Squashed 'lib/lufa/' content from commit 385d40300

git-subtree-dir: lib/lufa
git-subtree-split: 385d4030035dbaf41591309dbde47653bd03841b

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diff --git a/Demos/Device/LowLevel/AudioInput/AudioInput.c b/Demos/Device/LowLevel/AudioInput/AudioInput.c
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+++ b/Demos/Device/LowLevel/AudioInput/AudioInput.c
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+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2017.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2017  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
+  software without specific, written prior permission.
+
+  The author disclaims all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+/** \file
+ *
+ *  Main source file for the Audio Input demo. This file contains the main tasks of the demo and
+ *  is responsible for the initial application hardware configuration.
+ */
+
+#include "AudioInput.h"
+
+/** Flag to indicate if the streaming audio alternative interface has been selected by the host. */
+static bool StreamingAudioInterfaceSelected = false;
+
+/** Current audio sampling frequency of the streaming audio endpoint. */
+static uint32_t CurrentAudioSampleFrequency = 48000;
+
+
+/** Main program entry point. This routine contains the overall program flow, including initial
+ *  setup of all components and the main program loop.
+ */
+int main(void)
+{
+	SetupHardware();
+
+	LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
+	GlobalInterruptEnable();
+
+	for (;;)
+	{
+		USB_USBTask();
+	}
+}
+
+/** Configures the board hardware and chip peripherals for the demo's functionality. */
+void SetupHardware(void)
+{
+#if (ARCH == ARCH_AVR8)
+	/* Disable watchdog if enabled by bootloader/fuses */
+	MCUSR &= ~(1 << WDRF);
+	wdt_disable();
+
+	/* Disable clock division */
+	clock_prescale_set(clock_div_1);
+#endif
+
+	/* Hardware Initialization */
+	LEDs_Init();
+	Buttons_Init();
+	ADC_Init(ADC_FREE_RUNNING | ADC_PRESCALE_32);
+	ADC_SetupChannel(MIC_IN_ADC_CHANNEL);
+	USB_Init();
+
+	/* Start the ADC conversion in free running mode */
+	ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | ADC_GET_CHANNEL_MASK(MIC_IN_ADC_CHANNEL));
+}
+
+/** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs, and
+ *  configures the sample update and PWM timers.
+ */
+void EVENT_USB_Device_Connect(void)
+{
+	/* Indicate USB enumerating */
+	LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
+
+	/* Sample reload timer initialization */
+	TIMSK0  = (1 << OCIE0A);
+	OCR0A   = ((F_CPU / 8 / CurrentAudioSampleFrequency) - 1);
+	TCCR0A  = (1 << WGM01);  // CTC mode
+	TCCR0B  = (1 << CS01);   // Fcpu/8 speed
+}
+
+/** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via
+ *  the status LEDs, disables the sample update and PWM output timers and stops the USB and Audio management tasks.
+ */
+void EVENT_USB_Device_Disconnect(void)
+{
+	/* Stop the sample reload timer */
+	TCCR0B = 0;
+
+	/* Indicate streaming audio interface not selected */
+	StreamingAudioInterfaceSelected = false;
+
+	/* Indicate USB not ready */
+	LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
+}
+
+/** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration
+ *  of the USB device after enumeration - the device endpoints are configured.
+ */
+void EVENT_USB_Device_ConfigurationChanged(void)
+{
+	bool ConfigSuccess = true;
+
+	/* Setup Audio Stream Endpoint */
+	ConfigSuccess &= Endpoint_ConfigureEndpoint(AUDIO_STREAM_EPADDR, EP_TYPE_ISOCHRONOUS, AUDIO_STREAM_EPSIZE, 2);
+
+	/* Indicate endpoint configuration success or failure */
+	LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
+}
+
+/** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to
+ *  the device from the USB host before passing along unhandled control requests to the library for processing
+ *  internally.
