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
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* 1-Wire implementation for the ds2781 chip
*
* Author: Renata Sayakhova <renata@oktetlabs.ru>
*
* Based on w1-ds2780 driver
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/types.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/w1.h>
#include "w1_ds2781.h"
#define W1_FAMILY_DS2781 0x3D
static int w1_ds2781_do_io(struct device *dev, char *buf, int addr,
size_t count, int io)
{
struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
if (addr > DS2781_DATA_SIZE || addr < 0)
return 0;
count = min_t(int, count, DS2781_DATA_SIZE - addr);
if (w1_reset_select_slave(sl) == 0) {
if (io) {
w1_write_8(sl->master, W1_DS2781_WRITE_DATA);
w1_write_8(sl->master, addr);
w1_write_block(sl->master, buf, count);
} else {
w1_write_8(sl->master, W1_DS2781_READ_DATA);
w1_write_8(sl->master, addr);
count = w1_read_block(sl->master, buf, count);
}
}
return count;
}
int w1_ds2781_io(struct device *dev, char *buf, int addr, size_t count,
int io)
{
struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
int ret;
if (!dev)
return -ENODEV;
mutex_lock(&sl->master->bus_mutex);
ret = w1_ds2781_do_io(dev, buf, addr, count, io);
mutex_unlock(&sl->master->bus_mutex);
return ret;
}
EXPORT_SYMBOL(w1_ds2781_io);
int w1_ds2781_eeprom_cmd(struct device *dev, int addr, int cmd)
{
struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
if (!dev)
return -EINVAL;
mutex_lock(&sl->master->bus_mutex);
if (w1_reset_select_slave(sl) == 0) {
w1_write_8(sl->master, cmd);
w1_write_8(sl->master, addr);
}
mutex_unlock(&sl->master->bus_mutex);
return 0;
}
EXPORT_SYMBOL(w1_ds2781_eeprom_cmd);
static ssize_t w1_slave_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr, char *buf,
loff_t off, size_t count)
{
struct device *dev = kobj_to_dev(kobj);
return w1_ds2781_io(dev, buf, off, count, 0);
}
static BIN_ATTR_RO(w1_slave, DS2781_DATA_SIZE);
static struct bin_attribute *w1_ds2781_bin_attrs[] = {
&bin_attr_w1_slave,
NULL,
};
static const struct attribute_group w1_ds2781_group = {
.bin_attrs = w1_ds2781_bin_attrs,
};
static const struct attribute_group *w1_ds2781_groups[] = {
&w1_ds2781_group,
NULL,
};
static int w1_ds2781_add_slave(struct w1_slave *sl)
{
int ret;
struct platform_device *pdev;
pdev = platform_device_alloc("ds2781-battery", PLATFORM_DEVID_AUTO);
if (!pdev)
return -ENOMEM;
pdev->dev.parent = &sl->dev;
ret = platform_device_add(pdev);
if (ret)
goto pdev_add_failed;
dev_set_drvdata(&sl->dev, pdev);
return 0;
pdev_add_failed:
platform_device_put(pdev);
return ret;
}
static void w1_ds2781_remove_slave(struct w1_slave *sl)
{
struct platform_device *pdev = dev_get_drvdata(&sl->dev);
platform_device_unregister(pdev);
}
static const struct w1_family_ops w1_ds2781_fops = {
.add_slave = w1_ds2781_add_slave,
.remove_slave = w1_ds2781_remove_slave,
.groups = w1_ds2781_groups,
};
static struct w1_family w1_ds2781_family = {
.fid = W1_FAMILY_DS2781,
.fops = &w1_ds2781_fops,
};
module_w1_family(w1_ds2781_family);
MODULE_AUTHOR("Renata Sayakhova <renata@oktetlabs.ru>");
MODULE_DESCRIPTION("1-wire Driver for Maxim/Dallas DS2781 Stand-Alone Fuel Gauge IC");
MODULE_LICENSE("GPL");
MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2781));
|
