1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * LM73 Sensor driver |
4 | * Based on LM75 |
5 | * |
6 | * Copyright (C) 2007, CenoSYS (www.cenosys.com). |
7 | * Copyright (C) 2009, Bollore telecom (www.bolloretelecom.eu). |
8 | * |
9 | * Guillaume Ligneul <guillaume.ligneul@gmail.com> |
10 | * Adrien Demarez <adrien.demarez@bolloretelecom.eu> |
11 | * Jeremy Laine <jeremy.laine@bolloretelecom.eu> |
12 | * Chris Verges <kg4ysn@gmail.com> |
13 | */ |
14 | |
15 | #include <linux/module.h> |
16 | #include <linux/init.h> |
17 | #include <linux/i2c.h> |
18 | #include <linux/hwmon.h> |
19 | #include <linux/hwmon-sysfs.h> |
20 | #include <linux/err.h> |
21 | |
22 | |
23 | /* Addresses scanned */ |
24 | static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4c, |
25 | 0x4d, 0x4e, I2C_CLIENT_END }; |
26 | |
27 | /* LM73 registers */ |
28 | #define LM73_REG_INPUT 0x00 |
29 | #define LM73_REG_CONF 0x01 |
30 | #define LM73_REG_MAX 0x02 |
31 | #define LM73_REG_MIN 0x03 |
32 | #define LM73_REG_CTRL 0x04 |
33 | #define LM73_REG_ID 0x07 |
34 | |
35 | #define LM73_ID 0x9001 /* 0x0190, byte-swapped */ |
36 | #define DRVNAME "lm73" |
37 | #define LM73_TEMP_MIN (-256000 / 250) |
38 | #define LM73_TEMP_MAX (255750 / 250) |
39 | |
40 | #define LM73_CTRL_RES_SHIFT 5 |
41 | #define LM73_CTRL_RES_MASK (BIT(5) | BIT(6)) |
42 | #define LM73_CTRL_TO_MASK BIT(7) |
43 | |
44 | #define LM73_CTRL_HI_SHIFT 2 |
45 | #define LM73_CTRL_LO_SHIFT 1 |
46 | |
47 | static const unsigned short lm73_convrates[] = { |
48 | 14, /* 11-bits (0.25000 C/LSB): RES1 Bit = 0, RES0 Bit = 0 */ |
49 | 28, /* 12-bits (0.12500 C/LSB): RES1 Bit = 0, RES0 Bit = 1 */ |
50 | 56, /* 13-bits (0.06250 C/LSB): RES1 Bit = 1, RES0 Bit = 0 */ |
51 | 112, /* 14-bits (0.03125 C/LSB): RES1 Bit = 1, RES0 Bit = 1 */ |
52 | }; |
53 | |
54 | struct lm73_data { |
55 | struct i2c_client *client; |
56 | struct mutex lock; |
57 | u8 ctrl; /* control register value */ |
58 | }; |
59 | |
60 | /*-----------------------------------------------------------------------*/ |
61 | |
62 | static ssize_t temp_store(struct device *dev, struct device_attribute *da, |
63 | const char *buf, size_t count) |
64 | { |
65 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
66 | struct lm73_data *data = dev_get_drvdata(dev); |
67 | long temp; |
68 | short value; |
69 | s32 err; |
70 | |
71 | int status = kstrtol(s: buf, base: 10, res: &temp); |
72 | if (status < 0) |
73 | return status; |
74 | |
75 | /* Write value */ |
76 | value = clamp_val(temp / 250, LM73_TEMP_MIN, LM73_TEMP_MAX) << 5; |
77 | err = i2c_smbus_write_word_swapped(client: data->client, command: attr->index, value); |
78 | return (err < 0) ? err : count; |
79 | } |
80 | |
81 | static ssize_t temp_show(struct device *dev, struct device_attribute *da, |
82 | char *buf) |
83 | { |
84 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
85 | struct lm73_data *data = dev_get_drvdata(dev); |
86 | int temp; |
87 | |
88 | s32 err = i2c_smbus_read_word_swapped(client: data->client, command: attr->index); |
89 | if (err < 0) |
90 | return err; |
91 | |
92 | /* use integer division instead of equivalent right shift to |
93 | guarantee arithmetic shift and preserve the sign */ |
94 | temp = (((s16) err) * 250) / 32; |
