1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * An hwmon driver for the Analog Devices AD7416/17/18
4 * Copyright (C) 2006-07 Tower Technologies
5 *
6 * Author: Alessandro Zummo <a.zummo@towertech.it>
7 *
8 * Based on lm75.c
9 * Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
10 */
11
12 #include <linux/module.h>
13 #include <linux/jiffies.h>
14 #include <linux/i2c.h>
15 #include <linux/hwmon.h>
16 #include <linux/hwmon-sysfs.h>
17 #include <linux/err.h>
18 #include <linux/mutex.h>
19 #include <linux/of.h>
20 #include <linux/delay.h>
21 #include <linux/slab.h>
22
23 #include "lm75.h"
24
25 #define DRV_VERSION "0.4"
26
27 enum chips { ad7416, ad7417, ad7418 };
28
29 /* AD7418 registers */
30 #define AD7418_REG_TEMP_IN 0x00
31 #define AD7418_REG_CONF 0x01
32 #define AD7418_REG_TEMP_HYST 0x02
33 #define AD7418_REG_TEMP_OS 0x03
34 #define AD7418_REG_ADC 0x04
35 #define AD7418_REG_CONF2 0x05
36
37 #define AD7418_REG_ADC_CH(x) ((x) << 5)
38 #define AD7418_CH_TEMP AD7418_REG_ADC_CH(0)
39
40 static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN,
41 AD7418_REG_TEMP_HYST,
42 AD7418_REG_TEMP_OS };
43
44 struct ad7418_data {
45 struct i2c_client *client;
46 enum chips type;
47 struct mutex lock;
48 int adc_max; /* number of ADC channels */
49 bool valid;
50 unsigned long last_updated; /* In jiffies */
51 s16 temp[3]; /* Register values */
52 u16 in[4];
53 };
54
ad7418_update_device(struct device * dev)55 static int ad7418_update_device(struct device *dev)
56 {
57 struct ad7418_data *data = dev_get_drvdata(dev);
58 struct i2c_client *client = data->client;
59 s32 val;
60
61 mutex_lock(&data->lock);
62
63 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
64 || !data->valid) {
65 u8 cfg;
66 int i, ch;
67
68 /* read config register and clear channel bits */
69 val = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
70 if (val < 0)
71 goto abort;
72
73 cfg = val;
74 cfg &= 0x1F;
75
76 val = i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
77 cfg | AD7418_CH_TEMP);
78 if (val < 0)
79 goto abort;
80
81 udelay(30);
82
83 for (i = 0; i < 3; i++) {
84 val = i2c_smbus_read_word_swapped(client,
85 AD7418_REG_TEMP[i]);
86 if (val < 0)
87 goto abort;
88
89 data->temp[i] = val;
90 }
91
92 for (i = 0, ch = 4; i < data->adc_max; i++, ch--) {
93 val = i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
94 cfg | AD7418_REG_ADC_CH(ch));
95 if (val < 0)
96 goto abort;
97
98 udelay(15);
99 val = i2c_smbus_read_word_swapped(client,
100 AD7418_REG_ADC);
101 if (val < 0)
102 goto abort;
103
104 data->in[data->adc_max - 1 - i] = val;
105 }
106
107 /* restore old configuration value */
108 val = i2c_smbus_write_word_swapped(client, AD7418_REG_CONF,
109 cfg);
110 if (val < 0)
111 goto abort;
112
113 data->last_updated = jiffies;
114 data->valid = true;
115 }
116
117 mutex_unlock(&data->lock);
118 return 0;
119
120 abort:
121 data->valid = false;
122 mutex_unlock(&data->lock);
123 return val;
124 }
125
temp_show(struct device * dev,struct device_attribute * devattr,char * buf)126 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
127 char *buf)
128 {
129 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
130 struct ad7418_data *data = dev_get_drvdata(dev);
131 int ret;
132
133 ret = ad7418_update_device(dev);
134 if (ret < 0)
135 return ret;
136
137 return sprintf(buf, "%d\n",
138 LM75_TEMP_FROM_REG(data->temp[attr->index]));
139 }
140
adc_show(struct device * dev,struct device_attribute * devattr,char * buf)141 static ssize_t adc_show(struct device *dev, struct device_attribute *devattr,
142 char *buf)
143 {
144 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
145 struct ad7418_data *data = dev_get_drvdata(dev);
146 int ret;
147
148 ret = ad7418_update_device(dev);
149 if (ret < 0)
150 return ret;
151
152 return sprintf(buf, "%d\n",
153 ((data->in[attr->index] >> 6) * 2500 + 512) / 1024);
154 }
155
temp_store(struct device * dev,struct device_attribute * devattr,const char * buf,size_t count)156 static ssize_t temp_store(struct device *dev,
157 struct device_attribute *devattr, const char *buf,
158 size_t count)
159 {
160 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
161 struct ad7418_data *data = dev_get_drvdata(dev);
162 struct i2c_client *client = data->client;
163 long temp;
164 int ret = kstrtol(buf, 10, &temp);
165
166 if (ret < 0)
167 return ret;
168
169 mutex_lock(&data->lock);
170 data->temp[attr->index] = LM75_TEMP_TO_REG(temp);
