xref: /openbmc/linux/drivers/misc/mei/interrupt.c (revision 3b64b188)
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 
18 #include <linux/pci.h>
19 #include <linux/kthread.h>
20 #include <linux/interrupt.h>
21 #include <linux/fs.h>
22 #include <linux/jiffies.h>
23 
24 #include "mei_dev.h"
25 #include <linux/mei.h>
26 #include "hw.h"
27 #include "interface.h"
28 
29 
30 /**
31  * mei_interrupt_quick_handler - The ISR of the MEI device
32  *
33  * @irq: The irq number
34  * @dev_id: pointer to the device structure
35  *
36  * returns irqreturn_t
37  */
38 irqreturn_t mei_interrupt_quick_handler(int irq, void *dev_id)
39 {
40 	struct mei_device *dev = (struct mei_device *) dev_id;
41 	u32 csr_reg = mei_hcsr_read(dev);
42 
43 	if ((csr_reg & H_IS) != H_IS)
44 		return IRQ_NONE;
45 
46 	/* clear H_IS bit in H_CSR */
47 	mei_reg_write(dev, H_CSR, csr_reg);
48 
49 	return IRQ_WAKE_THREAD;
50 }
51 
52 /**
53  * _mei_cmpl - processes completed operation.
54  *
55  * @cl: private data of the file object.
56  * @cb_pos: callback block.
57  */
58 static void _mei_cmpl(struct mei_cl *cl, struct mei_cl_cb *cb_pos)
59 {
60 	if (cb_pos->major_file_operations == MEI_WRITE) {
61 		mei_free_cb_private(cb_pos);
62 		cb_pos = NULL;
63 		cl->writing_state = MEI_WRITE_COMPLETE;
64 		if (waitqueue_active(&cl->tx_wait))
65 			wake_up_interruptible(&cl->tx_wait);
66 
67 	} else if (cb_pos->major_file_operations == MEI_READ &&
68 			MEI_READING == cl->reading_state) {
69 		cl->reading_state = MEI_READ_COMPLETE;
70 		if (waitqueue_active(&cl->rx_wait))
71 			wake_up_interruptible(&cl->rx_wait);
72 
73 	}
74 }
75 
76 /**
77  * _mei_cmpl_iamthif - processes completed iamthif operation.
78  *
79  * @dev: the device structure.
80  * @cb_pos: callback block.
81  */
82 static void _mei_cmpl_iamthif(struct mei_device *dev, struct mei_cl_cb *cb_pos)
83 {
84 	if (dev->iamthif_canceled != 1) {
85 		dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
86 		dev->iamthif_stall_timer = 0;
87 		memcpy(cb_pos->response_buffer.data,
88 				dev->iamthif_msg_buf,
89 				dev->iamthif_msg_buf_index);
90 		list_add_tail(&cb_pos->cb_list,
91 				&dev->amthi_read_complete_list.mei_cb.cb_list);
92 		dev_dbg(&dev->pdev->dev, "amthi read completed.\n");
93 		dev->iamthif_timer = jiffies;
94 		dev_dbg(&dev->pdev->dev, "dev->iamthif_timer = %ld\n",
95 				dev->iamthif_timer);
96 	} else {
97 		mei_run_next_iamthif_cmd(dev);
98 	}
99 
100 	dev_dbg(&dev->pdev->dev, "completing amthi call back.\n");
101 	wake_up_interruptible(&dev->iamthif_cl.wait);
102 }
103 
104 
105 /**
106  * mei_irq_thread_read_amthi_message - bottom half read routine after ISR to
107  * handle the read amthi message data processing.
108  *
109  * @complete_list: An instance of our list structure
110  * @dev: the device structure
111  * @mei_hdr: header of amthi message
112  *
113  * returns 0 on success, <0 on failure.
114  */
115 static int mei_irq_thread_read_amthi_message(struct mei_io_list *complete_list,
116 		struct mei_device *dev,
117 		struct mei_msg_hdr *mei_hdr)
118 {
119 	struct mei_cl *cl;
120 	struct mei_cl_cb *cb;
121 	unsigned char *buffer;
122 
123 	BUG_ON(mei_hdr->me_addr != dev->iamthif_cl.me_client_id);
124 	BUG_ON(dev->iamthif_state != MEI_IAMTHIF_READING);
125 
126 	buffer = dev->iamthif_msg_buf + dev->iamthif_msg_buf_index;
127 	BUG_ON(dev->iamthif_mtu < dev->iamthif_msg_buf_index + mei_hdr->length);
128 
129 	mei_read_slots(dev, buffer, mei_hdr->length);
130 
131 	dev->iamthif_msg_buf_index += mei_hdr->length;
132 
133 	if (!mei_hdr->msg_complete)
134 		return 0;
135 
136 	dev_dbg(&dev->pdev->dev,
137 			"amthi_message_buffer_index =%d\n",
138 			mei_hdr->length);
139 
140 	dev_dbg(&dev->pdev->dev, "completed amthi read.\n ");
141 	if (!dev->iamthif_current_cb)
142 		return -ENODEV;
143 
144 	cb = dev->iamthif_current_cb;
145 	dev->iamthif_current_cb = NULL;
146 
147 	cl = (struct mei_cl *)cb->file_private;
148 	if (!cl)
149 		return -ENODEV;
150 
151 	dev->iamthif_stall_timer = 0;
152 	cb->information =	dev->iamthif_msg_buf_index;
153 	cb->read_time = jiffies;
154 	if (dev->iamthif_ioctl && cl == &dev->iamthif_cl) {
155 		/* found the iamthif cb */
156 		dev_dbg(&dev->pdev->dev, "complete the amthi read cb.\n ");
157 		dev_dbg(&dev->pdev->dev, "add the amthi read cb to complete.\n ");
158 		list_add_tail(&cb->cb_list,
159 						&complete_list->mei_cb.cb_list);
160 	}
161 	return 0;
162 }
163 
164 /**
165  * _mei_irq_thread_state_ok - checks if mei header matches file private data
166  *
167  * @cl: private data of the file object
168  * @mei_hdr: header of mei client message
169  *
170  * returns !=0 if matches, 0 if no match.
171  */
172 static int _mei_irq_thread_state_ok(struct mei_cl *cl,
173 				struct mei_msg_hdr *mei_hdr)
174 {
175 	return (cl->host_client_id == mei_hdr->host_addr &&
176 		cl->me_client_id == mei_hdr->me_addr &&
177 		cl->state == MEI_FILE_CONNECTED &&
178 		MEI_READ_COMPLETE != cl->reading_state);
179 }
180 
181 /**
182  * mei_irq_thread_read_client_message - bottom half read routine after ISR to
183  * handle the read mei client message data processing.
184  *
185  * @complete_list: An instance of our list structure
186  * @dev: the device structure
187  * @mei_hdr: header of mei client message
188  *
189  * returns 0 on success, <0 on failure.
