Implement audiobusio and enhance PIO for it

This adds I2SOut and PDMIn support via PIO.

StateMachines can now:
 * read and read while writing
 * transfer in 1, 2 or 4 byte increments
 * init pins based on expected defaults automatically
 * be stopped and restarted
 * rxfifo can be cleared and rxstalls detected (good for tracking when
   the reading code isn't keeping up)

Fixes #4162

Author: tannewt

ports/raspberrypi/audio_dma.c

@@ -39,6 +39,16 @@
 
 #define AUDIO_DMA_CHANNEL_COUNT NUM_DMA_CHANNELS
 
+void audio_dma_reset(void) {
+    for (size_t channel = 0; channel < AUDIO_DMA_CHANNEL_COUNT; channel++) {
+        if (MP_STATE_PORT(playing_audio)[channel] == NULL) {
+            continue;
+        }
+
+        audio_dma_stop(MP_STATE_PORT(playing_audio)[channel]);
+    }
+}
+
 void audio_dma_convert_signed(audio_dma_t* dma, uint8_t* buffer, uint32_t buffer_length,
                               uint8_t** output_buffer, uint32_t* output_buffer_length) {
     if (dma->first_buffer_free) {
@@ -292,9 +302,16 @@ void audio_dma_stop(audio_dma_t* dma) {
     for (size_t i = 0; i < 2; i++) {
         size_t channel = dma->channel[i];
 
+        dma_channel_config c = dma_channel_get_default_config(dma->channel[i]);
+        channel_config_set_enable(&c, false);
+        dma_channel_set_config(channel, &c, false /* trigger */);
+
         if (dma_channel_is_busy(channel)) {
             dma_channel_abort(channel);
         }
+        dma_channel_set_read_addr(channel, NULL, false /* trigger */);
+        dma_channel_set_write_addr(channel, NULL, false /* trigger */);
+        dma_channel_set_trans_count(channel, 0, false /* trigger */);
         dma_channel_unclaim(channel);
         MP_STATE_PORT(playing_audio)[channel] = NULL;
         dma->channel[i] = NUM_DMA_CHANNELS;

ports/raspberrypi/bindings/rp2pio/StateMachine.c

@@ -36,36 +36,38 @@
 extern const mp_obj_type_t rp2pio_statemachine_type;
 
 // Construct an underlying SPI object.
-extern void common_hal_rp2pio_statemachine_construct(rp2pio_statemachine_obj_t *self,
+void common_hal_rp2pio_statemachine_construct(rp2pio_statemachine_obj_t *self,
     const uint16_t* program, size_t program_len,
     size_t frequency,
     const uint16_t* init, size_t init_len,
-    const mcu_pin_obj_t * first_out_pin, uint8_t out_pin_count,
+    const mcu_pin_obj_t * first_out_pin, uint8_t out_pin_count, uint32_t initial_out_pin_state, uint32_t initial_out_pin_direction,
     const mcu_pin_obj_t * first_in_pin, uint8_t in_pin_count,
-    const mcu_pin_obj_t * first_set_pin, uint8_t set_pin_count,
-    const mcu_pin_obj_t * first_sideset_pin, uint8_t sideset_pin_count,
+    const mcu_pin_obj_t * first_set_pin, uint8_t set_pin_count, uint32_t initial_set_pin_state, uint32_t initial_set_pin_direction,
+    const mcu_pin_obj_t * first_sideset_pin, uint8_t sideset_pin_count, uint32_t initial_sideset_pin_state, uint32_t initial_sideset_pin_direction,
     bool exclusive_pin_use,
     bool auto_pull, uint8_t pull_threshold, bool out_shift_right,
+    bool wait_for_txstall,
     bool auto_push, uint8_t push_threshold, bool in_shift_right);
 
-extern void common_hal_rp2pio_statemachine_deinit(rp2pio_statemachine_obj_t *self);
-extern bool common_hal_rp2pio_statemachine_deinited(rp2pio_statemachine_obj_t *self);
+void common_hal_rp2pio_statemachine_deinit(rp2pio_statemachine_obj_t *self);
+bool common_hal_rp2pio_statemachine_deinited(rp2pio_statemachine_obj_t *self);
 
