kopia lustrzana https://github.com/micropython/micropython
471 wiersze
17 KiB
C
471 wiersze
17 KiB
C
/*
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* This file is part of the MicroPython project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2021 Mike Teachman
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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// This file is never compiled standalone, it's included directly from
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// extmod/machine_i2s.c via MICROPY_PY_MACHINE_I2S_INCLUDEFILE.
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#include "py/mphal.h"
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#include "driver/i2s_std.h"
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#include "freertos/FreeRTOS.h"
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#include "freertos/task.h"
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#include "freertos/queue.h"
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#include "esp_task.h"
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// Notes on this port's specific implementation of I2S:
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// - a FreeRTOS task is created to implement the asynchronous background operations
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// - a FreeRTOS queue is used to transfer the supplied buffer to the background task
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// - all sample data transfers use DMA
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#define I2S_TASK_PRIORITY (ESP_TASK_PRIO_MIN + 1)
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#define I2S_TASK_STACK_SIZE (2048)
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#define DMA_BUF_LEN_IN_I2S_FRAMES (256)
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// The transform buffer is used with the readinto() method to bridge the opaque DMA memory on the ESP devices
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// with the app buffer. It facilitates audio sample transformations. e.g. 32-bits samples to 16-bit samples.
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// The size of 240 bytes is an engineering optimum that balances transfer performance with an acceptable use of heap space
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#define SIZEOF_TRANSFORM_BUFFER_IN_BYTES (240)
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typedef enum {
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I2S_TX_TRANSFER,
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I2S_RX_TRANSFER,
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} direction_t;
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typedef struct _non_blocking_descriptor_t {
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mp_buffer_info_t appbuf;
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mp_obj_t callback;
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direction_t direction;
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} non_blocking_descriptor_t;
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typedef enum {
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DMA_MEMORY_FULL,
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DMA_MEMORY_NOT_FULL,
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DMA_MEMORY_EMPTY,
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DMA_MEMORY_NOT_EMPTY,
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} dma_buffer_status_t;
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typedef struct _machine_i2s_obj_t {
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mp_obj_base_t base;
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i2s_port_t i2s_id;
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i2s_chan_handle_t i2s_chan_handle;
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mp_hal_pin_obj_t sck;
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mp_hal_pin_obj_t ws;
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mp_hal_pin_obj_t sd;
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i2s_dir_t mode;
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i2s_data_bit_width_t bits;
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format_t format;
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int32_t rate;
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int32_t ibuf;
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mp_obj_t callback_for_non_blocking;
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io_mode_t io_mode;
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bool is_deinit;
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uint8_t transform_buffer[SIZEOF_TRANSFORM_BUFFER_IN_BYTES];
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QueueHandle_t non_blocking_mode_queue;
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TaskHandle_t non_blocking_mode_task;
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dma_buffer_status_t dma_buffer_status;
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} machine_i2s_obj_t;
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static mp_obj_t machine_i2s_deinit(mp_obj_t self_in);
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// The frame map is used with the readinto() method to transform the audio sample data coming
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// from DMA memory (32-bit stereo, with the L and R channels reversed) to the format specified
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// in the I2S constructor. e.g. 16-bit mono
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static const int8_t i2s_frame_map[NUM_I2S_USER_FORMATS][I2S_RX_FRAME_SIZE_IN_BYTES] = {
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{ 2, 3, -1, -1, -1, -1, -1, -1 }, // Mono, 16-bits
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{ 0, 1, 2, 3, -1, -1, -1, -1 }, // Mono, 32-bits
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{ 2, 3, 6, 7, -1, -1, -1, -1 }, // Stereo, 16-bits
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{ 0, 1, 2, 3, 4, 5, 6, 7 }, // Stereo, 32-bits
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};
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void machine_i2s_init0() {
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for (i2s_port_t p = 0; p < I2S_NUM_AUTO; p++) {
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MP_STATE_PORT(machine_i2s_obj)[p] = NULL;
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}
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}
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static int8_t get_frame_mapping_index(i2s_data_bit_width_t bits, format_t format) {
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if (format == MONO) {
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if (bits == I2S_DATA_BIT_WIDTH_16BIT) {
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return 0;