190  */
191 static int mei_irq_thread_read_client_message(struct mei_io_list *complete_list,
192 		struct mei_device *dev,
193 		struct mei_msg_hdr *mei_hdr)
194 {
195 	struct mei_cl *cl;
196 	struct mei_cl_cb *cb_pos = NULL, *cb_next = NULL;
197 	unsigned char *buffer = NULL;
198 
199 	dev_dbg(&dev->pdev->dev, "start client msg\n");
200 	if (list_empty(&dev->read_list.mei_cb.cb_list))
201 		goto quit;
202 
203 	list_for_each_entry_safe(cb_pos, cb_next,
204 			&dev->read_list.mei_cb.cb_list, cb_list) {
205 		cl = (struct mei_cl *)cb_pos->file_private;
206 		if (cl && _mei_irq_thread_state_ok(cl, mei_hdr)) {
207 			cl->reading_state = MEI_READING;
208 			buffer = cb_pos->response_buffer.data + cb_pos->information;
209 
210 			if (cb_pos->response_buffer.size <
211 					mei_hdr->length + cb_pos->information) {
212 				dev_dbg(&dev->pdev->dev, "message overflow.\n");
213 				list_del(&cb_pos->cb_list);
214 				return -ENOMEM;
215 			}
216 			if (buffer)
217 				mei_read_slots(dev, buffer, mei_hdr->length);
218 
219 			cb_pos->information += mei_hdr->length;
220 			if (mei_hdr->msg_complete) {
221 				cl->status = 0;
222 				list_del(&cb_pos->cb_list);
223 				dev_dbg(&dev->pdev->dev,
224 					"completed read H cl = %d, ME cl = %d, length = %lu\n",
225 					cl->host_client_id,
226 					cl->me_client_id,
227 					cb_pos->information);
228 				list_add_tail(&cb_pos->cb_list,
229 					&complete_list->mei_cb.cb_list);
230 			}
231 
232 			break;
233 		}
234 
235 	}
236 
237 quit:
238 	dev_dbg(&dev->pdev->dev, "message read\n");
239 	if (!buffer) {
240 		mei_read_slots(dev, dev->rd_msg_buf, mei_hdr->length);
241 		dev_dbg(&dev->pdev->dev, "discarding message, header =%08x.\n",
242 				*(u32 *) dev->rd_msg_buf);
243 	}
244 
245 	return 0;
246 }
247 
248 /**
249  * _mei_irq_thread_iamthif_read - prepares to read iamthif data.
250  *
251  * @dev: the device structure.
252  * @slots: free slots.
253  *
254  * returns 0, OK; otherwise, error.
255  */
256 static int _mei_irq_thread_iamthif_read(struct mei_device *dev, s32 *slots)
257 {
258 
259 	if (((*slots) * sizeof(u32)) < (sizeof(struct mei_msg_hdr)
260 			+ sizeof(struct hbm_flow_control))) {
261 		return -EMSGSIZE;
262 	}
263 	*slots -= mei_data2slots(sizeof(struct hbm_flow_control));
264 	if (mei_send_flow_control(dev, &dev->iamthif_cl)) {
265 		dev_dbg(&dev->pdev->dev, "iamthif flow control failed\n");
266 		return -EIO;
267 	}
268 
269 	dev_dbg(&dev->pdev->dev, "iamthif flow control success\n");
270 	dev->iamthif_state = MEI_IAMTHIF_READING;
271 	dev->iamthif_flow_control_pending = false;
272 	dev->iamthif_msg_buf_index = 0;
273 	dev->iamthif_msg_buf_size = 0;
274 	dev->iamthif_stall_timer = IAMTHIF_STALL_TIMER;
275 	dev->mei_host_buffer_is_empty = mei_hbuf_is_empty(dev);
276 	return 0;
277 }
278 
279 /**
280  * _mei_irq_thread_close - processes close related operation.
281  *
282  * @dev: the device structure.
283  * @slots: free slots.
284  * @cb_pos: callback block.
285  * @cl: private data of the file object.
286  * @cmpl_list: complete list.
287  *
288  * returns 0, OK; otherwise, error.
289  */
290 static int _mei_irq_thread_close(struct mei_device *dev, s32 *slots,
291 				struct mei_cl_cb *cb_pos,
292 				struct mei_cl *cl,
293 				struct mei_io_list *cmpl_list)
294 {
295 	if ((*slots * sizeof(u32)) < (sizeof(struct mei_msg_hdr) +
296 			sizeof(struct hbm_client_disconnect_request)))
297 		return -EBADMSG;
298 
299 	*slots -= mei_data2slots(sizeof(struct hbm_client_disconnect_request));
300 
301 	if (mei_disconnect(dev, cl)) {
302 		cl->status = 0;
303 		cb_pos->information = 0;
304 		list_move_tail(&cb_pos->cb_list,
305 				&cmpl_list->mei_cb.cb_list);
306 		return -EMSGSIZE;
307 	} else {
308 		cl->state = MEI_FILE_DISCONNECTING;
309 		cl->status = 0;
310 		cb_pos->information = 0;
311 		list_move_tail(&cb_pos->cb_list,
312 				&dev->ctrl_rd_list.mei_cb.cb_list);
313 		cl->timer_count = MEI_CONNECT_TIMEOUT;
314 	}
315 
316 	return 0;
317 }
318 
319 /**
320  * is_treat_specially_client - checks if the message belongs
321  * to the file private data.
322  *
323  * @cl: private data of the file object
324  * @rs: connect response bus message
325  *
326  */
327 static bool is_treat_specially_client(struct mei_cl *cl,
328 		struct hbm_client_connect_response *rs)
329 {
330 
331 	if (cl->host_client_id == rs->host_addr &&
332 	    cl->me_client_id == rs->me_addr) {
333 		if (!rs->status) {
334 			cl->state = MEI_FILE_CONNECTED;
335 			cl->status = 0;
336 
337 		} else {
338 			cl->state = MEI_FILE_DISCONNECTED;
339 			cl->status = -ENODEV;
340 		}
341 		cl->timer_count = 0;
342 
343 		return true;
344 	}
345 	return false;
346 }
347 
348 /**
349  * mei_client_connect_response - connects to response irq routine
350  *
351  * @dev: the device structure
352  * @rs: connect response bus message
353  */
354 static void mei_client_connect_response(struct mei_device *dev,
355 		struct hbm_client_connect_response *rs)
356 {
357 
358 	struct mei_cl *cl;
359 	struct mei_cl_cb *cb_pos = NULL, *cb_next = NULL;
360 
361 	dev_dbg(&dev->pdev->dev,
362 			"connect_response:\n"
363 			"ME Client = %d\n"
364 			"Host Client = %d\n"
365 			"Status = %d\n",
366 			rs->me_addr,
367 			rs->host_addr,
368 			rs->status);
369 
370 	/* if WD or iamthif client treat specially */
371 
372 	if (is_treat_specially_client(&(dev->wd_cl), rs)) {
373 		dev_dbg(&dev->pdev->dev, "successfully connected to WD client.\n");
374 		mei_watchdog_register(dev);
375 
376 		/* next step in the state maching */
377 		mei_host_init_iamthif(dev);
378 		return;
379 	}
380 
381 	if (is_treat_specially_client(&(dev->iamthif_cl), rs)) {
382 		dev->iamthif_state = MEI_IAMTHIF_IDLE;
383 		return;
384 	}
385 	list_for_each_entry_safe(cb_pos, cb_next,
386 				&dev->ctrl_rd_list.mei_cb.cb_list, cb_list) {
387 
388 		cl = (struct mei_cl *)cb_pos->file_private;
389 		if (!cl) {
390 			list_del(&cb_pos->cb_list);
391 			return;
392 		}
393 		if (MEI_IOCTL == cb_pos->major_file_operations) {
394 			if (is_treat_specially_client(cl, rs)) {
395 				list_del(&cb_pos->cb_list);
396 				cl->status = 0;
397 				cl->timer_count = 0;
398 				break;
399 			}
400 		}
401 	}
402 }
403 
404 /**
405  * mei_client_disconnect_response - disconnects from response irq routine
406  *
407  * @dev: the device structure
408  * @rs: disconnect response bus message
409  */
410 static void mei_client_disconnect_response(struct mei_device *dev,
411 					struct hbm_client_connect_response *rs)
412 {
413 	struct mei_cl *cl;
414 	struct mei_cl_cb *cb_pos = NULL, *cb_next = NULL;
415 
416 	dev_dbg(&dev->pdev->dev,
417 			"disconnect_response:\n"
418 			"ME Client = %d\n"
419 			"Host Client = %d\n"
420 			"Status = %d\n",
421 			rs->me_addr,
422 			rs->host_addr,
423 			rs->status);
424 
425 	list_for_each_entry_safe(cb_pos, cb_next,
426 			&dev->ctrl_rd_list.mei_cb.cb_list, cb_list) {
427 		cl = (struct mei_cl *)cb_pos->file_private;
428 
429 		if (!cl) {
430 			list_del(&cb_pos->cb_list);
431 			return;
432 		}
433 
434 		dev_dbg(&dev->pdev->dev, "list_for_each_entry_safe in ctrl_rd_list.\n");
435 		if (cl->host_client_id == rs->host_addr &&
436 		    cl->me_client_id == rs->me_addr) {
437 
438 			list_del(&cb_pos->cb_list);
439 			if (!rs->status)
440 				cl->state = MEI_FILE_DISCONNECTED;
441 
442 			cl->status = 0;
443 			cl->timer_count = 0;
444 			break;
445 		}
446 	}
447 }
448 
449 /**
450  * same_flow_addr - tells if they have the same address.
