1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2022 Richtek Technology Corp.
4 *
5 * Author: ChiaEn Wu <chiaen_wu@richtek.com>
6 */
7
8#include <linux/bits.h>
9#include <linux/bitfield.h>
10#include <linux/iio/iio.h>
11#include <linux/kernel.h>
12#include <linux/mod_devicetable.h>
13#include <linux/module.h>
14#include <linux/mutex.h>
15#include <linux/platform_device.h>
16#include <linux/regmap.h>
17#include <linux/sysfs.h>
18#include <linux/units.h>
19
20#include <dt-bindings/iio/adc/mediatek,mt6370_adc.h>
21
22#define MT6370_REG_DEV_INFO 0x100
23#define MT6370_REG_CHG_CTRL3 0x113
24#define MT6370_REG_CHG_CTRL7 0x117
25#define MT6370_REG_CHG_ADC 0x121
26#define MT6370_REG_ADC_DATA_H 0x14C
27
28#define MT6370_ADC_START_MASK BIT(0)
29#define MT6370_ADC_IN_SEL_MASK GENMASK(7, 4)
30#define MT6370_AICR_ICHG_MASK GENMASK(7, 2)
31#define MT6370_VENID_MASK GENMASK(7, 4)
32
33#define MT6370_AICR_100_mA 0x0
34#define MT6370_AICR_150_mA 0x1
35#define MT6370_AICR_200_mA 0x2
36#define MT6370_AICR_250_mA 0x3
37#define MT6370_AICR_300_mA 0x4
38#define MT6370_AICR_350_mA 0x5
39
40#define MT6370_ICHG_100_mA 0x0
41#define MT6370_ICHG_200_mA 0x1
42#define MT6370_ICHG_300_mA 0x2
43#define MT6370_ICHG_400_mA 0x3
44#define MT6370_ICHG_500_mA 0x4
45#define MT6370_ICHG_600_mA 0x5
46#define MT6370_ICHG_700_mA 0x6
47#define MT6370_ICHG_800_mA 0x7
48
49#define ADC_CONV_TIME_MS 35
50#define ADC_CONV_POLLING_TIME_US 1000
51
52#define MT6370_VID_RT5081 0x8
53#define MT6370_VID_RT5081A 0xA
54#define MT6370_VID_MT6370 0xE
55
56struct mt6370_adc_data {
57 struct device *dev;
58 struct regmap *regmap;
59 /*
60 * This mutex lock is for preventing the different ADC channels
61 * from being read at the same time.
62 */
63 struct mutex adc_lock;
64 unsigned int vid;
65};
66
67static int mt6370_adc_read_channel(struct mt6370_adc_data *priv, int chan,
68 unsigned long addr, int *val)
69{
70 unsigned int reg_val;
71 __be16 be_val;
72 int ret;
73
74 mutex_lock(&priv->adc_lock);
75
76 reg_val = MT6370_ADC_START_MASK |
77 FIELD_PREP(MT6370_ADC_IN_SEL_MASK, addr);
78 ret = regmap_write(map: priv->regmap, MT6370_REG_CHG_ADC, val: reg_val);
79 if (ret)
80 goto adc_unlock;
81
82 msleep(ADC_CONV_TIME_MS);
83
84 ret = regmap_read_poll_timeout(priv->regmap,
85 MT6370_REG_CHG_ADC, reg_val,
86 !(reg_val & MT6370_ADC_START_MASK),
87 ADC_CONV_POLLING_TIME_US,
88 ADC_CONV_TIME_MS * MILLI * 3);
89 if (ret) {
90 dev_err(priv->dev, "Failed to read ADC register (%d)\n", ret);
91 goto adc_unlock;
92 }
93
94 ret = regmap_raw_read(map: priv->regmap, MT6370_REG_ADC_DATA_H,
95 val: &be_val, val_len: sizeof(be_val));
96 if (ret)
97 goto adc_unlock;
98
99 *val = be16_to_cpu(be_val);
100 ret = IIO_VAL_INT;
101
102adc_unlock:
103 mutex_unlock(lock: &priv->adc_lock);
104
105 return ret;
106}
107
108static int mt6370_adc_get_ibus_scale(struct mt6370_adc_data *priv)
109{
110 switch (priv->vid) {
111 case MT6370_VID_RT5081:
112 case MT6370_VID_RT5081A:
113 case MT6370_VID_MT6370:
114 return 3350;
115 default:
116 return 3875;
117 }
118}
119
120static int mt6370_adc_get_ibat_scale(struct mt6370_adc_data *priv)
121{
122 switch (priv->vid) {
123 case MT6370_VID_RT5081:
124 case MT6370_VID_RT5081A:
125 case MT6370_VID_MT6370:
126 return 2680;
127 default:
128 return 3870;
129 }
130}
131
132static int mt6370_adc_read_scale(struct mt6370_adc_data *priv,
133 int chan, int *val1, int *val2)
134{
135 unsigned int reg_val;
136 int ret;
137
138 switch (chan) {
139 case MT6370_CHAN_VBAT:
140 case MT6370_CHAN_VSYS:
141 case MT6370_CHAN_CHG_VDDP:
142 *val1 = 5;
143 return IIO_VAL_INT;
144 case MT6370_CHAN_IBUS:
145 ret = regmap_read(map: priv->regmap, MT6370_REG_CHG_CTRL3, val: &reg_val);
146 if (ret)
147 return ret;
148
149 reg_val = FIELD_GET(MT6370_AICR_ICHG_MASK, reg_val);
150 switch (reg_val) {
151 case MT6370_AICR_100_mA:
152 case MT6370_AICR_150_mA:
153 case MT6370_AICR_200_mA:
154 case MT6370_AICR_250_mA:
155 case MT6370_AICR_300_mA:
156 case MT6370_AICR_350_mA:
157 *val1 = mt6370_adc_get_ibus_scale(priv);
158 break;
159 default:
160 *val1 = 5000;
161 break;
162 }
163
164 *val2 = 100;
165
166 return IIO_VAL_FRACTIONAL;
167 case MT6370_CHAN_IBAT:
168 ret = regmap_read(map: priv->regmap, MT6370_REG_CHG_CTRL7, val: &reg_val);
169 if (ret)
170 return ret;
171
172 reg_val = FIELD_GET(MT6370_AICR_ICHG_MASK, reg_val);
173 switch (reg_val) {
174 case MT6370_ICHG_100_mA:
175 case MT6370_ICHG_200_mA:
176 case MT6370_ICHG_300_mA:
177 case MT6370_ICHG_400_mA:
178 *val1 = 2375;
179 break;
180 case MT6370_ICHG_500_mA:
181 case MT6370_ICHG_600_mA:
182 case MT6370_ICHG_700_mA:
183 case MT6370_ICHG_800_mA:
184 *val1 = mt6370_adc_get_ibat_scale(priv);
185 break;
186 default:
187 *val1 = 5000;
188 break;
189 }
190
191 *val2 = 100;
192
193 return IIO_VAL_FRACTIONAL;
194 case MT6370_CHAN_VBUSDIV5:
195 *val1 = 25;
196 return IIO_VAL_INT;
197 case MT6370_CHAN_VBUSDIV2:
198 *val1 = 10;
199 return IIO_VAL_INT;
200 case MT6370_CHAN_TS_BAT:
201 *val1 = 25;
202 *val2 = 10000;
203 return IIO_VAL_FRACTIONAL;
204 case MT6370_CHAN_TEMP_JC:
205 *val1 = 2000;
206 return IIO_VAL_INT;
207 default:
208 return -EINVAL;
209 }
210}
211
212static int mt6370_adc_read_offset(struct mt6370_adc_data *priv,
213 int chan, int *val)
214{
215 *val = -20;
216
217 return IIO_VAL_INT;
218}
219
220static int mt6370_adc_read_raw(struct iio_dev *iio_dev,
221 const struct iio_chan_spec *chan,
222 int *val, int *val2, long mask)
223{
224 struct mt6370_adc_data *priv = iio_priv(indio_dev: iio_dev);
225
226 switch (mask) {
227 case IIO_CHAN_INFO_RAW:
228 return mt6370_adc_read_channel(priv, chan: chan->channel,
229 addr: chan->address, val);
230 case IIO_CHAN_INFO_SCALE:
231 return mt6370_adc_read_scale(priv, chan: chan->channel, val1: val, val2);
232 case IIO_CHAN_INFO_OFFSET:
233 return mt6370_adc_read_offset(priv, chan: chan->channel, val);
234 default:
235 return -EINVAL;
236 }
237}
238
239static const char * const mt6370_channel_labels[MT6370_CHAN_MAX] = {
240 [MT6370_CHAN_VBUSDIV5] = "vbusdiv5",
241 [MT6370_CHAN_VBUSDIV2] = "vbusdiv2",
242 [MT6370_CHAN_VSYS] = "vsys",
243 [MT6370_CHAN_VBAT] = "vbat",
244 [MT6370_CHAN_TS_BAT] = "ts_bat",
245 [MT6370_CHAN_IBUS] = "ibus",
246 [MT6370_CHAN_IBAT] = "ibat",
247 [MT6370_CHAN_CHG_VDDP] = "chg_vddp",
248 [MT6370_CHAN_TEMP_JC] = "temp_jc",
249};
250
251static int mt6370_adc_read_label(struct iio_dev *iio_dev,
252 struct iio_chan_spec const *chan, char *label)
