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da9052-hwmon.c
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1 /*
2  * HWMON Driver for Dialog DA9052
3  *
4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
5  *
6  * Author: David Dajun Chen <[email protected]>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License as published by the
10  * Free Software Foundation; either version 2 of the License, or (at your
11  * option) any later version.
12  *
13  */
14 
15 #include <linux/err.h>
16 #include <linux/hwmon.h>
17 #include <linux/hwmon-sysfs.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/slab.h>
22 #include <linux/platform_device.h>
23 
24 #include <linux/mfd/da9052/da9052.h>
25 #include <linux/mfd/da9052/reg.h>
26 
27 struct da9052_hwmon {
28  struct da9052 *da9052;
29  struct device *class_device;
30  struct mutex hwmon_lock;
31 };
32 
33 static const char * const input_names[] = {
34  [DA9052_ADC_VDDOUT] = "VDDOUT",
35  [DA9052_ADC_ICH] = "CHARGING CURRENT",
36  [DA9052_ADC_TBAT] = "BATTERY TEMP",
37  [DA9052_ADC_VBAT] = "BATTERY VOLTAGE",
38  [DA9052_ADC_IN4] = "ADC IN4",
39  [DA9052_ADC_IN5] = "ADC IN5",
40  [DA9052_ADC_IN6] = "ADC IN6",
41  [DA9052_ADC_TJUNC] = "BATTERY JUNCTION TEMP",
42  [DA9052_ADC_VBBAT] = "BACK-UP BATTERY VOLTAGE",
43 };
44 
45 /* Conversion function for VDDOUT and VBAT */
46 static inline int volt_reg_to_mV(int value)
47 {
48  return DIV_ROUND_CLOSEST(value * 1000, 512) + 2500;
49 }
50 
51 /* Conversion function for ADC channels 4, 5 and 6 */
52 static inline int input_reg_to_mV(int value)
53 {
54  return DIV_ROUND_CLOSEST(value * 2500, 1023);
55 }
56 
57 /* Conversion function for VBBAT */
58 static inline int vbbat_reg_to_mV(int value)
59 {
60  return DIV_ROUND_CLOSEST(value * 2500, 512);
61 }
62 
63 static int da9052_enable_vddout_channel(struct da9052 *da9052)
64 {
65  int ret;
66 
67  ret = da9052_reg_read(da9052, DA9052_ADC_CONT_REG);
68  if (ret < 0)
69  return ret;
70 
71  ret |= DA9052_ADCCONT_AUTOVDDEN;
72 
73  return da9052_reg_write(da9052, DA9052_ADC_CONT_REG, ret);
74 }
75 
76 static int da9052_disable_vddout_channel(struct da9052 *da9052)
77 {
78  int ret;
79 
80  ret = da9052_reg_read(da9052, DA9052_ADC_CONT_REG);
81  if (ret < 0)
82  return ret;
83 
84  ret &= ~DA9052_ADCCONT_AUTOVDDEN;
85 
86  return da9052_reg_write(da9052, DA9052_ADC_CONT_REG, ret);
87 }
88 
89 static ssize_t da9052_read_vddout(struct device *dev,
90  struct device_attribute *devattr, char *buf)
91 {
92  struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
93  int ret, vdd;
94 
95  mutex_lock(&hwmon->hwmon_lock);
96 
97  ret = da9052_enable_vddout_channel(hwmon->da9052);
98  if (ret < 0)
99  goto hwmon_err;
100 
101  vdd = da9052_reg_read(hwmon->da9052, DA9052_VDD_RES_REG);
102  if (vdd < 0) {
103  ret = vdd;
104  goto hwmon_err_release;
105  }
106 
107  ret = da9052_disable_vddout_channel(hwmon->da9052);
108  if (ret < 0)
109  goto hwmon_err;
110 
111  mutex_unlock(&hwmon->hwmon_lock);
112  return sprintf(buf, "%d\n", volt_reg_to_mV(vdd));
113 
114 hwmon_err_release:
115  da9052_disable_vddout_channel(hwmon->da9052);
116 hwmon_err:
117  mutex_unlock(&hwmon->hwmon_lock);
118  return ret;
119 }
120 
121 static ssize_t da9052_read_ich(struct device *dev,
122  struct device_attribute *devattr, char *buf)
123 {
124  struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
125  int ret;
126 
127  ret = da9052_reg_read(hwmon->da9052, DA9052_ICHG_AV_REG);
128  if (ret < 0)
129  return ret;
130 
131  /* Equivalent to 3.9mA/bit in register ICHG_AV */
