Fixes to memory check handling, split out switch handling to allow separate initialization

src/modules/px4iofirmware/px4io.c

@@ -228,23 +228,42 @@ user_start(int argc, char *argv[])
 	/* initialize PWM limit lib */
 	pwm_limit_init(&pwm_limit);
 
-	/* not enough memory, lock down */
-	if (minfo.mxordblk < 500) {
+	/*
+	 *    P O L I C E    L I G H T S
+	 *
+	 * Not enough memory, lock down.
+	 *
+	 * We might need to allocate mixers later, and this will
+	 * ensure that a developer doing a change will notice
+	 * that he just burned the remaining RAM with static
+	 * allocations. We don't want him to be able to
+	 * get past that point. This needs to be clearly
+	 * documented in the dev guide.
+         *
+	 */
+	if (minfo.mxordblk < 600) {
+
 		lowsyslog("ERR: not enough MEM");
 		bool phase = false;
 
-		if (phase) {
-			LED_AMBER(true);
-			LED_BLUE(false);
-		} else {
-			LED_AMBER(false);
-			LED_BLUE(true);
-		}
+		while (true) {
 
-		phase = !phase;
-		up_udelay(300000);
+			if (phase) {
+				LED_AMBER(true);
+				LED_BLUE(false);
+			} else {
+				LED_AMBER(false);
+				LED_BLUE(true);
+			}
+			up_udelay(250000);
+
+			phase = !phase;
+		}
 	}
 
+	/* Start the failsafe led init */
+	failsafe_led_init();
+
 	/*
 	 * Run everything in a tight loop.
 	 */

src/modules/px4iofirmware/px4io.h

@@ -184,6 +184,7 @@ extern void	mixer_handle_text(const void *buffer, size_t length);
  * Safety switch/LED.
  */
 extern void	safety_init(void);
+extern void	failsafe_led_init(void);
 
 /**
  * FMU communications

src/modules/px4iofirmware/safety.c

@@ -84,7 +84,11 @@ safety_init(void)
 {
 	/* arrange for the button handler to be called at 10Hz */
 	hrt_call_every(&arming_call, 1000, 100000, safety_check_button, NULL);
+}
 
+void
+failsafe_led_init(void)
+{
 	/* arrange for the failsafe blinker to be called at 8Hz */
 	hrt_call_every(&failsafe_call, 1000, 125000, failsafe_blink, NULL);
 }
@@ -165,8 +169,8 @@ failsafe_blink(void *arg)
 	/* indicate that a serious initialisation error occured */
 	if (!(r_status_flags & PX4IO_P_STATUS_FLAGS_INIT_OK)) {
 		LED_AMBER(true);
-	    return;
-    }
+		return;
+	}
 
 	static bool failsafe = false;