xref: /openbmc/linux/drivers/misc/mei/init.c (revision 95e9fd10)
1 /*
2  *
3  * Intel Management Engine Interface (Intel MEI) Linux driver
4  * Copyright (c) 2003-2012, Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  */
16 
17 #include <linux/pci.h>
18 #include <linux/sched.h>
19 #include <linux/wait.h>
20 #include <linux/delay.h>
21 
22 #include "mei_dev.h"
23 #include "hw.h"
24 #include "interface.h"
25 #include <linux/mei.h>
26 
27 const uuid_le mei_amthi_guid  = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d, 0xac,
28 						0xa8, 0x46, 0xe0, 0xff, 0x65,
29 						0x81, 0x4c);
30 
31 /**
32  * mei_io_list_init - Sets up a queue list.
33  *
34  * @list: An instance io list structure
35  * @dev: the device structure
36  */
37 void mei_io_list_init(struct mei_io_list *list)
38 {
39 	/* initialize our queue list */
40 	INIT_LIST_HEAD(&list->mei_cb.cb_list);
41 }
42 
43 /**
44  * mei_io_list_flush - removes list entry belonging to cl.
45  *
46  * @list:  An instance of our list structure
47  * @cl: private data of the file object
48  */
49 void mei_io_list_flush(struct mei_io_list *list, struct mei_cl *cl)
50 {
51 	struct mei_cl_cb *pos;
52 	struct mei_cl_cb *next;
53 
54 	list_for_each_entry_safe(pos, next, &list->mei_cb.cb_list, cb_list) {
55 		if (pos->file_private) {
56 			struct mei_cl *cl_tmp;
57 			cl_tmp = (struct mei_cl *)pos->file_private;
58 			if (mei_cl_cmp_id(cl, cl_tmp))
59 				list_del(&pos->cb_list);
60 		}
61 	}
62 }
63 /**
64  * mei_cl_flush_queues - flushes queue lists belonging to cl.
65  *
66  * @dev: the device structure
67  * @cl: private data of the file object
68  */
69 int mei_cl_flush_queues(struct mei_cl *cl)
70 {
71 	if (!cl || !cl->dev)
72 		return -EINVAL;
73 
74 	dev_dbg(&cl->dev->pdev->dev, "remove list entry belonging to cl\n");
75 	mei_io_list_flush(&cl->dev->read_list, cl);
76 	mei_io_list_flush(&cl->dev->write_list, cl);
77 	mei_io_list_flush(&cl->dev->write_waiting_list, cl);
78 	mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
79 	mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
80 	mei_io_list_flush(&cl->dev->amthi_cmd_list, cl);
81 	mei_io_list_flush(&cl->dev->amthi_read_complete_list, cl);
82 	return 0;
83 }
84 
85 
86 
87 /**
88  * mei_reset_iamthif_params - initializes mei device iamthif
89  *
90  * @dev: the device structure
91  */
92 static void mei_reset_iamthif_params(struct mei_device *dev)
93 {
94 	/* reset iamthif parameters. */
95 	dev->iamthif_current_cb = NULL;
96 	dev->iamthif_msg_buf_size = 0;
97 	dev->iamthif_msg_buf_index = 0;
98 	dev->iamthif_canceled = false;
99 	dev->iamthif_ioctl = false;
100 	dev->iamthif_state = MEI_IAMTHIF_IDLE;
101 	dev->iamthif_timer = 0;
102 }
103 
104 /**
105  * init_mei_device - allocates and initializes the mei device structure
106  *
107  * @pdev: The pci device structure
108  *
109  * returns The mei_device_device pointer on success, NULL on failure.
110  */
111 struct mei_device *mei_device_init(struct pci_dev *pdev)
112 {
113 	struct mei_device *dev;
114 
115 	dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
116 	if (!dev)
117 		return NULL;
118 
119 	/* setup our list array */
120 	INIT_LIST_HEAD(&dev->file_list);
121 	INIT_LIST_HEAD(&dev->wd_cl.link);
122 	INIT_LIST_HEAD(&dev->iamthif_cl.link);
123 	mutex_init(&dev->device_lock);
124 	init_waitqueue_head(&dev->wait_recvd_msg);
125 	init_waitqueue_head(&dev->wait_stop_wd);
126 	dev->mei_state = MEI_INITIALIZING;
127 	dev->iamthif_state = MEI_IAMTHIF_IDLE;
128 	dev->wd_interface_reg = false;
129 
130 
131 	mei_io_list_init(&dev->read_list);
132 	mei_io_list_init(&dev->write_list);
133 	mei_io_list_init(&dev->write_waiting_list);
134 	mei_io_list_init(&dev->ctrl_wr_list);
135 	mei_io_list_init(&dev->ctrl_rd_list);
136 	mei_io_list_init(&dev->amthi_cmd_list);
137 	mei_io_list_init(&dev->amthi_read_complete_list);
138 	dev->pdev = pdev;
139 	return dev;
140 }
141 
142 /**
143  * mei_hw_init - initializes host and fw to start work.
