Add neopixel support

Author: hierophect

ports/esp32s2/Makefile

@@ -171,6 +171,7 @@ SRC_C += \
 	lib/utils/stdout_helpers.c \
 	lib/utils/sys_stdio_mphal.c \
 	peripherals/pins.c \
+	peripherals/rmt.c \
 	supervisor/shared/memory.c
 
 ifneq ($(USB),FALSE)

ports/esp32s2/boards/espressif_saola_1_wrover/mpconfigboard.h

@@ -29,4 +29,6 @@
 #define MICROPY_HW_BOARD_NAME       "Saola 1 w/Wrover"
 #define MICROPY_HW_MCU_NAME         "ESP32S2"
 
+#define MICROPY_HW_NEOPIXEL (&pin_GPIO18)
+
 #define AUTORESET_DELAY_MS 500

ports/esp32s2/boards/espressif_saola_1_wrover/pins.c

@@ -42,5 +42,7 @@ STATIC const mp_rom_map_elem_t board_global_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_IO44), MP_ROM_PTR(&pin_GPIO44) },
     { MP_ROM_QSTR(MP_QSTR_IO45), MP_ROM_PTR(&pin_GPIO45) },
     { MP_ROM_QSTR(MP_QSTR_IO46), MP_ROM_PTR(&pin_GPIO46) },
+
+    { MP_ROM_QSTR(MP_QSTR_NEOPIXEL), MP_ROM_PTR(&pin_GPIO18) },
 };
 MP_DEFINE_CONST_DICT(board_module_globals, board_global_dict_table);

ports/esp32s2/common-hal/microcontroller/Pin.c

@@ -26,12 +26,18 @@
  */
 
 #include "shared-bindings/microcontroller/Pin.h"
+#include "shared-bindings/digitalio/DigitalInOut.h"
+#include "supervisor/shared/rgb_led_status.h"
 
 #include "py/mphal.h"
 
 #include "esp-idf/components/driver/include/driver/gpio.h"
 #include "esp-idf/components/soc/include/hal/gpio_hal.h"
 
+#ifdef MICROPY_HW_NEOPIXEL
+bool neopixel_in_use;
+#endif
+
 STATIC uint32_t never_reset_pins[2];
 STATIC uint32_t in_use[2];
 
@@ -50,6 +56,14 @@ void common_hal_never_reset_pin(const mcu_pin_obj_t* pin) {
 void reset_pin_number(gpio_num_t pin_number) {
     never_reset_pins[pin_number / 32] &= ~(1 << pin_number % 32);
     in_use[pin_number / 32] &= ~(1 << pin_number % 32);
+
+    #ifdef MICROPY_HW_NEOPIXEL
+    if (pin_number == MICROPY_HW_NEOPIXEL->number) {
+        neopixel_in_use = false;
+        rgb_led_status_init();
+        return;
+    }
+    #endif
 }
 
 void common_hal_reset_pin(const mcu_pin_obj_t* pin) {
@@ -69,13 +83,28 @@ void reset_all_pins(void) {
     }
     in_use[0] = 0;
     in_use[1] = 0;
+
+    #ifdef MICROPY_HW_NEOPIXEL
+    neopixel_in_use = false;
+    #endif
 }
 
 void claim_pin(const mcu_pin_obj_t* pin) {
     in_use[pin->number / 32] |= (1 << pin->number % 32);
+    #ifdef MICROPY_HW_NEOPIXEL
+    if (pin == MICROPY_HW_NEOPIXEL) {
+        neopixel_in_use = true;
+    }
+    #endif
 }
 
 bool pin_number_is_free(gpio_num_t pin_number) {
+    #ifdef MICROPY_HW_NEOPIXEL
+    if (pin_number == MICROPY_HW_NEOPIXEL->number) {
+        return !neopixel_in_use;
+    }
+    #endif
+
     uint8_t offset = pin_number / 32;
     uint8_t mask = 1 << pin_number % 32;
     return (never_reset_pins[offset] & mask) == 0 && (in_use[offset] & mask) == 0;

ports/esp32s2/common-hal/microcontroller/Pin.h

@@ -34,6 +34,10 @@
 extern bool apa102_mosi_in_use;
 extern bool apa102_sck_in_use;
 
+#ifdef MICROPY_HW_NEOPIXEL
+extern bool neopixel_in_use;
+#endif
+
 void reset_all_pins(void);
 // reset_pin_number takes the pin number instead of the pointer so that objects don't
 // need to store a full pointer.

