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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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/slab.h>
26#include <linux/i2c.h>
27#include <linux/mutex.h>
28#include <linux/err.h>
29#include <linux/hwmon.h>
30
31/* Insmod parameters */
32
33static int input_mode;
34module_param(input_mode, int, 0);
35MODULE_PARM_DESC(input_mode,
36 "Analog input mode:\n"
37 " 0 = four single ended inputs\n"
38 " 1 = three differential inputs\n"
39 " 2 = single ended and differential mixed\n"
40 " 3 = two differential inputs\n");
41
42/* The PCF8591 control byte
43 7 6 5 4 3 2 1 0
44 | 0 |AOEF| AIP | 0 |AINC| AICH | */
45
46/* Analog Output Enable Flag (analog output active if 1) */
47#define PCF8591_CONTROL_AOEF 0x40
48
49/* Analog Input Programming
50 0x00 = four single ended inputs
51 0x10 = three differential inputs
52 0x20 = single ended and differential mixed
53 0x30 = two differential inputs */
54#define PCF8591_CONTROL_AIP_MASK 0x30
55
56/* Autoincrement Flag (switch on if 1) */
57#define PCF8591_CONTROL_AINC 0x04
58
59/* Channel selection
60 0x00 = channel 0
61 0x01 = channel 1
62 0x02 = channel 2
63 0x03 = channel 3 */
64#define PCF8591_CONTROL_AICH_MASK 0x03
65
66/* Initial values */
67#define PCF8591_INIT_CONTROL ((input_mode << 4) | PCF8591_CONTROL_AOEF)
68#define PCF8591_INIT_AOUT 0 /* DAC out = 0 */
69
70/* Conversions */
71#define REG_TO_SIGNED(reg) (((reg) & 0x80)?((reg) - 256):(reg))
72
73struct pcf8591_data {
74 struct device *hwmon_dev;
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
171static int pcf8591_probe(struct i2c_client *client,
172 const struct i2c_device_id *id)
173{
174 struct pcf8591_data *data;
175 int err;
176
177 if (!(data = kzalloc(sizeof(struct pcf8591_data), GFP_KERNEL))) {
178 err = -ENOMEM;
179 goto exit;
180 }
181
182 i2c_set_clientdata(client, data);
183 mutex_init(&data->update_lock);
184
185 /* Initialize the PCF8591 chip */
186 pcf8591_init_client(client);
187
188 /* Register sysfs hooks */
189 err = sysfs_create_group(&client->dev.kobj, &pcf8591_attr_group);
190 if (err)
191 goto exit_kfree;
192
193 /* Register input2 if not in "two differential inputs" mode */
194 if (input_mode != 3) {
195 if ((err = device_create_file(&client->dev,
196 &dev_attr_in2_input)))
197 goto exit_sysfs_remove;
198 }
199
200 /* Register input3 only in "four single ended inputs" mode */
201 if (input_mode == 0) {
202 if ((err = device_create_file(&client->dev,
203 &dev_attr_in3_input)))
204 goto exit_sysfs_remove;
205 }
206
207 data->hwmon_dev = hwmon_device_register(&client->dev);
208 if (IS_ERR(data->hwmon_dev)) {
209 err = PTR_ERR(data->hwmon_dev);
210 goto exit_sysfs_remove;
211 }
212
213 return 0;
214
215exit_sysfs_remove:
216 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
217 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
218exit_kfree:
219 kfree(data);
220exit:
221 return err;
222}
223
224static int pcf8591_remove(struct i2c_client *client)
225{
226 struct pcf8591_data *data = i2c_get_clientdata(client);
227
228 hwmon_device_unregister(data->hwmon_dev);
229 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
230 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
231 kfree(i2c_get_clientdata(client));
232 return 0;
233}
234
235/* Called when we have found a new PCF8591. */
236static void pcf8591_init_client(struct i2c_client *client)