451  *
452  * @file: private data of the file object.
453  * @flow: flow control.
454  *
455  * returns  !=0, same; 0,not.
456  */
457 static int same_flow_addr(struct mei_cl *cl, struct hbm_flow_control *flow)
458 {
459 	return (cl->host_client_id == flow->host_addr &&
460 		cl->me_client_id == flow->me_addr);
461 }
462 
463 /**
464  * add_single_flow_creds - adds single buffer credentials.
465  *
466  * @file: private data ot the file object.
467  * @flow: flow control.
468  */
469 static void add_single_flow_creds(struct mei_device *dev,
470 				  struct hbm_flow_control *flow)
471 {
472 	struct mei_me_client *client;
473 	int i;
474 
475 	for (i = 0; i < dev->me_clients_num; i++) {
476 		client = &dev->me_clients[i];
477 		if (client && flow->me_addr == client->client_id) {
478 			if (client->props.single_recv_buf) {
479 				client->mei_flow_ctrl_creds++;
480 				dev_dbg(&dev->pdev->dev, "recv flow ctrl msg ME %d (single).\n",
481 				    flow->me_addr);
482 				dev_dbg(&dev->pdev->dev, "flow control credentials =%d.\n",
483 				    client->mei_flow_ctrl_creds);
484 			} else {
485 				BUG();	/* error in flow control */
486 			}
487 		}
488 	}
489 }
490 
491 /**
492  * mei_client_flow_control_response - flow control response irq routine
493  *
494  * @dev: the device structure
495  * @flow_control: flow control response bus message
496  */
497 static void mei_client_flow_control_response(struct mei_device *dev,
498 		struct hbm_flow_control *flow_control)
499 {
500 	struct mei_cl *cl_pos = NULL;
501 	struct mei_cl *cl_next = NULL;
502 
503 	if (!flow_control->host_addr) {
504 		/* single receive buffer */
505 		add_single_flow_creds(dev, flow_control);
506 	} else {
507 		/* normal connection */
508 		list_for_each_entry_safe(cl_pos, cl_next,
509 				&dev->file_list, link) {
510 			dev_dbg(&dev->pdev->dev, "list_for_each_entry_safe in file_list\n");
511 
512 			dev_dbg(&dev->pdev->dev, "cl of host client %d ME client %d.\n",
513 			    cl_pos->host_client_id,
514 			    cl_pos->me_client_id);
515 			dev_dbg(&dev->pdev->dev, "flow ctrl msg for host %d ME %d.\n",
516 			    flow_control->host_addr,
517 			    flow_control->me_addr);
518 			if (same_flow_addr(cl_pos, flow_control)) {
519 				dev_dbg(&dev->pdev->dev, "recv ctrl msg for host  %d ME %d.\n",
520 				    flow_control->host_addr,
521 				    flow_control->me_addr);
522 				cl_pos->mei_flow_ctrl_creds++;
523 				dev_dbg(&dev->pdev->dev, "flow control credentials = %d.\n",
524 				    cl_pos->mei_flow_ctrl_creds);
525 				break;
526 			}
527 		}
528 	}
529 }
530 
531 /**
532  * same_disconn_addr - tells if they have the same address
533  *
534  * @file: private data of the file object.
535  * @disconn: disconnection request.
536  *
537  * returns !=0, same; 0,not.
538  */
539 static int same_disconn_addr(struct mei_cl *cl,
540 			     struct hbm_client_disconnect_request *disconn)
541 {
542 	return (cl->host_client_id == disconn->host_addr &&
543 		cl->me_client_id == disconn->me_addr);
544 }
545 
546 /**
547  * mei_client_disconnect_request - disconnects from request irq routine
548  *
549  * @dev: the device structure.
550  * @disconnect_req: disconnect request bus message.
551  */
552 static void mei_client_disconnect_request(struct mei_device *dev,
553 		struct hbm_client_disconnect_request *disconnect_req)
554 {
555 	struct mei_msg_hdr *mei_hdr;
556 	struct hbm_client_connect_response *disconnect_res;
557 	struct mei_cl *cl_pos = NULL;
558 	struct mei_cl *cl_next = NULL;
559 
560 	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
561 		if (same_disconn_addr(cl_pos, disconnect_req)) {
562 			dev_dbg(&dev->pdev->dev, "disconnect request host client %d ME client %d.\n",
563 					disconnect_req->host_addr,
564 					disconnect_req->me_addr);
565 			cl_pos->state = MEI_FILE_DISCONNECTED;
566 			cl_pos->timer_count = 0;
567 			if (cl_pos == &dev->wd_cl)
568 				dev->wd_pending = false;
569 			else if (cl_pos == &dev->iamthif_cl)
570 				dev->iamthif_timer = 0;
571 
572 			/* prepare disconnect response */
573 			mei_hdr =
574 				(struct mei_msg_hdr *) &dev->ext_msg_buf[0];
575 			mei_hdr->host_addr = 0;
576 			mei_hdr->me_addr = 0;
577 			mei_hdr->length =
578 				sizeof(struct hbm_client_connect_response);
579 			mei_hdr->msg_complete = 1;
580 			mei_hdr->reserved = 0;
581 
582 			disconnect_res =
583 				(struct hbm_client_connect_response *)
584 				&dev->ext_msg_buf[1];
585 			disconnect_res->host_addr = cl_pos->host_client_id;
586 			disconnect_res->me_addr = cl_pos->me_client_id;
587 			disconnect_res->hbm_cmd = CLIENT_DISCONNECT_RES_CMD;
588 			disconnect_res->status = 0;
589 			dev->extra_write_index = 2;
590 			break;
591 		}
592 	}
593 }
594 
595 
596 /**
597  * mei_irq_thread_read_bus_message - bottom half read routine after ISR to
598  * handle the read bus message cmd processing.
