text: /* sensor_isl29035.c - driver for ISL29035 light sensor */
  
  /*
   * Copyright (c) 2016 Intel Corporation
   *
   * SPDX-License-Identifier: Apache-2.0
   */
  
  #include <kernel.h>
  #include <init.h>
  #include <i2c.h>
  #include <sensor.h>
  #include <misc/__assert.h>
  
  #include "isl29035.h"
  
  static int isl29035_sample_fetch(struct device *dev, enum sensor_channel chan)
  {
  	struct isl29035_driver_data *drv_data = dev->driver_data;
  	u8_t msb, lsb;
  
  	__ASSERT_NO_MSG(chan == SENSOR_CHAN_ALL);
  
  	if (i2c_reg_read_byte(drv_data->i2c, ISL29035_I2C_ADDRESS,
  				ISL29035_DATA_MSB_REG, &msb) < 0) {
  		return -EIO;
  	}
  
  	if (i2c_reg_read_byte(drv_data->i2c, ISL29035_I2C_ADDRESS,
  				ISL29035_DATA_LSB_REG, &lsb) < 0) {
  		return -EIO;
  	}
  
  	drv_data->data_sample = (msb << 8) + lsb;
  
  	return 0;
  }
  
  static int isl29035_channel_get(struct device *dev,
  				enum sensor_channel chan,
  				struct sensor_value *val)
  {
  	struct isl29035_driver_data *drv_data = dev->driver_data;
  	u64_t tmp;
  
  #if CONFIG_ISL29035_MODE_ALS
  	/* val = sample_val * lux_range / (2 ^ adc_data_bits) */
  	tmp = (u64_t)drv_data->data_sample * ISL29035_LUX_RANGE;
  	val->val1 = tmp >> ISL29035_ADC_DATA_BITS;
  	tmp = (tmp & ISL29035_ADC_DATA_MASK) * 1000000;
  	val->val2 = tmp >> ISL29035_ADC_DATA_BITS;
  #elif CONFIG_ISL29035_MODE_IR
  	ARG_UNUSED(tmp);
  	val->val1 = drv_data->data_sample;
  	val->val2 = 0;
  #endif
  
  	return 0;
  }
  
  static const struct sensor_driver_api isl29035_api = {
  #if CONFIG_ISL29035_TRIGGER
  	.attr_set = &isl29035_attr_set,
  	.trigger_set = &isl29035_trigger_set,
  #endif
  	.sample_fetch = &isl29035_sample_fetch,
  	.channel_get = &isl29035_channel_get,
  };
  
  static int isl29035_init(struct device *dev)
  {
  	struct isl29035_driver_data *drv_data = dev->driver_data;
  
  	drv_data->i2c = device_get_binding(CONFIG_ISL29035_I2C_MASTER_DEV_NAME);
  	if (drv_data->i2c == NULL) {
  		SYS_LOG_DBG("Failed to get I2C device.");
  		return -EINVAL;
  	}
  
  	drv_data->data_sample = 0;
  
  	/* clear blownout status bit */
  	if (i2c_reg_update_byte(drv_data->i2c, ISL29035_I2C_ADDRESS,
  				ISL29035_ID_REG, ISL29035_BOUT_MASK, 0) < 0) {
  		SYS_LOG_DBG("Failed to clear blownout status bit.");
  		return -EIO;
  	}
  
  	/* set command registers to set default attributes */
  	if (i2c_reg_write_byte(drv_data->i2c, ISL29035_I2C_ADDRESS,
  			       ISL29035_COMMAND_I_REG, 0) < 0) {
  		SYS_LOG_DBG("Failed to clear COMMAND-I.");
  		return -EIO;
  	}
  
  	if (i2c_reg_write_byte(drv_data->i2c, ISL29035_I2C_ADDRESS,
  				 ISL29035_COMMAND_II_REG, 0) < 0) {
  		SYS_LOG_DBG("Failed to clear COMMAND-II.");
  		return -EIO;
  	}
  
  	/* set operation mode */
  	if (i2c_reg_update_byte(drv_data->i2c, ISL29035_I2C_ADDRESS,
  				  ISL29035_COMMAND_I_REG,
  				  ISL29035_OPMODE_MASK,
  				  ISL29035_ACTIVE_OPMODE_BITS) < 0) {
  		SYS_LOG_DBG("Failed to set opmode.");
  		return -EIO;
  	}
  
  	/* set lux range */
  	if (i2c_reg_update_byte(drv_data->i2c, ISL29035_I2C_ADDRESS,
  				ISL29035_COMMAND_II_REG,
  				ISL29035_LUX_RANGE_MASK,
  				ISL29035_LUX_RANGE_BITS) < 0) {
  		SYS_LOG_DBG("Failed to set lux range.");
  		return -EIO;
  	}
  
  	/* set ADC resolution */
  	if (i2c_reg_update_byte(drv_data->i2c, ISL29035_I2C_ADDRESS,
  				ISL29035_COMMAND_II_REG,
  				ISL29035_ADC_RES_MASK,
  				ISL29035_ADC_RES_BITS) < 0) {
  		SYS_LOG_DBG("Failed to set ADC resolution.");
  		return -EIO;
  	}
  
  #ifdef CONFIG_ISL29035_TRIGGER
  	if (isl29035_init_interrupt(dev) < 0) {
  		SYS_LOG_DBG("Failed to initialize interrupt.");
  		return -EIO;
  	}
  #endif
  
  	dev->driver_api = &isl29035_api;
  
  	return 0;
  }
  
  struct isl29035_driver_data isl29035_data;
  
  DEVICE_INIT(isl29035_dev, CONFIG_ISL29035_NAME, &isl29035_init,
  	    &isl29035_data, NULL, POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY);
  