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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * lm92 - Hardware monitoring driver
4 * Copyright (C) 2005-2008 Jean Delvare <jdelvare@suse.de>
5 *
6 * Based on the lm90 driver, with some ideas taken from the lm_sensors
7 * lm92 driver as well.
8 *
9 * The LM92 is a sensor chip made by National Semiconductor. It reports
10 * its own temperature with a 0.0625 deg resolution and a 0.33 deg
11 * accuracy. Complete datasheet can be obtained from National's website
12 * at:
13 * http://www.national.com/pf/LM/LM92.html
14 *
15 * This driver also supports the MAX6635 sensor chip made by Maxim.
16 * This chip is compatible with the LM92, but has a lesser accuracy
17 * (1.0 deg). Complete datasheet can be obtained from Maxim's website
18 * at:
19 * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074
20 *
21 * Since the LM92 was the first chipset supported by this driver, most
22 * comments will refer to this chipset, but are actually general and
23 * concern all supported chipsets, unless mentioned otherwise.
24 *
25 * Support could easily be added for the National Semiconductor LM76
26 * and Maxim MAX6633 and MAX6634 chips, which are mostly compatible
27 * with the LM92.
28 */
29
30#include <linux/module.h>
31#include <linux/init.h>
32#include <linux/slab.h>
33#include <linux/i2c.h>
34#include <linux/hwmon.h>
35#include <linux/hwmon-sysfs.h>
36#include <linux/err.h>
37#include <linux/mutex.h>
38#include <linux/jiffies.h>
39
40/*
41 * The LM92 and MAX6635 have 2 two-state pins for address selection,
42 * resulting in 4 possible addresses.
43 */
44static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
45 I2C_CLIENT_END };
46enum chips { lm92, max6635 };
47
48/* The LM92 registers */
49#define LM92_REG_CONFIG 0x01 /* 8-bit, RW */
50#define LM92_REG_TEMP 0x00 /* 16-bit, RO */
51#define LM92_REG_TEMP_HYST 0x02 /* 16-bit, RW */
52#define LM92_REG_TEMP_CRIT 0x03 /* 16-bit, RW */
53#define LM92_REG_TEMP_LOW 0x04 /* 16-bit, RW */
54#define LM92_REG_TEMP_HIGH 0x05 /* 16-bit, RW */
55#define LM92_REG_MAN_ID 0x07 /* 16-bit, RO, LM92 only */
56
57/*
58 * The LM92 uses signed 13-bit values with LSB = 0.0625 degree Celsius,
59 * left-justified in 16-bit registers. No rounding is done, with such
60 * a resolution it's just not worth it. Note that the MAX6635 doesn't
61 * make use of the 4 lower bits for limits (i.e. effective resolution
62 * for limits is 1 degree Celsius).
63 */
64static inline int TEMP_FROM_REG(s16 reg)
65{
66 return reg / 8 * 625 / 10;
67}
68
69static inline s16 TEMP_TO_REG(long val)
70{
71 val = clamp_val(val, -60000, 160000);
72 return val * 10 / 625 * 8;
73}
74
75/* Alarm flags are stored in the 3 LSB of the temperature register */
76static inline u8 ALARMS_FROM_REG(s16 reg)
77{
78 return reg & 0x0007;
79}
80
81enum temp_index {
82 t_input,
83 t_crit,
84 t_min,
85 t_max,
86 t_hyst,
87 t_num_regs
88};
89
90static const u8 regs[t_num_regs] = {
91 [t_input] = LM92_REG_TEMP,
92 [t_crit] = LM92_REG_TEMP_CRIT,
93 [t_min] = LM92_REG_TEMP_LOW,
94 [t_max] = LM92_REG_TEMP_HIGH,
95 [t_hyst] = LM92_REG_TEMP_HYST,
96};
97
98/* Client data (each client gets its own) */
99struct lm92_data {
100 struct i2c_client *client;
101 struct mutex update_lock;
102 char valid; /* zero until following fields are valid */
103 unsigned long last_updated; /* in jiffies */
104
105 /* registers values */
106 s16 temp[t_num_regs]; /* index with enum temp_index */
107};
108
109/*
110 * Sysfs attributes and callback functions
111 */
112
113static struct lm92_data *lm92_update_device(struct device *dev)
114{
115 struct lm92_data *data = dev_get_drvdata(dev);
116 struct i2c_client *client = data->client;
117 int i;
118
119 mutex_lock(&data->update_lock);
120
121 if (time_after(jiffies, data->last_updated + HZ) ||
122 !data->valid) {
123 dev_dbg(&client->dev, "Updating lm92 data\n");
124 for (i = 0; i < t_num_regs; i++) {
125 data->temp[i] =
126 i2c_smbus_read_word_swapped(client, regs[i]);
