#include <avr/io.h>
#include "../../../Common/Common.h"
#include "../LowLevel/HostChapter9.h"
#include "../HighLevel/StdDescriptors.h"
Defines | |
#define | DESCRIPTOR_PCAST(DescriptorPtr, Type) ((Type*)DescriptorPtr) |
#define | DESCRIPTOR_CAST(DescriptorPtr, Type) (*DESCRIPTOR_PCAST(DescriptorPtr, Type)) |
#define | DESCRIPTOR_TYPE(DescriptorPtr) DESCRIPTOR_CAST(DescriptorPtr, USB_Descriptor_Header_t).Type |
#define | DESCRIPTOR_SIZE(DescriptorPtr) DESCRIPTOR_CAST(DescriptorPtr, USB_Descriptor_Header_t).Size |
#define | DESCRIPTOR_COMPARATOR(name) uint8_t DCOMP_##name (void* const CurrentDescriptor) |
#define | USB_Host_GetNextDescriptorComp(DSize, DPos, DSearch) USB_Host_GetNextDescriptorComp_P(DSize, DPos, DCOMP_##DSearch) |
Enumerations | |
enum | DSEARCH_Return_ErrorCodes_t { Descriptor_Search_Found = 0, Descriptor_Search_Fail = 1, Descriptor_Search_NotFound = 2 } |
enum | DSEARCH_Comp_Return_ErrorCodes_t { Descriptor_Search_Comp_Found = 0, Descriptor_Search_Comp_Fail = 1, Descriptor_Search_Comp_EndOfDescriptor = 2 } |
Functions | |
uint8_t | USB_Host_GetDeviceConfigDescriptor (uint16_t *const ConfigSizePtr, void *BufferPtr) ATTR_NON_NULL_PTR_ARG(1) |
static void | USB_Host_GetNextDescriptor (uint16_t *const BytesRem, uint8_t **const CurrConfigLoc) ATTR_NON_NULL_PTR_ARG(1 |
void | USB_Host_GetNextDescriptorOfType (uint16_t *const BytesRem, uint8_t **const CurrConfigLoc, const uint8_t Type) ATTR_NON_NULL_PTR_ARG(1 |
void void | USB_Host_GetNextDescriptorOfTypeBefore (uint16_t *const BytesRem, uint8_t **const CurrConfigLoc, const uint8_t Type, const uint8_t BeforeType) ATTR_NON_NULL_PTR_ARG(1 |
void void void | USB_Host_GetNextDescriptorOfTypeAfter (uint16_t *const BytesRem, uint8_t **const CurrConfigLoc, const uint8_t Type, const uint8_t AfterType) ATTR_NON_NULL_PTR_ARG(1 |
#define DESCRIPTOR_CAST | ( | DescriptorPtr, | |||
Type | ) | (*DESCRIPTOR_PCAST(DescriptorPtr, Type)) |
Casts a pointer to a descriptor inside the configuration descriptor into the given descriptor type (as an actual struct instance rather than a pointer to a struct).
Usage Example:
uint8_t* CurrDescriptor = &ConfigDescriptor[0]; // Pointing to the configuration header USB_Descriptor_Configuration_Header_t ConfigHeader = DESCRIPTOR_CAST(CurrDescriptor, USB_Descriptor_Configuration_Header_t); // Can now access elements of the configuration header struct using the . operator
#define DESCRIPTOR_COMPARATOR | ( | name | ) | uint8_t DCOMP_##name (void* const CurrentDescriptor) |
Creates a prototype for or begins a descriptor comparitor routine. Descriptor comparitor routines are small search routines which are passed a pointer to the current sub descriptor in the configuration descriptor, and which analyse the sub descriptor to determine whether or not it matches the routine's search parameters. Comparitor routines provide a powerful way to scan through the config descriptor for certain descriptors matching unique criteria.
Comparitor routines are passed in a single pointer named CurrentDescriptor, and should return a value of a member of the DSEARCH_Return_ErrorCodes_t enum.
#define DESCRIPTOR_PCAST | ( | DescriptorPtr, | |||
Type | ) | ((Type*)DescriptorPtr) |
Casts a pointer to a descriptor inside the configuration descriptor into a pointer to the given descriptor type.
Usage Example:
uint8_t* CurrDescriptor = &ConfigDescriptor[0]; // Pointing to the configuration header USB_Descriptor_Configuration_Header_t* ConfigHeaderPtr = DESCRIPTOR_PCAST(CurrDescriptor, USB_Descriptor_Configuration_Header_t); // Can now access elements of the configuration header struct using the -> indirection operator
#define DESCRIPTOR_SIZE | ( | DescriptorPtr | ) | DESCRIPTOR_CAST(DescriptorPtr, USB_Descriptor_Header_t).Size |
Returns the descriptor's size, expressed as the 8-bit value indicating the number of bytes.
