drivers/dht: optimized DHT driver

- added default dht_params.h file
- added dht_auto_init(void) function
- changed init function to init(dev, params)
- s/gpio/pin/ in device descriptor
- moved FEATURE_REQUIRED to drivers/Makefile.dep

drivers/Makefile.dep

@@ -22,6 +22,7 @@ endif
 
 ifneq (,$(filter dht,$(USEMODULE)))
     USEMODULE += xtimer
+    FEATURES_REQUIRED = periph_gpio
 endif
 
 ifneq (,$(filter enc28j60,$(USEMODULE)))

drivers/dht/dht.c

@@ -1,6 +1,7 @@
 /*
  * Copyright 2015 Ludwig Knüpfer
- * Copyright 2015 Christian Mehlis
+ *           2015 Christian Mehlis
+ *           2016 Freie Universität Berlin
  *
  * 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
@@ -17,17 +18,21 @@
  *
  * @author      Ludwig Knüpfer <ludwig.knuepfer@fu-berlin.de>
  * @author      Christian Mehlis <mehlis@inf.fu-berlin.de>
+ * @author      Hauke Petersen <hauke.petersen@fu-berlin.de>
  *
  * @}
  */
 
 #include <stdint.h>
+#include <string.h>
 
+#include "log.h"
 #include "xtimer.h"
 #include "timex.h"
 #include "periph/gpio.h"
 
 #include "dht.h"
+#include "dht_params.h"
 
 #define ENABLE_DEBUG    (0)
 #include "debug.h"
@@ -131,17 +136,27 @@ static void dht_read_data(gpio_t dev, uint32_t *data, uint8_t *checksum)
  * public API implementation
  **********************************************************************/
 
-int dht_init(dht_t *dev, dht_type_t type, gpio_t gpio)
+dht_t dht_devs[DHT_NUMOF];
+
+void dht_auto_init(void)
+{
+    for (unsigned i = 0; i < DHT_NUMOF; i++) {
+        if (dht_init(&dht_devs[i], &dht_params[i]) < 0) {
+            LOG_ERROR("Unable to initialize DHT sensor #%i\n", i);
+        }
+    }
+}
+
+int dht_init(dht_t *dev, const dht_params_t *params)
 {
     DEBUG("dht_init\n");
 
-    dev->gpio = gpio;
+    memcpy(dev, params, sizeof(dht_t));
-    dev->type = type;
 
-    if (gpio_init(gpio, GPIO_DIR_OUT, GPIO_PULLUP) == -1) {
+    if (gpio_init(dev->pin, GPIO_DIR_OUT, GPIO_PULLUP) == -1) {
         return -1;
     }
-    gpio_set(gpio);
+    gpio_set(dev->pin);
 
     xtimer_usleep(2000 * MS_IN_USEC);
 
@@ -149,14 +164,13 @@ int dht_init(dht_t *dev, dht_type_t type, gpio_t gpio)
     return 0;
 }
 
-
 int dht_read_raw(dht_t *dev, dht_data_t *outdata)
 {
     uint32_t data;
     uint8_t checksum;
 
     /* read raw data */
-    dht_read_data(dev->gpio, &data, &checksum);
+    dht_read_data(dev->pin, &data, &checksum);
 
     /* check checksum */
     int ret = dht_test_checksum(data, checksum);

drivers/dht/include/dht_params.h

@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2016 Freie Universität Berlin
+ *
+ * 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_dht
+ *
+ * @{
+ * @file
+ * @brief       Default configuration for DHT devices
+ *
+ * @author      Hauke Petersen <hauke.petersen@fu-berlin.de>
+ */
+
+#ifndef DHT_PARAMS_H
+#define DHT_PARAMS_H
+
+#include "board.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   Set default configuration parameters for the DHT devices
+ * @{
+ */
+#ifndef DHT_PARAM_PIN
+#define DHT_PARAM_PIN               (GPIO_PIN(0, 0))
+#endif
+#ifndef DHT_PARAM_TYPE
+#define DHT_PARAM_TYPE              (DHT11)
+#endif
+
+#define DHT_PARAMS_DEFAULT          {.pin = DHT_PARAM_PIN, \
+                                     .type = DHT_PARAM_TYPE}
+/**@}*/
+
+/**
+ * @brief   Configure DHT devices
+ */
+static const dht_params_t dht_params[] =
+{
+#ifdef DHT_PARAMS_BOARD
+    DHT_PARAMS_BOARD,
+#else
+    DHT_PARAMS_DEFAULT,
+#endif
+};
+
+/**
+ * @brief   Get the number of configured DHT devices
+ */
+#define DHT_NUMOF       (sizeof(dht_params) / sizeof(dht_params[0]))
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* DHT_PARAMS_H */
+/** @} */

drivers/include/dht.h

@@ -1,5 +1,7 @@
 /*
- * Copyright 2015 Ludwig Knüpfer, Christian Mehlis
+ * Copyright 2015 Ludwig Knüpfer,
+ *           2015 Christian Mehlis
+ *           2016 Freie Universität Berlin
  *
  * 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
@@ -20,6 +22,7 @@
  *
  * @author      Ludwig Knüpfer <ludwig.knuepfer@fu-berlin.de
  * @author      Christian Mehlis <mehlis@inf.fu-berlin.de>
+ * @author      Hauke Petersen <hauke.petersen@fu-berlin.de>
  */
 
 #ifndef DHT_H
@@ -54,21 +57,30 @@ typedef enum {
  * @brief device descriptor for DHT sensor devices
  */
 typedef struct {
-    gpio_t gpio;            /**< GPIO pin of the device's data pin */
+    gpio_t pin;             /**< GPIO pin of the device's data pin */
     dht_type_t type;        /**< type of the DHT device */
 } dht_t;
 
+/**
+ * @brief configuration parameters for DHT devices
+ */
+typedef dht_t dht_params_t;
+
+/**
+ * @brief auto-initialize all configured DHT devices
+ */
+void dht_auto_init(void);
+
 /**
  * @brief initialize a new DHT device
  *
- * @param[in] dev       device descriptor of a DHT device
+ * @param[out] dev      device descriptor of a DHT device
- * @param[in] type      type of the DHT device
+ * @param[in]  params   configuration parameters
- * @param[in] gpio      GPIO pin the device's data pin is connected to
  *
  * @return              0 on success
  * @return              -1 on error
  */
-int dht_init(dht_t *dev, dht_type_t type, gpio_t gpio);
+int dht_init(dht_t *dev, const dht_params_t *params);
 
  /**
  * @brief   read sensor data from device