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-rw-r--r--drivers/i2c/chips/pcf8591.c325
1 files changed, 0 insertions, 325 deletions
diff --git a/drivers/i2c/chips/pcf8591.c b/drivers/i2c/chips/pcf8591.c
deleted file mode 100644
index 16ce3e193776..000000000000
--- a/drivers/i2c/chips/pcf8591.c
+++ /dev/null
@@ -1,325 +0,0 @@
1/*
2 Copyright (C) 2001-2004 Aurelien Jarno <aurelien@aurel32.net>
3 Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
4 the help of Jean Delvare <khali@linux-fr.org>
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19*/
20
21#include <linux/module.h>
22#include <linux/init.h>
23#include <linux/slab.h>
24#include <linux/i2c.h>
25#include <linux/mutex.h>
26
27/* Addresses to scan */
28static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
29 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
30
31/* Insmod parameters */
32I2C_CLIENT_INSMOD_1(pcf8591);
33
34static int input_mode;
35module_param(input_mode, int, 0);
36MODULE_PARM_DESC(input_mode,
37 "Analog input mode:\n"
38 " 0 = four single ended inputs\n"
39 " 1 = three differential inputs\n"
40 " 2 = single ended and differential mixed\n"
41 " 3 = two differential inputs\n");
42
43/* The PCF8591 control byte
44 7 6 5 4 3 2 1 0
45 | 0 |AOEF| AIP | 0 |AINC| AICH | */
46
47/* Analog Output Enable Flag (analog output active if 1) */
48#define PCF8591_CONTROL_AOEF 0x40
49
50/* Analog Input Programming
51 0x00 = four single ended inputs
52 0x10 = three differential inputs
53 0x20 = single ended and differential mixed
54 0x30 = two differential inputs */
55#define PCF8591_CONTROL_AIP_MASK 0x30
56
57/* Autoincrement Flag (switch on if 1) */
58#define PCF8591_CONTROL_AINC 0x04
59
60/* Channel selection
61 0x00 = channel 0
62 0x01 = channel 1
63 0x02 = channel 2
64 0x03 = channel 3 */
65#define PCF8591_CONTROL_AICH_MASK 0x03
66
67/* Initial values */
68#define PCF8591_INIT_CONTROL ((input_mode << 4) | PCF8591_CONTROL_AOEF)
69#define PCF8591_INIT_AOUT 0 /* DAC out = 0 */
70
71/* Conversions */
72#define REG_TO_SIGNED(reg) (((reg) & 0x80)?((reg) - 256):(reg))
73
74struct pcf8591_data {
75 struct mutex update_lock;
76
77 u8 control;
78 u8 aout;
79};
80
81static void pcf8591_init_client(struct i2c_client *client);
82static int pcf8591_read_channel(struct device *dev, int channel);
83
84/* following are the sysfs callback functions */
85#define show_in_channel(channel) \
86static ssize_t show_in##channel##_input(struct device *dev, struct device_attribute *attr, char *buf) \
87{ \
88 return sprintf(buf, "%d\n", pcf8591_read_channel(dev, channel));\
89} \
90static DEVICE_ATTR(in##channel##_input, S_IRUGO, \
91 show_in##channel##_input, NULL);
92
93show_in_channel(0);
94show_in_channel(1);
95show_in_channel(2);
96show_in_channel(3);
97
98static ssize_t show_out0_ouput(struct device *dev, struct device_attribute *attr, char *buf)
99{
100 struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
101 return sprintf(buf, "%d\n", data->aout * 10);
102}
103
104static ssize_t set_out0_output(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
105{
106 unsigned int value;
107 struct i2c_client *client = to_i2c_client(dev);
108 struct pcf8591_data *data = i2c_get_clientdata(client);
109 if ((value = (simple_strtoul(buf, NULL, 10) + 5) / 10) <= 255) {
110 data->aout = value;
111 i2c_smbus_write_byte_data(client, data->control, data->aout);
112 return count;
113 }
114 return -EINVAL;
115}
116
117static DEVICE_ATTR(out0_output, S_IWUSR | S_IRUGO,
118 show_out0_ouput, set_out0_output);
119
120static ssize_t show_out0_enable(struct device *dev, struct device_attribute *attr, char *buf)
121{
122 struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
123 return sprintf(buf, "%u\n", !(!(data->control & PCF8591_CONTROL_AOEF)));
124}
125
126static ssize_t set_out0_enable(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
127{
128 struct i2c_client *client = to_i2c_client(dev);
129 struct pcf8591_data *data = i2c_get_clientdata(client);
130 unsigned long val = simple_strtoul(buf, NULL, 10);
131
132 mutex_lock(&data->update_lock);
133 if (val)
134 data->control |= PCF8591_CONTROL_AOEF;
135 else
136 data->control &= ~PCF8591_CONTROL_AOEF;
137 i2c_smbus_write_byte(client, data->control);
138 mutex_unlock(&data->update_lock);
139 return count;
140}
141
142static DEVICE_ATTR(out0_enable, S_IWUSR | S_IRUGO,
143 show_out0_enable, set_out0_enable);
144
145static struct attribute *pcf8591_attributes[] = {
146 &dev_attr_out0_enable.attr,
147 &dev_attr_out0_output.attr,
148 &dev_attr_in0_input.attr,
149 &dev_attr_in1_input.attr,
150 NULL
151};
152
153static const struct attribute_group pcf8591_attr_group = {
154 .attrs = pcf8591_attributes,
