3 * Intel Management Engine Interface (Intel MEI) Linux driver
4 * Copyright (c) 2003-2012, Intel Corporation.
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.
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
17 #include <linux/export.h>
18 #include <linux/pci.h>
19 #include <linux/sched.h>
20 #include <linux/wait.h>
21 #include <linux/delay.h>
23 #include <linux/mei.h>
29 const char *mei_dev_state_str(int state)
31 #define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
33 MEI_DEV_STATE(INITIALIZING);
34 MEI_DEV_STATE(INIT_CLIENTS);
35 MEI_DEV_STATE(ENABLED);
36 MEI_DEV_STATE(RESETTING);
37 MEI_DEV_STATE(DISABLED);
38 MEI_DEV_STATE(POWER_DOWN);
39 MEI_DEV_STATE(POWER_UP);
46 void mei_device_init(struct mei_device *dev)
48 /* setup our list array */
49 INIT_LIST_HEAD(&dev->file_list);
50 INIT_LIST_HEAD(&dev->device_list);
51 mutex_init(&dev->device_lock);
52 init_waitqueue_head(&dev->wait_hw_ready);
53 init_waitqueue_head(&dev->wait_recvd_msg);
54 init_waitqueue_head(&dev->wait_stop_wd);
55 dev->dev_state = MEI_DEV_INITIALIZING;
57 mei_io_list_init(&dev->read_list);
58 mei_io_list_init(&dev->write_list);
59 mei_io_list_init(&dev->write_waiting_list);
60 mei_io_list_init(&dev->ctrl_wr_list);
61 mei_io_list_init(&dev->ctrl_rd_list);
63 INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
64 INIT_WORK(&dev->init_work, mei_host_client_init);
66 INIT_LIST_HEAD(&dev->wd_cl.link);
67 INIT_LIST_HEAD(&dev->iamthif_cl.link);
68 mei_io_list_init(&dev->amthif_cmd_list);
69 mei_io_list_init(&dev->amthif_rd_complete_list);
72 EXPORT_SYMBOL_GPL(mei_device_init);
75 * mei_start - initializes host and fw to start work.
77 * @dev: the device structure
79 * returns 0 on success, <0 on failure.
81 int mei_start(struct mei_device *dev)
83 mutex_lock(&dev->device_lock);
85 /* acknowledge interrupt and stop interupts */
86 mei_clear_interrupts(dev);
90 dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
94 if (mei_hbm_start_wait(dev)) {
95 dev_err(&dev->pdev->dev, "HBM haven't started");
99 if (!mei_host_is_ready(dev)) {
100 dev_err(&dev->pdev->dev, "host is not ready.\n");
104 if (!mei_hw_is_ready(dev)) {
105 dev_err(&dev->pdev->dev, "ME is not ready.\n");
109 if (!mei_hbm_version_is_supported(dev)) {
110 dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
114 dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
116 mutex_unlock(&dev->device_lock);
119 dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
120 dev->dev_state = MEI_DEV_DISABLED;
121 mutex_unlock(&dev->device_lock);
124 EXPORT_SYMBOL_GPL(mei_start);
127 * mei_reset - resets host and fw.
129 * @dev: the device structure
130 * @interrupts_enabled: if interrupt should be enabled after reset.
132 void mei_reset(struct mei_device *dev, int interrupts_enabled)
136 unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
137 dev->dev_state != MEI_DEV_DISABLED &&
138 dev->dev_state != MEI_DEV_POWER_DOWN &&
139 dev->dev_state != MEI_DEV_POWER_UP);
141 mei_hw_reset(dev, interrupts_enabled);
143 dev->hbm_state = MEI_HBM_IDLE;
145 if (dev->dev_state != MEI_DEV_INITIALIZING) {
146 if (dev->dev_state != MEI_DEV_DISABLED &&
147 dev->dev_state != MEI_DEV_POWER_DOWN)
148 dev->dev_state = MEI_DEV_RESETTING;
150 mei_cl_all_disconnect(dev);
152 /* remove entry if already in list */
153 dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
154 mei_cl_unlink(&dev->wd_cl);
155 if (dev->open_handle_count > 0)
156 dev->open_handle_count--;
157 mei_cl_unlink(&dev->iamthif_cl);
158 if (dev->open_handle_count > 0)
159 dev->open_handle_count--;
161 mei_amthif_reset_params(dev);
162 memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
165 dev->me_clients_num = 0;
167 dev->wd_pending = false;
170 dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
171 mei_dev_state_str(dev->dev_state));
173 if (!interrupts_enabled) {
174 dev_dbg(&dev->pdev->dev, "intr not enabled end of reset\n");
180 dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
181 /* link is established * start sending messages. */
183 dev->dev_state = MEI_DEV_INIT_CLIENTS;
185 mei_hbm_start_req(dev);
187 /* wake up all readings so they can be interrupted */
188 mei_cl_all_read_wakeup(dev);
190 /* remove all waiting requests */
191 mei_cl_all_write_clear(dev);
193 EXPORT_SYMBOL_GPL(mei_reset);
195 void mei_stop(struct mei_device *dev)
197 dev_dbg(&dev->pdev->dev, "stopping the device.\n");
199 flush_scheduled_work();
201 mutex_lock(&dev->device_lock);
203 cancel_delayed_work(&dev->timer_work);
209 dev->dev_state = MEI_DEV_POWER_DOWN;
212 mutex_unlock(&dev->device_lock);
214 mei_watchdog_unregister(dev);
216 EXPORT_SYMBOL_GPL(mei_stop);