drivers/jc42: Add JEDEC JC42.4 temperature sensors

This patch adds a driver for the jc42 compatible
temperature sensors. All sensors compatible with
jc42.4 should work. Examples include the mcp9808
and more.

drivers/Makefile.include

@@ -64,6 +64,9 @@ endif
 ifneq (,$(filter bmp180,$(USEMODULE)))
     USEMODULE_INCLUDES += $(RIOTBASE)/drivers/bmp180/include
 endif
+ifneq (,$(filter jc42,$(USEMODULE)))
+    USEMODULE_INCLUDES += $(RIOTBASE)/drivers/jc42/include
+endif
 ifneq (,$(filter cc2420,$(USEMODULE)))
     USEMODULE_INCLUDES += $(RIOTBASE)/drivers/cc2420/include
 endif

drivers/include/jc42.h

@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2017 Koen Zandberg
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @defgroup    drivers_jc42 JC42 compliant temperature sensor driver
+ * @ingroup     drivers_sensors
+ *
+ * @brief       JC42 compliant temperature sensor driver
+ *
+ * ## Description
+ *
+ * The connection between the MCU and jc42 compliant temperature sensors is
+ * based on a I2C-interface. There are multiple jc42 compliant temperature
+ * sensors available such as the mcp9804 and the MAX6604. This driver reads the
+ * temperature from these sensors. The sensors support a alarm wire, but this
+ * is not supported by this driver.
+ *
+ * @{
+ *
+ * @file
+ * @brief       Driver for jc42 compliant temperature sensors
+ *
+ * @author      Koen Zandberg <koen@bergzand.net>
+ */
+
+#ifndef JC42_TEMP_H_
+#define JC42_TEMP_H_
+
+#include <stdint.h>
+#include "periph/i2c.h"
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @name jc42 status return codes
+ * @{
+ */
+#define JC42_OK                       (0)
+#define JC42_NOI2C                    (-1)
+#define JC42_NODEV                    (-2)
+/** @} */
+
+
+/**
+  * @brief   Device descriptor for a jc42 device
+  */
+typedef struct {
+    i2c_t i2c;          /**< I2C device that sensor is connected to */
+    uint8_t addr;       /**< I2C address of this particular sensor */
+} jc42_t;
+
+/**
+ * @brief Device initialization parameters
+ */
+typedef struct {
+    i2c_t i2c;	        /**< I2C device that sensor is connected to */
+    i2c_speed_t speed;  /**< I2C device speed */
+    uint8_t addr;       /**< Configured address of the sensor */
+} jc42_params_t;
+
+/**
+ * @brief export SAUL endpoint
+ */
+extern const saul_driver_t jc42_temperature_saul_driver;
+
+/**
+ * @brief   Initialize a jc42 device
+ *
+ * @param[out] dev          device descriptor
+ * @param[in]  params       jc42 initialization struct
+ *
+ *
+ * @return                   0 on success
+ * @return                  -1 on error
+ */
+int jc42_init(jc42_t* dev, jc42_params_t* params);
+
+/**
+ * @brief   Get content of configuration register
+ *
+ * @param[in] dev           device descriptor
+ * @param[out] data         buffer where config register will be written to
+ *
+ * @return                   0 on success
+ * @return                  -1 on error
+ */
+int jc42_get_config(jc42_t* dev, uint16_t* data);
+
+/**
+ * @brief   Set content of configuration register
+ *
+ * @param[in] dev           device descriptor
+ * @param[in] data          new value for configuration register
+ *
+ * @return                   0 on success
+ * @return                  -1 on error
+ */
+int jc42_set_config(jc42_t* dev, uint16_t data);
+
+
+/**
+ * @brief   Get measured temperature
+ *
+ * @param[in] dev           device descriptor
+ * @param[out] temperature  uint16_t buffer where temperature will be written to in centi-degree
+ *
+ * @return                   0 on success
+ * @return                  -1 on error
+ */
+int jc42_get_temperature(jc42_t* dev, uint16_t* temperature);
+
+#ifdef __cplusplus
+}
+#endif
+
+/** @} */
+#endif /* JC42_TEMP_H_ */

