led: update to use gpioled if desired, better C code wrapper

Signed-off-by: Mihai Tudor Panu <mihai.tudor.panu@intel.com>

src/led/led.c

@@ -42,29 +42,85 @@ led_context led_init(int pin){
     if (!dev)
         return NULL;
 
+    dev->name = NULL;
+    dev->gpioled = NULL;
+
     dev->led_pin = pin;
     dev->gpio = mraa_gpio_init(dev->led_pin);
 
-    if (mraa_gpio_dir(dev->gpio, MRAA_GPIO_OUT) != MRAA_SUCCESS)
+    if (mraa_gpio_dir(dev->gpio, MRAA_GPIO_OUT) != MRAA_SUCCESS) {
+        printf("%s: Unable to set pin %d as output.\n", __FUNCTION__, pin);
+        free(dev);
         return NULL;
+    }
+
+    return dev;
+}
+
+led_context led_init_str(const char* name){
+    // make sure MRAA is initialized
+    int mraa_rv;
+    if ((mraa_rv = mraa_init()) != MRAA_SUCCESS)
+    {
+        printf("%s: mraa_init() failed (%d).\n", __FUNCTION__, mraa_rv);
+        return NULL;
+    }
+
+    led_context dev =
+      (led_context)malloc(sizeof(struct _led_context));
+
+    if (!dev)
+        return NULL;
+
+    dev->led_pin = -1;
+    dev->gpio = NULL;
+
+    dev->name = name;
+    dev->gpioled = mraa_led_init(name);
+
+    if (!dev->gpioled) {
+        printf("%s: Unable to initialize gpioled device (%s).\n", __FUNCTION__, dev->name);
+        free(dev);
+        return NULL;
+    }
+
+    dev->max_brightness = mraa_led_read_max_brightness(dev->gpioled);
 
     return dev;
 }
 
 void led_close(led_context dev){
+    if (dev->gpio) {
+        mraa_gpio_close(dev->gpio);
+    }
+    if (dev->gpioled) {
+        mraa_led_close(dev->gpioled);
+    }
     free(dev);
 }
 
 upm_result_t led_on(led_context dev){
+    if (dev->gpio) {
+        // using gpio pin
         if (mraa_gpio_write(dev->gpio, 1) != MRAA_SUCCESS)
             return UPM_ERROR_OPERATION_FAILED;
-
+    } else {
+        // using gpioled device
+        if (mraa_led_set_brightness(dev->gpioled, dev->max_brightness) != MRAA_SUCCESS)
+            return UPM_ERROR_OPERATION_FAILED;
+    }
     return UPM_SUCCESS;
 }
 
 upm_result_t led_off(led_context dev){
+    if (dev->gpio) {
+        // using gpio pin
         if (mraa_gpio_write(dev->gpio, 0) != MRAA_SUCCESS)
             return UPM_ERROR_OPERATION_FAILED;
-
+    } else {
+        // using gpioled device
+        if (mraa_led_set_brightness(dev->gpioled, 0) != MRAA_SUCCESS)
+            return UPM_ERROR_OPERATION_FAILED;
+    }
     return UPM_SUCCESS;
 }

src/led/led.cxx

@@ -35,33 +35,41 @@ using namespace upm;
 
 Led::Led(int pin)
 {
-    if ( !(m_gpio = mraa_gpio_init(pin)) ) {
+    if ( !(m_led = led_init(pin)) ) {
         throw std::invalid_argument(std::string(__FUNCTION__) +
                                     ": mraa_gpio_init() failed, invalid pin?");
         return;
     }
-    mraa_gpio_dir(m_gpio, MRAA_GPIO_OUT);
+}
+
+Led::Led(std::string name)
+{
+    if ( !(m_led = led_init_str(name.c_str())) ) {
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                                    ": mraa_led_init() failed, invalid led name?");
+        return;
+    }
 }
 
 Led::~Led()
 {
-    mraa_gpio_close(m_gpio);
+    led_close(m_led);
 }
 
-mraa_result_t Led::write(int value)
+upm_result_t Led::write(int value)
 {
     if (value >= 1) {
-        return mraa_gpio_write(m_gpio, 1);
+        return led_on(m_led);
     }
-    return mraa_gpio_write(m_gpio, 0);
+    return led_off(m_led);
 }
 
-mraa_result_t Led::on()
+upm_result_t Led::on()
 {
     return write(1);
 }
 
-mraa_result_t Led::off()
+upm_result_t Led::off()
 {
     return write(0);
 }

src/led/led.h

@@ -33,6 +33,11 @@
 #include <stdint.h>
 #include "upm.h"
 #include "mraa/gpio.h"
+#include "mraa/led.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 /**
  * @file led.h
@@ -47,7 +52,10 @@
  */
 typedef struct _led_context {
     mraa_gpio_context        gpio;
+    mraa_led_context         gpioled;
     int                      led_pin;
+    const char*              name;
+    int                      max_brightness;
 } *led_context;
 
 /**
@@ -58,6 +66,14 @@ typedef struct _led_context {
  */
 led_context led_init(int pin);
 
+/**
+ * LED Initialization function
+ *
+ * @param name Linux gpioled device to use
+ * @return The sensor context
+ */
+led_context led_init_str(const char* name);
+
 /**
  * LED Initialization function
  *
@@ -81,4 +97,8 @@ upm_result_t led_on(led_context dev);
  */
 upm_result_t led_off(led_context dev);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* LED_LED_H_ */

src/led/led.hpp

@@ -27,7 +27,6 @@
 #pragma once
 
 #include <string>
-#include <mraa/gpio.hpp>
 #include "led.h"
 
 namespace upm {
@@ -67,6 +66,12 @@ class Led {
          * @param pin Pin to use
          */
         Led(int pin);
+        /**
+         * LED constructor
+         *
+         * @param name Linux gpioled device name
+         */
+        Led(std::string name);
         /**
          * LED destructor
          */
@@ -82,24 +87,24 @@ class Led {
          *
          * @return 0 if successful, non-zero otherwise
          */
-        mraa_result_t write(int value);
+        upm_result_t write(int value);
         /**
          * Turns the LED off
          *
          * @return 0 if successful, non-zero otherwise
          */
-        mraa_result_t off();
+        upm_result_t off();
         /**
          * Turns the LED on
          *
          * @return 0 if successful, non-zero otherwise
          */
-        mraa_result_t on();
+        upm_result_t on();
         std::string name()
         {
             return "LED Sensor";
         }
     private:
-        mraa_gpio_context m_gpio;
+        led_context m_led;
 };
 }