Commit | Line | Data |
---|---|---|
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 | ||
4700df05 | 108 | /** |
222818c3 TW |
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 | /** | |
4700df05 | 124 | * struct mei_wdt_start_request - watchdog start/ping |
222818c3 TW |
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 | 136 | /** |
4700df05 | 137 | * struct mei_wdt_start_response - watchdog start/ping response |
7a23f80e TW |
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 | 384 | watchdog_stop_on_reboot(&wdt->wdd); |
740c0a57 | 385 | watchdog_stop_on_unregister(&wdt->wdd); |
9eff1140 | 386 | |
222818c3 | 387 | ret = watchdog_register_device(&wdt->wdd); |
2b7ebd34 | 388 | if (ret) |
222818c3 | 389 | watchdog_set_drvdata(&wdt->wdd, NULL); |
222818c3 | 390 | |
7a23f80e TW |
391 | wdt->state = MEI_WDT_IDLE; |
392 | ||
393 | out: | |
394 | mutex_unlock(&wdt->reg_lock); | |
222818c3 TW |
395 | return ret; |
396 | } | |
397 | ||
7a23f80e TW |
398 | static void mei_wdt_unregister_work(struct work_struct *work) |
399 | { | |
400 | struct mei_wdt *wdt = container_of(work, struct mei_wdt, unregister); | |
401 | ||
402 | mei_wdt_unregister(wdt); | |
403 | } | |
404 | ||
405 | /** | |
7c7a6077 | 406 | * mei_wdt_rx - callback for data receive |
7a23f80e TW |
407 | * |
408 | * @cldev: bus device | |
409 | */ | |
7c7a6077 | 410 | static void mei_wdt_rx(struct mei_cl_device *cldev) |
7a23f80e TW |
411 | { |
412 | struct mei_wdt *wdt = mei_cldev_get_drvdata(cldev); | |
413 | struct mei_wdt_start_response res; | |
414 | const size_t res_len = sizeof(res); | |
415 | int ret; | |
416 | ||
417 | ret = mei_cldev_recv(wdt->cldev, (u8 *)&res, res_len); | |
418 | if (ret < 0) { | |
419 | dev_err(&cldev->dev, "failure in recv %d\n", ret); | |
420 | return; | |
421 | } | |
422 | ||
423 | /* Empty response can be sent on stop */ | |
424 | if (ret == 0) | |
425 | return; | |
426 | ||
427 | if (ret < sizeof(struct mei_mc_hdr)) { | |
428 | dev_err(&cldev->dev, "recv small data %d\n", ret); | |
429 | return; | |
430 | } | |
431 | ||
432 | if (res.hdr.command != MEI_MANAGEMENT_CONTROL || | |
433 | res.hdr.versionnumber != MEI_MC_VERSION_NUMBER) { | |
434 | dev_err(&cldev->dev, "wrong command received\n"); | |
435 | return; | |
436 | } | |
437 | ||
438 | if (res.hdr.subcommand != MEI_MC_START_WD_TIMER_RES) { | |
439 | dev_warn(&cldev->dev, "unsupported command %d :%s[%d]\n", | |
440 | res.hdr.subcommand, | |
441 | mei_wdt_state_str(wdt->state), | |
442 | wdt->state); | |
443 | return; | |
444 | } | |
445 | ||
446 | /* Run the unregistration in a worker as this can be | |
447 | * run only after ping completion, otherwise the flow will | |
448 | * deadlock on watchdog core mutex. | |
449 | */ | |
450 | if (wdt->state == MEI_WDT_RUNNING) { | |
451 | if (res.wdstate & MEI_WDT_WDSTATE_NOT_REQUIRED) { | |
452 | wdt->state = MEI_WDT_NOT_REQUIRED; | |
453 | schedule_work(&wdt->unregister); | |
454 | } | |
455 | goto out; | |
456 | } | |
457 | ||
458 | if (wdt->state == MEI_WDT_PROBE) { | |
459 | if (res.wdstate & MEI_WDT_WDSTATE_NOT_REQUIRED) { | |
460 | wdt->state = MEI_WDT_NOT_REQUIRED; | |
461 | } else { | |
462 | /* stop the watchdog and register watchdog device */ | |
463 | mei_wdt_stop(wdt); | |
464 | mei_wdt_register(wdt); | |
465 | } | |
466 | return; | |
467 | } | |
468 | ||
469 | dev_warn(&cldev->dev, "not in correct state %s[%d]\n", | |
