xref: /linux/drivers/hwmon/da9055-hwmon.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * HWMON Driver for Dialog DA9055
3  *
4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
5  *
6  * Author: David Dajun Chen <dchen@diasemi.com>
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/delay.h>
16 #include <linux/err.h>
17 #include <linux/hwmon.h>
18 #include <linux/hwmon-sysfs.h>
19 #include <linux/init.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/completion.h>
24 
25 #include <linux/mfd/da9055/core.h>
26 #include <linux/mfd/da9055/reg.h>
27 
28 #define DA9055_ADCIN_DIV	102
29 #define DA9055_VSYS_DIV	85
30 
31 #define DA9055_ADC_VSYS	0
32 #define DA9055_ADC_ADCIN1	1
33 #define DA9055_ADC_ADCIN2	2
34 #define DA9055_ADC_ADCIN3	3
35 #define DA9055_ADC_TJUNC	4
36 
37 struct da9055_hwmon {
38 	struct da9055	*da9055;
39 	struct device	*class_device;
40 	struct mutex	hwmon_lock;
41 	struct mutex	irq_lock;
42 	struct completion done;
43 };
44 
45 static const char * const input_names[] = {
46 	[DA9055_ADC_VSYS]	= "VSYS",
47 	[DA9055_ADC_ADCIN1]	= "ADC IN1",
48 	[DA9055_ADC_ADCIN2]	= "ADC IN2",
49 	[DA9055_ADC_ADCIN3]	= "ADC IN3",
50 	[DA9055_ADC_TJUNC]	= "CHIP TEMP",
51 };
52 
53 static const u8 chan_mux[DA9055_ADC_TJUNC + 1] = {
54 	[DA9055_ADC_VSYS]	= DA9055_ADC_MUX_VSYS,
55 	[DA9055_ADC_ADCIN1]	= DA9055_ADC_MUX_ADCIN1,
56 	[DA9055_ADC_ADCIN2]	= DA9055_ADC_MUX_ADCIN2,
57 	[DA9055_ADC_ADCIN3]	= DA9055_ADC_MUX_ADCIN3,
58 	[DA9055_ADC_TJUNC]	= DA9055_ADC_MUX_T_SENSE,
59 };
60 
61 static int da9055_adc_manual_read(struct da9055_hwmon *hwmon,
62 					unsigned char channel)
63 {
64 	int ret;
65 	unsigned short calc_data;
66 	unsigned short data;
67 	unsigned char mux_sel;
68 	struct da9055 *da9055 = hwmon->da9055;
69 
70 	if (channel > DA9055_ADC_TJUNC)
71 		return -EINVAL;
72 
73 	mutex_lock(&hwmon->irq_lock);
74 
75 	/* Selects desired MUX for manual conversion */
76 	mux_sel = chan_mux[channel] | DA9055_ADC_MAN_CONV;
77 
78 	ret = da9055_reg_write(da9055, DA9055_REG_ADC_MAN, mux_sel);
79 	if (ret < 0)
80 		goto err;
81 
82 	/* Wait for an interrupt */
83 	if (!wait_for_completion_timeout(&hwmon->done,
84 					msecs_to_jiffies(500))) {
85 		dev_err(da9055->dev,
86 			"timeout waiting for ADC conversion interrupt\n");
87 		ret = -ETIMEDOUT;
88 		goto err;
89 	}
90 
91 	ret = da9055_reg_read(da9055, DA9055_REG_ADC_RES_H);
92 	if (ret < 0)
93 		goto err;
94 
95 	calc_data = (unsigned short)ret;
96 	data = calc_data << 2;
97 
98 	ret = da9055_reg_read(da9055, DA9055_REG_ADC_RES_L);
99 	if (ret < 0)
100 		goto err;
101 
102 	calc_data = (unsigned short)(ret & DA9055_ADC_LSB_MASK);
103 	data |= calc_data;
104 
105 	ret = data;
106 
107 err:
108 	mutex_unlock(&hwmon->irq_lock);
109 	return ret;
110 }
111 
112 static irqreturn_t da9055_auxadc_irq(int irq, void *irq_data)
113 {
114 	struct da9055_hwmon *hwmon = irq_data;
115 
116 	complete(&hwmon->done);
117 
118 	return IRQ_HANDLED;
119 }
120 
121 /* Conversion function for VSYS and ADCINx */
122 static inline int volt_reg_to_mV(int value, int channel)
123 {
124 	if (channel == DA9055_ADC_VSYS)
125 		return DIV_ROUND_CLOSEST(value * 1000, DA9055_VSYS_DIV) + 2500;
126 	else
127 		return DIV_ROUND_CLOSEST(value * 1000, DA9055_ADCIN_DIV);
