Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[firefly-linux-kernel-4.4.55.git] / drivers / misc / mei / init.c
1 /*
2  *
3  * Intel Management Engine Interface (Intel MEI) Linux driver
4  * Copyright (c) 2003-2012, Intel Corporation.
5  *
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.
9  *
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
13  * more details.
14  *
15  */
16
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>
22
23 #include <linux/mei.h>
24
25 #include "mei_dev.h"
26 #include "hbm.h"
27 #include "client.h"
28
29 const char *mei_dev_state_str(int state)
30 {
31 #define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
32         switch (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);
40         default:
41                 return "unknown";
42         }
43 #undef MEI_DEV_STATE
44 }
45
46 void mei_device_init(struct mei_device *dev)
47 {
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;
56
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);
62
63         INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
64         INIT_WORK(&dev->init_work, mei_host_client_init);
65
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);
70
71 }
72 EXPORT_SYMBOL_GPL(mei_device_init);
73
74 /**
75  * mei_start - initializes host and fw to start work.
76  *
77  * @dev: the device structure
78  *
79  * returns 0 on success, <0 on failure.
80  */
81 int mei_start(struct mei_device *dev)
82 {
83         mutex_lock(&dev->device_lock);
84
85         /* acknowledge interrupt and stop interupts */
86         mei_clear_interrupts(dev);
87
88         mei_hw_config(dev);
89
90         dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
91
92         mei_reset(dev, 1);
93
94         if (mei_hbm_start_wait(dev)) {
95                 dev_err(&dev->pdev->dev, "HBM haven't started");
96                 goto err;
97         }
98
99         if (!mei_host_is_ready(dev)) {
100                 dev_err(&dev->pdev->dev, "host is not ready.\n");
101                 goto err;
102         }
103
104         if (!mei_hw_is_ready(dev)) {
105                 dev_err(&dev->pdev->dev, "ME is not ready.\n");
106                 goto err;
107         }
108
109         if (!mei_hbm_version_is_supported(dev)) {
110                 dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
111                 goto err;
112         }
113
114         dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
115
116         mutex_unlock(&dev->device_lock);
117         return 0;
118 err:
119         dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
120         dev->dev_state = MEI_DEV_DISABLED;
121         mutex_unlock(&dev->device_lock);
122         return -ENODEV;
123 }
124 EXPORT_SYMBOL_GPL(mei_start);
125
126 /**
127  * mei_reset - resets host and fw.
128  *
129  * @dev: the device structure
130  * @interrupts_enabled: if interrupt should be enabled after reset.
131  */
132 void mei_reset(struct mei_device *dev, int interrupts_enabled)
133 {
134         bool unexpected;
135         int ret;
136
137         unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
138                         dev->dev_state != MEI_DEV_DISABLED &&
139                         dev->dev_state != MEI_DEV_POWER_DOWN &&
140                         dev->dev_state != MEI_DEV_POWER_UP);
141
142         ret = mei_hw_reset(dev, interrupts_enabled);
143         if (ret) {
144                 dev_err(&dev->pdev->dev, "hw reset failed disabling the device\n");
145                 interrupts_enabled = false;
146                 dev->dev_state = MEI_DEV_DISABLED;
147         }
148
149         dev->hbm_state = MEI_HBM_IDLE;
150
151         if (dev->dev_state != MEI_DEV_INITIALIZING &&
152             dev->dev_state != MEI_DEV_POWER_UP) {
153                 if (dev->dev_state != MEI_DEV_DISABLED &&
154                     dev->dev_state != MEI_DEV_POWER_DOWN)
155                         dev->dev_state = MEI_DEV_RESETTING;
156
157                 mei_cl_all_disconnect(dev);
158
159                 /* remove entry if already in list */
160                 dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
161                 mei_cl_unlink(&dev->wd_cl);
162                 if (dev->open_handle_count > 0)
163                         dev->open_handle_count--;
164                 mei_cl_unlink(&dev->iamthif_cl);
165                 if (dev->open_handle_count > 0)
166                         dev->open_handle_count--;
167
168                 mei_amthif_reset_params(dev);
169                 memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
170         }
171
172         dev->me_clients_num = 0;
173         dev->rd_msg_hdr = 0;
174         dev->wd_pending = false;
175
176         if (unexpected)
177                 dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
178                          mei_dev_state_str(dev->dev_state));
179
180         if (!interrupts_enabled) {
181                 dev_dbg(&dev->pdev->dev, "intr not enabled end of reset\n");
182                 return;
183         }
184
185         ret = mei_hw_start(dev);
186         if (ret) {
187                 dev_err(&dev->pdev->dev, "hw_start failed disabling the device\n");
188                 dev->dev_state = MEI_DEV_DISABLED;
189                 return;
190         }
191
192         dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
193         /* link is established * start sending messages.  */
194
195         dev->dev_state = MEI_DEV_INIT_CLIENTS;
196
197         mei_hbm_start_req(dev);
198
199         /* wake up all readings so they can be interrupted */
200         mei_cl_all_read_wakeup(dev);
201
202         /* remove all waiting requests */
203         mei_cl_all_write_clear(dev);
204 }
205 EXPORT_SYMBOL_GPL(mei_reset);
206
207 void mei_stop(struct mei_device *dev)
208 {
209         dev_dbg(&dev->pdev->dev, "stopping the device.\n");
210
211         flush_scheduled_work();
212
213         mutex_lock(&dev->device_lock);
214
215         cancel_delayed_work(&dev->timer_work);
216
217         mei_wd_stop(dev);
218
219         mei_nfc_host_exit();
220
221         dev->dev_state = MEI_DEV_POWER_DOWN;
222         mei_reset(dev, 0);
223
224         mutex_unlock(&dev->device_lock);
225
226         mei_watchdog_unregister(dev);
227 }
228 EXPORT_SYMBOL_GPL(mei_stop);
229
230
231