95 | return sysfs_emit(buf, fmt: "%d\n" , temp); |
96 | } |
97 | |
98 | static ssize_t convrate_store(struct device *dev, struct device_attribute *da, |
99 | const char *buf, size_t count) |
100 | { |
101 | struct lm73_data *data = dev_get_drvdata(dev); |
102 | unsigned long convrate; |
103 | s32 err; |
104 | int res = 0; |
105 | |
106 | err = kstrtoul(s: buf, base: 10, res: &convrate); |
107 | if (err < 0) |
108 | return err; |
109 | |
110 | /* |
111 | * Convert the desired conversion rate into register bits. |
112 | * res is already initialized, and everything past the second-to-last |
113 | * value in the array is treated as belonging to the last value |
114 | * in the array. |
115 | */ |
116 | while (res < (ARRAY_SIZE(lm73_convrates) - 1) && |
117 | convrate > lm73_convrates[res]) |
118 | res++; |
119 | |
120 | mutex_lock(&data->lock); |
121 | data->ctrl &= LM73_CTRL_TO_MASK; |
122 | data->ctrl |= res << LM73_CTRL_RES_SHIFT; |
123 | err = i2c_smbus_write_byte_data(client: data->client, LM73_REG_CTRL, |
124 | value: data->ctrl); |
125 | mutex_unlock(lock: &data->lock); |
126 | |
127 | if (err < 0) |
128 | return err; |
129 | |
130 | return count; |
131 | } |
132 | |
133 | static ssize_t convrate_show(struct device *dev, struct device_attribute *da, |
134 | char *buf) |
135 | { |
136 | struct lm73_data *data = dev_get_drvdata(dev); |
137 | int res; |
138 | |
139 | res = (data->ctrl & LM73_CTRL_RES_MASK) >> LM73_CTRL_RES_SHIFT; |
140 | return sysfs_emit(buf, fmt: "%hu\n" , lm73_convrates[res]); |
141 | } |
142 | |
143 | static ssize_t maxmin_alarm_show(struct device *dev, |
144 | struct device_attribute *da, char *buf) |
145 | { |
146 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); |
147 | struct lm73_data *data = dev_get_drvdata(dev); |
148 | s32 ctrl; |
149 | |
150 | mutex_lock(&data->lock); |
151 | ctrl = i2c_smbus_read_byte_data(client: data->client, LM73_REG_CTRL); |
152 | if (ctrl < 0) |
153 | goto abort; |
154 | data->ctrl = ctrl; |
155 | mutex_unlock(lock: &data->lock); |
156 | |
157 | return sysfs_emit(buf, fmt: "%d\n" , (ctrl >> attr->index) & 1); |
158 | |
159 | abort: |
160 | mutex_unlock(lock: &data->lock); |
161 | return ctrl; |
162 | } |
163 | |
164 | /*-----------------------------------------------------------------------*/ |
165 | |
166 | /* sysfs attributes for hwmon */ |
167 | |
168 | static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, LM73_REG_MAX); |
169 | static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, LM73_REG_MIN); |
170 | static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, LM73_REG_INPUT); |
171 | static SENSOR_DEVICE_ATTR_RW(update_interval, convrate, 0); |
172 | static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, maxmin_alarm, |
173 | LM73_CTRL_HI_SHIFT); |
174 | static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, maxmin_alarm, |
175 | LM73_CTRL_LO_SHIFT); |
176 | |
177 | static struct attribute *lm73_attrs[] = { |
178 | &sensor_dev_attr_temp1_input.dev_attr.attr, |
179 | &sensor_dev_attr_temp1_max.dev_attr.attr, |
180 | &sensor_dev_attr_temp1_min.dev_attr.attr, |
181 | &sensor_dev_attr_update_interval.dev_attr.attr, |
182 | &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, |
183 | &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, |
