1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/array_size.h>
3 #include <linux/bitfield.h>
4 #include <linux/device.h>
5 #include <linux/err.h>
6 #include <linux/i2c.h>
7 #include <linux/mod_devicetable.h>
8 #include <linux/module.h>
9 #include <linux/pm.h>
10 #include <linux/regmap.h>
11 #include <linux/regulator/consumer.h>
12 #include <linux/types.h>
13
14 #include <linux/iio/iio.h>
15
16 #define AL3000A_REG_SYSTEM 0x00
17 #define AL3000A_REG_DATA 0x05
18
19 #define AL3000A_CONFIG_ENABLE 0x00
20 #define AL3000A_CONFIG_DISABLE 0x0b
21 #define AL3000A_CONFIG_RESET 0x0f
22 #define AL3000A_GAIN_MASK GENMASK(5, 0)
23
24 /*
25 * These are pre-calculated lux values based on possible output of sensor
26 * (range 0x00 - 0x3F)
27 */
28 static const u32 lux_table[] = {
29 1, 1, 1, 2, 2, 2, 3, 4, /* 0 - 7 */
30 4, 5, 6, 7, 9, 11, 13, 16, /* 8 - 15 */
31 19, 22, 27, 32, 39, 46, 56, 67, /* 16 - 23 */
32 80, 96, 116, 139, 167, 200, 240, 289, /* 24 - 31 */
33 347, 416, 499, 600, 720, 864, 1037, 1245, /* 32 - 39 */
34 1495, 1795, 2155, 2587, 3105, 3728, 4475, 5373, /* 40 - 47 */
35 6450, 7743, 9296, 11160, 13397, 16084, 19309, 23180, /* 48 - 55 */
36 27828, 33408, 40107, 48148, 57803, 69393, 83306, 100000 /* 56 - 63 */
37 };
38
39 static const struct regmap_config al3000a_regmap_config = {
40 .reg_bits = 8,
41 .val_bits = 8,
42 .max_register = AL3000A_REG_DATA,
43 };
44
45 struct al3000a_data {
46 struct regmap *regmap;
47 struct regulator *vdd_supply;
48 };
49
50 static const struct iio_chan_spec al3000a_channels[] = {
51 {
52 .type = IIO_LIGHT,
53 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
54 },
55 };
56
al3000a_set_pwr_on(struct al3000a_data * data)57 static int al3000a_set_pwr_on(struct al3000a_data *data)
58 {
59 struct device *dev = regmap_get_device(data->regmap);
60 int ret;
61
62 ret = regulator_enable(data->vdd_supply);
63 if (ret) {
64 dev_err(dev, "failed to enable vdd power supply\n");
65 return ret;
66 }
67
68 return regmap_write(data->regmap, AL3000A_REG_SYSTEM, AL3000A_CONFIG_ENABLE);
69 }
70
al3000a_set_pwr_off(void * _data)71 static void al3000a_set_pwr_off(void *_data)
72 {
73 struct al3000a_data *data = _data;
74 struct device *dev = regmap_get_device(data->regmap);
75 int ret;
76
77 ret = regmap_write(data->regmap, AL3000A_REG_SYSTEM, AL3000A_CONFIG_DISABLE);
78 if (ret)
79 dev_err(dev, "failed to write system register\n");
80
81 ret = regulator_disable(data->vdd_supply);
82 if (ret)
83 dev_err(dev, "failed to disable vdd power supply\n");
84 }
85
al3000a_init(struct al3000a_data * data)86 static int al3000a_init(struct al3000a_data *data)
87 {
88 int ret;
89
90 ret = al3000a_set_pwr_on(data);
91 if (ret)
92 return ret;
93
94 ret = regmap_write(data->regmap, AL3000A_REG_SYSTEM, AL3000A_CONFIG_RESET);
95 if (ret)
96 return ret;
97
98 return regmap_write(data->regmap, AL3000A_REG_SYSTEM, AL3000A_CONFIG_ENABLE);
99 }
100
al3000a_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)101 static int al3000a_read_raw(struct iio_dev *indio_dev,
102 struct iio_chan_spec const *chan, int *val,