470 | mei_wdt_state_str(wdt->state), wdt->state); | |
471 | ||
472 | out: | |
473 | if (!completion_done(&wdt->response)) | |
474 | complete(&wdt->response); | |
475 | } | |
476 | ||
4700df05 | 477 | /** |
7c7a6077 | 478 | * mei_wdt_notif - callback for event notification |
3a20a5c3 TW |
479 | * |
480 | * @cldev: bus device | |
481 | */ | |
7c7a6077 | 482 | static void mei_wdt_notif(struct mei_cl_device *cldev) |
3a20a5c3 TW |
483 | { |
484 | struct mei_wdt *wdt = mei_cldev_get_drvdata(cldev); | |
485 | ||
486 | if (wdt->state != MEI_WDT_NOT_REQUIRED) | |
487 | return; | |
488 | ||
489 | mei_wdt_register(wdt); | |
490 | } | |
491 | ||
c9cf20ee TW |
492 | #if IS_ENABLED(CONFIG_DEBUG_FS) |
493 | ||
ad1cd720 TW |
494 | static ssize_t mei_dbgfs_read_activation(struct file *file, char __user *ubuf, |
495 | size_t cnt, loff_t *ppos) | |
496 | { | |
497 | struct mei_wdt *wdt = file->private_data; | |
498 | const size_t bufsz = 32; | |
499 | char buf[32]; | |
500 | ssize_t pos; | |
501 | ||
502 | mutex_lock(&wdt->reg_lock); | |
503 | pos = scnprintf(buf, bufsz, "%s\n", | |
504 | __mei_wdt_is_registered(wdt) ? "activated" : "deactivated"); | |
505 | mutex_unlock(&wdt->reg_lock); | |
506 | ||
507 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, pos); | |
508 | } | |
509 | ||
510 | static const struct file_operations dbgfs_fops_activation = { | |
511 | .open = simple_open, | |
512 | .read = mei_dbgfs_read_activation, | |
513 | .llseek = generic_file_llseek, | |
514 | }; | |
515 | ||
c9cf20ee TW |
516 | static ssize_t mei_dbgfs_read_state(struct file *file, char __user *ubuf, |
517 | size_t cnt, loff_t *ppos) | |
518 | { | |
519 | struct mei_wdt *wdt = file->private_data; | |
7692a982 | 520 | char buf[32]; |
c9cf20ee TW |
521 | ssize_t pos; |
522 | ||
7692a982 TW |
523 | pos = scnprintf(buf, sizeof(buf), "state: %s\n", |
524 | mei_wdt_state_str(wdt->state)); | |
c9cf20ee TW |
525 | |
526 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, pos); | |
527 | } | |
528 | ||
529 | static const struct file_operations dbgfs_fops_state = { | |
530 | .open = simple_open, | |
531 | .read = mei_dbgfs_read_state, | |
532 | .llseek = generic_file_llseek, | |
533 | }; | |
534 | ||
535 | static void dbgfs_unregister(struct mei_wdt *wdt) | |
536 | { | |
537 | debugfs_remove_recursive(wdt->dbgfs_dir); | |
538 | wdt->dbgfs_dir = NULL; | |
539 | } | |
540 | ||
64079cf9 | 541 | static void dbgfs_register(struct mei_wdt *wdt) |
c9cf20ee | 542 | { |
64079cf9 | 543 | struct dentry *dir; |
c9cf20ee TW |
544 | |
545 | dir = debugfs_create_dir(KBUILD_MODNAME, NULL); | |
c9cf20ee | 546 | wdt->dbgfs_dir = dir; |
c9cf20ee | 547 | |
64079cf9 | 548 | debugfs_create_file("state", S_IRUSR, dir, wdt, &dbgfs_fops_state); |
ad1cd720 | 549 | |
64079cf9 GKH |
550 | debugfs_create_file("activation", S_IRUSR, dir, wdt, |
551 | &dbgfs_fops_activation); | |
c9cf20ee TW |
552 | } |
553 | ||
554 | #else | |
555 | ||
556 | static inline void dbgfs_unregister(struct mei_wdt *wdt) {} | |
64079cf9 | 557 | static inline void dbgfs_register(struct mei_wdt *wdt) {} |
c9cf20ee TW |
558 | #endif /* CONFIG_DEBUG_FS */ |
559 | ||
222818c3 TW |
560 | static int mei_wdt_probe(struct mei_cl_device *cldev, |
561 | const struct mei_cl_device_id *id) | |
562 | { | |
563 | struct mei_wdt *wdt; | |
564 | int ret; | |
565 | ||
566 | wdt = kzalloc(sizeof(struct mei_wdt), GFP_KERNEL); | |
