xref: /openbmc/linux/drivers/hwmon/da9055-hwmon.c (revision fb574682)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * HWMON Driver for Dialog DA9055
4  *
5  * Copyright(c) 2012 Dialog Semiconductor Ltd.
6  *
7  * Author: David Dajun Chen <dchen@diasemi.com>
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/err.h>
12 #include <linux/hwmon.h>
13 #include <linux/hwmon-sysfs.h>
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/platform_device.h>
18 #include <linux/completion.h>
19 
20 #include <linux/mfd/da9055/core.h>
21 #include <linux/mfd/da9055/reg.h>
22 
23 #define DA9055_ADCIN_DIV	102
24 #define DA9055_VSYS_DIV	85
25 
26 #define DA9055_ADC_VSYS	0
27 #define DA9055_ADC_ADCIN1	1
28 #define DA9055_ADC_ADCIN2	2
29 #define DA9055_ADC_ADCIN3	3
30 #define DA9055_ADC_TJUNC	4
31 
32 struct da9055_hwmon {
33 	struct da9055	*da9055;
34 	struct mutex	hwmon_lock;
35 	struct mutex	irq_lock;
36 	struct completion done;
37 };
38 
39 static const char * const input_names[] = {
40 	[DA9055_ADC_VSYS]	= "VSYS",
41 	[DA9055_ADC_ADCIN1]	= "ADC IN1",
42 	[DA9055_ADC_ADCIN2]	= "ADC IN2",
43 	[DA9055_ADC_ADCIN3]	= "ADC IN3",
44 	[DA9055_ADC_TJUNC]	= "CHIP TEMP",
45 };
46 
47 static const u8 chan_mux[DA9055_ADC_TJUNC + 1] = {
48 	[DA9055_ADC_VSYS]	= DA9055_ADC_MUX_VSYS,
49 	[DA9055_ADC_ADCIN1]	= DA9055_ADC_MUX_ADCIN1,
50 	[DA9055_ADC_ADCIN2]	= DA9055_ADC_MUX_ADCIN2,
51 	[DA9055_ADC_ADCIN3]	= DA9055_ADC_MUX_ADCIN3,
52 	[DA9055_ADC_TJUNC]	= DA9055_ADC_MUX_T_SENSE,
53 };
54 
55 static int da9055_adc_manual_read(struct da9055_hwmon *hwmon,
56 					unsigned char channel)
57 {
58 	int ret;
59 	unsigned short calc_data;
60 	unsigned short data;
61 	unsigned char mux_sel;
62 	struct da9055 *da9055 = hwmon->da9055;
63 
64 	if (channel > DA9055_ADC_TJUNC)
65 		return -EINVAL;
66 
67 	mutex_lock(&hwmon->irq_lock);
68 
69 	/* Selects desired MUX for manual conversion */
70 	mux_sel = chan_mux[channel] | DA9055_ADC_MAN_CONV;
71 
72 	ret = da9055_reg_write(da9055, DA9055_REG_ADC_MAN, mux_sel);
73 	if (ret < 0)
74 		goto err;
75 
76 	/* Wait for an interrupt */
77 	if (!wait_for_completion_timeout(&hwmon->done,
78 					msecs_to_jiffies(500))) {
79 		dev_err(da9055->dev,
80 			"timeout waiting for ADC conversion interrupt\n");
81 		ret = -ETIMEDOUT;
82 		goto err;
83 	}
84 
85 	ret = da9055_reg_read(da9055, DA9055_REG_ADC_RES_H);
86 	if (ret < 0)
87 		goto err;
88 
89 	calc_data = (unsigned short)ret;
90 	data = calc_data << 2;
91 
92 	ret = da9055_reg_read(da9055, DA9055_REG_ADC_RES_L);
93 	if (ret < 0)
94 		goto err;
95 
96 	calc_data = (unsigned short)(ret & DA9055_ADC_LSB_MASK);
97 	data |= calc_data;
98 
99 	ret = data;
100 
101 err:
102 	mutex_unlock(&hwmon->irq_lock);
103 	return ret;
104 }
105 
106 static irqreturn_t da9055_auxadc_irq(int irq, void *irq_data)