144  *
145  * @dev: the device structure
146  *
147  * returns 0 on success, <0 on failure.
148  */
149 int mei_hw_init(struct mei_device *dev)
150 {
151 	int err = 0;
152 	int ret;
153 
154 	mutex_lock(&dev->device_lock);
155 
156 	dev->host_hw_state = mei_hcsr_read(dev);
157 	dev->me_hw_state = mei_mecsr_read(dev);
158 	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
159 	    dev->host_hw_state, dev->me_hw_state);
160 
161 	/* acknowledge interrupt and stop interupts */
162 	if ((dev->host_hw_state & H_IS) == H_IS)
163 		mei_reg_write(dev, H_CSR, dev->host_hw_state);
164 
165 	/* Doesn't change in runtime */
166 	dev->hbuf_depth = (dev->host_hw_state & H_CBD) >> 24;
167 
168 	dev->recvd_msg = false;
169 	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
170 
171 	mei_reset(dev, 1);
172 
173 	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
174 	    dev->host_hw_state, dev->me_hw_state);
175 
176 	/* wait for ME to turn on ME_RDY */
177 	if (!dev->recvd_msg) {
178 		mutex_unlock(&dev->device_lock);
179 		err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
180 			dev->recvd_msg, MEI_INTEROP_TIMEOUT);
181 		mutex_lock(&dev->device_lock);
182 	}
183 
184 	if (err <= 0 && !dev->recvd_msg) {
185 		dev->mei_state = MEI_DISABLED;
186 		dev_dbg(&dev->pdev->dev,
187 			"wait_event_interruptible_timeout failed"
188 			"on wait for ME to turn on ME_RDY.\n");
189 		ret = -ENODEV;
190 		goto out;
191 	}
192 
193 	if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
194 	      ((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
195 		dev->mei_state = MEI_DISABLED;
196 		dev_dbg(&dev->pdev->dev,
197 			"host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
198 			dev->host_hw_state, dev->me_hw_state);
199 
200 		if (!(dev->host_hw_state & H_RDY))
201 			dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");
202 
203 		if (!(dev->me_hw_state & ME_RDY_HRA))
204 			dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");
205 
206 		dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
207 		ret = -ENODEV;
208 		goto out;
209 	}
210 
211 	if (dev->version.major_version != HBM_MAJOR_VERSION ||
212 	    dev->version.minor_version != HBM_MINOR_VERSION) {
213 		dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
214 		ret = -ENODEV;
215 		goto out;
216 	}
217 
218 	dev->recvd_msg = false;
219 	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
220 	    dev->host_hw_state, dev->me_hw_state);
221 	dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
222 	dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
223 	dev_dbg(&dev->pdev->dev, "MEI  start success.\n");
224 	ret = 0;
225 
226 out:
227 	mutex_unlock(&dev->device_lock);
228 	return ret;
229 }
230 
231 /**
232  * mei_hw_reset - resets fw via mei csr register.
233  *
234  * @dev: the device structure
235  * @interrupts_enabled: if interrupt should be enabled after reset.
236  */
237 static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
238 {
239 	dev->host_hw_state |= (H_RST | H_IG);
240 
241 	if (interrupts_enabled)
242 		mei_enable_interrupts(dev);
243 	else
244 		mei_disable_interrupts(dev);
245 }
246 
247 /**
248  * mei_reset - resets host and fw.
249  *
250  * @dev: the device structure
251  * @interrupts_enabled: if interrupt should be enabled after reset.
