drivers/ws281x: added arm backend, leveraging the light_ws2812 package

drivers/ws281x/Makefile.dep

@@ -1,5 +1,5 @@
 # Actually |(periph_timer_poll and periph_gpio_ll), but that's too complex for FEATURES_REQUIRED_ANY to express
-FEATURES_REQUIRED_ANY += cpu_core_atmega|arch_esp32|arch_native|periph_timer_poll
+FEATURES_REQUIRED_ANY += cpu_core_atmega|arch_esp32|arch_native|periph_timer_poll|arch_arm
 
 ifeq (,$(filter ws281x_%,$(USEMODULE)))
   ifneq (,$(filter cpu_core_atmega,$(FEATURES_USED)))
@@ -15,6 +15,10 @@ ifeq (,$(filter ws281x_%,$(USEMODULE)))
   ifeq (-periph_timer_poll,$(filter ws281x_%,$(USEMODULE))-$(filter periph_timer_poll,$(FEATURES_USED)))
     USEMODULE += ws281x_timer_gpio_ll
   endif
+  ifneq (,$(filter arch_arm,$(FEATURES_USED)))
+    USEMODULE += ws281x_arm
+    USEPKG += light_ws2812
+  endif
 endif
 
 ifneq (,$(filter ws281x_atmega,$(USEMODULE)))

drivers/ws281x/arm.c

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2022 BISSELL Homecare, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     drivers_ws281x
+ *
+ * @{
+ *
+ * @file
+ * @brief       Implementation of `ws281x_write_buffer()` for the ARM CPU
+ *
+ * @author      David VanKampen <[email protected]>
+ *
+ * @}
+ */
+#include <assert.h>
+#include <errno.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "ws281x.h"
+#include "ws281x_params.h"
+#include "ws281x_constants.h"
+
+#include "light_ws2812_cortex.h"
+
+void ws281x_write_buffer(ws281x_t *dev, const void *buf, size_t size)
+{
+    assert(dev);
+    ws2812_sendarray((uint8_t*)buf, size);
+}

drivers/ws281x/include/ws281x_backend.h

@@ -56,7 +56,14 @@ extern "C" {
  * @{
  */
 #ifdef MODULE_WS281X_TIMER_GPIO_LL
-#define WS281X_HAVE_INIT                    (1)
+#define WS281X_HAVE_INIT (1)
+/** @} */
+
+/**
+ * @name    Properties of the ARM backend.
+ * @{
+ */
+#ifdef MODULE_WS281X_ARM
 #endif
 /** @} */
 

examples/light_ws2812/main.c

@@ -30,7 +30,7 @@ int main(void)
 {
     puts("Generated RIOT application: 'light_ws2812'");
     random_init(SEED);
-    while(1) {
+    while (1) {
         for (uint8_t idx = 0; idx < NUM_LEDS; idx++) {
             leds[idx] = (uint8_t)random_uint32();
         }