184 | NULL |
185 | }; |
186 | ATTRIBUTE_GROUPS(lm73); |
187 | |
188 | /*-----------------------------------------------------------------------*/ |
189 | |
190 | /* device probe and removal */ |
191 | |
192 | static int |
193 | lm73_probe(struct i2c_client *client) |
194 | { |
195 | struct device *dev = &client->dev; |
196 | struct device *hwmon_dev; |
197 | struct lm73_data *data; |
198 | int ctrl; |
199 | |
200 | data = devm_kzalloc(dev, size: sizeof(struct lm73_data), GFP_KERNEL); |
201 | if (!data) |
202 | return -ENOMEM; |
203 | |
204 | data->client = client; |
205 | mutex_init(&data->lock); |
206 | |
207 | ctrl = i2c_smbus_read_byte_data(client, LM73_REG_CTRL); |
208 | if (ctrl < 0) |
209 | return ctrl; |
210 | data->ctrl = ctrl; |
211 | |
212 | hwmon_dev = devm_hwmon_device_register_with_groups(dev, name: client->name, |
213 | drvdata: data, groups: lm73_groups); |
214 | if (IS_ERR(ptr: hwmon_dev)) |
215 | return PTR_ERR(ptr: hwmon_dev); |
216 | |
217 | dev_info(dev, "sensor '%s'\n" , client->name); |
218 | |
219 | return 0; |
220 | } |
221 | |
222 | static const struct i2c_device_id lm73_ids[] = { |
223 | { "lm73" , 0 }, |
224 | { /* LIST END */ } |
225 | }; |
226 | MODULE_DEVICE_TABLE(i2c, lm73_ids); |
227 | |
228 | /* Return 0 if detection is successful, -ENODEV otherwise */ |
229 | static int lm73_detect(struct i2c_client *new_client, |
230 | struct i2c_board_info *info) |
231 | { |
232 | struct i2c_adapter *adapter = new_client->adapter; |
233 | int id, ctrl, conf; |
234 | |
235 | if (!i2c_check_functionality(adap: adapter, I2C_FUNC_SMBUS_BYTE_DATA | |
236 | I2C_FUNC_SMBUS_WORD_DATA)) |
237 | return -ENODEV; |
238 | |
239 | /* |
240 | * Do as much detection as possible with byte reads first, as word |
241 | * reads can confuse other devices. |
242 | */ |
243 | ctrl = i2c_smbus_read_byte_data(client: new_client, LM73_REG_CTRL); |
244 | if (ctrl < 0 || (ctrl & 0x10)) |
245 | return -ENODEV; |
246 | |
247 | conf = i2c_smbus_read_byte_data(client: new_client, LM73_REG_CONF); |
248 | if (conf < 0 || (conf & 0x0c)) |
249 | return -ENODEV; |
250 | |
251 | id = i2c_smbus_read_byte_data(client: new_client, LM73_REG_ID); |
252 | if (id < 0 || id != (LM73_ID & 0xff)) |
253 | return -ENODEV; |
254 | |
255 | /* Check device ID */ |
256 | id = i2c_smbus_read_word_data(client: new_client, LM73_REG_ID); |
257 | if (id < 0 || id != LM73_ID) |
258 | return -ENODEV; |
259 | |
260 | strscpy(info->type, "lm73" , I2C_NAME_SIZE); |
261 | |
262 | return 0; |
263 | } |
264 | |
265 | static const struct of_device_id lm73_of_match[] = { |
266 | { |
267 | .compatible = "ti,lm73" , |
268 | }, |
269 | { }, |
270 | }; |
271 | |
272 | MODULE_DEVICE_TABLE(of, lm73_of_match); |
273 | |
274 | static struct i2c_driver lm73_driver = { |
275 | .class = I2C_CLASS_HWMON, |
276 | .driver = { |
277 | .name = "lm73" , |
278 | .of_match_table = lm73_of_match, |
279 | }, |
280 | .probe = lm73_probe, |
281 | .id_table = lm73_ids, |
282 | .detect = lm73_detect, |
283 | .address_list = normal_i2c, |
284 | }; |
285 | |
286 | module_i2c_driver(lm73_driver); |
287 | |
288 | MODULE_AUTHOR("Guillaume Ligneul <guillaume.ligneul@gmail.com>" ); |
289 | MODULE_DESCRIPTION("LM73 driver" ); |
290 | MODULE_LICENSE("GPL" ); |
291 | |