252  */
253 void mei_reset(struct mei_device *dev, int interrupts_enabled)
254 {
255 	struct mei_cl *cl_pos = NULL;
256 	struct mei_cl *cl_next = NULL;
257 	struct mei_cl_cb *cb_pos = NULL;
258 	struct mei_cl_cb *cb_next = NULL;
259 	bool unexpected;
260 
261 	if (dev->mei_state == MEI_RECOVERING_FROM_RESET) {
262 		dev->need_reset = true;
263 		return;
264 	}
265 
266 	unexpected = (dev->mei_state != MEI_INITIALIZING &&
267 			dev->mei_state != MEI_DISABLED &&
268 			dev->mei_state != MEI_POWER_DOWN &&
269 			dev->mei_state != MEI_POWER_UP);
270 
271 	dev->host_hw_state = mei_hcsr_read(dev);
272 
273 	dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
274 	    dev->host_hw_state);
275 
276 	mei_hw_reset(dev, interrupts_enabled);
277 
278 	dev->host_hw_state &= ~H_RST;
279 	dev->host_hw_state |= H_IG;
280 
281 	mei_hcsr_set(dev);
282 
283 	dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
284 	    dev->host_hw_state);
285 
286 	dev->need_reset = false;
287 
288 	if (dev->mei_state != MEI_INITIALIZING) {
289 		if (dev->mei_state != MEI_DISABLED &&
290 		    dev->mei_state != MEI_POWER_DOWN)
291 			dev->mei_state = MEI_RESETING;
292 
293 		list_for_each_entry_safe(cl_pos,
294 				cl_next, &dev->file_list, link) {
295 			cl_pos->state = MEI_FILE_DISCONNECTED;
296 			cl_pos->mei_flow_ctrl_creds = 0;
297 			cl_pos->read_cb = NULL;
298 			cl_pos->timer_count = 0;
299 		}
300 		/* remove entry if already in list */
301 		dev_dbg(&dev->pdev->dev, "list del iamthif and wd file list.\n");
302 		mei_remove_client_from_file_list(dev,
303 				dev->wd_cl.host_client_id);
304 
305 		mei_remove_client_from_file_list(dev,
306 				dev->iamthif_cl.host_client_id);
307 
308 		mei_reset_iamthif_params(dev);
309 		dev->extra_write_index = 0;
310 	}
311 
312 	dev->me_clients_num = 0;
313 	dev->rd_msg_hdr = 0;
314 	dev->stop = false;
315 	dev->wd_pending = false;
316 
317 	/* update the state of the registers after reset */
318 	dev->host_hw_state = mei_hcsr_read(dev);
319 	dev->me_hw_state = mei_mecsr_read(dev);
320 
321 	dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
322 	    dev->host_hw_state, dev->me_hw_state);
323 
324 	if (unexpected)
325 		dev_warn(&dev->pdev->dev, "unexpected reset.\n");
326 
327 	/* Wake up all readings so they can be interrupted */
328 	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
329 		if (waitqueue_active(&cl_pos->rx_wait)) {
330 			dev_dbg(&dev->pdev->dev, "Waking up client!\n");
331 			wake_up_interruptible(&cl_pos->rx_wait);
332 		}
333 	}
334 	/* remove all waiting requests */
335 	list_for_each_entry_safe(cb_pos, cb_next,
336 			&dev->write_list.mei_cb.cb_list, cb_list) {
337 		list_del(&cb_pos->cb_list);
338 		mei_free_cb_private(cb_pos);
339 	}
340 }
341 
342 
343 
344 /**
345  * host_start_message - mei host sends start message.
346  *
347  * @dev: the device structure
348  *
349  * returns none.
350  */
351 void mei_host_start_message(struct mei_device *dev)
352 {
353 	struct mei_msg_hdr *mei_hdr;
354 	struct hbm_host_version_request *host_start_req;
355 
356 	/* host start message */
357 	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
358 	mei_hdr->host_addr = 0;
359 	mei_hdr->me_addr = 0;
360 	mei_hdr->length = sizeof(struct hbm_host_version_request);
361 	mei_hdr->msg_complete = 1;
362 	mei_hdr->reserved = 0;
363 
364 	host_start_req =
365 	    (struct hbm_host_version_request *) &dev->wr_msg_buf[1];
366 	memset(host_start_req, 0, sizeof(struct hbm_host_version_request));
367 	host_start_req->hbm_cmd = HOST_START_REQ_CMD;
368 	host_start_req->host_version.major_version = HBM_MAJOR_VERSION;
369 	host_start_req->host_version.minor_version = HBM_MINOR_VERSION;
370 	dev->recvd_msg = false;
371 	if (mei_write_message(dev, mei_hdr, (unsigned char *)host_start_req,
372 				       mei_hdr->length)) {
373 		dev_dbg(&dev->pdev->dev, "write send version message to FW fail.\n");
374 		dev->mei_state = MEI_RESETING;
375 		mei_reset(dev, 1);
376 	}
377 	dev->init_clients_state = MEI_START_MESSAGE;
378 	dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
379 	return ;
380 }
381 
382 /**
383  * host_enum_clients_message - host sends enumeration client request message.
