--- /dev/null
+/*
+ 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
+ *
+ * USB Device Configuration Descriptor processing routines, to determine the correct pipe configurations
+ * needed to communication with an attached USB device. Descriptors are special computer-readable structures
+ * which the host requests upon device enumeration, to determine the device's capabilities and functions.
+ */
+
+#include "ConfigDescriptor.h"
+
+/** Index of the currently used Audio Streaming Interface within the device. */
+uint8_t StreamingInterfaceIndex = 0;
+
+/** Alternative Setting of the currently used Audio Streaming Interface within the device. */
+uint8_t StreamingInterfaceAltSetting = 0;
+
+/** Address of the streaming audio endpoint currently in use within the device. */
+uint8_t StreamingEndpointAddress = 0;
+
+
+/** Reads and processes an attached device's descriptors, to determine compatibility and pipe configurations. This
+ * routine will read in the entire configuration descriptor, and configure the hosts pipes to correctly communicate
+ * with compatible devices.
+ *
+ * This routine searches for a Streaming Audio interface descriptor containing a valid Isochronous audio endpoint.
+ *
+ * \return An error code from the \ref AudioHost_GetConfigDescriptorDataCodes_t enum.
+ */
+uint8_t ProcessConfigurationDescriptor(void)
+{
+ uint8_t ConfigDescriptorData[512];
+ void* CurrConfigLocation = ConfigDescriptorData;
+ uint16_t CurrConfigBytesRem;
+
+ USB_Descriptor_Interface_t* AudioControlInterface = NULL;
+ USB_Descriptor_Interface_t* AudioStreamingInterface = NULL;
+ USB_Descriptor_Endpoint_t* DataOUTEndpoint = NULL;
+
+ /* Retrieve the entire configuration descriptor into the allocated buffer */
+ switch (USB_Host_GetDeviceConfigDescriptor(1, &CurrConfigBytesRem, ConfigDescriptorData, sizeof(ConfigDescriptorData)))
+ {
+ case HOST_GETCONFIG_Successful:
+ break;
+ case HOST_GETCONFIG_InvalidData:
+ return InvalidConfigDataReturned;
+ case HOST_GETCONFIG_BuffOverflow:
+ return DescriptorTooLarge;
+ default:
+ return ControlError;
+ }
+
+ while (!(DataOUTEndpoint))
+ {
+ /* See if we've found a likely compatible interface, and if there is an endpoint within that interface */
+ if (!(AudioControlInterface) ||
+ USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
+ DComp_NextAudioInterfaceDataEndpoint) != DESCRIPTOR_SEARCH_COMP_Found)
+ {
+ /* Check if we haven't found an Audio Control interface yet, or if we have run out of related Audio Streaming interfaces */
+ if (!(AudioControlInterface) ||
+ USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
+ DComp_NextAudioStreamInterface) != DESCRIPTOR_SEARCH_COMP_Found)
+ {
+ /* Find a new Audio Control interface if the current one doesn't contain a compatible streaming interface */
+ if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
+ DComp_NextAudioControlInterface) != DESCRIPTOR_SEARCH_COMP_Found)
+ {
+ /* Descriptor not found, error out */
+ return NoCompatibleInterfaceFound;
+ }
+
+ /* Save the interface in case we need to refer back to it later */
+ AudioControlInterface = DESCRIPTOR_PCAST(CurrConfigLocation, USB_Descriptor_Interface_t);
+
+ /* Find the next Audio Streaming interface within that Audio Control interface */
+ if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
+ DComp_NextAudioStreamInterface) != DESCRIPTOR_SEARCH_COMP_Found)
+ {
+ /* Descriptor not found, error out */
+ return NoCompatibleInterfaceFound;
+ }
+ }
+
+ /* Save the interface in case we need to refer back to it later */
+ AudioStreamingInterface = DESCRIPTOR_PCAST(CurrConfigLocation, USB_Descriptor_Interface_t);
+
+ /* Skip the remainder of the loop as we have not found an endpoint yet */
+ continue;
+ }
+
+ /* Retrieve the endpoint address from the endpoint descriptor */
+ USB_Descriptor_Endpoint_t* EndpointData = DESCRIPTOR_PCAST(CurrConfigLocation, USB_Descriptor_Endpoint_t);
+
+ /* Save the endpoint if it is an OUT type endpoint */
+ if ((EndpointData->EndpointAddress & ENDPOINT_DIR_MASK) == ENDPOINT_DIR_OUT)
+ DataOUTEndpoint = EndpointData;
+ }
+
+ StreamingInterfaceIndex = AudioStreamingInterface->InterfaceNumber;
+ StreamingInterfaceAltSetting = AudioStreamingInterface->AlternateSetting;
+ StreamingEndpointAddress = DataOUTEndpoint->EndpointAddress;
+
+ /* Configure the Audio data OUT pipe */
+ Pipe_ConfigurePipe(AUDIO_DATA_OUT_PIPE, EP_TYPE_ISOCHRONOUS, DataOUTEndpoint->EndpointAddress, DataOUTEndpoint->EndpointSize, 2);
+
+ /* Valid data found, return success */
+ return SuccessfulConfigRead;
+}
+
+/** Descriptor comparator function. This comparator function is can be called while processing an attached USB device's
+ * configuration descriptor, to search for a specific sub descriptor. It can also be used to abort the configuration
+ * descriptor processing if an incompatible descriptor configuration is found.