#define DESCRIPTOR_TYPE | ( | DescriptorPtr | ) | DESCRIPTOR_CAST(DescriptorPtr, USB_Descriptor_Header_t).Type |
Returns the descriptor's type, expressed as the 8-bit type value in the header of the descriptor. This value's meaning depends on the descriptor's placement in the descriptor, but standard type values can be accessed in the DescriptorTypes_t enum located in USB/HighLevel/StdDescriptors.h.
#define USB_Host_GetNextDescriptorComp | ( | DSize, | |||
DPos, | |||||
DSearch | ) | USB_Host_GetNextDescriptorComp_P(DSize, DPos, DCOMP_##DSearch) |
Searches for the next descriptor in the given configuration descriptor using a premade comparator function. The routine updates the position and remaining configuration descriptor bytes values automatically. If a comparator routine fails a search, the descriptor pointer is retreated back so that the next descriptor search invocation will start from the descriptor which first caused the original search to fail. This behaviour allows for one comparator to be used immediately after another has failed, starting the second search from the descriptor which failed the first.
DSize | Pointer to an int storing the remaining bytes in the configuration descriptor | |
DPos | Pointer to the current position in the configuration descriptor | |
DSearch | Name of the comparitor search function to use on the configuration descriptor |
DESCRIPTOR_COMPARATOR(EndpointSearcher); // Comparator Prototype DESCRIPTOR_COMPARATOR(EndpointSearcher) { if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Endpoint) return Descriptor_Search_Found; else return Descriptor_Search_NotFound; } //... // After retrieving configuration descriptor: if (USB_Host_GetNextDescriptorComp(&BytesRemaining, &ConfigDescriptorData, EndpointSearcher) == Descriptor_Search_Comp_Found) { // Do something with the endpoint descriptor }
Enum for return values of USB_Host_GetNextDescriptorComp()
Enum for return values of a descriptor comparator made with DESCRIPTOR_COMPARATOR.
uint8_t USB_Host_GetDeviceConfigDescriptor | ( | uint16_t *const | ConfigSizePtr, | |
void * | BufferPtr | |||
) |
Retrieves the configuration descriptor data or size from an attached device via a standard request.
ConfigSizePtr | Pointer to a uint16_t for either storing or retrieving the configuration descriptor size | |
BufferPtr | Pointer to the buffer for storing the configuration descriptor data. If this is NULL, the size of the configuration descriptor will be retrieved instead and placed in the variable pointed to by ConfigSizePtr. If this is non-NULL, the number of bytes indicated by ConfigSizePtr of the configuration descriptor will be loaded into the buffer |
static void static void USB_Host_GetNextDescriptor | ( | uint16_t *const | BytesRem, | |
uint8_t **const | CurrConfigLoc | |||
) | [inline, static] |
Skips over the current sub-descriptor inside the configuration descriptor, so that the pointer then points to the next sub-descriptor. The bytes remaining value is automatically decremented.
BytesRem | Pointer to the number of bytes remaining of the configuration descriptor | |
CurrConfigLoc | Pointer to the current descriptor inside the configuration descriptor |
void USB_Host_GetNextDescriptorOfType | ( | uint16_t *const | BytesRem, | |
uint8_t **const | CurrConfigLoc, | |||
const uint8_t | Type | |||
) |
Skips to the next sub-descriptor inside the configuration descriptor of the specified type value. The bytes remaining value is automatically decremented.
BytesRem | Pointer to the number of bytes remaining of the configuration descriptor | |
CurrConfigLoc | Pointer to the current descriptor inside the configuration descriptor | |
Type | Descriptor type value to search for |
void void void USB_Host_GetNextDescriptorOfTypeAfter | ( | uint16_t *const | BytesRem, | |
uint8_t **const | CurrConfigLoc, | |||
const uint8_t | Type, | |||
const uint8_t | AfterType | |||
) |
Skips to the next sub-descriptor inside the configuration descriptor of the specified type value, which must come after a descriptor of the second given type value. The bytes remaining value is automatically decremented.
BytesRem | Pointer to the number of bytes remaining of the configuration descriptor | |
CurrConfigLoc | Pointer to the current descriptor inside the configuration descriptor | |
Type | Descriptor type value to search for | |
AfterType | Descriptor type value which must be reached before the given Type descriptor |
void void USB_Host_GetNextDescriptorOfTypeBefore | ( | uint16_t *const | BytesRem, | |
uint8_t **const | CurrConfigLoc, | |||
const uint8_t | Type, | |||
const uint8_t | BeforeType | |||
) |
Skips to the next sub-descriptor inside the configuration descriptor of the specified type value, which must come before a descriptor of the second given type value. If the BeforeType type descriptor is reached first, the number of bytes remaining to process is set to zero and the function exits. The bytes remaining value is automatically decremented.
BytesRem | Pointer to the number of bytes remaining of the configuration descriptor | |
CurrConfigLoc | Pointer to the current descriptor inside the configuration descriptor | |
Type | Descriptor type value to search for | |
BeforeType | Descriptor type value which must not be reached before the given Type descriptor |