flight/pios/stm32f30x/pios_ws2811.c

   1 /**
   2  ******************************************************************************
   3  *
   4  * @file       pios_ws2811.c
   5  * @author     The LibrePilot Project, http://www.librepilot.org Copyright (C) 2017.
   6  * @brief      A driver for ws2811 rgb led controller.
   7  *             this is a port of the CleanFlight/BetaFlight implementation.
   8  * @see        The GNU Public License (GPL) Version 3
   9  *
  10  *****************************************************************************/
  11 /*
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 3 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  19  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with this program; if not, write to the Free Software Foundation, Inc.,
  24  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  25  */
  26
  27 #include "pios.h"
  28 #include "pios_ws2811.h"
  29 #include "pios_ws2811_cfg.h"
  30
  31 #define WS2811_BITS_PER_LED        24
  32 // for 50us delay
  33 #define WS2811_DELAY_BUFFER_LENGTH 42
  34
  35 #define WS2811_DATA_BUFFER_SIZE    (WS2811_BITS_PER_LED * PIOS_WS2811_NUMLEDS)
  36 // number of bytes needed is #LEDs * 24 bytes + 42 trailing bytes)
  37 #define WS2811_DMA_BUFFER_SIZE     (WS2811_DATA_BUFFER_SIZE + WS2811_DELAY_BUFFER_LENGTH)
  38
  39 #define WS2811_TIMER_HZ            24000000
  40 #define WS2811_TIMER_PERIOD        29
  41 // timer compare value for logical 1
  42 #define BIT_COMPARE_1              17
  43 // timer compare value for logical 0
  44 #define BIT_COMPARE_0              9
  45
  46 #define PIOS_WS2811_MAGIC          0x00281100
  47
  48 struct pios_ws2811_dev {
  49     uint32_t magic;
  50     const struct pios_ws2811_cfg *config;
  51     uint8_t  dma_buffer[WS2811_DMA_BUFFER_SIZE];
  52     bool     dma_active;
  53 };
  54
  55 struct pios_ws2811_dev *ws2811_dev;
  56
  57 void PIOS_WS2811_Init(uint32_t *dev_id, const struct pios_ws2811_cfg *ws2811_cfg)
  58 {
  59     if (ws2811_dev) {
  60         return;
  61     }
  62
  63     ws2811_dev = (struct pios_ws2811_dev *)pios_malloc(sizeof(*ws2811_dev));
  64
  65     PIOS_Assert(ws2811_dev);
  66
  67     memset(ws2811_dev, 0, sizeof(*ws2811_dev));
  68
  69     ws2811_dev->magic  = PIOS_WS2811_MAGIC;
  70     ws2811_dev->config = ws2811_cfg;
  71
  72
  73     TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
  74     TIM_OCInitTypeDef TIM_OCInitStructure;
  75     DMA_InitTypeDef DMA_InitStructure;
  76
  77     GPIO_Init(ws2811_cfg->pin.gpio, (GPIO_InitTypeDef *)&ws2811_cfg->pin.init);
  78
  79     GPIO_PinAFConfig(ws2811_cfg->pin.gpio, ws2811_cfg->pin.pin_source, ws2811_cfg->remap);
  80
  81     /* Compute the prescaler value */
  82     uint16_t prescalerValue = (uint16_t)(SystemCoreClock / WS2811_TIMER_HZ) - 1;
  83     /* Time base configuration */
  84     TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
  85     TIM_TimeBaseStructure.TIM_Period        = WS2811_TIMER_PERIOD; // 800kHz
  86     TIM_TimeBaseStructure.TIM_Prescaler     = prescalerValue;
  87     TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  88     TIM_TimeBaseStructure.TIM_CounterMode   = TIM_CounterMode_Up;
  89     TIM_TimeBaseInit(ws2811_cfg->timer, &TIM_TimeBaseStructure);
  90
  91     /* PWM1 Mode configuration: Channel1 */
  92     TIM_OCStructInit(&TIM_OCInitStructure);
  93     TIM_OCInitStructure.TIM_OCMode      = TIM_OCMode_PWM1;
  94     TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  95     TIM_OCInitStructure.TIM_Pulse       = 0;
  96     TIM_OCInitStructure.TIM_OCPolarity  = TIM_OCPolarity_High;
  97
  98     switch (ws2811_cfg->timer_chan) {
  99     case TIM_Channel_1:
 100         TIM_OC1Init(ws2811_cfg->timer, &TIM_OCInitStructure);
 101         TIM_OC1PreloadConfig(ws2811_cfg->timer, TIM_OCPreload_Enable);
 102         break;