-// Writes out the given data.
-extern bool common_hal_rp2pio_statemachine_write(rp2pio_statemachine_obj_t *self, const uint8_t *data, size_t len);
-
-// // Reads in len bytes while outputting zeroes.
-// extern bool common_hal_rp2pio_statemachine_read(rp2pio_statemachine_obj_t *self, uint8_t *data, size_t len, uint8_t write_value);
+void common_hal_rp2pio_statemachine_restart(rp2pio_statemachine_obj_t *self);
+void common_hal_rp2pio_statemachine_stop(rp2pio_statemachine_obj_t *self);
+void common_hal_rp2pio_statemachine_run(rp2pio_statemachine_obj_t *self, const uint16_t *instructions, size_t len);
 
-// // Reads and write len bytes simultaneously.
-// extern bool common_hal_rp2pio_statemachine_transfer(rp2pio_statemachine_obj_t *self,
-//                                           const uint8_t *data_out, size_t out_len,
-//                                           uint8_t *data_in, size_t in_len);
+// Writes out the given data.
+bool common_hal_rp2pio_statemachine_write(rp2pio_statemachine_obj_t *self, const uint8_t *data, size_t len, uint8_t stride_in_bytes);
+bool common_hal_rp2pio_statemachine_readinto(rp2pio_statemachine_obj_t *self, uint8_t *data, size_t len, uint8_t stride_in_bytes);
+bool common_hal_rp2pio_statemachine_write_readinto(rp2pio_statemachine_obj_t *self,
+                                                   const uint8_t *data_out, size_t out_len, uint8_t out_stride_in_bytes,
+                                                   uint8_t *data_in, size_t in_len, uint8_t in_stride_in_bytes);
 
-// Return actual SPI bus frequency.
+// Return actual state machine frequency.
 uint32_t common_hal_rp2pio_statemachine_get_frequency(rp2pio_statemachine_obj_t* self);
+void common_hal_rp2pio_statemachine_set_frequency(rp2pio_statemachine_obj_t* self, uint32_t frequency);
 
-// This is used by the supervisor to claim SPI devices indefinitely.
-// extern void common_hal_rp2pio_statemachine_never_reset(rp2pio_statemachine_obj_t *self);
+bool common_hal_rp2pio_statemachine_get_rxstall(rp2pio_statemachine_obj_t* self);
+void common_hal_rp2pio_statemachine_clear_rxfifo(rp2pio_statemachine_obj_t *self);
 
