1 /*
2  * Copyright (c) 2015, Freescale Semiconductor, Inc.
3  * Copyright 2016-2017 NXP
4  * All rights reserved.
5  *
6  * SPDX-License-Identifier: BSD-3-Clause
7  */
8 
9 /*! \file driver_FXLS8962.c
10     \brief Provides init() and read() functions for the FXLS8962 3-axis accelerometer
11 */
12 
13 #include "board.h"                      // generated by Kinetis Expert.  Long term - merge sensor_board.h into this file
14 #include "sensor_fusion.h"              // Sensor fusion structures and types
15 #include "sensor_io_i2c.h"              // Required for registerreadlist_t / registerwritelist_t declarations
16 #include "sensor_drv.h"                 // Contains sensor state and error definitions
17 #include "fxls8962.h"                   // describes the FXLS8962 register definition and its bit mask
18 #include "drivers.h"                    // Device specific drivers supplied by NXP (can be replaced with user drivers)
19 #define FXLS8962_COUNTSPERG 512
20 #define FXLS8962_ACCEL_FIFO_SIZE 32
21 
22 #if F_USING_ACCEL
23 
24 // Command definition to read the WHO_AM_I value.
25 const registerreadlist_t    FXLS8962_WHO_AM_I_READ[] =
26 {
27     { .readFrom = FXLS8962_WHO_AM_I, .numBytes = 1 }, __END_READ_DATA__
28 };
29 
30 // Command definition to read the number of entries in the accel FIFO.
31 const registerreadlist_t    FXLS8962_INT_STATUS_READ[] =
32 {
33     { .readFrom = FXLS8962_INT_STATUS, .numBytes = 1 }, __END_READ_DATA__
34 };
35 
36 // Command definition to read the number of entries in the accel FIFO.
37 registerreadlist_t          FXLS8962_DATA_READ[] =
38 {
39     { .readFrom = FXLS8962_OUT_X_LSB, .numBytes = 6 }, __END_READ_DATA__
40 };
41 
42 // Each entry in a RegisterWriteList is composed of: register address, value to write, bit-mask to apply to write (0 enables)
43 const registerwritelist_t   FXLS8962_Initialization[] =
44 {
45     // write 0000 0000 = 0x00 to SENS_CONFIG1 to place FXLS8962 into standby
46     // [7-1]: Set when taking the part out of standby
47     // [0]: ACTIVE=0 for standby
48     { FXLS8962_SENS_CONFIG1, 0x00, 0x00 },
49 
50     // write 0101 0000 = 0x50 to SENS_CONFIG2 register to set High Performance Mode
51     // [7-6]: WAKE_PM=01 for High Performance Mode
52     // [5-4]: SLEEP_PM=01 for High Performance Mode
53     // [3]: LE_BE=0 for Little Endian
54     // [2]: BLOCK=0 for normal latching
55     // [1]: AINC_TEMP=0 to not include temperature in auto increment
56     // [0]: F_READ=0 for full register reads
57     { FXLS8962_SENS_CONFIG2, 0x50, 0x00 },
58 
59      // write XXXX 0000 = to SENS_CONFIG3 register to set ODR
60     // [7-4]: WAKE_ODR=1100 for 0.781Hz ODR and 4096x decimation from 3200Hz giving 0xC0
61     // [7-4]: WAKE_ODR=1011 for 1.563Hz ODR and 12048x decimation from 3200Hz giving 0xB0
