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13#include <linux/delay.h>
14#include <linux/iio/iio.h>
15#include <linux/iio/driver.h>
16#include <linux/iio/machine.h>
17#include <linux/mfd/lp8788.h>
18#include <linux/module.h>
19#include <linux/mutex.h>
20#include <linux/platform_device.h>
21#include <linux/slab.h>
22
23
24#define LP8788_ADC_CONF 0x60
25#define LP8788_ADC_RAW 0x61
26#define LP8788_ADC_DONE 0x63
27
28#define ADC_CONV_START 1
29
30struct lp8788_adc {
31 struct lp8788 *lp;
32 struct iio_map *map;
33 struct mutex lock;
34};
35
36static const int lp8788_scale[LPADC_MAX] = {
37 [LPADC_VBATT_5P5] = 1343101,
38 [LPADC_VIN_CHG] = 3052503,
39 [LPADC_IBATT] = 610500,
40 [LPADC_IC_TEMP] = 61050,
41 [LPADC_VBATT_6P0] = 1465201,
42 [LPADC_VBATT_5P0] = 1221001,
43 [LPADC_ADC1] = 610500,
44 [LPADC_ADC2] = 610500,
45 [LPADC_VDD] = 1025641,
46 [LPADC_VCOIN] = 757020,
47 [LPADC_ADC3] = 610500,
48 [LPADC_ADC4] = 610500,
49};
50
51static int lp8788_get_adc_result(struct lp8788_adc *adc, enum lp8788_adc_id id,
52 int *val)
53{
54 unsigned int msb;
55 unsigned int lsb;
56 unsigned int result;
57 u8 data;
58 u8 rawdata[2];
59 int size = ARRAY_SIZE(rawdata);
60 int retry = 5;
61 int ret;
62
63 data = (id << 1) | ADC_CONV_START;
64 ret = lp8788_write_byte(adc->lp, LP8788_ADC_CONF, data);
65 if (ret)
66 goto err_io;
67
68
69 data = 0;
70 while (retry--) {
71 usleep_range(100, 200);
72
73 ret = lp8788_read_byte(adc->lp, LP8788_ADC_DONE, &data);
74 if (ret)
75 goto err_io;
76
77
78 if (data)
79 break;
80 }
81
82 ret = lp8788_read_multi_bytes(adc->lp, LP8788_ADC_RAW, rawdata, size);
83 if (ret)
84 goto err_io;
85
86 msb = (rawdata[0] << 4) & 0x00000ff0;
87 lsb = (rawdata[1] >> 4) & 0x0000000f;
88 result = msb | lsb;
89 *val = result;
90
91 return 0;
92
93err_io:
94 return ret;
95}
96
97static int lp8788_adc_read_raw(struct iio_dev *indio_dev,
98 struct iio_chan_spec const *chan,
99 int *val, int *val2, long mask)
100{
101 struct lp8788_adc *adc = iio_priv(indio_dev);
102 enum lp8788_adc_id id = chan->channel;
103 int ret;
104
105 mutex_lock(&adc->lock);
106
107 switch (mask) {
108 case IIO_CHAN_INFO_RAW:
109 ret = lp8788_get_adc_result(adc, id, val) ? -EIO : IIO_VAL_INT;
110 break;
111 case IIO_CHAN_INFO_SCALE:
112 *val = lp8788_scale[id] / 1000000;
113 *val2 = lp8788_scale[id] % 1000000;
114 ret = IIO_VAL_INT_PLUS_MICRO;
115 break;
116 default:
117 ret = -EINVAL;
118 break;
119 }
120
121 mutex_unlock(&adc->lock);
122
123 return ret;
124}
125
126static const struct iio_info lp8788_adc_info = {
127 .read_raw = &lp8788_adc_read_raw,
128 .driver_module = THIS_MODULE,
129};
130
131#define LP8788_CHAN(_id, _type) { \
132 .type = _type, \
133 .indexed = 1, \
134 .channel = LPADC_##_id, \
135 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
136 BIT(IIO_CHAN_INFO_SCALE), \
137 .datasheet_name = #_id, \
138}
139
140static const struct iio_chan_spec lp8788_adc_channels[] = {
141 [LPADC_VBATT_5P5] = LP8788_CHAN(VBATT_5P5, IIO_VOLTAGE),
142 [LPADC_VIN_CHG] = LP8788_CHAN(VIN_CHG, IIO_VOLTAGE),