253{
254 return sysfs_emit(buf: label, fmt: "%s\n", mt6370_channel_labels[chan->channel]);
255}
256
257static const struct iio_info mt6370_adc_iio_info = {
258 .read_raw = mt6370_adc_read_raw,
259 .read_label = mt6370_adc_read_label,
260};
261
262#define MT6370_ADC_CHAN(_idx, _type, _addr, _extra_info) { \
263 .type = _type, \
264 .channel = MT6370_CHAN_##_idx, \
265 .address = _addr, \
266 .scan_index = MT6370_CHAN_##_idx, \
267 .indexed = 1, \
268 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
269 BIT(IIO_CHAN_INFO_SCALE) | \
270 _extra_info, \
271}
272
273static const struct iio_chan_spec mt6370_adc_channels[] = {
274 MT6370_ADC_CHAN(VBUSDIV5, IIO_VOLTAGE, 1, 0),
275 MT6370_ADC_CHAN(VBUSDIV2, IIO_VOLTAGE, 2, 0),
276 MT6370_ADC_CHAN(VSYS, IIO_VOLTAGE, 3, 0),
277 MT6370_ADC_CHAN(VBAT, IIO_VOLTAGE, 4, 0),
278 MT6370_ADC_CHAN(TS_BAT, IIO_VOLTAGE, 6, 0),
279 MT6370_ADC_CHAN(IBUS, IIO_CURRENT, 8, 0),
280 MT6370_ADC_CHAN(IBAT, IIO_CURRENT, 9, 0),
281 MT6370_ADC_CHAN(CHG_VDDP, IIO_VOLTAGE, 11, 0),
282 MT6370_ADC_CHAN(TEMP_JC, IIO_TEMP, 12, BIT(IIO_CHAN_INFO_OFFSET)),
283};
284
285static int mt6370_get_vendor_info(struct mt6370_adc_data *priv)
286{
287 unsigned int dev_info;
288 int ret;
289
290 ret = regmap_read(map: priv->regmap, MT6370_REG_DEV_INFO, val: &dev_info);
291 if (ret)
292 return ret;
293
294 priv->vid = FIELD_GET(MT6370_VENID_MASK, dev_info);
295
296 return 0;
297}
298
299static int mt6370_adc_probe(struct platform_device *pdev)
300{
301 struct device *dev = &pdev->dev;
302 struct mt6370_adc_data *priv;
303 struct iio_dev *indio_dev;
304 struct regmap *regmap;
305 int ret;
306
307 regmap = dev_get_regmap(dev: pdev->dev.parent, NULL);
308 if (!regmap)
309 return dev_err_probe(dev, err: -ENODEV, fmt: "Failed to get regmap\n");
310
311 indio_dev = devm_iio_device_alloc(parent: dev, sizeof_priv: sizeof(*priv));
312 if (!indio_dev)
313 return -ENOMEM;
314
315 priv = iio_priv(indio_dev);
316 priv->dev = dev;
317 priv->regmap = regmap;
318 mutex_init(&priv->adc_lock);
319
320 ret = mt6370_get_vendor_info(priv);
321 if (ret)
322 return dev_err_probe(dev, err: ret, fmt: "Failed to get vid\n");
323
324 ret = regmap_write(map: priv->regmap, MT6370_REG_CHG_ADC, val: 0);
325 if (ret)
326 return dev_err_probe(dev, err: ret, fmt: "Failed to reset ADC\n");
327
328 indio_dev->name = "mt6370-adc";
329 indio_dev->info = &mt6370_adc_iio_info;
330 indio_dev->modes = INDIO_DIRECT_MODE;
331 indio_dev->channels = mt6370_adc_channels;
332 indio_dev->num_channels = ARRAY_SIZE(mt6370_adc_channels);
333
334 return devm_iio_device_register(dev, indio_dev);
335}
336
337static const struct of_device_id mt6370_adc_of_id[] = {
338 { .compatible = "mediatek,mt6370-adc", },
339 { }
340};
341MODULE_DEVICE_TABLE(of, mt6370_adc_of_id);
342
343static struct platform_driver mt6370_adc_driver = {
344 .driver = {
345 .name = "mt6370-adc",
346 .of_match_table = mt6370_adc_of_id,
347 },
348 .probe = mt6370_adc_probe,
349};
350module_platform_driver(mt6370_adc_driver);
351
352MODULE_AUTHOR("ChiaEn Wu <chiaen_wu@richtek.com>");
353MODULE_DESCRIPTION("MT6370 ADC Driver");
354MODULE_LICENSE("GPL v2");
355

source code of linux/drivers/iio/adc/mt6370-adc.c