127 }
128 data->last_updated = jiffies;
129 data->valid = 1;
130 }
131
132 mutex_unlock(&data->update_lock);
133
134 return data;
135}
136
137static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
138 char *buf)
139{
140 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
141 struct lm92_data *data = lm92_update_device(dev);
142
143 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
144}
145
146static ssize_t temp_store(struct device *dev,
147 struct device_attribute *devattr, const char *buf,
148 size_t count)
149{
150 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
151 struct lm92_data *data = dev_get_drvdata(dev);
152 struct i2c_client *client = data->client;
153 int nr = attr->index;
154 long val;
155 int err;
156
157 err = kstrtol(buf, 10, &val);
158 if (err)
159 return err;
160
161 mutex_lock(&data->update_lock);
162 data->temp[nr] = TEMP_TO_REG(val);
163 i2c_smbus_write_word_swapped(client, regs[nr], data->temp[nr]);
164 mutex_unlock(&data->update_lock);
165 return count;
166}
167
168static ssize_t temp_hyst_show(struct device *dev,
169 struct device_attribute *devattr, char *buf)
170{
171 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
172 struct lm92_data *data = lm92_update_device(dev);
173
174 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])
175 - TEMP_FROM_REG(data->temp[t_hyst]));
176}
177
178static ssize_t temp1_min_hyst_show(struct device *dev,
179 struct device_attribute *attr, char *buf)
180{
181 struct lm92_data *data = lm92_update_device(dev);
182
183 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[t_min])
184 + TEMP_FROM_REG(data->temp[t_hyst]));
185}
186
187static ssize_t temp_hyst_store(struct device *dev,
188 struct device_attribute *devattr,
189 const char *buf, size_t count)
190{
191 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
192 struct lm92_data *data = dev_get_drvdata(dev);
193 struct i2c_client *client = data->client;
194 long val;
195 int err;
196
197 err = kstrtol(buf, 10, &val);
198 if (err)
199 return err;
200
201 val = clamp_val(val, -120000, 220000);
202 mutex_lock(&data->update_lock);
203 data->temp[t_hyst] =
204 TEMP_TO_REG(TEMP_FROM_REG(data->temp[attr->index]) - val);
205 i2c_smbus_write_word_swapped(client, LM92_REG_TEMP_HYST,
206 data->temp[t_hyst]);
207 mutex_unlock(&data->update_lock);
208 return count;
209}
210
211static ssize_t alarms_show(struct device *dev, struct device_attribute *attr,
212 char *buf)
213{
214 struct lm92_data *data = lm92_update_device(dev);
215
216 return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->temp[t_input]));
217}
218
219static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
220 char *buf)
221{
222 int bitnr = to_sensor_dev_attr(attr)->index;
223 struct lm92_data *data = lm92_update_device(dev);
224 return sprintf(buf, "%d\n", (data->temp[t_input] >> bitnr) & 1);
225}
226
227static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, t_input);
228static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp, t_crit);
229static SENSOR_DEVICE_ATTR_RW(temp1_crit_hyst, temp_hyst, t_crit);
230static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, t_min);
231static DEVICE_ATTR_RO(temp1_min_hyst);
232static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, t_max);
233static SENSOR_DEVICE_ATTR_RO(temp1_max_hyst, temp_hyst, t_max);
234static DEVICE_ATTR_RO(alarms);
235static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 2);
236static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, alarm, 0);
237static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 1);
238
239/*
240 * Detection and registration
241 */
242
243static void lm92_init_client(struct i2c_client *client)
244{
245 u8 config;
246
247 /* Start the conversions if needed */
248 config = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG);
249 if (config & 0x01)
250 i2c_smbus_write_byte_data(client, LM92_REG_CONFIG,
251 config & 0xFE);
252}
253
254static struct attribute *lm92_attrs[] = {
