1
2
3
4
5
6
7
8
9
10#include <linux/delay.h>
11#include <linux/iio/iio.h>
12#include <linux/iio/driver.h>
13#include <linux/iio/machine.h>
14#include <linux/mfd/lp8788.h>
15#include <linux/module.h>
16#include <linux/mutex.h>
17#include <linux/platform_device.h>
18#include <linux/slab.h>
19
20
21#define LP8788_ADC_CONF 0x60
22#define LP8788_ADC_RAW 0x61
23#define LP8788_ADC_DONE 0x63
24
25#define ADC_CONV_START 1
26
27struct lp8788_adc {
28 struct lp8788 *lp;
29 struct iio_map *map;
30 struct mutex lock;
31};
32
33static const int lp8788_scale[LPADC_MAX] = {
34 [LPADC_VBATT_5P5] = 1343101,
35 [LPADC_VIN_CHG] = 3052503,
36 [LPADC_IBATT] = 610500,
37 [LPADC_IC_TEMP] = 61050,
38 [LPADC_VBATT_6P0] = 1465201,
39 [LPADC_VBATT_5P0] = 1221001,
40 [LPADC_ADC1] = 610500,
41 [LPADC_ADC2] = 610500,
42 [LPADC_VDD] = 1025641,
43 [LPADC_VCOIN] = 757020,
44 [LPADC_ADC3] = 610500,
45 [LPADC_ADC4] = 610500,
46};
47
48static int lp8788_get_adc_result(struct lp8788_adc *adc, enum lp8788_adc_id id,
49 int *val)
50{
51 unsigned int msb;
52 unsigned int lsb;
53 unsigned int result;
54 u8 data;
55 u8 rawdata[2];
56 int size = ARRAY_SIZE(rawdata);
57 int retry = 5;
58 int ret;
59
60 data = (id << 1) | ADC_CONV_START;
61 ret = lp8788_write_byte(adc->lp, LP8788_ADC_CONF, data);
62 if (ret)
63 goto err_io;
64
65
66 data = 0;
67 while (retry--) {
68 usleep_range(100, 200);
69
70 ret = lp8788_read_byte(adc->lp, LP8788_ADC_DONE, &data);
71 if (ret)
72 goto err_io;
73
74
75 if (data)
76 break;
77 }
78
79 ret = lp8788_read_multi_bytes(adc->lp, LP8788_ADC_RAW, rawdata, size);
80 if (ret)
81 goto err_io;
82
83 msb = (rawdata[0] << 4) & 0x00000ff0;
84 lsb = (rawdata[1] >> 4) & 0x0000000f;
85 result = msb | lsb;
86 *val = result;
87
88 return 0;
89
90err_io:
91 return ret;
92}
93
94static int lp8788_adc_read_raw(struct iio_dev *indio_dev,
95 struct iio_chan_spec const *chan,
96 int *val, int *val2, long mask)
97{
98 struct lp8788_adc *adc = iio_priv(indio_dev);
99 enum lp8788_adc_id id = chan->channel;
100 int ret;
101
102 mutex_lock(&adc->lock);
103
104 switch (mask) {
105 case IIO_CHAN_INFO_RAW:
106 ret = lp8788_get_adc_result(adc, id, val) ? -EIO : IIO_VAL_INT;
107 break;
108 case IIO_CHAN_INFO_SCALE:
109 *val = lp8788_scale[id] / 1000000;
110 *val2 = lp8788_scale[id] % 1000000;
111 ret = IIO_VAL_INT_PLUS_MICRO;
112 break;
113 default:
114 ret = -EINVAL;
115 break;
116 }
117
118 mutex_unlock(&adc->lock);
119
120 return ret;
121}
122
123static const struct iio_info lp8788_adc_info = {
124 .read_raw = &lp8788_adc_read_raw,
125};
126
127#define LP8788_CHAN(_id, _type) { \
128 .type = _type, \
129 .indexed = 1, \
130 .channel = LPADC_##_id, \
131 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
132 BIT(IIO_CHAN_INFO_SCALE), \
133 .datasheet_name = #_id, \
134}
135
136static const struct iio_chan_spec lp8788_adc_channels[] = {
137 [LPADC_VBATT_5P5] = LP8788_CHAN(VBATT_5P5, IIO_VOLTAGE),
138 [LPADC_VIN_CHG] = LP8788_CHAN(VIN_CHG, IIO_VOLTAGE),
