Commit | Line | Data |
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2e62c498 | 1 | // SPDX-License-Identifier: GPL-2.0 |
222818c3 TW |
2 | /* |
3 | * Intel Management Engine Interface (Intel MEI) Linux driver | |
4 | * Copyright (c) 2015, Intel Corporation. | |
222818c3 TW |
5 | */ |
6 | ||
7 | #include <linux/module.h> | |
8 | #include <linux/slab.h> | |
9 | #include <linux/interrupt.h> | |
c9cf20ee | 10 | #include <linux/debugfs.h> |
7a23f80e | 11 | #include <linux/completion.h> |
222818c3 TW |
12 | #include <linux/watchdog.h> |
13 | ||
14 | #include <linux/uuid.h> | |
15 | #include <linux/mei_cl_bus.h> | |
16 | ||
17 | /* | |
18 | * iAMT Watchdog Device | |
19 | */ | |
20 | #define INTEL_AMT_WATCHDOG_ID "iamt_wdt" | |
21 | ||
22 | #define MEI_WDT_DEFAULT_TIMEOUT 120 /* seconds */ | |
23 | #define MEI_WDT_MIN_TIMEOUT 120 /* seconds */ | |
24 | #define MEI_WDT_MAX_TIMEOUT 65535 /* seconds */ | |
25 | ||
26 | /* Commands */ | |
27 | #define MEI_MANAGEMENT_CONTROL 0x02 | |
28 | ||
29 | /* MEI Management Control version number */ | |
30 | #define MEI_MC_VERSION_NUMBER 0x10 | |
31 | ||
32 | /* Sub Commands */ | |
33 | #define MEI_MC_START_WD_TIMER_REQ 0x13 | |
7a23f80e TW |
34 | #define MEI_MC_START_WD_TIMER_RES 0x83 |
35 | #define MEI_WDT_STATUS_SUCCESS 0 | |
36 | #define MEI_WDT_WDSTATE_NOT_REQUIRED 0x1 | |
222818c3 TW |
37 | #define MEI_MC_STOP_WD_TIMER_REQ 0x14 |
38 | ||
39 | /** | |
40 | * enum mei_wdt_state - internal watchdog state | |
41 | * | |
7a23f80e | 42 | * @MEI_WDT_PROBE: wd in probing stage |
222818c3 TW |
43 | * @MEI_WDT_IDLE: wd is idle and not opened |
44 | * @MEI_WDT_START: wd was opened, start was called | |
45 | * @MEI_WDT_RUNNING: wd is expecting keep alive pings | |
46 | * @MEI_WDT_STOPPING: wd is stopping and will move to IDLE | |
7a23f80e | 47 | * @MEI_WDT_NOT_REQUIRED: wd device is not required |
222818c3 TW |
48 | */ |
49 | enum mei_wdt_state { | |
7a23f80e | 50 | MEI_WDT_PROBE, |
222818c3 TW |
51 | MEI_WDT_IDLE, |
52 | MEI_WDT_START, | |
53 | MEI_WDT_RUNNING, | |
54 | MEI_WDT_STOPPING, | |
7a23f80e | 55 | MEI_WDT_NOT_REQUIRED, |
222818c3 TW |
56 | }; |
57 | ||
c9cf20ee TW |
58 | static const char *mei_wdt_state_str(enum mei_wdt_state state) |
59 | { | |
60 | switch (state) { | |
7a23f80e TW |
61 | case MEI_WDT_PROBE: |
62 | return "PROBE"; | |
c9cf20ee TW |
63 | case MEI_WDT_IDLE: |
64 | return "IDLE"; | |
65 | case MEI_WDT_START: | |
66 | return "START"; | |
67 | case MEI_WDT_RUNNING: | |
68 | return "RUNNING"; | |
69 | case MEI_WDT_STOPPING: | |
70 | return "STOPPING"; | |
7a23f80e TW |
71 | case MEI_WDT_NOT_REQUIRED: |
72 | return "NOT_REQUIRED"; | |
c9cf20ee TW |
73 | default: |
74 | return "unknown"; | |
75 | } | |
76 | } | |
c9cf20ee | 77 | |
222818c3 TW |
78 | /** |
79 | * struct mei_wdt - mei watchdog driver | |
80 | * @wdd: watchdog device | |
81 | * | |
82 | * @cldev: mei watchdog client device | |
83 | * @state: watchdog internal state | |
7a23f80e TW |
84 | * @resp_required: ping required response |
85 | * @response: ping response completion | |
86 | * @unregister: unregister worker | |
87 | * @reg_lock: watchdog device registration lock | |
