Add gpio event driver

src/platform/nrf52/gpio.cc

@@ -46,7 +46,7 @@ void Gpio::set_direction(direction dir, bool blocking_read)
         drive = GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos;
         sense = GPIO_PIN_CNF_SENSE_Low << GPIO_PIN_CNF_SENSE_Pos;
 
-        gpiote.instance().register_handler(Gpiote::GpioteChannel::CHANNEL_0, *this);
+        gpiote.instance().register_handler(this);
 
         this->blocking = blocking_read;
 

src/platform/nrf52/gpiote.cc

@@ -16,7 +16,11 @@ using namespace pinetime::platform::nrf52;
 
 Gpiote::Gpiote()
     : InterruptHandler(InterruptGuardian::Nrf52IrqN::GPIOTE_IRQ)
+    , num_registered(0)
 {
+    for(auto it = this->gpiote_channels.begin(); it != this->gpiote_channels.end(); ++it) {
+        *it = nullptr;
+    }
 }
 
 void Gpiote::enable()
@@ -30,17 +34,34 @@ void Gpiote::disable()
     NVIC_DisableIRQ(GPIOTE_IRQn);
 }
 
-void Gpiote::register_handler(GpioteChannel channel, pinetime::interfaces::GpioInterface & gpio)
+void Gpiote::register_handler(pinetime::interfaces::GpioInterface *gpio)
 {
-    unsigned int idx = static_cast<unsigned int>(channel);
-    this->gpiote_channels[idx] = &gpio;
-
-    GPIOTE_REGS->INTENSET = GPIOTE_INTENSET_IN0_Msk;
-    GPIOTE_REGS->CONFIG[idx] = (GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos)
-                             | ((gpio.pin_number()) << GPIOTE_CONFIG_PSEL_Pos)
-                             | (GPIOTE_CONFIG_MODE_Event << GPIOTE_CONFIG_MODE_Pos);
-
+    if(num_registered == GPIOTE_CHANNELS) {
+        //FIXME: Error notification
+        return;
+    }
 
+    if(num_registered == 0) {
+        this->enable();
+    } else {
+        //check if gpio already registered
+        for(auto it = this->gpiote_channels.begin(); it != this->gpiote_channels.end(); ++it) {
+            if(*it == gpio) {
+                return;
+            }
+        }
+    }
+    uint32_t i = 0;
+    for(auto it = this->gpiote_channels.begin(); it != this->gpiote_channels.end(); ++it) {
+        if(*it == nullptr) {
+            *it = gpio;
+            GPIOTE_REGS->INTENSET = GPIOTE_INTENSET_IN0_Msk;
+            GPIOTE_REGS->CONFIG[i] = (GPIOTE_CONFIG_POLARITY_Toggle << GPIOTE_CONFIG_POLARITY_Pos)
+                                   | ((gpio->pin_number()) << GPIOTE_CONFIG_PSEL_Pos)
+                                   | (GPIOTE_CONFIG_MODE_Event << GPIOTE_CONFIG_MODE_Pos);
+        }
+        i++;
+    }
 }
 
 void Gpiote::handle()

src/platform/nrf52/gpiote.h

@@ -26,18 +26,7 @@ public:
     void enable() override;
     void disable() override;
 
-    enum class GpioteChannel {
-        CHANNEL_0 = 0,
-        CHANNEL_1,
-        CHANNEL_2,
-        CHANNEL_3,
-        CHANNEL_4,
-        CHANNEL_5,
-        CHANNEL_6,
-        CHANNEL_7,
-    };
-
-    void register_handler(GpioteChannel, pinetime::interfaces::GpioInterface &);
+    void register_handler(pinetime::interfaces::GpioInterface *);
 
 private:
     void handle() override;
@@ -47,7 +36,7 @@ private:
     };
 
     std::array<pinetime::interfaces::GpioInterface *, GPIOTE_CHANNELS> gpiote_channels;
-
+    uint32_t num_registered;
 };
 
 }