 #endif // MICROPY_INCLUDED_RASPBERRYPI_BINDINGS_RP2PIO_STATEMACHINE_H

ports/raspberrypi/bindings/rp2pio/StateMachine.h

@@ -0,0 +1,224 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2021 Scott Shawcroft 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 <stdint.h>
+#include <string.h>
+
+#include "mpconfigport.h"
+
+#include "py/gc.h"
+#include "py/mperrno.h"
+#include "py/runtime.h"
+#include "common-hal/audiobusio/I2SOut.h"
+#include "shared-bindings/audiobusio/I2SOut.h"
+#include "shared-bindings/microcontroller/Pin.h"
+#include "shared-module/audiocore/__init__.h"
+#include "bindings/rp2pio/StateMachine.h"
+#include "supervisor/shared/translate.h"
+
+const uint16_t i2s_program[] = {
+// ; Load the next set of samples
+//                     ;        /--- LRCLK
+//                     ;        |/-- BCLK
+//                     ;        ||
+//     pull noblock      side 0b01 ; Loads OSR with the next FIFO value or X
+    0x8880,
+//     mov x osr         side 0b01 ; Save the new value in case we need it again
+    0xa827,
+//     set y 14          side 0b01
+    0xe84e,
+// bitloop1:
+//     out pins 1        side 0b00 [2]
+    0x6201,
+//     jmp y-- bitloop1  side 0b01 [2]
+    0x0a83,
+//     out pins 1        side 0b10 [2]
+    0x7201,
+//     set y 14          side 0b11 [2]
+    0xfa4e,
+// bitloop0:
+//     out pins 1        side 0b10 [2]
+    0x7201,
+//     jmp y-- bitloop0  side 0b11 [2]
+    0x1a87,
+//     out pins 1        side 0b00 [2]
+    0x6201
+};
+
+const uint16_t i2s_program_left_justified[] = {
+// ; Load the next set of samples
+//                     ;        /--- LRCLK
+//                     ;        |/-- BCLK
+//                     ;        ||
+//     pull noblock      side 0b11 ; Loads OSR with the next FIFO value or X
+    0x9880,
+//     mov x osr         side 0b11 ; Save the new value in case we need it again
+    0xb827,
+//     set y 14          side 0b11
+    0xf84e,
+// bitloop1:
+//     out pins 1        side 0b00 [2]
+    0x6201,
+//     jmp y-- bitloop1  side 0b01 [2]
+    0x0a83,
+//     out pins 1        side 0b10 [2]
+    0x6201,
+//     set y 14          side 0b01 [2]
+    0xea4e,
+// bitloop0:
+//     out pins 1        side 0b10 [2]
+    0x7201,
+//     jmp y-- bitloop0  side 0b11 [2]
+    0x1a87,
+//     out pins 1        side 0b10 [2]
+    0x7201
+};
+
+void i2sout_reset(void) {
+}
+
+// Caller validates that pins are free.
+void common_hal_audiobusio_i2sout_construct(audiobusio_i2sout_obj_t* self,
+        const mcu_pin_obj_t* bit_clock, const mcu_pin_obj_t* word_select,
+        const mcu_pin_obj_t* data, bool left_justified) {
+    if (bit_clock->number != word_select->number - 1) {
+        mp_raise_ValueError(translate("Bit clock and word select must be sequential pins"));
+    }
+
+    const uint16_t* program = i2s_program;
+    size_t program_len = sizeof(i2s_program) / sizeof(i2s_program[0]);
+    if (left_justified) {
+        program = i2s_program_left_justified;
+        program_len = sizeof(i2s_program_left_justified) / sizeof(i2s_program_left_justified[0]);;
+    }
+
+    // Use the state machine to manage pins.
+    common_hal_rp2pio_statemachine_construct(&self->state_machine,
+        program, program_len,
+        44100 * 32 * 6, // Clock at 44.1 khz to warm the DAC up.
+        NULL, 0,
+        data, 1, 0, 0xffffffff, // out pin
+        NULL, 0, // in pins
+        NULL, 0, 0, 0x1f, // set pins
+        bit_clock, 2, 0, 0x1f, // sideset pins
+        true, // exclusive pin use
+        false, 32, false, // shift out left to start with MSB
+        false, // Wait for txstall
+        false, 32, false); // in settings
+
+    self->playing = false;
+    audio_dma_init(&self->dma);
+}
+
+bool common_hal_audiobusio_i2sout_deinited(audiobusio_i2sout_obj_t* self) {
+    return common_hal_rp2pio_statemachine_deinited(&self->state_machine);
+}
+
