf;
694 	ses_dev->page1_len = len;
695 	buf = NULL;
696 
697 	page = 2;
698 	result = ses_recv_diag(sdev, page, hdr_buf, INIT_ALLOC_SIZE);
699 	if (result)
700 		goto page2_not_supported;
701 
702 	len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
703 	buf = kzalloc(len, GFP_KERNEL);
704 	if (!buf)
705 		goto err_free;
706 
707 	/* make sure getting page 2 actually works */
708 	result = ses_recv_diag(sdev, 2, buf, len);
709 	if (result)
710 		goto recv_failed;
711 	ses_dev->page2 = buf;
712 	ses_dev->page2_len = len;
713 	buf = NULL;
714 
715 	/* The additional information page --- allows us
716 	 * to match up the devices */
717 	page = 10;
718 	result = ses_recv_diag(sdev, page, hdr_buf, INIT_ALLOC_SIZE);
719 	if (!result) {
720 
721 		len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
722 		buf = kzalloc(len, GFP_KERNEL);
723 		if (!buf)
724 			goto err_free;
725 
726 		result = ses_recv_diag(sdev, page, buf, len);
727 		if (result)
728 			goto recv_failed;
729 		ses_dev->page10 = buf;
730 		ses_dev->page10_len = len;
731 		buf = NULL;
732 	}
733 page2_not_supported:
734 	scomp = kcalloc(components, sizeof(struct ses_component), GFP_KERNEL);
735 	if (!scomp)
736 		goto err_free;
737 
738 	edev = enclosure_register(cdev->parent, dev_name(&sdev->sdev_gendev),
739 				  components, &ses_enclosure_callbacks);
740 	if (IS_ERR(edev)) {
741 		err = PTR_ERR(edev);
742 		goto err_free;
743 	}
744 
745 	kfree(hdr_buf);
746 
747 	edev->scratch = ses_dev;
748 	for (i = 0; i < components; i++)
749 		edev->component[i].scratch = scomp + i;
750 
751 	ses_enclosure_data_process(edev, sdev, 1);
752 
753 	/* see if there are any devices matching before
754 	 * we found the enclosure */
755 	shost_for_each_device(tmp_sdev, sdev->host) {
756 		if (tmp_sdev->lun != 0 || scsi_device_enclosure(tmp_sdev))
757 			continue;
758 		ses_match_to_enclosure(edev, tmp_sdev, 0);
759 	}
760 
761 	return 0;
762 
763  recv_failed:
764 	sdev_printk(KERN_ERR, sdev, "Failed to get diagnostic page 0x%x\n",
765 		    page);
766 	err = -ENODEV;
767  err_free:
768 	kfree(buf);
769 	kfree(scomp);
770 	kfree(ses_dev->page10);
771 	kfree(ses_dev->page2);
772 	kfree(ses_dev->page1);
773  err_init_free:
774 	kfree(ses_dev);
775 	kfree(hdr_buf);
776 	sdev_printk(KERN_ERR, sdev, "Failed to bind enclosure %d\n", err);
777 	return err;
778 }
779 
780 static int ses_remove(struct device *dev)
781 {
782 	return 0;
783 }
784 
785 static void ses_intf_remove_component(struct scsi_device *sdev)
786 {
787 	struct enclosure_device *edev, *prev = NULL;
788 
789 	while ((edev = enclosure_find(&sdev->host->shost_gendev, prev)) != NULL) {
790 		prev = edev;
791 		if (!enclosure_remove_device(edev, &sdev->sdev_gendev))
792 			break;
793 	}
794 	if (edev)
795 		put_device(&edev->edev);
796 }
797 
798 static void ses_intf_remove_enclosure(struct scsi_device *sdev)
799 {
800 	struct enclosure_device *edev;
801 	struct ses_device *ses_dev;
802 
803 	/*  exact match to this enclosure */
804 	edev = enclosure_find(&sdev->sdev_gendev, NULL);
805 	if (!edev)
806 		return;
807 
808 	ses_dev = edev->scratch;
809 	edev->scratch = NULL;
810 
811 	kfree(ses_dev->page10);
812 	kfree(ses_dev->page1);
813 	kfree(ses_dev->page2);
814 	kfree(ses_dev);
815 
816 	kfree(edev->component[0].scratch);
817 
818 	put_device(&edev->edev);
819 	enclosure_unregister(edev);
820 }
821 
822 static void ses_intf_remove(struct device *cdev,
823 			    struct class_interface *intf)
824 {
825 	struct scsi_device *sdev = to_scsi_device(cdev->parent);
826 
827 	if (!scsi_device_enclosure(sdev))
828 		ses_intf_remove_component(sdev);
829 	else
830 		ses_intf_remove_enclosure(sdev);
831 }
832 
833 static struct class_interface ses_interface = {
834 	.add_dev	= ses_intf_add,
835 	.remove_dev	= ses_intf_remove,
836 };
837 
838 static struct scsi_driver ses_template = {
839 	.gendrv = {
840 		.name		= "ses",
841 		.owner		= THIS_MODULE,
842 		.probe		= ses_probe,
843 		.remove		= ses_remove,
844 	},
845 };
846 
847 static int __init ses_init(void)
848 {
849 	int err;
850 
851 	err = scsi_register_interface(&ses_interface);
852 	if (err)
853 		return err;
854 
855 	err = scsi_register_driver(&ses_template.gendrv);
856 	if (err)
857 		goto out_unreg;
858 
859 	return 0;
860 
861  out_unreg:
862 	scsi_unregister_interface(&ses_interface);
863 	return err;
864 }
865 
866 static void __exit ses_exit(void)
867 {
868 	scsi_unregister_driver(&ses_template.gendrv);
869 	scsi_unregister_interface(&ses_interface);
870 }
871 
872 module_init(ses_init);
873 module_exit(ses_exit);
874 
875 MODULE_ALIAS_SCSI_DEVICE(TYPE_ENCLOSURE);
876 
877 MODULE_AUTHOR("James Bottomley");
878 MODULE_DESCRIPTION("SCSI Enclosure Services (ses) driver");
879 MODULE_LICENSE("GPL v2");
880