107 {
108 	struct da9055_hwmon *hwmon = irq_data;
109 
110 	complete(&hwmon->done);
111 
112 	return IRQ_HANDLED;
113 }
114 
115 /* Conversion function for VSYS and ADCINx */
116 static inline int volt_reg_to_mv(int value, int channel)
117 {
118 	if (channel == DA9055_ADC_VSYS)
119 		return DIV_ROUND_CLOSEST(value * 1000, DA9055_VSYS_DIV) + 2500;
120 	else
121 		return DIV_ROUND_CLOSEST(value * 1000, DA9055_ADCIN_DIV);
122 }
123 
124 static int da9055_enable_auto_mode(struct da9055 *da9055, int channel)
125 {
126 
127 	return da9055_reg_update(da9055, DA9055_REG_ADC_CONT, 1 << channel,
128 				1 << channel);
129 
130 }
131 
132 static int da9055_disable_auto_mode(struct da9055 *da9055, int channel)
133 {
134 
135 	return da9055_reg_update(da9055, DA9055_REG_ADC_CONT, 1 << channel, 0);
136 }
137 
138 static ssize_t da9055_auto_ch_show(struct device *dev,
139 				   struct device_attribute *devattr,
140 				   char *buf)
141 {
142 	struct da9055_hwmon *hwmon = dev_get_drvdata(dev);
143 	int ret, adc;
144 	int channel = to_sensor_dev_attr(devattr)->index;
145 
146 	mutex_lock(&hwmon->hwmon_lock);
147 
148 	ret = da9055_enable_auto_mode(hwmon->da9055, channel);
149 	if (ret < 0)
150 		goto hwmon_err;
151 
152 	usleep_range(10000, 10500);
153 
154 	adc = da9055_reg_read(hwmon->da9055, DA9055_REG_VSYS_RES + channel);
155 	if (adc < 0) {
156 		ret = adc;
157 		goto hwmon_err_release;
158 	}
159 
160 	ret = da9055_disable_auto_mode(hwmon->da9055, channel);
161 	if (ret < 0)
162 		goto hwmon_err;
163 
164 	mutex_unlock(&hwmon->hwmon_lock);
165 
166 	return sprintf(buf, "%d\n", volt_reg_to_mv(adc, channel));
167 
168 hwmon_err_release:
169 	da9055_disable_auto_mode(hwmon->da9055, channel);
170 hwmon_err:
171 	mutex_unlock(&hwmon->hwmon_lock);
172 	return ret;
173 }
174 
175 static ssize_t da9055_tjunc_show(struct device *dev,
176 				 struct device_attribute *devattr, char *buf)
177 {
178 	struct da9055_hwmon *hwmon = dev_get_drvdata(dev);
179 	int tjunc;
180 	int toffset;
181 
182 	tjunc = da9055_adc_manual_read(hwmon, DA9055_ADC_TJUNC);
183 	if (tjunc < 0)
184 		return tjunc;
185 
186 	toffset = da9055_reg_read(hwmon->da9055, DA9055_REG_T_OFFSET);
187 	if (toffset < 0)
188 		return toffset;
189 
190 	/*
191 	 * Degrees celsius = -0.4084 * (ADC_RES - T_OFFSET) + 307.6332
192 	 * T_OFFSET is a trim value used to improve accuracy of the result
193 	 */
194 	return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(-4084 * (tjunc - toffset)
195 							+ 3076332, 10000));
196 }
197 
198 static ssize_t label_show(struct device *dev,
199 			  struct device_attribute *devattr, char *buf)
200 {
201 	return sprintf(buf, "%s\n",
202 		       input_names[to_sensor_dev_attr(devattr)->index]);
203 }
204 
205 static SENSOR_DEVICE_ATTR_RO(in0_input, da9055_auto_ch, DA9055_ADC_VSYS);
