Merge tag 'staging-4.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
[linux-2.6-microblaze.git] / drivers / hwmon / tmp102.c
1 /* Texas Instruments TMP102 SMBus temperature sensor driver
2  *
3  * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15
16 #include <linux/delay.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/i2c.h>
21 #include <linux/hwmon.h>
22 #include <linux/hwmon-sysfs.h>
23 #include <linux/err.h>
24 #include <linux/mutex.h>
25 #include <linux/device.h>
26 #include <linux/jiffies.h>
27 #include <linux/regmap.h>
28 #include <linux/of.h>
29
30 #define DRIVER_NAME "tmp102"
31
32 #define TMP102_TEMP_REG                 0x00
33 #define TMP102_CONF_REG                 0x01
34 /* note: these bit definitions are byte swapped */
35 #define         TMP102_CONF_SD          0x0100
36 #define         TMP102_CONF_TM          0x0200
37 #define         TMP102_CONF_POL         0x0400
38 #define         TMP102_CONF_F0          0x0800
39 #define         TMP102_CONF_F1          0x1000
40 #define         TMP102_CONF_R0          0x2000
41 #define         TMP102_CONF_R1          0x4000
42 #define         TMP102_CONF_OS          0x8000
43 #define         TMP102_CONF_EM          0x0010
44 #define         TMP102_CONF_AL          0x0020
45 #define         TMP102_CONF_CR0         0x0040
46 #define         TMP102_CONF_CR1         0x0080
47 #define TMP102_TLOW_REG                 0x02
48 #define TMP102_THIGH_REG                0x03
49
50 #define TMP102_CONFREG_MASK     (TMP102_CONF_SD | TMP102_CONF_TM | \
51                                  TMP102_CONF_POL | TMP102_CONF_F0 | \
52                                  TMP102_CONF_F1 | TMP102_CONF_OS | \
53                                  TMP102_CONF_EM | TMP102_CONF_AL | \
54                                  TMP102_CONF_CR0 | TMP102_CONF_CR1)
55
56 #define TMP102_CONFIG_CLEAR     (TMP102_CONF_SD | TMP102_CONF_OS | \
57                                  TMP102_CONF_CR0)
58 #define TMP102_CONFIG_SET       (TMP102_CONF_TM | TMP102_CONF_EM | \
59                                  TMP102_CONF_CR1)
60
61 #define CONVERSION_TIME_MS              35      /* in milli-seconds */
62
63 struct tmp102 {
64         struct regmap *regmap;
65         u16 config_orig;
66         unsigned long ready_time;
67 };
68
69 /* convert left adjusted 13-bit TMP102 register value to milliCelsius */
70 static inline int tmp102_reg_to_mC(s16 val)
71 {
72         return ((val & ~0x01) * 1000) / 128;
73 }
74
75 /* convert milliCelsius to left adjusted 13-bit TMP102 register value */
76 static inline u16 tmp102_mC_to_reg(int val)
77 {
78         return (val * 128) / 1000;
79 }
80
81 static int tmp102_read(struct device *dev, enum hwmon_sensor_types type,
82                        u32 attr, int channel, long *temp)
83 {
84         struct tmp102 *tmp102 = dev_get_drvdata(dev);
85         unsigned int regval;
86         int err, reg;
87
88         switch (attr) {
89         case hwmon_temp_input:
90                 /* Is it too early to return a conversion ? */
91                 if (time_before(jiffies, tmp102->ready_time)) {
92                         dev_dbg(dev, "%s: Conversion not ready yet..\n", __func__);
93                         return -EAGAIN;
94                 }
95                 reg = TMP102_TEMP_REG;
96                 break;
97         case hwmon_temp_max_hyst:
98                 reg = TMP102_TLOW_REG;
99                 break;
100         case hwmon_temp_max:
101                 reg = TMP102_THIGH_REG;
102                 break;
103         default:
104                 return -EOPNOTSUPP;
105         }
106
107         err = regmap_read(tmp102->regmap, reg, &regval);
108         if (err < 0)
109                 return err;
110         *temp = tmp102_reg_to_mC(regval);