+ *
+ * This comparator searches for the next Interface descriptor of the correct Audio Control Class, Subclass and Protocol values.
+ *
+ * \return A value from the DSEARCH_Return_ErrorCodes_t enum
+ */
+uint8_t DComp_NextAudioControlInterface(void* CurrentDescriptor)
+{
+ USB_Descriptor_Header_t* Header = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Header_t);
+
+ if (Header->Type == DTYPE_Interface)
+ {
+ USB_Descriptor_Interface_t* Interface = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Interface_t);
+
+ if ((Interface->Class == AUDIO_CSCP_AudioClass) &&
+ (Interface->SubClass == AUDIO_CSCP_ControlSubclass) &&
+ (Interface->Protocol == AUDIO_CSCP_ControlProtocol))
+ {
+ return DESCRIPTOR_SEARCH_Found;
+ }
+ }
+
+ return DESCRIPTOR_SEARCH_NotFound;
+}
+
+/** Descriptor comparator function. This comparator function is can be called while processing an attached USB device's
+ * configuration descriptor, to search for a specific sub descriptor. It can also be used to abort the configuration
+ * descriptor processing if an incompatible descriptor configuration is found.
+ *
+ * This comparator searches for the next Interface descriptor of the correct Audio Streaming Class, Subclass and Protocol values.
+ *
+ * \return A value from the DSEARCH_Return_ErrorCodes_t enum
+ */
+uint8_t DComp_NextAudioStreamInterface(void* CurrentDescriptor)
+{
+ USB_Descriptor_Header_t* Header = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Header_t);
+
+ if (Header->Type == DTYPE_Interface)
+ {
+ USB_Descriptor_Interface_t* Interface = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Interface_t);
+
+ if ((Interface->Class == AUDIO_CSCP_AudioClass) &&
+ (Interface->SubClass == AUDIO_CSCP_AudioStreamingSubclass) &&
+ (Interface->Protocol == AUDIO_CSCP_StreamingProtocol))
+ {
+ return DESCRIPTOR_SEARCH_Found;
+ }
+ }
+
+ return DESCRIPTOR_SEARCH_NotFound;
+}
+
+/** Descriptor comparator function. This comparator function is can be called while processing an attached USB device's
+ * configuration descriptor, to search for a specific sub descriptor. It can also be used to abort the configuration
+ * descriptor processing if an incompatible descriptor configuration is found.
+ *
+ * This comparator searches for the next Isochronous Endpoint descriptor within the current interface, aborting the
+ * search if another interface descriptor is found before the next endpoint.
+ *
+ * \return A value from the DSEARCH_Return_ErrorCodes_t enum
+ */
+uint8_t DComp_NextAudioInterfaceDataEndpoint(void* CurrentDescriptor)
+{
+ USB_Descriptor_Header_t* Header = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Header_t);
+
+ if (Header->Type == DTYPE_Endpoint)
+ {
+ USB_Descriptor_Endpoint_t* Endpoint = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Endpoint_t);
+
+ if ((Endpoint->Attributes & EP_TYPE_MASK) == EP_TYPE_ISOCHRONOUS)
+ return DESCRIPTOR_SEARCH_Found;
+ }
+ else if (Header->Type == DTYPE_Interface)
+ {
+ return DESCRIPTOR_SEARCH_Fail;
+ }
+
+ return DESCRIPTOR_SEARCH_NotFound;
+}
+
projects / qmk_firmware.git / blobdiff