/****************************************************************************
* arch/drivers/analog/ads1255.c
*
* Copyright (C) 2010, 2016 Gregory Nutt. All rights reserved.
* Copyright (C) 2011 Li Zhuoyi. All rights reserved.
* Author: Li Zhuoyi <lzyy.cn@gmail.com>
* Gregory Nutt <gnutt@nuttx.org>
*
* This file is a part of NuttX:
*
* Copyright (C) 2010 Gregory Nutt. All rights reserved.
*
* 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 <stdio.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <semaphore.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <nuttx/wqueue.h>
#include <nuttx/spi/spi.h>
#include <nuttx/analog/adc.h>
#if defined(CONFIG_ADC_ADS1255)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define ADS125X_BUFON 0x02
#define ADS125X_BUFOFF 0x00
#define ADS125X_PGA1 0x00
#define ADS125X_PGA2 0x01
#define ADS125X_PGA4 0x02
#define ADS125X_PGA8 0x03
#define ADS125X_PGA16 0x04
#define ADS125X_PGA32 0x05
#define ADS125X_PGA64 0x06
#define ADS125X_RDATA 0x01 /* Read Data */
#define ADS125X_RDATAC 0x03 /* Read Data Continuously */
#define ADS125X_SDATAC 0x0F /* Stop Read Data Continuously */
#define ADS125X_RREG 0x10 /* Read from REG */
#define ADS125X_WREG 0x50 /* Write to REG */
#define ADS125X_SELFCAL 0xF0 /* Offset and Gain Self-Calibration */
#define ADS125X_SELFOCAL 0xF1 /* Offset Self-Calibration */
#define ADS125X_SELFGCAL 0xF2 /* Gain Self-Calibration */
#define ADS125X_SYSOCAL 0xF3 /* System Offset Calibration */
#define ADS125X_SYSGCAL 0xF4 /* System Gain Calibration */
#define ADS125X_SYNC 0xFC /* Synchronize the A/D Conversion */
#define ADS125X_STANDBY 0xFD /* Begin Standby Mode */
#define ADS125X_RESET 0xFE /* Reset to Power-Up Values */
#define ADS125X_WAKEUP 0xFF /* Completes SYNC and Exits Standby Mode */
#ifndef CONFIG_ADS1255_FREQUENCY
# define CONFIG_ADS1255_FREQUENCY 1000000
#endif
#ifndef CONFIG_ADS1255_MUX
# define CONFIG_ADS1255_MUX 0x01
#endif
#ifndef CONFIG_ADS1255_CHMODE
# define CONFIG_ADS1255_CHMODE 0x00
#endif
#ifndef CONFIG_ADS1255_BUFON
# define CONFIG_ADS1255_BUFON 1
#endif
#ifndef CONFIG_ADS1255_PGA
# define CONFIG_ADS1255_PGA ADS125X_PGA2
#endif
#ifndef CONFIG_ADS1255_SPS
# define CONFIG_ADS1255_SPS 50
#endif
/****************************************************************************
* Private Types
****************************************************************************/
struct ads1255_dev_s
{
FAR const struct adc_callback_s *cb;
FAR struct spi_dev_s *spi; /* Cached SPI device reference */
struct work_s work;
uint8_t channel;
uint32_t sps;
uint8_t pga;
uint8_t buf;
const uint8_t *mux;
int irq;
int devno;
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static void adc_lock(FAR struct spi_dev_s *spi);
static void adc_unlock(FAR struct spi_dev_s *spi);
/* ADC methods */
static int adc_bind(FAR struct adc_dev_s *dev,
FAR const struct adc_callback_s *callback);
static void adc_reset(FAR struct adc_dev_s *dev);
static int adc_setup(FAR struct adc_dev_s *dev);
static void adc_shutdown(FAR struct adc_dev_s *dev);
static void adc_rxint(FAR struct adc_dev_s *dev, bool enable);
static int adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg);
/* Interrupt handling */
static void adc_worker(FAR void *arg);
static int adc_interrupt(int irq, void *context, FAR void *arg);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct adc_ops_s g_adcops =
{
.ao_bind = adc_bind, /* ao_bind */
.ao_reset = adc_reset, /* ao_reset */
.ao_setup = adc_setup, /* ao_setup */
.ao_shutdown = adc_shutdown, /* ao_shutdown */
.ao_rxint = adc_rxint, /* ao_rxint */
.ao_ioctl = adc_ioctl /* ao_read */
};
static struct ads1255_dev_s g_adcpriv =
{
.mux = (const uint8_t [])
{
CONFIG_ADS1255_MUX, 0
},
.sps = CONFIG_ADS1255_SPS,
.channel = 0,
.irq = CONFIG_ADS1255_IRQ,
};
static struct adc_dev_s g_adcdev =
{
.ad_ops = &g_adcops,
.ad_priv = &g_adcpriv,
};
/****************************************************************************
* Private Functions
****************************************************************************/
static uint8_t getspsreg(uint16_t sps)
{
static const unsigned short sps_tab[] =
{
3, 7, 12, 20, 27, 40, 55, 80,
300, 750, 1500, 3000, 5000, 10000, 20000, 65535,
};
static const unsigned char sps_reg[] =
{
0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x72,
0x82, 0x92, 0xa1, 0xb0, 0xc0, 0xd0, 0xe0, 0xf0,
};
int i;
for (i = 0; i < 16; i++)
{
if (sps < sps_tab[i])
{
return sps_reg[i];
}
}
return sps_reg[15];
}
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: adc_lock
*
* Description:
* Lock and configure the SPI bus.