drivers/jc42/Makefile

@@ -0,0 +1,2 @@
+MODULE = jc42
+include $(RIOTBASE)/Makefile.base

drivers/jc42/include/jc42_internal.h

@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2017 Koen Zandberg
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     drivers_sensors
+ * @{
+ *
+ * @file
+ * @brief       Internal addresses, registers, constants for jc42 sensors.
+ *
+ * @author      Koen Zandberg <koen@bergzand.net>
+ */
+
+#ifndef JC42_INTERNAL_H_
+#define JC42_INTERNAL_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @name JC42 register addresses
+ * @{
+ */
+#define JC42_REG_CAP           	        (0x00)
+#define JC42_REG_CONFIG        	        (0x01)
+#define JC42_REG_TEMP_UPPER             (0x02)
+#define JC42_REG_TEMP_LOWER             (0x03)
+#define JC42_REG_TEMP_CRITICAL          (0x04)
+#define JC42_REG_TEMP                   (0x05)
+#define JC42_REG_MANID                  (0x06)
+#define JC42_REG_DEVICEID               (0x07)
+
+#define jc42_BUS_FREE_TIME_US		(1)
+/** @} */
+
+
+#ifdef __cplusplus
+}
+#endif
+
+/** @} */
+
+
+#endif /* JC42_INTERNAL_H_ */

drivers/jc42/include/jc42_params.h

@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2017 Koen Zandberg <koen@bergzand.net>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     drivers_jc42
+ *
+ * @{
+ * @file
+ * @brief       Default configuration for jc42
+ *
+ * @author      Koen Zandberg <koen@bergzand.net>
+ */
+
+#ifndef JC42_PARAMS_H
+#define JC42_PARAMS_H
+
+#include "board.h"
+#include "jc42.h"
+#include "periph/i2c.h"
+#include "saul_reg.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   Set default configuration parameters for the JC42
+ * @{
+ */
+#ifndef JC42_PARAM_I2C_DEV
+#define JC42_PARAM_I2C_DEV         (0)
+#endif
+#ifndef JC42_PARAM_ADDR
+#define JC42_PARAM_ADDR            (0x18)
+#endif
+#ifndef JC42_PARAM_SPEED
+#define JC42_PARAM_SPEED           I2C_SPEED_FAST
+#endif
+
+#define JC42_PARAMS_DEFAULT        {.i2c = JC42_PARAM_I2C_DEV,  \
+                                      .speed    = JC42_PARAM_SPEED, \
+                                      .addr     = JC42_PARAM_ADDR }
+/**@}*/
+
+/**
+ * @brief   Configure JC42
+ */
+static const jc42_params_t jc42_params[] =
+{
+#ifdef JC42_PARAMS_BOARD
+    JC42_PARAMS_BOARD,
+#else
+    JC42_PARAMS_DEFAULT,
+#endif
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* JC42_PARAMS_H */
+/** @} */

drivers/jc42/jc42.c

@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2017 Koen Zandberg
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     drivers_jc42
+ * @{
+ *
+ * @file
+ * @brief       Device driver implementation for the JEDEC jc42.4 compliant temperature sensors
+ *
+ * @author      Koen Zandberg <koen@bergzand.net>
+ *
+ * @}
+ */
+
+
+#include "periph/i2c.h"
+#include "byteorder.h"
+#include "xtimer.h"
+#include "saul.h"
+
+#include "jc42.h"
+#include "jc42_params.h"
+#include "jc42_internal.h"
+
+#define ENABLE_DEBUG (0)
+#include "debug.h"
+
+static int jc42_get_register(jc42_t* dev, uint8_t reg, uint16_t* data)
+{
+    i2c_acquire(dev->i2c);
+    if (i2c_read_regs(dev->i2c, dev->addr, reg, data, 2) <= 0) {
+        DEBUG("[jc42] Problem reading register 0x%x\n", reg);
+        i2c_release(dev->i2c);
+        return JC42_NODEV;
+    }
+    i2c_release(dev->i2c);
+    return JC42_OK;
+}
+
+static int jc42_set_register(jc42_t* dev, uint8_t reg, uint16_t* data)
+{
+    i2c_acquire(dev->i2c);
+    if (i2c_write_regs(dev->i2c, dev->addr, reg, data, 2) <= 0) {
+        DEBUG("[jc42] Problem writing to register 0x%x\n", reg);
+        i2c_release(dev->i2c);
+        return JC42_NODEV;
+    }
+    i2c_release(dev->i2c);
+
+    return JC42_OK;
+}
+
+int jc42_get_config(jc42_t* dev, uint16_t* data)
+{
+    return jc42_get_register(dev, JC42_REG_CONFIG, data);
+}
+
+int jc42_set_config(jc42_t* dev, uint16_t data)
+{
+    return jc42_set_register(dev, JC42_REG_CONFIG, &data);
+}
+
+int jc42_get_temperature(jc42_t* dev, uint16_t* temperature)
+{
+    struct { signed int x:12;} s;
+    uint16_t tmp;
+
+    /* Read temperature */
+    if(jc42_get_register(dev, JC42_REG_TEMP, &tmp) != 0) {
+        return JC42_NODEV;
+    }
+    tmp = NTOHS(tmp);
+    /* Convert fixed point to uint16_t */
+    *temperature = ((s.x = tmp)*100)>>4;
+    return JC42_OK;
+}
+
+int jc42_init(jc42_t* dev, jc42_params_t* params)
+{
+    uint16_t config;
+    dev->i2c = params->i2c;
+    dev->addr = params->addr;
+    i2c_acquire(dev->i2c);
+    if(i2c_init_master(dev->i2c, params->speed) != 0) {
+        DEBUG("[jc42] Problem initializing I2C master\n");
+        i2c_release(dev->i2c);
+        return JC42_NOI2C;
+    }
+    i2c_release(dev->i2c);
+
+    /* Poll the device, fail if unavailable */
+    if(jc42_get_config(dev, &config) != 0) {
+        return JC42_NODEV;
+    }
+
+    DEBUG("[jc42] Config: 0x%x\n", config);
+
+    return JC42_OK;
+}