567 | if (!wdt) | |
568 | return -ENOMEM; | |
569 | ||
570 | wdt->timeout = MEI_WDT_DEFAULT_TIMEOUT; | |
7a23f80e | 571 | wdt->state = MEI_WDT_PROBE; |
222818c3 | 572 | wdt->cldev = cldev; |
7a23f80e TW |
573 | wdt->resp_required = mei_cldev_ver(cldev) > 0x1; |
574 | mutex_init(&wdt->reg_lock); | |
575 | init_completion(&wdt->response); | |
576 | INIT_WORK(&wdt->unregister, mei_wdt_unregister_work); | |
577 | ||
222818c3 TW |
578 | mei_cldev_set_drvdata(cldev, wdt); |
579 | ||
580 | ret = mei_cldev_enable(cldev); | |
581 | if (ret < 0) { | |
582 | dev_err(&cldev->dev, "Could not enable cl device\n"); | |
583 | goto err_out; | |
584 | } | |
585 | ||
7c7a6077 AU |
586 | ret = mei_cldev_register_rx_cb(wdt->cldev, mei_wdt_rx); |
587 | if (ret) { | |
588 | dev_err(&cldev->dev, "Could not reg rx event ret=%d\n", ret); | |
589 | goto err_disable; | |
590 | } | |
3a20a5c3 | 591 | |
7c7a6077 | 592 | ret = mei_cldev_register_notif_cb(wdt->cldev, mei_wdt_notif); |
3a20a5c3 | 593 | /* on legacy devices notification is not supported |
3a20a5c3 TW |
594 | */ |
595 | if (ret && ret != -EOPNOTSUPP) { | |
7c7a6077 | 596 | dev_err(&cldev->dev, "Could not reg notif event ret=%d\n", ret); |
7a23f80e TW |
597 | goto err_disable; |
598 | } | |
599 | ||
222818c3 TW |
600 | wd_info.firmware_version = mei_cldev_ver(cldev); |
601 | ||
7a23f80e TW |
602 | if (wdt->resp_required) |
603 | ret = mei_wdt_ping(wdt); | |
604 | else | |
605 | ret = mei_wdt_register(wdt); | |
606 | ||
222818c3 TW |
607 | if (ret) |
608 | goto err_disable; | |
609 | ||
64079cf9 | 610 | dbgfs_register(wdt); |
c9cf20ee | 611 | |
222818c3 TW |
612 | return 0; |
613 | ||
614 | err_disable: | |
615 | mei_cldev_disable(cldev); | |
616 | ||
617 | err_out: | |
618 | kfree(wdt); | |
619 | ||
620 | return ret; | |
621 | } | |
622 | ||
bf5c9cc8 | 623 | static void mei_wdt_remove(struct mei_cl_device *cldev) |
222818c3 TW |
624 | { |
625 | struct mei_wdt *wdt = mei_cldev_get_drvdata(cldev); | |
626 | ||
7a23f80e TW |
627 | /* Free the caller in case of fw initiated or unexpected reset */ |
628 | if (!completion_done(&wdt->response)) | |
629 | complete(&wdt->response); | |
630 | ||
631 | cancel_work_sync(&wdt->unregister); | |
632 | ||
222818c3 TW |
633 | mei_wdt_unregister(wdt); |
634 | ||
635 | mei_cldev_disable(cldev); | |
636 | ||
c9cf20ee TW |
637 | dbgfs_unregister(wdt); |
638 | ||
222818c3 | 639 | kfree(wdt); |
222818c3 TW |
640 | } |
641 | ||
642 | #define MEI_UUID_WD UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, \ | |
643 | 0x89, 0x9D, 0xA9, 0x15, 0x14, 0xCB, 0x32, 0xAB) | |
644 | ||
4cb30b04 | 645 | static const struct mei_cl_device_id mei_wdt_tbl[] = { |
7a23f80e | 646 | { .uuid = MEI_UUID_WD, .version = MEI_CL_VERSION_ANY }, |
222818c3 TW |
647 | /* required last entry */ |
648 | { } | |
649 | }; | |
650 | MODULE_DEVICE_TABLE(mei, mei_wdt_tbl); | |
651 | ||
652 | static struct mei_cl_driver mei_wdt_driver = { | |
653 | .id_table = mei_wdt_tbl, | |
654 | .name = KBUILD_MODNAME, | |
655 | ||
656 | .probe = mei_wdt_probe, | |
657 | .remove = mei_wdt_remove, | |
658 | }; | |
659 | ||
b2a2f708 | 660 | module_mei_cl_driver(mei_wdt_driver); |
222818c3 TW |
661 | |
662 | MODULE_AUTHOR("Intel Corporation"); | |
2e62c498 | 663 | MODULE_LICENSE("GPL v2"); |
222818c3 | 664 | MODULE_DESCRIPTION("Device driver for Intel MEI iAMT watchdog"); |