237{
238 struct pcf8591_data *data = i2c_get_clientdata(client);
239 data->control = PCF8591_INIT_CONTROL;
240 data->aout = PCF8591_INIT_AOUT;
241
242 i2c_smbus_write_byte_data(client, data->control, data->aout);
243
244 /* The first byte transmitted contains the conversion code of the
245 previous read cycle. FLUSH IT! */
246 i2c_smbus_read_byte(client);
247}
248
249static int pcf8591_read_channel(struct device *dev, int channel)
250{
251 u8 value;
252 struct i2c_client *client = to_i2c_client(dev);
253 struct pcf8591_data *data = i2c_get_clientdata(client);
254
255 mutex_lock(&data->update_lock);
256
257 if ((data->control & PCF8591_CONTROL_AICH_MASK) != channel) {
258 data->control = (data->control & ~PCF8591_CONTROL_AICH_MASK)
259 | channel;
260 i2c_smbus_write_byte(client, data->control);
261
262 /* The first byte transmitted contains the conversion code of
263 the previous read cycle. FLUSH IT! */
264 i2c_smbus_read_byte(client);
265 }
266 value = i2c_smbus_read_byte(client);
267
268 mutex_unlock(&data->update_lock);
269
270 if ((channel == 2 && input_mode == 2) ||
271 (channel != 3 && (input_mode == 1 || input_mode == 3)))
272 return (10 * REG_TO_SIGNED(value));
273 else
274 return (10 * value);
275}
276
277static const struct i2c_device_id pcf8591_id[] = {
278 { "pcf8591", 0 },
279 { }
280};
281MODULE_DEVICE_TABLE(i2c, pcf8591_id);
282
283static struct i2c_driver pcf8591_driver = {
284 .driver = {
285 .name = "pcf8591",
286 },
287 .probe = pcf8591_probe,
288 .remove = pcf8591_remove,
289 .id_table = pcf8591_id,
290};
291
292static int __init pcf8591_init(void)
293{
294 if (input_mode < 0 || input_mode > 3) {
295 pr_warn("invalid input_mode (%d)\n", input_mode);
296 input_mode = 0;
297 }
298 return i2c_add_driver(&pcf8591_driver);
299}
300
301static void __exit pcf8591_exit(void)
302{
303 i2c_del_driver(&pcf8591_driver);
304}
305
306MODULE_AUTHOR("Aurelien Jarno <aurelien@aurel32.net>");
307MODULE_DESCRIPTION("PCF8591 driver");
308MODULE_LICENSE("GPL");
309
310module_init(pcf8591_init);
311module_exit(pcf8591_exit);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2001-2004 Aurelien Jarno <aurelien@aurel32.net>
4 * Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
5 * the help of Jean Delvare <jdelvare@suse.de>
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/slab.h>
13#include <linux/i2c.h>
14#include <linux/mutex.h>
15#include <linux/err.h>
16#include <linux/hwmon.h>
17
18/* Insmod parameters */
19
20static int input_mode;
21module_param(input_mode, int, 0);
22MODULE_PARM_DESC(input_mode,
23 "Analog input mode:\n"
24 " 0 = four single ended inputs\n"
25 " 1 = three differential inputs\n"
26 " 2 = single ended and differential mixed\n"
27 " 3 = two differential inputs\n");
28
29/*
30 * The PCF8591 control byte
31 * 7 6 5 4 3 2 1 0
32 * | 0 |AOEF| AIP | 0 |AINC| AICH |
33 */
34
35/* Analog Output Enable Flag (analog output active if 1) */
36#define PCF8591_CONTROL_AOEF 0x40
37
38/*
39 * Analog Input Programming
40 * 0x00 = four single ended inputs
41 * 0x10 = three differential inputs
42 * 0x20 = single ended and differential mixed
43 * 0x30 = two differential inputs
44 */
45#define PCF8591_CONTROL_AIP_MASK 0x30
46
47/* Autoincrement Flag (switch on if 1) */
48#define PCF8591_CONTROL_AINC 0x04
49
50/*
51 * Channel selection
52 * 0x00 = channel 0
53 * 0x01 = channel 1
