// SPDX-License-Identifier: GPL-2.0+ /* * Support for ON Semiconductor NOA1305 ambient light sensor * * Copyright (C) 2016 Emcraft Systems * Copyright (C) 2019 Collabora Ltd. */ #include <linux/delay.h> #include <linux/err.h> #include <linux/i2c.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> #include <linux/module.h> #include <linux/regmap.h> #include <linux/regulator/consumer.h> #define NOA1305_REG_POWER_CONTROL 0x0 #define NOA1305_POWER_CONTROL_DOWN 0x00 #define NOA1305_POWER_CONTROL_ON 0x08 #define NOA1305_REG_RESET 0x1 #define NOA1305_RESET_RESET 0x10 #define NOA1305_REG_INTEGRATION_TIME 0x2 #define NOA1305_INTEGR_TIME_800MS 0x00 #define NOA1305_INTEGR_TIME_400MS 0x01 #define NOA1305_INTEGR_TIME_200MS 0x02 #define NOA1305_INTEGR_TIME_100MS 0x03 #define NOA1305_INTEGR_TIME_50MS 0x04 #define NOA1305_INTEGR_TIME_25MS 0x05 #define NOA1305_INTEGR_TIME_12_5MS 0x06 #define NOA1305_INTEGR_TIME_6_25MS 0x07 #define NOA1305_REG_INT_SELECT 0x3 #define NOA1305_INT_SEL_ACTIVE_HIGH 0x01 #define NOA1305_INT_SEL_ACTIVE_LOW 0x02 #define NOA1305_INT_SEL_INACTIVE 0x03 #define NOA1305_REG_INT_THRESH_LSB 0x4 #define NOA1305_REG_INT_THRESH_MSB 0x5 #define NOA1305_REG_ALS_DATA_LSB 0x6 #define NOA1305_REG_ALS_DATA_MSB 0x7 #define NOA1305_REG_DEVICE_ID_LSB 0x8 #define NOA1305_REG_DEVICE_ID_MSB 0x9 #define NOA1305_DEVICE_ID 0x0519 #define NOA1305_DRIVER_NAME "noa1305" struct noa1305_priv { struct i2c_client *client; struct regmap *regmap; }; static int noa1305_measure(struct noa1305_priv *priv) { __le16 data; int ret; ret = regmap_bulk_read(priv->regmap, NOA1305_REG_ALS_DATA_LSB, &data, 2); if (ret < 0) return ret; return le16_to_cpu(data); } static int noa1305_scale(struct noa1305_priv *priv, int *val, int *val2) { int data; int ret; ret = regmap_read(priv->regmap, NOA1305_REG_INTEGRATION_TIME, &data); if (ret < 0) return ret; /* * Lux = count / (<Integration Constant> * <Integration Time>) * * Integration Constant = 7.7 * Integration Time in Seconds */ switch (data) { case NOA1305_INTEGR_TIME_800MS: *val = 100; *val2 = 77 * 8; break; case NOA1305_INTEGR_TIME_400MS: *val = 100; *val2 = 77 * 4; break; case NOA1305_INTEGR_TIME_200MS: *val = 100; *val2 = 77 * 2; break; case NOA1305_INTEGR_TIME_100MS: *val = 100; *val2 = 77; break; case NOA1305_INTEGR_TIME_50MS: *val = 1000; *val2 = 77 * 5; break; case NOA1305_INTEGR_TIME_25MS: *val = 10000; *val2 = 77 * 25; break; case NOA1305_INTEGR_TIME_12_5MS: *val = 100000; *val2 = 77 * 125; break; case NOA1305_INTEGR_TIME_6_25MS: *val = 1000000; *val2 = 77 * 625; break; default: return -EINVAL; } return IIO_VAL_FRACTIONAL; } static const struct iio_chan_spec noa1305_channels[] = { { .type = IIO_LIGHT, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), } }; static int noa1305_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { int ret = -EINVAL; struct noa1305_priv *priv = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_RAW: switch (chan->type) { case IIO_LIGHT: ret = noa1305_measure(priv); if (ret < 0) return ret; *val = ret; return IIO_VAL_INT; default: break; } break; case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_LIGHT: return noa1305_scale(priv, val, val2); default: break; } break; default: break; } return ret; } static const struct iio_info noa1305_info = { .read_raw = noa1305_read_raw, }; static bool noa1305_writable_reg(struct device *dev, unsigned int reg) { switch (reg) { case NOA1305_REG_POWER_CONTROL: case NOA1305_REG_RESET: case NOA1305_REG_INTEGRATION_TIME: case NOA1305_REG_INT_SELECT: case NOA1305_REG_INT_THRESH_LSB: case NOA1305_REG_INT_THRESH_MSB: return true; default: return false; } } static const struct regmap_config noa1305_regmap_config = { .name = NOA1305_DRIVER_NAME, .reg_bits = 8, .val_bits = 8, .max_register = NOA1305_REG_DEVICE_ID_MSB, .writeable_reg = noa1305_writable_reg, }; static int noa1305_probe(struct i2c_client *client) { struct noa1305_priv *priv; struct iio_dev *indio_dev; struct regmap *regmap; __le16 data; unsigned int dev_id; int ret; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*priv)); if (!indio_dev) return -ENOMEM; regmap = devm_regmap_init_i2c(client, &noa1305_regmap_config); if (IS_ERR(regmap)) { dev_err(&client->dev, "Regmap initialization failed.\n"); return PTR_ERR(regmap); } priv = iio_priv(indio_dev); ret = devm_regulator_get_enable(&client->dev, "vin"); if (ret) return dev_err_probe(&client->dev, ret, "get regulator vin failed\n"); i2c_set_clientdata(client, indio_dev); priv->client = client; priv->regmap = regmap; ret = regmap_bulk_read(regmap, NOA1305_REG_DEVICE_ID_LSB, &data, 2); if (ret < 0) { dev_err(&client->dev, "ID reading failed: %d\n", ret); return ret; } dev_id = le16_to_cpu(data); if (dev_id != NOA1305_DEVICE_ID) { dev_err(&client->dev, "Unknown device ID: 0x%x\n", dev_id); return -ENODEV; } ret = regmap_write(regmap, NOA1305_REG_POWER_CONTROL, NOA1305_POWER_CONTROL_ON); if (ret < 0) { dev_err(&client->dev, "Enabling power control failed\n"); return ret; } ret = regmap_write(regmap, NOA1305_REG_RESET, NOA1305_RESET_RESET); if (ret < 0) { dev_err(&client->dev, "Device reset failed\n"); return ret; } ret = regmap_write(regmap, NOA1305_REG_INTEGRATION_TIME, NOA1305_INTEGR_TIME_800MS); if (ret < 0) { dev_err(&client->dev, "Setting integration time failed\n"); return ret; } indio_dev->info = &noa1305_info; indio_dev->channels = noa1305_channels; indio_dev->num_channels = ARRAY_SIZE(noa1305_channels); indio_dev->name = NOA1305_DRIVER_NAME; indio_dev->modes = INDIO_DIRECT_MODE; ret = devm_iio_device_register(&client->dev, indio_dev); if (ret) dev_err(&client->dev, "registering device failed\n"); return ret; } static const struct of_device_id noa1305_of_match[] = { { .compatible = "onnn,noa1305" }, { } }; MODULE_DEVICE_TABLE(of, noa1305_of_match); static const struct i2c_device_id noa1305_ids[] = { { "noa1305", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, noa1305_ids); static struct i2c_driver noa1305_driver = { .driver = { .name = NOA1305_DRIVER_NAME, .of_match_table = noa1305_of_match, }, .probe_new = noa1305_probe, .id_table = noa1305_ids, }; module_i2c_driver(noa1305_driver); MODULE_AUTHOR("Sergei Miroshnichenko <sergeimir@emcraft.com>"); MODULE_AUTHOR("Martyn Welch <martyn.welch@collabora.com"); MODULE_DESCRIPTION("ON Semiconductor NOA1305 ambient light sensor"); MODULE_LICENSE("GPL");