255 &sensor_dev_attr_temp1_input.dev_attr.attr,
256 &sensor_dev_attr_temp1_crit.dev_attr.attr,
257 &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
258 &sensor_dev_attr_temp1_min.dev_attr.attr,
259 &dev_attr_temp1_min_hyst.attr,
260 &sensor_dev_attr_temp1_max.dev_attr.attr,
261 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
262 &dev_attr_alarms.attr,
263 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
264 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
265 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
266 NULL
267};
268ATTRIBUTE_GROUPS(lm92);
269
270/* Return 0 if detection is successful, -ENODEV otherwise */
271static int lm92_detect(struct i2c_client *new_client,
272 struct i2c_board_info *info)
273{
274 struct i2c_adapter *adapter = new_client->adapter;
275 u8 config;
276 u16 man_id;
277
278 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
279 | I2C_FUNC_SMBUS_WORD_DATA))
280 return -ENODEV;
281
282 config = i2c_smbus_read_byte_data(new_client, LM92_REG_CONFIG);
283 man_id = i2c_smbus_read_word_data(new_client, LM92_REG_MAN_ID);
284
285 if ((config & 0xe0) == 0x00 && man_id == 0x0180)
286 pr_info("lm92: Found National Semiconductor LM92 chip\n");
287 else
288 return -ENODEV;
289
290 strlcpy(info->type, "lm92", I2C_NAME_SIZE);
291
292 return 0;
293}
294
295static int lm92_probe(struct i2c_client *new_client,
296 const struct i2c_device_id *id)
297{
298 struct device *hwmon_dev;
299 struct lm92_data *data;
300
301 data = devm_kzalloc(&new_client->dev, sizeof(struct lm92_data),
302 GFP_KERNEL);
303 if (!data)
304 return -ENOMEM;
305
306 data->client = new_client;
307 mutex_init(&data->update_lock);
308
309 /* Initialize the chipset */
310 lm92_init_client(new_client);
311
312 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev,
313 new_client->name,
314 data, lm92_groups);
315 return PTR_ERR_OR_ZERO(hwmon_dev);
316}
317
318/*
319 * Module and driver stuff
320 */
321
322static const struct i2c_device_id lm92_id[] = {
323 { "lm92", lm92 },
324 { "max6635", max6635 },
325 { }
326};
327MODULE_DEVICE_TABLE(i2c, lm92_id);
328
329static struct i2c_driver lm92_driver = {
330 .class = I2C_CLASS_HWMON,
331 .driver = {
332 .name = "lm92",
333 },
334 .probe = lm92_probe,
335 .id_table = lm92_id,
336 .detect = lm92_detect,
337 .address_list = normal_i2c,
338};
339
340module_i2c_driver(lm92_driver);
341
342MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
343MODULE_DESCRIPTION("LM92/MAX6635 driver");
344MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * lm92 - Hardware monitoring driver
4 * Copyright (C) 2005-2008 Jean Delvare <jdelvare@suse.de>
5 *
6 * Based on the lm90 driver, with some ideas taken from the lm_sensors
7 * lm92 driver as well.
8 *
9 * The LM92 is a sensor chip made by National Semiconductor. It reports
10 * its own temperature with a 0.0625 deg resolution and a 0.33 deg
11 * accuracy. Complete datasheet can be obtained from National's website
12 * at:
13 * http://www.national.com/pf/LM/LM92.html
14 *
15 * This driver also supports the MAX6635 sensor chip made by Maxim.
16 * This chip is compatible with the LM92, but has a lesser accuracy
17 * (1.0 deg). Complete datasheet can be obtained from Maxim's website
18 * at:
19 * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074
20 *
21 * Since the LM92 was the first chipset supported by this driver, most
22 * comments will refer to this chipset, but are actually general and
23 * concern all supported chipsets, unless mentioned otherwise.
24 *
25 * Support could easily be added for the National Semiconductor LM76
26 * and Maxim MAX6633 and MAX6634 chips, which are mostly compatible
27 * with the LM92.
28 */
29
30#include <linux/err.h>
31#include <linux/hwmon.h>
32#include <linux/i2c.h>
33#include <linux/init.h>
34#include <linux/module.h>
35#include <linux/mutex.h>
36#include <linux/regmap.h>
37#include <linux/slab.h>
38
39/*
40 * The LM92 and MAX6635 have 2 two-state pins for address selection,
41 * resulting in 4 possible addresses.