111
112         return 0;
113 }
114
115 static int tmp102_write(struct device *dev, enum hwmon_sensor_types type,
116                         u32 attr, int channel, long temp)
117 {
118         struct tmp102 *tmp102 = dev_get_drvdata(dev);
119         int reg;
120
121         switch (attr) {
122         case hwmon_temp_max_hyst:
123                 reg = TMP102_TLOW_REG;
124                 break;
125         case hwmon_temp_max:
126                 reg = TMP102_THIGH_REG;
127                 break;
128         default:
129                 return -EOPNOTSUPP;
130         }
131
132         temp = clamp_val(temp, -256000, 255000);
133         return regmap_write(tmp102->regmap, reg, tmp102_mC_to_reg(temp));
134 }
135
136 static umode_t tmp102_is_visible(const void *data, enum hwmon_sensor_types type,
137                                  u32 attr, int channel)
138 {
139         if (type != hwmon_temp)
140                 return 0;
141
142         switch (attr) {
143         case hwmon_temp_input:
144                 return S_IRUGO;
145         case hwmon_temp_max_hyst:
146         case hwmon_temp_max:
147                 return S_IRUGO | S_IWUSR;
148         default:
149                 return 0;
150         }
151 }
152
153 static u32 tmp102_chip_config[] = {
154         HWMON_C_REGISTER_TZ,
155         0
156 };
157
158 static const struct hwmon_channel_info tmp102_chip = {
159         .type = hwmon_chip,
160         .config = tmp102_chip_config,
161 };
162
163 static u32 tmp102_temp_config[] = {
164         HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST,
165         0
166 };
167
168 static const struct hwmon_channel_info tmp102_temp = {
169         .type = hwmon_temp,
170         .config = tmp102_temp_config,
171 };
172
173 static const struct hwmon_channel_info *tmp102_info[] = {
174         &tmp102_chip,
175         &tmp102_temp,
176         NULL
177 };
178
179 static const struct hwmon_ops tmp102_hwmon_ops = {
180         .is_visible = tmp102_is_visible,
181         .read = tmp102_read,
182         .write = tmp102_write,
183 };
184
185 static const struct hwmon_chip_info tmp102_chip_info = {
186         .ops = &tmp102_hwmon_ops,
187         .info = tmp102_info,
188 };
189
190 static void tmp102_restore_config(void *data)
191 {
192         struct tmp102 *tmp102 = data;
193
194         regmap_write(tmp102->regmap, TMP102_CONF_REG, tmp102->config_orig);
195 }
196
197 static bool tmp102_is_writeable_reg(struct device *dev, unsigned int reg)
198 {
199         return reg != TMP102_TEMP_REG;
200 }
201
202 static bool tmp102_is_volatile_reg(struct device *dev, unsigned int reg)
203 {
204         return reg == TMP102_TEMP_REG;
205 }
206
207 static const struct regmap_config tmp102_regmap_config = {
208         .reg_bits = 8,
209         .val_bits = 16,
210         .max_register = TMP102_THIGH_REG,
211         .writeable_reg = tmp102_is_writeable_reg,
212         .volatile_reg = tmp102_is_volatile_reg,
213         .val_format_endian = REGMAP_ENDIAN_BIG,
214         .cache_type = REGCACHE_RBTREE,
215         .use_single_rw = true,
216 };
217
218 static int tmp102_probe(struct i2c_client *client,
219                         const struct i2c_device_id *id)
220 {
221         struct device *dev = &client->dev;
222         struct device *hwmon_dev;
223         struct tmp102 *tmp102;
224         unsigned int regval;
225         int err;
226
227         if (!i2c_check_functionality(client->adapter,
228                                      I2C_FUNC_SMBUS_WORD_DATA)) {
229                 dev_err(dev,
230                         "adapter doesn't support SMBus word transactions\n");
231                 return -ENODEV;
232         }
233
234         tmp102 = devm_kzalloc(dev, sizeof(*tmp102), GFP_KERNEL);