599  *
600  * @dev: the device structure
601  * @mei_hdr: header of bus message
602  */
603 static void mei_irq_thread_read_bus_message(struct mei_device *dev,
604 		struct mei_msg_hdr *mei_hdr)
605 {
606 	struct mei_bus_message *mei_msg;
607 	struct hbm_host_version_response *version_res;
608 	struct hbm_client_connect_response *connect_res;
609 	struct hbm_client_connect_response *disconnect_res;
610 	struct hbm_flow_control *flow_control;
611 	struct hbm_props_response *props_res;
612 	struct hbm_host_enum_response *enum_res;
613 	struct hbm_client_disconnect_request *disconnect_req;
614 	struct hbm_host_stop_request *host_stop_req;
615 	int res;
616 
617 
618 	/* read the message to our buffer */
619 	BUG_ON(mei_hdr->length >= sizeof(dev->rd_msg_buf));
620 	mei_read_slots(dev, dev->rd_msg_buf, mei_hdr->length);
621 	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
622 
623 	switch (mei_msg->hbm_cmd) {
624 	case HOST_START_RES_CMD:
625 		version_res = (struct hbm_host_version_response *) mei_msg;
626 		if (version_res->host_version_supported) {
627 			dev->version.major_version = HBM_MAJOR_VERSION;
628 			dev->version.minor_version = HBM_MINOR_VERSION;
629 			if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
630 			    dev->init_clients_state == MEI_START_MESSAGE) {
631 				dev->init_clients_timer = 0;
632 				mei_host_enum_clients_message(dev);
633 			} else {
634 				dev->recvd_msg = false;
635 				dev_dbg(&dev->pdev->dev, "IMEI reset due to received host start response bus message.\n");
636 				mei_reset(dev, 1);
637 				return;
638 			}
639 		} else {
640 			dev->version = version_res->me_max_version;
641 			/* send stop message */
642 			mei_hdr = (struct mei_msg_hdr *)&dev->wr_msg_buf[0];
643 			mei_hdr->host_addr = 0;
644 			mei_hdr->me_addr = 0;
645 			mei_hdr->length = sizeof(struct hbm_host_stop_request);
646 			mei_hdr->msg_complete = 1;
647 			mei_hdr->reserved = 0;
648 
649 			host_stop_req = (struct hbm_host_stop_request *)
650 							&dev->wr_msg_buf[1];
651 
652 			memset(host_stop_req,
653 					0,
654 					sizeof(struct hbm_host_stop_request));
655 			host_stop_req->hbm_cmd = HOST_STOP_REQ_CMD;
656 			host_stop_req->reason = DRIVER_STOP_REQUEST;
657 			mei_write_message(dev, mei_hdr,
658 					   (unsigned char *) (host_stop_req),
659 					   mei_hdr->length);
660 			dev_dbg(&dev->pdev->dev, "version mismatch.\n");
661 			return;
662 		}
663 
664 		dev->recvd_msg = true;
665 		dev_dbg(&dev->pdev->dev, "host start response message received.\n");
666 		break;
667 
668 	case CLIENT_CONNECT_RES_CMD:
669 		connect_res =
670 			(struct hbm_client_connect_response *) mei_msg;
671 		mei_client_connect_response(dev, connect_res);
672 		dev_dbg(&dev->pdev->dev, "client connect response message received.\n");
673 		wake_up(&dev->wait_recvd_msg);
674 		break;
675 
676 	case CLIENT_DISCONNECT_RES_CMD:
677 		disconnect_res =
678 			(struct hbm_client_connect_response *) mei_msg;
679 		mei_client_disconnect_response(dev, disconnect_res);
680 		dev_dbg(&dev->pdev->dev, "client disconnect response message received.\n");
681 		wake_up(&dev->wait_recvd_msg);
682 		break;
683 
684 	case MEI_FLOW_CONTROL_CMD:
685 		flow_control = (struct hbm_flow_control *) mei_msg;
686 		mei_client_flow_control_response(dev, flow_control);
687 		dev_dbg(&dev->pdev->dev, "client flow control response message received.\n");
688 		break;
689 
690 	case HOST_CLIENT_PROPERTIES_RES_CMD:
691 		props_res = (struct hbm_props_response *)mei_msg;
692 		if (props_res->status || !dev->me_clients) {
693 			dev_dbg(&dev->pdev->dev, "reset due to received host client properties response bus message wrong status.\n");
694 			mei_reset(dev, 1);
695 			return;
696 		}
697 		if (dev->me_clients[dev->me_client_presentation_num]
698 					.client_id == props_res->address) {
699 
700 			dev->me_clients[dev->me_client_presentation_num].props
701 						= props_res->client_properties;
702 
703 			if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
704 			    dev->init_clients_state ==
705 					MEI_CLIENT_PROPERTIES_MESSAGE) {
706 				dev->me_client_index++;
707 				dev->me_client_presentation_num++;
708 
709 				/** Send Client Properties request **/
710 				res = mei_host_client_properties(dev);
711 				if (res < 0) {
712 					dev_dbg(&dev->pdev->dev, "mei_host_client_properties() failed");
713 					return;
714 				} else if (!res) {
715 					/*
716 					 * No more clients to send to.
717 					 * Clear Map for indicating now ME clients
718 					 * with associated host client
719 					 */
720 					bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
721 					dev->open_handle_count = 0;
722 
723 					/*
724 					 * Reserving the first three client IDs
725 					 * Client Id 0 - Reserved for MEI Bus Message communications
726 					 * Client Id 1 - Reserved for Watchdog
727 					 * Client ID 2 - Reserved for AMTHI
728 					 */
729 					bitmap_set(dev->host_clients_map, 0, 3);
730 					dev->dev_state = MEI_DEV_ENABLED;
731 
732 					/* if wd initialization fails, initialization the AMTHI client,
733 					 * otherwise the AMTHI client will be initialized after the WD client connect response
734 					 * will be received
735 					 */
736 					if (mei_wd_host_init(dev))
737 						mei_host_init_iamthif(dev);
738 				}
739 
740 			} else {
741 				dev_dbg(&dev->pdev->dev, "reset due to received host client properties response bus message");
742 				mei_reset(dev, 1);
743 				return;
744 			}
745 		} else {
746 			dev_dbg(&dev->pdev->dev, "reset due to received host client properties response bus message for wrong client ID\n");
747 			mei_reset(dev, 1);
748 			return;
749 		}
750 		break;
751 
752 	case HOST_ENUM_RES_CMD:
753 		enum_res = (struct hbm_host_enum_response *) mei_msg;
754 		memcpy(dev->me_clients_map, enum_res->valid_addresses, 32);
755 		if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
756 		    dev->init_clients_state == MEI_ENUM_CLIENTS_MESSAGE) {
757 				dev->init_clients_timer = 0;
758 				dev->me_client_presentation_num = 0;
759 				dev->me_client_index = 0;
760 				mei_allocate_me_clients_storage(dev);
761 				dev->init_clients_state =
762 					MEI_CLIENT_PROPERTIES_MESSAGE;
763 				mei_host_client_properties(dev);
764 		} else {
765 			dev_dbg(&dev->pdev->dev, "reset due to received host enumeration clients response bus message.\n");
766 			mei_reset(dev, 1);
767 			return;
768 		}
769 		break;
770 
771 	case HOST_STOP_RES_CMD:
772 		dev->dev_state = MEI_DEV_DISABLED;
773 		dev_dbg(&dev->pdev->dev, "resetting because of FW stop response.\n");
774 		mei_reset(dev, 1);
775 		break;
776 
777 	case CLIENT_DISCONNECT_REQ_CMD:
778 		/* search for client */
779 		disconnect_req =
780 			(struct hbm_client_disconnect_request *) mei_msg;
781 		mei_client_disconnect_request(dev, disconnect_req);
782 		break;
783 
784 	case ME_STOP_REQ_CMD:
785 		/* prepare stop request */
786 		mei_hdr = (struct mei_msg_hdr *) &dev->ext_msg_buf[0];
787 		mei_hdr->host_addr = 0;
788 		mei_hdr->me_addr = 0;
789 		mei_hdr->length = sizeof(struct hbm_host_stop_request);
790 		mei_hdr->msg_complete = 1;
791 		mei_hdr->reserved = 0;
792 		host_stop_req =
793 			(struct hbm_host_stop_request *) &dev->ext_msg_buf[1];
794 		memset(host_stop_req, 0, sizeof(struct hbm_host_stop_request));
795 		host_stop_req->hbm_cmd = HOST_STOP_REQ_CMD;
796 		host_stop_req->reason = DRIVER_STOP_REQUEST;
797 		host_stop_req->reserved[0] = 0;
798 		host_stop_req->reserved[1] = 0;
799 		dev->extra_write_index = 2;
800 		break;
801 
802 	default:
803 		BUG();
804 		break;
805 
806 	}
807 }
808 
809 
810 /**
811  * _mei_hb_read - processes read related operation.
812  *
813  * @dev: the device structure.
814  * @slots: free slots.
815  * @cb_pos: callback block.
816  * @cl: private data of the file object.
817  * @cmpl_list: complete list.
818  *
819  * returns 0, OK; otherwise, error.