*
****************************************************************************/
static void adc_lock(FAR struct spi_dev_s *spi)
{
(void)SPI_LOCK(spi, true);
SPI_SETMODE(spi, SPIDEV_MODE1);
SPI_SETBITS(spi, 8);
(void)SPI_HWFEATURES(spi, 0);
SPI_SETFREQUENCY(spi, CONFIG_ADS1255_FREQUENCY);
}
/****************************************************************************
* Name: adc_unlock
*
* Description:
* Unlock the SPI bus.
*
****************************************************************************/
static void adc_unlock(FAR struct spi_dev_s *spi)
{
(void)SPI_LOCK(spi, false);
}
/****************************************************************************
* Name: adc_bind
*
* Description:
* Bind the upper-half driver callbacks to the lower-half implementation. This
* must be called early in order to receive ADC event notifications.
*
****************************************************************************/
static int adc_bind(FAR struct adc_dev_s *dev,
FAR const struct adc_callback_s *callback)
{
FAR struct ads1255_dev_s *priv = (FAR struct ads1255_dev_s *)dev->ad_priv;
DEBUGASSERT(priv != NULL);
priv->cb = callback;
return OK;
}
/****************************************************************************
* Name: adc_reset
*
* Description:
* Reset the ADC device. Called early to initialize the hardware. This
* is called, before ao_setup() and on error conditions.
*
****************************************************************************/
static void adc_reset(FAR struct adc_dev_s *dev)
{
FAR struct ads1255_dev_s *priv = (FAR struct ads1255_dev_s *)dev->ad_priv;
FAR struct spi_dev_s *spi;
DEBUGASSERT(priv != NULL && priv->spi != NULL);
spi = priv->spi;
adc_lock(spi);
usleep(1000);
SPI_SELECT(spi, priv->devno, true);
SPI_SEND(spi, ADS125X_WREG + 0x03); /* WRITE SPS REG */
SPI_SEND(spi, 0x00); /* count=1 */
SPI_SEND(spi, 0x63);
SPI_SELECT(spi, priv->devno, false);
adc_unlock(spi);
}
/****************************************************************************
* Name: adc_setup
*
* Description:
* Configure the ADC. This method is called the first time that the ADC
* device is opened. This will occur when the port is first opened.
* This setup includes configuring and attaching ADC interrupts. Interrupts
* are all disabled upon return.
*
****************************************************************************/
static int adc_setup(FAR struct adc_dev_s *dev)
{
FAR struct ads1255_dev_s *priv = (FAR struct ads1255_dev_s *)dev->ad_priv;
FAR struct spi_dev_s *spi;
int ret;
DEBUGASSERT(priv != NULL && priv->spi != NULL);
spi = priv->spi;
ret = irq_attach(priv->irq, adc_interrupt, NULL);
if (ret == OK)
{
adc_lock(spi);
SPI_SELECT(spi, priv->devno, true);
SPI_SEND(spi, ADS125X_WREG); /* WRITE REG from 0 */
SPI_SEND(spi, 0x03); /* count=4+1 */
if (priv->buf)
{
SPI_SEND(spi, ADS125X_BUFON); /* REG0 STATUS BUFFER ON */
}
else
{
SPI_SEND(spi, ADS125X_BUFOFF);
}
SPI_SEND(spi, priv->mux[0]);
SPI_SEND(spi, priv->pga); /* REG2 ADCON PGA=2 */
SPI_SEND(spi, getspsreg(priv->sps));
usleep(1000);
SPI_SEND(spi, ADS125X_SELFCAL);
SPI_SELECT(spi, priv->devno, false);
adc_unlock(spi);
up_enable_irq(priv->irq);
}
return ret;
}
/****************************************************************************
* Name: adc_shutdown
*
* Description:
* Disable the ADC. This method is called when the ADC device is closed.
