/****************************************************************************
* drivers/sensors/as5048b.c
* Character driver for the AMS AS5048B Magnetic Rotary Encoder
*
* Copyright (C) 2015 Omni Hoverboards Inc. All rights reserved.
* Author: Paul Alexander Patience <paul-a.patience@polymtl.ca>
*
* Copyright (C) 2016 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <nuttx/config.h>
#include <errno.h>
#include <debug.h>
#include <stdlib.h>
#include <nuttx/kmalloc.h>
#include <nuttx/fs/fs.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/sensors/as5048b.h>
#if defined(CONFIG_I2C) && defined(CONFIG_QENCODER) && defined(CONFIG_AS5048B)
/****************************************************************************
* Private Types
****************************************************************************/
struct as5048b_dev_s
{
struct qe_lowerhalf_s lower; /* AS5048B quadrature encoder lower half */
FAR struct i2c_master_s *i2c; /* I2C interface */
uint8_t addr; /* I2C address */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* I2C Helpers */
static int as5048b_readu8(FAR struct as5048b_dev_s *priv, uint8_t regaddr,
FAR uint8_t *regval);
static int as5048b_readu16(FAR struct as5048b_dev_s *priv, uint8_t regaddrhi,
uint8_t regaddrlo, FAR uint16_t *regval);
static int as5048b_writeu8(FAR struct as5048b_dev_s *priv, uint8_t regaddr,
uint8_t regval);
static int as5048b_writeu16(FAR struct as5048b_dev_s *priv, uint8_t regaddrhi,
uint8_t regaddrlo, uint16_t regval);
static int as5048b_readzero(FAR struct as5048b_dev_s *priv,
FAR uint16_t *zero);
static int as5048b_writezero(FAR struct as5048b_dev_s *priv, uint16_t zero);
static int as5048b_readagc(FAR struct as5048b_dev_s *priv, FAR uint8_t *agc);
static int as5048b_readdiag(FAR struct as5048b_dev_s *priv,
FAR uint8_t *diag);
static int as5048b_readmag(FAR struct as5048b_dev_s *priv, FAR uint16_t *mag);
static int as5048b_readang(FAR struct as5048b_dev_s *priv, FAR uint16_t *ang);
/* Character Driver Methods */
static int as5048b_setup(FAR struct qe_lowerhalf_s *lower);
static int as5048b_shutdown(FAR struct qe_lowerhalf_s *lower);
static int as5048b_position(FAR struct qe_lowerhalf_s *lower,
FAR int32_t *pos);
static int as5048b_reset(FAR struct qe_lowerhalf_s *lower);
static int as5048b_ioctl(FAR struct qe_lowerhalf_s *lower, int cmd,
unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct qe_ops_s g_qeops =
{
as5048b_setup,
as5048b_shutdown,
as5048b_position,
as5048b_reset,
as5048b_ioctl
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: as5048b_readu8
*
* Description:
* Read from an 8-bit register
*
****************************************************************************/
static int as5048b_readu8(FAR struct as5048b_dev_s *priv, uint8_t regaddr,
FAR uint8_t *regval)
{
int ret;
struct i2c_config_s config;
/* Set up the I2C configuration */
config.frequency = priv->frequency;
config.address = priv->addr;
config.addrlen = 7;
/* Write the register address */
ret = i2c_write(priv->i2c, &config, ®addr, sizeof(regaddr));
if (ret < 0)
{
snerr("ERROR: i2c_write failed: %d\n", ret);
return ret;
}
/* Restart and read 8 bits from the register */
ret = i2c_read(priv->i2c, &config, regval, sizeof(*regval));
if (ret < 0)
{
snerr("ERROR: i2c_read failed: %d\n", ret);
return ret;
}
sninfo("addr: %02x value: %02x ret: %d\n", regaddr, *regval, ret);
return ret;
}
/****************************************************************************
* Name: as5048b_readu16
*
* Description:
* Read from two 8-bit registers
*
****************************************************************************/
static int as5048b_readu16(FAR struct as5048b_dev_s *priv, uint8_t regaddrhi,
uint8_t regaddrlo, FAR uint16_t *regval)
{
uint8_t hi, lo;
int ret;
/* Read the high 8 bits of the 13-bit value */
ret = as5048b_readu8(priv, regaddrhi, &hi);
if (ret < 0)
{
snerr("ERROR: as5048b_readu8 failed: %d\n", ret);
return ret;
}
/* Read the low 5 bits of the 13-bit value */
ret = as5048b_readu8(priv, regaddrlo, &lo);
if (ret < 0)
{
snerr("ERROR: as5048b_readu8 failed: %d\n", ret);
return ret;
}
*regval = (uint16_t)hi << 6 | (uint16_t)lo;
sninfo("addrhi: %02x addrlo: %02x value: %04x ret: %d\n",
regaddrhi, regaddrlo, *regval, ret);
return ret;
}
/****************************************************************************
* Name: as5048b_writeu8
*
* Description:
* Write from an 8-bit register
*
****************************************************************************/
static int as5048b_writeu8(FAR struct as5048b_dev_s *priv, uint8_t regaddr,
