diff options
Diffstat (limited to 'drivers/iio/light/noa1305.c')
| -rw-r--r-- | drivers/iio/light/noa1305.c | 311 |
1 files changed, 311 insertions, 0 deletions
diff --git a/drivers/iio/light/noa1305.c b/drivers/iio/light/noa1305.c new file mode 100644 index 000000000..ee81fe083 --- /dev/null +++ b/drivers/iio/light/noa1305.c @@ -0,0 +1,311 @@ +// 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; + struct regulator *vin_reg; +}; + +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 void noa1305_reg_remove(void *data) +{ + struct noa1305_priv *priv = data; + + regulator_disable(priv->vin_reg); +} + +static int noa1305_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + 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); + + priv->vin_reg = devm_regulator_get(&client->dev, "vin"); + if (IS_ERR(priv->vin_reg)) + return dev_err_probe(&client->dev, PTR_ERR(priv->vin_reg), + "get regulator vin failed\n"); + + ret = regulator_enable(priv->vin_reg); + if (ret) { + dev_err(&client->dev, "enable regulator vin failed\n"); + return ret; + } + + ret = devm_add_action_or_reset(&client->dev, noa1305_reg_remove, priv); + if (ret) { + dev_err(&client->dev, "addition of devm action failed\n"); + return ret; + } + + 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 = 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"); |