From 6d78cef999c67eb16c415a2fc0b94accf330fed1 Mon Sep 17 00:00:00 2001 From: Gunar Schorcht Date: Sun, 26 Mar 2023 18:34:25 +0200 Subject: [PATCH] drivers/ws281x: add ESP32x hardware support --- drivers/ws281x/Kconfig | 19 +++++++ drivers/ws281x/Makefile.dep | 13 +++++ drivers/ws281x/esp32.c | 110 +++++++++++++++++++++++++++++++++++- 3 files changed, 140 insertions(+), 2 deletions(-) diff --git a/drivers/ws281x/Kconfig b/drivers/ws281x/Kconfig index f197f2d34f..ef44ba5f5e 100644 --- a/drivers/ws281x/Kconfig +++ b/drivers/ws281x/Kconfig @@ -26,6 +26,25 @@ config MODULE_WS281X_ESP32 bool depends on HAS_ARCH_ESP32 +config MODULE_WS281X_ESP32_HW + bool "WS2812/SK6812 RGB LED uses ESP32x RMT" + depends on MODULE_WS281X_ESP32 && HAS_ESP_RMT + default y + help + The driver can use on ESP32x SoCs either the Remote Control (RMT) + peripheral or a bit-banging software implementation to generate the + RGB LED signal. Using the RMT peripheral requires more ROM and RAM but + does not use the CPU to generate the RGB LED signal. Disable this + option if saving ROM and RAM is required. + +config MODULE_WS281X_ESP32_SW + bool + depends on MODULE_WS281X_ESP32 + default y if !MODULE_WS281X_ESP32_HW + help + Use the bit-banging software implementation to generate the RGB LED + signal. + config HAVE_WS281X bool help diff --git a/drivers/ws281x/Makefile.dep b/drivers/ws281x/Makefile.dep index f3c0dbc74e..76ef1f0b32 100644 --- a/drivers/ws281x/Makefile.dep +++ b/drivers/ws281x/Makefile.dep @@ -15,3 +15,16 @@ endif ifneq (,$(filter ws281x_atmega,$(USEMODULE))) FEATURES_REQUIRED += cpu_core_atmega endif + +ifneq (,$(filter ws281x_esp32%,$(USEMODULE))) + FEATURES_REQUIRED += arch_esp32 + ifneq (,$(filter ws281x_esp32_sw,$(USEMODULE))) + USEMODULE += ws281x_esp32 + else + # use ESP32x RMT hardware implementation by default + FEATURES_REQUIRED += esp_rmt + USEMODULE += esp_idf_rmt + USEMODULE += ws281x_esp32 + USEMODULE += ws281x_esp32_hw + endif +endif diff --git a/drivers/ws281x/esp32.c b/drivers/ws281x/esp32.c index 328d1d5872..fa7ff56d30 100644 --- a/drivers/ws281x/esp32.c +++ b/drivers/ws281x/esp32.c @@ -1,5 +1,6 @@ /* * Copyright 2020 Christian Friedrich Coors + * 2023 Gunar Schorcht * * This file is subject to the terms and conditions of the GNU Lesser * General Public License v2.1. See the file LICENSE in the top level @@ -15,6 +16,7 @@ * @brief Implementation of `ws281x_write_buffer()` for the ESP32x CPU * * @author Christian Friedrich Coors + * @author Gunar Schorcht * * @} */ @@ -23,21 +25,71 @@ #include #include +#include "board.h" +#include "log.h" +#include "periph_cpu.h" + #include "ws281x.h" #include "ws281x_params.h" #include "ws281x_constants.h" -#include "periph_cpu.h" #include "esp_private/esp_clk.h" #include "hal/cpu_hal.h" #include "soc/rtc.h" +#ifdef MODULE_WS281X_ESP32_HW +#include "esp_intr_alloc.h" +#include "driver/rmt.h" +#include "hal/rmt_types.h" +#include "hal/rmt_ll.h" +#include "soc/rmt_struct.h" +#endif + #define ENABLE_DEBUG 0 #include "debug.h" +#ifdef MODULE_WS281X_ESP32_HW + +static uint32_t _ws281x_one_on; +static uint32_t _ws281x_one_off; +static uint32_t _ws281x_zero_on; +static uint32_t _ws281x_zero_off; + +static uint8_t _rmt_channel(ws281x_t *dev) +{ + for (unsigned i = 0; i < RMT_CH_NUMOF; i++) { + if (rmt_channel_config[i].gpio == dev->params.pin) { + return rmt_channel_config[i].channel; + } + } + assert(0); +} +#endif + void ws281x_write_buffer(ws281x_t *dev, const void *buf, size_t size) { assert(dev); + +#ifdef MODULE_WS281X_ESP32_HW + /* determine used RMT channel from configured GPIO */ + uint8_t channel = _rmt_channel(dev); + + /* determine the current clock frequency */ + uint32_t freq; + if (rmt_get_counter_clock(channel, &freq) != ESP_OK) { + LOG_ERROR("[ws281x_esp32] Could not get RMT counter clock\n"); + return; + } + + /* compute phase times used in ws2812_rmt_adapter once rmt_write_sample is called */ + uint32_t total_cycles = freq / (NS_PER_SEC / WS281X_T_DATA_NS); + _ws281x_one_on = freq / (NS_PER_SEC / WS281X_T_DATA_ONE_NS); + _ws281x_one_off = total_cycles - _ws281x_one_on; + _ws281x_zero_on = freq / (NS_PER_SEC / WS281X_T_DATA_ZERO_NS); + _ws281x_zero_off = total_cycles - _ws281x_zero_on; + + rmt_write_sample(channel, (const uint8_t *)buf, size, false); +#else const uint8_t *pos = buf; const uint8_t *end = pos + size; @@ -87,8 +139,45 @@ void ws281x_write_buffer(ws281x_t *dev, const void *buf, size_t size) /* final LOW phase */ current_wait = cpu_hal_get_cycle_count(); /* end of final LOW phase */ +#endif } +#ifdef MODULE_WS281X_ESP32_HW +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 = {{{ _ws281x_zero_on, 1, _ws281x_zero_off, 0 }}}; + const rmt_item32_t bit1 = {{{ _ws281x_one_on, 1, _ws281x_one_off, 0 }}}; + + size_t size = 0; + size_t num = 0; + uint8_t *psrc = (uint8_t *)src; + + while ((size < src_size) && (num < wanted_num)) { + uint8_t data = *psrc; + for (uint8_t cnt = 8; cnt > 0; cnt--) { + dest->val = (data & 0b10000000) ? bit1.val : bit0.val; + dest++; + num++; + data <<= 1; + } + size++; + psrc++; + } + *translated_size = size; + *item_num = num; +} +#endif + int ws281x_init(ws281x_t *dev, const ws281x_params_t *params) { if (!dev || !params || !params->buf) { @@ -98,9 +187,26 @@ int ws281x_init(ws281x_t *dev, const ws281x_params_t *params) memset(dev, 0, sizeof(ws281x_t)); dev->params = *params; +#ifdef MODULE_WS281X_ESP32_HW + static_assert(RMT_CH_NUMOF <= RMT_CH_NUMOF_MAX, + "[ws281x_esp32] RMT configuration problem"); + + /* determine used RMT channel from configured GPIO */ + uint8_t channel = _rmt_channel(dev); + + rmt_config_t cfg = RMT_DEFAULT_CONFIG_TX(params->pin, channel); + cfg.clk_div = 2; + + if ((rmt_config(&cfg) != ESP_OK) || + (rmt_driver_install(channel, 0, 0) != ESP_OK) || + (rmt_translator_init(channel, ws2812_rmt_adapter) != ESP_OK)) { + LOG_ERROR("[ws281x_esp32] RMT initialization failed\n"); + return -EIO; + } +#else if (gpio_init(dev->params.pin, GPIO_OUT)) { return -EIO; } - +#endif return 0; }