132  return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(ret * 39, 10));
133 }
134 
135 static ssize_t da9052_read_tbat(struct device *dev,
136  struct device_attribute *devattr, char *buf)
137 {
138  struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
139 
140  return sprintf(buf, "%d\n", da9052_adc_read_temp(hwmon->da9052));
141 }
142 
143 static ssize_t da9052_read_vbat(struct device *dev,
144  struct device_attribute *devattr, char *buf)
145 {
146  struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
147  int ret;
148 
149  ret = da9052_adc_manual_read(hwmon->da9052, DA9052_ADC_VBAT);
150  if (ret < 0)
151  return ret;
152 
153  return sprintf(buf, "%d\n", volt_reg_to_mV(ret));
154 }
155 
156 static ssize_t da9052_read_misc_channel(struct device *dev,
157  struct device_attribute *devattr,
158  char *buf)
159 {
160  struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
161  int channel = to_sensor_dev_attr(devattr)->index;
162  int ret;
163 
164  ret = da9052_adc_manual_read(hwmon->da9052, channel);
165  if (ret < 0)
166  return ret;
167 
168  return sprintf(buf, "%d\n", input_reg_to_mV(ret));
169 }
170 
171 static ssize_t da9052_read_tjunc(struct device *dev,
172  struct device_attribute *devattr, char *buf)
173 {
174  struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
175  int tjunc;
176  int toffset;
177 
178  tjunc = da9052_reg_read(hwmon->da9052, DA9052_TJUNC_RES_REG);
179  if (tjunc < 0)
180  return tjunc;
181 
182  toffset = da9052_reg_read(hwmon->da9052, DA9052_T_OFFSET_REG);
183  if (toffset < 0)
184  return toffset;
185 
186  /*
187  * Degrees celsius = 1.708 * (TJUNC_RES - T_OFFSET) - 108.8
188  * T_OFFSET is a trim value used to improve accuracy of the result
189  */
190  return sprintf(buf, "%d\n", 1708 * (tjunc - toffset) - 108800);
191 }
192 
193 static ssize_t da9052_read_vbbat(struct device *dev,
194  struct device_attribute *devattr, char *buf)
195 {
196  struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
197  int ret;
198 
199  ret = da9052_adc_manual_read(hwmon->da9052, DA9052_ADC_VBBAT);
200  if (ret < 0)
201  return ret;
202 
203  return sprintf(buf, "%d\n", vbbat_reg_to_mV(ret));
204 }
205 
206 static ssize_t da9052_hwmon_show_name(struct device *dev,
207  struct device_attribute *devattr,
208  char *buf)
209 {
210  return sprintf(buf, "da9052-hwmon\n");
211 }
212 
213 static ssize_t show_label(struct device *dev,
214  struct device_attribute *devattr, char *buf)
215 {
216  return sprintf(buf, "%s\n",
217  input_names[to_sensor_dev_attr(devattr)->index]);
218 }
219 
220 static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, da9052_read_vddout, NULL,
221  DA9052_ADC_VDDOUT);
222 static SENSOR_DEVICE_ATTR(in0_label, S_IRUGO, show_label, NULL,
223  DA9052_ADC_VDDOUT);
224 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, da9052_read_vbat, NULL,
225  DA9052_ADC_VBAT);
226 static SENSOR_DEVICE_ATTR(in3_label, S_IRUGO, show_label, NULL,
227  DA9052_ADC_VBAT);
228 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, da9052_read_misc_channel, NULL,
229  DA9052_ADC_IN4);
230 static SENSOR_DEVICE_ATTR(in4_label, S_IRUGO, show_label, NULL,
231  DA9052_ADC_IN4);
232 static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, da9052_read_misc_channel, NULL,
233  DA9052_ADC_IN5);
234 static SENSOR_DEVICE_ATTR(in5_label, S_IRUGO, show_label, NULL,
235  DA9052_ADC_IN5);
236 static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, da9052_read_misc_channel, NULL,
237  DA9052_ADC_IN6);
238 static SENSOR_DEVICE_ATTR(in6_label, S_IRUGO, show_label, NULL,
239  DA9052_ADC_IN6);