155};
156
157static struct attribute *pcf8591_attributes_opt[] = {
158 &dev_attr_in2_input.attr,
159 &dev_attr_in3_input.attr,
160 NULL
161};
162
163static const struct attribute_group pcf8591_attr_group_opt = {
164 .attrs = pcf8591_attributes_opt,
165};
166
167/*
168 * Real code
169 */
170
171/* Return 0 if detection is successful, -ENODEV otherwise */
172static int pcf8591_detect(struct i2c_client *client, int kind,
173 struct i2c_board_info *info)
174{
175 struct i2c_adapter *adapter = client->adapter;
176
177 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE
178 | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
179 return -ENODEV;
180
181 /* Now, we would do the remaining detection. But the PCF8591 is plainly
182 impossible to detect! Stupid chip. */
183
184 strlcpy(info->type, "pcf8591", I2C_NAME_SIZE);
185
186 return 0;
187}
188
189static int pcf8591_probe(struct i2c_client *client,
190 const struct i2c_device_id *id)
191{
192 struct pcf8591_data *data;
193 int err;
194
195 if (!(data = kzalloc(sizeof(struct pcf8591_data), GFP_KERNEL))) {
196 err = -ENOMEM;
197 goto exit;
198 }
199
200 i2c_set_clientdata(client, data);
201 mutex_init(&data->update_lock);
202
203 /* Initialize the PCF8591 chip */
204 pcf8591_init_client(client);
205
206 /* Register sysfs hooks */
207 err = sysfs_create_group(&client->dev.kobj, &pcf8591_attr_group);
208 if (err)
209 goto exit_kfree;
210
211 /* Register input2 if not in "two differential inputs" mode */
212 if (input_mode != 3) {
213 if ((err = device_create_file(&client->dev,
214 &dev_attr_in2_input)))
215 goto exit_sysfs_remove;
216 }
217
218 /* Register input3 only in "four single ended inputs" mode */
219 if (input_mode == 0) {
220 if ((err = device_create_file(&client->dev,
221 &dev_attr_in3_input)))
222 goto exit_sysfs_remove;
223 }
224
225 return 0;
226
227exit_sysfs_remove:
228 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
229 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
230exit_kfree:
231 kfree(data);
232exit:
233 return err;
234}
235
236static int pcf8591_remove(struct i2c_client *client)
237{
238 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
239 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
240 kfree(i2c_get_clientdata(client));
241 return 0;
242}
243
244/* Called when we have found a new PCF8591. */
245static void pcf8591_init_client(struct i2c_client *client)
246{
247 struct pcf8591_data *data = i2c_get_clientdata(client);
248 data->control = PCF8591_INIT_CONTROL;
249 data->aout = PCF8591_INIT_AOUT;
250
251 i2c_smbus_write_byte_data(client, data->control, data->aout);
252
253 /* The first byte transmitted contains the conversion code of the
254 previous read cycle. FLUSH IT! */
255 i2c_smbus_read_byte(client);
256}
257
258static int pcf8591_read_channel(struct device *dev, int channel)
259{
260 u8 value;
261 struct i2c_client *client = to_i2c_client(dev);
262 struct pcf8591_data *data = i2c_get_clientdata(client);
263
264 mutex_lock(&data->update_lock);
265
266 if ((data->control & PCF8591_CONTROL_AICH_MASK) != channel) {
267 data->control = (data->control & ~PCF8591_CONTROL_AICH_MASK)
268 | channel;
269 i2c_smbus_write_byte(client, data->control);
270
271 /* The first byte transmitted contains the conversion code of
272 the previous read cycle. FLUSH IT! */
273 i2c_smbus_read_byte(client);
274 }
275 value = i2c_smbus_read_byte(client);
276
277 mutex_unlock(&data->update_lock);
278
279 if ((channel == 2 && input_mode == 2) ||
280 (channel != 3 && (input_mode == 1 || input_mode == 3)))
281 return (10 * REG_TO_SIGNED(value));
282 else
283 return (10 * value);
284}
285
286static const struct i2c_device_id pcf8591_id[] = {
287 { "pcf8591", 0 },
288 { }
289};
290MODULE_DEVICE_TABLE(i2c, pcf8591_id);
291
292static struct i2c_driver pcf8591_driver = {
293 .driver = {
294 .name = "pcf8591",
295 },
296 .probe = pcf8591_probe,
297 .remove = pcf8591_remove,
298 .id_table = pcf8591_id,
299
300 .class = I2C_CLASS_HWMON, /* Nearest choice */
301 .detect = pcf8591_detect,
302 .address_data = &addr_data,
303};
304
305static int __init pcf8591_init(void)
306{
307 if (input_mode < 0 || input_mode > 3) {
308 printk(KERN_WARNING "pcf8591: invalid input_mode (%d)\n",
309 input_mode);
310 input_mode = 0;
311 }
312 return i2c_add_driver(&pcf8591_driver);
313}
314
315static void __exit pcf8591_exit(void)
316{
317 i2c_del_driver(&pcf8591_driver);
318}
319
320MODULE_AUTHOR("Aurelien Jarno <aurelien@aurel32.net>");
321MODULE_DESCRIPTION("PCF8591 driver");
322MODULE_LICENSE("GPL");
323
324module_init(pcf8591_init);
325module_exit(pcf8591_exit);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-22 11:26:20 -0500