384  *
385  * @dev: the device structure
386  *
387  * returns none.
388  */
389 void mei_host_enum_clients_message(struct mei_device *dev)
390 {
391 	struct mei_msg_hdr *mei_hdr;
392 	struct hbm_host_enum_request *host_enum_req;
393 	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
394 	/* enumerate clients */
395 	mei_hdr->host_addr = 0;
396 	mei_hdr->me_addr = 0;
397 	mei_hdr->length = sizeof(struct hbm_host_enum_request);
398 	mei_hdr->msg_complete = 1;
399 	mei_hdr->reserved = 0;
400 
401 	host_enum_req = (struct hbm_host_enum_request *) &dev->wr_msg_buf[1];
402 	memset(host_enum_req, 0, sizeof(struct hbm_host_enum_request));
403 	host_enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
404 	if (mei_write_message(dev, mei_hdr, (unsigned char *)host_enum_req,
405 				mei_hdr->length)) {
406 		dev->mei_state = MEI_RESETING;
407 		dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
408 		mei_reset(dev, 1);
409 	}
410 	dev->init_clients_state = MEI_ENUM_CLIENTS_MESSAGE;
411 	dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
412 	return;
413 }
414 
415 
416 /**
417  * allocate_me_clients_storage - allocates storage for me clients
418  *
419  * @dev: the device structure
420  *
421  * returns none.
422  */
423 void mei_allocate_me_clients_storage(struct mei_device *dev)
424 {
425 	struct mei_me_client *clients;
426 	int b;
427 
428 	/* count how many ME clients we have */
429 	for_each_set_bit(b, dev->me_clients_map, MEI_CLIENTS_MAX)
430 		dev->me_clients_num++;
431 
432 	if (dev->me_clients_num <= 0)
433 		return ;
434 
435 
436 	if (dev->me_clients != NULL) {
437 		kfree(dev->me_clients);
438 		dev->me_clients = NULL;
439 	}
440 	dev_dbg(&dev->pdev->dev, "memory allocation for ME clients size=%zd.\n",
441 		dev->me_clients_num * sizeof(struct mei_me_client));
442 	/* allocate storage for ME clients representation */
443 	clients = kcalloc(dev->me_clients_num,
444 			sizeof(struct mei_me_client), GFP_KERNEL);
445 	if (!clients) {
446 		dev_dbg(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
447 		dev->mei_state = MEI_RESETING;
448 		mei_reset(dev, 1);
449 		return ;
450 	}
451 	dev->me_clients = clients;
452 	return ;
453 }
454 /**
455  * host_client_properties - reads properties for client
456  *
457  * @dev: the device structure
458  *
459  * returns:
460  * 	< 0 - Error.
461  *  = 0 - no more clients.
462  *  = 1 - still have clients to send properties request.
463  */
464 int mei_host_client_properties(struct mei_device *dev)
465 {
466 	struct mei_msg_hdr *mei_header;
467 	struct hbm_props_request *host_cli_req;
468 	int b;
469 	u8 client_num = dev->me_client_presentation_num;
470 
471 	b = dev->me_client_index;
472 	b = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, b);
473 	if (b < MEI_CLIENTS_MAX) {
474 		dev->me_clients[client_num].client_id = b;
475 		dev->me_clients[client_num].mei_flow_ctrl_creds = 0;
476 		mei_header = (struct mei_msg_hdr *)&dev->wr_msg_buf[0];
477 		mei_header->host_addr = 0;
478 		mei_header->me_addr = 0;
479 		mei_header->length = sizeof(struct hbm_props_request);
480 		mei_header->msg_complete = 1;
481 		mei_header->reserved = 0;
482 
483 		host_cli_req = (struct hbm_props_request *)&dev->wr_msg_buf[1];
484 
485 		memset(host_cli_req, 0, sizeof(struct hbm_props_request));
486 
487 		host_cli_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
488 		host_cli_req->address = b;
489 
490 		if (mei_write_message(dev, mei_header,
491 				(unsigned char *)host_cli_req,
492 				mei_header->length)) {
493 			dev->mei_state = MEI_RESETING;
494 			dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
495 			mei_reset(dev, 1);
496 			return -EIO;
497 		}
498 
499 		dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
500 		dev->me_client_index = b;
501 		return 1;
502 	}
503 
504 	return 0;
505 }
506 
507 /**
508  * mei_init_file_private - initializes private file structure.
