RP2040: Add gpio interrupt support

Author: giulcioffi

targets/TARGET_RASPBERRYPI/TARGET_RP2040/gpio_api.c

@@ -1,8 +1,15 @@
 #include "mbed_assert.h"
 #include "hal/gpio_api.h"
+#include "gpio_irq_api.h"
 #include "pinmap.h"
 #include "mbed_error.h"
 
+#define GPIO_PIN_COUNT 30
+
+static gpio_irq_handler m_irq_handler;
+static uint32_t m_channel_ids[GPIO_PIN_COUNT] = {0};
+static uint32_t m_pico_events[GPIO_PIN_COUNT] = {0};
+
 void gpio_write(gpio_t *obj, int value)
 {
     gpio_put(obj->pin, value);
@@ -16,16 +23,37 @@ int gpio_read(gpio_t *obj)
 void gpio_init(gpio_t *obj, PinName pin)
 {
     obj->pin = pin;
+
+    if (pin == (PinName)NC) {
+        return;
+    }
+
     _gpio_init(obj->pin);
 }
 
+static uint32_t gpio_convert_event(gpio_irq_event event)
+{
+    uint32_t irq_event = 0;
+
+    if (event == IRQ_RISE) {
+        irq_event = GPIO_IRQ_EDGE_RISE;
+    } else if (event == IRQ_FALL) {
+        irq_event = GPIO_IRQ_EDGE_FALL;
+    }
+
+    return irq_event;
+}
+
 void gpio_mode(gpio_t *obj, PinMode mode)
 {
+    MBED_ASSERT(obj->pin != (PinName)NC);
+
     gpio_set_pulls(obj->pin, mode == PullUp, mode == PullDown);
 }
 
 void gpio_dir(gpio_t *obj, PinDirection direction)
 {
+    MBED_ASSERT(obj->pin != (PinName)NC);
     obj->direction = direction;
     if (direction == PIN_OUTPUT) {
         gpio_set_dir(obj->pin, GPIO_OUT);
@@ -37,4 +65,79 @@ void gpio_dir(gpio_t *obj, PinDirection direction)
 
 int gpio_is_connected(const gpio_t *obj) {
     return (obj->pin == NC ? 0 : 1);
-}
+}
+
+
+/***********
+  GPIO IRQ
+***********/
+
+#if DEVICE_INTERRUPTIN
+
+static void _gpio_irq(uint gpio, uint32_t events)
+{
+    gpio_irq_event ev;
+    if (events == GPIO_IRQ_EDGE_RISE) {
+        ev = IRQ_RISE;
+    } else if (events == GPIO_IRQ_EDGE_FALL) {
+        ev = IRQ_FALL;
+    } else {
+        ev = IRQ_NONE;
+    }
+    m_irq_handler(m_channel_ids[gpio], ev);
+}
+
+int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id)
+{
+    if (pin == NC) {
+        return -1;
+    }
+    MBED_ASSERT((uint32_t)pin < GPIO_PIN_COUNT);
+
+    m_channel_ids[pin]          = id;
+    m_irq_handler               = handler;
+
+    obj->irq_n = IO_IRQ_BANK0;
+    obj->pin = pin;
+    obj->irq_index = id;
+
+    return 0;
+}
+
+
+void gpio_irq_free(gpio_irq_t *obj)
+{
+    gpio_irq_disable(obj);
+    obj->irq_n = 0;
+    obj->pin = 0;
+    obj->irq_index = 0;
+}
+
+
+void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable)
+{
+    uint32_t irq_event = gpio_convert_event(event);
+
+    if (enable) {
+        m_pico_events[obj->pin] |= irq_event;
+        obj->event = irq_event;
+        gpio_irq_enable(obj);
+    }
+}
+
+
+void gpio_irq_enable(gpio_irq_t *obj)
+{
+    gpio_set_irq_enabled_with_callback(obj->pin, obj->event, true, _gpio_irq);
+}
+
+
+void gpio_irq_disable(gpio_irq_t *obj)
+{
+    gpio_set_irq_enabled(obj->pin, m_pico_events[obj->pin], false);
+
+    obj->event = 0;
+    m_pico_events[obj->pin] = 0;
+}
+
+#endif