820  */
821 static int _mei_irq_thread_read(struct mei_device *dev,	s32 *slots,
822 			struct mei_cl_cb *cb_pos,
823 			struct mei_cl *cl,
824 			struct mei_io_list *cmpl_list)
825 {
826 	if ((*slots * sizeof(u32)) < (sizeof(struct mei_msg_hdr) +
827 			sizeof(struct hbm_flow_control))) {
828 		/* return the cancel routine */
829 		list_del(&cb_pos->cb_list);
830 		return -EBADMSG;
831 	}
832 
833 	*slots -= mei_data2slots(sizeof(struct hbm_flow_control));
834 
835 	if (mei_send_flow_control(dev, cl)) {
836 		cl->status = -ENODEV;
837 		cb_pos->information = 0;
838 		list_move_tail(&cb_pos->cb_list, &cmpl_list->mei_cb.cb_list);
839 		return -ENODEV;
840 	}
841 	list_move_tail(&cb_pos->cb_list, &dev->read_list.mei_cb.cb_list);
842 
843 	return 0;
844 }
845 
846 
847 /**
848  * _mei_irq_thread_ioctl - processes ioctl related operation.
849  *
850  * @dev: the device structure.
851  * @slots: free slots.
852  * @cb_pos: callback block.
853  * @cl: private data of the file object.
854  * @cmpl_list: complete list.
855  *
856  * returns 0, OK; otherwise, error.
857  */
858 static int _mei_irq_thread_ioctl(struct mei_device *dev, s32 *slots,
859 			struct mei_cl_cb *cb_pos,
860 			struct mei_cl *cl,
861 			struct mei_io_list *cmpl_list)
862 {
863 	if ((*slots * sizeof(u32)) < (sizeof(struct mei_msg_hdr) +
864 			sizeof(struct hbm_client_connect_request))) {
865 		/* return the cancel routine */
866 		list_del(&cb_pos->cb_list);
867 		return -EBADMSG;
868 	}
869 
870 	cl->state = MEI_FILE_CONNECTING;
871 	 *slots -= mei_data2slots(sizeof(struct hbm_client_connect_request));
872 	if (mei_connect(dev, cl)) {
873 		cl->status = -ENODEV;
874 		cb_pos->information = 0;
875 		list_del(&cb_pos->cb_list);
876 		return -ENODEV;
877 	} else {
878 		list_move_tail(&cb_pos->cb_list,
879 			&dev->ctrl_rd_list.mei_cb.cb_list);
880 		cl->timer_count = MEI_CONNECT_TIMEOUT;
881 	}
882 	return 0;
883 }
884 
885 /**
886  * _mei_irq_thread_cmpl - processes completed and no-iamthif operation.
887  *
888  * @dev: the device structure.
889  * @slots: free slots.
890  * @cb_pos: callback block.
891  * @cl: private data of the file object.
892  * @cmpl_list: complete list.
893  *
894  * returns 0, OK; otherwise, error.
895  */
896 static int _mei_irq_thread_cmpl(struct mei_device *dev,	s32 *slots,
897 			struct mei_cl_cb *cb_pos,
898 			struct mei_cl *cl,
899 			struct mei_io_list *cmpl_list)
900 {
901 	struct mei_msg_hdr *mei_hdr;
902 
903 	if ((*slots * sizeof(u32)) >= (sizeof(struct mei_msg_hdr) +
904 			(cb_pos->request_buffer.size -
905 			cb_pos->information))) {
906 		mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
907 		mei_hdr->host_addr = cl->host_client_id;
908 		mei_hdr->me_addr = cl->me_client_id;
909 		mei_hdr->length = cb_pos->request_buffer.size -
910 					cb_pos->information;
911 		mei_hdr->msg_complete = 1;
912 		mei_hdr->reserved = 0;
913 		dev_dbg(&dev->pdev->dev, "cb_pos->request_buffer.size =%d"
914 			"mei_hdr->msg_complete = %d\n",
915 				cb_pos->request_buffer.size,
916 				mei_hdr->msg_complete);
917 		dev_dbg(&dev->pdev->dev, "cb_pos->information  =%lu\n",
918 				cb_pos->information);
919 		dev_dbg(&dev->pdev->dev, "mei_hdr->length  =%d\n",
920 				mei_hdr->length);
921 		*slots -= mei_data2slots(mei_hdr->length);
922 		if (mei_write_message(dev, mei_hdr,
923 				(unsigned char *)
924 				(cb_pos->request_buffer.data +
925 				cb_pos->information),
926 				mei_hdr->length)) {
927 			cl->status = -ENODEV;
928 			list_move_tail(&cb_pos->cb_list,
929 				&cmpl_list->mei_cb.cb_list);
930 			return -ENODEV;
931 		} else {
932 			if (mei_flow_ctrl_reduce(dev, cl))
933 				return -ENODEV;
934 			cl->status = 0;
935 			cb_pos->information += mei_hdr->length;
936 			list_move_tail(&cb_pos->cb_list,
937 				&dev->write_waiting_list.mei_cb.cb_list);
938 		}
939 	} else if (*slots == dev->hbuf_depth) {
940 		/* buffer is still empty */
941 		mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
942 		mei_hdr->host_addr = cl->host_client_id;
943 		mei_hdr->me_addr = cl->me_client_id;
944 		mei_hdr->length =
945 			(*slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
946 		mei_hdr->msg_complete = 0;
947 		mei_hdr->reserved = 0;
948 		*slots -= mei_data2slots(mei_hdr->length);
949 		if (mei_write_message(dev, mei_hdr,
950 					(unsigned char *)
951 					(cb_pos->request_buffer.data +
952 					cb_pos->information),
953 					mei_hdr->length)) {
954 			cl->status = -ENODEV;
955 			list_move_tail(&cb_pos->cb_list,
956 				&cmpl_list->mei_cb.cb_list);
957 			return -ENODEV;
958 		} else {
959 			cb_pos->information += mei_hdr->length;
960 			dev_dbg(&dev->pdev->dev,
961 					"cb_pos->request_buffer.size =%d"
962 					" mei_hdr->msg_complete = %d\n",
963 					cb_pos->request_buffer.size,
964 					mei_hdr->msg_complete);
965 			dev_dbg(&dev->pdev->dev, "cb_pos->information  =%lu\n",
966 					cb_pos->information);
967 			dev_dbg(&dev->pdev->dev, "mei_hdr->length  =%d\n",
968 					mei_hdr->length);
969 		}
970 		return -EMSGSIZE;
971 	} else {
972 		return -EBADMSG;
973 	}
974 
975 	return 0;
976 }
977 
978 /**
979  * _mei_irq_thread_cmpl_iamthif - processes completed iamthif operation.
980  *
981  * @dev: the device structure.
982  * @slots: free slots.
983  * @cb_pos: callback block.
984  * @cl: private data of the file object.
985  * @cmpl_list: complete list.
986  *
987  * returns 0, OK; otherwise, error.
