Add driver for the Feescale MPL115A baramoter. From Alan Carvalho de Assis

2 files changed, 516 insertions, 0 deletions

diff --git a/nuttx/drivers/sensors/mpl115a.c b/nuttx/drivers/sensors/mpl115a.c
new file mode 100644
index 000000000..b507b3343
--- /dev/null
+++ b/nuttx/drivers/sensors/mpl115a.c
@@ -0,0 +1,396 @@
+/****************************************************************************
+ * drivers/sensors/mpl115a.c
+ * Character driver for the Freescale MPL115A1 Barometer Sensor
+ *
+ *   Copyright (C) 2011, 2013 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 <stdlib.h>
+#include <fixedmath.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/fs/fs.h>
+#include <nuttx/spi/spi.h>
+#include <nuttx/sensors/mpl115a.h>
+
+#if defined(CONFIG_SPI) && defined(CONFIG_MPL115A)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private
+ ****************************************************************************/
+
+struct mpl115a_dev_s
+{
+  FAR struct spi_dev_s *spi; /* SPI interface */
+  int16_t mpl115a_cal_a0;
+  int16_t mpl115a_cal_b1;
+  int16_t mpl115a_cal_b2;
+  int16_t mpl115a_cal_c12;
+  uint16_t mpl115a_temperature;
+  uint16_t mpl115a_pressure;
+};
+
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static inline void mpl115a_configspi(FAR struct spi_dev_s *spi);
+static uint8_t mpl115a_getreg8(FAR struct mpl115a_dev_s *priv, uint8_t regaddr);
+static void mpl115a_updatecaldata(FAR struct mpl115a_dev_s *priv);
+static void mpl115a_read_press_temp(FAR struct mpl115a_dev_s *priv);
+static int mpl115a_getpressure(FAR struct mpl115a_dev_s *priv);
+
+/* Character driver methods */
+
+static int     mpl115a_open(FAR struct file *filep);
+static int     mpl115a_close(FAR struct file *filep);
+static ssize_t mpl115a_read(FAR struct file *, FAR char *, size_t);
+static ssize_t mpl115a_write(FAR struct file *filep, FAR const char *buffer, size_t buflen);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static const struct file_operations g_mpl115afops =
+{
+  mpl115a_open,
+  mpl115a_close,
+  mpl115a_read,
+  mpl115a_write,
+  0,
+  0
+#ifndef CONFIG_DISABLE_POLL
+  , 0
+#endif
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+#ifndef CONFIG_SPI_OWNBUS
+static inline void mpl115a_configspi(FAR struct spi_dev_s *spi)
+{
+  /* Configure SPI for the MPL115A */
+
+  SPI_SETMODE(spi, SPIDEV_MODE0);
+  SPI_SETBITS(spi, 8);
+  SPI_SETFREQUENCY(spi, MPL115A_SPI_MAXFREQUENCY);
+}
+#endif
+
+/****************************************************************************
+ * Name: mpl115a_getreg8
+ *
+ * Description:
+ *   Read from an 8-bit MPL115A register
+ *
+ ****************************************************************************/
+
+static uint8_t mpl115a_getreg8(FAR struct mpl115a_dev_s *priv, uint8_t regaddr)
+{
+  uint8_t regval;
+
+  /* If SPI bus is shared then lock and configure it */
+
+#ifndef CONFIG_SPI_OWNBUS
+  (void)SPI_LOCK(priv->spi, true);
+  mpl115a_configspi(priv->spi);
+#endif
+
+  /* Select the MPL115A */
+
+  SPI_SELECT(priv->spi, SPIDEV_BAROMETER, true);
+
+  /* Send register to read and get the next byte */
+
+  (void)SPI_SEND(priv->spi, regaddr);
+  SPI_RECVBLOCK(priv->spi, &regval, 1);
+
+  /* Deselect the MPL115A */
+
+  SPI_SELECT(priv->spi, SPIDEV_BAROMETER, false);
+
+  /* Unlock bus */
+
+#ifndef CONFIG_SPI_OWNBUS
+  (void)SPI_LOCK(priv->spi, false);
+#endif
+
+#ifdef CONFIG_MPL115A_REGDEBUG
+  dbg("%02x->%02x\n", regaddr, regval);
+#endif
+  return regval;
+}
+
+/****************************************************************************
+ * Name: mpl115a_updatecaldata
+ *
+ * Description:
+ *   Update Calibration Coefficient Data
+ *
+ ****************************************************************************/
+
