/* Copyright (C) 2011 Circuits At Home, LTD. All rights reserved.
This software may be distributed and modified under the terms of the GNU
General Public License version 2 (GPL2) as published by the Free Software
Foundation and appearing in the file GPL2.TXT included in the packaging of
this file. Please note that GPL2 Section 2[b] requires that all works based
on this software must also be made publicly available under the terms of
the GPL2 ("Copyleft").
Contact information
-------------------
Circuits At Home, LTD
Web : http://www.circuitsathome.com
e-mail : support@circuitsathome.com
*/
#ifndef CONFDESCPARSER_H_INCLUDED
#define CONFDESCPARSER_H_INCLUDED
#include <stdint.h>
#include "parsetools.h"
/**
* \class Abstract UsbConfigXtracter definition.
*
* \note This class is used for extracting USB endpoint descriptors.
*/
class UsbConfigXtracter
{
public:
virtual void EndpointXtract(uint32_t conf, uint32_t iface, uint32_t alt, uint32_t proto, const USB_ENDPOINT_DESCRIPTOR *ep) = 0;
};
#define CP_MASK_COMPARE_CLASS 1
#define CP_MASK_COMPARE_SUBCLASS 2
#define CP_MASK_COMPARE_PROTOCOL 4
#define CP_MASK_COMPARE_ALL 7
/**
* \class ConfigDescParser definition.
*
* \note This class is used for parsing configuration descriptors.
*/
template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
class ConfigDescParser : public USBReadParser
{
UsbConfigXtracter *theXtractor;
MultiValueBuffer theBuffer;
MultiByteValueParser valParser;
ByteSkipper theSkipper;
uint8_t varBuffer[16 /*sizeof(USB_CONFIGURATION_DESCRIPTOR)*/];
uint32_t stateParseDescr; // ParseDescriptor state
uint32_t dscrLen; // Descriptor length
uint32_t dscrType; // Descriptor type
bool isGoodInterface; // Apropriate interface flag
uint32_t confValue; // Configuration value
uint32_t protoValue; // Protocol value
uint32_t ifaceNumber; // Interface number
uint32_t ifaceAltSet; // Interface alternate settings
bool ParseDescriptor(uint8_t **pp, uint32_t *pcntdn);
void PrintHidDescriptor(const USB_HID_DESCRIPTOR *pDesc);
public:
ConfigDescParser(UsbConfigXtracter *xtractor);
virtual void Parse(const uint32_t len, const uint8_t *pbuf, const uint32_t &offset);
};
/**
* \brief ConfigDescParser class constructor.
*
* \param xtractor Is saved as ConfigDescParser attribute and later used as a
* callback for parsing the endpoint descriptors.
*
* \note During enumeration stage, all supported USB classes invoke
* ConfigDescParser with "this" as parameter, meaning that one class is also
* responsible for parsing its endpoint descriptors. This makes sense since
* each USB class handles different number of endpoints and configurations.
* For instance see ADK::Init from ADK class.
*/
template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::ConfigDescParser(UsbConfigXtracter *xtractor) :
theXtractor(xtractor),
stateParseDescr(0),
dscrLen(0),
dscrType(0)
{
theBuffer.pValue = varBuffer;
valParser.Initialize(&theBuffer);
theSkipper.Initialize(&theBuffer);
};
/**
* \brief Parse a complete USB configuration descriptor.
*
* \param len Buffer length.
* \param pbuf Buffer containing the configuration descriptor.
* \param offset Current offset position.
*/
template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
void ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::Parse(const uint32_t len, const uint8_t *pbuf, const uint32_t &offset)
{
uint32_t cntdn = len;
uint8_t *p = (uint8_t*)pbuf;
while (cntdn)
if (!ParseDescriptor(&p, &cntdn))
return;
}
/**
* \brief Parse a USB configuration descriptor.
* Takes values for class, subclass, protocol fields in interface descriptor
* and compare masks for them. When the match is found, calls EndpointXtract
* passing buffer containing endpoint descriptor.
*
* \note This method should not be called directly, use Parse() instead.
*
* \param pcntdn Buffer length.
* \param pp Buffer containing the configuration descriptor.
*
* \return true if data remains in the buffer for parsing, false otherwise.