206 static SENSOR_DEVICE_ATTR_RO(in0_label, label, DA9055_ADC_VSYS);
207 static SENSOR_DEVICE_ATTR_RO(in1_input, da9055_auto_ch, DA9055_ADC_ADCIN1);
208 static SENSOR_DEVICE_ATTR_RO(in1_label, label, DA9055_ADC_ADCIN1);
209 static SENSOR_DEVICE_ATTR_RO(in2_input, da9055_auto_ch, DA9055_ADC_ADCIN2);
210 static SENSOR_DEVICE_ATTR_RO(in2_label, label, DA9055_ADC_ADCIN2);
211 static SENSOR_DEVICE_ATTR_RO(in3_input, da9055_auto_ch, DA9055_ADC_ADCIN3);
212 static SENSOR_DEVICE_ATTR_RO(in3_label, label, DA9055_ADC_ADCIN3);
213 
214 static SENSOR_DEVICE_ATTR_RO(temp1_input, da9055_tjunc, DA9055_ADC_TJUNC);
215 static SENSOR_DEVICE_ATTR_RO(temp1_label, label, DA9055_ADC_TJUNC);
216 
217 static struct attribute *da9055_attrs[] = {
218 	&sensor_dev_attr_in0_input.dev_attr.attr,
219 	&sensor_dev_attr_in0_label.dev_attr.attr,
220 	&sensor_dev_attr_in1_input.dev_attr.attr,
221 	&sensor_dev_attr_in1_label.dev_attr.attr,
222 	&sensor_dev_attr_in2_input.dev_attr.attr,
223 	&sensor_dev_attr_in2_label.dev_attr.attr,
224 	&sensor_dev_attr_in3_input.dev_attr.attr,
225 	&sensor_dev_attr_in3_label.dev_attr.attr,
226 
227 	&sensor_dev_attr_temp1_input.dev_attr.attr,
228 	&sensor_dev_attr_temp1_label.dev_attr.attr,
229 	NULL
230 };
231 
232 ATTRIBUTE_GROUPS(da9055);
233 
234 static int da9055_hwmon_probe(struct platform_device *pdev)
235 {
236 	struct device *dev = &pdev->dev;
237 	struct da9055_hwmon *hwmon;
238 	struct device *hwmon_dev;
239 	int hwmon_irq, ret;
240 
241 	hwmon = devm_kzalloc(dev, sizeof(struct da9055_hwmon), GFP_KERNEL);
242 	if (!hwmon)
243 		return -ENOMEM;
244 
245 	mutex_init(&hwmon->hwmon_lock);
246 	mutex_init(&hwmon->irq_lock);
247 
248 	init_completion(&hwmon->done);
249 	hwmon->da9055 = dev_get_drvdata(pdev->dev.parent);
250 
251 	hwmon_irq = platform_get_irq_byname(pdev, "HWMON");
252 	if (hwmon_irq < 0)
253 		return hwmon_irq;
254 
255 	ret = devm_request_threaded_irq(&pdev->dev, hwmon_irq,
256 					NULL, da9055_auxadc_irq,
257 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
258 					"adc-irq", hwmon);
259 	if (ret != 0) {
260 		dev_err(hwmon->da9055->dev, "DA9055 ADC IRQ failed ret=%d\n",
261 			ret);
262 		return ret;
263 	}
264 
265 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, "da9055",
266 							   hwmon,
267 							   da9055_groups);
268 	return PTR_ERR_OR_ZERO(hwmon_dev);
269 }
270 
271 static struct platform_driver da9055_hwmon_driver = {
272 	.probe = da9055_hwmon_probe,
273 	.driver = {
274 		.name = "da9055-hwmon",
275 	},
276 };
277 
278 module_platform_driver(da9055_hwmon_driver);
279 
280 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
281 MODULE_DESCRIPTION("DA9055 HWMON driver");
282 MODULE_LICENSE("GPL");
283 MODULE_ALIAS("platform:da9055-hwmon");
284