54 * 0x02 = channel 2
55 * 0x03 = channel 3
56 */
57#define PCF8591_CONTROL_AICH_MASK 0x03
58
59/* Initial values */
60#define PCF8591_INIT_CONTROL ((input_mode << 4) | PCF8591_CONTROL_AOEF)
61#define PCF8591_INIT_AOUT 0 /* DAC out = 0 */
62
63/* Conversions */
64#define REG_TO_SIGNED(reg) (((reg) & 0x80) ? ((reg) - 256) : (reg))
65
66struct pcf8591_data {
67 struct device *hwmon_dev;
68 struct mutex update_lock;
69
70 u8 control;
71 u8 aout;
72};
73
74static void pcf8591_init_client(struct i2c_client *client);
75static int pcf8591_read_channel(struct device *dev, int channel);
76
77/* following are the sysfs callback functions */
78#define show_in_channel(channel) \
79static ssize_t show_in##channel##_input(struct device *dev, \
80 struct device_attribute *attr, \
81 char *buf) \
82{ \
83 return sprintf(buf, "%d\n", pcf8591_read_channel(dev, channel));\
84} \
85static DEVICE_ATTR(in##channel##_input, S_IRUGO, \
86 show_in##channel##_input, NULL);
87
88show_in_channel(0);
89show_in_channel(1);
90show_in_channel(2);
91show_in_channel(3);
92
93static ssize_t out0_output_show(struct device *dev,
94 struct device_attribute *attr, char *buf)
95{
96 struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
97 return sprintf(buf, "%d\n", data->aout * 10);
98}
99
100static ssize_t out0_output_store(struct device *dev,
101 struct device_attribute *attr,
102 const char *buf, size_t count)
103{
104 unsigned long val;
105 struct i2c_client *client = to_i2c_client(dev);
106 struct pcf8591_data *data = i2c_get_clientdata(client);
107 int err;
108
109 err = kstrtoul(buf, 10, &val);
110 if (err)
111 return err;
112
113 val /= 10;
114 if (val > 255)
115 return -EINVAL;
116
117 data->aout = val;
118 i2c_smbus_write_byte_data(client, data->control, data->aout);
119 return count;
120}
121
122static DEVICE_ATTR_RW(out0_output);
123
124static ssize_t out0_enable_show(struct device *dev,
125 struct device_attribute *attr, char *buf)
126{
127 struct pcf8591_data *data = i2c_get_clientdata(to_i2c_client(dev));
128 return sprintf(buf, "%u\n", !(!(data->control & PCF8591_CONTROL_AOEF)));
129}
130
131static ssize_t out0_enable_store(struct device *dev,
132 struct device_attribute *attr,
133 const char *buf, size_t count)
134{
135 struct i2c_client *client = to_i2c_client(dev);
136 struct pcf8591_data *data = i2c_get_clientdata(client);
137 unsigned long val;
138 int err;
139
140 err = kstrtoul(buf, 10, &val);
141 if (err)
142 return err;
143
144 mutex_lock(&data->update_lock);
145 if (val)
146 data->control |= PCF8591_CONTROL_AOEF;
147 else
148 data->control &= ~PCF8591_CONTROL_AOEF;
149 i2c_smbus_write_byte(client, data->control);
150 mutex_unlock(&data->update_lock);
151 return count;
152}
153
154static DEVICE_ATTR_RW(out0_enable);
155
156static struct attribute *pcf8591_attributes[] = {
157 &dev_attr_out0_enable.attr,
158 &dev_attr_out0_output.attr,
159 &dev_attr_in0_input.attr,
160 &dev_attr_in1_input.attr,
161 NULL
162};
163
164static const struct attribute_group pcf8591_attr_group = {
165 .attrs = pcf8591_attributes,
166};
167
168static struct attribute *pcf8591_attributes_opt[] = {
169 &dev_attr_in2_input.attr,
170 &dev_attr_in3_input.attr,
171 NULL
172};
173
174static const struct attribute_group pcf8591_attr_group_opt = {
175 .attrs = pcf8591_attributes_opt,
176};
177
178/*
179 * Real code
180 */
181