222818c3 | 88 | * @timeout: watchdog current timeout |
c9cf20ee TW |
89 | * |
90 | * @dbgfs_dir: debugfs dir entry | |
222818c3 TW |
91 | */ |
92 | struct mei_wdt { | |
93 | struct watchdog_device wdd; | |
94 | ||
95 | struct mei_cl_device *cldev; | |
96 | enum mei_wdt_state state; | |
7a23f80e TW |
97 | bool resp_required; |
98 | struct completion response; | |
99 | struct work_struct unregister; | |
100 | struct mutex reg_lock; | |
222818c3 | 101 | u16 timeout; |
c9cf20ee TW |
102 | |
103 | #if IS_ENABLED(CONFIG_DEBUG_FS) | |
104 | struct dentry *dbgfs_dir; | |
105 | #endif /* CONFIG_DEBUG_FS */ | |
222818c3 TW |
106 | }; |
107 | ||
108 | /* | |
109 | * struct mei_mc_hdr - Management Control Command Header | |
110 | * | |
111 | * @command: Management Control (0x2) | |
112 | * @bytecount: Number of bytes in the message beyond this byte | |
113 | * @subcommand: Management Control Subcommand | |
114 | * @versionnumber: Management Control Version (0x10) | |
115 | */ | |
116 | struct mei_mc_hdr { | |
117 | u8 command; | |
118 | u8 bytecount; | |
119 | u8 subcommand; | |
120 | u8 versionnumber; | |
121 | }; | |
122 | ||
123 | /** | |
124 | * struct mei_wdt_start_request watchdog start/ping | |
125 | * | |
126 | * @hdr: Management Control Command Header | |
127 | * @timeout: timeout value | |
128 | * @reserved: reserved (legacy) | |
129 | */ | |
130 | struct mei_wdt_start_request { | |
131 | struct mei_mc_hdr hdr; | |
132 | u16 timeout; | |
133 | u8 reserved[17]; | |
134 | } __packed; | |
135 | ||
7a23f80e TW |
136 | /** |
137 | * struct mei_wdt_start_response watchdog start/ping response | |
138 | * | |
139 | * @hdr: Management Control Command Header | |
140 | * @status: operation status | |
141 | * @wdstate: watchdog status bit mask | |
142 | */ | |
143 | struct mei_wdt_start_response { | |
144 | struct mei_mc_hdr hdr; | |
145 | u8 status; | |
146 | u8 wdstate; | |
147 | } __packed; | |
148 | ||
222818c3 TW |
149 | /** |
150 | * struct mei_wdt_stop_request - watchdog stop | |
151 | * | |
152 | * @hdr: Management Control Command Header | |
153 | */ | |
154 | struct mei_wdt_stop_request { | |
155 | struct mei_mc_hdr hdr; | |
156 | } __packed; | |
157 | ||
158 | /** | |
159 | * mei_wdt_ping - send wd start/ping command | |
160 | * | |
161 | * @wdt: mei watchdog device | |
162 | * | |
163 | * Return: 0 on success, | |
164 | * negative errno code on failure | |
165 | */ | |
166 | static int mei_wdt_ping(struct mei_wdt *wdt) | |
167 | { | |
168 | struct mei_wdt_start_request req; | |
169 | const size_t req_len = sizeof(req); | |
170 | int ret; | |
171 | ||
172 | memset(&req, 0, req_len); | |
173 | req.hdr.command = MEI_MANAGEMENT_CONTROL; | |
174 | req.hdr.bytecount = req_len - offsetof(struct mei_mc_hdr, subcommand); | |
175 | req.hdr.subcommand = MEI_MC_START_WD_TIMER_REQ; | |
176 | req.hdr.versionnumber = MEI_MC_VERSION_NUMBER; | |
177 | req.timeout = wdt->timeout; | |
178 | ||
179 | ret = mei_cldev_send(wdt->cldev, (u8 *)&req, req_len); | |
180 | if (ret < 0) | |
181 | return ret; | |
182 | ||
183 | return 0; | |
184 | } | |
185 | ||
186 | /** | |
