1 // SPDX-License-Identifier: GPL-2.0+
3  * vz89x.c - Support for SGX Sensortech MiCS VZ89X VOC sensors
5  * Copyright (C) 2015-2018
93 		.scan_index = -1,
123 		.scan_index = -1,
152 	if (data->buffer[VZ89X_VOC_SHORT_IDX] == 0)  in vz89x_measurement_is_valid()
155 	return !!(data->buffer[data->chip->read_size - 1] > 0);  in vz89x_measurement_is_valid()
158 /* VZ89TE device has a modified CRC-8 two complement check */
164 	for (i = 0; i < (data->chip->read_size - 1); i++) {  in vz89te_measurement_is_valid()
165 		sum = crc + data->buffer[i];  in vz89te_measurement_is_valid()
170 	return !((0xff - crc) == data->buffer[data->chip->read_size - 1]);  in vz89te_measurement_is_valid()
175 	const struct vz89x_chip_data *chip = data->chip;  in vz89x_i2c_xfer()
176 	struct i2c_client *client = data->client;  in vz89x_i2c_xfer()
181 	msg[0].addr = client->addr;  in vz89x_i2c_xfer()
182 	msg[0].flags = client->flags;  in vz89x_i2c_xfer()
183 	msg[0].len = chip->write_size;  in vz89x_i2c_xfer()
186 	msg[1].addr = client->addr;  in vz89x_i2c_xfer()
187 	msg[1].flags = client->flags | I2C_M_RD;  in vz89x_i2c_xfer()
188 	msg[1].len = chip->read_size;  in vz89x_i2c_xfer()
189 	msg[1].buf = (char *) &data->buffer;  in vz89x_i2c_xfer()
191 	ret = i2c_transfer(client->adapter, msg, 2);  in vz89x_i2c_xfer()
198 	struct i2c_client *client = data->client;  in vz89x_smbus_xfer()
206 	for (i = 0; i < data->chip->read_size; i++) {  in vz89x_smbus_xfer()
210 		data->buffer[i] = ret;  in vz89x_smbus_xfer()
218 	const struct vz89x_chip_data *chip = data->chip;  in vz89x_get_measurement()
221 	/* sensor can only be polled once a second max per datasheet */  in vz89x_get_measurement()
222 	if (!time_after(jiffies, data->last_update + HZ))  in vz89x_get_measurement()
223 		return data->is_valid ? 0 : -EAGAIN;  in vz89x_get_measurement()
225 	data->is_valid = false;  in vz89x_get_measurement()
226 	data->last_update = jiffies;  in vz89x_get_measurement()
228 	ret = data->xfer(data, chip->cmd);  in vz89x_get_measurement()
232 	ret = chip->valid(data);  in vz89x_get_measurement()
234 		return -EAGAIN;  in vz89x_get_measurement()
236 	data->is_valid = true;  in vz89x_get_measurement()
245 	u8 *tmp = &data->buffer[chan->address];  in vz89x_get_resistance_reading()
247 	switch (chan->scan_type.endianness) {  in vz89x_get_resistance_reading()
255 		return -EINVAL;  in vz89x_get_resistance_reading()
266 	int ret = -EINVAL;  in vz89x_read_raw()
270 		mutex_lock(&data->lock);  in vz89x_read_raw()
272 		mutex_unlock(&data->lock);  in vz89x_read_raw()
277 		switch (chan->type) {  in vz89x_read_raw()
279 			*val = data->buffer[chan->address];  in vz89x_read_raw()
287 			return -EINVAL;  in vz89x_read_raw()
291 		switch (chan->type) {  in vz89x_read_raw()
296 			return -EINVAL;  in vz89x_read_raw()
300 		switch (chan->channel2) {  in vz89x_read_raw()
306 			*val = -13;  in vz89x_read_raw()
309 			return -EINVAL;  in vz89x_read_raw()
353 	struct device *dev = &client->dev;  in vz89x_probe()
359 		return -ENOMEM;  in vz89x_probe()
362 	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C))  in vz89x_probe()
363 		data->xfer = vz89x_i2c_xfer;  in vz89x_probe()
364 	else if (i2c_check_functionality(client->adapter,  in vz89x_probe()
366 		data->xfer = vz89x_smbus_xfer;  in vz89x_probe()
368 		return -EOPNOTSUPP;  in vz89x_probe()
370 	data->chip = i2c_get_match_data(client);  in vz89x_probe()
373 	data->client = client;  in vz89x_probe()
374 	data->last_update = jiffies - HZ;  in vz89x_probe()
375 	mutex_init(&data->lock);  in vz89x_probe()
377 	indio_dev->info = &vz89x_info;  in vz89x_probe()
378 	indio_dev->name = dev_name(dev);  in vz89x_probe()
379 	indio_dev->modes = INDIO_DIRECT_MODE;  in vz89x_probe()
381 	indio_dev->channels = data->chip->channels;  in vz89x_probe()
382 	indio_dev->num_channels = data->chip->num_channels;  in vz89x_probe()
405 MODULE_DESCRIPTION("SGX Sensortech MiCS VZ89X VOC sensors");