cc2538: gpio: Add macros to get interrupt status

Introduce new useful GPIO macros to:
 - get the raw interrupt status of a port,
 - get the masked interrupt status of a port,
 - get the power-up interrupt status of a port.

These macros are cleaner and less error-prone than raw register access
code copied all over the place.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>

cpu/cc2538/dev/gpio.c

@@ -93,7 +93,7 @@ gpio_port_isr(uint8_t port)
 
   base = GPIO_PORT_TO_BASE(port);
 
-  notify(REG(base + GPIO_MIS), port);
+  notify(GPIO_GET_MASKED_INT_STATUS(base), port);
 
   GPIO_CLEAR_INTERRUPT(base, 0xFF);
   GPIO_CLEAR_POWER_UP_INTERRUPT(port, 0xFF);

cpu/cc2538/dev/gpio.h

@@ -210,6 +210,31 @@ typedef void (* gpio_callback_t)(uint8_t port, uint8_t pin);
 #define GPIO_DISABLE_INTERRUPT(PORT_BASE, PIN_MASK) \
   do { REG((PORT_BASE) + GPIO_IE) &= ~(PIN_MASK); } while(0)
 
+/** \brief Get raw interrupt status of port with PORT_BASE.
+ * \param PORT_BASE GPIO Port register offset
+ * \return Bit-mask reflecting the raw interrupt status of all the port pins
+ *
+ * The bits set in the returned bit-mask reflect the status of the interrupts
+ * trigger conditions detected (raw, before interrupt masking), indicating that
+ * all the requirements are met, before they are finally allowed to trigger by
+ * the interrupt mask. The bits cleared indicate that corresponding input pins
+ * have not initiated an interrupt.
+ */
+#define GPIO_GET_RAW_INT_STATUS(PORT_BASE) \
+  REG((PORT_BASE) + GPIO_RIS)
+
+/** \brief Get masked interrupt status of port with PORT_BASE.
+ * \param PORT_BASE GPIO Port register offset
+ * \return Bit-mask reflecting the masked interrupt status of all the port pins
+ *
+ * The bits set in the returned bit-mask reflect the status of input lines
+ * triggering an interrupt. The bits cleared indicate that either no interrupt
+ * has been generated, or the interrupt is masked. This is the state of the
+ * interrupt after interrupt masking.
+ */
+#define GPIO_GET_MASKED_INT_STATUS(PORT_BASE) \
+  REG((PORT_BASE) + GPIO_MIS)
+
 /** \brief Clear interrupt triggering for pins with PIN_MASK of port with
  * PORT_BASE.
  * \param PORT_BASE GPIO Port register offset
@@ -270,6 +295,14 @@ typedef void (* gpio_callback_t)(uint8_t port, uint8_t pin);
   do { REG(GPIO_PORT_TO_BASE(PORT) + GPIO_PI_IEN) &= \
        ~((PIN_MASK) << ((PORT) << 3)); } while(0)
 
+/** \brief Get power-up interrupt status of port PORT.
+ * \param PORT GPIO Port (not port base address)
+ * \return Bit-mask reflecting the power-up interrupt status of all the port
+ * pins
+ */
+#define GPIO_GET_POWER_UP_INT_STATUS(PORT) \
+  ((REG(GPIO_PORT_TO_BASE(PORT) + GPIO_IRQ_DETECT_ACK) >> ((PORT) << 3)) & 0xFF)
+
 /** \brief Clear power-up interrupt triggering for pins with PIN_MASK of port
  * PORT.
  * \param PORT GPIO Port (not port base address)