62     // [7-4]: WAKE_ODR=1010 for 3.125Hz ODR and 1024x decimation from 3200Hz giving 0xA0
63     // [7-4]: WAKE_ODR=1001 for 6.25Hz ODR and 512x decimation from 3200Hz giving 0x90
64     // [7-4]: WAKE_ODR=1000 for 12.5Hz ODR and 256x decimation from 3200Hz giving 0x80
65     // [7-4]: WAKE_ODR=0111 for 25Hz ODR and 128x decimation from 3200Hz giving 0x70
66     // [7-4]: WAKE_ODR=0110 for 50Hz ODR and 64x decimation from 3200Hz giving 0x60
67     // [7-4]: WAKE_ODR=0101 for 100Hz ODR and 32x decimation from 3200Hz giving 0x50
68     // [7-4]: WAKE_ODR=0100 for 200Hz ODR and 16x decimation from 3200Hz giving 0x40
69     // [7-4]: WAKE_ODR=0011 for 400Hz ODR and 8x decimation from 3200Hz giving 0x30
70     // [7-4]: WAKE_ODR=0010 for 800Hz ODR and 4x decimation from 3200Hz giving 0x20
71     // [7-4]: WAKE_ODR=0001 for 1600Hz ODR and 2x decimation from 3200Hz giving 0x10
72     // [7-4]: WAKE_ODR=0000 for 3200Hz ODR and 1x decimation from 3200Hz giving 0x00
73     // [3-0]: SLEEP_ODR=0000
74 #if   (ACCEL_ODR_HZ <= 1) // select 0.781Hz ODR
75     	{ FXLS8962_SENS_CONFIG3, 0xC0, 0x00 },
76 #elif (ACCEL_ODR_HZ <= 2) // select 1.5625Hz ODR
77     	{ FXLS8962_SENS_CONFIG3, 0x80, 0x00 },
78 #elif (ACCEL_ODR_HZ <= 3) // select 3.125Hz ODR
79     	{ FXLS8962_SENS_CONFIG3, 0xA0, 0x00 },
80 #elif (ACCEL_ODR_HZ <= 6) // select 6.25Hz ODR
81     	{ FXLS8962_SENS_CONFIG3, 0x90, 0x00 },
82 #elif (ACCEL_ODR_HZ <= 12) // select 12.5Hz ODR
83     	{ FXLS8962_SENS_CONFIG3, 0x80, 0x00 },
84 #elif (ACCEL_ODR_HZ <= 25) // select 25Hz ODR
85     	{ FXLS8962_SENS_CONFIG3, 0x70, 0x00 },
86 #elif (ACCEL_ODR_HZ <= 50) // select 50Hz ODR
87     	{ FXLS8962_SENS_CONFIG3, 0x60, 0x00 },
88 #elif (ACCEL_ODR_HZ <= 100) // select 100Hz ODR
89     	{ FXLS8962_SENS_CONFIG3, 0x50, 0x00 },
90 #elif (ACCEL_ODR_HZ <= 200) // select 200Hz ODR
91     	{ FXLS8962_SENS_CONFIG3, 0x40, 0x00 },
92 #elif (ACCEL_ODR_HZ <= 400) // select 400Hz ODR
93     	{ FXLS8962_SENS_CONFIG3, 0x30, 0x00 },
94 #elif (ACCEL_ODR_HZ <= 800) // select 800Hz ODR
95     	{ FXLS8962_SENS_CONFIG3, 0x20, 0x00 },
96 #elif (ACCEL_ODR_HZ <= 1600) // select 1600Hz ODR
97     	{ FXLS8962_SENS_CONFIG3, 0x10, 0x00 },
98 #else  // select 3200Hz ODR
99     	{ FXLS8962_SENS_CONFIG3, 0x00, 0x00 },
100 #endif
101 
102     // write 0000 0011 = 0x03 to SENS_CONFIG1 to configure 4g mode and Active mode
103     // [7]: RST=0 for no software reset
104     // [6-5]: ST_AXIS_SEL=00 to disable self test
105     // [4]: ST_POL=0 (default)
106     // [3]: AWS_EN=0 (default)
107     // [2-1]: FSR=01 for 4g mode
108     // [1]: ACTIVE=1 for standby
109     { FXLS8962_SENS_CONFIG1, 0x03, 0x00 },
110     __END_WRITE_DATA__
111 };
112 
113 // All sensor drivers and initialization functions have the same prototype.
114 // sfg is a pointer to the master "global" sensor fusion structure.