+static void mpl115a_updatecaldata(FAR struct mpl115a_dev_s *priv)
+{
+  /* Get a0 coefficient */
+  priv->mpl115a_cal_a0 = mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_A0_MSB << 1)) << 8;
+  priv->mpl115a_cal_a0 |= mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_A0_LSB << 1));
+  sndbg("a0 = %d\n", priv->mpl115a_cal_a0);
+
+  /* Get b1 coefficient */
+  priv->mpl115a_cal_b1 = mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_B1_MSB << 1)) << 8;
+  priv->mpl115a_cal_b1 |= mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_B1_LSB << 1));
+  sndbg("b1 = %d\n", priv->mpl115a_cal_b1);
+
+  /* Get b2 coefficient */
+  priv->mpl115a_cal_b2 = mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_B2_MSB << 1)) << 8;
+  priv->mpl115a_cal_b2 |= mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_B2_LSB << 1));
+  sndbg("b2 = %d\n", priv->mpl115a_cal_b2);
+
+  /* Get c12 coefficient */
+  priv->mpl115a_cal_c12 = mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_C12_MSB << 1)) << 8;
+  priv->mpl115a_cal_c12 |= mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_C12_LSB << 1));
+  sndbg("c12 = %d\n", priv->mpl115a_cal_c12);
+
+  return;
+}
+
+/****************************************************************************
+ * Name: mpl115a_read_press_temp
+ *
+ * Description:
+ *   Read raw pressure and temperature from MPL115A and store it in the
+ *   mpl115a_dev_s structure.
+ */
+static void mpl115a_read_press_temp(FAR struct mpl115a_dev_s *priv)
+{
+  uint16_t pressure;
+
+  /* Start a new convertion */
+  mpl115a_getreg8(priv, (MPL115A_CONVERT << 1));
+
+  /* Delay 5ms */
+  usleep(5000);
+
+  priv->mpl115a_pressure = mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_PADC_MSB << 1)) << 8;
+  priv->mpl115a_pressure |= mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_PADC_LSB << 1));
+  priv->mpl115a_pressure >>= 6; /* Padc is 10bit unsigned */
+
+  sndbg("Pressure = %d\n", priv->mpl115a_pressure);
+
+  priv->mpl115a_temperature = mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_TADC_MSB << 1)) << 8;
+  priv->mpl115a_temperature |= mpl115a_getreg8(priv, MPL115A_BASE_CMD | (MPL115A_TADC_LSB << 1));
+  priv->mpl115a_temperature >>= 6; /* Tadc is 10bit unsigned */
+
+  sndbg("Temperature = %d\n", priv->mpl115a_temperature);
+}
+
+/****************************************************************************
+ * Name: mpl115a_getpressure
+ *
+ * Description:
+ *   Calculate the Barometrc Pressure using the temperature compensated
+ *   See Freescale AN3785 and MPL115A1 datasheet for details
+ *
+ ****************************************************************************/
+
+static int mpl115a_getpressure(FAR struct mpl115a_dev_s *priv)
+{
+  int32_t c12x2, a1, a1x1, y1, a2x2, pcomp;
+  uint16_t padc, tadc, pressure;
+
+  /* Check if coefficient data were read correctly */
+  if ( (priv->mpl115a_cal_a0 == 0) || (priv->mpl115a_cal_b1 == 0) ||
+       (priv->mpl115a_cal_b2 == 0) || (priv->mpl115a_cal_c12 == 0) )
+    {
+      mpl115a_updatecaldata(priv);
+    }
+
+  /* Read temperature and pressure */
+  mpl115a_read_press_temp(priv);
+  padc = priv->mpl115a_pressure;
+  tadc = priv->mpl115a_temperature;
+
+  /* These code are from Freescale AN3785 */
+  c12x2 = ((int32_t)priv->mpl115a_cal_c12 * tadc) >> 11;
+  a1 = (int32_t) (priv->mpl115a_cal_b1 + c12x2);
+  a1x1 = a1 * padc;
+  y1 = (((int32_t)priv->mpl115a_cal_a0) << 10) + a1x1;
+  a2x2 = (((int32_t)priv->mpl115a_cal_b2) * tadc) >> 1;
+  pcomp = (y1 + a2x2) >> 9;
+
+  /* Calculate the pressure in 1/16 kPa from compensated */
+  pressure = (((((int32_t)pcomp) * 1041) >> 14) + 800);
+
+  /* Note that the final pressure value is reported with 4 bit fractional
+   * This may be eliminated by right shifting the result 4 bits.