235         if (!tmp102)
236                 return -ENOMEM;
237
238         i2c_set_clientdata(client, tmp102);
239
240         tmp102->regmap = devm_regmap_init_i2c(client, &tmp102_regmap_config);
241         if (IS_ERR(tmp102->regmap))
242                 return PTR_ERR(tmp102->regmap);
243
244         err = regmap_read(tmp102->regmap, TMP102_CONF_REG, &regval);
245         if (err < 0) {
246                 dev_err(dev, "error reading config register\n");
247                 return err;
248         }
249
250         if ((regval & ~TMP102_CONFREG_MASK) !=
251             (TMP102_CONF_R0 | TMP102_CONF_R1)) {
252                 dev_err(dev, "unexpected config register value\n");
253                 return -ENODEV;
254         }
255
256         tmp102->config_orig = regval;
257
258         err = devm_add_action_or_reset(dev, tmp102_restore_config, tmp102);
259         if (err)
260                 return err;
261
262         regval &= ~TMP102_CONFIG_CLEAR;
263         regval |= TMP102_CONFIG_SET;
264
265         err = regmap_write(tmp102->regmap, TMP102_CONF_REG, regval);
266         if (err < 0) {
267                 dev_err(dev, "error writing config register\n");
268                 return err;
269         }
270
271         /*
272          * Mark that we are not ready with data until the first
273          * conversion is complete
274          */
275         tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
276
277         hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
278                                                          tmp102,
279                                                          &tmp102_chip_info,
280                                                          NULL);
281         if (IS_ERR(hwmon_dev)) {
282                 dev_dbg(dev, "unable to register hwmon device\n");
283                 return PTR_ERR(hwmon_dev);
284         }
285         dev_info(dev, "initialized\n");
286
287         return 0;
288 }
289
290 #ifdef CONFIG_PM_SLEEP
291 static int tmp102_suspend(struct device *dev)
292 {
293         struct i2c_client *client = to_i2c_client(dev);
294         struct tmp102 *tmp102 = i2c_get_clientdata(client);
295
296         return regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
297                                   TMP102_CONF_SD, TMP102_CONF_SD);
298 }
299
300 static int tmp102_resume(struct device *dev)
301 {
302         struct i2c_client *client = to_i2c_client(dev);
303         struct tmp102 *tmp102 = i2c_get_clientdata(client);
304         int err;
305
306         err = regmap_update_bits(tmp102->regmap, TMP102_CONF_REG,
307                                  TMP102_CONF_SD, 0);
308
309         tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS);
310
311         return err;
312 }
313 #endif /* CONFIG_PM */
314
315 static SIMPLE_DEV_PM_OPS(tmp102_dev_pm_ops, tmp102_suspend, tmp102_resume);
316
317 static const struct i2c_device_id tmp102_id[] = {
318         { "tmp102", 0 },
319         { }
320 };
321 MODULE_DEVICE_TABLE(i2c, tmp102_id);
322
323 static const struct of_device_id tmp102_of_match[] = {
324         { .compatible = "ti,tmp102" },
325         { },
326 };
327 MODULE_DEVICE_TABLE(of, tmp102_of_match);
328
329 static struct i2c_driver tmp102_driver = {
330         .driver.name    = DRIVER_NAME,
331         .driver.of_match_table = of_match_ptr(tmp102_of_match),
332         .driver.pm      = &tmp102_dev_pm_ops,
333         .probe          = tmp102_probe,
334         .id_table       = tmp102_id,
335 };
336
337 module_i2c_driver(tmp102_driver);
338
339 MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
340 MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
341 MODULE_LICENSE("GPL");