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} else { // 32 bits
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return 1;
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}
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} else { // STEREO
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if (bits == I2S_DATA_BIT_WIDTH_16BIT) {
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return 2;
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} else { // 32 bits
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return 3;
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}
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}
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}
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static i2s_data_bit_width_t get_dma_bits(uint8_t mode, i2s_data_bit_width_t bits) {
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if (mode == MICROPY_PY_MACHINE_I2S_CONSTANT_TX) {
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return bits;
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} else { // Master Rx
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// read 32 bit samples for I2S hardware. e.g. MEMS microphones
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return I2S_DATA_BIT_WIDTH_32BIT;
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}
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}
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static i2s_slot_mode_t get_dma_format(uint8_t mode, format_t format) {
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if (mode == MICROPY_PY_MACHINE_I2S_CONSTANT_TX) {
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if (format == MONO) {
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return I2S_SLOT_MODE_MONO;
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} else { // STEREO
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return I2S_SLOT_MODE_STEREO;
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}
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} else { // Master Rx
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// read stereo frames for all I2S hardware
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return I2S_SLOT_MODE_STEREO;
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}
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}
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static uint32_t get_dma_buf_count(uint8_t mode, i2s_data_bit_width_t bits, format_t format, int32_t ibuf) {
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// calculate how many DMA buffers need to be allocated
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uint32_t dma_frame_size_in_bytes =
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(get_dma_bits(mode, bits) / 8) * (get_dma_format(mode, format) == I2S_SLOT_MODE_STEREO ? 2: 1);
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uint32_t dma_buf_count = ibuf / (DMA_BUF_LEN_IN_I2S_FRAMES * dma_frame_size_in_bytes);
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return dma_buf_count;
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}
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static uint32_t fill_appbuf_from_dma(machine_i2s_obj_t *self, mp_buffer_info_t *appbuf) {
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// copy audio samples from DMA memory to the app buffer
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// audio samples are read from DMA memory in chunks
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// loop, reading and copying chunks until the app buffer is filled
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// For asyncio mode, the loop will make an early exit if DMA memory becomes empty
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// Example:
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// a MicroPython I2S object is configured for 16-bit mono (2 bytes per audio sample).
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// For every frame coming from DMA (8 bytes), 2 bytes are "cherry picked" and
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// copied to the supplied app buffer.
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// Thus, for every 1 byte copied to the app buffer, 4 bytes are read from DMA memory.
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// If a 8kB app buffer is supplied, 32kB of audio samples is read from DMA memory.
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uint32_t a_index = 0;
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uint8_t *app_p = appbuf->buf;
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uint8_t appbuf_sample_size_in_bytes = (self->bits / 8) * (self->format == STEREO ? 2: 1);
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uint32_t num_bytes_needed_from_dma = appbuf->len * (I2S_RX_FRAME_SIZE_IN_BYTES / appbuf_sample_size_in_bytes);
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while (num_bytes_needed_from_dma) {
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size_t num_bytes_requested_from_dma = MIN(sizeof(self->transform_buffer), num_bytes_needed_from_dma);
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size_t num_bytes_received_from_dma = 0;
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TickType_t delay;
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if (self->io_mode == ASYNCIO) {
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delay = 0; // stop i2s_channel_read() operation if DMA memory becomes empty
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} else {
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delay = portMAX_DELAY; // block until supplied buffer is filled
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}
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esp_err_t ret = i2s_channel_read(
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self->i2s_chan_handle,
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self->transform_buffer,
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num_bytes_requested_from_dma,
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&num_bytes_received_from_dma,
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delay);
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// i2s_channel_read returns ESP_ERR_TIMEOUT when buffer cannot be filled by the timeout delay.
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if ((self->io_mode != ASYNCIO) ||
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((self->io_mode == ASYNCIO) && (ret != ESP_ERR_TIMEOUT))) {
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check_esp_err(ret);
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}
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// process the transform buffer one frame at a time.
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// copy selected bytes from the transform buffer into the user supplied appbuf.
