esp8266: Replace esp.neopixel with machine.bitstream.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>

ports/esp8266/Makefile

@@ -91,10 +91,10 @@ SRC_C = \
 	lexerstr32.c \
 	uart.c \
 	esppwm.c \
-	espneopixel.c \
 	espapa102.c \
 	modpyb.c \
 	modmachine.c \
+	machine_bitstream.c \
 	machine_pin.c \
 	machine_pwm.c \
 	machine_rtc.c \

ports/esp8266/espneopixel.c

@@ -1,75 +0,0 @@
-// Original version from https://github.com/adafruit/Adafruit_NeoPixel
-// Modifications by dpgeorge to support auto-CPU-frequency detection
-
-// This is a mash-up of the Due show() code + insights from Michael Miller's
-// ESP8266 work for the NeoPixelBus library: github.com/Makuna/NeoPixelBus
-// Needs to be a separate .c file to enforce ICACHE_RAM_ATTR execution.
-
-#include "py/mpconfig.h"
-#if MICROPY_ESP8266_NEOPIXEL
-
-#include "c_types.h"
-#include "eagle_soc.h"
-#include "user_interface.h"
-#include "espneopixel.h"
-#include "esp_mphal.h"
-
-#define NEO_KHZ400 (1)
-
-void /*ICACHE_RAM_ATTR*/ esp_neopixel_write(uint8_t pin, uint8_t *pixels, uint32_t numBytes, bool is800KHz) {
-
-    uint8_t *p, *end, pix, mask;
-    uint32_t t, time0, time1, period, c, startTime, pinMask;
-
-    pinMask = 1 << pin;
-    p = pixels;
-    end = p + numBytes;
-    pix = *p++;
-    mask = 0x80;
-    startTime = 0;
-
-    uint32_t fcpu = system_get_cpu_freq() * 1000000;
-
-    #ifdef NEO_KHZ400
-    if (is800KHz) {
-    #endif
-    time0 = fcpu / 2857143;  // 0.35us
-    time1 = fcpu / 1250000;  // 0.8us
-    period = fcpu / 800000;  // 1.25us per bit
-    #ifdef NEO_KHZ400
-} else {   // 400 KHz bitstream
-    time0 = fcpu / 2000000;  // 0.5uS
-    time1 = fcpu / 833333;   // 1.2us
-    period = fcpu / 400000;  // 2.5us per bit
-}
-    #endif
-
-    uint32_t irq_state = mp_hal_quiet_timing_enter();
-    for (t = time0;; t = time0) {
-        if (pix & mask) {
-            t = time1;                                    // Bit high duration
-        }
-        while (((c = mp_hal_ticks_cpu()) - startTime) < period) {
-            ;                                               // Wait for bit start
-        }
-        GPIO_REG_WRITE(GPIO_OUT_W1TS_ADDRESS, pinMask);   // Set high
-        startTime = c;                                    // Save start time
-        while (((c = mp_hal_ticks_cpu()) - startTime) < t) {
-            ;                                               // Wait high duration
-        }
-        GPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, pinMask);   // Set low
-        if (!(mask >>= 1)) {                              // Next bit/byte
-            if (p >= end) {
-                break;
-            }
-            pix = *p++;
-            mask = 0x80;
-        }
-    }
-    while ((mp_hal_ticks_cpu() - startTime) < period) {
-        ;                                           // Wait for last bit
-    }
-    mp_hal_quiet_timing_exit(irq_state);
-}
-
-#endif // MICROPY_ESP8266_NEOPIXEL

ports/esp8266/espneopixel.h

@@ -1,6 +0,0 @@
-#ifndef MICROPY_INCLUDED_ESP8266_ESPNEOPIXEL_H
-#define MICROPY_INCLUDED_ESP8266_ESPNEOPIXEL_H
-
-void esp_neopixel_write(uint8_t pin, uint8_t *pixels, uint32_t numBytes, bool is800KHz);
-
-#endif // MICROPY_INCLUDED_ESP8266_ESPNEOPIXEL_H