187 | * mei_wdt_stop - send wd stop command | |
188 | * | |
189 | * @wdt: mei watchdog device | |
190 | * | |
191 | * Return: 0 on success, | |
192 | * negative errno code on failure | |
193 | */ | |
194 | static int mei_wdt_stop(struct mei_wdt *wdt) | |
195 | { | |
196 | struct mei_wdt_stop_request req; | |
197 | const size_t req_len = sizeof(req); | |
198 | int ret; | |
199 | ||
200 | memset(&req, 0, req_len); | |
201 | req.hdr.command = MEI_MANAGEMENT_CONTROL; | |
202 | req.hdr.bytecount = req_len - offsetof(struct mei_mc_hdr, subcommand); | |
203 | req.hdr.subcommand = MEI_MC_STOP_WD_TIMER_REQ; | |
204 | req.hdr.versionnumber = MEI_MC_VERSION_NUMBER; | |
205 | ||
206 | ret = mei_cldev_send(wdt->cldev, (u8 *)&req, req_len); | |
207 | if (ret < 0) | |
208 | return ret; | |
209 | ||
210 | return 0; | |
211 | } | |
212 | ||
213 | /** | |
214 | * mei_wdt_ops_start - wd start command from the watchdog core. | |
215 | * | |
216 | * @wdd: watchdog device | |
217 | * | |
218 | * Return: 0 on success or -ENODEV; | |
219 | */ | |
220 | static int mei_wdt_ops_start(struct watchdog_device *wdd) | |
221 | { | |
222 | struct mei_wdt *wdt = watchdog_get_drvdata(wdd); | |
223 | ||
224 | wdt->state = MEI_WDT_START; | |
225 | wdd->timeout = wdt->timeout; | |
226 | return 0; | |
227 | } | |
228 | ||
229 | /** | |
230 | * mei_wdt_ops_stop - wd stop command from the watchdog core. | |
231 | * | |
232 | * @wdd: watchdog device | |
233 | * | |
234 | * Return: 0 if success, negative errno code for failure | |
235 | */ | |
236 | static int mei_wdt_ops_stop(struct watchdog_device *wdd) | |
237 | { | |
238 | struct mei_wdt *wdt = watchdog_get_drvdata(wdd); | |
239 | int ret; | |
240 | ||
241 | if (wdt->state != MEI_WDT_RUNNING) | |
242 | return 0; | |
243 | ||
244 | wdt->state = MEI_WDT_STOPPING; | |
245 | ||
246 | ret = mei_wdt_stop(wdt); | |
247 | if (ret) | |
248 | return ret; | |
249 | ||
250 | wdt->state = MEI_WDT_IDLE; | |
251 | ||
252 | return 0; | |
253 | } | |
254 | ||
255 | /** | |
256 | * mei_wdt_ops_ping - wd ping command from the watchdog core. | |
257 | * | |
258 | * @wdd: watchdog device | |
259 | * | |
260 | * Return: 0 if success, negative errno code on failure | |
261 | */ | |
262 | static int mei_wdt_ops_ping(struct watchdog_device *wdd) | |
263 | { | |
264 | struct mei_wdt *wdt = watchdog_get_drvdata(wdd); | |
265 | int ret; | |
266 | ||
267 | if (wdt->state != MEI_WDT_START && wdt->state != MEI_WDT_RUNNING) | |
268 | return 0; | |
269 | ||
7a23f80e TW |
270 | if (wdt->resp_required) |
271 | init_completion(&wdt->response); | |
272 | ||
273 | wdt->state = MEI_WDT_RUNNING; | |
222818c3 TW |
274 | ret = mei_wdt_ping(wdt); |
275 | if (ret) | |
276 | return ret; | |
277 | ||
7a23f80e TW |
278 | if (wdt->resp_required) |
279 | ret = wait_for_completion_killable(&wdt->response); | |
222818c3 | 280 | |
7a23f80e | 281 | return ret; |
222818c3 TW |
282 | } |
283 | ||
284 | /** | |
285 | * mei_wdt_ops_set_timeout - wd set timeout command from the watchdog core. | |
286 | * | |
287 | * @wdd: watchdog device | |
288 | * @timeout: timeout value to set | |
289 | * | |
290 | * Return: 0 if success, negative errno code for failure | |