+   */
+  sndbg("Final Pressure = %d\n", pressure >> 4);
+  return pressure;
+}
+
+/****************************************************************************
+ * Name: mpl115a_open
+ *
+ * Description:
+ *   This function is called whenever the MPL115A1 device is opened.
+ *
+ ****************************************************************************/
+
+static int mpl115a_open(FAR struct file *filep)
+{
+  return OK;
+}
+
+/****************************************************************************
+ * Name: mpl115a_close
+ *
+ * Description:
+ *   This routine is called when the LM-75 device is closed.
+ *
+ ****************************************************************************/
+
+static int mpl115a_close(FAR struct file *filep)
+{
+  return OK;
+}
+
+/****************************************************************************
+ * Name: mpl115a_read
+ ****************************************************************************/
+
+static ssize_t mpl115a_read(FAR struct file *filep, FAR char *buffer, size_t buflen)
+{
+  FAR struct inode         *inode = filep->f_inode;
+  FAR struct mpl115a_dev_s *priv  = inode->i_private;
+  FAR uint16_t             *press = (FAR uint16_t *) buffer;
+
+  if (!buffer)
+    {
+      sndbg("Buffer is null\n");
+      return -1;
+    }
+
+  if ( buflen != 2)
+    {
+      sndbg("You can't read something other than 16 bits (2 bytes)\n");
+      return -1;
+    }
+
+  /* Get the pressure compensated */
+  *press = mpl115a_getpressure(priv);
+
+  /* Return size of uint16_t (2 bytes) */
+  return 2;
+}
+
+/****************************************************************************
+ * Name: mpl115a_write
+ ****************************************************************************/
+
+static ssize_t mpl115a_write(FAR struct file *filep, FAR const char *buffer,
+                          size_t buflen)
+{
+  return -ENOSYS;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: mpl115a_register
+ *
+ * Description:
+ *   Register the MPL115A character device as 'devpath'
+ *
+ * Input Parameters:
+ *   devpath - The full path to the driver to register. E.g., "/dev/temp0"
+ *   i2c - An instance of the I2C interface to use to communicate with MPL115A
+ *   addr - The I2C address of the LM-75.  The base I2C address of the MPL115A
+ *   is 0x48.  Bits 0-3 can be controlled to get 8 unique addresses from 0x48
+ *   through 0x4f.
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+int mpl115a_register(FAR const char *devpath, FAR struct spi_dev_s *spi)
+{
+  FAR struct mpl115a_dev_s *priv;
+  int ret;
+
+  /* Initialize the MPL115A device structure */
+
+  priv = (FAR struct mpl115a_dev_s *)kmm_malloc(sizeof(struct mpl115a_dev_s));
+  if (!priv)
+    {
+      sndbg("Failed to allocate instance\n");
+      return -ENOMEM;
+    }
+
+  priv->spi             = spi;
+  priv->mpl115a_cal_a0  = 0;
+  priv->mpl115a_cal_b1  = 0;
+  priv->mpl115a_cal_b2  = 0;
+  priv->mpl115a_cal_c12 = 0;
+
+  /* Read the coefficient value */
+  mpl115a_updatecaldata(priv);
+
+  /* Register the character driver */
+
+  ret = register_driver(devpath, &g_mpl115afops, 0666, priv);
+  if (ret < 0)
+    {
+      sndbg("Failed to register driver: %d\n", ret);
+      kmm_free(priv);
+    }
+
+  return ret;
+}
+#endif /* CONFIG_SPI && CONFIG_MPL115A */
diff --git a/nuttx/include/nuttx/sensors/mpl115a.h b/nuttx/include/nuttx/sensors/mpl115a.h
new file mode 100644
index 000000000..c1f01ba70
--- /dev/null
+++ b/nuttx/include/nuttx/sensors/mpl115a.h
@@ -0,0 +1,120 @@
+/********************************************************************************************
+ * drivers/sensors/mpl115a.h
+ *
+ *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Author: Alan Carvalho de Assis <acassis@gmail.com>
+ *
+ * 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.