42 */
43static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
44 I2C_CLIENT_END };
45/* The LM92 registers */
46#define LM92_REG_CONFIG 0x01 /* 8-bit, RW */
47#define LM92_REG_TEMP 0x00 /* 16-bit, RO */
48#define LM92_REG_TEMP_HYST 0x02 /* 16-bit, RW */
49#define LM92_REG_TEMP_CRIT 0x03 /* 16-bit, RW */
50#define LM92_REG_TEMP_LOW 0x04 /* 16-bit, RW */
51#define LM92_REG_TEMP_HIGH 0x05 /* 16-bit, RW */
52#define LM92_REG_MAN_ID 0x07 /* 16-bit, RO, LM92 only */
53
54/*
55 * The LM92 uses signed 13-bit values with LSB = 0.0625 degree Celsius,
56 * left-justified in 16-bit registers. No rounding is done, with such
57 * a resolution it's just not worth it. Note that the MAX6635 doesn't
58 * make use of the 4 lower bits for limits (i.e. effective resolution
59 * for limits is 1 degree Celsius).
60 */
61static inline int TEMP_FROM_REG(s16 reg)
62{
63 return reg / 8 * 625 / 10;
64}
65
66static inline s16 TEMP_TO_REG(long val, int resolution)
67{
68 val = clamp_val(val, -60000, 160000);
69 return DIV_ROUND_CLOSEST(val << (resolution - 9), 1000) << (16 - resolution);
70}
71
72/* Alarm flags are stored in the 3 LSB of the temperature register */
73static inline u8 ALARMS_FROM_REG(s16 reg)
74{
75 return reg & 0x0007;
76}
77
78/* Client data (each client gets its own) */
79struct lm92_data {
80 struct regmap *regmap;
81 struct mutex update_lock;
82 int resolution;
83};
84
85static int lm92_temp_read(struct lm92_data *data, u32 attr, int channel, long *val)
86{
87 int reg = -1, hyst_reg = -1, alarm_bit = 0;
88 struct regmap *regmap = data->regmap;
89 u32 temp;
90 int ret;
91
92 switch (attr) {
93 case hwmon_temp_input:
94 reg = LM92_REG_TEMP;
95 break;
96 case hwmon_temp_min:
97 reg = LM92_REG_TEMP_LOW;
98 break;
99 case hwmon_temp_max:
100 reg = LM92_REG_TEMP_HIGH;
101 break;
102 case hwmon_temp_crit:
103 reg = LM92_REG_TEMP_CRIT;
104 break;
105 case hwmon_temp_min_hyst:
106 hyst_reg = LM92_REG_TEMP_LOW;
107 break;
108 case hwmon_temp_max_hyst:
109 hyst_reg = LM92_REG_TEMP_HIGH;
110 break;
111 case hwmon_temp_crit_hyst:
112 hyst_reg = LM92_REG_TEMP_CRIT;
113 break;
114 case hwmon_temp_min_alarm:
115 alarm_bit = 0;
116 break;
117 case hwmon_temp_max_alarm:
118 alarm_bit = 1;
119 break;
120 case hwmon_temp_crit_alarm:
121 alarm_bit = 2;
122 break;
123 default:
124 return -EOPNOTSUPP;
125 }
126 if (reg >= 0) {
127 ret = regmap_read(regmap, reg, &temp);
128 if (ret < 0)
129 return ret;
130 *val = TEMP_FROM_REG(temp);
131 } else if (hyst_reg >= 0) {
132 u32 regs[2] = { hyst_reg, LM92_REG_TEMP_HYST };
133 u16 regvals[2];
134
135 ret = regmap_multi_reg_read(regmap, regs, regvals, 2);
136 if (ret)
137 return ret;
138 if (attr == hwmon_temp_min_hyst)
139 *val = TEMP_FROM_REG(regvals[0]) + TEMP_FROM_REG(regvals[1]);
140 else
141 *val = TEMP_FROM_REG(regvals[0]) - TEMP_FROM_REG(regvals[1]);
142 } else {
143 ret = regmap_read(regmap, LM92_REG_TEMP, &temp);
144 if (ret)
145 return ret;
146 *val = !!(temp & BIT(alarm_bit));
147 }
148 return 0;
149}
150
151static int lm92_chip_read(struct lm92_data *data, u32 attr, long *val)
152{
153 u32 temp;
154 int ret;
155
156 switch (attr) {
157 case hwmon_chip_alarms:
158 ret = regmap_read(data->regmap, LM92_REG_TEMP, &temp);
159 if (ret)
160 return ret;
161 *val = ALARMS_FROM_REG(temp);
162 break;
163 default:
164 return -EOPNOTSUPP;
165 }
166 return 0;
167}
168
169static int lm92_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
170 int channel, long *val)
171{
