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
|
/*
* ChromeOS EC multi-function device
*
* Copyright (C) 2012 Google, Inc
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* The ChromeOS EC multi function device is used to mux all the requests
* to the EC device for its multiple features: keyboard controller,
* battery charging and regulator control, firmware update.
*/
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mfd/core.h>
#include <linux/mfd/cros_ec.h>
#include <linux/mfd/cros_ec_commands.h>
#include <linux/delay.h>
#define EC_COMMAND_RETRIES 50
int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
uint8_t *out;
int csum, i;
BUG_ON(msg->outsize > EC_PROTO2_MAX_PARAM_SIZE);
out = ec_dev->dout;
out[0] = EC_CMD_VERSION0 + msg->version;
out[1] = msg->command;
out[2] = msg->outsize;
csum = out[0] + out[1] + out[2];
for (i = 0; i < msg->outsize; i++)
csum += out[EC_MSG_TX_HEADER_BYTES + i] = msg->outdata[i];
out[EC_MSG_TX_HEADER_BYTES + msg->outsize] = (uint8_t)(csum & 0xff);
return EC_MSG_TX_PROTO_BYTES + msg->outsize;
}
EXPORT_SYMBOL(cros_ec_prepare_tx);
int cros_ec_check_result(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
switch (msg->result) {
case EC_RES_SUCCESS:
return 0;
case EC_RES_IN_PROGRESS:
dev_dbg(ec_dev->dev, "command 0x%02x in progress\n",
msg->command);
return -EAGAIN;
default:
dev_dbg(ec_dev->dev, "command 0x%02x returned %d\n",
msg->command, msg->result);
return 0;
}
}
EXPORT_SYMBOL(cros_ec_check_result);
int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
int ret;
mutex_lock(&ec_dev->lock);
ret = ec_dev->cmd_xfer(ec_dev, msg);
if (msg->result == EC_RES_IN_PROGRESS) {
int i;
struct cros_ec_command status_msg = { };
struct ec_response_get_comms_status *status;
status_msg.command = EC_CMD_GET_COMMS_STATUS;
status_msg.insize = sizeof(*status);
/*
* Query the EC's status until it's no longer busy or
* we encounter an error.
*/
for (i = 0; i < EC_COMMAND_RETRIES; i++) {
usleep_range(10000, 11000);
ret = ec_dev->cmd_xfer(ec_dev, &status_msg);
if (ret < 0)
break;
msg->result = status_msg.result;
if (status_msg.result != EC_RES_SUCCESS)
break;
status = (struct ec_response_get_comms_status *)
status_msg.indata;
if (!(status->flags & EC_COMMS_STATUS_PROCESSING))
break;
}
}
mutex_unlock(&ec_dev->lock);
return ret;
}
EXPORT_SYMBOL(cros_ec_cmd_xfer);
static const struct mfd_cell cros_devs[] = {
{
.name = "cros-ec-keyb",
.id = 1,
.of_compatible = "google,cros-ec-keyb",
},
{
.name = "cros-ec-i2c-tunnel",
.id = 2,
.of_compatible = "google,cros-ec-i2c-tunnel",
},
{
.name = "cros-ec-ctl",
.id = 3,
},
};
int cros_ec_register(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
int err = 0;
if (ec_dev->din_size) {
ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
if (!ec_dev->din)
return -ENOMEM;
}
if (ec_dev->dout_size) {
ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
if (!ec_dev->dout)
return -ENOMEM;
}
mutex_init(&ec_dev->lock);
err = mfd_add_devices(dev, 0, cros_devs,
ARRAY_SIZE(cros_devs),
NULL, ec_dev->irq, NULL);
if (err) {
dev_err(dev, "failed to add mfd devices\n");
return err;
}
dev_info(dev, "Chrome EC device registered\n");
return 0;
}
EXPORT_SYMBOL(cros_ec_register);
int cros_ec_remove(struct cros_ec_device *ec_dev)
{
mfd_remove_devices(ec_dev->dev);
return 0;
}
EXPORT_SYMBOL(cros_ec_remove);
#ifdef CONFIG_PM_SLEEP
int cros_ec_suspend(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
if (device_may_wakeup(dev))
ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
disable_irq(ec_dev->irq);
ec_dev->was_wake_device = ec_dev->wake_enabled;
return 0;
}
EXPORT_SYMBOL(cros_ec_suspend);
int cros_ec_resume(struct cros_ec_device *ec_dev)
{
enable_irq(ec_dev->irq);
if (ec_dev->wake_enabled) {
disable_irq_wake(ec_dev->irq);
ec_dev->wake_enabled = 0;
}
return 0;
}
EXPORT_SYMBOL(cros_ec_resume);
#endif
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ChromeOS EC core driver");
|