103 int *val2, long mask)
104 {
105 struct al3000a_data *data = iio_priv(indio_dev);
106 int ret, gain;
107
108 switch (mask) {
109 case IIO_CHAN_INFO_PROCESSED:
110 ret = regmap_read(data->regmap, AL3000A_REG_DATA, &gain);
111 if (ret)
112 return ret;
113
114 *val = lux_table[gain & AL3000A_GAIN_MASK];
115
116 return IIO_VAL_INT;
117 default:
118 return -EINVAL;
119 }
120 }
121
122 static const struct iio_info al3000a_info = {
123 .read_raw = al3000a_read_raw,
124 };
125
al3000a_probe(struct i2c_client * client)126 static int al3000a_probe(struct i2c_client *client)
127 {
128 struct al3000a_data *data;
129 struct device *dev = &client->dev;
130 struct iio_dev *indio_dev;
131 int ret;
132
133 indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
134 if (!indio_dev)
135 return -ENOMEM;
136
137 data = iio_priv(indio_dev);
138 i2c_set_clientdata(client, indio_dev);
139
140 data->regmap = devm_regmap_init_i2c(client, &al3000a_regmap_config);
141 if (IS_ERR(data->regmap))
142 return dev_err_probe(dev, PTR_ERR(data->regmap),
143 "cannot allocate regmap\n");
144
145 data->vdd_supply = devm_regulator_get(dev, "vdd");
146 if (IS_ERR(data->vdd_supply))
147 return dev_err_probe(dev, PTR_ERR(data->vdd_supply),
148 "failed to get vdd regulator\n");
149
150 indio_dev->info = &al3000a_info;
151 indio_dev->name = "al3000a";
152 indio_dev->channels = al3000a_channels;
153 indio_dev->num_channels = ARRAY_SIZE(al3000a_channels);
154 indio_dev->modes = INDIO_DIRECT_MODE;
155
156 ret = al3000a_init(data);
157 if (ret)
158 return dev_err_probe(dev, ret, "failed to init ALS\n");
159
160 ret = devm_add_action_or_reset(dev, al3000a_set_pwr_off, data);
161 if (ret)
162 return dev_err_probe(dev, ret, "failed to add action\n");
163
164 return devm_iio_device_register(dev, indio_dev);
165 }
166
al3000a_suspend(struct device * dev)167 static int al3000a_suspend(struct device *dev)
168 {
169 struct al3000a_data *data = iio_priv(dev_get_drvdata(dev));
170
171 al3000a_set_pwr_off(data);
172 return 0;
173 }
174
al3000a_resume(struct device * dev)175 static int al3000a_resume(struct device *dev)
176 {
177 struct al3000a_data *data = iio_priv(dev_get_drvdata(dev));
178
179 return al3000a_set_pwr_on(data);
180 }
181
182 static DEFINE_SIMPLE_DEV_PM_OPS(al3000a_pm_ops, al3000a_suspend, al3000a_resume);
183
184 static const struct i2c_device_id al3000a_id[] = {
185 { "al3000a" },
186 { }
187 };
188 MODULE_DEVICE_TABLE(i2c, al3000a_id);
189
190 static const struct of_device_id al3000a_of_match[] = {
191 { .compatible = "dynaimage,al3000a" },
192 { /* sentinel */ }
193 };
194 MODULE_DEVICE_TABLE(of, al3000a_of_match);
195
196 static struct i2c_driver al3000a_driver = {
197 .driver = {
198 .name = "al3000a",
199 .of_match_table = al3000a_of_match,
200 .pm = pm_sleep_ptr(&al3000a_pm_ops),
201 },
202 .probe = al3000a_probe,
203 .id_table = al3000a_id,
204 };
205 module_i2c_driver(al3000a_driver);
206
207 MODULE_AUTHOR("Svyatolsav Ryhel <clamor95@gmail.com>");
208 MODULE_DESCRIPTION("al3000a Ambient Light Sensor driver");
209 MODULE_LICENSE("GPL");
210