| /* |
| * ROHM BH1710/BH1715/BH1721/BH1750/BH1751 ambient light sensor driver |
| * |
| * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * Data sheets: |
| * http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1710fvc-e.pdf |
| * http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1715fvc-e.pdf |
| * http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1721fvc-e.pdf |
| * http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1750fvi-e.pdf |
| * http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1751fvi-e.pdf |
| * |
| * 7-bit I2C slave addresses: |
| * 0x23 (ADDR pin low) |
| * 0x5C (ADDR pin high) |
| * |
| */ |
| |
| #include <linux/delay.h> |
| #include <linux/i2c.h> |
| #include <linux/iio/iio.h> |
| #include <linux/iio/sysfs.h> |
| #include <linux/module.h> |
| |
| #define BH1750_POWER_DOWN 0x00 |
| #define BH1750_ONE_TIME_H_RES_MODE 0x20 /* auto-mode for BH1721 */ |
| #define BH1750_CHANGE_INT_TIME_H_BIT 0x40 |
| #define BH1750_CHANGE_INT_TIME_L_BIT 0x60 |
| |
| enum { |
| BH1710, |
| BH1721, |
| BH1750, |
| }; |
| |
| struct bh1750_chip_info; |
| struct bh1750_data { |
| struct i2c_client *client; |
| struct mutex lock; |
| const struct bh1750_chip_info *chip_info; |
| u16 mtreg; |
| }; |
| |
| struct bh1750_chip_info { |
| u16 mtreg_min; |
| u16 mtreg_max; |
| u16 mtreg_default; |
| int mtreg_to_usec; |
| int mtreg_to_scale; |
| |
| /* |
| * For BH1710/BH1721 all possible integration time values won't fit |
| * into one page so displaying is limited to every second one. |
| * Note, that user can still write proper values which were not |
| * listed. |
| */ |
| int inc; |
| |
| u16 int_time_low_mask; |
| u16 int_time_high_mask; |
| }; |
| |
| static const struct bh1750_chip_info bh1750_chip_info_tbl[] = { |
| [BH1710] = { 140, 1022, 300, 400, 250000000, 2, 0x001F, 0x03E0 }, |
| [BH1721] = { 140, 1020, 300, 400, 250000000, 2, 0x0010, 0x03E0 }, |
| [BH1750] = { 31, 254, 69, 1740, 57500000, 1, 0x001F, 0x00E0 }, |
| }; |
| |
| static int bh1750_change_int_time(struct bh1750_data *data, int usec) |
| { |
| int ret; |
| u16 val; |
| u8 regval; |
| const struct bh1750_chip_info *chip_info = data->chip_info; |
| |
| if ((usec % chip_info->mtreg_to_usec) != 0) |
| return -EINVAL; |
| |
| val = usec / chip_info->mtreg_to_usec; |
| if (val < chip_info->mtreg_min || val > chip_info->mtreg_max) |
| return -EINVAL; |
| |
| ret = i2c_smbus_write_byte(data->client, BH1750_POWER_DOWN); |
| if (ret < 0) |
| return ret; |
| |
| regval = (val & chip_info->int_time_high_mask) >> 5; |
| ret = i2c_smbus_write_byte(data->client, |
| BH1750_CHANGE_INT_TIME_H_BIT | regval); |
| if (ret < 0) |
| return ret; |
| |
| regval = val & chip_info->int_time_low_mask; |
| ret = i2c_smbus_write_byte(data->client, |
| BH1750_CHANGE_INT_TIME_L_BIT | regval); |
| if (ret < 0) |
| return ret; |
| |
| data->mtreg = val; |
| |
| return 0; |
| } |
| |
| static int bh1750_read(struct bh1750_data *data, int *val) |
| { |
| int ret; |
| __be16 result; |
| const struct bh1750_chip_info *chip_info = data->chip_info; |
| unsigned long delay = chip_info->mtreg_to_usec * data->mtreg; |
| |
| /* |
| * BH1721 will enter continuous mode on receiving this command. |
| * Note, that this eliminates need for bh1750_resume(). |
| */ |
| ret = i2c_smbus_write_byte(data->client, BH1750_ONE_TIME_H_RES_MODE); |
| if (ret < 0) |
| return ret; |
| |
| usleep_range(delay + 15000, delay + 40000); |
| |
| ret = i2c_master_recv(data->client, (char *)&result, 2); |
| if (ret < 0) |
| return ret; |
| |
| *val = be16_to_cpu(result); |
| |
| return 0; |
| } |
| |
| static int bh1750_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int *val, int *val2, long mask) |
| { |
| int ret, tmp; |
| struct bh1750_data *data = iio_priv(indio_dev); |
| const struct bh1750_chip_info *chip_info = data->chip_info; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_RAW: |
| switch (chan->type) { |
| case IIO_LIGHT: |
| mutex_lock(&data->lock); |
| ret = bh1750_read(data, val); |
| mutex_unlock(&data->lock); |
| if (ret < 0) |
| return ret; |
| |
| return IIO_VAL_INT; |
| default: |
| return -EINVAL; |
| } |
| case IIO_CHAN_INFO_SCALE: |
| tmp = chip_info->mtreg_to_scale / data->mtreg; |
| *val = tmp / 1000000; |
| *val2 = tmp % 1000000; |
| return IIO_VAL_INT_PLUS_MICRO; |
| case IIO_CHAN_INFO_INT_TIME: |
| *val = 0; |
| *val2 = chip_info->mtreg_to_usec * data->mtreg; |
