summaryrefslogtreecommitdiffstats
path: root/drivers/w1/slaves/w1_ds2760.c
blob: e86a69dc411e5ddbd150d1a1cd8799809c567b51 (plain)
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
/*
 * 1-Wire implementation for the ds2760 chip
 *
 * Copyright © 2004-2005, Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
 *
 * Use consistent with the GNU GPL is permitted,
 * provided that this copyright notice is
 * preserved in its entirety in all copies and derived works.
 *
 */

#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/idr.h>
#include <linux/gfp.h>

#include "../w1.h"
#include "../w1_int.h"
#include "../w1_family.h"
#include "w1_ds2760.h"

static int w1_ds2760_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 (!dev)
		return 0;

	mutex_lock(&sl->master->bus_mutex);

	if (addr > DS2760_DATA_SIZE || addr < 0) {
		count = 0;
		goto out;
	}
	if (addr + count > DS2760_DATA_SIZE)
		count = DS2760_DATA_SIZE - addr;

	if (!w1_reset_select_slave(sl)) {
		if (!io) {
			w1_write_8(sl->master, W1_DS2760_READ_DATA);
			w1_write_8(sl->master, addr);
			count = w1_read_block(sl->master, buf, count);
		} else {
			w1_write_8(sl->master, W1_DS2760_WRITE_DATA);
			w1_write_8(sl->master, addr);
			w1_write_block(sl->master, buf, count);
			/* XXX w1_write_block returns void, not n_written */
		}
	}

out:
	mutex_unlock(&sl->master->bus_mutex);

	return count;
}

int w1_ds2760_read(struct device *dev, char *buf, int addr, size_t count)
{
	return w1_ds2760_io(dev, buf, addr, count, 0);
}

int w1_ds2760_write(struct device *dev, char *buf, int addr, size_t count)
{
	return w1_ds2760_io(dev, buf, addr, count, 1);
}

static int w1_ds2760_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;
}

int w1_ds2760_store_eeprom(struct device *dev, int addr)
{
	return w1_ds2760_eeprom_cmd(dev, addr, W1_DS2760_COPY_DATA);
}

int w1_ds2760_recall_eeprom(struct device *dev, int addr)
{
	return w1_ds2760_eeprom_cmd(dev, addr, W1_DS2760_RECALL_DATA);
}

static ssize_t w1_ds2760_read_bin(struct file *filp, struct kobject *kobj,
				  struct bin_attribute *bin_attr,
				  char *buf, loff_t off, size_t count)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	return w1_ds2760_read(dev, buf, off, count);
}

static struct bin_attribute w1_ds2760_bin_attr = {
	.attr = {
		.name = "w1_slave",
		.mode = S_IRUGO,
	},
	.size = DS2760_DATA_SIZE,
	.read = w1_ds2760_read_bin,
};

static DEFINE_IDA(bat_ida);

static int w1_ds2760_add_slave(struct w1_slave *sl)
{
	int ret;
	int id;
	struct platform_device *pdev;

	id = ida_simple_get(&bat_ida, 0, 0, GFP_KERNEL);
	if (id < 0) {
		ret = id;
		goto noid;
	}

	pdev = platform_device_alloc("ds2760-battery", id);
	if (!pdev) {
		ret = -ENOMEM;
		goto pdev_alloc_failed;
	}
	pdev->dev.parent = &sl->dev;

	ret = platform_device_add(pdev);
	if (ret)
		goto pdev_add_failed;

	ret = sysfs_create_bin_file(&sl->dev.kobj, &w1_ds2760_bin_attr);
	if (ret)
		goto bin_attr_failed;

	dev_set_drvdata(&sl->dev, pdev);

	goto success;

bin_attr_failed:
	platform_device_del(pdev);
pdev_add_failed:
	platform_device_put(pdev);
pdev_alloc_failed:
	ida_simple_remove(&bat_ida, id);
noid:
success:
	return ret;
}

static void w1_ds2760_remove_slave(struct w1_slave *sl)
{
	struct platform_device *pdev = dev_get_drvdata(&sl->dev);
	int id = pdev->id;

	platform_device_unregister(pdev);
	ida_simple_remove(&bat_ida, id);
	sysfs_remove_bin_file(&sl->dev.kobj, &w1_ds2760_bin_attr);
}

static struct w1_family_ops w1_ds2760_fops = {
	.add_slave    = w1_ds2760_add_slave,
	.remove_slave = w1_ds2760_remove_slave,
};

static struct w1_family w1_ds2760_family = {
	.fid = W1_FAMILY_DS2760,
	.fops = &w1_ds2760_fops,
};

static int __init w1_ds2760_init(void)
{
	printk(KERN_INFO "1-Wire driver for the DS2760 battery monitor "
	       " chip  - (c) 2004-2005, Szabolcs Gyurko\n");
	ida_init(&bat_ida);
	return w1_register_family(&w1_ds2760_family);
}

static void __exit w1_ds2760_exit(void)
{
	w1_unregister_family(&w1_ds2760_family);
	ida_destroy(&bat_ida);
}

EXPORT_SYMBOL(w1_ds2760_read);
EXPORT_SYMBOL(w1_ds2760_write);
EXPORT_SYMBOL(w1_ds2760_store_eeprom);
EXPORT_SYMBOL(w1_ds2760_recall_eeprom);

module_init(w1_ds2760_init);
module_exit(w1_ds2760_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>");
MODULE_DESCRIPTION("1-wire Driver Dallas 2760 battery monitor chip");
OpenPOWER on IntegriCloud