Begin work on quad channel audio input

Audio.h

 #include "filter_variable.h"
 #include "input_adc.h"
 #include "input_i2s.h"
+#include "input_i2s_quad.h"
 #include "mixer.h"
 #include "output_dac.h"
 #include "output_i2s.h"

input_i2s_quad.cpp

+/* Audio Library for Teensy 3.X
+ * Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com
+ *
+ * Development of this audio library was funded by PJRC.COM, LLC by sales of
+ * Teensy and Audio Adaptor boards.  Please support PJRC's efforts to develop
+ * open source software by purchasing Teensy or other PJRC products.
+ *
+ * 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, development funding 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 "input_i2s_quad.h"
+#include "output_i2s_quad.h"
+
+DMAMEM static uint32_t i2s_rx_buffer[AUDIO_BLOCK_SAMPLES*2];
+audio_block_t * AudioInputI2SQuad::block_ch1 = NULL;
+audio_block_t * AudioInputI2SQuad::block_ch2 = NULL;
+audio_block_t * AudioInputI2SQuad::block_ch3 = NULL;
+audio_block_t * AudioInputI2SQuad::block_ch4 = NULL;
+uint16_t AudioInputI2SQuad::block_offset = 0;
+bool AudioInputI2SQuad::update_responsibility = false;
+DMAChannel AudioInputI2SQuad::dma(false);
+
+#if defined(__MK20DX256__)
+
+void AudioInputI2SQuad::begin(void)
+{
+	dma.begin(true); // Allocate the DMA channel first
+
+	// TODO: should we set & clear the I2S_RCSR_SR bit here?
+	AudioOutputI2SQuad::config_i2s();
+
+	CORE_PIN13_CONFIG = PORT_PCR_MUX(4); // pin 13, PTC5, I2S0_RXD0
+	CORE_PIN30_CONFIG = PORT_PCR_MUX(4); // pin 30, PTC11, I2S0_RXD1
+
+#if defined(KINETISK)
+	dma.TCD->SADDR = &I2S0_RDR0;
+	dma.TCD->SOFF = 4;
+	dma.TCD->ATTR = DMA_TCD_ATTR_SSIZE(1) | DMA_TCD_ATTR_SMOD(3) | DMA_TCD_ATTR_DSIZE(1);
+	dma.TCD->NBYTES_MLNO = 4;
+	dma.TCD->SLAST = 0;
+	dma.TCD->DADDR = i2s_rx_buffer;
+	dma.TCD->DOFF = 2;
+	dma.TCD->CITER_ELINKNO = sizeof(i2s_rx_buffer) / 4;
+	dma.TCD->DLASTSGA = -sizeof(i2s_rx_buffer);
+	dma.TCD->BITER_ELINKNO = sizeof(i2s_rx_buffer) / 4;
+	dma.TCD->CSR = DMA_TCD_CSR_INTHALF | DMA_TCD_CSR_INTMAJOR;
+#endif
+	dma.triggerAtHardwareEvent(DMAMUX_SOURCE_I2S0_RX);
+	update_responsibility = update_setup();
+	dma.enable();
+
+	I2S0_RCSR |= I2S_RCSR_RE | I2S_RCSR_BCE | I2S_RCSR_FRDE | I2S_RCSR_FR;
+	I2S0_TCSR |= I2S_TCSR_TE | I2S_TCSR_BCE; // TX clock enable, because sync'd to TX
+	dma.attachInterrupt(isr);
+}
+
+void AudioInputI2SQuad::isr(void)
+{
+	uint32_t daddr, offset;
+	const int16_t *src;
+	int16_t *dest1, *dest2, *dest3, *dest4;
+
+	//digitalWriteFast(3, HIGH);
+	daddr = (uint32_t)(dma.TCD->DADDR);
+	dma.clearInterrupt();
+
+	if (daddr < (uint32_t)i2s_rx_buffer + sizeof(i2s_rx_buffer) / 2) {
+		// DMA is receiving to the first half of the buffer
+		// need to remove data from the second half
+		src = (int16_t *)&i2s_rx_buffer[AUDIO_BLOCK_SAMPLES];
+		if (update_responsibility) update_all();
+	} else {
+		// DMA is receiving to the second half of the buffer
+		// need to remove data from the first half
+		src = (int16_t *)&i2s_rx_buffer[0];
+	}
+	if (block_ch1) {
+		offset = block_offset;
+		if (offset <= AUDIO_BLOCK_SAMPLES/2) {
+			block_offset = offset + AUDIO_BLOCK_SAMPLES/2;
+			dest1 = &(block_ch1->data[offset]);
+			dest2 = &(block_ch2->data[offset]);
+			dest3 = &(block_ch3->data[offset]);
+			dest4 = &(block_ch4->data[offset]);
+			for (int i=0; i < AUDIO_BLOCK_SAMPLES/2; i++) {
+				*dest1++ = *src++;
+				*dest3++ = *src++;
+				*dest2++ = *src++;
+				*dest4++ = *src++;
+			}
+		}
+	}
+	//digitalWriteFast(3, LOW);
+}
+
+
+void AudioInputI2SQuad::update(void)
+{
+	audio_block_t *new1, *new2, *new3, *new4;
+	audio_block_t *out1, *out2, *out3, *out4;
+
+	// allocate 4 new blocks
+	new1 = allocate();
+	new2 = allocate();
+	new3 = allocate();
+	new4 = allocate();
+	// but if any fails, allocate none
+	if (!new1 || !new2 || !new3 || !new4) {
+		if (new1) {
+			release(new1);
+			new1 = NULL;
+		}
+		if (new2) {
+			release(new2);
+			new2 = NULL;
+		}
+		if (new3) {
+			release(new3);
+			new3 = NULL;
+		}
+		if (new4) {
+			release(new4);
+			new4 = NULL;
+		}
+	}
+	__disable_irq();
+	if (block_offset >= AUDIO_BLOCK_SAMPLES) {
+		// the DMA filled 4 blocks, so grab them and get the
+		// 4 new blocks to the DMA, as quickly as possible
+		out1 = block_ch1;
+		block_ch1 = new1;
+		out2 = block_ch2;
+		block_ch2 = new2;
+		out3 = block_ch3;
+		block_ch3 = new3;
+		out4 = block_ch4;
+		block_ch4 = new4;
+		block_offset = 0;
+		__enable_irq();
+		// then transmit the DMA's former blocks
+		transmit(out1, 0);
+		release(out1);
+		transmit(out2, 1);
+		release(out2);
+		transmit(out3, 2);
+		release(out3);
+		transmit(out4, 3);
+		release(out4);
+	} else if (new1 != NULL) {
+		// the DMA didn't fill blocks, but we allocated blocks
+		if (block_ch1 == NULL) {
+			// the DMA doesn't have any blocks to fill, so
+			// give it the ones we just allocated
+			block_ch1 = new1;
+			block_ch2 = new2;
+			block_ch3 = new3;
+			block_ch4 = new4;
+			block_offset = 0;
+			__enable_irq();
+		} else {
+			// the DMA already has blocks, doesn't need these
+			__enable_irq();
+			release(new1);
+			release(new2);
+			release(new3);
+			release(new4);
+		}
+	} else {
+		// The DMA didn't fill blocks, and we could not allocate
+		// memory... the system is likely starving for memory!
+		// Sadly, there's nothing we can do.
+		__enable_irq();
+	}
+}
+
+#else // not __MK20DX256__
+
+void AudioInputI2SQuad::begin(void)
+{
+}
+
+
+
+#endif
+