988  */
989 static int _mei_irq_thread_cmpl_iamthif(struct mei_device *dev, s32 *slots,
990 			struct mei_cl_cb *cb_pos,
991 			struct mei_cl *cl,
992 			struct mei_io_list *cmpl_list)
993 {
994 	struct mei_msg_hdr *mei_hdr;
995 
996 	if ((*slots * sizeof(u32)) >= (sizeof(struct mei_msg_hdr) +
997 			dev->iamthif_msg_buf_size -
998 			dev->iamthif_msg_buf_index)) {
999 		mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
1000 		mei_hdr->host_addr = cl->host_client_id;
1001 		mei_hdr->me_addr = cl->me_client_id;
1002 		mei_hdr->length = dev->iamthif_msg_buf_size -
1003 			dev->iamthif_msg_buf_index;
1004 		mei_hdr->msg_complete = 1;
1005 		mei_hdr->reserved = 0;
1006 
1007 		*slots -= mei_data2slots(mei_hdr->length);
1008 
1009 		if (mei_write_message(dev, mei_hdr,
1010 					(dev->iamthif_msg_buf +
1011 					dev->iamthif_msg_buf_index),
1012 					mei_hdr->length)) {
1013 			dev->iamthif_state = MEI_IAMTHIF_IDLE;
1014 			cl->status = -ENODEV;
1015 			list_del(&cb_pos->cb_list);
1016 			return -ENODEV;
1017 		} else {
1018 			if (mei_flow_ctrl_reduce(dev, cl))
1019 				return -ENODEV;
1020 			dev->iamthif_msg_buf_index += mei_hdr->length;
1021 			cb_pos->information = dev->iamthif_msg_buf_index;
1022 			cl->status = 0;
1023 			dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
1024 			dev->iamthif_flow_control_pending = true;
1025 			/* save iamthif cb sent to amthi client */
1026 			dev->iamthif_current_cb = cb_pos;
1027 			list_move_tail(&cb_pos->cb_list,
1028 				&dev->write_waiting_list.mei_cb.cb_list);
1029 
1030 		}
1031 	} else if (*slots == dev->hbuf_depth) {
1032 		/* buffer is still empty */
1033 		mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
1034 		mei_hdr->host_addr = cl->host_client_id;
1035 		mei_hdr->me_addr = cl->me_client_id;
1036 		mei_hdr->length =
1037 			(*slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
1038 		mei_hdr->msg_complete = 0;
1039 		mei_hdr->reserved = 0;
1040 
1041 		*slots -= mei_data2slots(mei_hdr->length);
1042 
1043 		if (mei_write_message(dev, mei_hdr,
1044 					(dev->iamthif_msg_buf +
1045 					dev->iamthif_msg_buf_index),
1046 					mei_hdr->length)) {
1047 			cl->status = -ENODEV;
1048 			list_del(&cb_pos->cb_list);
1049 		} else {
1050 			dev->iamthif_msg_buf_index += mei_hdr->length;
1051 		}
1052 		return -EMSGSIZE;
1053 	} else {
1054 		return -EBADMSG;
1055 	}
1056 
1057 	return 0;
1058 }
1059 
1060 /**
1061  * mei_irq_thread_read_handler - bottom half read routine after ISR to
1062  * handle the read processing.
1063  *
1064  * @cmpl_list: An instance of our list structure
1065  * @dev: the device structure
1066  * @slots: slots to read.
1067  *
1068  * returns 0 on success, <0 on failure.
1069  */
1070 static int mei_irq_thread_read_handler(struct mei_io_list *cmpl_list,
1071 		struct mei_device *dev,
1072 		s32 *slots)
1073 {
1074 	struct mei_msg_hdr *mei_hdr;
1075 	struct mei_cl *cl_pos = NULL;
1076 	struct mei_cl *cl_next = NULL;
1077 	int ret = 0;
1078 
1079 	if (!dev->rd_msg_hdr) {
1080 		dev->rd_msg_hdr = mei_mecbrw_read(dev);
1081 		dev_dbg(&dev->pdev->dev, "slots =%08x.\n", *slots);
1082 		(*slots)--;
1083 		dev_dbg(&dev->pdev->dev, "slots =%08x.\n", *slots);
1084 	}
1085 	mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
1086 	dev_dbg(&dev->pdev->dev, "mei_hdr->length =%d\n", mei_hdr->length);
1087 
1088 	if (mei_hdr->reserved || !dev->rd_msg_hdr) {
1089 		dev_dbg(&dev->pdev->dev, "corrupted message header.\n");
1090 		ret = -EBADMSG;
1091 		goto end;
1092 	}
1093 
1094 	if (mei_hdr->host_addr || mei_hdr->me_addr) {
1095 		list_for_each_entry_safe(cl_pos, cl_next,
1096 					&dev->file_list, link) {
1097 			dev_dbg(&dev->pdev->dev,
1098 					"list_for_each_entry_safe read host"
1099 					" client = %d, ME client = %d\n",
1100 					cl_pos->host_client_id,
1101 					cl_pos->me_client_id);
1102 			if (cl_pos->host_client_id == mei_hdr->host_addr &&
1103 			    cl_pos->me_client_id == mei_hdr->me_addr)
1104 				break;
1105 		}
1106 
1107 		if (&cl_pos->link == &dev->file_list) {
1108 			dev_dbg(&dev->pdev->dev, "corrupted message header\n");
1109 			ret = -EBADMSG;
1110 			goto end;
1111 		}
1112 	}
1113 	if (((*slots) * sizeof(u32)) < mei_hdr->length) {
1114 		dev_dbg(&dev->pdev->dev,
1115 				"we can't read the message slots =%08x.\n",
1116 				*slots);
1117 		/* we can't read the message */
1118 		ret = -ERANGE;
1119 		goto end;
1120 	}
1121 
1122 	/* decide where to read the message too */
1123 	if (!mei_hdr->host_addr) {
1124 		dev_dbg(&dev->pdev->dev, "call mei_irq_thread_read_bus_message.\n");
1125 		mei_irq_thread_read_bus_message(dev, mei_hdr);
1126 		dev_dbg(&dev->pdev->dev, "end mei_irq_thread_read_bus_message.\n");
1127 	} else if (mei_hdr->host_addr == dev->iamthif_cl.host_client_id &&
1128 		   (MEI_FILE_CONNECTED == dev->iamthif_cl.state) &&
1129 		   (dev->iamthif_state == MEI_IAMTHIF_READING)) {
1130 		dev_dbg(&dev->pdev->dev, "call mei_irq_thread_read_iamthif_message.\n");
1131 		dev_dbg(&dev->pdev->dev, "mei_hdr->length =%d\n",
1132 				mei_hdr->length);
1133 		ret = mei_irq_thread_read_amthi_message(cmpl_list,
1134 							dev, mei_hdr);
1135 		if (ret)
1136 			goto end;
1137 
1138 	} else {
1139 		dev_dbg(&dev->pdev->dev, "call mei_irq_thread_read_client_message.\n");
1140 		ret = mei_irq_thread_read_client_message(cmpl_list,
1141 							 dev, mei_hdr);
1142 		if (ret)
1143 			goto end;
1144 
1145 	}
1146 
1147 	/* reset the number of slots and header */
1148 	*slots = mei_count_full_read_slots(dev);
1149 	dev->rd_msg_hdr = 0;
1150 
1151 	if (*slots == -EOVERFLOW) {
1152 		/* overflow - reset */
1153 		dev_dbg(&dev->pdev->dev, "resetting due to slots overflow.\n");
1154 		/* set the event since message has been read */
1155 		ret = -ERANGE;
1156 		goto end;
1157 	}
1158 end:
1159 	return ret;
1160 }
1161 
1162 
1163 /**
1164  * mei_irq_thread_write_handler - bottom half write routine after
1165  * ISR to handle the write processing.
1166  *
1167  * @cmpl_list: An instance of our list structure
1168  * @dev: the device structure
1169  * @slots: slots to write.
1170  *
1171  * returns 0 on success, <0 on failure.
