diff options
Diffstat (limited to 'platforms/chibios/drivers/ws2812_pwm.c')
| -rw-r--r-- | platforms/chibios/drivers/ws2812_pwm.c | 311 | 
1 files changed, 311 insertions, 0 deletions
| diff --git a/platforms/chibios/drivers/ws2812_pwm.c b/platforms/chibios/drivers/ws2812_pwm.c new file mode 100644 index 0000000000..e6af55b6b3 --- /dev/null +++ b/platforms/chibios/drivers/ws2812_pwm.c @@ -0,0 +1,311 @@ +#include "ws2812.h" +#include "quantum.h" +#include <hal.h> + +/* Adapted from https://github.com/joewa/WS2812-LED-Driver_ChibiOS/ */ + +#ifdef RGBW +#    error "RGBW not supported" +#endif + +#ifndef WS2812_PWM_DRIVER +#    define WS2812_PWM_DRIVER PWMD2  // TIMx +#endif +#ifndef WS2812_PWM_CHANNEL +#    define WS2812_PWM_CHANNEL 2  // Channel +#endif +#ifndef WS2812_PWM_PAL_MODE +#    define WS2812_PWM_PAL_MODE 2  // DI Pin's alternate function value +#endif +#ifndef WS2812_DMA_STREAM +#    define WS2812_DMA_STREAM STM32_DMA1_STREAM2  // DMA Stream for TIMx_UP +#endif +#ifndef WS2812_DMA_CHANNEL +#    define WS2812_DMA_CHANNEL 2  // DMA Channel for TIMx_UP +#endif +#if (STM32_DMA_SUPPORTS_DMAMUX == TRUE) && !defined(WS2812_DMAMUX_ID) +#    error "please consult your MCU's datasheet and specify in your config.h: #define WS2812_DMAMUX_ID STM32_DMAMUX1_TIM?_UP" +#endif + +#ifndef WS2812_PWM_COMPLEMENTARY_OUTPUT +#    define WS2812_PWM_OUTPUT_MODE PWM_OUTPUT_ACTIVE_HIGH +#else +#    if !STM32_PWM_USE_ADVANCED +#        error "WS2812_PWM_COMPLEMENTARY_OUTPUT requires STM32_PWM_USE_ADVANCED == TRUE" +#    endif +#    define WS2812_PWM_OUTPUT_MODE PWM_COMPLEMENTARY_OUTPUT_ACTIVE_HIGH +#endif + +// Push Pull or Open Drain Configuration +// Default Push Pull +#ifndef WS2812_EXTERNAL_PULLUP +#    if defined(USE_GPIOV1) +#        define WS2812_OUTPUT_MODE PAL_MODE_STM32_ALTERNATE_PUSHPULL +#    else +#        define WS2812_OUTPUT_MODE PAL_MODE_ALTERNATE(WS2812_PWM_PAL_MODE) | PAL_STM32_OTYPE_PUSHPULL | PAL_STM32_OSPEED_HIGHEST | PAL_STM32_PUPDR_FLOATING +#    endif +#else +#    if defined(USE_GPIOV1) +#        define WS2812_OUTPUT_MODE PAL_MODE_STM32_ALTERNATE_OPENDRAIN +#    else +#        define WS2812_OUTPUT_MODE PAL_MODE_ALTERNATE(WS2812_PWM_PAL_MODE) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_OSPEED_HIGHEST | PAL_STM32_PUPDR_FLOATING +#    endif +#endif + +#ifndef WS2812_PWM_TARGET_PERIOD +//#    define WS2812_PWM_TARGET_PERIOD 800000 // Original code is 800k...? +#    define WS2812_PWM_TARGET_PERIOD 80000  // TODO: work out why 10x less on f303/f4x1 +#endif + +/* --- PRIVATE CONSTANTS ---------------------------------------------------- */ + +#define WS2812_PWM_FREQUENCY (STM32_SYSCLK / 2)                             /**< Clock frequency of PWM, must be valid with respect to system clock! */ +#define WS2812_PWM_PERIOD (WS2812_PWM_FREQUENCY / WS2812_PWM_TARGET_PERIOD) /**< Clock period in ticks. 1 / 800kHz = 1.25 uS (as per datasheet) */ + +/** + * @brief   Number of bit-periods to hold the data line low at the end of a frame + * + * 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 (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 */ + +/** + * @brief   High period for a zero, in ticks + * + * Per the datasheet: + * WS2812: + * - T0H: 200 nS to 500 nS, inclusive + * - T0L: 650 nS to 950 nS, inclusive + * WS2812B: + * - T0H: 200 nS to 500 nS, inclusive + * - T0L: 750 nS to 1050 nS, inclusive + * + * The duty cycle is calculated for a high period of 350 nS. + */ +#define WS2812_DUTYCYCLE_0 (WS2812_PWM_FREQUENCY / (1000000000 / 350)) + +/** + * @brief   High period for a one, in ticks + * + * Per the datasheet: + * WS2812: + * - T1H: 550 nS to 850 nS, inclusive + * - T1L: 450 nS to 750 nS, inclusive + * WS2812B: + * - T1H: 750 nS to 1050 nS, inclusive + * - T1L: 200 nS to 500 nS, inclusive + * + * The duty cycle is calculated for a high period of 800 nS. + * This