port EIC functions to gossamer framework

Makefile

@@ -16,6 +16,7 @@ SRCS += \
   ./app.c \
   ./watch-library/hardware/watch/watch.c \
   ./watch-library/hardware/watch/watch_buzzer.c \
+  ./watch-library/hardware/watch/watch_extint.c \
   ./watch-library/hardware/watch/watch_led.c \
   ./watch-library/hardware/watch/watch_private.c \
   ./watch-library/hardware/watch/watch_rtc.c \

watch-library/hardware/watch/watch_extint.c

@@ -0,0 +1,55 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 Joey Castillo
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "watch_extint.h"
+#include <stdio.h>
+
+watch_cb_t eic_callbacks[16] = { NULL };
+
+void watch_eic_callback(uint8_t channel);
+
+void watch_enable_external_interrupts(void) {
+    eic_init();
+    eic_configure_callback(watch_eic_callback);
+    eic_enable();
+}
+
+void watch_disable_external_interrupts(void) {
+    eic_disable();
+}
+
+void watch_register_interrupt_callback(const uint8_t pin, watch_cb_t callback, eic_interrupt_trigger trigger) {
+    int8_t channel = eic_configure_pin(pin, trigger);
+    if (channel >= 0 && channel < 16) {
+        printf("Configured pin %d on channel %d\n", pin, channel);
+        eic_enable_interrupt(pin);
+        eic_callbacks[channel] = callback;
+    }
+}
+
+void watch_eic_callback(uint8_t channel) {
+    if (eic_callbacks[channel] != NULL) {
+        eic_callbacks[channel]();
+    }
+}

watch-library/shared/watch/watch.h

@@ -62,7 +62,7 @@ typedef void (*watch_cb_t)(void);
 
 #include "watch_rtc.h"
 #include "watch_slcd.h"
-// #include "watch_extint.h"
+#include "watch_extint.h"
 #include "watch_led.h"
 #include "watch_buzzer.h"
 // #include "watch_adc.h"

watch-library/shared/watch/watch_extint.h

@@ -0,0 +1,72 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 Joey Castillo
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#pragma once
+
+////< @file watch_extint.h
+
+#include "watch.h"
+#include "eic.h"
+
+/** @addtogroup buttons Buttons & External Interrupts
+  * @brief This section covers functions related to the three buttons: Light, Mode and Alarm, as well as
+  *        external interrupts from devices on the nine-pin connector.
+  * @details The buttons are the core input UI of the watch, and the way the user will interact with
+  *          your application. They are active high, pulled down by the microcontroller, and triggered
+  *          when one of the "pushers" brings a tab from the metal frame into contact with the edge
+  *          of the board. Note that the buttons can only wake the watch from STANDBY mode, at least as
+  *          of the current SAM L22 silicon revision. The external interrupt controller runs in STANDBY
+  *          mode, but it does not run in BACKUP mode; to wake from BACKUP, buttons will not cut it.
+  */
+/// @{
+
+/// @brief Enables the external interrupt controller.
+void watch_enable_external_interrupts(void);
+
+/// @brief Disables the external interrupt controller.
+void watch_disable_external_interrupts(void);
+
+/** @brief Configures an external interrupt callback on one of the external interrupt pins.
+  * @details You can set one interrupt callback per pin, and you can monitor for a rising condition,
+  *          a falling condition, or both. If you just want to detect a button press, register your
+  *          interrupt with INTERRUPT_TRIGGER_RISING; if you want to detect an active-low interrupt
+  *          signal from a device on the nine-pin connector, use INTERRUPT_TRIGGER_FALLING. If you
+  *          want to detect both rising and falling conditions (i.e. button down and button up), use
+  *          INTERRUPT_TRIGGER_BOTH and use watch_get_pin_level to check the pin level in your callback
+  *          to determine which condition caused the interrupt.
+  * @param pin One of BTN_LIGHT, BTN_MODE, BTN_ALARM, A0, A1, A3 or A4. If the pin parameter matches one of
+  *            the three button pins, this function will also enable an internal pull-down resistor. If
+  *            the pin parameter is A0-A4, you are responsible for setting any required pull configuration
+  *            using watch_enable_pull_up or watch_enable_pull_down.
+  * @param callback The function you wish to have called when the button is pressed.
+  * @param trigger The condition on which you wish to trigger: rising, falling or both.
+  * @note Pins A2 and A4 can also generate interrupts via the watch_register_extwake_callback function, which
+  *       will allow them to trigger even when the watch is in deep sleep mode.
+  * @warning As of now, A2 is not usable via the watch_register_interrupt_callback function. To enable an
+  *          external interrupt on pin A2, use the watch_register_extwake_callback function. This issue will be
+  *          addressed in a future revision of the watch library.
+  */
+void watch_register_interrupt_callback(const uint8_t pin, watch_cb_t callback, eic_interrupt_trigger trigger);
+
+/// @}