2 * axp288_adc.c - X-Powers AXP288 PMIC ADC Driver
4 * Copyright (C) 2014 Intel Corporation
6 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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>
26 #include <linux/iio/iio.h>
27 #include <linux/iio/machine.h>
28 #include <linux/iio/driver.h>
30 #define AXP288_ADC_EN_MASK 0xF1
31 #define AXP288_ADC_TS_PIN_GPADC 0xF2
32 #define AXP288_ADC_TS_PIN_ON 0xF3
38 AXP288_ADC_BATT_CHRG_I,
39 AXP288_ADC_BATT_DISCHRG_I,
44 struct axp288_adc_info {
46 struct regmap *regmap;
49 static const struct iio_chan_spec axp288_adc_channels[] = {
54 .address = AXP288_TS_ADC_H,
55 .datasheet_name = "TS_PIN",
56 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
61 .address = AXP288_PMIC_ADC_H,
62 .datasheet_name = "PMIC_TEMP",
63 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
68 .address = AXP288_GP_ADC_H,
69 .datasheet_name = "GPADC",
70 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
75 .address = AXP20X_BATT_CHRG_I_H,
76 .datasheet_name = "BATT_CHG_I",
77 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
82 .address = AXP20X_BATT_DISCHRG_I_H,
83 .datasheet_name = "BATT_DISCHRG_I",
84 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
89 .address = AXP20X_BATT_V_H,
90 .datasheet_name = "BATT_V",
91 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
95 #define AXP288_ADC_MAP(_adc_channel_label, _consumer_dev_name, \
98 .adc_channel_label = _adc_channel_label, \
99 .consumer_dev_name = _consumer_dev_name, \
100 .consumer_channel = _consumer_channel, \
103 /* for consumer drivers */
104 static struct iio_map axp288_adc_default_maps[] = {
105 AXP288_ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
106 AXP288_ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
107 AXP288_ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
108 AXP288_ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
109 AXP288_ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
110 AXP288_ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
114 static int axp288_adc_read_channel(int *val, unsigned long address,
115 struct regmap *regmap)
119 if (regmap_bulk_read(regmap, address, buf, 2))
121 *val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F);
126 static int axp288_adc_set_ts(struct regmap *regmap, unsigned int mode,
127 unsigned long address)
131 /* channels other than GPADC do not need to switch TS pin */
132 if (address != AXP288_GP_ADC_H)
135 ret = regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, mode);
139 /* When switching to the GPADC pin give things some time to settle */
140 if (mode == AXP288_ADC_TS_PIN_GPADC)
141 usleep_range(6000, 10000);
146 static int axp288_adc_read_raw(struct iio_dev *indio_dev,
147 struct iio_chan_spec const *chan,
148 int *val, int *val2, long mask)
151 struct axp288_adc_info *info = iio_priv(indio_dev);
153 mutex_lock(&indio_dev->mlock);
155 case IIO_CHAN_INFO_RAW:
156 if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_GPADC,
158 dev_err(&indio_dev->dev, "GPADC mode\n");
162 ret = axp288_adc_read_channel(val, chan->address, info->regmap);
163 if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_ON,
165 dev_err(&indio_dev->dev, "TS pin restore\n");
170 mutex_unlock(&indio_dev->mlock);
175 static int axp288_adc_set_state(struct regmap *regmap)
177 /* ADC should be always enabled for internal FG to function */
178 if (regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, AXP288_ADC_TS_PIN_ON))
181 return regmap_write(regmap, AXP20X_ADC_EN1, AXP288_ADC_EN_MASK);
184 static const struct iio_info axp288_adc_iio_info = {
185 .read_raw = &axp288_adc_read_raw,
186 .driver_module = THIS_MODULE,
189 static int axp288_adc_probe(struct platform_device *pdev)
192 struct axp288_adc_info *info;
193 struct iio_dev *indio_dev;
194 struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
196 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
200 info = iio_priv(indio_dev);
201 info->irq = platform_get_irq(pdev, 0);
203 dev_err(&pdev->dev, "no irq resource?\n");
206 platform_set_drvdata(pdev, indio_dev);
207 info->regmap = axp20x->regmap;
209 * Set ADC to enabled state at all time, including system suspend.
210 * otherwise internal fuel gauge functionality may be affected.
212 ret = axp288_adc_set_state(axp20x->regmap);
214 dev_err(&pdev->dev, "unable to enable ADC device\n");
218 indio_dev->dev.parent = &pdev->dev;
219 indio_dev->name = pdev->name;
220 indio_dev->channels = axp288_adc_channels;
221 indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels);
222 indio_dev->info = &axp288_adc_iio_info;
223 indio_dev->modes = INDIO_DIRECT_MODE;
224 ret = iio_map_array_register(indio_dev, axp288_adc_default_maps);
228 ret = iio_device_register(indio_dev);
230 dev_err(&pdev->dev, "unable to register iio device\n");
231 goto err_array_unregister;
235 err_array_unregister:
236 iio_map_array_unregister(indio_dev);
241 static int axp288_adc_remove(struct platform_device *pdev)
243 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
245 iio_device_unregister(indio_dev);
246 iio_map_array_unregister(indio_dev);
251 static const struct platform_device_id axp288_adc_id_table[] = {
252 { .name = "axp288_adc" },
256 static struct platform_driver axp288_adc_driver = {
257 .probe = axp288_adc_probe,
258 .remove = axp288_adc_remove,
259 .id_table = axp288_adc_id_table,
261 .name = "axp288_adc",
265 MODULE_DEVICE_TABLE(platform, axp288_adc_id_table);
267 module_platform_driver(axp288_adc_driver);
269 MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@linux.intel.com>");
270 MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver");
271 MODULE_LICENSE("GPL");