is in the middle of the specifications of the WS2812 and WS2812B. + */ +#define WS2812_DUTYCYCLE_1 (WS2812_PWM_FREQUENCY / (1000000000 / 800)) + +/* --- PRIVATE MACROS ------------------------------------------------------- */ + +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given bit + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] byte:                 The byte number [0, 2] + * @param[in] bit:                  The bit number [0, 7] + * + * @return                          The bit index + */ +#define WS2812_BIT(led, byte, bit) (24 * (led) + 8 * (byte) + (7 - (bit))) + +#if (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_GRB) +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given red bit + * + * @note    The red byte is the middle byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit number [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_RED_BIT(led, bit) WS2812_BIT((led), 1, (bit)) + +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given green bit + * + * @note    The red byte is the first byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit number [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_GREEN_BIT(led, bit) WS2812_BIT((led), 0, (bit)) + +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given blue bit + * + * @note    The red byte is the last byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit index [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_BLUE_BIT(led, bit) WS2812_BIT((led), 2, (bit)) + +#elif (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_RGB) +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given red bit + * + * @note    The red byte is the middle byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit number [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_RED_BIT(led, bit) WS2812_BIT((led), 0, (bit)) + +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given green bit + * + * @note    The red byte is the first byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit number [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_GREEN_BIT(led, bit) WS2812_BIT((led), 1, (bit)) + +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given blue bit + * + * @note    The red byte is the last byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit index [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_BLUE_BIT(led, bit) WS2812_BIT((led), 2, (bit)) + +#elif (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_BGR) +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given red bit + * + * @note    The red byte is the middle byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit number [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_RED_BIT(led, bit) WS2812_BIT((led), 2, (bit)) + +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given green bit + * + * @note    The red byte is the first byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit number [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_GREEN_BIT(led, bit) WS2812_BIT((led), 1, (bit)) + +/** + * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given blue bit + * + * @note    The red byte is the last byte in the color packet + * + * @param[in] led:                  The led index [0, @ref RGBLED_NUM) + * @param[in] bit:                  The bit index [0, 7] + * + * @return                          The bit index + */ +#    define WS2812_BLUE_BIT(led, bit) WS2812_BIT((led), 0, (bit)) +#endif + +/* --- PRIVATE VARIABLES ---------------------------------------------------- */ + +static uint32_t ws2812_frame_buffer[WS2812_BIT_N + 1]; /**< Buffer for a frame */ + +/* --- PUBLIC FUNCTIONS ----------------------------------------------------- */ +/* + * Gedanke: Double-buffer type transactions: double buffer transfers using two memory pointers for +the memory (while the DMA is