diff options
Diffstat (limited to 'Demos/StillImageHost/ConfigDescriptor.c')
| -rw-r--r-- | Demos/StillImageHost/ConfigDescriptor.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/Demos/StillImageHost/ConfigDescriptor.c b/Demos/StillImageHost/ConfigDescriptor.c new file mode 100644 index 000000000..a336c1f5e --- /dev/null +++ b/Demos/StillImageHost/ConfigDescriptor.c @@ -0,0 +1,191 @@ +/*
+ 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 SI interface descriptor containing bulk IN and OUT data endpoints.
+ *
+ * \return An error code from the StillImageHost_GetConfigDescriptorDataCodes_t enum.
+ */
+uint8_t ProcessConfigurationDescriptor(void)
+{
+ uint8_t* ConfigDescriptorData;
+ uint16_t ConfigDescriptorSize;
+ uint8_t FoundEndpoints = 0;
+
+ /* 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 Still Image interface from the configuration descriptor */
+ if (USB_Host_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData, NextStillImageInterface))
+ {
+ /* Descriptor not found, error out */
+ return NoInterfaceFound;
+ }
+
+ /* Get the IN and OUT data and event endpoints for the Still Image interface */
+ while (FoundEndpoints != ((1 << SIMAGE_EVENTS_PIPE) | (1 << SIMAGE_DATA_IN_PIPE) | (1 << SIMAGE_DATA_OUT_PIPE)))
+ {
+ /* Fetch the next endpoint from the current Still Image interface */
+ if (USB_Host_GetNextDescriptorComp(&ConfigDescriptorSize, &ConfigDescriptorData,
+ NextSImageInterfaceDataEndpoint))
+ {
+ /* Descriptor not found, error out */
+ return NoEndpointFound;
+ }
+
+ USB_Descriptor_Endpoint_t* EndpointData = DESCRIPTOR_PCAST(ConfigDescriptorData, USB_Descriptor_Endpoint_t);
+
+ /* Check if the found endpoint is a interrupt or bulk type descriptor */
+ if ((EndpointData->Attributes & EP_TYPE_MASK) == EP_TYPE_INTERRUPT)
+ {
+ /* If the endpoint is a IN type interrupt endpoint */
+ if (EndpointData->EndpointAddress & ENDPOINT_DESCRIPTOR_DIR_IN)
+ {
+ /* Configure the events pipe */
+ Pipe_ConfigurePipe(SIMAGE_EVENTS_PIPE, EP_TYPE_INTERRUPT, PIPE_TOKEN_IN,
+ EndpointData->EndpointAddress, EndpointData->EndpointSize,
+ PIPE_BANK_DOUBLE);
+
+ Pipe_SetInfiniteINRequests();
+ Pipe_SetInterruptPeriod(EndpointData->PollingIntervalMS);
+
+ /* Set the flag indicating that the events pipe has been found */
+ FoundEndpoints |= (1 << SIMAGE_EVENTS_PIPE);
+ }
+ }
+ else
+ {
+ /* Check if the endpoint is a bulk IN or bulk OUT endpoint */
+ if (EndpointData->EndpointAddress & ENDPOINT_DESCRIPTOR_DIR_IN)
+ {
+ /* Configure the data IN pipe */
+ Pipe_ConfigurePipe(SIMAGE_DATA_IN_PIPE, EP_TYPE_BULK, PIPE_TOKEN_IN,
+ EndpointData->EndpointAddress, EndpointData->EndpointSize,
+ PIPE_BANK_DOUBLE);
+
+ Pipe_SetInfiniteINRequests();
+
+ /* Set the flag indicating that the data IN pipe has been found */
+ FoundEndpoints |= (1 << SIMAGE_DATA_IN_PIPE);
+ }
+ else
+ {
+ /* Configure the data OUT pipe */
+ Pipe_ConfigurePipe(SIMAGE_DATA_OUT_PIPE, EP_TYPE_BULK, PIPE_TOKEN_OUT,
+ EndpointData->EndpointAddress, EndpointData->EndpointSize,
+ PIPE_BANK_DOUBLE);
+
+ /* Set the flag indicating that the data OUT pipe has been found */
+ FoundEndpoints |= (1 << SIMAGE_DATA_OUT_PIPE);
+ }
+ }
+ }
+
+ /* 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 Still Image Class, Subclass and Protocol values.
+ *
+ * \return A value from the DSEARCH_Return_ErrorCodes_t enum
+ */
+DESCRIPTOR_COMPARATOR(NextStillImageInterface)
+{
+ if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface)
+ {
+ /* Check the descriptor class and protocol, break out if correct class/protocol interface found */
+ if ((DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Class == SIMAGE_CLASS) &&
+ (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).SubClass == SIMAGE_SUBCLASS) &&
+ (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Protocol == SIMAGE_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 Interrupt or Bulk Endpoint descriptor of the current SI interface, aborting the
+ * search if another interface descriptor is found before the next endpoint.
+ *
+ * \return A value from the DSEARCH_Return_ErrorCodes_t enum
+ */
+DESCRIPTOR_COMPARATOR(NextSImageInterfaceDataEndpoint)
+{
+ if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Endpoint)
+ {
+ uint8_t EndpointType = (DESCRIPTOR_CAST(CurrentDescriptor,
+ USB_Descriptor_Endpoint_t).Attributes & EP_TYPE_MASK);
+
+ if ((EndpointType == EP_TYPE_BULK) || (EndpointType == EP_TYPE_INTERRUPT))
+ return Descriptor_Search_Found;
+ }
+ else if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface)
+ {
+ return Descriptor_Search_Fail;
+ }
+
+ return Descriptor_Search_NotFound;
+}
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