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 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 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 86 static int al3000a_init(struct al3000a_data *data) 87 { 88 struct device *dev = regmap_get_device(data->regmap); 89 int ret; 90 91 ret = al3000a_set_pwr_on(data); 92 if (ret) 93 return ret; 94 95 ret = devm_add_action_or_reset(dev, al3000a_set_pwr_off, data); 96 if (ret) 97 return dev_err_probe(dev, ret, "failed to add action\n"); 98 99 ret = regmap_write(data->regmap, AL3000A_REG_SYSTEM, AL3000A_CONFIG_RESET); 100 if (ret) 101 return ret; 102 103 return regmap_write(data->regmap, AL3000A_REG_SYSTEM, AL3000A_CONFIG_ENABLE); 104 } 105 106 static int al3000a_read_raw(struct iio_dev *indio_dev, 107 struct iio_chan_spec const *chan, int *val, 108 int *val2, long mask) 109 { 110 struct al3000a_data *data = iio_priv(indio_dev); 111 int ret, gain; 112 113 switch (mask) { 114 case IIO_CHAN_INFO_PROCESSED: 115 ret = regmap_read(data->regmap, AL3000A_REG_DATA, &gain); 116 if (ret) 117 return ret; 118 119 *val = lux_table[gain & AL3000A_GAIN_MASK]; 120 121 return IIO_VAL_INT; 122 default: 123 return -EINVAL; 124 } 125 } 126 127 static const struct iio_info al3000a_info = { 128 .read_raw = al3000a_read_raw, 129 }; 130 131 static int al3000a_probe(struct i2c_client *client) 132 { 133 struct al3000a_data *data; 134 struct device *dev = &client->dev; 135 struct iio_dev *indio_dev; 136 int ret; 137 138 indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); 139 if (!indio_dev) 140 return -ENOMEM; 141 142 data = iio_priv(indio_dev); 143 i2c_set_clientdata(client, indio_dev); 144 145 data->regmap = devm_regmap_init_i2c(client, &al3000a_regmap_config); 146 if (IS_ERR(data->regmap)) 147 return dev_err_probe(dev, PTR_ERR(data->regmap), 148 "cannot allocate regmap\n"); 149 150 data->vdd_supply = devm_regulator_get(dev, "vdd"); 151 if (IS_ERR(data->vdd_supply)) 152 return dev_err_probe(dev, PTR_ERR(data->vdd_supply), 153 "failed to get vdd regulator\n"); 154 155 indio_dev->info = &al3000a_info; 156 indio_dev->name = "al3000a"; 157 indio_dev->channels = al3000a_channels; 158 indio_dev->num_channels = ARRAY_SIZE(al3000a_channels); 159 indio_dev->modes = INDIO_DIRECT_MODE; 160 161 ret = al3000a_init(data); 162 if (ret) 163 return dev_err_probe(dev, ret, "failed to init ALS\n"); 164 165 return devm_iio_device_register(dev, indio_dev); 166 } 167 168 static int al3000a_suspend(struct device *dev) 169 { 170 struct al3000a_data *data = iio_priv(dev_get_drvdata(dev)); 171 172 al3000a_set_pwr_off(data); 173 return 0; 174 } 175 176 static int al3000a_resume(struct device *dev) 177 { 178 struct al3000a_data *data = iio_priv(dev_get_drvdata(dev)); 179 180 return al3000a_set_pwr_on(data); 181 } 182 183 static DEFINE_SIMPLE_DEV_PM_OPS(al3000a_pm_ops, al3000a_suspend, al3000a_resume); 184 185 static const struct i2c_device_id al3000a_id[] = { 186 { "al3000a" }, 187 { } 188 }; 189 MODULE_DEVICE_TABLE(i2c, al3000a_id); 190 191 static const struct of_device_id al3000a_of_match[] = { 192 { .compatible = "dynaimage,al3000a" }, 193 { } 194 }; 195 MODULE_DEVICE_TABLE(of, al3000a_of_match); 196 197 static struct i2c_driver al3000a_driver = { 198 .driver = { 199 .name = "al3000a", 200 .of_match_table = al3000a_of_match, 201 .pm = pm_sleep_ptr(&al3000a_pm_ops), 202 }, 203 .probe = al3000a_probe, 204 .id_table = al3000a_id, 205 }; 206 module_i2c_driver(al3000a_driver); 207 208 MODULE_AUTHOR("Svyatolsav Ryhel <clamor95@gmail.com>"); 209 MODULE_DESCRIPTION("al3000a Ambient Light Sensor driver"); 210 MODULE_LICENSE("GPL"); 211