1 // SPDX-License-Identifier: GPL-2.0
40  * enum mei_wdt_state - internal watchdog state
43  * @MEI_WDT_IDLE: wd is idle and not opened
47  * @MEI_WDT_NOT_REQUIRED: wd device is not required
79  * struct mei_wdt - mei watchdog driver
109  * struct mei_mc_hdr - Management Control Command Header
124  * struct mei_wdt_start_request - watchdog start/ping
137  * struct mei_wdt_start_response - watchdog start/ping response
150  * struct mei_wdt_stop_request - watchdog stop
159  * mei_wdt_ping - send wd start/ping command
174 	req.hdr.bytecount = req_len - offsetof(struct mei_mc_hdr, subcommand);  in mei_wdt_ping()
177 	req.timeout = wdt->timeout;  in mei_wdt_ping()
179 	ret = mei_cldev_send(wdt->cldev, (u8 *)&req, req_len);  in mei_wdt_ping()
187  * mei_wdt_stop - send wd stop command
202 	req.hdr.bytecount = req_len - offsetof(struct mei_mc_hdr, subcommand);  in mei_wdt_stop()
206 	ret = mei_cldev_send(wdt->cldev, (u8 *)&req, req_len);  in mei_wdt_stop()
214  * mei_wdt_ops_start - wd start command from the watchdog core.
218  * Return: 0 on success or -ENODEV;
224 	wdt->state = MEI_WDT_START;  in mei_wdt_ops_start()
225 	wdd->timeout = wdt->timeout;  in mei_wdt_ops_start()
230  * mei_wdt_ops_stop - wd stop command from the watchdog core.
241 	if (wdt->state != MEI_WDT_RUNNING)  in mei_wdt_ops_stop()
244 	wdt->state = MEI_WDT_STOPPING;  in mei_wdt_ops_stop()
250 	wdt->state = MEI_WDT_IDLE;  in mei_wdt_ops_stop()
256  * mei_wdt_ops_ping - wd ping command from the watchdog core.
267 	if (wdt->state != MEI_WDT_START && wdt->state != MEI_WDT_RUNNING)  in mei_wdt_ops_ping()
270 	if (wdt->resp_required)  in mei_wdt_ops_ping()
271 		init_completion(&wdt->response);  in mei_wdt_ops_ping()
273 	wdt->state = MEI_WDT_RUNNING;  in mei_wdt_ops_ping()
278 	if (wdt->resp_required)  in mei_wdt_ops_ping()
279 		ret = wait_for_completion_killable(&wdt->response);  in mei_wdt_ops_ping()
285  * mei_wdt_ops_set_timeout - wd set timeout command from the watchdog core.
299 	wdt->timeout = timeout;  in mei_wdt_ops_set_timeout()
300 	wdd->timeout = timeout;  in mei_wdt_ops_set_timeout()
313 /* not const as the firmware_version field need to be retrieved */
322  * __mei_wdt_is_registered - check if wdt is registered
327  * Locking: should be called under wdt->reg_lock
331 	return !!watchdog_get_drvdata(&wdt->wdd);  in __mei_wdt_is_registered()
335  * mei_wdt_unregister - unregister from the watchdog subsystem
341 	mutex_lock(&wdt->reg_lock);  in mei_wdt_unregister()
344 		watchdog_unregister_device(&wdt->wdd);  in mei_wdt_unregister()
345 		watchdog_set_drvdata(&wdt->wdd, NULL);  in mei_wdt_unregister()
346 		memset(&wdt->wdd, 0, sizeof(wdt->wdd));  in mei_wdt_unregister()
349 	mutex_unlock(&wdt->reg_lock);  in mei_wdt_unregister()
353  * mei_wdt_register - register with the watchdog subsystem
364 	if (!wdt || !wdt->cldev)  in mei_wdt_register()
365 		return -EINVAL;  in mei_wdt_register()
367 	dev = &wdt->cldev->dev;  in mei_wdt_register()
369 	mutex_lock(&wdt->reg_lock);  in mei_wdt_register()
376 	wdt->wdd.info = &wd_info;  in mei_wdt_register()
377 	wdt->wdd.ops = &wd_ops;  in mei_wdt_register()
378 	wdt->wdd.parent = dev;  in mei_wdt_register()
379 	wdt->wdd.timeout = MEI_WDT_DEFAULT_TIMEOUT;  in mei_wdt_register()
380 	wdt->wdd.min_timeout = MEI_WDT_MIN_TIMEOUT;  in mei_wdt_register()
381 	wdt->wdd.max_timeout = MEI_WDT_MAX_TIMEOUT;  in mei_wdt_register()
383 	watchdog_set_drvdata(&wdt->wdd, wdt);  in mei_wdt_register()
