1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (c) 2022 Analog Devices, Inc. |
4 | * ADI MAX77541 ADC Driver with IIO interface |
5 | */ |
6 | |
7 | #include <linux/bitfield.h> |
8 | #include <linux/iio/iio.h> |
9 | #include <linux/mod_devicetable.h> |
10 | #include <linux/platform_device.h> |
11 | #include <linux/regmap.h> |
12 | #include <linux/units.h> |
13 | |
14 | #include <linux/mfd/max77541.h> |
15 | |
16 | enum max77541_adc_range { |
17 | LOW_RANGE, |
18 | MID_RANGE, |
19 | HIGH_RANGE, |
20 | }; |
21 | |
22 | enum max77541_adc_channel { |
23 | MAX77541_ADC_VSYS_V, |
24 | MAX77541_ADC_VOUT1_V, |
25 | MAX77541_ADC_VOUT2_V, |
26 | MAX77541_ADC_TEMP, |
27 | }; |
28 | |
29 | static int max77541_adc_offset(struct iio_dev *indio_dev, |
30 | struct iio_chan_spec const *chan, |
31 | int *val, int *val2) |
32 | { |
33 | switch (chan->channel) { |
34 | case MAX77541_ADC_TEMP: |
35 | *val = DIV_ROUND_CLOSEST(ABSOLUTE_ZERO_MILLICELSIUS, 1725); |
36 | return IIO_VAL_INT; |
37 | default: |
38 | return -EINVAL; |
39 | } |
40 | } |
41 | |
42 | static int max77541_adc_scale(struct iio_dev *indio_dev, |
43 | struct iio_chan_spec const *chan, |
44 | int *val, int *val2) |
45 | { |
46 | struct regmap **regmap = iio_priv(indio_dev); |
47 | unsigned int reg_val; |
48 | int ret; |
49 | |
50 | switch (chan->channel) { |
51 | case MAX77541_ADC_VSYS_V: |
52 | *val = 25; |
53 | return IIO_VAL_INT; |
54 | case MAX77541_ADC_VOUT1_V: |
55 | case MAX77541_ADC_VOUT2_V: |
56 | ret = regmap_read(map: *regmap, MAX77541_REG_M2_CFG1, val: ®_val); |
57 | if (ret) |
58 | return ret; |
59 | |
60 | reg_val = FIELD_GET(MAX77541_BITS_MX_CFG1_RNG, reg_val); |
61 | switch (reg_val) { |
62 | case LOW_RANGE: |
63 | *val = 6; |
64 | *val2 = 250000; |
65 | break; |
66 | case MID_RANGE: |
67 | *val = 12; |
68 | *val2 = 500000; |
69 | break; |
70 | case HIGH_RANGE: |
71 | *val = 25; |
72 | return IIO_VAL_INT; |
73 | default: |
74 | return -EINVAL; |
75 | } |
76 | |
77 | return IIO_VAL_INT_PLUS_MICRO; |
78 | case MAX77541_ADC_TEMP: |
79 | *val = 1725; |
80 | return IIO_VAL_INT; |
81 | default: |
82 | return -EINVAL; |
83 | } |
84 | } |
85 | |
86 | static int max77541_adc_raw(struct iio_dev *indio_dev, |
87 | struct iio_chan_spec const *chan, |
88 | int *val) |
89 | { |
90 | struct regmap **regmap = iio_priv(indio_dev); |
91 | int ret; |
92 | |
93 | ret = regmap_read(map: *regmap, reg: chan->address, val); |
94 | if (ret) |
95 | return ret; |
96 | |
97 | return IIO_VAL_INT; |
98 | } |
99 | |
100 | #define MAX77541_ADC_CHANNEL_V(_channel, _name, _type, _reg) \ |
101 | { \ |
102 | .type = _type, \ |
103 | .indexed = 1, \ |
104 | .channel = _channel, \ |
105 | .address = _reg, \ |
106 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ |
107 | BIT(IIO_CHAN_INFO_SCALE), \ |
108 | .datasheet_name = _name, \ |
109 | } |
110 | |
111 | #define MAX77541_ADC_CHANNEL_TEMP(_channel, _name, _type, _reg) \ |
112 | { \ |
