diff options
Diffstat (limited to 'Demos/Host/Incomplete/AndroidAccessoryHost/ConfigDescriptor.c')
-rw-r--r-- | Demos/Host/Incomplete/AndroidAccessoryHost/ConfigDescriptor.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/Demos/Host/Incomplete/AndroidAccessoryHost/ConfigDescriptor.c b/Demos/Host/Incomplete/AndroidAccessoryHost/ConfigDescriptor.c new file mode 100644 index 000000000..6fce72b3a --- /dev/null +++ b/Demos/Host/Incomplete/AndroidAccessoryHost/ConfigDescriptor.c @@ -0,0 +1,138 @@ +/*
+ LUFA Library
+ Copyright (C) Dean Camera, 2011.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.lufa-lib.org
+*/
+
+/*
+ Copyright 2011 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 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 the first interface containing bulk IN and OUT data endpoints.
+ *
+ * \return An error code from the \ref AndroidHost_GetConfigDescriptorDataCodes_t enum.
+ */
+uint8_t ProcessConfigurationDescriptor(void)
+{
+ uint8_t ConfigDescriptorData[512];
+ void* CurrConfigLocation = ConfigDescriptorData;
+ uint16_t CurrConfigBytesRem;
+
+ USB_Descriptor_Endpoint_t* DataINEndpoint = 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 DevControlError;
+ }
+
+ /* The Android Accessory Mode specification mandates that the accessory communications endpoints
+ be in the first interface descriptor (interface 0) */
+ USB_GetNextDescriptorOfType(&CurrConfigBytesRem, &CurrConfigLocation, DTYPE_Interface);
+
+ /* Ensure that an interface was found, and the end of the descriptor was not reached */
+ if (!(CurrConfigBytesRem))
+ return NoCompatibleInterfaceFound;
+
+ while (!(DataINEndpoint) || !(DataOUTEndpoint))
+ {
+ /* Get the next Still Image interface's data endpoint descriptor */
+ if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
+ DCOMP_NextInterfaceBulkEndpoint) != DESCRIPTOR_SEARCH_COMP_Found)
+ {
+ /* Data endpoints not found within the first Android Accessory device interface, error out */
+ return NoCompatibleInterfaceFound;
+ }
+
+ /* Retrieve the endpoint address from the endpoint descriptor */
+ USB_Descriptor_Endpoint_t* EndpointData = DESCRIPTOR_PCAST(CurrConfigLocation, USB_Descriptor_Endpoint_t);
+
+ /* If the endpoint is a IN type endpoint */
+ if (EndpointData->EndpointAddress & ENDPOINT_DESCRIPTOR_DIR_IN)
+ DataINEndpoint = EndpointData;
+ else
+ DataOUTEndpoint = EndpointData;
+ }
+
+ /* Configure the Android Accessory data IN pipe */
+ Pipe_ConfigurePipe(ANDROID_DATA_IN_PIPE, EP_TYPE_BULK, PIPE_TOKEN_IN,
+ DataINEndpoint->EndpointAddress, DataINEndpoint->EndpointSize, PIPE_BANK_SINGLE);
+
+ /* Configure the Android Accessory data OUT pipe */
+ Pipe_ConfigurePipe(ANDROID_DATA_OUT_PIPE, EP_TYPE_BULK, PIPE_TOKEN_OUT,
+ DataOUTEndpoint->EndpointAddress, DataOUTEndpoint->EndpointSize, PIPE_BANK_SINGLE);
+
+ /* 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 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
+ */
+uint8_t DCOMP_NextInterfaceBulkEndpoint(void* const 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);
+
+ uint8_t EndpointType = (Endpoint->Attributes & EP_TYPE_MASK);
+ if ((EndpointType == EP_TYPE_BULK) && (!(Pipe_IsEndpointBound(Endpoint->EndpointAddress))))
+ return DESCRIPTOR_SEARCH_Found;
+ }
+ else if (Header->Type == DTYPE_Interface)
+ {
+ return DESCRIPTOR_SEARCH_Fail;
+ }
+
+ return DESCRIPTOR_SEARCH_NotFound;
+}
+
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