reading/writing from/to a buffer, the application can +write/read to/from the other buffer). + */ + +void ws2812_init(void) { +    // Initialize led frame buffer +    uint32_t i; +    for (i = 0; i < WS2812_COLOR_BIT_N; i++) ws2812_frame_buffer[i] = WS2812_DUTYCYCLE_0;      // All color bits are zero duty cycle +    for (i = 0; i < WS2812_RESET_BIT_N; i++) ws2812_frame_buffer[i + WS2812_COLOR_BIT_N] = 0;  // All reset bits are zero + +    palSetLineMode(RGB_DI_PIN, WS2812_OUTPUT_MODE); + +    // PWM Configuration +    //#pragma GCC diagnostic ignored "-Woverride-init"  // Turn off override-init warning for this struct. We use the overriding ability to set a "default" channel config +    static const PWMConfig ws2812_pwm_config = { +        .frequency = WS2812_PWM_FREQUENCY, +        .period    = WS2812_PWM_PERIOD,  // Mit dieser Periode wird UDE-Event erzeugt und ein neuer Wert (Länge WS2812_BIT_N) vom DMA ins CCR geschrieben +        .callback  = NULL, +        .channels = +            { +                [0 ... 3]                = {.mode = PWM_OUTPUT_DISABLED, .callback = NULL},     // Channels default to disabled +                [WS2812_PWM_CHANNEL - 1] = {.mode = WS2812_PWM_OUTPUT_MODE, .callback = NULL},  // Turn on the channel we care about +            }, +        .cr2  = 0, +        .dier = TIM_DIER_UDE,  // DMA on update event for next period +    }; +    //#pragma GCC diagnostic pop  // Restore command-line warning options + +    // Configure DMA +    // dmaInit(); // Joe added this +    dmaStreamAlloc(WS2812_DMA_STREAM - STM32_DMA_STREAM(0), 10, NULL, NULL); +    dmaStreamSetPeripheral(WS2812_DMA_STREAM, &(WS2812_PWM_DRIVER.tim->CCR[WS2812_PWM_CHANNEL - 1]));  // Ziel ist der An-Zeit im Cap-Comp-Register +    dmaStreamSetMemory0(WS2812_DMA_STREAM, ws2812_frame_buffer); +    dmaStreamSetTransactionSize(WS2812_DMA_STREAM, WS2812_BIT_N); +    dmaStreamSetMode(WS2812_DMA_STREAM, STM32_DMA_CR_CHSEL(WS2812_DMA_CHANNEL) | STM32_DMA_CR_DIR_M2P | STM32_DMA_CR_PSIZE_WORD | STM32_DMA_CR_MSIZE_WORD | STM32_DMA_CR_MINC | STM32_DMA_CR_CIRC | STM32_DMA_CR_PL(3)); +    // M2P: Memory 2 Periph; PL: Priority Level + +#if (STM32_DMA_SUPPORTS_DMAMUX == TRUE) +    // If the MCU has a DMAMUX we need to assign the correct resource +    dmaSetRequestSource(WS2812_DMA_STREAM, WS2812_DMAMUX_ID); +#endif + +    // Start DMA +    dmaStreamEnable(WS2812_DMA_STREAM); + +    // Configure PWM +    // NOTE: It's required that preload be enabled on the timer channel CCR register. This is currently enabled in the +    // ChibiOS driver code, so we don't have to do anything special to the timer. If we did, we'd have to start the timer, +    // disable counting, enable the channel, and then make whatever configuration changes we need. +    pwmStart(&WS2812_PWM_DRIVER, &ws2812_pwm_config); +    pwmEnableChannel(&WS2812_PWM_DRIVER, WS2812_PWM_CHANNEL - 1, 0);  // Initial period is 0; output will be low until first duty cycle is DMA'd in +} + +void ws2812_write_led(uint16_t led_number, uint8_t r, uint8_t g, uint8_t b) { +    // Write color to frame buffer +    for (uint8_t bit = 0; bit < 8; bit++) { +        ws2812_frame_buffer[WS2812_RED_BIT(led_number, bit)]   = ((r >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0; +        ws2812_frame_buffer[WS2812_GREEN_BIT(led_number, bit)] = ((g >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0; +        ws2812_frame_buffer[WS2812_BLUE_BIT(led_number, bit)]  = ((b >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0; +    } +} + +// Setleds for standard RGB +void ws2812_setleds(LED_TYPE* ledarray, uint16_t leds) { +    static bool s_init = false; +    if (!s_init) { +        ws2812_init(); +        s_init = true; +    } + +    for (uint16_t i = 0; i < leds; i++) { +        ws2812_write_led(i, ledarray[i].r, ledarray[i].g, ledarray[i].b); +    } +} | 
