usbstdreq.c File Reference

#include "type.h"
#include "usbdebug.h"
#include "usbstruct.h"
#include "usbapi.h"

Include dependency graph for usbstdreq.c:

Defines
#define	MAX_DESC_HANDLERS   4
#define	DESC_bLength   0
#define	DESC_bDescriptorType   1
#define	CONF_DESC_wTotalLength   2
#define	CONF_DESC_bConfigurationValue   5
#define	INTF_DESC_bAlternateSetting   3
#define	ENDP_DESC_bEndpointAddress   2
#define	ENDP_DESC_wMaxPacketSize   4
Functions
void	USBRegisterDescriptors (const U8 *pabDescriptors)
BOOL	USBGetDescriptor (U16 wTypeIndex, U16 wLangID, int *piLen, U8 **ppbData)
BOOL	USBHandleStandardRequest (TSetupPacket *pSetup, int *piLen, U8 **ppbData)
void	USBRegisterCustomReqHandler (TFnHandleRequest *pfnHandler)

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Detailed Description

Standard request handler.

This modules handles the 'chapter 9' processing, specifically the standard device requests in table 9-3 from the universal serial bus specification revision 2.0

Specific types of devices may specify additional requests (for example HID devices add a GET_DESCRIPTOR request for interfaces), but they will not be part of this module.

Todo:

some requests have to return a request error if device not configured:

GET_INTERFACE, GET_STATUS, SET_INTERFACE, SYNCH_FRAME

this applies to the following if endpoint != 0:

SET_FEATURE, GET_FEATURE

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Define Documentation

#define CONF_DESC_bConfigurationValue   5

configuration value offset

#define CONF_DESC_wTotalLength   2

total length offset

#define DESC_bDescriptorType   1

descriptor type offset

#define DESC_bLength   0

length offset

#define ENDP_DESC_bEndpointAddress   2

endpoint address offset

#define ENDP_DESC_wMaxPacketSize   4

maximum packet size offset

#define INTF_DESC_bAlternateSetting   3

alternate setting offset

#define MAX_DESC_HANDLERS   4

device, interface, endpoint, other

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Function Documentation

BOOL USBGetDescriptor (  U16  wTypeIndex, U16  wLangID, int *  piLen, U8 **  ppbData )

Parses the list of installed USB descriptors and attempts to find the specified USB descriptor. Parameters: [in]  wTypeIndex  Type and index of the descriptor [in]  wLangID  Language ID of the descriptor (currently unused) [out]  *piLen  Descriptor length [out]  *ppbData  Descriptor data Returns: TRUE if the descriptor was found, FALSE otherwise

BOOL USBHandleStandardRequest (  TSetupPacket *  pSetup, int *  piLen, U8 **  ppbData )

Default handler for standard ('chapter 9') requests If a custom request handler was installed, this handler is called first. Parameters: [in]  pSetup  The setup packet [in,out]  *piLen  Pointer to data length [in]  ppbData  Data buffer. Returns: TRUE if the request was handled successfully

void USBRegisterCustomReqHandler (  TFnHandleRequest *  pfnHandler  )

Registers a callback for custom device requests In USBHandleStandardRequest, the custom request handler gets a first chance at handling the request before it is handed over to the 'chapter 9' request handler. This can be used for example in HID devices, where a REQ_GET_DESCRIPTOR request is sent to an interface, which is not covered by the 'chapter 9' specification. Parameters: [in]  pfnHandler  Callback function pointer

void USBRegisterDescriptors (  const U8 *  pabDescriptors  )

Registers a pointer to a descriptor block containing all descriptors for the device. Parameters: [in]  pabDescriptors  The descriptor byte array

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