uint8_t regval)
{
struct i2c_config_s config;
uint8_t buffer[2];
int ret;
sninfo("addr: %02x value: %02x\n", regaddr, regval);
/* Set up the I2C configuration */
config.frequency = priv->frequency;
config.address = priv->addr;
config.addrlen = 7;
/* Set up a 2-byte message to send */
buffer[0] = regaddr;
buffer[1] = regval;
/* Write the register address followed by the data (no RESTART) */
ret = i2c_write(priv->i2c, &config, buffer, sizeof(buffer));
if (ret < 0)
{
snerr("ERROR: i2c_write failed: %d\n", ret);
}
return ret;
}
/****************************************************************************
* Name: as5048b_writeu16
*
* Description:
* Write to two 8-bit registers
*
****************************************************************************/
static int as5048b_writeu16(FAR struct as5048b_dev_s *priv, uint8_t regaddrhi,
uint8_t regaddrlo, uint16_t regval)
{
int ret;
sninfo("addrhi: %02x addrlo: %02x value: %04x\n",
regaddrhi, regaddrlo, regval);
/* Write the high 8 bits of the 13-bit value */
ret = as5048b_writeu8(priv, regaddrhi, (uint8_t)(regval >> 6));
if (ret < 0)
{
snerr("ERROR: as5048b_writeu8 failed: %d\n", ret);
return ret;
}
/* Write the low 5 bits of the 13-bit value */
ret = as5048b_writeu8(priv, regaddrhi, (uint8_t)regval);
if (ret < 0)
{
snerr("ERROR: as5048b_writeu8 failed: %d\n", ret);
}
return ret;
}
/****************************************************************************
* Name: as5048b_readzero
*
* Description:
* Read from the zero position registers
*
****************************************************************************/
static int as5048b_readzero(FAR struct as5048b_dev_s *priv,
FAR uint16_t *zero)
{
int ret;
ret = as5048b_readu16(priv, AS5048B_ZEROHI_REG, AS5048B_ZEROLO_REG, zero);
if (ret < 0)
{
snerr("ERROR: as5048b_readu16 failed: %d\n", ret);
return ret;
}
sninfo("zero: %04x ret: %d\n", *zero, ret);
return ret;
}
/****************************************************************************
* Name: as5048b_writezero
*
* Description:
* Write to the zero position registers
*
****************************************************************************/
static int as5048b_writezero(FAR struct as5048b_dev_s *priv, uint16_t zero)
{
int ret;
sninfo("zero: %04x\n", zero);
ret = as5048b_writeu16(priv, AS5048B_ZEROHI_REG, AS5048B_ZEROLO_REG, zero);
if (ret < 0)
{
snerr("ERROR: as5048b_writeu16 failed: %d\n", ret);
}
return ret;
}
/****************************************************************************
* Name: as5048b_readagc
*
* Description:
* Read from the automatic gain control register
*
****************************************************************************/
static int as5048b_readagc(FAR struct as5048b_dev_s *priv, FAR uint8_t *agc)
{
int ret;
ret = as5048b_readu8(priv, AS5048B_AGC_REG, agc);
if (ret < 0)
{
snerr("ERROR: as5048b_readu8 failed: %d\n", ret);
return ret;
}
sninfo("agc: %02x ret: %d\n", *agc, ret);
return ret;
}
/****************************************************************************
* Name: as5048b_readdiag
*
* Description:
* Read from the diagnostics register
*
****************************************************************************/
static int as5048b_readdiag(FAR struct as5048b_dev_s *priv, FAR uint8_t *diag)
{
int ret;
ret = as5048b_readu8(priv, AS5048B_DIAG_REG, diag);
if (ret < 0)
{
snerr("ERROR: as5048b_readu8 failed: %d\n", ret);
return ret;
}
sninfo("diag: %02x ret: %d\n", *diag, ret);
return ret;
}
/****************************************************************************
* Name: as5048b_readmag
*
* Description:
* Read from the magnitude registers
*
****************************************************************************/
static int as5048b_readmag(FAR struct as5048b_dev_s *priv, FAR uint16_t *mag)
{
int ret;
ret = as5048b_readu16(priv, AS5048B_MAGHI_REG, AS5048B_MAGLO_REG, mag);
if (ret < 0)
{
snerr("ERROR: as5048b_readu16 failed: %d\n", ret);
return ret;
}
sninfo("mag: %04x ret: %d\n", *mag, ret);
return ret;
}
/****************************************************************************
* Name: as5048b_readang
*
* Description:
* Read from the angle registers
*
****************************************************************************/
static int as5048b_readang(FAR struct as5048b_dev_s *priv, FAR uint16_t *ang)
{
int ret;
ret = as5048b_readu16(priv, AS5048B_ANGHI_REG, AS5048B_ANGLO_REG, ang);
if (ret < 0)
{
snerr("ERROR: as5048b_readu16 failed: %d\n", ret);
return ret;
}