* This method reverses the operation the setup method.
*
****************************************************************************/
static void adc_shutdown(FAR struct adc_dev_s *dev)
{
FAR struct ads1255_dev_s *priv = (FAR struct ads1255_dev_s *)dev->ad_priv;
DEBUGASSERT(priv != NULL);
up_disable_irq(priv->irq);
irq_detach(priv->irq);
}
/****************************************************************************
* Name: adc_rxint
*
* Description:
* Call to enable or disable RX interrupts
*
****************************************************************************/
static void adc_rxint(FAR struct adc_dev_s *dev, bool enable)
{
FAR struct ads1255_dev_s *priv = (FAR struct ads1255_dev_s *)dev->ad_priv;
DEBUGASSERT(priv != NULL);
if (enable)
{
up_enable_irq(priv->irq);
}
else
{
up_disable_irq(priv->irq);
}
}
/****************************************************************************
* Name: adc_ioctl
*
* Description:
* All ioctl calls will be routed through this method
*
****************************************************************************/
static int adc_ioctl(FAR struct adc_dev_s *dev, int cmd, unsigned long arg)
{
_err("ERROR: Fix me; Not Implemented\n");
return 0;
}
/****************************************************************************
* Name: adc_worker
*
* Description:
* ADC interrupt work
*
****************************************************************************/
static void adc_worker(FAR void *arg)
{
FAR struct ads1255_dev_s *priv = (FAR struct ads1255_dev_s *)arg;
FAR struct spi_dev_s *spi;
unsigned char buf[4];
unsigned char ch;
DEBUGASSERT(priv != NULL && priv->spi != NULL);
spi = priv->spi;
/* REVISIT: Cannot perform SPI operations from an interrupt handler!
* Need to use the high priority work queue.
*/
adc_lock(spi);
SPI_SELECT(spi, priv->devno, true);
SPI_SEND(spi, ADS125X_RDATA);
up_udelay(10);
buf[3] = SPI_SEND(spi, 0xff);
buf[2] = SPI_SEND(spi, 0xff);
buf[1] = SPI_SEND(spi, 0xff);
buf[0] = 0;
priv->channel++;
ch = priv->mux[priv->channel];
if (ch == 0)
{
priv->channel = 0;
ch = priv->mux[0];
}
SPI_SEND(spi, ADS125X_WREG + 0x01);
SPI_SEND(spi, 0x00);
SPI_SEND(spi, ch);
SPI_SEND(spi, ADS125X_SYNC);
up_udelay(2);
SPI_SEND(spi, ADS125X_WAKEUP);
SPI_SELECT(spi, priv->devno, false);
adc_unlock(spi);
/* Verify that the upper-half driver has bound its callback functions */
if (priv->cb != NULL)
{
/* Perform the data received callback */
DEBUGASSERT(priv->cb->au_receive != NULL);
priv->cb->au_receive(&g_adcdev, priv->channel, *(int32_t *)buf);
}
/* Re-enable ADC interrupts */
up_enable_irq(priv->irq);
}
/****************************************************************************
* Name: adc_interrupt
*
* Description:
* ADC interrupt handler
*
****************************************************************************/
static int adc_interrupt(int irq, void *context, FAR void *arg)
{
FAR struct ads1255_dev_s *priv = (FAR struct ads1255_dev_s *)g_adcdev.ad_priv;
DEBUGASSERT(priv != NULL);
/* Disable further ADC interrupts until the worker thread has executed. */
up_disable_irq(priv->irq);
/* Schedule the ADC work for the worker thread. Whent he sample has been
* processed, the ADC interrupt will be re-enabled.
*/
DEBUGVERIFY(work_queue(HPWORK, &priv->work, adc_worker, priv, 0));
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_ads1255initialize
*
* Description:
* Initialize the selected adc port
*
* Input Parameter:
* Port number (for hardware that has multiple adc interfaces)
*
* Returned Value:
* Valid can device structure reference on success; a NULL on failure
*
****************************************************************************/
FAR struct adc_dev_s *up_ads1255initialize(FAR struct spi_dev_s *spi,
unsigned int devno)
{
FAR struct ads1255_dev_s *priv = (FAR struct ads1255_dev_s *)g_adcdev.ad_priv;
DEBUGASSERT(spi != NULL);
/* Driver state data */
priv->cb = NULL;
priv->spi = spi;
priv->devno = devno;
return &g_adcdev;
}
#endif