291 | */ | |
292 | static int mei_wdt_ops_set_timeout(struct watchdog_device *wdd, | |
293 | unsigned int timeout) | |
294 | { | |
295 | ||
296 | struct mei_wdt *wdt = watchdog_get_drvdata(wdd); | |
297 | ||
298 | /* valid value is already checked by the caller */ | |
299 | wdt->timeout = timeout; | |
300 | wdd->timeout = timeout; | |
301 | ||
302 | return 0; | |
303 | } | |
304 | ||
305 | static const struct watchdog_ops wd_ops = { | |
306 | .owner = THIS_MODULE, | |
307 | .start = mei_wdt_ops_start, | |
308 | .stop = mei_wdt_ops_stop, | |
309 | .ping = mei_wdt_ops_ping, | |
310 | .set_timeout = mei_wdt_ops_set_timeout, | |
311 | }; | |
312 | ||
313 | /* not const as the firmware_version field need to be retrieved */ | |
314 | static struct watchdog_info wd_info = { | |
315 | .identity = INTEL_AMT_WATCHDOG_ID, | |
316 | .options = WDIOF_KEEPALIVEPING | | |
317 | WDIOF_SETTIMEOUT | | |
318 | WDIOF_ALARMONLY, | |
319 | }; | |
320 | ||
7a23f80e TW |
321 | /** |
322 | * __mei_wdt_is_registered - check if wdt is registered | |
323 | * | |
324 | * @wdt: mei watchdog device | |
325 | * | |
326 | * Return: true if the wdt is registered with the watchdog subsystem | |
327 | * Locking: should be called under wdt->reg_lock | |
328 | */ | |
329 | static inline bool __mei_wdt_is_registered(struct mei_wdt *wdt) | |
330 | { | |
331 | return !!watchdog_get_drvdata(&wdt->wdd); | |
332 | } | |
333 | ||
222818c3 TW |
334 | /** |
335 | * mei_wdt_unregister - unregister from the watchdog subsystem | |
336 | * | |
337 | * @wdt: mei watchdog device | |
338 | */ | |
339 | static void mei_wdt_unregister(struct mei_wdt *wdt) | |
340 | { | |
7a23f80e TW |
341 | mutex_lock(&wdt->reg_lock); |
342 | ||
343 | if (__mei_wdt_is_registered(wdt)) { | |
344 | watchdog_unregister_device(&wdt->wdd); | |
345 | watchdog_set_drvdata(&wdt->wdd, NULL); | |
346 | memset(&wdt->wdd, 0, sizeof(wdt->wdd)); | |
347 | } | |
348 | ||
349 | mutex_unlock(&wdt->reg_lock); | |
222818c3 TW |
350 | } |
351 | ||
352 | /** | |
353 | * mei_wdt_register - register with the watchdog subsystem | |
354 | * | |
355 | * @wdt: mei watchdog device | |
356 | * | |
357 | * Return: 0 if success, negative errno code for failure | |
358 | */ | |
359 | static int mei_wdt_register(struct mei_wdt *wdt) | |
360 | { | |
361 | struct device *dev; | |
362 | int ret; | |
363 | ||
364 | if (!wdt || !wdt->cldev) | |
365 | return -EINVAL; | |
366 | ||
367 | dev = &wdt->cldev->dev; | |
368 | ||
7a23f80e TW |
369 | mutex_lock(&wdt->reg_lock); |
370 | ||
371 | if (__mei_wdt_is_registered(wdt)) { | |
372 | ret = 0; | |
373 | goto out; | |
374 | } | |
375 | ||
222818c3 TW |
376 | wdt->wdd.info = &wd_info; |
377 | wdt->wdd.ops = &wd_ops; | |
378 | wdt->wdd.parent = dev; | |
379 | wdt->wdd.timeout = MEI_WDT_DEFAULT_TIMEOUT; | |
380 | wdt->wdd.min_timeout = MEI_WDT_MIN_TIMEOUT; | |
381 | wdt->wdd.max_timeout = MEI_WDT_MAX_TIMEOUT; | |
382 | ||
383 | watchdog_set_drvdata(&wdt->wdd, wdt); | |
9eff1140 AU |
384 | watchdog_stop_on_reboot(&wdt->wdd); |
385 | ||
222818c3 | 386 | ret = watchdog_register_device(&wdt->wdd); |
2b7ebd34 | 387 | if (ret) |
