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
230
231
232
233
|
/*
* AD5820 focuser driver.
*
* Copyright (C) 2010-2011 NVIDIA Corporation.
*
* Contributors:
* Sachin Nikam <snikam@nvidia.com>
*
* Based on ov5650.c.
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/i2c.h>
#include <linux/miscdevice.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <media/ad5820.h>
/* Focuser single step & full scale transition time truth table
* in the format of:
* index mode single step transition full scale transition
* 0 0 0 0
* 1 1 50uS 51.2mS
* 2 1 100uS 102.3mS
* 3 1 200uS 204.6mS
* 4 1 400uS 409.2mS
* 5 1 800uS 818.4mS
* 6 1 1600uS 1636.8mS
* 7 1 3200uS 3273.6mS
* 8 0 0 0
* 9 2 50uS 1.1mS
* A 2 100uS 2.2mS
* B 2 200uS 4.4mS
* C 2 400uS 8.8mS
* D 2 800uS 17.6mS
* E 2 1600uS 35.2mS
* F 2 3200uS 70.4mS
*/
/* pick up the mode index setting and its settle time from the above table */
#define AD5820_TRANSITION_MODE 0x0B
#define SETTLETIME_MS 5
#define POS_LOW (0)
#define POS_HIGH (1023)
#define FOCAL_LENGTH (4.507f)
#define FNUMBER (2.8f)
#define FPOS_COUNT 1024
struct ad5820_info {
struct i2c_client *i2c_client;
struct regulator *regulator;
struct ad5820_config config;
};
static int ad5820_write(struct i2c_client *client, u32 value)
{
int count;
struct i2c_msg msg[1];
unsigned char data[2];
if (!client->adapter)
return -ENODEV;
data[0] = (u8) ((value >> 4) & 0x3F);
data[1] = (u8) ((value & 0xF) << 4) | AD5820_TRANSITION_MODE;
msg[0].addr = client->addr;
msg[0].flags = 0;
msg[0].len = ARRAY_SIZE(data);
msg[0].buf = data;
count = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
if (count == ARRAY_SIZE(msg))
return 0;
return -EIO;
}
static int ad5820_set_position(struct ad5820_info *info, u32 position)
{
if (position < info->config.pos_low ||
position > info->config.pos_high)
return -EINVAL;
return ad5820_write(info->i2c_client, position);
}
static long ad5820_ioctl(struct file *file,
unsigned int cmd, unsigned long arg)
{
struct ad5820_info *info = file->private_data;
switch (cmd) {
case AD5820_IOCTL_GET_CONFIG:
{
if (copy_to_user((void __user *) arg,
&info->config,
sizeof(info->config))) {
pr_err("%s: 0x%x\n", __func__, __LINE__);
return -EFAULT;
}
break;
}
case AD5820_IOCTL_SET_POSITION:
return ad5820_set_position(info, (u32) arg);
default:
return -EINVAL;
}
return 0;
}
struct ad5820_info *info;
static int ad5820_open(struct inode *inode, struct file *file)
{
file->private_data = info;
if (info->regulator)
regulator_enable(info->regulator);
return 0;
}
int ad5820_release(struct inode *inode, struct file *file)
{
if (info->regulator)
regulator_disable(info->regulator);
file->private_data = NULL;
return 0;
}
static const struct file_operations ad5820_fileops = {
.owner = THIS_MODULE,
.open = ad5820_open,
.unlocked_ioctl = ad5820_ioctl,
.release = ad5820_release,
};
static struct miscdevice ad5820_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = "ad5820",
.fops = &ad5820_fileops,
};
static int ad5820_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int err;
pr_info("ad5820: probing sensor.\n");
info = kzalloc(sizeof(struct ad5820_info), GFP_KERNEL);
if (!info) {
pr_err("ad5820: Unable to allocate memory!\n");
return -ENOMEM;
}
err = misc_register(&ad5820_device);
if (err) {
pr_err("ad5820: Unable to register misc device!\n");
kfree(info);
return err;
}
info->regulator = regulator_get(&client->dev, "vdd_vcore_af");
if (IS_ERR_OR_NULL(info->regulator)) {
dev_err(&client->dev, "unable to get regulator %s\n",
dev_name(&client->dev));
info->regulator = NULL;
} else {
regulator_enable(info->regulator);
}
info->i2c_client = client;
info->config.settle_time = SETTLETIME_MS;
info->config.focal_length = FOCAL_LENGTH;
info->config.fnumber = FNUMBER;
info->config.pos_low = POS_LOW;
info->config.pos_high = POS_HIGH;
i2c_set_clientdata(client, info);
return 0;
}
static int ad5820_remove(struct i2c_client *client)
{
struct ad5820_info *info;
info = i2c_get_clientdata(client);
misc_deregister(&ad5820_device);
kfree(info);
return 0;
}
static const struct i2c_device_id ad5820_id[] = {
{ "ad5820", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, ad5820_id);
static struct i2c_driver ad5820_i2c_driver = {
.driver = {
.name = "ad5820",
.owner = THIS_MODULE,
},
.probe = ad5820_probe,
.remove = ad5820_remove,
.id_table = ad5820_id,
};
static int __init ad5820_init(void)
{
pr_info("ad5820 sensor driver loading\n");
return i2c_add_driver(&ad5820_i2c_driver);
}
static void __exit ad5820_exit(void)
{
i2c_del_driver(&ad5820_i2c_driver);
}
module_init(ad5820_init);
module_exit(ad5820_exit);
MODULE_LICENSE("GPL v2");
|