 103     case TIM_Channel_2:
 104         TIM_OC2Init(ws2811_cfg->timer, &TIM_OCInitStructure);
 105         TIM_OC2PreloadConfig(ws2811_cfg->timer, TIM_OCPreload_Enable);
 106         break;
 107     case TIM_Channel_3:
 108         TIM_OC3Init(ws2811_cfg->timer, &TIM_OCInitStructure);
 109         TIM_OC3PreloadConfig(ws2811_cfg->timer, TIM_OCPreload_Enable);
 110         break;
 111     case TIM_Channel_4:
 112         TIM_OC4Init(ws2811_cfg->timer, &TIM_OCInitStructure);
 113         TIM_OC4PreloadConfig(ws2811_cfg->timer, TIM_OCPreload_Enable);
 114         break;
 115     }
 116
 117
 118     TIM_CtrlPWMOutputs(ws2811_cfg->timer, ENABLE);
 119
 120     /* configure DMA */
 121     // NVIC setup here
 122     NVIC_InitTypeDef NVIC_InitStructure;
 123
 124     NVIC_InitStructure.NVIC_IRQChannel    = ws2811_cfg->dma_irqn;
 125     NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = PIOS_IRQ_PRIO_LOW;
 126     NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
 127     NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
 128     NVIC_Init(&NVIC_InitStructure);
 129
 130
 131     DMA_DeInit(ws2811_cfg->dma_chan);
 132
 133     DMA_StructInit(&DMA_InitStructure);
 134     DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&ws2811_cfg->timer->CCR1 + ws2811_cfg->timer_chan;
 135     DMA_InitStructure.DMA_MemoryBaseAddr     = (uint32_t)ws2811_dev->dma_buffer;
 136     DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
 137     DMA_InitStructure.DMA_BufferSize         = WS2811_DMA_BUFFER_SIZE;
 138     DMA_InitStructure.DMA_PeripheralInc      = DMA_PeripheralInc_Disable;
 139     DMA_InitStructure.DMA_MemoryInc          = DMA_MemoryInc_Enable;
 140     DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
 141     DMA_InitStructure.DMA_MemoryDataSize     = DMA_MemoryDataSize_Byte;
 142     DMA_InitStructure.DMA_Mode     = DMA_Mode_Normal;
 143     DMA_InitStructure.DMA_Priority = DMA_Priority_High;
 144     DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
 145
 146     DMA_Init(ws2811_cfg->dma_chan, &DMA_InitStructure);
 147
 148     TIM_DMACmd(ws2811_cfg->timer, ws2811_cfg->timer_dma_source, ENABLE);
 149
 150     DMA_ITConfig(ws2811_cfg->dma_chan, DMA_IT_TC, ENABLE);
 151
 152     *dev_id = (uint32_t)ws2811_dev;
 153 }
 154
 155 void PIOS_WS2811_DMA_irq_handler()
 156 {
 157     if (!ws2811_dev) {
 158         return;
 159     }
 160
 161     if (DMA_GetITStatus(ws2811_dev->config->dma_tcif)) {
 162         ws2811_dev->dma_active = false;
 163         DMA_Cmd(ws2811_dev->config->dma_chan, DISABLE);
 164
 165         DMA_ClearITPendingBit(ws2811_dev->config->dma_tcif);
 166     }
 167 }
 168
 169
 170 /**
 171  * Set a led color
 172  * @param c color
 173  * @param led led number
 174  * @param update Perform an update after changing led color
 175  */
 176 void PIOS_WS2811_setColorRGB(Color_t c, uint8_t led, bool update)
 177 {
 178     if (!ws2811_dev || (led >= PIOS_WS2811_NUMLEDS)) {
 179         return;
 180     }
 181
 182     int offset   = led * WS2811_BITS_PER_LED;
 183
 184     uint32_t grb = (c.G << 16) | (c.R << 8) | (c.B);
 185
 186     for (int bit = (WS2811_BITS_PER_LED - 1); bit >= 0; --bit) {
 187         ws2811_dev->dma_buffer[offset++] = (grb & (1 << bit)) ? BIT_COMPARE_1 : BIT_COMPARE_0;
 188     }
 189
 190     if (update) {
 191         PIOS_WS2811_Update();
 192     }
 193 }
 194
 195 void PIOS_WS2811_Update()
 196 {
 197     if (!ws2811_dev || ws2811_dev->dma_active) {
 198         return;
 199     }
 200
 201     ws2811_dev->dma_active = true;
 202
 203     DMA_SetCurrDataCounter(ws2811_dev->config->dma_chan, WS2811_DMA_BUFFER_SIZE); // load number of bytes to be transferred
 204     TIM_SetCounter(ws2811_dev->config->timer, 0);
 205     TIM_Cmd(ws2811_dev->config->timer, ENABLE);
 206
 207     DMA_Cmd(ws2811_dev->config->dma_chan, ENABLE);
 208 }