ports/esp32s2/common-hal/neopixel_write/__init__.c

@@ -3,7 +3,7 @@
  *
  * The MIT License (MIT)
  *
- * Copyright (c) 2018 hathach for Adafruit Industries
+ * Copyright (c) 2020 Lucian Copeland for Adafruit Industries
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -24,10 +24,101 @@
  * THE SOFTWARE.
  */
 
+/* Uses code from Espressif RGB LED Strip demo and drivers
+ * Copyright 2015-2020 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 "py/mphal.h"
 #include "shared-bindings/neopixel_write/__init__.h"
+#include "driver/rmt.h"
+#include "rmt.h"
+
+#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;
+
+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;
+}
 
 void common_hal_neopixel_write (const digitalio_digitalinout_obj_t* digitalinout, uint8_t *pixels, uint32_t numBytes) {
-    (void)digitalinout;
-    (void)numBytes;
+    // Reserve channel
+    uint8_t number = digitalinout->pin->number;
+    rmt_channel_t channel = esp32s2_peripherals_find_and_reserve_rmt();
+
+    // Configure Channel
+    rmt_config_t config = RMT_DEFAULT_CONFIG_TX(number, channel);
+    config.clk_div = 2; // set counter clock to 40MHz
+    rmt_config(&config);
+    rmt_driver_install(config.channel, 0, 0);
+
+    // Convert NS timings to ticks
+    uint32_t counter_clk_hz = 0;
+    if (rmt_get_counter_clock(config.channel, &counter_clk_hz) != ESP_OK) {
+        mp_raise_ValueError(translate("Could not retrieve clock"));
+    }
+    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);
+
+    // Initialize automatic timing translator
+    rmt_translator_init(config.channel, ws2812_rmt_adapter);
+
+    // Write and wait to finish
+    if(rmt_write_sample(config.channel, pixels, (size_t)numBytes, true) != ESP_OK) {
+        mp_raise_ValueError(translate("Input/output error"));
+    }
+    rmt_wait_tx_done(config.channel, pdMS_TO_TICKS(100));
+
+    // Free channel again
+    esp32s2_peripherals_free_rmt(config.channel);
 }

ports/esp32s2/common-hal/pulseio/PWMOut.c

@@ -3,8 +3,7 @@
  *
  * The MIT License (MIT)
  *
- * Copyright (c) 2019 Lucian Copeland for Adafruit Industries
- * Uses code from Micropython, Copyright (c) 2013-2016 Damien P. George
+ * Copyright (c) 2020 Lucian Copeland for Adafruit Industries
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal

ports/esp32s2/mpconfigport.mk

@@ -12,6 +12,8 @@ USB_SERIAL_NUMBER_LENGTH = 12
 # Longints can be implemented as mpz, as longlong, or not
 LONGINT_IMPL = MPZ
 
+CIRCUITPY_NEOPIXEL_WRITE = 1
+
 CIRCUITPY_FULL_BUILD = 0
 CIRCUITPY_ANALOGIO = 0
 CIRCUITPY_AUDIOBUSIO = 0

ports/esp32s2/peripherals/rmt.c

@@ -0,0 +1,45 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Lucian Copeland for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "rmt.h"
+#include "py/runtime.h"
+
+bool rmt_reserved_channels[RMT_CHANNEL_MAX];
+
+rmt_channel_t esp32s2_peripherals_find_and_reserve_rmt(void) {
+    for (size_t i = 0; i < RMT_CHANNEL_MAX; i++) {
+        if (!rmt_reserved_channels[i]) {
+            rmt_reserved_channels[i] = true;
+            return i;
+        }
+    }
+    mp_raise_RuntimeError(translate("All timers in use"));
+    return false;
+}
+
+void esp32s2_peripherals_free_rmt(rmt_channel_t chan) {
+    rmt_reserved_channels[chan] = false;
+}

ports/esp32s2/peripherals/rmt.h

@@ -0,0 +1,37 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Lucian Copeland for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_ESP32S2_PERIPHERALS_RMT_H
+#define MICROPY_INCLUDED_ESP32S2_PERIPHERALS_RMT_H
+
+#include "py/mphal.h"
+#include "driver/rmt.h"
+#include <stdint.h>
+
+rmt_channel_t esp32s2_peripherals_find_and_reserve_rmt(void);
+void esp32s2_peripherals_free_rmt(rmt_channel_t chan);
+
+#endif