*/
template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
bool ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::ParseDescriptor(uint8_t **pp, uint32_t *pcntdn)
{
switch (stateParseDescr)
{
case 0:
theBuffer.valueSize = 2;
valParser.Initialize(&theBuffer);
stateParseDescr = 1;
case 1:
if (!valParser.Parse(pp, pcntdn))
return false;
dscrLen = *((uint8_t*)theBuffer.pValue);
dscrType = *((uint8_t*)theBuffer.pValue + 1);
stateParseDescr = 2;
case 2:
// This is a sort of hack. Assuming that two bytes are already in the buffer
// the pointer is positioned two bytes ahead in order for the rest of descriptor
// to be read right after the size and the type fields.
// This should be used carefuly. varBuffer should be used directly to handle data
// in the buffer.
theBuffer.pValue = varBuffer + 2;
stateParseDescr = 3;
case 3:
switch (dscrType)
{
case USB_DESCRIPTOR_INTERFACE:
isGoodInterface = false;
case USB_DESCRIPTOR_CONFIGURATION:
theBuffer.valueSize = sizeof(USB_CONFIGURATION_DESCRIPTOR) - 2;
break;
case USB_DESCRIPTOR_ENDPOINT:
theBuffer.valueSize = sizeof(USB_ENDPOINT_DESCRIPTOR) - 2;
break;
case HID_DESCRIPTOR_HID:
theBuffer.valueSize = dscrLen - 2;
break;
}
valParser.Initialize(&theBuffer);
stateParseDescr = 4;
case 4:
switch (dscrType)
{
case USB_DESCRIPTOR_CONFIGURATION:
if (!valParser.Parse(pp, pcntdn))
return false;
confValue = ((USB_CONFIGURATION_DESCRIPTOR*)varBuffer)->bConfigurationValue;
break;
case USB_DESCRIPTOR_INTERFACE:
if (!valParser.Parse(pp, pcntdn))
return false;
if ((MASK & CP_MASK_COMPARE_CLASS) && ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceClass != CLASS_ID)
break;
if ((MASK & CP_MASK_COMPARE_SUBCLASS) && ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceSubClass != SUBCLASS_ID)
break;
if ((MASK & CP_MASK_COMPARE_PROTOCOL) && ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceProtocol != PROTOCOL_ID)
break;
isGoodInterface = true;
ifaceNumber = ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceNumber;
ifaceAltSet = ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bAlternateSetting;
protoValue = ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceProtocol;
break;
case USB_DESCRIPTOR_ENDPOINT:
if (!valParser.Parse(pp, pcntdn))
return false;
if (isGoodInterface)
if (theXtractor)
theXtractor->EndpointXtract(confValue, ifaceNumber, ifaceAltSet, protoValue, (USB_ENDPOINT_DESCRIPTOR*)varBuffer);
break;
//case HID_DESCRIPTOR_HID:
// if (!valParser.Parse(pp, pcntdn))
// return false;
// PrintHidDescriptor((const USB_HID_DESCRIPTOR*)varBuffer);
// break;
default:
if (!theSkipper.Skip(pp, pcntdn, dscrLen - 2))
return false;
}
theBuffer.pValue = varBuffer;
stateParseDescr = 0;
}
return true;
}
/**
* \brief Print HID descriptor.
*
* \note TRACE_USBHOST macro must be enabled. See Usb.h for reference.
*
* \param pDesc Pointer to HID descriptor.
*/
template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
void ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::PrintHidDescriptor(const USB_HID_DESCRIPTOR *pDesc)
{
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : bDescLength: %d\r\n", pDesc->bLength);)
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : bDescriptorType: %d\r\n", pDesc->bDescriptorType);)
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : bcdHID: %d\r\n", pDesc->bcdHID);)
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : bCountryCode: %d\r\n", pDesc->bCountryCode);)
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : bNumDescriptors: %d\r\n", pDesc->bNumDescriptors);)
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : bDescrType: %d\r\n", pDesc->bDescrType);)
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : wDescriptorLength: %d\r\n", pDesc->wDescriptorLength);)
for (uint32_t i = 0; i < pDesc->bNumDescriptors; ++i)
{
HID_CLASS_DESCRIPTOR_LEN_AND_TYPE *pLT = (HID_CLASS_DESCRIPTOR_LEN_AND_TYPE*)&(pDesc->bDescrType);
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : bDescrType: %d\r\n", pLT[i].bDescrType);)
TRACE_USBHOST(printf("ConfigDescParser::PrintHidDescriptor : wDescriptorLength: %d\r\n", pLT[i].wDescriptorLength);)
}
}
#endif /* CONFDESCPARSER_H_INCLUDED */