| return IIO_VAL_INT_PLUS_MICRO; |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static int bh1750_write_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int val, int val2, long mask) |
| { |
| int ret; |
| struct bh1750_data *data = iio_priv(indio_dev); |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_INT_TIME: |
| if (val != 0) |
| return -EINVAL; |
| |
| mutex_lock(&data->lock); |
| ret = bh1750_change_int_time(data, val2); |
| mutex_unlock(&data->lock); |
| return ret; |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static ssize_t bh1750_show_int_time_available(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| int i; |
| size_t len = 0; |
| struct bh1750_data *data = iio_priv(dev_to_iio_dev(dev)); |
| const struct bh1750_chip_info *chip_info = data->chip_info; |
| |
| for (i = chip_info->mtreg_min; i <= chip_info->mtreg_max; i += chip_info->inc) |
| len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ", |
| chip_info->mtreg_to_usec * i); |
| |
| buf[len - 1] = '\n'; |
| |
| return len; |
| } |
| |
| static IIO_DEV_ATTR_INT_TIME_AVAIL(bh1750_show_int_time_available); |
| |
| static struct attribute *bh1750_attributes[] = { |
| &iio_dev_attr_integration_time_available.dev_attr.attr, |
| NULL, |
| }; |
| |
| static const struct attribute_group bh1750_attribute_group = { |
| .attrs = bh1750_attributes, |
| }; |
| |
| static const struct iio_info bh1750_info = { |
| .driver_module = THIS_MODULE, |
| .attrs = &bh1750_attribute_group, |
| .read_raw = bh1750_read_raw, |
| .write_raw = bh1750_write_raw, |
| }; |
| |
| static const struct iio_chan_spec bh1750_channels[] = { |
| { |
| .type = IIO_LIGHT, |
| .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | |
| BIT(IIO_CHAN_INFO_SCALE) | |
| BIT(IIO_CHAN_INFO_INT_TIME) |
| } |
| }; |
| |
| static int bh1750_probe(struct i2c_client *client, |
| const struct i2c_device_id *id) |
| { |
| int ret, usec; |
| struct bh1750_data *data; |
| struct iio_dev *indio_dev; |
| |
| if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | |
| I2C_FUNC_SMBUS_WRITE_BYTE)) |
| return -EOPNOTSUPP; |
| |
| indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); |
| if (!indio_dev) |
| return -ENOMEM; |
| |
| data = iio_priv(indio_dev); |
| i2c_set_clientdata(client, indio_dev); |
| data->client = client; |
| data->chip_info = &bh1750_chip_info_tbl[id->driver_data]; |
| |
| usec = data->chip_info->mtreg_to_usec * data->chip_info->mtreg_default; |
| ret = bh1750_change_int_time(data, usec); |
| if (ret < 0) |
| return ret; |
| |
| mutex_init(&data->lock); |
| indio_dev->dev.parent = &client->dev; |
| indio_dev->info = &bh1750_info; |
| indio_dev->name = id->name; |
| indio_dev->channels = bh1750_channels; |
| indio_dev->num_channels = ARRAY_SIZE(bh1750_channels); |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| |
| return iio_device_register(indio_dev); |
| } |
| |
| static int bh1750_remove(struct i2c_client *client) |
| { |
| struct iio_dev *indio_dev = i2c_get_clientdata(client); |
| struct bh1750_data *data = iio_priv(indio_dev); |
| |
| iio_device_unregister(indio_dev); |
| |
| mutex_lock(&data->lock); |
| i2c_smbus_write_byte(client, BH1750_POWER_DOWN); |
| mutex_unlock(&data->lock); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int bh1750_suspend(struct device *dev) |
| { |
| int ret; |
| struct bh1750_data *data = |
| iio_priv(i2c_get_clientdata(to_i2c_client(dev))); |
| |
| /* |
| * This is mainly for BH1721 which doesn't enter power down |
| * mode automatically. |
| */ |
| mutex_lock(&data->lock); |
| ret = i2c_smbus_write_byte(data->client, BH1750_POWER_DOWN); |
| mutex_unlock(&data->lock); |
| |
| return ret; |
| } |
| |
| static SIMPLE_DEV_PM_OPS(bh1750_pm_ops, bh1750_suspend, NULL); |
| #define BH1750_PM_OPS (&bh1750_pm_ops) |
| #else |
| #define BH1750_PM_OPS NULL |
| #endif |
| |
| static const struct i2c_device_id bh1750_id[] = { |
| { "bh1710", BH1710 }, |
| { "bh1715", BH1750 }, |
| { "bh1721", BH1721 }, |
| { "bh1750", BH1750 }, |
| { "bh1751", BH1750 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, bh1750_id); |
| |
| static struct i2c_driver bh1750_driver = { |
| .driver = { |
| .name = "bh1750", |
| .pm = BH1750_PM_OPS, |
| }, |
| .probe = bh1750_probe, |
| .remove = bh1750_remove, |
| .id_table = bh1750_id, |
| |
| }; |
| module_i2c_driver(bh1750_driver); |
| |
| MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>"); |
| MODULE_DESCRIPTION("ROHM BH1710/BH1715/BH1721/BH1750/BH1751 als driver"); |
| MODULE_LICENSE("GPL v2"); |