128 }
129 
130 static int da9055_enable_auto_mode(struct da9055 *da9055, int channel)
131 {
132 
133 	return da9055_reg_update(da9055, DA9055_REG_ADC_CONT, 1 << channel,
134 				1 << channel);
135 
136 }
137 
138 static int da9055_disable_auto_mode(struct da9055 *da9055, int channel)
139 {
140 
141 	return da9055_reg_update(da9055, DA9055_REG_ADC_CONT, 1 << channel, 0);
142 }
143 
144 static ssize_t da9055_read_auto_ch(struct device *dev,
145 				struct device_attribute *devattr, char *buf)
146 {
147 	struct da9055_hwmon *hwmon = dev_get_drvdata(dev);
148 	int ret, adc;
149 	int channel = to_sensor_dev_attr(devattr)->index;
150 
151 	mutex_lock(&hwmon->hwmon_lock);
152 
153 	ret = da9055_enable_auto_mode(hwmon->da9055, channel);
154 	if (ret < 0)
155 		goto hwmon_err;
156 
157 	usleep_range(10000, 10500);
158 
159 	adc = da9055_reg_read(hwmon->da9055, DA9055_REG_VSYS_RES + channel);
160 	if (adc < 0) {
161 		ret = adc;
162 		goto hwmon_err_release;
163 	}
164 
165 	ret = da9055_disable_auto_mode(hwmon->da9055, channel);
166 	if (ret < 0)
167 		goto hwmon_err;
168 
169 	mutex_unlock(&hwmon->hwmon_lock);
170 
171 	return sprintf(buf, "%d\n", volt_reg_to_mV(adc, channel));
172 
173 hwmon_err_release:
174 	da9055_disable_auto_mode(hwmon->da9055, channel);
175 hwmon_err:
176 	mutex_unlock(&hwmon->hwmon_lock);
177 	return ret;
178 }
179 
180 static ssize_t da9055_read_tjunc(struct device *dev,
181 				 struct device_attribute *devattr, char *buf)
182 {
183 	struct da9055_hwmon *hwmon = dev_get_drvdata(dev);
184 	int tjunc;
185 	int toffset;
186 
187 	tjunc = da9055_adc_manual_read(hwmon, DA9055_ADC_TJUNC);
188 	if (tjunc < 0)
189 		return tjunc;
190 
191 	toffset = da9055_reg_read(hwmon->da9055, DA9055_REG_T_OFFSET);
192 	if (toffset < 0)
193 		return toffset;
194 
195 	/*
196 	 * Degrees celsius = -0.4084 * (ADC_RES - T_OFFSET) + 307.6332
197 	 * T_OFFSET is a trim value used to improve accuracy of the result
198 	 */
199 	return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(-4084 * (tjunc - toffset)
200 							+ 3076332, 10000));
201 }
202 
203 static ssize_t da9055_hwmon_show_name(struct device *dev,
204 				      struct device_attribute *devattr,
205 				      char *buf)
206 {
207 	return sprintf(buf, "da9055-hwmon\n");
208 }
209 
210 static ssize_t show_label(struct device *dev,
211 			  struct device_attribute *devattr, char *buf)
212 {
213 	return sprintf(buf, "%s\n",
214 		       input_names[to_sensor_dev_attr(devattr)->index]);
215 }
216 
217 static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, da9055_read_auto_ch, NULL,
218 			  DA9055_ADC_VSYS);
219 static SENSOR_DEVICE_ATTR(in0_label, S_IRUGO, show_label, NULL,
220 			  DA9055_ADC_VSYS);
221 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, da9055_read_auto_ch, NULL,
222 			  DA9055_ADC_ADCIN1);
223 static SENSOR_DEVICE_ATTR(in1_label, S_IRUGO, show_label, NULL,
224 			  DA9055_ADC_ADCIN1);
225 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, da9055_read_auto_ch, NULL,
226 			  DA9055_ADC_ADCIN2);
227 static SENSOR_DEVICE_ATTR(in2_label, S_IRUGO, show_label, NULL,
228 			  DA9055_ADC_ADCIN2);
229 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, da9055_read_auto_ch, NULL,