172 struct lm92_data *data = dev_get_drvdata(dev);
173
174 switch (type) {
175 case hwmon_chip:
176 return lm92_chip_read(data, attr, val);
177 case hwmon_temp:
178 return lm92_temp_read(data, attr, channel, val);
179 default:
180 return -EOPNOTSUPP;
181 }
182}
183
184static int lm92_temp_write(struct lm92_data *data, u32 attr, long val)
185{
186 struct regmap *regmap = data->regmap;
187 int reg, err;
188 u32 temp;
189
190 switch (attr) {
191 case hwmon_temp_min:
192 reg = LM92_REG_TEMP_LOW;
193 break;
194 case hwmon_temp_max:
195 reg = LM92_REG_TEMP_HIGH;
196 break;
197 case hwmon_temp_crit:
198 reg = LM92_REG_TEMP_CRIT;
199 break;
200 case hwmon_temp_crit_hyst:
201 val = clamp_val(val, -120000, 220000);
202 mutex_lock(&data->update_lock);
203 err = regmap_read(regmap, LM92_REG_TEMP_CRIT, &temp);
204 if (err)
205 goto unlock;
206 val = TEMP_TO_REG(TEMP_FROM_REG(temp) - val, data->resolution);
207 err = regmap_write(regmap, LM92_REG_TEMP_HYST, val);
208unlock:
209 mutex_unlock(&data->update_lock);
210 return err;
211 default:
212 return -EOPNOTSUPP;
213 }
214 return regmap_write(regmap, reg, TEMP_TO_REG(val, data->resolution));
215}
216
217static int lm92_write(struct device *dev, enum hwmon_sensor_types type,
218 u32 attr, int channel, long val)
219{
220 struct lm92_data *data = dev_get_drvdata(dev);
221
222 switch (type) {
223 case hwmon_temp:
224 return lm92_temp_write(data, attr, val);
225 default:
226 return -EOPNOTSUPP;
227 }
228}
229
230static umode_t lm92_is_visible(const void *_data, enum hwmon_sensor_types type,
231 u32 attr, int channel)
232{
233 switch (type) {
234 case hwmon_chip:
235 switch (attr) {
236 case hwmon_chip_alarms:
237 return 0444;
238 default:
239 break;
240 }
241 break;
242 case hwmon_temp:
243 switch (attr) {
244 case hwmon_temp_min:
245 case hwmon_temp_max:
246 case hwmon_temp_crit:
247 case hwmon_temp_crit_hyst:
248 return 0644;
249 case hwmon_temp_input:
250 case hwmon_temp_min_hyst:
251 case hwmon_temp_max_hyst:
252 case hwmon_temp_min_alarm:
253 case hwmon_temp_max_alarm:
254 case hwmon_temp_crit_alarm:
255 return 0444;
256 default:
257 break;
258 }
259 break;
260 default:
261 break;
262 }
263 return 0;
264}
265
266static const struct hwmon_channel_info * const lm92_info[] = {
267 HWMON_CHANNEL_INFO(chip, HWMON_C_ALARMS),
268 HWMON_CHANNEL_INFO(temp,
269 HWMON_T_INPUT |
270 HWMON_T_MIN | HWMON_T_MIN_HYST |
271 HWMON_T_MAX | HWMON_T_MAX_HYST |
272 HWMON_T_CRIT | HWMON_T_CRIT_HYST |
273 HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM |
274 HWMON_T_CRIT_ALARM),
275 NULL
276};
277
278static const struct hwmon_ops lm92_hwmon_ops = {
279 .is_visible = lm92_is_visible,
280 .read = lm92_read,
281 .write = lm92_write,
282};
283
284static const struct hwmon_chip_info lm92_chip_info = {
285 .ops = &lm92_hwmon_ops,
286 .info = lm92_info,
287};
288
289/*
290 * Detection and registration
291 */
292
293static int lm92_init_client(struct regmap *regmap)
294{
295 return regmap_clear_bits(regmap, LM92_REG_CONFIG, 0x01);
296}
297
298/* Return 0 if detection is successful, -ENODEV otherwise */
299static int lm92_detect(struct i2c_client *new_client,
300 struct i2c_board_info *info)
301{
302 struct i2c_adapter *adapter = new_client->adapter;
303 u8 config_addr = LM92_REG_CONFIG;
304 u8 man_id_addr = LM92_REG_MAN_ID;
305 int i, regval;
306
307 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
308 | I2C_FUNC_SMBUS_WORD_DATA))
309 return -ENODEV;
310
311 /*
312 * Register values repeat with multiples of 8.