139 [LPADC_IBATT] = LP8788_CHAN(IBATT, IIO_CURRENT),
140 [LPADC_IC_TEMP] = LP8788_CHAN(IC_TEMP, IIO_TEMP),
141 [LPADC_VBATT_6P0] = LP8788_CHAN(VBATT_6P0, IIO_VOLTAGE),
142 [LPADC_VBATT_5P0] = LP8788_CHAN(VBATT_5P0, IIO_VOLTAGE),
143 [LPADC_ADC1] = LP8788_CHAN(ADC1, IIO_VOLTAGE),
144 [LPADC_ADC2] = LP8788_CHAN(ADC2, IIO_VOLTAGE),
145 [LPADC_VDD] = LP8788_CHAN(VDD, IIO_VOLTAGE),
146 [LPADC_VCOIN] = LP8788_CHAN(VCOIN, IIO_VOLTAGE),
147 [LPADC_ADC3] = LP8788_CHAN(ADC3, IIO_VOLTAGE),
148 [LPADC_ADC4] = LP8788_CHAN(ADC4, IIO_VOLTAGE),
149};
150
151
152static struct iio_map lp8788_default_iio_maps[] = {
153 {
154 .consumer_dev_name = "lp8788-charger",
155 .consumer_channel = "lp8788_vbatt_5p0",
156 .adc_channel_label = "VBATT_5P0",
157 },
158 {
159 .consumer_dev_name = "lp8788-charger",
160 .consumer_channel = "lp8788_adc1",
161 .adc_channel_label = "ADC1",
162 },
163 { }
164};
165
166static int lp8788_iio_map_register(struct iio_dev *indio_dev,
167 struct lp8788_platform_data *pdata,
168 struct lp8788_adc *adc)
169{
170 struct iio_map *map;
171 int ret;
172
173 map = (!pdata || !pdata->adc_pdata) ?
174 lp8788_default_iio_maps : pdata->adc_pdata;
175
176 ret = iio_map_array_register(indio_dev, map);
177 if (ret) {
178 dev_err(&indio_dev->dev, "iio map err: %d\n", ret);
179 return ret;
180 }
181
182 adc->map = map;
183 return 0;
184}
185
186static int lp8788_adc_probe(struct platform_device *pdev)
187{
188 struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
189 struct iio_dev *indio_dev;
190 struct lp8788_adc *adc;
191 int ret;
192
193 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
194 if (!indio_dev)
195 return -ENOMEM;
196
197 adc = iio_priv(indio_dev);
198 adc->lp = lp;
199 platform_set_drvdata(pdev, indio_dev);
200
201 ret = lp8788_iio_map_register(indio_dev, lp->pdata, adc);
202 if (ret)
203 return ret;
204
205 mutex_init(&adc->lock);
206
207 indio_dev->name = pdev->name;
208 indio_dev->modes = INDIO_DIRECT_MODE;
209 indio_dev->info = &lp8788_adc_info;
210 indio_dev->channels = lp8788_adc_channels;
211 indio_dev->num_channels = ARRAY_SIZE(lp8788_adc_channels);
212
213 ret = iio_device_register(indio_dev);
214 if (ret) {
215 dev_err(&pdev->dev, "iio dev register err: %d\n", ret);
216 goto err_iio_device;
217 }
218
219 return 0;
220
221err_iio_device:
222 iio_map_array_unregister(indio_dev);
223 return ret;
224}
225
226static int lp8788_adc_remove(struct platform_device *pdev)
227{
228 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
229
230 iio_device_unregister(indio_dev);
231 iio_map_array_unregister(indio_dev);
232
233 return 0;
234}
235
236static struct platform_driver lp8788_adc_driver = {
237 .probe = lp8788_adc_probe,
238 .remove = lp8788_adc_remove,
239 .driver = {
240 .name = LP8788_DEV_ADC,
241 },
242};
243module_platform_driver(lp8788_adc_driver);
244
245MODULE_DESCRIPTION("Texas Instruments LP8788 ADC Driver");
246MODULE_AUTHOR("Milo Kim");
247MODULE_LICENSE("GPL");
248MODULE_ALIAS("platform:lp8788-adc");
249
