1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright © 2020 - 2021 Intel Corporation
*/
/**
* DOC: MEI_PXP Client Driver
*
* The mei_pxp driver acts as a translation layer between PXP
* protocol implementer (I915) and ME FW by translating PXP
* negotiation messages to ME FW command payloads and vice versa.
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/uuid.h>
#include <linux/mei_cl_bus.h>
#include <linux/component.h>
#include <drm/drm_connector.h>
#include <drm/i915_component.h>
#include <drm/i915_pxp_tee_interface.h>
#include "mei_pxp.h"
/**
* mei_pxp_send_message() - Sends a PXP message to ME FW.
* @dev: device corresponding to the mei_cl_device
* @message: a message buffer to send
* @size: size of the message
* Return: 0 on Success, <0 on Failure
*/
static int
mei_pxp_send_message(struct device *dev, const void *message, size_t size)
{
struct mei_cl_device *cldev;
ssize_t byte;
if (!dev || !message)
return -EINVAL;
cldev = to_mei_cl_device(dev);
/* temporary drop const qualifier till the API is fixed */
byte = mei_cldev_send(cldev, (u8 *)message, size);
if (byte < 0) {
dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
return byte;
}
return 0;
}
/**
* mei_pxp_receive_message() - Receives a PXP message from ME FW.
* @dev: device corresponding to the mei_cl_device
* @buffer: a message buffer to contain the received message
* @size: size of the buffer
* Return: bytes sent on Success, <0 on Failure
*/
static int
mei_pxp_receive_message(struct device *dev, void *buffer, size_t size)
{
struct mei_cl_device *cldev;
ssize_t byte;
if (!dev || !buffer)
return -EINVAL;
cldev = to_mei_cl_device(dev);
byte = mei_cldev_recv(cldev, buffer, size);
if (byte < 0) {
dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
return byte;
}
return byte;
}
static const struct i915_pxp_component_ops mei_pxp_ops = {
.owner = THIS_MODULE,
.send = mei_pxp_send_message,
.recv = mei_pxp_receive_message,
};
static int mei_component_master_bind(struct device *dev)
{
struct mei_cl_device *cldev = to_mei_cl_device(dev);
struct i915_pxp_component *comp_master = mei_cldev_get_drvdata(cldev);
int ret;
comp_master->ops = &mei_pxp_ops;
comp_master->tee_dev = dev;
ret = component_bind_all(dev, comp_master);
if (ret < 0)
return ret;
return 0;
}
static void mei_component_master_unbind(struct device *dev)
{
struct mei_cl_device *cldev = to_mei_cl_device(dev);
struct i915_pxp_component *comp_master = mei_cldev_get_drvdata(cldev);
component_unbind_all(dev, comp_master);
}
static const struct component_master_ops mei_component_master_ops = {
.bind = mei_component_master_bind,
.unbind = mei_component_master_unbind,
};
/**
* mei_pxp_component_match - compare function for matching mei pxp.
*
* The function checks if the driver is i915, the subcomponent is PXP
* and the grand parent of pxp and the parent of i915 are the same
* PCH device.
*
* @dev: master device
* @subcomponent: subcomponent to match (I915_COMPONENT_PXP)
* @data: compare data (mei pxp device)
*
* Return:
* * 1 - if components match
* * 0 - otherwise
*/
static int mei_pxp_component_match(struct device *dev, int subcomponent,
void *data)
{
struct device *base = data;
if (strcmp(dev->driver->name, "i915") ||
subcomponent != I915_COMPONENT_PXP)
return 0;
base = base->parent;
if (!base)
return 0;
base = base->parent;
dev = dev->parent;
return (base && dev && dev == base);
}
static int mei_pxp_probe(struct mei_cl_device *cldev,
const struct mei_cl_device_id *id)
{
struct i915_pxp_component *comp_master;
struct component_match *master_match;
int ret;
ret = mei_cldev_enable(cldev);
if (ret < 0) {
dev_err(&cldev->dev, "mei_cldev_enable Failed. %d\n", ret);
goto enable_err_exit;
}
comp_master = kzalloc(sizeof(*comp_master), GFP_KERNEL);
if (!comp_master) {
ret = -ENOMEM;
goto err_exit;
}
master_match = NULL;
component_match_add_typed(&cldev->dev, &master_match,
mei_pxp_component_match, &cldev->dev);
if (IS_ERR_OR_NULL(master_match)) {
ret = -ENOMEM;
goto err_exit;
}
mei_cldev_set_drvdata(cldev, comp_master);
ret = component_master_add_with_match(&cldev->dev,
&mei_component_master_ops,
master_match);
if (ret < 0) {
dev_err(&cldev->dev, "Master comp add failed %d\n", ret);
goto err_exit;
}
return 0;
err_exit:
mei_cldev_set_drvdata(cldev, NULL);
kfree(comp_master);
mei_cldev_disable(cldev);
enable_err_exit:
return ret;
}
static void mei_pxp_remove(struct mei_cl_device *cldev)
{
struct i915_pxp_component *comp_master = mei_cldev_get_drvdata(cldev);
int ret;
component_master_del(&cldev->dev, &mei_component_master_ops);
kfree(comp_master);
mei_cldev_set_drvdata(cldev, NULL);
ret = mei_cldev_disable(cldev);
if (ret)
dev_warn(&cldev->dev, "mei_cldev_disable() failed\n");
}
/* fbf6fcf1-96cf-4e2e-a6a6-1bab8cbe36b1 : PAVP GUID*/
#define MEI_GUID_PXP GUID_INIT(0xfbf6fcf1, 0x96cf, 0x4e2e, 0xA6, \
0xa6, 0x1b, 0xab, 0x8c, 0xbe, 0x36, 0xb1)
static struct mei_cl_device_id mei_pxp_tbl[] = {
{ .uuid = MEI_GUID_PXP, .version = MEI_CL_VERSION_ANY },
{ }
};
MODULE_DEVICE_TABLE(mei, mei_pxp_tbl);
static struct mei_cl_driver mei_pxp_driver = {
.id_table = mei_pxp_tbl,
.name = KBUILD_MODNAME,
.probe = mei_pxp_probe,
.remove = mei_pxp_remove,
};
module_mei_cl_driver(mei_pxp_driver);
MODULE_AUTHOR("Intel Corporation");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MEI PXP");
|