222818c3 | 388 | watchdog_set_drvdata(&wdt->wdd, NULL); |
222818c3 | 389 | |
7a23f80e TW |
390 | wdt->state = MEI_WDT_IDLE; |
391 | ||
392 | out: | |
393 | mutex_unlock(&wdt->reg_lock); | |
222818c3 TW |
394 | return ret; |
395 | } | |
396 | ||
7a23f80e TW |
397 | static void mei_wdt_unregister_work(struct work_struct *work) |
398 | { | |
399 | struct mei_wdt *wdt = container_of(work, struct mei_wdt, unregister); | |
400 | ||
401 | mei_wdt_unregister(wdt); | |
402 | } | |
403 | ||
404 | /** | |
7c7a6077 | 405 | * mei_wdt_rx - callback for data receive |
7a23f80e TW |
406 | * |
407 | * @cldev: bus device | |
408 | */ | |
7c7a6077 | 409 | static void mei_wdt_rx(struct mei_cl_device *cldev) |
7a23f80e TW |
410 | { |
411 | struct mei_wdt *wdt = mei_cldev_get_drvdata(cldev); | |
412 | struct mei_wdt_start_response res; | |
413 | const size_t res_len = sizeof(res); | |
414 | int ret; | |
415 | ||
416 | ret = mei_cldev_recv(wdt->cldev, (u8 *)&res, res_len); | |
417 | if (ret < 0) { | |
418 | dev_err(&cldev->dev, "failure in recv %d\n", ret); | |
419 | return; | |
420 | } | |
421 | ||
422 | /* Empty response can be sent on stop */ | |
423 | if (ret == 0) | |
424 | return; | |
425 | ||
426 | if (ret < sizeof(struct mei_mc_hdr)) { | |
427 | dev_err(&cldev->dev, "recv small data %d\n", ret); | |
428 | return; | |
429 | } | |
430 | ||
431 | if (res.hdr.command != MEI_MANAGEMENT_CONTROL || | |
432 | res.hdr.versionnumber != MEI_MC_VERSION_NUMBER) { | |
433 | dev_err(&cldev->dev, "wrong command received\n"); | |
434 | return; | |
435 | } | |
436 | ||
437 | if (res.hdr.subcommand != MEI_MC_START_WD_TIMER_RES) { | |
438 | dev_warn(&cldev->dev, "unsupported command %d :%s[%d]\n", | |
439 | res.hdr.subcommand, | |
440 | mei_wdt_state_str(wdt->state), | |
441 | wdt->state); | |
442 | return; | |
443 | } | |
444 | ||
445 | /* Run the unregistration in a worker as this can be | |
446 | * run only after ping completion, otherwise the flow will | |
447 | * deadlock on watchdog core mutex. | |
448 | */ | |
449 | if (wdt->state == MEI_WDT_RUNNING) { | |
450 | if (res.wdstate & MEI_WDT_WDSTATE_NOT_REQUIRED) { | |
451 | wdt->state = MEI_WDT_NOT_REQUIRED; | |
452 | schedule_work(&wdt->unregister); | |
453 | } | |
454 | goto out; | |
455 | } | |
456 | ||
457 | if (wdt->state == MEI_WDT_PROBE) { | |
458 | if (res.wdstate & MEI_WDT_WDSTATE_NOT_REQUIRED) { | |
459 | wdt->state = MEI_WDT_NOT_REQUIRED; | |
460 | } else { | |
461 | /* stop the watchdog and register watchdog device */ | |
462 | mei_wdt_stop(wdt); | |
463 | mei_wdt_register(wdt); | |
464 | } | |
465 | return; | |
466 | } | |
467 | ||
468 | dev_warn(&cldev->dev, "not in correct state %s[%d]\n", | |
469 | mei_wdt_state_str(wdt->state), wdt->state); | |
470 | ||
471 | out: | |
472 | if (!completion_done(&wdt->response)) | |
473 | complete(&wdt->response); | |
474 | } | |
475 | ||
3a20a5c3 | 476 | /* |
7c7a6077 | 477 | * mei_wdt_notif - callback for event notification |
3a20a5c3 TW |
478 | * |
479 | * @cldev: bus device | |
480 | */ | |
7c7a6077 | 481 | static void mei_wdt_notif(struct mei_cl_device *cldev) |
3a20a5c3 TW |
482 | { |