1172  */
1173 static int mei_irq_thread_write_handler(struct mei_io_list *cmpl_list,
1174 		struct mei_device *dev,
1175 		s32 *slots)
1176 {
1177 
1178 	struct mei_cl *cl;
1179 	struct mei_cl_cb *pos = NULL, *next = NULL;
1180 	struct mei_io_list *list;
1181 	int ret;
1182 
1183 	if (!mei_hbuf_is_empty(dev)) {
1184 		dev_dbg(&dev->pdev->dev, "host buffer is not empty.\n");
1185 		return 0;
1186 	}
1187 	*slots = mei_hbuf_empty_slots(dev);
1188 	if (*slots <= 0)
1189 		return -EMSGSIZE;
1190 
1191 	/* complete all waiting for write CB */
1192 	dev_dbg(&dev->pdev->dev, "complete all waiting for write cb.\n");
1193 
1194 	list = &dev->write_waiting_list;
1195 	list_for_each_entry_safe(pos, next, &list->mei_cb.cb_list, cb_list) {
1196 		cl = (struct mei_cl *)pos->file_private;
1197 		if (cl == NULL)
1198 			continue;
1199 
1200 		cl->status = 0;
1201 		list_del(&pos->cb_list);
1202 		if (MEI_WRITING == cl->writing_state &&
1203 		   (pos->major_file_operations == MEI_WRITE) &&
1204 		   (cl != &dev->iamthif_cl)) {
1205 			dev_dbg(&dev->pdev->dev, "MEI WRITE COMPLETE\n");
1206 			cl->writing_state = MEI_WRITE_COMPLETE;
1207 			list_add_tail(&pos->cb_list,
1208 				      &cmpl_list->mei_cb.cb_list);
1209 		}
1210 		if (cl == &dev->iamthif_cl) {
1211 			dev_dbg(&dev->pdev->dev, "check iamthif flow control.\n");
1212 			if (dev->iamthif_flow_control_pending) {
1213 				ret = _mei_irq_thread_iamthif_read(dev, slots);
1214 				if (ret)
1215 					return ret;
1216 			}
1217 		}
1218 	}
1219 
1220 	if (dev->wd_state == MEI_WD_STOPPING) {
1221 		dev->wd_state = MEI_WD_IDLE;
1222 		wake_up_interruptible(&dev->wait_stop_wd);
1223 	}
1224 
1225 	if (dev->extra_write_index) {
1226 		dev_dbg(&dev->pdev->dev, "extra_write_index =%d.\n",
1227 				dev->extra_write_index);
1228 		mei_write_message(dev,
1229 				(struct mei_msg_hdr *) &dev->ext_msg_buf[0],
1230 				(unsigned char *) &dev->ext_msg_buf[1],
1231 				(dev->extra_write_index - 1) * sizeof(u32));
1232 		*slots -= dev->extra_write_index;
1233 		dev->extra_write_index = 0;
1234 	}
1235 	if (dev->dev_state == MEI_DEV_ENABLED) {
1236 		if (dev->wd_pending &&
1237 		    mei_flow_ctrl_creds(dev, &dev->wd_cl) > 0) {
1238 			if (mei_wd_send(dev))
1239 				dev_dbg(&dev->pdev->dev, "wd send failed.\n");
1240 			else if (mei_flow_ctrl_reduce(dev, &dev->wd_cl))
1241 				return -ENODEV;
1242 
1243 			dev->wd_pending = false;
1244 
1245 			if (dev->wd_state == MEI_WD_RUNNING)
1246 				*slots -= mei_data2slots(MEI_WD_START_MSG_SIZE);
1247 			else
1248 				*slots -= mei_data2slots(MEI_WD_STOP_MSG_SIZE);
1249 		}
1250 	}
1251 
1252 	/* complete control write list CB */
1253 	dev_dbg(&dev->pdev->dev, "complete control write list cb.\n");
1254 	list_for_each_entry_safe(pos, next,
1255 				&dev->ctrl_wr_list.mei_cb.cb_list, cb_list) {
1256 		cl = (struct mei_cl *) pos->file_private;
1257 		if (!cl) {
1258 			list_del(&pos->cb_list);
1259 			return -ENODEV;
1260 		}
1261 		switch (pos->major_file_operations) {
1262 		case MEI_CLOSE:
1263 			/* send disconnect message */
1264 			ret = _mei_irq_thread_close(dev, slots, pos, cl, cmpl_list);
1265 			if (ret)
1266 				return ret;
1267 
1268 			break;
1269 		case MEI_READ:
1270 			/* send flow control message */
1271 			ret = _mei_irq_thread_read(dev, slots, pos, cl, cmpl_list);
1272 			if (ret)
1273 				return ret;
1274 
1275 			break;
1276 		case MEI_IOCTL:
1277 			/* connect message */
1278 			if (mei_other_client_is_connecting(dev, cl))
1279 				continue;
1280 			ret = _mei_irq_thread_ioctl(dev, slots, pos, cl, cmpl_list);
1281 			if (ret)
1282 				return ret;
1283 
1284 			break;
1285 
1286 		default:
1287 			BUG();
1288 		}
1289 
1290 	}
1291 	/* complete  write list CB */
1292 	dev_dbg(&dev->pdev->dev, "complete write list cb.\n");
1293 	list_for_each_entry_safe(pos, next,
1294 				&dev->write_list.mei_cb.cb_list, cb_list) {
1295 		cl = (struct mei_cl *)pos->file_private;
1296 		if (cl == NULL)
1297 			continue;
1298 
1299 		if (cl != &dev->iamthif_cl) {
1300 			if (mei_flow_ctrl_creds(dev, cl) <= 0) {
1301 				dev_dbg(&dev->pdev->dev,
1302 					"No flow control credentials for client %d, not sending.\n",
1303 					cl->host_client_id);
1304 				continue;
1305 			}
1306 			ret = _mei_irq_thread_cmpl(dev, slots, pos,
1307 						cl, cmpl_list);
1308 			if (ret)
1309 				return ret;
1310 
1311 		} else if (cl == &dev->iamthif_cl) {
1312 			/* IAMTHIF IOCTL */
1313 			dev_dbg(&dev->pdev->dev, "complete amthi write cb.\n");
1314 			if (mei_flow_ctrl_creds(dev, cl) <= 0) {
1315 				dev_dbg(&dev->pdev->dev,
1316 					"No flow control credentials for amthi client %d.\n",
1317 					cl->host_client_id);
1318 				continue;
1319 			}
1320 			ret = _mei_irq_thread_cmpl_iamthif(dev, slots, pos,
1321 						cl, cmpl_list);
1322 			if (ret)
1323 				return ret;
1324 
1325 		}
1326 
1327 	}
1328 	return 0;
1329 }
1330 
1331 
1332 
1333 /**
1334  * mei_timer - timer function.
1335  *
1336  * @work: pointer to the work_struct structure
1337  *
1338  * NOTE: This function is called by timer interrupt work
1339  */
1340 void mei_timer(struct work_struct *work)
1341 {
1342 	unsigned long timeout;
1343 	struct mei_cl *cl_pos = NULL;
1344 	struct mei_cl *cl_next = NULL;
1345 	struct list_head *amthi_complete_list = NULL;
1346 	struct mei_cl_cb  *cb_pos = NULL;
1347 	struct mei_cl_cb  *cb_next = NULL;
1348 
1349 	struct mei_device *dev = container_of(work,
1350 					struct mei_device, timer_work.work);
1351 
1352 
1353 	mutex_lock(&dev->device_lock);
1354 	if (dev->dev_state != MEI_DEV_ENABLED) {
1355 		if (dev->dev_state == MEI_DEV_INIT_CLIENTS) {
1356 			if (dev->init_clients_timer) {
1357 				if (--dev->init_clients_timer == 0) {
1358 					dev_dbg(&dev->pdev->dev, "IMEI reset due to init clients timeout ,init clients state = %d.\n",
1359 						dev->init_clients_state);
1360 					mei_reset(dev, 1);
1361 				}
1362 			}
1363 		}
1364 		goto out;
1365 	}
1366 	/*** connect/disconnect timeouts ***/
1367 	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
1368 		if (cl_pos->timer_count) {
1369 			if (--cl_pos->timer_count == 0) {
1370 				dev_dbg(&dev->pdev->dev, "HECI reset due to connect/disconnect timeout.\n");
1371 				mei_reset(dev, 1);
1372 				goto out;
1373 			}
1374 		}
1375 	}
1376 
1377 	if (dev->iamthif_stall_timer) {
1378 		if (--dev->iamthif_stall_timer == 0) {
1379 			dev_dbg(&dev->pdev->dev, "resetting because of hang to amthi.\n");
1380 			mei_reset(dev, 1);
1381 			dev->iamthif_msg_buf_size = 0;
1382 			dev->iamthif_msg_buf_index = 0;
1383 			dev->iamthif_canceled = false;
1384 			dev->iamthif_ioctl = true;
1385 			dev->iamthif_state = MEI_IAMTHIF_IDLE;
1386 			dev->iamthif_timer = 0;
1387 
1388 			if (dev->iamthif_current_cb)
1389 				mei_free_cb_private(dev->iamthif_current_cb);
1390 
1391 			dev->iamthif_file_object = NULL;
1392 			dev->iamthif_current_cb = NULL;
1393 			mei_run_next_iamthif_cmd(dev);
1394 		}
1395 	}
1396 
1397 	if (dev->iamthif_timer) {
1398 
1399 		timeout = dev->iamthif_timer +
1400 				msecs_to_jiffies(IAMTHIF_READ_TIMER);
1401 
1402 		dev_dbg(&dev->pdev->dev, "dev->iamthif_timer = %ld\n",
1403 				dev->iamthif_timer);
1404 		dev_dbg(&dev->pdev->dev, "timeout = %ld\n", timeout);
1405 		dev_dbg(&dev->pdev->dev, "jiffies = %ld\n", jiffies);
1406 		if (time_after(jiffies, timeout)) {
1407 			/*
1408 			 * User didn't read the AMTHI data on time (15sec)
1409 			 * freeing AMTHI for other requests
1410 			 */
1411 
1412 			dev_dbg(&dev->pdev->dev, "freeing AMTHI for other requests\n");
1413 
1414 			amthi_complete_list = &dev->amthi_read_complete_list.
