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);
48 * mei_cancel_work. Cancel mei background jobs
50 * @dev: the device structure
52 * returns 0 on success or < 0 if the reset hasn't succeeded
54 void mei_cancel_work(struct mei_device *dev)
56 cancel_work_sync(&dev->init_work);
57 cancel_work_sync(&dev->reset_work);
59 cancel_delayed_work(&dev->timer_work);
61 EXPORT_SYMBOL_GPL(mei_cancel_work);
64 * mei_reset - resets host and fw.
66 * @dev: the device structure
68 int mei_reset(struct mei_device *dev)
70 enum mei_dev_state state = dev->dev_state;
71 bool interrupts_enabled;
74 if (state != MEI_DEV_INITIALIZING &&
75 state != MEI_DEV_DISABLED &&
76 state != MEI_DEV_POWER_DOWN &&
77 state != MEI_DEV_POWER_UP)
78 dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
79 mei_dev_state_str(state));
81 /* we're already in reset, cancel the init timer
82 * if the reset was called due the hbm protocol error
83 * we need to call it before hw start
84 * so the hbm watchdog won't kick in
88 /* enter reset flow */
89 interrupts_enabled = state != MEI_DEV_POWER_DOWN;
90 dev->dev_state = MEI_DEV_RESETTING;
92 ret = mei_hw_reset(dev, interrupts_enabled);
93 /* fall through and remove the sw state even if hw reset has failed */
95 /* no need to clean up software state in case of power up */
96 if (state != MEI_DEV_INITIALIZING &&
97 state != MEI_DEV_POWER_UP) {
99 /* remove all waiting requests */
100 mei_cl_all_write_clear(dev);
102 mei_cl_all_disconnect(dev);
104 /* wake up all readers and writers so they can be interrupted */
105 mei_cl_all_wakeup(dev);
107 /* remove entry if already in list */
108 dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
109 mei_cl_unlink(&dev->wd_cl);
110 mei_cl_unlink(&dev->iamthif_cl);
111 mei_amthif_reset_params(dev);
112 memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
116 dev->me_clients_num = 0;
118 dev->wd_pending = false;
121 dev_err(&dev->pdev->dev, "hw_reset failed ret = %d\n", ret);
122 dev->dev_state = MEI_DEV_DISABLED;
126 if (state == MEI_DEV_POWER_DOWN) {
127 dev_dbg(&dev->pdev->dev, "powering down: end of reset\n");
128 dev->dev_state = MEI_DEV_DISABLED;
132 ret = mei_hw_start(dev);
134 dev_err(&dev->pdev->dev, "hw_start failed ret = %d\n", ret);
135 dev->dev_state = MEI_DEV_DISABLED;
139 dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
141 dev->dev_state = MEI_DEV_INIT_CLIENTS;
142 ret = mei_hbm_start_req(dev);
144 dev_err(&dev->pdev->dev, "hbm_start failed ret = %d\n", ret);
145 dev->dev_state = MEI_DEV_DISABLED;
151 EXPORT_SYMBOL_GPL(mei_reset);
154 * mei_start - initializes host and fw to start work.
156 * @dev: the device structure
158 * returns 0 on success, <0 on failure.
160 int mei_start(struct mei_device *dev)
162 mutex_lock(&dev->device_lock);
164 /* acknowledge interrupt and stop interrupts */
165 mei_clear_interrupts(dev);
169 dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
171 dev->dev_state = MEI_DEV_INITIALIZING;
174 if (dev->dev_state == MEI_DEV_DISABLED) {
175 dev_err(&dev->pdev->dev, "reset failed");
179 if (mei_hbm_start_wait(dev)) {
180 dev_err(&dev->pdev->dev, "HBM haven't started");
184 if (!mei_host_is_ready(dev)) {
185 dev_err(&dev->pdev->dev, "host is not ready.\n");
189 if (!mei_hw_is_ready(dev)) {
190 dev_err(&dev->pdev->dev, "ME is not ready.\n");
194 if (!mei_hbm_version_is_supported(dev)) {
195 dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
199 dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
201 mutex_unlock(&dev->device_lock);
204 dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
205 dev->dev_state = MEI_DEV_DISABLED;
206 mutex_unlock(&dev->device_lock);
209 EXPORT_SYMBOL_GPL(mei_start);
212 * mei_restart - restart device after suspend
214 * @dev: the device structure
216 * returns 0 on success or -ENODEV if the restart hasn't succeeded
218 int mei_restart(struct mei_device *dev)
222 mutex_lock(&dev->device_lock);
224 mei_clear_interrupts(dev);
226 dev->dev_state = MEI_DEV_POWER_UP;
228 err = mei_reset(dev);
230 mutex_unlock(&dev->device_lock);
232 if (err || dev->dev_state == MEI_DEV_DISABLED)
237 EXPORT_SYMBOL_GPL(mei_restart);
240 static void mei_reset_work(struct work_struct *work)
242 struct mei_device *dev =
243 container_of(work, struct mei_device, reset_work);
245 mutex_lock(&dev->device_lock);
249 mutex_unlock(&dev->device_lock);
251 if (dev->dev_state == MEI_DEV_DISABLED)
252 dev_err(&dev->pdev->dev, "reset failed");
255 void mei_stop(struct mei_device *dev)
257 dev_dbg(&dev->pdev->dev, "stopping the device.\n");
259 mei_cancel_work(dev);
261 mei_nfc_host_exit(dev);
263 mutex_lock(&dev->device_lock);
267 dev->dev_state = MEI_DEV_POWER_DOWN;
270 mutex_unlock(&dev->device_lock);
272 mei_watchdog_unregister(dev);
274 EXPORT_SYMBOL_GPL(mei_stop);
278 void mei_device_init(struct mei_device *dev)
280 /* setup our list array */
281 INIT_LIST_HEAD(&dev->file_list);
282 INIT_LIST_HEAD(&dev->device_list);
283 mutex_init(&dev->device_lock);
284 init_waitqueue_head(&dev->wait_hw_ready);
285 init_waitqueue_head(&dev->wait_recvd_msg);
286 init_waitqueue_head(&dev->wait_stop_wd);
287 dev->dev_state = MEI_DEV_INITIALIZING;
289 mei_io_list_init(&dev->read_list);
290 mei_io_list_init(&dev->write_list);
291 mei_io_list_init(&dev->write_waiting_list);
292 mei_io_list_init(&dev->ctrl_wr_list);
293 mei_io_list_init(&dev->ctrl_rd_list);
295 INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
296 INIT_WORK(&dev->init_work, mei_host_client_init);
297 INIT_WORK(&dev->reset_work, mei_reset_work);
299 INIT_LIST_HEAD(&dev->wd_cl.link);
300 INIT_LIST_HEAD(&dev->iamthif_cl.link);
301 mei_io_list_init(&dev->amthif_cmd_list);
302 mei_io_list_init(&dev->amthif_rd_complete_list);
304 bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
305 dev->open_handle_count = 0;
308 * Reserving the first client ID
309 * 0: Reserved for MEI Bus Message communications
311 bitmap_set(dev->host_clients_map, 0, 1);
313 EXPORT_SYMBOL_GPL(mei_device_init);