Gracefully reset the gamepad module

deshipu · deshipu · commit 470a23d4c934 · 2017-10-22T00:50:58.000+02:00
If a soft reset happens while the gamepad module is scanning for button
presses, there is a moment when the pins get de-initialized, but the
gamepad module is still trying to read them, which ends in a crash.
We can avoid it by disabling scanning on reset.
diff --git a/atmel-samd/main.c b/atmel-samd/main.c
@@ -61,6 +61,7 @@
 #include "common-hal/pulseio/PWMOut.h"
 #include "common-hal/touchio/TouchIn.h"
 #include "common-hal/usb_hid/__init__.h"
+#include "shared-module/gamepad/__init__.h"
 
 #include "autoreload.h"
 #include "flash_api.h"
@@ -202,6 +203,9 @@ void reset_samd21(void) {
     pwmout_reset();
     analogin_reset();
 
+#ifdef CIRCUITPY_GAMEPAD_TICKS
+    gamepad_reset();
+#endif
 
     // TODO: move this to analogout_reset()
     // Wait for the DAC to sync then reset.
diff --git a/shared-module/gamepad/__init__.c b/shared-module/gamepad/__init__.c
@@ -49,3 +49,7 @@ void gamepad_tick(void) {
     gamepad_singleton->pressed |= gamepad_singleton->last & gamepad_current;
     gamepad_singleton->last = gamepad_current;
 }
+
+void gamepad_reset(void) {
+    gamepad_singleton = NULL;
+}
diff --git a/shared-module/gamepad/__init__.h b/shared-module/gamepad/__init__.h
@@ -28,5 +28,6 @@
 #define MICROPY_INCLUDED_GAMEPAD_H
 
 void gamepad_tick(void);
+void gamepad_reset(void);
 
 #endif  // MICROPY_INCLUDED_GAMEPAD_H

Original file line number	Diff line number	Diff line change
`@@ -49,3 +49,7 @@ void gamepad_tick(void) {`
`49`	`49`	`gamepad_singleton->pressed \|= gamepad_singleton->last & gamepad_current;`
`50`	`50`	`gamepad_singleton->last = gamepad_current;`
`51`	`51`	`}`
	`52`	`+`
	`53`	`+void gamepad_reset(void) {`
	`54`	`+ gamepad_singleton = NULL;`
	`55`	`+}`