Add driver that based on RPI-PICO's PIO feature for ws2812.
This driver can handle WS2812 or compatible LED strips.
The single PIO node can handle up to 4 strips.
Any pins that can be configured for PIO can be used for strips.
I verified the samples/driver/led_ws2812 sample
working with WS2812(144 pcs) led strip using following patches.
- samples/drivers/led_ws2812/boards/rpi_pico.overlay
```
/ {
aliases {
led-strip = &ws2812;
};
};
&pinctrl {
ws2812_pio0_default: ws2812_pio0_default {
ws2812 {
pinmux = <PIO0_P21>;
};
};
};
&pio0 {
status = "okay";
pio-ws2812 {
compatible = "worldsemi,ws2812-rpi_pico-pio";
status = "okay";
pinctrl-0 = <&ws2812_pio0_default>;
pinctrl-names = "default";
bit-waveform = <3>, <3>, <4>;
ws2812: ws2812 {
status = "okay";
output-pin = <21>;
chain-length = <144>;
color-mapping = <LED_COLOR_ID_GREEN
LED_COLOR_ID_RED
LED_COLOR_ID_BLUE>;
reset-delay = <280>;
frequency = <800000>;
};
};
};
```
- samples/drivers/led_ws2812/boards/rpi_pico.conf
```
CONFIG_WS2812_STRIP_RPI_PICO_PIO=y
```
Signed-off-by: TOKITA Hiroshi <tokita.hiroshi@gmail.com>
6699d4d4f9