240 static SENSOR_DEVICE_ATTR(in9_input, S_IRUGO, da9052_read_vbbat, NULL,
241  DA9052_ADC_VBBAT);
242 static SENSOR_DEVICE_ATTR(in9_label, S_IRUGO, show_label, NULL,
243  DA9052_ADC_VBBAT);
244 
245 static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, da9052_read_ich, NULL,
246  DA9052_ADC_ICH);
247 static SENSOR_DEVICE_ATTR(curr1_label, S_IRUGO, show_label, NULL,
248  DA9052_ADC_ICH);
249 
250 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, da9052_read_tbat, NULL,
251  DA9052_ADC_TBAT);
252 static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, show_label, NULL,
253  DA9052_ADC_TBAT);
254 static SENSOR_DEVICE_ATTR(temp8_input, S_IRUGO, da9052_read_tjunc, NULL,
255  DA9052_ADC_TJUNC);
256 static SENSOR_DEVICE_ATTR(temp8_label, S_IRUGO, show_label, NULL,
257  DA9052_ADC_TJUNC);
258 
259 static DEVICE_ATTR(name, S_IRUGO, da9052_hwmon_show_name, NULL);
260 
261 static struct attribute *da9052_attr[] = {
262  &dev_attr_name.attr,
263  &sensor_dev_attr_in0_input.dev_attr.attr,
264  &sensor_dev_attr_in0_label.dev_attr.attr,
265  &sensor_dev_attr_in3_input.dev_attr.attr,
266  &sensor_dev_attr_in3_label.dev_attr.attr,
267  &sensor_dev_attr_in4_input.dev_attr.attr,
268  &sensor_dev_attr_in4_label.dev_attr.attr,
269  &sensor_dev_attr_in5_input.dev_attr.attr,
270  &sensor_dev_attr_in5_label.dev_attr.attr,
271  &sensor_dev_attr_in6_input.dev_attr.attr,
272  &sensor_dev_attr_in6_label.dev_attr.attr,
273  &sensor_dev_attr_in9_input.dev_attr.attr,
274  &sensor_dev_attr_in9_label.dev_attr.attr,
275  &sensor_dev_attr_curr1_input.dev_attr.attr,
276  &sensor_dev_attr_curr1_label.dev_attr.attr,
277  &sensor_dev_attr_temp2_input.dev_attr.attr,
278  &sensor_dev_attr_temp2_label.dev_attr.attr,
279  &sensor_dev_attr_temp8_input.dev_attr.attr,
280  &sensor_dev_attr_temp8_label.dev_attr.attr,
281  NULL
282 };
283 
284 static const struct attribute_group da9052_attr_group = {.attrs = da9052_attr};
285 
286 static int __devinit da9052_hwmon_probe(struct platform_device *pdev)
287 {
288  struct da9052_hwmon *hwmon;
289  int ret;
290 
291  hwmon = devm_kzalloc(&pdev->dev, sizeof(struct da9052_hwmon),
292  GFP_KERNEL);
293  if (!hwmon)
294  return -ENOMEM;
295 
296  mutex_init(&hwmon->hwmon_lock);
297  hwmon->da9052 = dev_get_drvdata(pdev->dev.parent);
298 
299  platform_set_drvdata(pdev, hwmon);
300 
301  ret = sysfs_create_group(&pdev->dev.kobj, &da9052_attr_group);
302  if (ret)
303  goto err_mem;
304 
305  hwmon->class_device = hwmon_device_register(&pdev->dev);
306  if (IS_ERR(hwmon->class_device)) {
307  ret = PTR_ERR(hwmon->class_device);
308  goto err_sysfs;
309  }
310 
311  return 0;
312 
313 err_sysfs:
314  sysfs_remove_group(&pdev->dev.kobj, &da9052_attr_group);
315 err_mem:
316  return ret;
317 }
318 
319 static int __devexit da9052_hwmon_remove(struct platform_device *pdev)
320 {
321  struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);
322 
323  hwmon_device_unregister(hwmon->class_device);
324  sysfs_remove_group(&pdev->dev.kobj, &da9052_attr_group);
325 
326  return 0;
327 }
328 
329 static struct platform_driver da9052_hwmon_driver = {
330  .probe = da9052_hwmon_probe,
331  .remove = __devexit_p(da9052_hwmon_remove),
332  .driver = {
333  .name = "da9052-hwmon",
334  .owner = THIS_MODULE,
335  },
336 };
337 
338 module_platform_driver(da9052_hwmon_driver);
339 
340 MODULE_AUTHOR("David Dajun Chen <[email protected]>");
341 MODULE_DESCRIPTION("DA9052 HWMON driver");
342 MODULE_LICENSE("GPL");
343 MODULE_ALIAS("platform:da9052-hwmon");
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