509  *
510  * @priv: private file structure to be initialized
511  * @file: the file structure
512  */
513 void mei_cl_init(struct mei_cl *priv, struct mei_device *dev)
514 {
515 	memset(priv, 0, sizeof(struct mei_cl));
516 	init_waitqueue_head(&priv->wait);
517 	init_waitqueue_head(&priv->rx_wait);
518 	init_waitqueue_head(&priv->tx_wait);
519 	INIT_LIST_HEAD(&priv->link);
520 	priv->reading_state = MEI_IDLE;
521 	priv->writing_state = MEI_IDLE;
522 	priv->dev = dev;
523 }
524 
525 int mei_find_me_client_index(const struct mei_device *dev, uuid_le cuuid)
526 {
527 	int i, res = -1;
528 
529 	for (i = 0; i < dev->me_clients_num; ++i)
530 		if (uuid_le_cmp(cuuid,
531 				dev->me_clients[i].props.protocol_name) == 0) {
532 			res = i;
533 			break;
534 		}
535 
536 	return res;
537 }
538 
539 
540 /**
541  * mei_find_me_client_update_filext - searches for ME client guid
542  *                       sets client_id in mei_file_private if found
543  * @dev: the device structure
544  * @priv: private file structure to set client_id in
545  * @cguid: searched guid of ME client
546  * @client_id: id of host client to be set in file private structure
547  *
548  * returns ME client index
549  */
550 u8 mei_find_me_client_update_filext(struct mei_device *dev, struct mei_cl *priv,
551 				const uuid_le *cguid, u8 client_id)
552 {
553 	int i;
554 
555 	if (!dev || !priv || !cguid)
556 		return 0;
557 
558 	/* check for valid client id */
559 	i = mei_find_me_client_index(dev, *cguid);
560 	if (i >= 0) {
561 		priv->me_client_id = dev->me_clients[i].client_id;
562 		priv->state = MEI_FILE_CONNECTING;
563 		priv->host_client_id = client_id;
564 
565 		list_add_tail(&priv->link, &dev->file_list);
566 		return (u8)i;
567 	}
568 
569 	return 0;
570 }
571 
572 /**
573  * host_init_iamthif - mei initialization iamthif client.
574  *
575  * @dev: the device structure
576  *
577  */
578 void mei_host_init_iamthif(struct mei_device *dev)
579 {
580 	u8 i;
581 	unsigned char *msg_buf;
582 
583 	mei_cl_init(&dev->iamthif_cl, dev);
584 	dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
585 
586 	/* find ME amthi client */
587 	i = mei_find_me_client_update_filext(dev, &dev->iamthif_cl,
588 			    &mei_amthi_guid, MEI_IAMTHIF_HOST_CLIENT_ID);
589 	if (dev->iamthif_cl.state != MEI_FILE_CONNECTING) {
590 		dev_dbg(&dev->pdev->dev, "failed to find iamthif client.\n");
591 		return;
592 	}
593 
594 	/* Assign iamthif_mtu to the value received from ME  */
595 
596 	dev->iamthif_mtu = dev->me_clients[i].props.max_msg_length;
597 	dev_dbg(&dev->pdev->dev, "IAMTHIF_MTU = %d\n",
598 			dev->me_clients[i].props.max_msg_length);
599 
600 	kfree(dev->iamthif_msg_buf);
601 	dev->iamthif_msg_buf = NULL;
602 
603 	/* allocate storage for ME message buffer */
604 	msg_buf = kcalloc(dev->iamthif_mtu,
605 			sizeof(unsigned char), GFP_KERNEL);
606 	if (!msg_buf) {
607 		dev_dbg(&dev->pdev->dev, "memory allocation for ME message buffer failed.\n");
608 		return;
609 	}
610 
611 	dev->iamthif_msg_buf = msg_buf;
612 
613 	if (mei_connect(dev, &dev->iamthif_cl)) {
614 		dev_dbg(&dev->pdev->dev, "Failed to connect to AMTHI client\n");
615 		dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
616 		dev->iamthif_cl.host_client_id = 0;
617 	} else {
618 		dev->iamthif_cl.timer_count = CONNECT_TIMEOUT;
619 	}
620 }
621 
622 /**
623  * mei_alloc_file_private - allocates a private file structure and sets it up.
