add neopixel led strip driver for saola, make saola as an component

examples/device/board_test/CMakeLists.txt

@@ -2,13 +2,14 @@
 # CMakeLists in this exact order for cmake to work correctly
 cmake_minimum_required(VERSION 3.5)
 
-# example src directory
-set(EXTRA_COMPONENT_DIRS "src")
-
 # TOP is absolute path to root directory of TinyUSB git repo
 set(TOP "../../..")
 get_filename_component(TOP "${TOP}" REALPATH)
 
+# Add example src and bsp directories 
+set(EXTRA_COMPONENT_DIRS "src" "${TOP}/hw/bsp/esp32s2_saola_1")
+
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+set(SUPPORTED_TARGETS esp32s2)
 
 project(board_test)

examples/device/board_test/src/CMakeLists.txt

@@ -13,7 +13,3 @@ target_include_directories(${COMPONENT_TARGET} PUBLIC
   "${TOP}/hw"
   "${TOP}/src"
 )
-
-target_sources(${COMPONENT_TARGET} PUBLIC
-  "${TOP}/hw/bsp/esp32s2_saola_1/esp32s2_saola_1.c"
-)

hw/bsp/esp32s2_saola_1/CMakeLists.txt

@@ -0,0 +1,16 @@
+idf_component_register(SRCS "esp32s2_saola_1.c" "led_strip/src/led_strip_rmt_ws2812.c"
+                    INCLUDE_DIRS "led_strip/include"
+                    PRIV_REQUIRES "driver"
+                    REQUIRES freertos src)
+
+target_compile_options(${COMPONENT_TARGET} PUBLIC
+  "-DCFG_TUSB_MCU=OPT_MCU_ESP32S2"
+  "-DCFG_TUSB_OS=OPT_OS_FREERTOS"
+)
+
+idf_component_get_property( FREERTOS_ORIG_INCLUDE_PATH freertos ORIG_INCLUDE_PATH)
+target_include_directories(${COMPONENT_TARGET} PUBLIC
+  "${FREERTOS_ORIG_INCLUDE_PATH}"
+  "${TOP}/hw"
+  "${TOP}/src"  
+)

hw/bsp/esp32s2_saola_1/esp32s2_saola_1.c

@@ -24,26 +24,41 @@
  * This file is part of the TinyUSB stack.
  */
 
-#include "bsp/board.h"
+#include "../board.h"
 #include "driver/gpio.h"
 #include "hal/usb_hal.h"
 
+#include "driver/rmt.h"
+#include "led_strip/include/led_strip.h"
+
 //--------------------------------------------------------------------+
 // MACRO TYPEDEF CONSTANT ENUM DECLARATION
 //--------------------------------------------------------------------+
 
-// TODO use saola-1 on-board neopixel (WS2812)
-#define LED_PIN               21
+// Note: On the production version (v1.2) WS2812 is connected to GPIO 18,
+// however earlier revision v1.1 WS2812 is connected to GPIO 17
+//#define LED_PIN               18 // v1.2 and later
+#define LED_PIN               17 // v1.1
 
 #define BUTTON_PIN            0
 #define BUTTON_STATE_ACTIVE   0
 
+
+static led_strip_t *strip;
+
 // Initialize on-board peripherals : led, button, uart and USB
 void board_init(void)
 {
-  // LED
-  gpio_pad_select_gpio(LED_PIN);
-  gpio_set_direction(LED_PIN, GPIO_MODE_OUTPUT);
+  // WS2812 Neopixel driver with RMT peripheral
+  rmt_config_t config = RMT_DEFAULT_CONFIG_TX(LED_PIN, RMT_CHANNEL_0);
+  config.clk_div = 2; // set counter clock to 40MHz
+
+  rmt_config(&config);
+  rmt_driver_install(config.channel, 0, 0);
+
+  led_strip_config_t strip_config = LED_STRIP_DEFAULT_CONFIG(1, (led_strip_dev_t) config.channel);
+  strip = led_strip_new_rmt_ws2812(&strip_config);
+  strip->clear(strip, 100); // off led
 