input_i2s_quad.h

+/* Audio Library for Teensy 3.X
+ * Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com
+ *
+ * Development of this audio library was funded by PJRC.COM, LLC by sales of
+ * Teensy and Audio Adaptor boards.  Please support PJRC's efforts to develop
+ * open source software by purchasing Teensy or other PJRC products.
+ *
+ * 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, development funding 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 _input_i2s_quad_h_
+#define _input_i2s_quad_h_
+
+#include "AudioStream.h"
+#include "DMAChannel.h"
+
+class AudioInputI2SQuad : public AudioStream
+{
+public:
+	AudioInputI2SQuad(void) : AudioStream(0, NULL) { begin(); }
+	virtual void update(void);
+	void begin(void);
+private:
+	static bool update_responsibility;
+	static DMAChannel dma;
+	static void isr(void);
+	static audio_block_t *block_ch1;
+	static audio_block_t *block_ch2;
+	static audio_block_t *block_ch3;
+	static audio_block_t *block_ch4;
+	static uint16_t block_offset;
+};
+
+
+#endif

keywords.txt

 Audio	KEYWORD2
 AudioConnection	KEYWORD2
 AudioInputI2S	KEYWORD2
+AudioInputI2SQuad	KEYWORD2
 AudioInputI2Sslave	KEYWORD2
 AudioOutputI2S	KEYWORD2
 AudioOutputI2SQuad	KEYWORD2

output_i2s_quad.h

 	AudioOutputI2SQuad(void) : AudioStream(4, inputQueueArray) { begin(); }
 	virtual void update(void);
 	void begin(void);
+	friend class AudioInputI2SQuad;
 private:
 	static void config_i2s(void);
 	static audio_block_t *block_ch1_1st;