Fix incorrect delay when setting WS2812 (and similar) leds (#9302)

* Fix incorrect delay when setting WS2812 (and similar) leds

* Add documentation for WS2812_DELAY_MICROSECONDS

* Remove improper cast to uint8_t

Co-authored-by: Sergey Vlasov <sigprof@gmail.com>

* Remove unneeded cast to uint8_t and correct math

Co-authored-by: Sergey Vlasov <sigprof@gmail.com>

* microseconds -> µs

Co-authored-by: Ryan <fauxpark@gmail.com>

* Make documentation better match the spec sheet.

Co-authored-by: Ryan <fauxpark@gmail.com>

* Rename macro to match spec sheet

* Further correction to the delay maths for the SPI case.

Co-authored-by: Joel Challis <git@zvecr.com>

* Move ws2812_common.h to the drivers directory

* Revert "Further correction to the delay maths for the SPI case."

This reverts commit e61b56a2cfc7dfec9992a7a3af92afa50e5b8ec0.

* Remove ws2812_setleds_pin(); consolidate ws2812.h

Co-authored-by: Sergey Vlasov <sigprof@gmail.com>
Co-authored-by: Ryan <fauxpark@gmail.com>
Co-authored-by: Joel Challis <git@zvecr.com>

4 files changed, 5 insertions, 22 deletions

diff --git a/drivers/chibios/ws2812.c b/drivers/chibios/ws2812.c
index 2c2d9fb2d..5917b7f0e 100644
--- a/drivers/chibios/ws2812.c
+++ b/drivers/chibios/ws2812.c
@@ -51,7 +51,7 @@
 
 // The reset gap can be 6000 ns, but depending on the LED strip it may have to be increased
 // to values like 600000 ns. If it is too small, the pixels will show nothing most of the time.
-#define RES 10000  // Width of the low gap between bits to cause a frame to latch
+#define RES (1000 * WS2812_TRST_US) // Width of the low gap between bits to cause a frame to latch
 
 void sendByte(uint8_t byte) {
     // WS2812 protocol wants most significant bits first
diff --git a/drivers/chibios/ws2812.h b/drivers/chibios/ws2812.h
deleted file mode 100644
index 41c22a00b..000000000
--- a/drivers/chibios/ws2812.h
+++ /dev/null
@@ -1,16 +0,0 @@
-#pragma once
-
-#include "quantum/color.h"
-
-/* User Interface
- *
- * Input:
- *         ledarray:           An array of GRB data describing the LED colors
- *         number_of_leds:     The number of LEDs to write
- *
- * The functions will perform the following actions:
- *         - Set the data-out pin as output
- *         - Send out the LED data
- *         - Wait 50us to reset the LEDs
- */
-void ws2812_setleds(LED_TYPE *ledarray, uint16_t number_of_leds);
diff --git a/drivers/chibios/ws2812_pwm.c b/drivers/chibios/ws2812_pwm.c
index ba45d0042..7113db11e 100644
--- a/drivers/chibios/ws2812_pwm.c
+++ b/drivers/chibios/ws2812_pwm.c
@@ -53,11 +53,10 @@
 /**
  * @brief   Number of bit-periods to hold the data line low at the end of a frame
  *
- * The reset period for each frame must be at least 50 uS; so we add in 50 bit-times
- * of zeroes at the end. (50 bits)*(1.25 uS/bit) = 62.5 uS, which gives us some
- * slack in the timing requirements
+ * The reset period for each frame is defined in WS2812_TRST_US.
+ * Calculate the number of zeroes to add at the end assuming 1.25 uS/bit:
  */
-#define WS2812_RESET_BIT_N (50)
+#define WS2812_RESET_BIT_N (1000 * WS2812_TRST_US / 1250)
 #define WS2812_COLOR_BIT_N (RGBLED_NUM * 24)                   /**< Number of data bits */
 #define WS2812_BIT_N (WS2812_COLOR_BIT_N + WS2812_RESET_BIT_N) /**< Total number of bits in a frame */
 
diff --git a/drivers/chibios/ws2812_spi.c b/drivers/chibios/ws2812_spi.c
index 3bbada7fe..7a1d2f05d 100644
--- a/drivers/chibios/ws2812_spi.c
+++ b/drivers/chibios/ws2812_spi.c
@@ -36,7 +36,7 @@
 #define NB_COLORS 3
 #define BYTES_FOR_LED (BYTES_FOR_LED_BYTE * NB_COLORS)
 #define DATA_SIZE (BYTES_FOR_LED * RGBLED_NUM)
-#define RESET_SIZE 200
+#define RESET_SIZE (1000 * WS2812_TRST_US / (2 * 1250))
 #define PREAMBLE_SIZE 4
 
 static uint8_t txbuf[PREAMBLE_SIZE + DATA_SIZE + RESET_SIZE] = {0};