313 * Read twice to improve detection accuracy.
314 */
315 for (i = 0; i < 2; i++) {
316 regval = i2c_smbus_read_word_data(new_client, man_id_addr);
317 if (regval != 0x0180)
318 return -ENODEV;
319 regval = i2c_smbus_read_byte_data(new_client, config_addr);
320 if (regval < 0 || (regval & 0xe0))
321 return -ENODEV;
322 config_addr += 8;
323 man_id_addr += 8;
324 }
325
326 strscpy(info->type, "lm92", I2C_NAME_SIZE);
327
328 return 0;
329}
330
331/* regmap */
332
333static int lm92_reg_read(void *context, unsigned int reg, unsigned int *val)
334{
335 int ret;
336
337 if (reg == LM92_REG_CONFIG)
338 ret = i2c_smbus_read_byte_data(context, reg);
339 else
340 ret = i2c_smbus_read_word_swapped(context, reg);
341 if (ret < 0)
342 return ret;
343
344 *val = ret;
345 return 0;
346}
347
348static int lm92_reg_write(void *context, unsigned int reg, unsigned int val)
349{
350 if (reg == LM92_REG_CONFIG)
351 return i2c_smbus_write_byte_data(context, LM92_REG_CONFIG, val);
352
353 return i2c_smbus_write_word_swapped(context, reg, val);
354}
355
356static bool lm92_regmap_is_volatile(struct device *dev, unsigned int reg)
357{
358 return reg == LM92_REG_TEMP;
359}
360
361static bool lm92_regmap_is_writeable(struct device *dev, unsigned int reg)
362{
363 return reg >= LM92_REG_CONFIG;
364}
365
366static const struct regmap_config lm92_regmap_config = {
367 .reg_bits = 8,
368 .val_bits = 16,
369 .max_register = LM92_REG_TEMP_HIGH,
370 .cache_type = REGCACHE_MAPLE,
371 .volatile_reg = lm92_regmap_is_volatile,
372 .writeable_reg = lm92_regmap_is_writeable,
373};
374
375static const struct regmap_bus lm92_regmap_bus = {
376 .reg_write = lm92_reg_write,
377 .reg_read = lm92_reg_read,
378};
379
380static int lm92_probe(struct i2c_client *client)
381{
382 struct device *dev = &client->dev;
383 struct device *hwmon_dev;
384 struct lm92_data *data;
385 struct regmap *regmap;
386 int err;
387
388 regmap = devm_regmap_init(dev, &lm92_regmap_bus, client,
389 &lm92_regmap_config);
390 if (IS_ERR(regmap))
391 return PTR_ERR(regmap);
392
393 data = devm_kzalloc(dev, sizeof(struct lm92_data), GFP_KERNEL);
394 if (!data)
395 return -ENOMEM;
396
397 data->regmap = regmap;
398 data->resolution = (unsigned long)i2c_get_match_data(client);
399 mutex_init(&data->update_lock);
400
401 /* Initialize the chipset */
402 err = lm92_init_client(regmap);
403 if (err)
404 return err;
405
406 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, data,
407 &lm92_chip_info, NULL);
408 return PTR_ERR_OR_ZERO(hwmon_dev);
409}
410
411/*
412 * Module and driver stuff
413 */
414
415/* .driver_data is limit register resolution */
416static const struct i2c_device_id lm92_id[] = {
417 { "lm92", 13 },
418 { "max6635", 9 },
419 { }
420};
421MODULE_DEVICE_TABLE(i2c, lm92_id);
422
423static struct i2c_driver lm92_driver = {
424 .class = I2C_CLASS_HWMON,
425 .driver = {
426 .name = "lm92",
427 },
428 .probe = lm92_probe,
429 .id_table = lm92_id,
430 .detect = lm92_detect,
431 .address_list = normal_i2c,
432};
433
434module_i2c_driver(lm92_driver);
435
436MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
437MODULE_DESCRIPTION("LM92/MAX6635 driver");
438MODULE_LICENSE("GPL");