ports/esp8266/machine_bitstream.c

@@ -0,0 +1,76 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2021 Jim Mussared
+ *
+ * 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.
+ */
+
+// This is slightly modified from the implementation in ports/esp32/machine_bitstream.c.
+
+#include "py/mpconfig.h"
+#include "py/mphal.h"
+
+#if MICROPY_PY_MACHINE_BITSTREAM
+
+#define NS_TICKS_OVERHEAD (8)
+
+void machine_bitstream_high_low(mp_hal_pin_obj_t pin, uint32_t *timing_ns, const uint8_t *buf, size_t len) {
+    uint32_t pin_mask = 1 << pin;
+
+    // Convert ns to cpu ticks [high_time_0, period_0, high_time_1, period_1].
+    uint32_t fcpu_mhz = system_get_cpu_freq();
+    for (size_t i = 0; i < 4; ++i) {
+        timing_ns[i] = fcpu_mhz * timing_ns[i] / 1000;
+        if (timing_ns[i] > NS_TICKS_OVERHEAD) {
+            timing_ns[i] -= NS_TICKS_OVERHEAD;
+        }
+        if (i % 2 == 1) {
+            // Convert low_time to period (i.e. add high_time).
+            timing_ns[i] += timing_ns[i - 1];
+        }
+    }
+
+    uint32_t irq_state = mp_hal_quiet_timing_enter();
+
+    for (size_t i = 0; i < len; ++i) {
+        uint8_t b = buf[i];
+        for (size_t j = 0; j < 8; ++j) {
+            GPIO_REG_WRITE(GPIO_OUT_W1TS_ADDRESS, pin_mask);
+            uint32_t start_ticks = mp_hal_ticks_cpu();
+            uint32_t *t = &timing_ns[b >> 6 & 2];
+            uint32_t end_ticks = start_ticks + t[0];
+            while (mp_hal_ticks_cpu() - start_ticks < t[0]) {
+                ;
+            }
+            GPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, pin_mask);
+            b <<= 1;
+            end_ticks += t[1];
+            while (mp_hal_ticks_cpu() - start_ticks < t[1]) {
+                ;
+            }
+        }
+    }
+
+    mp_hal_quiet_timing_exit(irq_state);
+}
+
+#endif // MICROPY_PY_MACHINE_BITSTREAM

ports/esp8266/modesp.c

@@ -36,7 +36,6 @@
 #include "user_interface.h"
 #include "mem.h"
 #include "ets_alt_task.h"
-#include "espneopixel.h"
 #include "espapa102.h"
 #include "modmachine.h"
 
@@ -199,16 +198,6 @@ STATIC mp_obj_t esp_check_fw(void) {
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_0(esp_check_fw_obj, esp_check_fw);
 
-
-STATIC mp_obj_t esp_neopixel_write_(mp_obj_t pin, mp_obj_t buf, mp_obj_t is800k) {
-    mp_buffer_info_t bufinfo;
-    mp_get_buffer_raise(buf, &bufinfo, MP_BUFFER_READ);
-    esp_neopixel_write(mp_obj_get_pin_obj(pin)->phys_port,
-        (uint8_t *)bufinfo.buf, bufinfo.len, mp_obj_is_true(is800k));
-    return mp_const_none;
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_3(esp_neopixel_write_obj, esp_neopixel_write_);
-
 #if MICROPY_ESP8266_APA102
 STATIC mp_obj_t esp_apa102_write_(mp_obj_t clockPin, mp_obj_t dataPin, mp_obj_t buf) {
     mp_buffer_info_t bufinfo;
@@ -363,9 +352,6 @@ STATIC const mp_rom_map_elem_t esp_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR_flash_erase), MP_ROM_PTR(&esp_flash_erase_obj) },
     { MP_ROM_QSTR(MP_QSTR_flash_size), MP_ROM_PTR(&esp_flash_size_obj) },
     { MP_ROM_QSTR(MP_QSTR_flash_user_start), MP_ROM_PTR(&esp_flash_user_start_obj) },
-    #if MICROPY_ESP8266_NEOPIXEL
-    { MP_ROM_QSTR(MP_QSTR_neopixel_write), MP_ROM_PTR(&esp_neopixel_write_obj) },
-    #endif
     #if MICROPY_ESP8266_APA102
     { MP_ROM_QSTR(MP_QSTR_apa102_write), MP_ROM_PTR(&esp_apa102_write_obj) },
     #endif

ports/esp8266/modmachine.c

@@ -35,6 +35,7 @@
 // This needs to be set before we include the RTOS headers
 #define USE_US_TIMER 1
 