624  * @file: the file structure
625  *
626  * returns  The allocated file or NULL on failure
627  */
628 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
629 {
630 	struct mei_cl *cl;
631 
632 	cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
633 	if (!cl)
634 		return NULL;
635 
636 	mei_cl_init(cl, dev);
637 
638 	return cl;
639 }
640 
641 
642 
643 /**
644  * mei_disconnect_host_client - sends disconnect message to fw from host client.
645  *
646  * @dev: the device structure
647  * @cl: private data of the file object
648  *
649  * Locking: called under "dev->device_lock" lock
650  *
651  * returns 0 on success, <0 on failure.
652  */
653 int mei_disconnect_host_client(struct mei_device *dev, struct mei_cl *cl)
654 {
655 	int rets, err;
656 	long timeout = 15;	/* 15 seconds */
657 	struct mei_cl_cb *cb;
658 
659 	if (!dev || !cl)
660 		return -ENODEV;
661 
662 	if (cl->state != MEI_FILE_DISCONNECTING)
663 		return 0;
664 
665 	cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
666 	if (!cb)
667 		return -ENOMEM;
668 
669 	INIT_LIST_HEAD(&cb->cb_list);
670 	cb->file_private = cl;
671 	cb->major_file_operations = MEI_CLOSE;
672 	if (dev->mei_host_buffer_is_empty) {
673 		dev->mei_host_buffer_is_empty = false;
674 		if (mei_disconnect(dev, cl)) {
675 			rets = -ENODEV;
676 			dev_dbg(&dev->pdev->dev, "failed to call mei_disconnect.\n");
677 			goto free;
678 		}
679 		mdelay(10); /* Wait for hardware disconnection ready */
680 		list_add_tail(&cb->cb_list, &dev->ctrl_rd_list.mei_cb.cb_list);
681 	} else {
682 		dev_dbg(&dev->pdev->dev, "add disconnect cb to control write list\n");
683 		list_add_tail(&cb->cb_list,
684 				&dev->ctrl_wr_list.mei_cb.cb_list);
685 	}
686 	mutex_unlock(&dev->device_lock);
687 
688 	err = wait_event_timeout(dev->wait_recvd_msg,
689 		 (MEI_FILE_DISCONNECTED == cl->state),
690 		 timeout * HZ);
691 
692 	mutex_lock(&dev->device_lock);
693 	if (MEI_FILE_DISCONNECTED == cl->state) {
694 		rets = 0;
695 		dev_dbg(&dev->pdev->dev, "successfully disconnected from FW client.\n");
696 	} else {
697 		rets = -ENODEV;
698 		if (MEI_FILE_DISCONNECTED != cl->state)
699 			dev_dbg(&dev->pdev->dev, "wrong status client disconnect.\n");
700 
701 		if (err)
702 			dev_dbg(&dev->pdev->dev,
703 					"wait failed disconnect err=%08x\n",
704 					err);
705 
706 		dev_dbg(&dev->pdev->dev, "failed to disconnect from FW client.\n");
707 	}
708 
709 	mei_io_list_flush(&dev->ctrl_rd_list, cl);
710 	mei_io_list_flush(&dev->ctrl_wr_list, cl);
711 free:
712 	mei_free_cb_private(cb);
713 	return rets;
714 }
715 
716 /**
717  * mei_remove_client_from_file_list -
718  *	removes file private data from device file list
719  *
720  * @dev: the device structure
721  * @host_client_id: host client id to be removed
722  */
723 void mei_remove_client_from_file_list(struct mei_device *dev,
724 				       u8 host_client_id)
725 {
726 	struct mei_cl *cl_pos = NULL;
727 	struct mei_cl *cl_next = NULL;
728 	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
729 		if (host_client_id == cl_pos->host_client_id) {
730 			dev_dbg(&dev->pdev->dev, "remove host client = %d, ME client = %d\n",
731 					cl_pos->host_client_id,
732 					cl_pos->me_client_id);
733 			list_del_init(&cl_pos->link);
734 			break;
735 		}
736 	}
737 }
738