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// Example:
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// a MicroPython I2S object is configured for 16-bit mono. This configuration associates to
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// a frame map index of 0 = { 6, 7, -1, -1, -1, -1, -1, -1 } in the i2s_frame_map array
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// This mapping indicates:
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// appbuf[x+0] = frame[6]
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// appbuf[x+1] = frame[7]
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// frame bytes 0-5 are not used
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uint32_t t_index = 0;
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uint8_t f_index = get_frame_mapping_index(self->bits, self->format);
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while (t_index < num_bytes_received_from_dma) {
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uint8_t *transform_p = self->transform_buffer + t_index;
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for (uint8_t i = 0; i < I2S_RX_FRAME_SIZE_IN_BYTES; i++) {
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int8_t t_to_a_mapping = i2s_frame_map[f_index][i];
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if (t_to_a_mapping != -1) {
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*app_p++ = transform_p[t_to_a_mapping];
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a_index++;
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}
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t_index++;
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}
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}
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num_bytes_needed_from_dma -= num_bytes_received_from_dma;
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if ((self->io_mode == ASYNCIO) && (num_bytes_received_from_dma < num_bytes_requested_from_dma)) {
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// Unable to fill the entire app buffer from DMA memory. This indicates all DMA RX buffers are empty.
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self->dma_buffer_status = DMA_MEMORY_EMPTY;
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break;
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}
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}
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return a_index;
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}
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static size_t copy_appbuf_to_dma(machine_i2s_obj_t *self, mp_buffer_info_t *appbuf) {
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size_t num_bytes_written = 0;
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TickType_t delay;
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if (self->io_mode == ASYNCIO) {
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delay = 0; // stop i2s_channel_write() operation if DMA memory becomes full
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} else {
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delay = portMAX_DELAY; // block until supplied buffer is emptied
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}
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esp_err_t ret = i2s_channel_write(self->i2s_chan_handle, appbuf->buf, appbuf->len, &num_bytes_written, delay);
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// i2s_channel_write returns ESP_ERR_TIMEOUT when buffer cannot be emptied by the timeout delay.
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if ((self->io_mode != ASYNCIO) ||
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((self->io_mode == ASYNCIO) && (ret != ESP_ERR_TIMEOUT))) {
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check_esp_err(ret);
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}
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if ((self->io_mode == ASYNCIO) && (num_bytes_written < appbuf->len)) {
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// Unable to empty the entire app buffer into DMA memory. This indicates all DMA TX buffers are full.
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self->dma_buffer_status = DMA_MEMORY_FULL;
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}
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return num_bytes_written;
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}
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// FreeRTOS task used for non-blocking mode
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static void task_for_non_blocking_mode(void *self_in) {
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machine_i2s_obj_t *self = (machine_i2s_obj_t *)self_in;
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non_blocking_descriptor_t descriptor;
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for (;;) {
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if (xQueueReceive(self->non_blocking_mode_queue, &descriptor, portMAX_DELAY)) {
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if (descriptor.direction == I2S_TX_TRANSFER) {
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copy_appbuf_to_dma(self, &descriptor.appbuf);
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} else { // RX
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fill_appbuf_from_dma(self, &descriptor.appbuf);
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}
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mp_sched_schedule(descriptor.callback, MP_OBJ_FROM_PTR(self));
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}
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}
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}
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// callback indicating that a DMA buffer was just filled with samples received from an I2S port
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static IRAM_ATTR bool i2s_rx_recv_callback(i2s_chan_handle_t handle, i2s_event_data_t *event, void *self_in) {
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machine_i2s_obj_t *self = (machine_i2s_obj_t *)self_in;
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self->dma_buffer_status = DMA_MEMORY_NOT_EMPTY;
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return false;
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}
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// callback indicating that samples in a DMA buffer were just transmitted to an I2S port
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static IRAM_ATTR bool i2s_tx_sent_callback(i2s_chan_handle_t handle, i2s_event_data_t *event, void *self_in) {
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machine_i2s_obj_t *self = (machine_i2s_obj_t *)self_in;
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self->dma_buffer_status = DMA_MEMORY_NOT_FULL;
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return false;
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}
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i2s_event_callbacks_t i2s_callbacks = {
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.on_recv = i2s_rx_recv_callback,
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.on_recv_q_ovf = NULL,
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.on_sent = i2s_tx_sent_callback,
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.on_send_q_ovf = NULL,
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};
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i2s_event_callbacks_t i2s_callbacks_null = {
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.on_recv = NULL,
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.on_recv_q_ovf = NULL,
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.on_sent = NULL,
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.on_send_q_ovf = NULL,
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};
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static void mp_machine_i2s_init_helper(machine_i2s_obj_t *self, mp_arg_val_t *args) {
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// are Pins valid?
