1 // SPDX-License-Identifier: GPL-2.0
3  * ROHM BH1710/BH1715/BH1721/BH1750/BH1751 ambient light sensor driver
8  *  http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1710fvc-e.pdf
9  *  http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1715fvc-e.pdf
10  *  http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1721fvc-e.pdf
11  *  http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1750fvi-e.pdf
12  *  http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1751fvi-e.pdf
14  * 7-bit I2C slave addresses:
27 #define BH1750_ONE_TIME_H_RES_MODE	0x20 /* auto-mode for BH1721 */
75 	const struct bh1750_chip_info *chip_info = data->chip_info;  in bh1750_change_int_time()
77 	if ((usec % chip_info->mtreg_to_usec) != 0)  in bh1750_change_int_time()
78 		return -EINVAL;  in bh1750_change_int_time()
80 	val = usec / chip_info->mtreg_to_usec;  in bh1750_change_int_time()
81 	if (val < chip_info->mtreg_min || val > chip_info->mtreg_max)  in bh1750_change_int_time()
82 		return -EINVAL;  in bh1750_change_int_time()
84 	ret = i2c_smbus_write_byte(data->client, BH1750_POWER_DOWN);  in bh1750_change_int_time()
88 	regval = (val & chip_info->int_time_high_mask) >> 5;  in bh1750_change_int_time()
89 	ret = i2c_smbus_write_byte(data->client,  in bh1750_change_int_time()
94 	regval = val & chip_info->int_time_low_mask;  in bh1750_change_int_time()
95 	ret = i2c_smbus_write_byte(data->client,  in bh1750_change_int_time()
100 	data->mtreg = val;  in bh1750_change_int_time()
109 	const struct bh1750_chip_info *chip_info = data->chip_info;  in bh1750_read()
110 	unsigned long delay = chip_info->mtreg_to_usec * data->mtreg;  in bh1750_read()
116 	ret = i2c_smbus_write_byte(data->client, BH1750_ONE_TIME_H_RES_MODE);  in bh1750_read()
122 	ret = i2c_master_recv(data->client, (char *)&result, 2);  in bh1750_read()
137 	const struct bh1750_chip_info *chip_info = data->chip_info;  in bh1750_read_raw()
141 		switch (chan->type) {  in bh1750_read_raw()
143 			mutex_lock(&data->lock);  in bh1750_read_raw()
145 			mutex_unlock(&data->lock);  in bh1750_read_raw()
151 			return -EINVAL;  in bh1750_read_raw()
154 		tmp = chip_info->mtreg_to_scale / data->mtreg;  in bh1750_read_raw()
160 		*val2 = chip_info->mtreg_to_usec * data->mtreg;  in bh1750_read_raw()
163 		return -EINVAL;  in bh1750_read_raw()
177 			return -EINVAL;  in bh1750_write_raw()
179 		mutex_lock(&data->lock);  in bh1750_write_raw()
181 		mutex_unlock(&data->lock);  in bh1750_write_raw()
184 		return -EINVAL;  in bh1750_write_raw()
194 	const struct bh1750_chip_info *chip_info = data->chip_info;  in bh1750_show_int_time_available()
196 	for (i = chip_info->mtreg_min; i <= chip_info->mtreg_max; i += chip_info->inc)  in bh1750_show_int_time_available()
197 		len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ",  in bh1750_show_int_time_available()
198 				 chip_info->mtreg_to_usec * i);  in bh1750_show_int_time_available()
200 	buf[len - 1] = '\n';  in bh1750_show_int_time_available()
238 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |  in bh1750_probe()
240 		return -EOPNOTSUPP;  in bh1750_probe()
242 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));  in bh1750_probe()
244 		return -ENOMEM;  in bh1750_probe()
248 	data->client = client;  in bh1750_probe()
249 	data->chip_info = &bh1750_chip_info_tbl[id->driver_data];  in bh1750_probe()
251 	usec = data->chip_info->mtreg_to_usec * data->chip_info->mtreg_default;  in bh1750_probe()
256 	mutex_init(&data->lock);  in bh1750_probe()
257 	indio_dev->info = &bh1750_info;  in bh1750_probe()
258 	indio_dev->name = id->name;  in bh1750_probe()
259 	indio_dev->channels = bh1750_channels;  in bh1750_probe()
260 	indio_dev->num_channels = ARRAY_SIZE(bh1750_channels);  in bh1750_probe()
261 	indio_dev->modes = INDIO_DIRECT_MODE;  in bh1750_probe()
273 	mutex_lock(&data->lock);  in bh1750_remove()
275 	mutex_unlock(&data->lock);  in bh1750_remove()
288 	mutex_lock(&data->lock);  in bh1750_suspend()
289 	ret = i2c_smbus_write_byte(data->client, BH1750_POWER_DOWN);  in bh1750_suspend()
290 	mutex_unlock(&data->lock);  in bh1750_suspend()