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Elixir Cross Referencer

#
# Copyright (c) 2017 Linaro Limited
#
# SPDX-License-Identifier: Apache-2.0
#

# The following blog post is an excellent resource about pulse timing:
#
# https://wp.josh.com/2014/05/13/ws2812-neopixels-are-not-so-finicky-once-you-get-to-know-them/

menuconfig WS2812_STRIP
	bool "Enable WS2812 (and compatible) LED strip driver"
	depends on SPI
	help
		Enable LED strip driver for daisy chains of WS2812-ish
		(or WS2812B, WS2813, SK6812, or compatible) devices.
		These devices have a one-wire communications interface
		which encodes bits using pulses. Short pulses indicate
		zero bits, and long pulses indicate ones; refer to the
		chip datasheets for precise specifications. To implement
		this in a multitasking operating system, this driver
		generates the pulses using a SPI peripheral.

if WS2812_STRIP

config WS2812_STRIP_MAX_PIXELS
	int "Maximum number of pixels in a strip"
	default 12
	help
		Set this to the maximum number of pixels you need
		to control at once. There is an 8x memory penalty associated
		with each increment of this value, so it's worth optimizing.

config WS2812_STRIP_ONE_FRAME
	hex "SPI frame to shift out to signal a one bit"
	default 0x7c if SOC_SERIES_STM32F4X
	default 0x70 if SOC_FAMILY_NRF
	help
		When shifted out at the configured clock frequency,
		this must generate a pulse whose width fits within the chipset
		specifications for T1H, and whose interpulse timing meets low
		times. It is recommended that the first and last bits in the
		frame be zero; this "encourages" SPI IPs to leave MOSI low
		between frames.

config WS2812_STRIP_ZERO_FRAME
	hex "SPI frame to shift out to signal a zero bit"
	default 0x60 if SOC_SERIES_STM32F4X
	default 0x40 if SOC_FAMILY_NRF
	help
		When shifted out at the configured clock frequency,
		this must generate a pulse whose width fits within the chipset
		specifications for T0H, and whose interpulse timing meets low
		times. It is recommended that the first and last bits in the
		frame be zero; this "encourages" SPI IPs to leave MOSI low
		between frames.

# By default, we use GRBW [sic] (and ignore W).
comment "The following options determine channel data order on the wire."

config WS2812_RED_ORDER
	int "Order in which a red pixel should be shifted out"
	default 1
	range 0 3
	help
		If the red channel is shifted out first, specify 0.
		If second, specify 1, and so on.

config WS2812_GRN_ORDER
	int "Order in which a green pixel should be shifted out"
	default 0
	range 0 3
	help
		If the green channel is shifted out first, specify 0.
		If second, specify 1, and so on.

config WS2812_BLU_ORDER
	int "Order in which a blue pixel should be shifted out"
	default 2
	range 0 3
	help
		If the blue channel is shifted out first, specify 0.
		If second, specify 1, and so on.

config WS2812_HAS_WHITE_CHANNEL
	bool "Does the chip have a white channel on wire?"
	default y
	help
		If the chipset has a white channel, say y. White channels
		are not used by the driver, but must be declared if expected
		by the chip.

config WS2812_WHT_ORDER
	int "Order in which a white pixel should be shifted out"
	default 3
	range 0 3
	depends on WS2812_HAS_WHITE_CHANNEL
	help
		If the blue channel is shifted out first, specify 0.
		If second, specify 1, and so on.

endif # WS2812_STRIP