+void common_hal_audiobusio_i2sout_deinit(audiobusio_i2sout_obj_t* self) {
+    if (common_hal_audiobusio_i2sout_deinited(self)) {
+        return;
+    }
+
+    common_hal_rp2pio_statemachine_deinit(&self->state_machine);
+}
+
+void common_hal_audiobusio_i2sout_play(audiobusio_i2sout_obj_t* self,
+                                       mp_obj_t sample, bool loop) {
+    if (common_hal_audiobusio_i2sout_get_playing(self)) {
+        common_hal_audiobusio_i2sout_stop(self);
+    }
+    uint8_t bits_per_sample = audiosample_bits_per_sample(sample);
+    // Make sure we transmit a minimum of 16 bits.
+    // TODO: Maybe we need an intermediate object to upsample instead. This is
+    // only needed for some I2S devices that expect at least 8.
+    if (bits_per_sample < 16) {
+        bits_per_sample = 16;
+    }
+    // We always output stereo so output twice as many bits.
+    uint16_t bits_per_sample_output = bits_per_sample * 2;
+    size_t clocks_per_bit = 6;
+    uint32_t frequency = bits_per_sample_output * audiosample_sample_rate(sample);
+    common_hal_rp2pio_statemachine_set_frequency(&self->state_machine, clocks_per_bit * frequency);
+    common_hal_rp2pio_statemachine_restart(&self->state_machine);
+
+    uint8_t channel_count = audiosample_channel_count(sample);
+    if (channel_count > 2) {
+        mp_raise_ValueError(translate("Too many channels in sample."));
+    }
+
+    audio_dma_result result = audio_dma_setup_playback(
+        &self->dma,
+        sample,
+        loop,
+        false, // single channel
+        0, // audio channel
+        true,  // output signed
+        bits_per_sample,
+        (uint32_t) &self->state_machine.pio->txf[self->state_machine.state_machine], // output register
+        self->state_machine.tx_dreq); // data request line
+
+    if (result == AUDIO_DMA_DMA_BUSY) {
+        common_hal_audiobusio_i2sout_stop(self);
+        mp_raise_RuntimeError(translate("No DMA channel found"));
+    } else if (result == AUDIO_DMA_MEMORY_ERROR) {
+        common_hal_audiobusio_i2sout_stop(self);
+        mp_raise_RuntimeError(translate("Unable to allocate buffers for signed conversion"));
+    }
+
+    // Turn on the state machine's clock.
+
+    self->playing = true;
+}
+
+void common_hal_audiobusio_i2sout_pause(audiobusio_i2sout_obj_t* self) {
+    audio_dma_pause(&self->dma);
+}
+
+void common_hal_audiobusio_i2sout_resume(audiobusio_i2sout_obj_t* self) {
+    // Maybe: Clear any overrun/underrun errors
+
+    audio_dma_resume(&self->dma);
+}
+
+bool common_hal_audiobusio_i2sout_get_paused(audiobusio_i2sout_obj_t* self) {
+    return audio_dma_get_paused(&self->dma);
+}
+
+void common_hal_audiobusio_i2sout_stop(audiobusio_i2sout_obj_t* self) {
+    audio_dma_stop(&self->dma);
+
+    common_hal_rp2pio_statemachine_stop(&self->state_machine);
+
+    self->playing = false;
+}
+
+bool common_hal_audiobusio_i2sout_get_playing(audiobusio_i2sout_obj_t* self) {
+    bool playing = audio_dma_get_playing(&self->dma);
+    if (!playing && self->playing) {
+        common_hal_audiobusio_i2sout_stop(self);
+    }
+    return playing;
+}

ports/raspberrypi/common-hal/audiobusio/I2SOut.c

@@ -0,0 +1,47 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2021 Scott Shawcroft 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_RASPBERRYPI_COMMON_HAL_AUDIOBUSIO_I2SOUT_H
+#define MICROPY_INCLUDED_RASPBERRYPI_COMMON_HAL_AUDIOBUSIO_I2SOUT_H
+
+#include "common-hal/microcontroller/Pin.h"
+#include "common-hal/rp2pio/StateMachine.h"
+
+#include "audio_dma.h"
+#include "py/obj.h"
+
+// We don't bit pack because we'll only have two at most. Its better to save code size instead.
+typedef struct {
+    mp_obj_base_t base;
+    bool left_justified;
+    rp2pio_statemachine_obj_t state_machine;
+    bool playing;
+    audio_dma_t dma;
+} audiobusio_i2sout_obj_t;
+
+void i2sout_reset(void);
+
+#endif // MICROPY_INCLUDED_RASPBERRYPI_COMMON_HAL_AUDIOBUSIO_I2SOUT_H