113 | .type = _type, \ |
114 | .indexed = 1, \ |
115 | .channel = _channel, \ |
116 | .address = _reg, \ |
117 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ |
118 | BIT(IIO_CHAN_INFO_SCALE) |\ |
119 | BIT(IIO_CHAN_INFO_OFFSET),\ |
120 | .datasheet_name = _name, \ |
121 | } |
122 | |
123 | static const struct iio_chan_spec max77541_adc_channels[] = { |
124 | MAX77541_ADC_CHANNEL_V(MAX77541_ADC_VSYS_V, "vsys_v" , IIO_VOLTAGE, |
125 | MAX77541_REG_ADC_DATA_CH1), |
126 | MAX77541_ADC_CHANNEL_V(MAX77541_ADC_VOUT1_V, "vout1_v" , IIO_VOLTAGE, |
127 | MAX77541_REG_ADC_DATA_CH2), |
128 | MAX77541_ADC_CHANNEL_V(MAX77541_ADC_VOUT2_V, "vout2_v" , IIO_VOLTAGE, |
129 | MAX77541_REG_ADC_DATA_CH3), |
130 | MAX77541_ADC_CHANNEL_TEMP(MAX77541_ADC_TEMP, "temp" , IIO_TEMP, |
131 | MAX77541_REG_ADC_DATA_CH6), |
132 | }; |
133 | |
134 | static int max77541_adc_read_raw(struct iio_dev *indio_dev, |
135 | struct iio_chan_spec const *chan, |
136 | int *val, int *val2, long mask) |
137 | { |
138 | switch (mask) { |
139 | case IIO_CHAN_INFO_OFFSET: |
140 | return max77541_adc_offset(indio_dev, chan, val, val2); |
141 | case IIO_CHAN_INFO_SCALE: |
142 | return max77541_adc_scale(indio_dev, chan, val, val2); |
143 | case IIO_CHAN_INFO_RAW: |
144 | return max77541_adc_raw(indio_dev, chan, val); |
145 | default: |
146 | return -EINVAL; |
147 | } |
148 | } |
149 | |
150 | static const struct iio_info max77541_adc_info = { |
151 | .read_raw = max77541_adc_read_raw, |
152 | }; |
153 | |
154 | static int max77541_adc_probe(struct platform_device *pdev) |
155 | { |
156 | struct device *dev = &pdev->dev; |
157 | struct iio_dev *indio_dev; |
158 | struct regmap **regmap; |
159 | |
160 | indio_dev = devm_iio_device_alloc(parent: dev, sizeof_priv: sizeof(*regmap)); |
161 | if (!indio_dev) |
162 | return -ENOMEM; |
163 | |
164 | regmap = iio_priv(indio_dev); |
165 | |
166 | *regmap = dev_get_regmap(dev: dev->parent, NULL); |
167 | indio_dev->modes = INDIO_DIRECT_MODE; |
168 | |
169 | indio_dev->name = "max77541" ; |
170 | indio_dev->info = &max77541_adc_info; |
171 | indio_dev->channels = max77541_adc_channels; |
172 | indio_dev->num_channels = ARRAY_SIZE(max77541_adc_channels); |
173 | |
174 | return devm_iio_device_register(dev, indio_dev); |
175 | } |
176 | |
177 | static const struct platform_device_id max77541_adc_platform_id[] = { |
178 | { "max77541-adc" }, |
179 | { /* sentinel */ } |
180 | }; |
181 | MODULE_DEVICE_TABLE(platform, max77541_adc_platform_id); |
182 | |
183 | static struct platform_driver max77541_adc_driver = { |
184 | .driver = { |
185 | .name = "max77541-adc" , |
186 | }, |
187 | .probe = max77541_adc_probe, |
188 | .id_table = max77541_adc_platform_id, |
189 | }; |
190 | module_platform_driver(max77541_adc_driver); |
191 | |
192 | MODULE_AUTHOR("Okan Sahin <Okan.Sahin@analog.com>" ); |
193 | MODULE_DESCRIPTION("MAX77541 ADC driver" ); |
194 | MODULE_LICENSE("GPL" ); |
195 | |