Update docs

docs/apa102_driver.md

@@ -26,20 +26,51 @@ Add the following to your `config.h`:
 
 ## API :id=api
 
-### `void apa102_setleds(rgb_led_t *start_led, uint16_t num_leds)`
+### `void apa102_init(void)` :id=api-apa102-init
 
-Send RGB data to the APA102 LED chain.
+Initialize the LED driver. This function should be called first.
 
-#### Arguments :id=api-apa102-setleds-arguments
+---
+
+### `void apa102_set_color(uint16_t index, uint8_t red, uint8_t green, uint8_t blue)` :id=api-apa102-set-color
+
+Set the color of a single LED. This function does not immediately update the LEDs; call `apa102_flush()` after you are finished.
+
+#### Arguments :id=api-apa102-set-color-arguments
+
+ - `uint16_t index`  
+   The LED index in the APA102 chain.
+ - `uint8_t red`  
+   The red value to set.
+ - `uint8_t green`  
+   The green value to set.
+ - `uint8_t blue`  
+   The blue value to set.
+
+---
+
+### `void apa102_set_color_all(uint8_t red, uint8_t green, uint8_t blue)` :id=api-apa102-set-color-all
+
+Set the color of all LEDs.
+
+#### Arguments :id=api-apa102-set-color-all-arguments
+
+ - `uint8_t red`  
+   The red value to set.
+ - `uint8_t green`  
+   The green value to set.
+ - `uint8_t blue`  
+   The blue value to set.
+
+---
+
+### `void apa102_flush(void)` :id=api-apa102-flush
 
- - `rgb_led_t *start_led`  
-   A pointer to the LED array.
- - `uint16_t num_leds`  
-   The length of the LED array.
+Flush the PWM values to the LED chain.
 
 ---
 
-### `void apa102_set_brightness(uint8_t brightness)`
+### `void apa102_set_brightness(uint8_t brightness)` :id=api-apa102-set-brightness
 
 Set the global brightness.