230 			  DA9055_ADC_ADCIN3);
231 static SENSOR_DEVICE_ATTR(in3_label, S_IRUGO, show_label, NULL,
232 			  DA9055_ADC_ADCIN3);
233 
234 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, da9055_read_tjunc, NULL,
235 			  DA9055_ADC_TJUNC);
236 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL,
237 			  DA9055_ADC_TJUNC);
238 
239 static DEVICE_ATTR(name, S_IRUGO, da9055_hwmon_show_name, NULL);
240 
241 static struct attribute *da9055_attr[] = {
242 	&dev_attr_name.attr,
243 	&sensor_dev_attr_in0_input.dev_attr.attr,
244 	&sensor_dev_attr_in0_label.dev_attr.attr,
245 	&sensor_dev_attr_in1_input.dev_attr.attr,
246 	&sensor_dev_attr_in1_label.dev_attr.attr,
247 	&sensor_dev_attr_in2_input.dev_attr.attr,
248 	&sensor_dev_attr_in2_label.dev_attr.attr,
249 	&sensor_dev_attr_in3_input.dev_attr.attr,
250 	&sensor_dev_attr_in3_label.dev_attr.attr,
251 
252 	&sensor_dev_attr_temp1_input.dev_attr.attr,
253 	&sensor_dev_attr_temp1_label.dev_attr.attr,
254 	NULL
255 };
256 
257 static const struct attribute_group da9055_attr_group = {.attrs = da9055_attr};
258 
259 static int da9055_hwmon_probe(struct platform_device *pdev)
260 {
261 	struct da9055_hwmon *hwmon;
262 	int hwmon_irq, ret;
263 
264 	hwmon = devm_kzalloc(&pdev->dev, sizeof(struct da9055_hwmon),
265 			     GFP_KERNEL);
266 	if (!hwmon)
267 		return -ENOMEM;
268 
269 	mutex_init(&hwmon->hwmon_lock);
270 	mutex_init(&hwmon->irq_lock);
271 
272 	init_completion(&hwmon->done);
273 	hwmon->da9055 = dev_get_drvdata(pdev->dev.parent);
274 
275 	platform_set_drvdata(pdev, hwmon);
276 
277 	hwmon_irq = platform_get_irq_byname(pdev, "HWMON");
278 	if (hwmon_irq < 0)
279 		return hwmon_irq;
280 
281 	hwmon_irq = regmap_irq_get_virq(hwmon->da9055->irq_data, hwmon_irq);
282 	if (hwmon_irq < 0)
283 		return hwmon_irq;
284 
285 	ret = devm_request_threaded_irq(&pdev->dev, hwmon_irq,
286 					NULL, da9055_auxadc_irq,
287 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
288 					"adc-irq", hwmon);
289 	if (ret != 0) {
290 		dev_err(hwmon->da9055->dev, "DA9055 ADC IRQ failed ret=%d\n",
291 			ret);
292 		return ret;
293 	}
294 
295 	ret = sysfs_create_group(&pdev->dev.kobj, &da9055_attr_group);
296 	if (ret)
297 		return ret;
298 
299 	hwmon->class_device = hwmon_device_register(&pdev->dev);
300 	if (IS_ERR(hwmon->class_device)) {
301 		ret = PTR_ERR(hwmon->class_device);
302 		goto err;
303 	}
304 
305 	return 0;
306 
307 err:
308 	sysfs_remove_group(&pdev->dev.kobj, &da9055_attr_group);
309 	return ret;
310 }
311 
312 static int da9055_hwmon_remove(struct platform_device *pdev)
313 {
314 	struct da9055_hwmon *hwmon = platform_get_drvdata(pdev);
315 
316 	sysfs_remove_group(&pdev->dev.kobj, &da9055_attr_group);
317 	hwmon_device_unregister(hwmon->class_device);
318 
319 	return 0;
320 }
321 
322 static struct platform_driver da9055_hwmon_driver = {
323 	.probe = da9055_hwmon_probe,
324 	.remove = da9055_hwmon_remove,
325 	.driver = {
326 		.name = "da9055-hwmon",
327 		.owner = THIS_MODULE,
328 	},
329 };
330 
331 module_platform_driver(da9055_hwmon_driver);
332 
333 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
334 MODULE_DESCRIPTION("DA9055 HWMON driver");
335 MODULE_LICENSE("GPL");
336 MODULE_ALIAS("platform:da9055-hwmon");
337