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Diffstat (limited to 'drivers/i2c/chips/pcf8575.c')
-rw-r--r--drivers/i2c/chips/pcf8575.c198
1 files changed, 0 insertions, 198 deletions
diff --git a/drivers/i2c/chips/pcf8575.c b/drivers/i2c/chips/pcf8575.c
deleted file mode 100644
index 07fd7cb3c57d..000000000000
--- a/drivers/i2c/chips/pcf8575.c
+++ /dev/null
@@ -1,198 +0,0 @@
1/*
2 pcf8575.c
3
4 About the PCF8575 chip: the PCF8575 is a 16-bit I/O expander for the I2C bus
5 produced by a.o. Philips Semiconductors.
6
7 Copyright (C) 2006 Michael Hennerich, Analog Devices Inc.
8 <hennerich@blackfin.uclinux.org>
9 Based on pcf8574.c.
10
11 Copyright (c) 2007 Bart Van Assche <bart.vanassche@gmail.com>.
12 Ported this driver from ucLinux to the mainstream Linux kernel.
13
14 This program is free software; you can redistribute it and/or modify
15 it under the terms of the GNU General Public License as published by
16 the Free Software Foundation; either version 2 of the License, or
17 (at your option) any later version.
18
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 GNU General Public License for more details.
23
24 You should have received a copy of the GNU General Public License
25 along with this program; if not, write to the Free Software
26 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27*/
28
29#include <linux/module.h>
30#include <linux/init.h>
31#include <linux/i2c.h>
32#include <linux/slab.h> /* kzalloc() */
33#include <linux/sysfs.h> /* sysfs_create_group() */
34
35/* Addresses to scan: none, device can't be detected */
36static const unsigned short normal_i2c[] = { I2C_CLIENT_END };
37
38/* Insmod parameters */
39I2C_CLIENT_INSMOD;
40
41
42/* Each client has this additional data */
43struct pcf8575_data {
44 int write; /* last written value, or error code */
45};
46
47/* following are the sysfs callback functions */
48static ssize_t show_read(struct device *dev, struct device_attribute *attr,
49 char *buf)
50{
51 struct i2c_client *client = to_i2c_client(dev);
52 u16 val;
53 u8 iopin_state[2];
54
55 i2c_master_recv(client, iopin_state, 2);
56
57 val = iopin_state[0];
58 val |= iopin_state[1] << 8;
59
60 return sprintf(buf, "%u\n", val);
61}
62
63static DEVICE_ATTR(read, S_IRUGO, show_read, NULL);
64
65static ssize_t show_write(struct device *dev, struct device_attribute *attr,
66 char *buf)
67{
68 struct pcf8575_data *data = dev_get_drvdata(dev);
69 if (data->write < 0)
70 return data->write;
71 return sprintf(buf, "%d\n", data->write);
72}
73
74static ssize_t set_write(struct device *dev, struct device_attribute *attr,
75 const char *buf, size_t count)
76{
77 struct i2c_client *client = to_i2c_client(dev);
78 struct pcf8575_data *data = i2c_get_clientdata(client);
79 unsigned long val = simple_strtoul(buf, NULL, 10);
80 u8 iopin_state[2];
81
82 if (val > 0xffff)
83 return -EINVAL;
84
85 data->write = val;
86
87 iopin_state[0] = val & 0xFF;
88 iopin_state[1] = val >> 8;
89
90 i2c_master_send(client, iopin_state, 2);
91
92 return count;
93}
94
95static DEVICE_ATTR(write, S_IWUSR | S_IRUGO, show_write, set_write);
96
97static struct attribute *pcf8575_attributes[] = {
98 &dev_attr_read.attr,
99 &dev_attr_write.attr,
100 NULL
101};
102
103static const struct attribute_group pcf8575_attr_group = {
104 .attrs = pcf8575_attributes,
105};
106
107/*
108 * Real code
109 */
110
111/* Return 0 if detection is successful, -ENODEV otherwise */
112static int pcf8575_detect(struct i2c_client *client, int kind,
113 struct i2c_board_info *info)
114{
115 struct i2c_adapter *adapter = client->adapter;
116
117 if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
118 return -ENODEV;
119
120 /* This is the place to detect whether the chip at the specified
121 address really is a PCF8575 chip. However, there is no method known
122 to detect whether an I2C chip is a PCF8575 or any other I2C chip. */
123
124 strlcpy(info->type, "pcf8575", I2C_NAME_SIZE);
125
126 return 0;
127}
128
129static int pcf8575_probe(struct i2c_client *client,
130 const struct i2c_device_id *id)
131{
132 struct pcf8575_data *data;
133 int err;
134
135 data = kzalloc(sizeof(struct pcf8575_data), GFP_KERNEL);
136 if (!data) {
137 err = -ENOMEM;
138 goto exit;
139 }
140
141 i2c_set_clientdata(client, data);
142 data->write = -EAGAIN;
143
144 /* Register sysfs hooks */
145 err = sysfs_create_group(&client->dev.kobj, &pcf8575_attr_group);
146 if (err)
147 goto exit_free;
148
149 return 0;
150
151exit_free:
152 kfree(data);
153exit:
154 return err;
155}
156
157static int pcf8575_remove(struct i2c_client *client)
158{
159 sysfs_remove_group(&client->dev.kobj, &pcf8575_attr_group);
160 kfree(i2c_get_clientdata(client));
161 return 0;
162}
163
164static const struct i2c_device_id pcf8575_id[] = {
165 { "pcf8575", 0 },
166 { }
167};
168
169static struct i2c_driver pcf8575_driver = {
170 .driver = {
171 .owner = THIS_MODULE,
172 .name = "pcf8575",
173 },
174 .probe = pcf8575_probe,
175 .remove = pcf8575_remove,
176 .id_table = pcf8575_id,
177
178 .detect = pcf8575_detect,
179 .address_data = &addr_data,
180};
181
182static int __init pcf8575_init(void)
183{
184 return i2c_add_driver(&pcf8575_driver);
185}
186
187static void __exit pcf8575_exit(void)
188{
189 i2c_del_driver(&pcf8575_driver);
190}
191
192MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>, "
193 "Bart Van Assche <bart.vanassche@gmail.com>");
194MODULE_DESCRIPTION("pcf8575 driver");
195MODULE_LICENSE("GPL");
196
197module_init(pcf8575_init);
198module_exit(pcf8575_exit);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-13 10:13:43 -0500