384 	watchdog_stop_on_reboot(&wdt->wdd);  in mei_wdt_register()
385 	watchdog_stop_on_unregister(&wdt->wdd);  in mei_wdt_register()
387 	ret = watchdog_register_device(&wdt->wdd);  in mei_wdt_register()
389 		watchdog_set_drvdata(&wdt->wdd, NULL);  in mei_wdt_register()
391 	wdt->state = MEI_WDT_IDLE;  in mei_wdt_register()
394 	mutex_unlock(&wdt->reg_lock);  in mei_wdt_register()
406  * mei_wdt_rx - callback for data receive
417 	ret = mei_cldev_recv(wdt->cldev, (u8 *)&res, res_len);  in mei_wdt_rx()
419 		dev_err(&cldev->dev, "failure in recv %d\n", ret);  in mei_wdt_rx()
423 	/* Empty response can be sent on stop */  in mei_wdt_rx()
428 		dev_err(&cldev->dev, "recv small data %d\n", ret);  in mei_wdt_rx()
434 		dev_err(&cldev->dev, "wrong command received\n");  in mei_wdt_rx()
439 		dev_warn(&cldev->dev, "unsupported command %d :%s[%d]\n",  in mei_wdt_rx()
441 			 mei_wdt_state_str(wdt->state),  in mei_wdt_rx()
442 			 wdt->state);  in mei_wdt_rx()
450 	if (wdt->state == MEI_WDT_RUNNING) {  in mei_wdt_rx()
452 			wdt->state = MEI_WDT_NOT_REQUIRED;  in mei_wdt_rx()
453 			schedule_work(&wdt->unregister);  in mei_wdt_rx()
458 	if (wdt->state == MEI_WDT_PROBE) {  in mei_wdt_rx()
460 			wdt->state = MEI_WDT_NOT_REQUIRED;  in mei_wdt_rx()
469 	dev_warn(&cldev->dev, "not in correct state %s[%d]\n",  in mei_wdt_rx()
470 			 mei_wdt_state_str(wdt->state), wdt->state);  in mei_wdt_rx()
473 	if (!completion_done(&wdt->response))  in mei_wdt_rx()
474 		complete(&wdt->response);  in mei_wdt_rx()
478  * mei_wdt_notif - callback for event notification
486 	if (wdt->state != MEI_WDT_NOT_REQUIRED)  in mei_wdt_notif()
497 	struct mei_wdt *wdt = file->private_data;  in mei_dbgfs_read_activation()
502 	mutex_lock(&wdt->reg_lock);  in mei_dbgfs_read_activation()
505 	mutex_unlock(&wdt->reg_lock);  in mei_dbgfs_read_activation()
519 	struct mei_wdt *wdt = file->private_data;  in mei_dbgfs_read_state()
524 			mei_wdt_state_str(wdt->state));  in mei_dbgfs_read_state()
537 	debugfs_remove_recursive(wdt->dbgfs_dir);  in dbgfs_unregister()
538 	wdt->dbgfs_dir = NULL;  in dbgfs_unregister()
546 	wdt->dbgfs_dir = dir;  in dbgfs_register()
568 		return -ENOMEM;  in mei_wdt_probe()
570 	wdt->timeout = MEI_WDT_DEFAULT_TIMEOUT;  in mei_wdt_probe()
571 	wdt->state = MEI_WDT_PROBE;  in mei_wdt_probe()
572 	wdt->cldev = cldev;  in mei_wdt_probe()
573 	wdt->resp_required = mei_cldev_ver(cldev) > 0x1;  in mei_wdt_probe()
574 	mutex_init(&wdt->reg_lock);  in mei_wdt_probe()
575 	init_completion(&wdt->response);  in mei_wdt_probe()
576 	INIT_WORK(&wdt->unregister, mei_wdt_unregister_work);  in mei_wdt_probe()
582 		dev_err(&cldev->dev, "Could not enable cl device\n");  in mei_wdt_probe()
586 	ret = mei_cldev_register_rx_cb(wdt->cldev, mei_wdt_rx);  in mei_wdt_probe()
588 		dev_err(&cldev->dev, "Could not reg rx event ret=%d\n", ret);  in mei_wdt_probe()
592 	ret = mei_cldev_register_notif_cb(wdt->cldev, mei_wdt_notif);  in mei_wdt_probe()
593 	/* on legacy devices notification is not supported  in mei_wdt_probe()
595 	if (ret && ret != -EOPNOTSUPP) {  in mei_wdt_probe()
596 		dev_err(&cldev->dev, "Could not reg notif event ret=%d\n", ret);  in mei_wdt_probe()
602 	if (wdt->resp_required)  in mei_wdt_probe()
628 	if (!completion_done(&wdt->response))  in mei_wdt_remove()
629 		complete(&wdt->response);  in mei_wdt_remove()
631 	cancel_work_sync(&wdt->unregister);  in mei_wdt_remove()