sninfo("ang: %04x ret: %d\n", *ang, ret);
return ret;
}
/****************************************************************************
* Name: as5048b_setup
*
* Description:
* This method is called when the driver is opened
*
****************************************************************************/
static int as5048b_setup(FAR struct qe_lowerhalf_s *lower)
{
return OK;
}
/****************************************************************************
* Name: as5048b_shutdown
*
* Description:
* This method is called when the driver is closed
*
****************************************************************************/
static int as5048b_shutdown(FAR struct qe_lowerhalf_s *lower)
{
return OK;
}
/****************************************************************************
* Name: as5048b_position
*
* Description:
* Return the current position measurement
*
****************************************************************************/
static int as5048b_position(FAR struct qe_lowerhalf_s *lower,
FAR int32_t *pos)
{
FAR struct as5048b_dev_s *priv = (FAR struct as5048b_dev_s *)lower;
uint16_t ang;
int ret;
ret = as5048b_readang(priv, &ang);
if (ret < 0)
{
snerr("ERROR: as5048b_readang failed: %d\n", ret);
return ret;
}
*pos = (int32_t)ang;
return ret;
}
/****************************************************************************
* Name: as5048b_reset
*
* Description:
* Reset the position measurement to zero
*
****************************************************************************/
static int as5048b_reset(FAR struct qe_lowerhalf_s *lower)
{
FAR struct as5048b_dev_s *priv = (FAR struct as5048b_dev_s *)lower;
uint16_t ang;
int ret;
ret = as5048b_writezero(priv, 0);
if (ret < 0)
{
snerr("ERROR: as5048b_writezero failed: %d\n", ret);
return ret;
}
ret = as5048b_readang(priv, &ang);
if (ret < 0)
{
snerr("ERROR: as5048b_readang failed: %d\n", ret);
return ret;
}
ret = as5048b_writezero(priv, ang);
if (ret < 0)
{
snerr("ERROR: as5048b_writezero failed: %d\n", ret);
}
return ret;
}
/****************************************************************************
* Name: as5048b_ioctl
****************************************************************************/
static int as5048b_ioctl(FAR struct qe_lowerhalf_s *lower, int cmd,
unsigned long arg)
{
FAR struct as5048b_dev_s *priv = (FAR struct as5048b_dev_s *)lower;
int ret = OK;
switch (cmd)
{
/* Read from the zero position registers. Arg: int32_t* pointer. */
case QEIOC_ZEROPOSITION:
{
FAR int32_t *ptr = (FAR int32_t *)((uintptr_t)arg);
uint16_t zero;
DEBUGASSERT(ptr != NULL);
ret = as5048b_readzero(priv, &zero);
if (ret == OK)
{
*ptr = (int32_t)zero;
}
sninfo("zero: %04x ret: %d\n", *ptr, ret);
}
break;
/* Read from the automatic gain control register. Arg: uint8_t* pointer. */
case QEIOC_AUTOGAINCTL:
{
FAR uint8_t *ptr = (FAR uint8_t *)((uintptr_t)arg);
DEBUGASSERT(ptr != NULL);
ret = as5048b_readagc(priv, ptr);
sninfo("agc: %02x ret: %d\n", *ptr, ret);
}
break;
/* Read from the diagnostics register. Arg: uint8_t* pointer. */
case QEIOC_DIAGNOSTICS:
{
FAR uint8_t *ptr = (FAR uint8_t *)((uintptr_t)arg);
DEBUGASSERT(ptr != NULL);
ret = as5048b_readdiag(priv, ptr);
sninfo("diag: %02x ret: %d\n", *ptr, ret);
}
break;
/* Read from the magnitude registers. Arg: int32_t* pointer. */
case QEIOC_MAGNITUDE:
{
FAR int32_t *ptr = (FAR int32_t *)((uintptr_t)arg);
uint16_t mag;
DEBUGASSERT(ptr != NULL);
ret = as5048b_readmag(priv, &mag);
if (ret == OK)
{
*ptr = (int32_t)mag;
}
sninfo("mag: %04x ret: %d\n", *ptr, ret);
}
break;
default:
snerr("ERROR: Unrecognized cmd: %d arg: %ld\n", cmd, arg);
ret = -ENOTTY;
break;
}
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: as5048b_initialize
*
* Description:
* Initialize the AS5048B device.
*
* Input Parameters:
* i2c - An I2C driver instance.
* addr - The I2C address of the AS5048B.
*
* Returned Value:
* A new lower half quadrature encoder interface for the AS5048B on success;
* NULL on failure.
*
****************************************************************************/
FAR struct qe_lowerhalf_s *as5048b_initialize(FAR struct i2c_master_s *i2c,
uint8_t addr)
{
FAR struct as5048b_dev_s *priv;
DEBUGASSERT(i2c != NULL);
/* Initialize the device's structure */
priv = (FAR struct as5048b_dev_s *)kmm_malloc(sizeof(*priv));
if (priv == NULL)
{
snerr("ERROR: Failed to allocate instance\n");
return NULL;
}
priv->lower.ops = &g_qeops;
priv->i2c = i2c;
priv->addr = addr;
return &priv->lower;
}
#endif /* CONFIG_I2C && CONFIG_QENCODER && CONFIG_AS5048B */