143 [LPADC_IBATT] = LP8788_CHAN(IBATT, IIO_CURRENT),
144 [LPADC_IC_TEMP] = LP8788_CHAN(IC_TEMP, IIO_TEMP),
145 [LPADC_VBATT_6P0] = LP8788_CHAN(VBATT_6P0, IIO_VOLTAGE),
146 [LPADC_VBATT_5P0] = LP8788_CHAN(VBATT_5P0, IIO_VOLTAGE),
147 [LPADC_ADC1] = LP8788_CHAN(ADC1, IIO_VOLTAGE),
148 [LPADC_ADC2] = LP8788_CHAN(ADC2, IIO_VOLTAGE),
149 [LPADC_VDD] = LP8788_CHAN(VDD, IIO_VOLTAGE),
150 [LPADC_VCOIN] = LP8788_CHAN(VCOIN, IIO_VOLTAGE),
151 [LPADC_ADC3] = LP8788_CHAN(ADC3, IIO_VOLTAGE),
152 [LPADC_ADC4] = LP8788_CHAN(ADC4, IIO_VOLTAGE),
153};
154
155
156static struct iio_map lp8788_default_iio_maps[] = {
157 {
158 .consumer_dev_name = "lp8788-charger",
159 .consumer_channel = "lp8788_vbatt_5p0",
160 .adc_channel_label = "VBATT_5P0",
161 },
162 {
163 .consumer_dev_name = "lp8788-charger",
164 .consumer_channel = "lp8788_adc1",
165 .adc_channel_label = "ADC1",
166 },
167 { }
168};
169
170static int lp8788_iio_map_register(struct iio_dev *indio_dev,
171 struct lp8788_platform_data *pdata,
172 struct lp8788_adc *adc)
173{
174 struct iio_map *map;
175 int ret;
176
177 map = (!pdata || !pdata->adc_pdata) ?
178 lp8788_default_iio_maps : pdata->adc_pdata;
179
180 ret = iio_map_array_register(indio_dev, map);
181 if (ret) {
182 dev_err(&indio_dev->dev, "iio map err: %d\n", ret);
183 return ret;
184 }
185
186 adc->map = map;
187 return 0;
188}
189
190static int lp8788_adc_probe(struct platform_device *pdev)
191{
192 struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
193 struct iio_dev *indio_dev;
194 struct lp8788_adc *adc;
195 int ret;
196
197 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
198 if (!indio_dev)
199 return -ENOMEM;
200
201 adc = iio_priv(indio_dev);
202 adc->lp = lp;
203 platform_set_drvdata(pdev, indio_dev);
204
205 indio_dev->dev.of_node = pdev->dev.of_node;
206 ret = lp8788_iio_map_register(indio_dev, lp->pdata, adc);
207 if (ret)
208 return ret;
209
210 mutex_init(&adc->lock);
211
212 indio_dev->dev.parent = &pdev->dev;
213 indio_dev->name = pdev->name;
214 indio_dev->modes = INDIO_DIRECT_MODE;
215 indio_dev->info = &lp8788_adc_info;
216 indio_dev->channels = lp8788_adc_channels;
217 indio_dev->num_channels = ARRAY_SIZE(lp8788_adc_channels);
218
219 ret = iio_device_register(indio_dev);
220 if (ret) {
221 dev_err(&pdev->dev, "iio dev register err: %d\n", ret);
222 goto err_iio_device;
223 }
224
225 return 0;
226
227err_iio_device:
228 iio_map_array_unregister(indio_dev);
229 return ret;
230}
231
232static int lp8788_adc_remove(struct platform_device *pdev)
233{
234 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
235
236 iio_device_unregister(indio_dev);
237 iio_map_array_unregister(indio_dev);
238
239 return 0;
240}
241
242static struct platform_driver lp8788_adc_driver = {
243 .probe = lp8788_adc_probe,
244 .remove = lp8788_adc_remove,
245 .driver = {
246 .name = LP8788_DEV_ADC,
247 },
248};
249module_platform_driver(lp8788_adc_driver);
250
251MODULE_DESCRIPTION("Texas Instruments LP8788 ADC Driver");
252MODULE_AUTHOR("Milo Kim");
253MODULE_LICENSE("GPL");
254MODULE_ALIAS("platform:lp8788-adc");
255