483 | struct mei_wdt *wdt = mei_cldev_get_drvdata(cldev); | |
484 | ||
485 | if (wdt->state != MEI_WDT_NOT_REQUIRED) | |
486 | return; | |
487 | ||
488 | mei_wdt_register(wdt); | |
489 | } | |
490 | ||
c9cf20ee TW |
491 | #if IS_ENABLED(CONFIG_DEBUG_FS) |
492 | ||
ad1cd720 TW |
493 | static ssize_t mei_dbgfs_read_activation(struct file *file, char __user *ubuf, |
494 | size_t cnt, loff_t *ppos) | |
495 | { | |
496 | struct mei_wdt *wdt = file->private_data; | |
497 | const size_t bufsz = 32; | |
498 | char buf[32]; | |
499 | ssize_t pos; | |
500 | ||
501 | mutex_lock(&wdt->reg_lock); | |
502 | pos = scnprintf(buf, bufsz, "%s\n", | |
503 | __mei_wdt_is_registered(wdt) ? "activated" : "deactivated"); | |
504 | mutex_unlock(&wdt->reg_lock); | |
505 | ||
506 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, pos); | |
507 | } | |
508 | ||
509 | static const struct file_operations dbgfs_fops_activation = { | |
510 | .open = simple_open, | |
511 | .read = mei_dbgfs_read_activation, | |
512 | .llseek = generic_file_llseek, | |
513 | }; | |
514 | ||
c9cf20ee TW |
515 | static ssize_t mei_dbgfs_read_state(struct file *file, char __user *ubuf, |
516 | size_t cnt, loff_t *ppos) | |
517 | { | |
518 | struct mei_wdt *wdt = file->private_data; | |
7692a982 | 519 | char buf[32]; |
c9cf20ee TW |
520 | ssize_t pos; |
521 | ||
7692a982 TW |
522 | pos = scnprintf(buf, sizeof(buf), "state: %s\n", |
523 | mei_wdt_state_str(wdt->state)); | |
c9cf20ee TW |
524 | |
525 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, pos); | |
526 | } | |
527 | ||
528 | static const struct file_operations dbgfs_fops_state = { | |
529 | .open = simple_open, | |
530 | .read = mei_dbgfs_read_state, | |
531 | .llseek = generic_file_llseek, | |
532 | }; | |
533 | ||
534 | static void dbgfs_unregister(struct mei_wdt *wdt) | |
535 | { | |
536 | debugfs_remove_recursive(wdt->dbgfs_dir); | |
537 | wdt->dbgfs_dir = NULL; | |
538 | } | |
539 | ||
64079cf9 | 540 | static void dbgfs_register(struct mei_wdt *wdt) |
c9cf20ee | 541 | { |
64079cf9 | 542 | struct dentry *dir; |
c9cf20ee TW |
543 | |
544 | dir = debugfs_create_dir(KBUILD_MODNAME, NULL); | |
c9cf20ee | 545 | wdt->dbgfs_dir = dir; |
c9cf20ee | 546 | |
64079cf9 | 547 | debugfs_create_file("state", S_IRUSR, dir, wdt, &dbgfs_fops_state); |
ad1cd720 | 548 | |
64079cf9 GKH |
549 | debugfs_create_file("activation", S_IRUSR, dir, wdt, |
550 | &dbgfs_fops_activation); | |
c9cf20ee TW |
551 | } |
552 | ||
553 | #else | |
554 | ||
555 | static inline void dbgfs_unregister(struct mei_wdt *wdt) {} | |
64079cf9 | 556 | static inline void dbgfs_register(struct mei_wdt *wdt) {} |
c9cf20ee TW |
557 | #endif /* CONFIG_DEBUG_FS */ |
558 | ||
222818c3 TW |
559 | static int mei_wdt_probe(struct mei_cl_device *cldev, |
560 | const struct mei_cl_device_id *id) | |
561 | { | |
562 | struct mei_wdt *wdt; | |
563 | int ret; | |
564 | ||
565 | wdt = kzalloc(sizeof(struct mei_wdt), GFP_KERNEL); | |
566 | if (!wdt) | |
567 | return -ENOMEM; | |
568 | ||
569 | wdt->timeout = MEI_WDT_DEFAULT_TIMEOUT; | |
7a23f80e | 570 | wdt->state = MEI_WDT_PROBE; |
222818c3 | 571 | wdt->cldev = cldev; |
7a23f80e TW |