drivers/jc42/jc42_saul.c

@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2017 Koen Zandberg <koen@bergzand.net>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     drivers_jc42
+ * @{
+ *
+ * @file
+ * @brief       SAUL adaption for jc42 compatible device
+ *
+ * @author      Koen Zandberg <koen@bergzand.net>
+ *
+ * @}
+ */
+
+#include <string.h>
+
+#include "saul.h"
+#include "jc42.h"
+
+
+
+static int read_temperature(void *dev, phydat_t *res)
+{
+    uint16_t temperature;
+    jc42_t *d = (jc42_t *)dev;
+
+    jc42_get_temperature(d, &temperature);
+    res->val[0] = temperature;
+    res->unit = UNIT_TEMP_C;
+    res->scale = -2;
+    return 1;
+}
+
+const saul_driver_t jc42_temperature_saul_driver = {
+    .read = read_temperature,
+    .write = saul_notsup,
+    .type = SAUL_SENSE_TEMP
+};

sys/auto_init/auto_init.c

@@ -294,6 +294,10 @@ void auto_init(void)
     extern void auto_init_bmp180(void);
     auto_init_bmp180();
 #endif
+#ifdef MODULE_JC42
+    extern void auto_init_jc42(void);
+    auto_init_jc42();
+#endif
 
 #endif /* MODULE_AUTO_INIT_SAUL */
 

sys/auto_init/saul/auto_init_jc42.c

@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2017 Koen Zandberg
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     auto_init_saul
+ * @{
+ *
+ * @file
+ * @brief       Auto initialization of jc42 compatible driver.
+ *
+ * @author      Koen Zandberg <koen@bergzand.net>
+ *
+ * @}
+ */
+
+#ifdef MODULE_JC42
+
+#include "log.h"
+#include "saul_reg.h"
+
+#include "jc42.h"
+#include "jc42_params.h"
+
+/**
+ * @brief   Define the number of configured sensors
+ */
+#define JC42_NUMOF    (sizeof(jc42_params) / sizeof(jc42_params[0]))
+
+/**
+ * @brief   Allocation of memory for device descriptors
+ */
+static jc42_t jc42_devs[JC42_NUMOF];
+
+/**
+ * @brief   Memory for the SAUL registry entries
+ */
+static saul_reg_t saul_entries[JC42_NUMOF];
+
+/**
+ * @brief   Reference the driver structs.
+ * @{
+ */
+extern const saul_driver_t jc42_temperature_saul_driver;
+/** @} */
+
+/**
+ * @brief   Allocate and configure entries to the SAUL registry
+ */
+saul_reg_t jc42_saul_reg_info[]=
+{
+    {
+        .name= "jc42",
+        .driver = &jc42_temperature_saul_driver
+    }
+};
+
+void auto_init_jc42(void)
+{
+    for (unsigned i = 0; i < JC42_NUMOF; i++) {
+        const jc42_params_t *p = &jc42_params[i];
+        if (jc42_init(&jc42_devs[i],
+                        (jc42_params_t*) p) < 0) {
+            LOG_ERROR("Unable to initialize jc42 sensor #%i\n", i);
+            return;
+        }
+
+
+        /* temperature */
+        saul_entries[i].dev = &(jc42_devs[i]);
+        saul_entries[i].name = jc42_saul_reg_info[i].name;
+        saul_entries[i].driver = &jc42_temperature_saul_driver;
+
+        /* register to saul */
+        saul_reg_add(&(saul_entries[i]));
+    }
+}
+#else
+typedef int dont_be_pedantic;
+#endif /* MODULE_JC42 */