+#include "extmod/machine_bitstream.h"
 #include "extmod/machine_mem.h"
 #include "extmod/machine_signal.h"
 #include "extmod/machine_pulse.h"
@@ -411,6 +412,10 @@ STATIC const mp_rom_map_elem_t machine_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR_disable_irq), MP_ROM_PTR(&machine_disable_irq_obj) },
     { MP_ROM_QSTR(MP_QSTR_enable_irq), MP_ROM_PTR(&machine_enable_irq_obj) },
 
+    #if MICROPY_PY_MACHINE_BITSTREAM
+    { MP_ROM_QSTR(MP_QSTR_bitstream), MP_ROM_PTR(&machine_bitstream_obj) },
+    #endif
+
     { MP_ROM_QSTR(MP_QSTR_time_pulse_us), MP_ROM_PTR(&machine_time_pulse_us_obj) },
 
     { MP_ROM_QSTR(MP_QSTR_RTC), MP_ROM_PTR(&pyb_rtc_type) },

ports/esp8266/modules/neopixel.py

@@ -1,7 +1,12 @@
-# NeoPixel driver for MicroPython on ESP8266
-# MIT license; Copyright (c) 2016 Damien P. George
+# NeoPixel driver for MicroPython
+# MIT license; Copyright (c) 2016 Damien P. George, 2021 Jim Mussared
 
-from esp import neopixel_write
+from micropython import const
+from machine import bitstream
+
+_BITSTREAM_TYPE_HIGH_LOW = const(0)
+_TIMING_WS2818_800 = (400, 850, 800, 450)
+_TIMING_WS2818_400 = (800, 1700, 1600, 900)
 
 
 class NeoPixel:
@@ -13,7 +18,11 @@ class NeoPixel:
         self.bpp = bpp
         self.buf = bytearray(n * bpp)
         self.pin.init(pin.OUT)
-        self.timing = timing
+        self.timing = (
+            (_TIMING_WS2818_800 if timing else _TIMING_WS2818_400)
+            if isinstance(timing, int)
+            else timing
+        )
 
     def __len__(self):
         return self.n
@@ -32,4 +41,4 @@ class NeoPixel:
             self[i] = color
 
     def write(self):
-        neopixel_write(self.pin, self.buf, self.timing)
+        bitstream(self.pin, _BITSTREAM_TYPE_HIGH_LOW, self.timing, self.buf)

ports/esp8266/mpconfigport.h

@@ -79,6 +79,7 @@
 #define MICROPY_PY_LWIP_SOCK_RAW    (1)
 #define MICROPY_PY_MACHINE          (1)
 #define MICROPY_PY_MACHINE_PIN_MAKE_NEW mp_pin_make_new
+#define MICROPY_PY_MACHINE_BITSTREAM (1)
 #define MICROPY_PY_MACHINE_PULSE    (1)
 #define MICROPY_PY_MACHINE_I2C      (1)
 #define MICROPY_PY_MACHINE_SPI      (1)
@@ -102,7 +103,6 @@
 #define MICROPY_FATFS_MAX_SS           (4096)
 #define MICROPY_FATFS_LFN_CODE_PAGE    437 /* 1=SFN/ANSI 437=LFN/U.S.(OEM) */
 #define MICROPY_ESP8266_APA102         (1)
-#define MICROPY_ESP8266_NEOPIXEL       (1)
 
 #define MICROPY_EVENT_POLL_HOOK {ets_event_poll();}
 #define MICROPY_VM_HOOK_COUNT (10)