summaryrefslogtreecommitdiffstats
path: root/drivers/iio/adc/axp288_adc.c
blob: 7fd24949c0c14fb53cb3d6f37a8d1d6afa1c0f0e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
/*
 * axp288_adc.c - X-Powers AXP288 PMIC ADC Driver
 *
 * Copyright (C) 2014 Intel Corporation
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the GNU
 * General Public License for more details.
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/regmap.h>
#include <linux/mfd/axp20x.h>
#include <linux/platform_device.h>

#include <linux/iio/iio.h>
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>

#define AXP288_ADC_EN_MASK		0xF1
#define AXP288_ADC_TS_PIN_GPADC		0xF2
#define AXP288_ADC_TS_PIN_ON		0xF3

enum axp288_adc_id {
	AXP288_ADC_TS,
	AXP288_ADC_PMIC,
	AXP288_ADC_GP,
	AXP288_ADC_BATT_CHRG_I,
	AXP288_ADC_BATT_DISCHRG_I,
	AXP288_ADC_BATT_V,
	AXP288_ADC_NR_CHAN,
};

struct axp288_adc_info {
	int irq;
	struct regmap *regmap;
};

static const struct iio_chan_spec axp288_adc_channels[] = {
	{
		.indexed = 1,
		.type = IIO_TEMP,
		.channel = 0,
		.address = AXP288_TS_ADC_H,
		.datasheet_name = "TS_PIN",
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	}, {
		.indexed = 1,
		.type = IIO_TEMP,
		.channel = 1,
		.address = AXP288_PMIC_ADC_H,
		.datasheet_name = "PMIC_TEMP",
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	}, {
		.indexed = 1,
		.type = IIO_TEMP,
		.channel = 2,
		.address = AXP288_GP_ADC_H,
		.datasheet_name = "GPADC",
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	}, {
		.indexed = 1,
		.type = IIO_CURRENT,
		.channel = 3,
		.address = AXP20X_BATT_CHRG_I_H,
		.datasheet_name = "BATT_CHG_I",
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	}, {
		.indexed = 1,
		.type = IIO_CURRENT,
		.channel = 4,
		.address = AXP20X_BATT_DISCHRG_I_H,
		.datasheet_name = "BATT_DISCHRG_I",
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	}, {
		.indexed = 1,
		.type = IIO_VOLTAGE,
		.channel = 5,
		.address = AXP20X_BATT_V_H,
		.datasheet_name = "BATT_V",
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	},
};

#define AXP288_ADC_MAP(_adc_channel_label, _consumer_dev_name,	\
		_consumer_channel)				\
	{							\
		.adc_channel_label = _adc_channel_label,	\
		.consumer_dev_name = _consumer_dev_name,	\
		.consumer_channel = _consumer_channel,		\
	}

/* for consumer drivers */
static struct iio_map axp288_adc_default_maps[] = {
	AXP288_ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
	AXP288_ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
	AXP288_ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
	AXP288_ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
	AXP288_ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
	AXP288_ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
	{},
};

static int axp288_adc_read_channel(int *val, unsigned long address,
				struct regmap *regmap)
{
	u8 buf[2];

	if (regmap_bulk_read(regmap, address, buf, 2))
		return -EIO;
	*val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F);

	return IIO_VAL_INT;
}

static int axp288_adc_set_ts(struct regmap *regmap, unsigned int mode,
				unsigned long address)
{
	/* channels other than GPADC do not need to switch TS pin */
	if (address != AXP288_GP_ADC_H)
		return 0;

	return regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, mode);
}

static int axp288_adc_read_raw(struct iio_dev *indio_dev,
			struct iio_chan_spec const *chan,
			int *val, int *val2, long mask)
{
	int ret;
	struct axp288_adc_info *info = iio_priv(indio_dev);

	mutex_lock(&indio_dev->mlock);
	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_GPADC,
					chan->address)) {
			dev_err(&indio_dev->dev, "GPADC mode\n");
			ret = -EINVAL;
			break;
		}
		ret = axp288_adc_read_channel(val, chan->address, info->regmap);
		if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_ON,
						chan->address))
			dev_err(&indio_dev->dev, "TS pin restore\n");
		break;
	default:
		ret = -EINVAL;
	}
	mutex_unlock(&indio_dev->mlock);

	return ret;
}

static int axp288_adc_set_state(struct regmap *regmap)
{
	/* ADC should be always enabled for internal FG to function */
	if (regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, AXP288_ADC_TS_PIN_ON))
		return -EIO;

	return regmap_write(regmap, AXP20X_ADC_EN1, AXP288_ADC_EN_MASK);
}

static const struct iio_info axp288_adc_iio_info = {
	.read_raw = &axp288_adc_read_raw,
	.driver_module = THIS_MODULE,
};

static int axp288_adc_probe(struct platform_device *pdev)
{
	int ret;
	struct axp288_adc_info *info;
	struct iio_dev *indio_dev;
	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);

	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
	if (!indio_dev)
		return -ENOMEM;

	info = iio_priv(indio_dev);
	info->irq = platform_get_irq(pdev, 0);
	if (info->irq < 0) {
		dev_err(&pdev->dev, "no irq resource?\n");
		return info->irq;
	}
	platform_set_drvdata(pdev, indio_dev);
	info->regmap = axp20x->regmap;
	/*
	 * Set ADC to enabled state at all time, including system suspend.
	 * otherwise internal fuel gauge functionality may be affected.
	 */
	ret = axp288_adc_set_state(axp20x->regmap);
	if (ret) {
		dev_err(&pdev->dev, "unable to enable ADC device\n");
		return ret;
	}

	indio_dev->dev.parent = &pdev->dev;
	indio_dev->name = pdev->name;
	indio_dev->channels = axp288_adc_channels;
	indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels);
	indio_dev->info = &axp288_adc_iio_info;
	indio_dev->modes = INDIO_DIRECT_MODE;
	ret = iio_map_array_register(indio_dev, axp288_adc_default_maps);
	if (ret < 0)
		return ret;

	ret = iio_device_register(indio_dev);
	if (ret < 0) {
		dev_err(&pdev->dev, "unable to register iio device\n");
		goto err_array_unregister;
	}
	return 0;

err_array_unregister:
	iio_map_array_unregister(indio_dev);

	return ret;
}

static int axp288_adc_remove(struct platform_device *pdev)
{
	struct iio_dev *indio_dev = platform_get_drvdata(pdev);

	iio_device_unregister(indio_dev);
	iio_map_array_unregister(indio_dev);

	return 0;
}

static const struct platform_device_id axp288_adc_id_table[] = {
	{ .name = "axp288_adc" },
	{},
};

static struct platform_driver axp288_adc_driver = {
	.probe = axp288_adc_probe,
	.remove = axp288_adc_remove,
	.id_table = axp288_adc_id_table,
	.driver = {
		.name = "axp288_adc",
	},
};

MODULE_DEVICE_TABLE(platform, axp288_adc_id_table);

module_platform_driver(axp288_adc_driver);

MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@linux.intel.com>");
MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver");
MODULE_LICENSE("GPL");