   // Button
   gpio_pad_select_gpio(BUTTON_PIN);
@@ -60,7 +75,8 @@ void board_init(void)
 // Turn LED on or off
 void board_led_write(bool state)
 {
-  gpio_set_level(LED_PIN, state);
+  strip->set_pixel(strip, 0, (state ? 0x88 : 0x00), 0x00, 0x00);
+  strip->refresh(strip, 100);
 }
 
 // Get the current state of button

hw/bsp/esp32s2_saola_1/led_strip/include/led_strip.h

@@ -0,0 +1,126 @@
+// 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.
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "esp_err.h"
+
+/**
+* @brief LED Strip Type
+*
+*/
+typedef struct led_strip_s led_strip_t;
+
+/**
+* @brief LED Strip Device Type
+*
+*/
+typedef void *led_strip_dev_t;
+
+/**
+* @brief Declare of LED Strip Type
+*
+*/
+struct led_strip_s {
+    /**
+    * @brief Set RGB for a specific pixel
+    *
+    * @param strip: LED strip
+    * @param index: index of pixel to set
+    * @param red: red part of color
+    * @param green: green part of color
+    * @param blue: blue part of color
+    *
+    * @return
+    *      - ESP_OK: Set RGB for a specific pixel successfully
+    *      - ESP_ERR_INVALID_ARG: Set RGB for a specific pixel failed because of invalid parameters
+    *      - ESP_FAIL: Set RGB for a specific pixel failed because other error occurred
+    */
+    esp_err_t (*set_pixel)(led_strip_t *strip, uint32_t index, uint32_t red, uint32_t green, uint32_t blue);
+
+    /**
+    * @brief Refresh memory colors to LEDs
+    *
+    * @param strip: LED strip
+    * @param timeout_ms: timeout value for refreshing task
+    *
+    * @return
+    *      - ESP_OK: Refresh successfully
+    *      - ESP_ERR_TIMEOUT: Refresh failed because of timeout
+    *      - ESP_FAIL: Refresh failed because some other error occurred
+    *
+    * @note:
+    *      After updating the LED colors in the memory, a following invocation of this API is needed to flush colors to strip.
+    */
+    esp_err_t (*refresh)(led_strip_t *strip, uint32_t timeout_ms);
+
+    /**
+    * @brief Clear LED strip (turn off all LEDs)
+    *
+    * @param strip: LED strip
+    * @param timeout_ms: timeout value for clearing task
+    *
+    * @return
+    *      - ESP_OK: Clear LEDs successfully
+    *      - ESP_ERR_TIMEOUT: Clear LEDs failed because of timeout
+    *      - ESP_FAIL: Clear LEDs failed because some other error occurred
+    */
+    esp_err_t (*clear)(led_strip_t *strip, uint32_t timeout_ms);
+
+    /**
+    * @brief Free LED strip resources
+    *
+    * @param strip: LED strip
+    *
+    * @return
+    *      - ESP_OK: Free resources successfully
+    *      - ESP_FAIL: Free resources failed because error occurred
+    */
+    esp_err_t (*del)(led_strip_t *strip);
+};
+
+/**
+* @brief LED Strip Configuration Type
+*
+*/
+typedef struct {
+    uint32_t max_leds;   /*!< Maximum LEDs in a single strip */
+    led_strip_dev_t dev; /*!< LED strip device (e.g. RMT channel, PWM channel, etc) */
+} led_strip_config_t;
+
+/**
+ * @brief Default configuration for LED strip
+ *
+ */
+#define LED_STRIP_DEFAULT_CONFIG(number, dev_hdl) \
+    {                                             \
+        .max_leds = number,                       \
+        .dev = dev_hdl,                           \
+    }
+
+/**
+* @brief Install a new ws2812 driver (based on RMT peripheral)
+*
+* @param config: LED strip configuration
+* @return
+*      LED strip instance or NULL
+*/
+led_strip_t *led_strip_new_rmt_ws2812(const led_strip_config_t *config);
+
+#ifdef __cplusplus
+}
+#endif

hw/bsp/esp32s2_saola_1/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;
+}