1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * MP2629 Driver for ADC
4 *
5 * Copyright 2020 Monolithic Power Systems, Inc
6 *
7 * Author: Saravanan Sekar <sravanhome@gmail.com>
8 */
9
10 #include <linux/iio/driver.h>
11 #include <linux/iio/iio.h>
12 #include <linux/iio/machine.h>
13 #include <linux/mfd/mp2629.h>
14 #include <linux/module.h>
15 #include <linux/mutex.h>
16 #include <linux/platform_device.h>
17 #include <linux/regmap.h>
18
19 #define MP2629_REG_ADC_CTRL 0x03
20 #define MP2629_REG_BATT_VOLT 0x0e
21 #define MP2629_REG_SYSTEM_VOLT 0x0f
22 #define MP2629_REG_INPUT_VOLT 0x11
23 #define MP2629_REG_BATT_CURRENT 0x12
24 #define MP2629_REG_INPUT_CURRENT 0x13
25
26 #define MP2629_ADC_START BIT(7)
27 #define MP2629_ADC_CONTINUOUS BIT(6)
28
29 #define MP2629_MAP(_mp, _mpc) IIO_MAP(#_mp, "mp2629_charger", "mp2629-"_mpc)
30
31 #define MP2629_ADC_CHAN(_ch, _type) { \
32 .type = _type, \
33 .indexed = 1, \
34 .datasheet_name = #_ch, \
35 .channel = MP2629_ ## _ch, \
36 .address = MP2629_REG_ ## _ch, \
37 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
38 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
39 }
40
41 struct mp2629_adc {
42 struct regmap *regmap;
43 struct device *dev;
44 };
45
46 static struct iio_chan_spec mp2629_channels[] = {
47 MP2629_ADC_CHAN(BATT_VOLT, IIO_VOLTAGE),
48 MP2629_ADC_CHAN(SYSTEM_VOLT, IIO_VOLTAGE),
49 MP2629_ADC_CHAN(INPUT_VOLT, IIO_VOLTAGE),
50 MP2629_ADC_CHAN(BATT_CURRENT, IIO_CURRENT),
51 MP2629_ADC_CHAN(INPUT_CURRENT, IIO_CURRENT)
52 };
53
54 static struct iio_map mp2629_adc_maps[] = {
55 MP2629_MAP(BATT_VOLT, "batt-volt"),
56 MP2629_MAP(SYSTEM_VOLT, "system-volt"),
57 MP2629_MAP(INPUT_VOLT, "input-volt"),
58 MP2629_MAP(BATT_CURRENT, "batt-current"),
59 MP2629_MAP(INPUT_CURRENT, "input-current")
60 };
61
mp2629_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)62 static int mp2629_read_raw(struct iio_dev *indio_dev,
63 struct iio_chan_spec const *chan,
64 int *val, int *val2, long mask)
65 {
66 struct mp2629_adc *info = iio_priv(indio_dev);
67 unsigned int rval;
68 int ret;
69
70 switch (mask) {
71 case IIO_CHAN_INFO_RAW:
72 ret = regmap_read(info->regmap, chan->address, &rval);
73 if (ret)
74 return ret;
75
76 if (chan->address == MP2629_INPUT_VOLT)
77 rval &= GENMASK(6, 0);
78 *val = rval;
79 return IIO_VAL_INT;
80
81 case IIO_CHAN_INFO_SCALE:
82 switch (chan->channel) {
83 case MP2629_BATT_VOLT:
84 case MP2629_SYSTEM_VOLT:
85 *val = 20;
86 return IIO_VAL_INT;
87
88 case MP2629_INPUT_VOLT:
89 *val = 60;
90 return IIO_VAL_INT;
91
92 case MP2629_BATT_CURRENT:
93 *val = 175;
94 *val2 = 10;
95 return IIO_VAL_FRACTIONAL;
96
97 case MP2629_INPUT_CURRENT:
98 *val = 133;
99 *val2 = 10;
100 return IIO_VAL_FRACTIONAL;
101
102 default:
103 return -EINVAL;
104 }
105
106 default:
107 return -EINVAL;
108 }
109 }
110
111 static const struct iio_info mp2629_adc_info = {
112 .read_raw = &mp2629_read_raw,
113 };
114
mp2629_adc_probe(struct platform_device * pdev)115 static int mp2629_adc_probe(struct platform_device *pdev)
116 {
117 struct device *dev = &pdev->dev;
118 struct mp2629_data *ddata = dev_get_drvdata(dev->parent);
119 struct mp2629_adc *info;
120 struct iio_dev *indio_dev;
121 int ret;
122
123 indio_dev = devm_iio_device_alloc(dev, sizeof(*info));
124 if (!indio_dev)
125 return -ENOMEM;
126
127 info = iio_priv(indio_dev);
128 info->regmap = ddata->regmap;
129 info->dev = dev;
130 platform_set_drvdata(pdev, indio_dev);
131
132 ret = regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,
133 MP2629_ADC_START | MP2629_ADC_CONTINUOUS,
134 MP2629_ADC_START | MP2629_ADC_CONTINUOUS);
135 if (ret) {
136 dev_err(dev, "adc enable fail: %d\n", ret);
137 return ret;
138 }
139
140 ret = iio_map_array_register(indio_dev, mp2629_adc_maps);
141 if (ret) {
142 dev_err(dev, "IIO maps register fail: %d\n", ret);
143 goto fail_disable;
144 }
145
146 indio_dev->name = "mp2629-adc";
147 indio_dev->channels = mp2629_channels;
148 indio_dev->num_channels = ARRAY_SIZE(mp2629_channels);
149 indio_dev->modes = INDIO_DIRECT_MODE;
150 indio_dev->info = &mp2629_adc_info;
151
152 ret = iio_device_register(indio_dev);
153 if (ret) {
154 dev_err(dev, "IIO device register fail: %d\n", ret);
155 goto fail_map_unregister;
156 }
157
158 return 0;
159
160 fail_map_unregister:
161 iio_map_array_unregister(indio_dev);
162
163 fail_disable:
164 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,
165 MP2629_ADC_CONTINUOUS, 0);
166 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,
167 MP2629_ADC_START, 0);
168
169 return ret;
170 }
171
mp2629_adc_remove(struct platform_device * pdev)172 static int mp2629_adc_remove(struct platform_device *pdev)
173 {
174 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
175 struct mp2629_adc *info = iio_priv(indio_dev);
176
177 iio_device_unregister(indio_dev);
178
179 iio_map_array_unregister(indio_dev);
180
181 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,
182 MP2629_ADC_CONTINUOUS, 0);
183 regmap_update_bits(info->regmap, MP2629_REG_ADC_CTRL,
184 MP2629_ADC_START, 0);
185
186 return 0;
187 }
188
189 static const struct of_device_id mp2629_adc_of_match[] = {
190 { .compatible = "mps,mp2629_adc"},
191 {}
192 };
193 MODULE_DEVICE_TABLE(of, mp2629_adc_of_match);
194
195 static struct platform_driver mp2629_adc_driver = {
196 .driver = {
197 .name = "mp2629_adc",
198 .of_match_table = mp2629_adc_of_match,
199 },
200 .probe = mp2629_adc_probe,
201 .remove = mp2629_adc_remove,
202 };
203 module_platform_driver(mp2629_adc_driver);
204
205 MODULE_AUTHOR("Saravanan Sekar <sravanhome@gmail.com>");
206 MODULE_DESCRIPTION("MP2629 ADC driver");
207 MODULE_LICENSE("GPL");
208