Add a `gamepad` module for handling buttons in the background. (#295)

The `GamePad` singleton monitors buttons in the background to make sure a button press is never missed and debouncing happens consistently.

4 files changed, 174 insertions, 0 deletions

diff --git a/shared-module/gamepad/GamePad.c b/shared-module/gamepad/GamePad.c
new file mode 100644
index 000000000..3a2b8a3fe
--- /dev/null
+++ b/shared-module/gamepad/GamePad.c
@@ -0,0 +1,46 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Radomir Dopieralski for Adafruit Industries
+ *
+ * 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 <stdbool.h>
+
+#include "__init__.h"
+#include "GamePad.h"
+
+#include "shared-bindings/digitalio/Pull.h"
+#include "shared-bindings/digitalio/DigitalInOut.h"
+
+
+void gamepad_init(size_t n_pins, const mp_obj_t* pins) {
+    for (size_t i=0; i<8; ++i) {
+        gamepad_singleton->pins[i] = NULL;
+    }
+    for (size_t i=0; i<n_pins; ++i) {
+        digitalio_digitalinout_obj_t *pin = MP_OBJ_TO_PTR(pins[i]);
+        gamepad_singleton->pins[i] = pin;
+        common_hal_digitalio_digitalinout_switch_to_input(pin, PULL_UP);
+    }
+    gamepad_singleton->last = 0;
+}
diff --git a/shared-module/gamepad/GamePad.h b/shared-module/gamepad/GamePad.h
new file mode 100644
index 000000000..e5f709134
--- /dev/null
+++ b/shared-module/gamepad/GamePad.h
@@ -0,0 +1,45 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Radomir Dopieralski for Adafruit Industries
+ *
+ * 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.
+ */
+
+#ifndef MICROPY_INCLUDED_GAMEPAD_GAMEPAD_H
+#define MICROPY_INCLUDED_GAMEPAD_GAMEPAD_H
+
+#include <stdint.h>
+
+#include "shared-bindings/digitalio/DigitalInOut.h"
+
+typedef struct {
+    mp_obj_base_t base;
+    digitalio_digitalinout_obj_t* pins[8];
+    volatile uint8_t last;
+    volatile uint8_t pressed;
+} gamepad_obj_t;
+
+extern gamepad_obj_t* gamepad_singleton;
+
+void gamepad_init(size_t n_pins, const mp_obj_t* pins);
+
+#endif  // MICROPY_INCLUDED_GAMEPAD_GAMEPAD_H
diff --git a/shared-module/gamepad/__init__.c b/shared-module/gamepad/__init__.c
new file mode 100644
index 000000000..1aebf611d
--- /dev/null
+++ b/shared-module/gamepad/__init__.c
@@ -0,0 +1,51 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Radomir Dopieralski for Adafruit Industries
+ *
+ * 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 <stdbool.h>
+
+#include "__init__.h"
+#include "GamePad.h"
+
+#include "shared-bindings/digitalio/DigitalInOut.h"
+
+
+void gamepad_tick(void) {
+    if (!gamepad_singleton) {
+        return;
+    }
+    uint8_t gamepad_current = 0;
+    for (int i=0; i<8; ++i) {
+        digitalio_digitalinout_obj_t* pin = gamepad_singleton->pins[i];
+        if (!pin) {
+            break;
+        }
+        if (!common_hal_digitalio_digitalinout_get_value(pin)) {
+            gamepad_current |= 1<<i;
+        }
+    }
+    gamepad_singleton->pressed |= gamepad_singleton->last & gamepad_current;
+    gamepad_singleton->last = gamepad_current;
+}
diff --git a/shared-module/gamepad/__init__.h b/shared-module/gamepad/__init__.h
new file mode 100644
index 000000000..eacd72366
--- /dev/null
+++ b/shared-module/gamepad/__init__.h
@@ -0,0 +1,32 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Scott Shawcroft for Adafruit Industries
+ *
+ * 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.
+ */
+
+#ifndef MICROPY_INCLUDED_GAMEPAD_H
+#define MICROPY_INCLUDED_GAMEPAD_H
+
+void gamepad_tick(void);
+
+#endif  // MICROPY_INCLUDED_GAMEPAD_H