+ *
+ ********************************************************************************************/
+
+#ifndef __DRIVERS_SENSORS_MPL115A_H
+#define __DRIVERS_SENSORS_MPL115A_H
+
+#if defined(CONFIG_MPL115A)
+
+/********************************************************************************************
+ * Pre-Processor Definitions
+ ********************************************************************************************/
+/* Configuration ****************************************************************************/
+/* Prerequisites:
+ *
+ * CONFIG_SENSORS_MPL115A
+ *   Enables support for the MPL115A driver
+ * CONFIG_MPL115A_REGDEBUG
+ *   Enable very low register-level debug output.  Requires CONFIG_DEBUG.
+ */
+
+/* There are two types of MPL115A chips. The MPL115A1 communicates with the target CPU
+ * via a SPI interface. The MPL115A2 communicates via I2C interface.
+ * Note: This driver only supports MPL115A1 (SPI Interface).
+ */
+
+/* SPI **************************************************************************************/
+/* The device always operates in mode 0 */
+
+#define MPL115A_SPI_MODE            SPIDEV_MODE0 /* Mode 0 */
+
+/* SPI frequency */
+
+#define MPL115A_SPI_MAXFREQUENCY    800000       /* 8MHz */
+
+/* MPL115A Registers ************************************************************************/
+/* Register Addresses */
+
+#define MPL115A_BASE_CMD            0x80
+#define MPL115A_PADC_MSB            0x00  /* 10-bit Pressure ADC output value MSB */
+#define MPL115A_PADC_LSB            0x01  /* 10-bit Pressure ADC output value LSB */
+#define MPL115A_TADC_MSB            0x02  /* 10-bit Temperature ADC output value MSB */
+#define MPL115A_TADC_LSB            0x03  /* 10-bit Temperature ADC output value LSB */
+#define MPL115A_A0_MSB              0x04  /* a0 coefficient MSB */
+#define MPL115A_A0_LSB              0x05  /* a0 coefficient LSB */
+#define MPL115A_B1_MSB              0x06  /* b1 coefficient MSB */
+#define MPL115A_B1_LSB              0x07  /* b1 coefficient LSB */
+#define MPL115A_B2_MSB              0x08  /* b2 coefficient MSB */
+#define MPL115A_B2_LSB              0x09  /* b2 coefficient LSB */
+#define MPL115A_C12_MSB             0x0A  /* c12 coefficient MSB */
+#define MPL115A_C12_LSB             0x0B  /* c12 coefficient LSB */
+                                          /* 0x0C - 0x11 are reserved */
+#define MPL115A_CONVERT             0x12  /* Start Pressure and Temperature Conversion */
+
+/********************************************************************************************
+ * Public Function Prototypes
+ ********************************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C" {
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Name: mpl115a_register
+ *
+ * Description:
+ *   Register the MPL115A character device as 'devpath'
+ *
+ * Input Parameters:
+ *   devpath - The full path to the driver to register. E.g., "/dev/temp0"
+ *   spi - An instance of the SPI interface to use to communicate with MPL115A
+ *
+ * Returned Value:
+ *   Zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+EXTERN int mpl115a_register(FAR const char *devpath, FAR struct spi_dev_s *spi);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* CONFIG_SENSORS_MPL115A */
+#endif /* __DRIVERS_SENSORS_MPL115A_H */