/**************************************************************************** * drivers/sensors/adxl345_i2c.c * * Copyright (C) 2014 Alan Carvalho de Assis. All rights reserved. * Author: Alan Carvalho de Assis * Based on STME811 driver * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include "adxl345.h" #if defined(CONFIG_SENSORS_ADXL345) /**************************************************************************** * Name: adxl345_getreg8 * * Description: * Read from an 8-bit ADXL345 register * ****************************************************************************/ #ifdef CONFIG_ADXL345_I2C uint8_t adxl345_getreg8(FAR struct adxl345_dev_s *priv, uint8_t regaddr) { /* 8-bit data read sequence: * * Start - I2C_Write_Address - ADXL345_Reg_Address - * Repeated_Start - I2C_Read_Address - ADXL345_Read_Data - STOP */ struct i2c_msg_s msg[2]; uint8_t regval; int ret; /* Setup 8-bit ADXL345 address write message */ msg[0].addr = priv->config->address; /* 7-bit address */ msg[0].flags = 0; /* Write transaction, beginning with START */ msg[0].buffer = ®addr; /* Transfer from this address */ msg[0].length = 1; /* Send one byte following the address * (no STOP) */ /* Set up the 8-bit ADXL345 data read message */ msg[1].addr = priv->config->address; /* 7-bit address */ msg[1].flags = I2C_M_READ; /* Read transaction, beginning with Re-START */ msg[1].buffer = ®val; /* Transfer to this address */ msg[1].length = 1; /* Receive one byte following the address * (then STOP) */ /* Perform the transfer */ ret = I2C_TRANSFER(priv->i2c, msg, 2); if (ret < 0) { sndbg("I2C_TRANSFER failed: %d\n", ret); return 0; } #ifdef CONFIG_ADXL345_REGDEBUG dbg("%02x->%02x\n", regaddr, regval); #endif return regval; } #endif /**************************************************************************** * Name: adxl345_putreg8 * * Description: * Write a value to an 8-bit ADXL345 register * ****************************************************************************/ #ifdef CONFIG_ADXL345_I2C void adxl345_putreg8(FAR struct adxl345_dev_s *priv, uint8_t regaddr, uint8_t regval) { /* 8-bit data read sequence: * * Start - I2C_Write_Address - ADXL345_Reg_Address - ADXL345_Write_Data - STOP */ struct i2c_msg_s msg; uint8_t txbuffer[2]; int ret; #ifdef CONFIG_ADXL345_REGDEBUG dbg("%02x<-%02x\n", regaddr, regval); #endif /* Setup to the data to be transferred. Two bytes: The ADXL345 register * address followed by one byte of data. */ txbuffer[0] = regaddr; txbuffer[1] = regval; /* Setup 8-bit ADXL345 address write message */ msg.addr = priv->config->address; /* 7-bit address */ msg.flags = 0; /* Write transaction, beginning with START */ msg.buffer = txbuffer; /* Transfer from this address */ msg.length = 2; /* Send two byte following the address * (then STOP) */ /* Perform the transfer */ ret = I2C_TRANSFER(priv->i2c, &msg, 1); if (ret < 0) { sndbg("I2C_TRANSFER failed: %d\n", ret); } } #endif /**************************************************************************** * Name: adxl345_getreg16 * * Description: * Read 16-bits of data from an STMPE-11 register * ****************************************************************************/ #ifdef CONFIG_ADXL345_I2C uint16_t adxl345_getreg16(FAR struct adxl345_dev_s *priv, uint8_t regaddr) { /* 16-bit data read sequence: * * Start - I2C_Write_Address - ADXL345_Reg_Address - * Repeated_Start - I2C_Read_Address - ADXL345_Read_Data_1 - * ADXL345_Read_Data_2 - STOP */ struct i2c_msg_s msg[2]; uint8_t rxbuffer[2]; int ret; /* Setup 8-bit ADXL345 address write message */ msg[0].addr = priv->config->address; /* 7-bit address */ msg[0].flags = 0; /* Write transaction, beginning with START */ msg[0].buffer = ®addr; /* Transfer from this address */ msg[0].length = 1; /* Send one byte following the address * (no STOP) */ /* Set up the 8-bit ADXL345 data read message */ msg[1].addr = priv->config->address; /* 7-bit address */ msg[1].flags = I2C_M_READ; /* Read transaction, beginning with Re-START */ msg[1].buffer = rxbuffer; /* Transfer to this address */ msg[1].length = 2; /* Receive two bytes following the address * (then STOP) */ /* Perform the transfer */ ret = I2C_TRANSFER(priv->i2c, msg, 2); if (ret < 0) { sndbg("I2C_TRANSFER failed: %d\n", ret); return 0; } #ifdef CONFIG_ADXL345_REGDEBUG dbg("%02x->%02x%02x\n", regaddr, rxbuffer[0], rxbuffer[1]); #endif return (uint16_t)rxbuffer[0] << 8 | (uint16_t)rxbuffer[1]; } #endif #endif /* CONFIG_SENSORS_ADXL345 */