EIC: pass channel number back to caller

peripherals/eic.c

@@ -96,11 +96,11 @@ void eic_enable(void) {
 #endif
 }
 
-bool eic_configure_pin(const uint32_t pin, eic_interrupt_trigger trigger) {
+int8_t eic_configure_pin(const uint32_t pin, eic_interrupt_trigger trigger) {
     uint16_t port = pin >> 8;
     int8_t channel = _eic_pin_to_channel[port][pin % 32];
     if (channel < 0) {
-        return false;
+        return -1;
     }
     uint8_t config_index = (channel > 7) ? 1 : 0;
     uint8_t sense_pos = 4 * (channel % 8);
@@ -122,7 +122,7 @@ bool eic_configure_pin(const uint32_t pin, eic_interrupt_trigger trigger) {
     CTRLREG.bit.ENABLE = 1;
     _eic_sync();
 
-    return true;
+    return channel;
 }
 
 bool eic_enable_interrupt(const uint8_t pin) {

peripherals/eic.h

@@ -56,10 +56,11 @@ void eic_enable(void);
   *          eic_enable_event() to either wake the processor or generate an event for a peripheral.
   * @param pin The external interrupt pin you wish to configure
   * @param trigger The condition on which you wish to trigger: rising, falling or both.
+  * @return the EIC channel number associated with the pin, or -1 if the pin is not an interrupt pin.
   * @note Be sure to check your pin multiplexing table to ensure that you do not have multiple pins
   *       assigned to the same interrupt channel.
   */
-bool eic_configure_pin(const uint32_t pin, eic_interrupt_trigger trigger);
+int8_t eic_configure_pin(const uint32_t pin, eic_interrupt_trigger trigger);
 
 /** @brief Enables an interrupt on the given interrupt channel.
   * @param pin The external interrupt pin.