171 i2c_smbus_write_word_swapped(client,
172 AD7418_REG_TEMP[attr->index],
173 data->temp[attr->index]);
174 mutex_unlock(&data->lock);
175 return count;
176 }
177
178 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
179 static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, temp, 1);
180 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, 2);
181
182 static SENSOR_DEVICE_ATTR_RO(in1_input, adc, 0);
183 static SENSOR_DEVICE_ATTR_RO(in2_input, adc, 1);
184 static SENSOR_DEVICE_ATTR_RO(in3_input, adc, 2);
185 static SENSOR_DEVICE_ATTR_RO(in4_input, adc, 3);
186
187 static struct attribute *ad7416_attrs[] = {
188 &sensor_dev_attr_temp1_max.dev_attr.attr,
189 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
190 &sensor_dev_attr_temp1_input.dev_attr.attr,
191 NULL
192 };
193 ATTRIBUTE_GROUPS(ad7416);
194
195 static struct attribute *ad7417_attrs[] = {
196 &sensor_dev_attr_temp1_max.dev_attr.attr,
197 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
198 &sensor_dev_attr_temp1_input.dev_attr.attr,
199 &sensor_dev_attr_in1_input.dev_attr.attr,
200 &sensor_dev_attr_in2_input.dev_attr.attr,
201 &sensor_dev_attr_in3_input.dev_attr.attr,
202 &sensor_dev_attr_in4_input.dev_attr.attr,
203 NULL
204 };
205 ATTRIBUTE_GROUPS(ad7417);
206
207 static struct attribute *ad7418_attrs[] = {
208 &sensor_dev_attr_temp1_max.dev_attr.attr,
209 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
210 &sensor_dev_attr_temp1_input.dev_attr.attr,
211 &sensor_dev_attr_in1_input.dev_attr.attr,
212 NULL
213 };
214 ATTRIBUTE_GROUPS(ad7418);
215
ad7418_init_client(struct i2c_client * client)216 static void ad7418_init_client(struct i2c_client *client)
217 {
218 struct ad7418_data *data = i2c_get_clientdata(client);
219
220 int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
221 if (reg < 0) {
222 dev_err(&client->dev, "cannot read configuration register\n");
223 } else {
224 dev_info(&client->dev, "configuring for mode 1\n");
225 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe);
226
227 if (data->type == ad7417 || data->type == ad7418)
228 i2c_smbus_write_byte_data(client,
229 AD7418_REG_CONF2, 0x00);
230 }
231 }
232
233 static const struct i2c_device_id ad7418_id[];
234
ad7418_probe(struct i2c_client * client)235 static int ad7418_probe(struct i2c_client *client)
236 {
237 struct device *dev = &client->dev;
238 struct i2c_adapter *adapter = client->adapter;
239 struct ad7418_data *data;
240 struct device *hwmon_dev;
241 const struct attribute_group **attr_groups = NULL;
242
243 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
244 I2C_FUNC_SMBUS_WORD_DATA))
245 return -EOPNOTSUPP;
246
247 data = devm_kzalloc(dev, sizeof(struct ad7418_data), GFP_KERNEL);
248 if (!data)
249 return -ENOMEM;
250
251 i2c_set_clientdata(client, data);
252
253 mutex_init(&data->lock);
254 data->client = client;
255 if (dev->of_node)
256 data->type = (uintptr_t)of_device_get_match_data(dev);
257 else
258 data->type = i2c_match_id(ad7418_id, client)->driver_data;
259
260 switch (data->type) {
261 case ad7416:
262 data->adc_max = 0;
263 attr_groups = ad7416_groups;
264 break;
265
266 case ad7417:
267 data->adc_max = 4;
268 attr_groups = ad7417_groups;
269 break;
270
271 case ad7418:
272 data->adc_max = 1;
273 attr_groups = ad7418_groups;
274 break;
275 }
276
277 dev_info(dev, "%s chip found\n", client->name);
278
279 /* Initialize the AD7418 chip */
280 ad7418_init_client(client);
281
282 hwmon_dev = devm_hwmon_device_register_with_groups(dev,
283 client->name,
284 data, attr_groups);
285 return PTR_ERR_OR_ZERO(hwmon_dev);
286 }
287
288 static const struct i2c_device_id ad7418_id[] = {
289 { "ad7416", ad7416 },
290 { "ad7417", ad7417 },
291 { "ad7418", ad7418 },
292 { }
293 };
294 MODULE_DEVICE_TABLE(i2c, ad7418_id);
295
296 static const struct of_device_id ad7418_dt_ids[] = {
297 { .compatible = "adi,ad7416", .data = (void *)ad7416, },
298 { .compatible = "adi,ad7417", .data = (void *)ad7417, },
299 { .compatible = "adi,ad7418", .data = (void *)ad7418, },
300 { }
301 };
302 MODULE_DEVICE_TABLE(of, ad7418_dt_ids);
303
304 static struct i2c_driver ad7418_driver = {
305 .driver = {
306 .name = "ad7418",
307 .of_match_table = ad7418_dt_ids,
308 },
309 .probe = ad7418_probe,
310 .id_table = ad7418_id,
311 };
312
313 module_i2c_driver(ad7418_driver);
314
315 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
316 MODULE_DESCRIPTION("AD7416/17/18 driver");
317 MODULE_LICENSE("GPL");
318 MODULE_VERSION(DRV_VERSION);
319