xref: /openbmc/linux/drivers/iio/adc/axp288_adc.c (revision e5c86679)
1 /*
2  * axp288_adc.c - X-Powers AXP288 PMIC ADC Driver
3  *
4  * Copyright (C) 2014 Intel Corporation
5  *
6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; version 2 of the License.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the GNU
15  * General Public License for more details.
16  *
17  */
18 
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/device.h>
22 #include <linux/regmap.h>
23 #include <linux/mfd/axp20x.h>
24 #include <linux/platform_device.h>
25 
26 #include <linux/iio/iio.h>
27 #include <linux/iio/machine.h>
28 #include <linux/iio/driver.h>
29 
30 #define AXP288_ADC_EN_MASK		0xF1
31 
32 enum axp288_adc_id {
33 	AXP288_ADC_TS,
34 	AXP288_ADC_PMIC,
35 	AXP288_ADC_GP,
36 	AXP288_ADC_BATT_CHRG_I,
37 	AXP288_ADC_BATT_DISCHRG_I,
38 	AXP288_ADC_BATT_V,
39 	AXP288_ADC_NR_CHAN,
40 };
41 
42 struct axp288_adc_info {
43 	int irq;
44 	struct regmap *regmap;
45 };
46 
47 static const struct iio_chan_spec axp288_adc_channels[] = {
48 	{
49 		.indexed = 1,
50 		.type = IIO_TEMP,
51 		.channel = 0,
52 		.address = AXP288_TS_ADC_H,
53 		.datasheet_name = "TS_PIN",
54 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
55 	}, {
56 		.indexed = 1,
57 		.type = IIO_TEMP,
58 		.channel = 1,
59 		.address = AXP288_PMIC_ADC_H,
60 		.datasheet_name = "PMIC_TEMP",
61 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
62 	}, {
63 		.indexed = 1,
64 		.type = IIO_TEMP,
65 		.channel = 2,
66 		.address = AXP288_GP_ADC_H,
67 		.datasheet_name = "GPADC",
68 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
69 	}, {
70 		.indexed = 1,
71 		.type = IIO_CURRENT,
72 		.channel = 3,
73 		.address = AXP20X_BATT_CHRG_I_H,
74 		.datasheet_name = "BATT_CHG_I",
75 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
76 	}, {
77 		.indexed = 1,
78 		.type = IIO_CURRENT,
79 		.channel = 4,
80 		.address = AXP20X_BATT_DISCHRG_I_H,
81 		.datasheet_name = "BATT_DISCHRG_I",
82 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
83 	}, {
84 		.indexed = 1,
85 		.type = IIO_VOLTAGE,
86 		.channel = 5,
87 		.address = AXP20X_BATT_V_H,
88 		.datasheet_name = "BATT_V",
89 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
90 	},
91 };
92 
93 #define AXP288_ADC_MAP(_adc_channel_label, _consumer_dev_name,	\
94 		_consumer_channel)				\
95 	{							\
96 		.adc_channel_label = _adc_channel_label,	\
97 		.consumer_dev_name = _consumer_dev_name,	\
98 		.consumer_channel = _consumer_channel,		\
99 	}
100 
101 /* for consumer drivers */
102 static struct iio_map axp288_adc_default_maps[] = {
103 	AXP288_ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
104 	AXP288_ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
105 	AXP288_ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
106 	AXP288_ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
107 	AXP288_ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
108 	AXP288_ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
109 	{},
110 };
111 
112 static int axp288_adc_read_channel(int *val, unsigned long address,
113 				struct regmap *regmap)
114 {
115 	u8 buf[2];
116 
117 	if (regmap_bulk_read(regmap, address, buf, 2))
118 		return -EIO;
119 	*val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F);
120 
121 	return IIO_VAL_INT;
122 }
123 
124 static int axp288_adc_read_raw(struct iio_dev *indio_dev,
125 			struct iio_chan_spec const *chan,
126 			int *val, int *val2, long mask)
127 {
128 	int ret;
129 	struct axp288_adc_info *info = iio_priv(indio_dev);
130 
131 	mutex_lock(&indio_dev->mlock);
132 	switch (mask) {
133 	case IIO_CHAN_INFO_RAW:
134 		ret = axp288_adc_read_channel(val, chan->address, info->regmap);
135 		break;
136 	default:
137 		ret = -EINVAL;
138 	}
139 	mutex_unlock(&indio_dev->mlock);
140 
141 	return ret;
142 }
143 
144 static const struct iio_info axp288_adc_iio_info = {
145 	.read_raw = &axp288_adc_read_raw,
146 	.driver_module = THIS_MODULE,
147 };
148 
149 static int axp288_adc_probe(struct platform_device *pdev)
150 {
151 	int ret;
152 	struct axp288_adc_info *info;
153 	struct iio_dev *indio_dev;
154 	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
155 
156 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
157 	if (!indio_dev)
158 		return -ENOMEM;
159 
160 	info = iio_priv(indio_dev);
161 	info->irq = platform_get_irq(pdev, 0);
162 	if (info->irq < 0) {
163 		dev_err(&pdev->dev, "no irq resource?\n");
164 		return info->irq;
165 	}
166 	platform_set_drvdata(pdev, indio_dev);
167 	info->regmap = axp20x->regmap;
168 	/*
169 	 * Set ADC to enabled state at all time, including system suspend.
170 	 * otherwise internal fuel gauge functionality may be affected.
171 	 */
172 	ret = regmap_write(info->regmap, AXP20X_ADC_EN1, AXP288_ADC_EN_MASK);
173 	if (ret) {
174 		dev_err(&pdev->dev, "unable to enable ADC device\n");
175 		return ret;
176 	}
177 
178 	indio_dev->dev.parent = &pdev->dev;
179 	indio_dev->name = pdev->name;
180 	indio_dev->channels = axp288_adc_channels;
181 	indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels);
182 	indio_dev->info = &axp288_adc_iio_info;
183 	indio_dev->modes = INDIO_DIRECT_MODE;
184 	ret = iio_map_array_register(indio_dev, axp288_adc_default_maps);
185 	if (ret < 0)
186 		return ret;
187 
188 	ret = iio_device_register(indio_dev);
189 	if (ret < 0) {
190 		dev_err(&pdev->dev, "unable to register iio device\n");
191 		goto err_array_unregister;
192 	}
193 	return 0;
194 
195 err_array_unregister:
196 	iio_map_array_unregister(indio_dev);
197 
198 	return ret;
199 }
200 
201 static int axp288_adc_remove(struct platform_device *pdev)
202 {
203 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
204 
205 	iio_device_unregister(indio_dev);
206 	iio_map_array_unregister(indio_dev);
207 
208 	return 0;
209 }
210 
211 static const struct platform_device_id axp288_adc_id_table[] = {
212 	{ .name = "axp288_adc" },
213 	{},
214 };
215 
216 static struct platform_driver axp288_adc_driver = {
217 	.probe = axp288_adc_probe,
218 	.remove = axp288_adc_remove,
219 	.id_table = axp288_adc_id_table,
220 	.driver = {
221 		.name = "axp288_adc",
222 	},
223 };
224 
225 MODULE_DEVICE_TABLE(platform, axp288_adc_id_table);
226 
227 module_platform_driver(axp288_adc_driver);
228 
229 MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@linux.intel.com>");
230 MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver");
231 MODULE_LICENSE("GPL");
232