diff options
| -rw-r--r-- | docs/ws2812_driver.md | 29 | ||||
| -rw-r--r-- | drivers/arm/ws2812_spi.c | 91 |
2 files changed, 118 insertions, 2 deletions
diff --git a/docs/ws2812_driver.md b/docs/ws2812_driver.md index 67481c458d..80b6948586 100644 --- a/docs/ws2812_driver.md +++ b/docs/ws2812_driver.md @@ -14,7 +14,7 @@ These LEDs are called "addressable" because instead of using a wire per color, e |----------|--------------------|--------------------| | bit bang | :heavy_check_mark: | :heavy_check_mark: | | I2C | :heavy_check_mark: | | -| SPI | | Soon™ | +| SPI | | :heavy_check_mark: | | PWM | | Soon™ | ## Driver configuration @@ -40,3 +40,30 @@ Configure the hardware via your config.h: #define WS2812_ADDRESS 0xb0 // default: 0xb0 #define WS2812_TIMEOUT 100 // default: 100 ``` + +### SPI +Targeting STM32 boards where WS2812 support is offloaded to an SPI hardware device. The advantage is that the use of DMA offloads processing of the WS2812 protocol from the MCU. `RGB_DI_PIN` for this driver is the configured SPI MOSI pin. Due to the nature of repurposing SPI to drive the LEDs, the other SPI pins, MISO and SCK, **must** remain unused. To configure it, add this to your rules.mk: + +```make +WS2812_DRIVER = spi +``` + +Configure the hardware via your config.h: +```c +#define WS2812_SPI SPID1 // default: SPID1 +#define WS2812_SPI_MOSI_PAL_MODE 5 // Pin "alternate function", see the respective datasheet for the appropriate values for your MCU. default: 5 +``` + +You must also turn on the SPI feature in your halconf.h and mcuconf.h + +#### Testing Notes + +While not an exhaustive list, the following table provides the scenarios that have been partially validated: + +| | SPI1 | SPI2 | SPI3 | +|-|-|-|-| +| f072 | ? | B15 :heavy_check_mark: | N/A | +| f103 | A7 :heavy_check_mark: | B15 :heavy_check_mark: | N/A | +| f303 | A7 :heavy_check_mark: B5 :heavy_check_mark: | B15 :heavy_check_mark: | B5 :heavy_check_mark: | + +*Other supported ChibiOS boards and/or pins may function, it will be highly chip and configuration dependent.*
\ No newline at end of file diff --git a/drivers/arm/ws2812_spi.c b/drivers/arm/ws2812_spi.c index 2094e50098..0e954ec506 100644 --- a/drivers/arm/ws2812_spi.c +++ b/drivers/arm/ws2812_spi.c @@ -1 +1,90 @@ -#error("NOT SUPPORTED")
\ No newline at end of file +#include "quantum.h" +#include "ws2812.h" + +/* Adapted from https://github.com/gamazeps/ws2812b-chibios-SPIDMA/ */ + +#ifdef RGBW +# error "RGBW not supported" +#endif + +// Define the spi your LEDs are plugged to here +#ifndef WS2812_SPI +# define WS2812_SPI SPID1 +#endif + +#ifndef WS2812_SPI_MOSI_PAL_MODE +# define WS2812_SPI_MOSI_PAL_MODE 5 +#endif + +#define BYTES_FOR_LED_BYTE 4 +#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 PREAMBLE_SIZE 4 + +static uint8_t txbuf[PREAMBLE_SIZE + DATA_SIZE + RESET_SIZE] = {0}; + +/* + * As the trick here is to use the SPI to send a huge pattern of 0 and 1 to + * the ws2812b protocol, we use this helper function to translate bytes into + * 0s and 1s for the LED (with the appropriate timing). + */ +static uint8_t get_protocol_eq(uint8_t data, int pos) { + uint8_t eq = 0; + if (data & (1 << (2 * (3 - pos)))) + eq = 0b1110; + else + eq = 0b1000; + if (data & (2 << (2 * (3 - pos)))) + eq += 0b11100000; + else + eq += 0b10000000; + return eq; +} + +static void set_led_color_rgb(LED_TYPE color, int pos) { + uint8_t* tx_start = &txbuf[PREAMBLE_SIZE]; + + for (int j = 0; j < 4; j++) tx_start[BYTES_FOR_LED * pos + j] = get_protocol_eq(color.g, j); + for (int j = 0; j < 4; j++) tx_start[BYTES_FOR_LED * pos + BYTES_FOR_LED_BYTE + j] = get_protocol_eq(color.r, j); + for (int j = 0; j < 4; j++) tx_start[BYTES_FOR_LED * pos + BYTES_FOR_LED_BYTE * 2 + j] = get_protocol_eq(color.b, j); +} + +void ws2812_init(void) { +#if defined(USE_GPIOV1) + palSetLineMode(RGB_DI_PIN, PAL_MODE_STM32_ALTERNATE_PUSHPULL); +#else + palSetLineMode(RGB_DI_PIN, PAL_MODE_ALTERNATE(WS2812_SPI_MOSI_PAL_MODE) | PAL_STM32_OTYPE_PUSHPULL); +#endif + + // TODO: more dynamic baudrate + static const SPIConfig spicfg = { + NULL, PAL_PORT(RGB_DI_PIN), PAL_PAD(RGB_DI_PIN), + SPI_CR1_BR_1 | SPI_CR1_BR_0 // baudrate : fpclk / 8 => 1tick is 0.32us (2.25 MHz) + }; + + spiAcquireBus(&WS2812_SPI); /* Acquire ownership of the bus. */ + spiStart(&WS2812_SPI, &spicfg); /* Setup transfer parameters. */ + spiSelect(&WS2812_SPI); /* Slave Select assertion. */ +} + +void ws2812_setleds(LED_TYPE* ledarray, uint16_t leds) { + static bool s_init = false; + if (!s_init) { + ws2812_init(); + s_init = true; + } + + for (uint8_t i = 0; i < leds; i++) { + set_led_color_rgb(ledarray[i], i); + } + + // Send async - each led takes ~0.03ms, 50 leds ~1.5ms, animations flushing faster than send will cause issues. + // Instead spiSend can be used to send synchronously (or the thread logic can be added back). +#ifdef WS2812_SPI_SYNC + spiSend(&WS2812_SPI, sizeof(txbuf) / sizeof(txbuf[0]), txbuf); +#else + spiStartSend(&WS2812_SPI, sizeof(txbuf) / sizeof(txbuf[0]), txbuf); +#endif +} |