Add support to Maxim MAX31855 Thermocouple-to-Digital

include/nuttx/sensors/max31855.h

@@ -0,0 +1,98 @@
+/****************************************************************************
+ * include/nuttx/input/max31855.h
+ *
+ *   Copyright (C) 2014-2015 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 __INCLUDE_NUTTX_SENSORS_MAX31855_H
+#define __INCLUDE_NUTTX_SENSORS_MAX31855_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/irq.h>
+
+#if defined(CONFIG_MAX31855)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+#define MAX31855_SPI_MAXFREQ 4000000
+
+struct spi_dev_s;
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Name: max31855_register
+ *
+ * Description:
+ *  This function will register the max31855 driver as /dev/tempN
+ *  where N is the minor device number
+ *
+ * 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
+ *             MAX31855
+ *
+ * Returned Value:
+ *   Zero is returned on success.  Otherwise, a negated errno value is
+ *   returned to indicate the nature of the failure.
+ *
+ ****************************************************************************/
+
+int max31855_register(FAR const char *devpath, FAR struct spi_dev_s *spi);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* CONFIG_MAX31855 */
+#endif /* __INCLUDE_NUTTX_SENSORS_MAX31855_H */

include/nuttx/spi/spi.h

@@ -364,6 +364,7 @@ enum spi_dev_e
   SPIDEV_EEPROM,        /* Select SPI EEPROM device */
   SPIDEV_ACCELEROMETER, /* Select SPI Accelerometer device */
   SPIDEV_BAROMETER,     /* Select SPI Pressure/Barometer device */
+  SPIDEV_TEMPERATURE,   /* Select SPI Temperature sensor device */
   SPIDEV_USER           /* Board-specific values start here */
 };