115 // sensor = pointer to linked list element used by the sensor fusion subsystem to specify required sensors
116 
117 // sfg = pointer to top level (generally global) data structure for sensor fusion
FXLS8962_Init(struct PhysicalSensor * sensor,SensorFusionGlobals * sfg)118 int8_t FXLS8962_Init(struct PhysicalSensor *sensor, SensorFusionGlobals *sfg)
119 {
120     int32_t status;
121     uint8_t reg;
122     status = Register_I2C_Read(sensor->bus_driver, &sensor->deviceInfo, sensor->addr, FXLS8962_WHO_AM_I, 1, &reg);
123     if (status==SENSOR_ERROR_NONE) {
124         if (reg==FXLS8962_WHOAMI_VALUE) {
125             sfg->Accel.iWhoAmI = reg;
126         } else {
127             return(SENSOR_ERROR_INIT);
128         }
129       } else {
130         return(status);
131     }
132 
133     // Configure and start the FXLS8962 sensor.  This does multiple register writes
134     // (see FXLS8962_Initialization definition above)
135     status = Sensor_I2C_Write(sensor->bus_driver, &sensor->deviceInfo, sensor->addr, FXLS8962_Initialization );
136 
137     // Stash some needed constants in the SF data structure for this sensor
138     sfg->Accel.iCountsPerg = FXLS8962_COUNTSPERG;
139     sfg->Accel.fgPerCount = 1.0F / FXLS8962_COUNTSPERG;
140     sfg->Accel.fgPerCount = 1.0F / FXLS8962_COUNTSPERG;
141 
142     sensor->isInitialized = F_USING_ACCEL;
143     sfg->Accel.isEnabled = true;
144 
145     return (status);
146 }
147 
FXLS8962_Read(struct PhysicalSensor * sensor,SensorFusionGlobals * sfg)148 int8_t FXLS8962_Read(struct PhysicalSensor *sensor, SensorFusionGlobals *sfg)
149 {
150     uint8_t                     I2C_Buffer[6 * FXLS8962_ACCEL_FIFO_SIZE];    // I2C read buffer
151     int8_t                      status;         // I2C transaction status
152     uint8_t                     sensor_data_ready = 0;
153     int16_t                     sample[3];
154 
155     if(sensor->isInitialized != F_USING_ACCEL)
156     {
157         return SENSOR_ERROR_INIT;
158     }
159 
160     // read the FXLS8962_BUF_STATUS register (mapped to STATUS) and extract number of measurements available (lower 6 bits)
161     status =  Sensor_I2C_Read(sensor->bus_driver, &sensor->deviceInfo, sensor->addr, FXLS8962_INT_STATUS_READ, I2C_Buffer );
162     if (status==SENSOR_ERROR_NONE) {
163         sensor_data_ready = I2C_Buffer[0] & 0x80;
164         // return if there are no measurements in the sensor FIFO.
165         // this will only occur when the FAST_LOOP_HZ equals or exceeds ACCEL_ODR_HZ
166         if  (sensor_data_ready == 0) return status;
167     } else {
168         return(status);
169     }
170 
171     status =  Sensor_I2C_Read(sensor->bus_driver, &sensor->deviceInfo, sensor->addr, FXLS8962_DATA_READ, I2C_Buffer );
172 
173     if (status==SENSOR_ERROR_NONE) {
174          // place the 6 bytes read into the 16 bit accelerometer structure
175          sample[CHX] = (I2C_Buffer[1] << 8) | I2C_Buffer[0];
176          sample[CHY] = (I2C_Buffer[3] << 8) | I2C_Buffer[2];
177          sample[CHZ] = (I2C_Buffer[5] << 8) | I2C_Buffer[4];
178          conditionSample(sample);  // truncate negative values to -32767
179          addToFifo((union FifoSensor*) &(sfg->Accel), ACCEL_FIFO_SIZE, sample);
180     }
181 
182     return (status);
183 }
184 
185 
186 // Each entry in a RegisterWriteList is composed of: register address, value to write, bit-mask to apply to write (0 enables)
187 const registerwritelist_t   FXLS8962_IDLE[] =
188 {
189   // Set ACTIVE = other bits unchanged
190   { FXLS8962_SENS_CONFIG1, 0x00, 0x01 },
191     __END_WRITE_DATA__
192 };
193 
194 // FXLS8962_Idle places the sensor into Standby mode (see datasheet for wakeup time)
FXLS8962_Idle(struct PhysicalSensor * sensor,SensorFusionGlobals * sfg)195 int8_t FXLS8962_Idle(struct PhysicalSensor *sensor, SensorFusionGlobals *sfg)
196 {
197     int32_t     status;
198     if(sensor->isInitialized == F_USING_ACCEL) {
199         status = Sensor_I2C_Write(sensor->bus_driver, &sensor->deviceInfo, sensor->addr, FXLS8962_IDLE );
200         sensor->isInitialized = 0;
201         sfg->Accel.isEnabled = false;
202     } else {
203       return SENSOR_ERROR_INIT;
204     }
205     return status;
206 }
207 #endif // if F_USING_ACCEL
208