Merge tag 'mvebu-fixes-3.19' of git://git.infradead.org/linux-mvebu into fixes
[firefly-linux-kernel-4.4.55.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  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
18  */
19
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/slab.h>
23 #include <linux/i2c.h>
24 #include <linux/hwmon.h>
25 #include <linux/hwmon-sysfs.h>
26 #include <linux/err.h>
27 #include <linux/mutex.h>
28 #include <linux/device.h>
29 #include <linux/jiffies.h>
30 #include <linux/thermal.h>
31 #include <linux/of.h>
32
33 #define DRIVER_NAME "tmp102"
34
35 #define TMP102_TEMP_REG                 0x00
36 #define TMP102_CONF_REG                 0x01
37 /* note: these bit definitions are byte swapped */
38 #define         TMP102_CONF_SD          0x0100
39 #define         TMP102_CONF_TM          0x0200
40 #define         TMP102_CONF_POL         0x0400
41 #define         TMP102_CONF_F0          0x0800
42 #define         TMP102_CONF_F1          0x1000
43 #define         TMP102_CONF_R0          0x2000
44 #define         TMP102_CONF_R1          0x4000
45 #define         TMP102_CONF_OS          0x8000
46 #define         TMP102_CONF_EM          0x0010
47 #define         TMP102_CONF_AL          0x0020
48 #define         TMP102_CONF_CR0         0x0040
49 #define         TMP102_CONF_CR1         0x0080
50 #define TMP102_TLOW_REG                 0x02
51 #define TMP102_THIGH_REG                0x03
52
53 struct tmp102 {
54         struct i2c_client *client;
55         struct device *hwmon_dev;
56         struct thermal_zone_device *tz;
57         struct mutex lock;
58         u16 config_orig;
59         unsigned long last_update;
60         int temp[3];
61 };
62
63 /* convert left adjusted 13-bit TMP102 register value to milliCelsius */
64 static inline int tmp102_reg_to_mC(s16 val)
65 {
66         return ((val & ~0x01) * 1000) / 128;
67 }
68
69 /* convert milliCelsius to left adjusted 13-bit TMP102 register value */
70 static inline u16 tmp102_mC_to_reg(int val)
71 {
72         return (val * 128) / 1000;
73 }
74
75 static const u8 tmp102_reg[] = {
76         TMP102_TEMP_REG,
77         TMP102_TLOW_REG,
78         TMP102_THIGH_REG,
79 };
80
81 static struct tmp102 *tmp102_update_device(struct device *dev)
82 {
83         struct tmp102 *tmp102 = dev_get_drvdata(dev);
84         struct i2c_client *client = tmp102->client;
85
86         mutex_lock(&tmp102->lock);
87         if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
88                 int i;
89                 for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
90                         int status = i2c_smbus_read_word_swapped(client,
91                                                                  tmp102_reg[i]);
92                         if (status > -1)
93                                 tmp102->temp[i] = tmp102_reg_to_mC(status);
94                 }
95                 tmp102->last_update = jiffies;
96         }
97         mutex_unlock(&tmp102->lock);
98         return tmp102;
99 }
100
101 static int tmp102_read_temp(void *dev, long *temp)
102 {
103         struct tmp102 *tmp102 = tmp102_update_device(dev);
104
105         *temp = tmp102->temp[0];
106
107         return 0;
108 }
109
110 static ssize_t tmp102_show_temp(struct device *dev,
111                                 struct device_attribute *attr,
112                                 char *buf)
113 {
114         struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
115         struct tmp102 *tmp102 = tmp102_update_device(dev);
116
117         return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
118 }
119
120 static ssize_t tmp102_set_temp(struct device *dev,
121                                struct device_attribute *attr,
122                                const char *buf, size_t count)
123 {
124         struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
125         struct tmp102 *tmp102 = dev_get_drvdata(dev);
126         struct i2c_client *client = tmp102->client;
127         long val;
128         int status;
129
130         if (kstrtol(buf, 10, &val) < 0)
131                 return -EINVAL;
132         val = clamp_val(val, -256000, 255000);
133
134         mutex_lock(&tmp102->lock);
135         tmp102->temp[sda->index] = val;
136         status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index],
137                                               tmp102_mC_to_reg(val));
138         mutex_unlock(&tmp102->lock);
139         return status ? : count;
140 }
141
142 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
143
144 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
145                           tmp102_set_temp, 1);
146
147 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
148                           tmp102_set_temp, 2);
149
150 static struct attribute *tmp102_attrs[] = {
151         &sensor_dev_attr_temp1_input.dev_attr.attr,
152         &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
153         &sensor_dev_attr_temp1_max.dev_attr.attr,
154         NULL
155 };
156 ATTRIBUTE_GROUPS(tmp102);
157
158 #define TMP102_CONFIG  (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
159 #define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)
160
161 static const struct thermal_zone_of_device_ops tmp102_of_thermal_ops = {
162         .get_temp = tmp102_read_temp,
163 };