572 | wdt->resp_required = mei_cldev_ver(cldev) > 0x1; |
573 | mutex_init(&wdt->reg_lock); | |
574 | init_completion(&wdt->response); | |
575 | INIT_WORK(&wdt->unregister, mei_wdt_unregister_work); | |
576 | ||
222818c3 TW |
577 | mei_cldev_set_drvdata(cldev, wdt); |
578 | ||
579 | ret = mei_cldev_enable(cldev); | |
580 | if (ret < 0) { | |
581 | dev_err(&cldev->dev, "Could not enable cl device\n"); | |
582 | goto err_out; | |
583 | } | |
584 | ||
7c7a6077 AU |
585 | ret = mei_cldev_register_rx_cb(wdt->cldev, mei_wdt_rx); |
586 | if (ret) { | |
587 | dev_err(&cldev->dev, "Could not reg rx event ret=%d\n", ret); | |
588 | goto err_disable; | |
589 | } | |
3a20a5c3 | 590 | |
7c7a6077 | 591 | ret = mei_cldev_register_notif_cb(wdt->cldev, mei_wdt_notif); |
3a20a5c3 | 592 | /* on legacy devices notification is not supported |
3a20a5c3 TW |
593 | */ |
594 | if (ret && ret != -EOPNOTSUPP) { | |
7c7a6077 | 595 | dev_err(&cldev->dev, "Could not reg notif event ret=%d\n", ret); |
7a23f80e TW |
596 | goto err_disable; |
597 | } | |
598 | ||
222818c3 TW |
599 | wd_info.firmware_version = mei_cldev_ver(cldev); |
600 | ||
7a23f80e TW |
601 | if (wdt->resp_required) |
602 | ret = mei_wdt_ping(wdt); | |
603 | else | |
604 | ret = mei_wdt_register(wdt); | |
605 | ||
222818c3 TW |
606 | if (ret) |
607 | goto err_disable; | |
608 | ||
64079cf9 | 609 | dbgfs_register(wdt); |
c9cf20ee | 610 | |
222818c3 TW |
611 | return 0; |
612 | ||
613 | err_disable: | |
614 | mei_cldev_disable(cldev); | |
615 | ||
616 | err_out: | |
617 | kfree(wdt); | |
618 | ||
619 | return ret; | |
620 | } | |
621 | ||
622 | static int mei_wdt_remove(struct mei_cl_device *cldev) | |
623 | { | |
624 | struct mei_wdt *wdt = mei_cldev_get_drvdata(cldev); | |
625 | ||
7a23f80e TW |
626 | /* Free the caller in case of fw initiated or unexpected reset */ |
627 | if (!completion_done(&wdt->response)) | |
628 | complete(&wdt->response); | |
629 | ||
630 | cancel_work_sync(&wdt->unregister); | |
631 | ||
222818c3 TW |
632 | mei_wdt_unregister(wdt); |
633 | ||
634 | mei_cldev_disable(cldev); | |
635 | ||
c9cf20ee TW |
636 | dbgfs_unregister(wdt); |
637 | ||
222818c3 TW |
638 | kfree(wdt); |
639 | ||
640 | return 0; | |
641 | } | |
642 | ||
643 | #define MEI_UUID_WD UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, \ | |
644 | 0x89, 0x9D, 0xA9, 0x15, 0x14, 0xCB, 0x32, 0xAB) | |
645 | ||
4cb30b04 | 646 | static const struct mei_cl_device_id mei_wdt_tbl[] = { |
7a23f80e | 647 | { .uuid = MEI_UUID_WD, .version = MEI_CL_VERSION_ANY }, |
222818c3 TW |
648 | /* required last entry */ |
649 | { } | |
650 | }; | |
651 | MODULE_DEVICE_TABLE(mei, mei_wdt_tbl); | |
652 | ||
653 | static struct mei_cl_driver mei_wdt_driver = { | |
654 | .id_table = mei_wdt_tbl, | |
655 | .name = KBUILD_MODNAME, | |
656 | ||
657 | .probe = mei_wdt_probe, | |
658 | .remove = mei_wdt_remove, | |
659 | }; | |
660 | ||
b2a2f708 | 661 | module_mei_cl_driver(mei_wdt_driver); |
222818c3 TW |
662 | |
663 | MODULE_AUTHOR("Intel Corporation"); | |
2e62c498 | 664 | MODULE_LICENSE("GPL v2"); |
222818c3 | 665 | MODULE_DESCRIPTION("Device driver for Intel MEI iAMT watchdog"); |