1415 					mei_cb.cb_list;
1416 
1417 			list_for_each_entry_safe(cb_pos, cb_next, amthi_complete_list, cb_list) {
1418 
1419 				cl_pos = cb_pos->file_object->private_data;
1420 
1421 				/* Finding the AMTHI entry. */
1422 				if (cl_pos == &dev->iamthif_cl)
1423 					list_del(&cb_pos->cb_list);
1424 			}
1425 			if (dev->iamthif_current_cb)
1426 				mei_free_cb_private(dev->iamthif_current_cb);
1427 
1428 			dev->iamthif_file_object->private_data = NULL;
1429 			dev->iamthif_file_object = NULL;
1430 			dev->iamthif_current_cb = NULL;
1431 			dev->iamthif_timer = 0;
1432 			mei_run_next_iamthif_cmd(dev);
1433 
1434 		}
1435 	}
1436 out:
1437 	schedule_delayed_work(&dev->timer_work, 2 * HZ);
1438 	mutex_unlock(&dev->device_lock);
1439 }
1440 
1441 /**
1442  *  mei_interrupt_thread_handler - function called after ISR to handle the interrupt
1443  * processing.
1444  *
1445  * @irq: The irq number
1446  * @dev_id: pointer to the device structure
1447  *
1448  * returns irqreturn_t
1449  *
1450  */
1451 irqreturn_t mei_interrupt_thread_handler(int irq, void *dev_id)
1452 {
1453 	struct mei_device *dev = (struct mei_device *) dev_id;
1454 	struct mei_io_list complete_list;
1455 	struct mei_cl_cb *cb_pos = NULL, *cb_next = NULL;
1456 	struct mei_cl *cl;
1457 	s32 slots;
1458 	int rets;
1459 	bool  bus_message_received;
1460 
1461 
1462 	dev_dbg(&dev->pdev->dev, "function called after ISR to handle the interrupt processing.\n");
1463 	/* initialize our complete list */
1464 	mutex_lock(&dev->device_lock);
1465 	mei_io_list_init(&complete_list);
1466 	dev->host_hw_state = mei_hcsr_read(dev);
1467 
1468 	/* Ack the interrupt here
1469 	 * In case of MSI we don't go through the quick handler */
1470 	if (pci_dev_msi_enabled(dev->pdev))
1471 		mei_reg_write(dev, H_CSR, dev->host_hw_state);
1472 
1473 	dev->me_hw_state = mei_mecsr_read(dev);
1474 
1475 	/* check if ME wants a reset */
1476 	if ((dev->me_hw_state & ME_RDY_HRA) == 0 &&
1477 	    dev->dev_state != MEI_DEV_RESETING &&
1478 	    dev->dev_state != MEI_DEV_INITIALIZING) {
1479 		dev_dbg(&dev->pdev->dev, "FW not ready.\n");
1480 		mei_reset(dev, 1);
1481 		mutex_unlock(&dev->device_lock);
1482 		return IRQ_HANDLED;
1483 	}
1484 
1485 	/*  check if we need to start the dev */
1486 	if ((dev->host_hw_state & H_RDY) == 0) {
1487 		if ((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA) {
1488 			dev_dbg(&dev->pdev->dev, "we need to start the dev.\n");
1489 			dev->host_hw_state |= (H_IE | H_IG | H_RDY);
1490 			mei_hcsr_set(dev);
1491 			dev->dev_state = MEI_DEV_INIT_CLIENTS;
1492 			dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
1493 			/* link is established
1494 			 * start sending messages.
1495 			 */
1496 			mei_host_start_message(dev);
1497 			mutex_unlock(&dev->device_lock);
1498 			return IRQ_HANDLED;
1499 		} else {
1500 			dev_dbg(&dev->pdev->dev, "FW not ready.\n");
1501 			mutex_unlock(&dev->device_lock);
1502 			return IRQ_HANDLED;
1503 		}
1504 	}
1505 	/* check slots available for reading */
1506 	slots = mei_count_full_read_slots(dev);
1507 	dev_dbg(&dev->pdev->dev, "slots =%08x  extra_write_index =%08x.\n",
1508 		slots, dev->extra_write_index);
1509 	while (slots > 0 && !dev->extra_write_index) {
1510 		dev_dbg(&dev->pdev->dev, "slots =%08x  extra_write_index =%08x.\n",
1511 				slots, dev->extra_write_index);
1512 		dev_dbg(&dev->pdev->dev, "call mei_irq_thread_read_handler.\n");
1513 		rets = mei_irq_thread_read_handler(&complete_list, dev, &slots);
1514 		if (rets)
1515 			goto end;
1516 	}
1517 	rets = mei_irq_thread_write_handler(&complete_list, dev, &slots);
1518 end:
1519 	dev_dbg(&dev->pdev->dev, "end of bottom half function.\n");
1520 	dev->host_hw_state = mei_hcsr_read(dev);
1521 	dev->mei_host_buffer_is_empty = mei_hbuf_is_empty(dev);
1522 
1523 	bus_message_received = false;
1524 	if (dev->recvd_msg && waitqueue_active(&dev->wait_recvd_msg)) {
1525 		dev_dbg(&dev->pdev->dev, "received waiting bus message\n");
1526 		bus_message_received = true;
1527 	}
1528 	mutex_unlock(&dev->device_lock);
1529 	if (bus_message_received) {
1530 		dev_dbg(&dev->pdev->dev, "wake up dev->wait_recvd_msg\n");
1531 		wake_up_interruptible(&dev->wait_recvd_msg);
1532 		bus_message_received = false;
1533 	}
1534 	if (list_empty(&complete_list.mei_cb.cb_list))
1535 		return IRQ_HANDLED;
1536 
1537 
1538 	list_for_each_entry_safe(cb_pos, cb_next,
1539 			&complete_list.mei_cb.cb_list, cb_list) {
1540 		cl = (struct mei_cl *)cb_pos->file_private;
1541 		list_del(&cb_pos->cb_list);
1542 		if (cl) {
1543 			if (cl != &dev->iamthif_cl) {
1544 				dev_dbg(&dev->pdev->dev, "completing call back.\n");
1545 				_mei_cmpl(cl, cb_pos);
1546 				cb_pos = NULL;
1547 			} else if (cl == &dev->iamthif_cl) {
1548 				_mei_cmpl_iamthif(dev, cb_pos);
1549 			}
1550 		}
1551 	}
1552 	return IRQ_HANDLED;
1553 }
1554