+ */
+void EVENT_USB_Device_ControlRequest(void)
+{
+	/* Process General and Audio specific control requests */
+	switch (USB_ControlRequest.bRequest)
+	{
+		case REQ_SetInterface:
+			/* Set Interface is not handled by the library, as its function is application-specific */
+			if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_STANDARD | REQREC_INTERFACE))
+			{
+				Endpoint_ClearSETUP();
+				Endpoint_ClearStatusStage();
+
+				/* Check if the host is enabling the audio interface (setting AlternateSetting to 1) */
+				StreamingAudioInterfaceSelected = ((USB_ControlRequest.wValue) != 0);
+			}
+
+			break;
+		case AUDIO_REQ_GetStatus:
+			/* Get Status request can be directed at either the interface or endpoint, neither is currently used
+			 * according to the latest USB Audio 1.0 standard, but must be ACKed with no data when requested */
+			if ((USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE)) ||
+			    (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_ENDPOINT)))
+			{
+				Endpoint_ClearSETUP();
+				Endpoint_ClearStatusStage();
+			}
+
+			break;
+		case AUDIO_REQ_SetCurrent:
+			if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_ENDPOINT))
+			{
+				/* Extract out the relevant request information to get the target Endpoint address and control being set */
+				uint8_t EndpointAddress = (uint8_t)USB_ControlRequest.wIndex;
+				uint8_t EndpointControl = (USB_ControlRequest.wValue >> 8);
+
+				/* Only handle SET CURRENT requests to the audio endpoint's sample frequency property */
+				if ((EndpointAddress == AUDIO_STREAM_EPADDR) && (EndpointControl == AUDIO_EPCONTROL_SamplingFreq))
+				{
+					uint8_t SampleRate[3];
+
+					Endpoint_ClearSETUP();
+					Endpoint_Read_Control_Stream_LE(SampleRate, sizeof(SampleRate));
+					Endpoint_ClearIN();
+
+					/* Set the new sampling frequency to the value given by the host */
+					CurrentAudioSampleFrequency = (((uint32_t)SampleRate[2] << 16) | ((uint32_t)SampleRate[1] << 8) | (uint32_t)SampleRate[0]);
+
+					/* Adjust sample reload timer to the new frequency */
+					OCR0A = ((F_CPU / 8 / CurrentAudioSampleFrequency) - 1);
+				}
+			}
+
+			break;
+		case AUDIO_REQ_GetCurrent:
+			if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_ENDPOINT))
+			{
+				/* Extract out the relevant request information to get the target Endpoint address and control being retrieved */
+				uint8_t EndpointAddress = (uint8_t)USB_ControlRequest.wIndex;
+				uint8_t EndpointControl = (USB_ControlRequest.wValue >> 8);
+
+				/* Only handle GET CURRENT requests to the audio endpoint's sample frequency property */
+				if ((EndpointAddress == AUDIO_STREAM_EPADDR) && (EndpointControl == AUDIO_EPCONTROL_SamplingFreq))
+				{
+					uint8_t SampleRate[3];
+
+					/* Convert the sampling rate value into the 24-bit format the host expects for the property */
+					SampleRate[2] = (CurrentAudioSampleFrequency >> 16);
+					SampleRate[1] = (CurrentAudioSampleFrequency >> 8);
+					SampleRate[0] = (CurrentAudioSampleFrequency &  0xFF);
+
+					Endpoint_ClearSETUP();
+					Endpoint_Write_Control_Stream_LE(SampleRate, sizeof(SampleRate));
+					Endpoint_ClearOUT();
+				}
+			}
+
+			break;
+	}
+}
+
+/** ISR to handle the reloading of the data endpoint with the next sample. */
+ISR(TIMER0_COMPA_vect, ISR_BLOCK)
+{
+	uint8_t PrevEndpoint = Endpoint_GetCurrentEndpoint();
+
+	/* Select the audio stream endpoint */
+	Endpoint_SelectEndpoint(AUDIO_STREAM_EPADDR);
+
+	/* Check if the current endpoint can be written to and that the audio interface is enabled */
+	if (Endpoint_IsINReady() && StreamingAudioInterfaceSelected)
+	{
+		int16_t AudioSample;
+
+		#if defined(USE_TEST_TONE)
+			static uint8_t SquareWaveSampleCount;
+			static int16_t CurrentWaveValue;
+
+			/* In test tone mode, generate a square wave at 1/256 of the sample rate */
+			if (SquareWaveSampleCount++ == 0xFF)
+			  CurrentWaveValue ^= 0x8000;
+
+			/* Only generate audio if the board button is being pressed */
+			AudioSample = (Buttons_GetStatus() & BUTTONS_BUTTON1) ? CurrentWaveValue : 0;
+		#else
+			/* Audio sample is ADC value scaled to fit the entire range */
+			AudioSample = ((SAMPLE_MAX_RANGE / ADC_MAX_RANGE) * ADC_GetResult());
+
+			#if defined(MICROPHONE_BIASED_TO_HALF_RAIL)
+			/* Microphone is biased to half rail voltage, subtract the bias from the sample value */
+			AudioSample -= (SAMPLE_MAX_RANGE / 2);
+			#endif
+		#endif
+
+		/* Write the sample to the buffer */
+		Endpoint_Write_16_LE(AudioSample);
+
+		/* Check to see if the bank is now full */
+		if (!(Endpoint_IsReadWriteAllowed()))
+		{
+			/* Send the full packet to the host */
+			Endpoint_ClearIN();
+		}
+	}
+
+	Endpoint_SelectEndpoint(PrevEndpoint);
+}
+