1 // SPDX-License-Identifier: GPL-2.0
3  * max44009.c - Support for MAX44009 Ambient Light Sensor
7  * Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX44009.pdf
31 #define MAX44009_REG_CFG 0x2
51 /* The max44009 always scales raw readings by 0.045 and is non-configurable */
55 /* The fixed-point fractional multiplier for de-scaling threshold values */
112 	int ret = i2c_smbus_read_byte_data(data->client, MAX44009_REG_CFG);  in max44009_read_int_time()
123 	struct i2c_client *client = data->client;  in max44009_write_int_time()
156 	if (mask == IIO_CHAN_INFO_INT_TIME && chan->type == IIO_LIGHT) {  in max44009_write_raw()
157 		mutex_lock(&data->lock);  in max44009_write_raw()
159 		mutex_unlock(&data->lock);  in max44009_write_raw()
162 	return -EINVAL;  in max44009_write_raw()
172 static int max44009_lux_raw(u8 hi, u8 lo)  in max44009_lux_raw()  argument
181 	mantissa = ((hi & 0xf) << 4) | (lo & 0xf);  in max44009_lux_raw()
201 	u8 lo = 0;  in max44009_read_lux_raw()  local
206 			.addr = data->client->addr,  in max44009_read_lux_raw()
212 			.addr = data->client->addr,  in max44009_read_lux_raw()
218 			.addr = data->client->addr,  in max44009_read_lux_raw()
224 			.addr = data->client->addr,  in max44009_read_lux_raw()
226 			.len = sizeof(lo),  in max44009_read_lux_raw()
227 			.buf = &lo,  in max44009_read_lux_raw()
237 	ret = i2c_transfer(data->client->adapter,  in max44009_read_lux_raw()
241 		return -EIO;  in max44009_read_lux_raw()
243 	return max44009_lux_raw(hi, lo);  in max44009_read_lux_raw()
256 		switch (chan->type) {  in max44009_read_raw()
267 			return -EINVAL;  in max44009_read_raw()
270 		switch (chan->type) {  in max44009_read_raw()
280 			return -EINVAL;  in max44009_read_raw()
283 		return -EINVAL;  in max44009_read_raw()
306 		return -EINVAL;  in max44009_threshold_byte_from_fraction()
308 	/* Reverse scaling of fixed-point integral */  in max44009_threshold_byte_from_fraction()
312 	/* Reverse scaling of fixed-point fractional */  in max44009_threshold_byte_from_fraction()
334 		return -EINVAL;  in max44009_get_thr_reg()
348 	if (info != IIO_EV_INFO_VALUE || chan->type != IIO_LIGHT)  in max44009_write_event_value()
349 		return -EINVAL;  in max44009_write_event_value()
359 	return i2c_smbus_write_byte_data(data->client, reg, threshold);  in max44009_write_event_value()
373 	byte = i2c_smbus_read_byte_data(data->client, reg);  in max44009_read_threshold()
407 	if (chan->type != IIO_LIGHT || type != IIO_EV_TYPE_THRESH)  in max44009_read_event_value()
408 		return -EINVAL;  in max44009_read_event_value()
430 	if (chan->type != IIO_LIGHT || type != IIO_EV_TYPE_THRESH)  in max44009_write_event_config()
431 		return -EINVAL;  in max44009_write_event_config()
433 	ret = i2c_smbus_write_byte_data(data->client,  in max44009_write_event_config()
442 	return i2c_smbus_write_byte_data(data->client,  in max44009_write_event_config()
453 	if (chan->type != IIO_LIGHT || type != IIO_EV_TYPE_THRESH)  in max44009_read_event_config()
454 		return -EINVAL;  in max44009_read_event_config()
456 	return i2c_smbus_read_byte_data(data->client, MAX44009_REG_INT_EN);  in max44009_read_event_config()
476 	ret = i2c_smbus_read_byte_data(data->client, MAX44009_REG_INT_STATUS);  in max44009_threaded_irq_handler()
497 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));  in max44009_probe()
499 		return -ENOMEM;  in max44009_probe()
503 	data->client = client;  in max44009_probe()
504 	indio_dev->info = &max44009_info;  in max44009_probe()
505 	indio_dev->modes = INDIO_DIRECT_MODE;  in max44009_probe()
506 	indio_dev->name = MAX44009_DRV_NAME;  in max44009_probe()
507 	indio_dev->channels = max44009_channels;  in max44009_probe()
508 	indio_dev->num_channels = ARRAY_SIZE(max44009_channels);  in max44009_probe()
509 	mutex_init(&data->lock);  in max44009_probe()
516 	if (client->irq > 0) {  in max44009_probe()
517 		ret = devm_request_threaded_irq(&client->dev, client->irq,  in max44009_probe()
528 	return devm_iio_device_register(&client->dev, indio_dev);  in max44009_probe()