164
165 static int tmp102_probe(struct i2c_client *client,
166                                   const struct i2c_device_id *id)
167 {
168         struct device *dev = &client->dev;
169         struct device *hwmon_dev;
170         struct tmp102 *tmp102;
171         int status;
172
173         if (!i2c_check_functionality(client->adapter,
174                                      I2C_FUNC_SMBUS_WORD_DATA)) {
175                 dev_err(dev,
176                         "adapter doesn't support SMBus word transactions\n");
177                 return -ENODEV;
178         }
179
180         tmp102 = devm_kzalloc(dev, sizeof(*tmp102), GFP_KERNEL);
181         if (!tmp102)
182                 return -ENOMEM;
183
184         i2c_set_clientdata(client, tmp102);
185         tmp102->client = client;
186
187         status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
188         if (status < 0) {
189                 dev_err(dev, "error reading config register\n");
190                 return status;
191         }
192         tmp102->config_orig = status;
193         status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
194                                               TMP102_CONFIG);
195         if (status < 0) {
196                 dev_err(dev, "error writing config register\n");
197                 goto fail_restore_config;
198         }
199         status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
200         if (status < 0) {
201                 dev_err(dev, "error reading config register\n");
202                 goto fail_restore_config;
203         }
204         status &= ~TMP102_CONFIG_RD_ONLY;
205         if (status != TMP102_CONFIG) {
206                 dev_err(dev, "config settings did not stick\n");
207                 status = -ENODEV;
208                 goto fail_restore_config;
209         }
210         tmp102->last_update = jiffies - HZ;
211         mutex_init(&tmp102->lock);
212
213         hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
214                                                       tmp102, tmp102_groups);
215         if (IS_ERR(hwmon_dev)) {
216                 dev_dbg(dev, "unable to register hwmon device\n");
217                 status = PTR_ERR(hwmon_dev);
218                 goto fail_restore_config;
219         }
220         tmp102->hwmon_dev = hwmon_dev;
221         tmp102->tz = thermal_zone_of_sensor_register(hwmon_dev, 0, hwmon_dev,
222                                                      &tmp102_of_thermal_ops);
223         if (IS_ERR(tmp102->tz))
224                 tmp102->tz = NULL;
225
226         dev_info(dev, "initialized\n");
227
228         return 0;
229
230 fail_restore_config:
231         i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
232                                      tmp102->config_orig);
233         return status;
234 }
235
236 static int tmp102_remove(struct i2c_client *client)
237 {
238         struct tmp102 *tmp102 = i2c_get_clientdata(client);
239
240         thermal_zone_of_sensor_unregister(tmp102->hwmon_dev, tmp102->tz);
241         hwmon_device_unregister(tmp102->hwmon_dev);
242
243         /* Stop monitoring if device was stopped originally */
244         if (tmp102->config_orig & TMP102_CONF_SD) {
245                 int config;
246
247                 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
248                 if (config >= 0)
249                         i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
250                                                      config | TMP102_CONF_SD);
251         }
252
253         return 0;
254 }
255
256 #ifdef CONFIG_PM
257 static int tmp102_suspend(struct device *dev)
258 {
259         struct i2c_client *client = to_i2c_client(dev);
260         int config;
261
262         config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
263         if (config < 0)
264                 return config;
265
266         config |= TMP102_CONF_SD;
267         return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
268 }
269
270 static int tmp102_resume(struct device *dev)
271 {
272         struct i2c_client *client = to_i2c_client(dev);
273         int config;
274
275         config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
276         if (config < 0)
277                 return config;
278
279         config &= ~TMP102_CONF_SD;
280         return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
281 }
282
283 static const struct dev_pm_ops tmp102_dev_pm_ops = {
284         .suspend        = tmp102_suspend,
285         .resume         = tmp102_resume,
286 };
287
288 #define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
289 #else
290 #define TMP102_DEV_PM_OPS NULL
291 #endif /* CONFIG_PM */
292
293 static const struct i2c_device_id tmp102_id[] = {
294         { "tmp102", 0 },
295         { }
296 };
297 MODULE_DEVICE_TABLE(i2c, tmp102_id);
298
299 static struct i2c_driver tmp102_driver = {
300         .driver.name    = DRIVER_NAME,
301         .driver.pm      = TMP102_DEV_PM_OPS,
302         .probe          = tmp102_probe,
303         .remove         = tmp102_remove,
304         .id_table       = tmp102_id,
305 };
306
307 module_i2c_driver(tmp102_driver);
308
309 MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
310 MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
311 MODULE_LICENSE("GPL");