From 72b3d5188b4b672104f830cc1315d678f2f2cc4c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?King=20K=C3=A9vin?= <kingkevin@cuvoodoo.info>
Date: Sat, 16 Apr 2016 12:12:47 +0200
Subject: [PATCH] don't block on led transmission

---
 lib/led_ws2812b.c | 7 ++++---
 lib/led_ws2812b.h | 6 ++++--
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/lib/led_ws2812b.c b/lib/led_ws2812b.c
index 7d08781..8515e3d 100644
--- a/lib/led_ws2812b.c
+++ b/lib/led_ws2812b.c
@@ -104,10 +104,10 @@ void ws2812b_set_rgb(uint16_t led, uint8_t red, uint8_t green, uint8_t blue)
 	}
 }
 
-void ws2812b_transmit(void)
+bool ws2812b_transmit(void)
 {
-	while (transmit_flag) { // wait for previous transmission to complete
-		__WFI();
+	if (transmit_flag) { // a transmission is already ongoing
+		return false;
 	}
 	transmit_flag = true; // remember transmission started
 	dma_set_memory_address(WS2812B_DMA, WS2812B_DMA_CH, (uint32_t)ws2812b_data);
@@ -119,6 +119,7 @@ void ws2812b_transmit(void)
 
 	timer_set_counter(WS2812B_TIMER, 0); // reset timer counter fro clean clock
 	timer_enable_counter(WS2812B_TIMER); // start timer to generate clock
+	return true;
 }
 
 void ws2812b_setup(void)
diff --git a/lib/led_ws2812b.h b/lib/led_ws2812b.h
index b936a9b..5c61ff2 100644
--- a/lib/led_ws2812b.h
+++ b/lib/led_ws2812b.h
@@ -33,5 +33,7 @@ void ws2812b_setup(void);
  *  @note transmission needs to be done separately
  */
 void ws2812b_set_rgb(uint16_t led, uint8_t red, uint8_t green, uint8_t blue);
-/** @brief transmit color values to WS2812b LEDs */
-void ws2812b_transmit(void);
+/** @brief transmit color values to WS2812b LEDs
+ *  @return true if transmission started, false if another transmission is already ongoing
+ */
+bool ws2812b_transmit(void);