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int8_t sck = args[ARG_sck].u_obj == MP_OBJ_NULL ? -1 : machine_pin_get_id(args[ARG_sck].u_obj);
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int8_t ws = args[ARG_ws].u_obj == MP_OBJ_NULL ? -1 : machine_pin_get_id(args[ARG_ws].u_obj);
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int8_t sd = args[ARG_sd].u_obj == MP_OBJ_NULL ? -1 : machine_pin_get_id(args[ARG_sd].u_obj);
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// is Mode valid?
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int8_t mode = args[ARG_mode].u_int;
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if ((mode != (MICROPY_PY_MACHINE_I2S_CONSTANT_RX)) &&
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(mode != (MICROPY_PY_MACHINE_I2S_CONSTANT_TX))) {
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mp_raise_ValueError(MP_ERROR_TEXT("invalid mode"));
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}
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// is Bits valid?
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i2s_data_bit_width_t bits = args[ARG_bits].u_int;
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if ((bits != I2S_DATA_BIT_WIDTH_16BIT) &&
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(bits != I2S_DATA_BIT_WIDTH_32BIT)) {
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mp_raise_ValueError(MP_ERROR_TEXT("invalid bits"));
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}
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// is Format valid?
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format_t format = args[ARG_format].u_int;
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if ((format != STEREO) &&
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(format != MONO)) {
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mp_raise_ValueError(MP_ERROR_TEXT("invalid format"));
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}
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// is Rate valid?
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// Not checked: ESP-IDF I2S API does not indicate a valid range for sample rate
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// is Ibuf valid?
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// Not checked: ESP-IDF I2S API will return error if requested buffer size exceeds available memory
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self->sck = sck;
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self->ws = ws;
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self->sd = sd;
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self->mode = mode;
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self->bits = bits;
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self->format = format;
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self->rate = args[ARG_rate].u_int;
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self->ibuf = args[ARG_ibuf].u_int;
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self->callback_for_non_blocking = MP_OBJ_NULL;
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self->non_blocking_mode_queue = NULL;
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self->non_blocking_mode_task = NULL;
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self->io_mode = BLOCKING;
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self->is_deinit = false;
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if (mode == MICROPY_PY_MACHINE_I2S_CONSTANT_TX) {
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self->dma_buffer_status = DMA_MEMORY_NOT_FULL;
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} else { // rx
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self->dma_buffer_status = DMA_MEMORY_NOT_EMPTY;
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}
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i2s_chan_config_t chan_config = I2S_CHANNEL_DEFAULT_CONFIG(self->i2s_id, I2S_ROLE_MASTER);
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chan_config.dma_desc_num = get_dma_buf_count(mode, bits, format, self->ibuf);
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chan_config.dma_frame_num = DMA_BUF_LEN_IN_I2S_FRAMES;
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chan_config.auto_clear = true;
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if (mode == MICROPY_PY_MACHINE_I2S_CONSTANT_TX) {
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ESP_ERROR_CHECK(i2s_new_channel(&chan_config, &self->i2s_chan_handle, NULL));
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} else { // rx
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ESP_ERROR_CHECK(i2s_new_channel(&chan_config, NULL, &self->i2s_chan_handle));
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}
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i2s_std_slot_config_t slot_cfg = I2S_STD_PHILIPS_SLOT_DEFAULT_CONFIG(get_dma_bits(mode, bits), get_dma_format(mode, format));
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slot_cfg.slot_mask = I2S_STD_SLOT_BOTH;