182static int pcf8591_probe(struct i2c_client *client,
183 const struct i2c_device_id *id)
184{
185 struct pcf8591_data *data;
186 int err;
187
188 data = devm_kzalloc(&client->dev, sizeof(struct pcf8591_data),
189 GFP_KERNEL);
190 if (!data)
191 return -ENOMEM;
192
193 i2c_set_clientdata(client, data);
194 mutex_init(&data->update_lock);
195
196 /* Initialize the PCF8591 chip */
197 pcf8591_init_client(client);
198
199 /* Register sysfs hooks */
200 err = sysfs_create_group(&client->dev.kobj, &pcf8591_attr_group);
201 if (err)
202 return err;
203
204 /* Register input2 if not in "two differential inputs" mode */
205 if (input_mode != 3) {
206 err = device_create_file(&client->dev, &dev_attr_in2_input);
207 if (err)
208 goto exit_sysfs_remove;
209 }
210
211 /* Register input3 only in "four single ended inputs" mode */
212 if (input_mode == 0) {
213 err = device_create_file(&client->dev, &dev_attr_in3_input);
214 if (err)
215 goto exit_sysfs_remove;
216 }
217
218 data->hwmon_dev = hwmon_device_register(&client->dev);
219 if (IS_ERR(data->hwmon_dev)) {
220 err = PTR_ERR(data->hwmon_dev);
221 goto exit_sysfs_remove;
222 }
223
224 return 0;
225
226exit_sysfs_remove:
227 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
228 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
229 return err;
230}
231
232static int pcf8591_remove(struct i2c_client *client)
233{
234 struct pcf8591_data *data = i2c_get_clientdata(client);
235
236 hwmon_device_unregister(data->hwmon_dev);
237 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
238 sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
239 return 0;
240}
241
242/* Called when we have found a new PCF8591. */
243static void pcf8591_init_client(struct i2c_client *client)
244{
245 struct pcf8591_data *data = i2c_get_clientdata(client);
246 data->control = PCF8591_INIT_CONTROL;
247 data->aout = PCF8591_INIT_AOUT;
248
249 i2c_smbus_write_byte_data(client, data->control, data->aout);
250
251 /*
252 * The first byte transmitted contains the conversion code of the
253 * previous read cycle. FLUSH IT!
254 */
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 /*
272 * The first byte transmitted contains the conversion code of
273 * the previous read cycle. FLUSH IT!
274 */
275 i2c_smbus_read_byte(client);
276 }
277 value = i2c_smbus_read_byte(client);
278
279 mutex_unlock(&data->update_lock);
280
281 if ((channel == 2 && input_mode == 2) ||
282 (channel != 3 && (input_mode == 1 || input_mode == 3)))
283 return 10 * REG_TO_SIGNED(value);
284 else
285 return 10 * value;
286}
287
288static const struct i2c_device_id pcf8591_id[] = {
289 { "pcf8591", 0 },
290 { }
291};
292MODULE_DEVICE_TABLE(i2c, pcf8591_id);
293
294static struct i2c_driver pcf8591_driver = {
295 .driver = {
296 .name = "pcf8591",
297 },
298 .probe = pcf8591_probe,
299 .remove = pcf8591_remove,
300 .id_table = pcf8591_id,
301};
302
303static int __init pcf8591_init(void)
304{
305 if (input_mode < 0 || input_mode > 3) {
306 pr_warn("invalid input_mode (%d)\n", input_mode);
307 input_mode = 0;
308 }
309 return i2c_add_driver(&pcf8591_driver);
310}
311
312static void __exit pcf8591_exit(void)
313{
314 i2c_del_driver(&pcf8591_driver);
315}
316
317MODULE_AUTHOR("Aurelien Jarno <aurelien@aurel32.net>");
318MODULE_DESCRIPTION("PCF8591 driver");
319MODULE_LICENSE("GPL");
320
321module_init(pcf8591_init);
322module_exit(pcf8591_exit);