/* LUFA Library Copyright (C) Dean Camera, 2009. dean [at] fourwalledcubicle [dot] com www.fourwalledcubicle.com */ /* Copyright 2009 Dean Camera (dean [at] fourwalledcubicle [dot] com) Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, 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 disclaim 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" /** 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 HID interface descriptor containing at least one Interrupt type IN endpoint and HID descriptor. * * \return An error code from the MouseHostWithParser_GetConfigDescriptorDataCodes_t enum. */ uint8_t ProcessConfigurationDescriptor(void) { uint8_t* ConfigDescriptorData; uint16_t ConfigDescriptorSize; uint8_t ErrorCode; /* Get Configuration Descriptor size from the device */ if (USB_Host_GetDeviceConfigDescriptor(&ConfigDescriptorSize, NULL) != HOST_SENDCONTROL_Successful) return ControlError; /* Ensure that the Configuration Descriptor isn't too large */ if (ConfigDescriptorSize > MAX_CONFIG_DESCRIPTOR_SIZE) return DescriptorTooLarge; /* Allocate enough memory for the entire config descriptor */ ConfigDescriptorData = alloca(ConfigDescriptorSize); /* Retrieve the entire configuration descriptor into the allocated buffer */ USB_Host_GetDeviceConfigDescriptor(&ConfigDescriptorSize, ConfigDescriptorData); /* Validate returned data - ensure first entry is a configuration header descriptor */ if (DESCRIPTOR_TYPE(ConfigDescriptorData) != DTYPE_Configuration) return InvalidConfigDataReturned; /* Get the mouse interface from the configuration descriptor */ if ((ErrorCode = USB_Host_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, NextMouseInterface))) { /* Descriptor not found, error out */ return NoHIDInterfaceFound; } /* Get the mouse interface's HID descriptor */ if ((ErrorCode = USB_Host_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, NextHID))) { /* Descriptor not found, error out */ return NoHIDDescriptorFound; } /* Save the HID report size for later use */ HIDReportSize = DESCRIPTOR_CAST(ConfigDescriptorData, USB_Descriptor_HID_t).HIDReportLength; /* Get the mouse interface's data endpoint descriptor */ if ((ErrorCode = USB_Host_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, NextInterfaceMouseDataEndpoint))) { /* Descriptor not found, error out */ return NoEndpointFound; } /* Retrieve the endpoint address from the endpoint descriptor */ USB_Descriptor_Endpoint_t* EndpointData = DESCRIPTOR_PCAST(ConfigDescriptorData, USB_Descriptor_Endpoint_t); /* Configure the mouse data pipe */ Pipe_ConfigurePipe(MOUSE_DATAPIPE, EP_TYPE_INTERRUPT, PIPE_TOKEN_IN, EndpointData->EndpointAddress, EndpointData->EndpointSize, PIPE_BANK_SINGLE); Pipe_SetInfiniteINRequests(); /* 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 Mouse HID Class and Protocol values. * * \return A value from the DSEARCH_Return_ErrorCodes_t enum */ DESCRIPTOR_COMPARATOR(NextMouseInterface) { if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface) { /* Check the HID descriptor class and protocol, break out if correct class/protocol interface found */ if ((DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Class == MOUSE_CLASS) && (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Protocol == MOUSE_PROTOCOL)) { 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 IN Endpoint descriptor inside the current interface descriptor, * aborting the search if another interface descriptor is found before the required endpoint. * * \return A value from the DSEARCH_Return_ErrorCodes_t enum */ DESCRIPTOR_COMPARATOR(NextInterfaceMouseDataEndpoint) { if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Endpoint) { if (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Endpoint_t).EndpointAddress & ENDPOINT_DESCRIPTOR_DIR_IN) return Descriptor_Search_Found; } else if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface) { return Descriptor_Search_Fail; } 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 HID descriptor within the current HID interface descriptor. * * \return A value from the DSEARCH_Return_ErrorCodes_t enum */ DESCRIPTOR_COMPARATOR(NextHID) { if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_HID) return Descriptor_Search_Found; else return Descriptor_Search_NotFound; }