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i2s_std_config_t std_cfg = {
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.clk_cfg = I2S_STD_CLK_DEFAULT_CONFIG(self->rate),
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.slot_cfg = slot_cfg,
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.gpio_cfg = {
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.mclk = I2S_GPIO_UNUSED,
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.bclk = self->sck,
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.ws = self->ws,
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.invert_flags = {
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.mclk_inv = false,
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.bclk_inv = false,
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.ws_inv = false,
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},
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},
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};
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if (mode == MICROPY_PY_MACHINE_I2S_CONSTANT_TX) {
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std_cfg.gpio_cfg.dout = self->sd;
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std_cfg.gpio_cfg.din = I2S_GPIO_UNUSED;
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} else { // rx
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std_cfg.gpio_cfg.dout = I2S_GPIO_UNUSED;
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std_cfg.gpio_cfg.din = self->sd;
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}
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ESP_ERROR_CHECK(i2s_channel_init_std_mode(self->i2s_chan_handle, &std_cfg));
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ESP_ERROR_CHECK(i2s_channel_register_event_callback(self->i2s_chan_handle, &i2s_callbacks, self));
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ESP_ERROR_CHECK(i2s_channel_enable(self->i2s_chan_handle));
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}
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static machine_i2s_obj_t *mp_machine_i2s_make_new_instance(mp_int_t i2s_id) {
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if (i2s_id < 0 || i2s_id >= I2S_NUM_AUTO) {
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mp_raise_ValueError(MP_ERROR_TEXT("invalid id"));
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}
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machine_i2s_obj_t *self;
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if (MP_STATE_PORT(machine_i2s_obj)[i2s_id] == NULL) {
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self = mp_obj_malloc_with_finaliser(machine_i2s_obj_t, &machine_i2s_type);
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MP_STATE_PORT(machine_i2s_obj)[i2s_id] = self;
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self->i2s_id = i2s_id;
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} else {
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self = MP_STATE_PORT(machine_i2s_obj)[i2s_id];
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machine_i2s_deinit(self);
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}
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return self;
|
|
}
|
|
|
|
static void mp_machine_i2s_deinit(machine_i2s_obj_t *self) {
|
|
if (!self->is_deinit) {
|
|
ESP_ERROR_CHECK(i2s_channel_disable(self->i2s_chan_handle));
|
|
ESP_ERROR_CHECK(i2s_channel_register_event_callback(self->i2s_chan_handle, &i2s_callbacks_null, self));
|
|
ESP_ERROR_CHECK(i2s_del_channel(self->i2s_chan_handle));
|
|
|
|
if (self->non_blocking_mode_task != NULL) {
|
|
vTaskDelete(self->non_blocking_mode_task);
|
|
self->non_blocking_mode_task = NULL;
|
|
}
|
|
|
|
if (self->non_blocking_mode_queue != NULL) {
|
|
vQueueDelete(self->non_blocking_mode_queue);
|
|
self->non_blocking_mode_queue = NULL;
|
|
}
|
|
self->is_deinit = true;
|
|
}
|
|
}
|
|
|
|
static void mp_machine_i2s_irq_update(machine_i2s_obj_t *self) {
|
|
if (self->io_mode == NON_BLOCKING) {
|
|
// create a queue linking the MicroPython task to a FreeRTOS task
|
|
// that manages the non blocking mode of operation
|
|
self->non_blocking_mode_queue = xQueueCreate(1, sizeof(non_blocking_descriptor_t));
|
|
|
|
// non-blocking mode requires a background FreeRTOS task
|
|
if (xTaskCreatePinnedToCore(
|
|
task_for_non_blocking_mode,
|
|
"i2s_non_blocking",
|
|
I2S_TASK_STACK_SIZE,
|
|
self,
|
|
I2S_TASK_PRIORITY,
|
|
(TaskHandle_t *)&self->non_blocking_mode_task,
|
|
MP_TASK_COREID) != pdPASS) {
|
|
|
|
mp_raise_msg(&mp_type_RuntimeError, MP_ERROR_TEXT("failed to create I2S task"));
|
|
}
|
|
} else {
|
|
if (self->non_blocking_mode_task != NULL) {
|
|
vTaskDelete(self->non_blocking_mode_task);
|
|
self->non_blocking_mode_task = NULL;
|
|
}
|
|
|
|
if (self->non_blocking_mode_queue != NULL) {
|
|
vQueueDelete(self->non_blocking_mode_queue);
|
|
self->non_blocking_mode_queue = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
MP_REGISTER_ROOT_POINTER(struct _machine_i2s_obj_t *machine_i2s_obj[I2S_NUM_AUTO]);
|