diff options
Diffstat (limited to 'tinyusb/hw/bsp/esp32s3/components/led_strip/src/led_strip_rmt_ws2812.c')
-rwxr-xr-x | tinyusb/hw/bsp/esp32s3/components/led_strip/src/led_strip_rmt_ws2812.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/tinyusb/hw/bsp/esp32s3/components/led_strip/src/led_strip_rmt_ws2812.c b/tinyusb/hw/bsp/esp32s3/components/led_strip/src/led_strip_rmt_ws2812.c new file mode 100755 index 00000000..025d3c59 --- /dev/null +++ b/tinyusb/hw/bsp/esp32s3/components/led_strip/src/led_strip_rmt_ws2812.c @@ -0,0 +1,171 @@ +// Copyright 2019 Espressif Systems (Shanghai) PTE LTD +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +#include <stdlib.h> +#include <string.h> +#include <sys/cdefs.h> +#include "esp_log.h" +#include "esp_attr.h" +#include "led_strip.h" +#include "driver/rmt.h" + +static const char *TAG = "ws2812"; +#define STRIP_CHECK(a, str, goto_tag, ret_value, ...) \ + do \ + { \ + if (!(a)) \ + { \ + ESP_LOGE(TAG, "%s(%d): " str, __FUNCTION__, __LINE__, ##__VA_ARGS__); \ + ret = ret_value; \ + goto goto_tag; \ + } \ + } while (0) + +#define WS2812_T0H_NS (350) +#define WS2812_T0L_NS (1000) +#define WS2812_T1H_NS (1000) +#define WS2812_T1L_NS (350) +#define WS2812_RESET_US (280) + +static uint32_t ws2812_t0h_ticks = 0; +static uint32_t ws2812_t1h_ticks = 0; +static uint32_t ws2812_t0l_ticks = 0; +static uint32_t ws2812_t1l_ticks = 0; + +typedef struct { + led_strip_t parent; + rmt_channel_t rmt_channel; + uint32_t strip_len; + uint8_t buffer[0]; +} ws2812_t; + +/** + * @brief Conver RGB data to RMT format. + * + * @note For WS2812, R,G,B each contains 256 different choices (i.e. uint8_t) + * + * @param[in] src: source data, to converted to RMT format + * @param[in] dest: place where to store the convert result + * @param[in] src_size: size of source data + * @param[in] wanted_num: number of RMT items that want to get + * @param[out] translated_size: number of source data that got converted + * @param[out] item_num: number of RMT items which are converted from source data + */ +static void IRAM_ATTR ws2812_rmt_adapter(const void *src, rmt_item32_t *dest, size_t src_size, + size_t wanted_num, size_t *translated_size, size_t *item_num) +{ + if (src == NULL || dest == NULL) { + *translated_size = 0; + *item_num = 0; + return; + } + const rmt_item32_t bit0 = {{{ ws2812_t0h_ticks, 1, ws2812_t0l_ticks, 0 }}}; //Logical 0 + const rmt_item32_t bit1 = {{{ ws2812_t1h_ticks, 1, ws2812_t1l_ticks, 0 }}}; //Logical 1 + size_t size = 0; + size_t num = 0; + uint8_t *psrc = (uint8_t *)src; + rmt_item32_t *pdest = dest; + while (size < src_size && num < wanted_num) { + for (int i = 0; i < 8; i++) { + // MSB first + if (*psrc & (1 << (7 - i))) { + pdest->val = bit1.val; + } else { + pdest->val = bit0.val; + } + num++; + pdest++; + } + size++; + psrc++; + } + *translated_size = size; + *item_num = num; +} + +static esp_err_t ws2812_set_pixel(led_strip_t *strip, uint32_t index, uint32_t red, uint32_t green, uint32_t blue) +{ + esp_err_t ret = ESP_OK; + ws2812_t *ws2812 = __containerof(strip, ws2812_t, parent); + STRIP_CHECK(index < ws2812->strip_len, "index out of the maximum number of leds", err, ESP_ERR_INVALID_ARG); + uint32_t start = index * 3; + // In thr order of GRB + ws2812->buffer[start + 0] = green & 0xFF; + ws2812->buffer[start + 1] = red & 0xFF; + ws2812->buffer[start + 2] = blue & 0xFF; + return ESP_OK; +err: + return ret; +} + +static esp_err_t ws2812_refresh(led_strip_t *strip, uint32_t timeout_ms) +{ + esp_err_t ret = ESP_OK; + ws2812_t *ws2812 = __containerof(strip, ws2812_t, parent); + STRIP_CHECK(rmt_write_sample(ws2812->rmt_channel, ws2812->buffer, ws2812->strip_len * 3, true) == ESP_OK, + "transmit RMT samples failed", err, ESP_FAIL); + return rmt_wait_tx_done(ws2812->rmt_channel, pdMS_TO_TICKS(timeout_ms)); +err: + return ret; +} + +static esp_err_t ws2812_clear(led_strip_t *strip, uint32_t timeout_ms) +{ + ws2812_t *ws2812 = __containerof(strip, ws2812_t, parent); + // Write zero to turn off all leds + memset(ws2812->buffer, 0, ws2812->strip_len * 3); + return ws2812_refresh(strip, timeout_ms); +} + +static esp_err_t ws2812_del(led_strip_t *strip) +{ + ws2812_t *ws2812 = __containerof(strip, ws2812_t, parent); + free(ws2812); + return ESP_OK; +} + +led_strip_t *led_strip_new_rmt_ws2812(const led_strip_config_t *config) +{ + led_strip_t *ret = NULL; + STRIP_CHECK(config, "configuration can't be null", err, NULL); + + // 24 bits per led + uint32_t ws2812_size = sizeof(ws2812_t) + config->max_leds * 3; + ws2812_t *ws2812 = calloc(1, ws2812_size); + STRIP_CHECK(ws2812, "request memory for ws2812 failed", err, NULL); + + uint32_t counter_clk_hz = 0; + STRIP_CHECK(rmt_get_counter_clock((rmt_channel_t)config->dev, &counter_clk_hz) == ESP_OK, + "get rmt counter clock failed", err, NULL); + // ns -> ticks + float ratio = (float)counter_clk_hz / 1e9; + ws2812_t0h_ticks = (uint32_t)(ratio * WS2812_T0H_NS); + ws2812_t0l_ticks = (uint32_t)(ratio * WS2812_T0L_NS); + ws2812_t1h_ticks = (uint32_t)(ratio * WS2812_T1H_NS); + ws2812_t1l_ticks = (uint32_t)(ratio * WS2812_T1L_NS); + + // set ws2812 to rmt adapter + rmt_translator_init((rmt_channel_t)config->dev, ws2812_rmt_adapter); + + ws2812->rmt_channel = (rmt_channel_t)config->dev; + ws2812->strip_len = config->max_leds; + + ws2812->parent.set_pixel = ws2812_set_pixel; + ws2812->parent.refresh = ws2812_refresh; + ws2812->parent.clear = ws2812_clear; + ws2812->parent.del = ws2812_del; + + return &ws2812->parent; +err: + return ret; +} |