;USB activity hook

 include "settings.inc"
 include "ti83plus.inc"
 include "equates.inc" 
 SEGMENT Main
 GLOBALS ON
 
 EXTERN DispHexA,DispHexHL,GetControlPacket,WaitPort82,SetupOutPipe,SetupInPipe,SendInterruptData
 EXTERN debugStep,col1,col2,SmallWaitTimer,WaitTimerBms,SendBulkData,handleCalcData,RecycleUSB
 EXTERN DoDebug,ReceiveData,InitializePeriphUSB,receiveAndWriteUSBData,DoLog2

;USB Activity Hook
;--------------------------------------------------------------------------------------------------
USBactivityHook:
	add a,e
;       res debugOn,(iy+periph8xFlags)                   ;***TESTING
;       ld a,(debugStep)                                 ;***TESTING
;       inc a                                            ;
;       ld (debugStep),a                                 ;
;       ld hl,(curRow)                                   ;
;       push hl                                          ;
;       ld hl,0707h                                      ;
;       ld (curRow),hl                                   ;
;       call DispHexA                                    ;
;       pop hl                                           ;
;       ld (curRow),hl                                   ;
       in a,(55h)
;       bit debugOn,(iy+periph8xFlags)                  ;*** TESTING
;       call nz,DispHexA                                ;
       ld b,a
       in a,(56h)
;       bit debugOn,(iy+periph8xFlags)                  ;*** TESTING
;       call nz,DispHexA                                ;
       LOG Interrupt,b
       LOG Interrupt,a
       or a
       jr z,skipPort56h
       ;Port 56h has the event
       bit 6,a
       jr nz,BcablePluggedIn
       bit 4,a
       jr nz,cancelUSBHook ;exitUSBHook ;A cable plugged in
       bit 5,a
       jr nz,cancelUSBHook ;exitUSBHook ;A cable unplugged
       bit 7,a
       jr z,notBcableUnplugged ;cancelUSBHook ;exitUSBHook ;B cable unplugged
       ;kill USB device as peripheral
       call RecycleUSB
       jr cancelUSBHook
       xor a
       out (5Bh),a
       in a,(4Dh)
       bit 5,a
       jr nz,$F
       xor a
       out (4Ch),a
       res 6,(iy+41h)
       jr continueKill
$$:    ld b,8
       in a,(4Dh)
       bit 6,a
       jr nz,$F
       ld b,0
$$:    ld a,b
       out (4Ch),a
continueKill:
       ld a,2
       out (54h),a
       ld a,(39h)
       and 0F8h
       out (39h),a
       res 0,(iy+41h)
       in a,(4Dh)
       bit 5,a
       jr nz,continueKill2
       ld de,0FFFFh
$$:    dec de
       ld a,d
       or e
       scf
       jr z,cancelUSBHook
       in a,(4Dh)
       bit 7,a
       jr z,$B
       in a,(4Dh)
       bit 0,a
       jr z,$B
       ld a,22h
       out (57h),a
       jr cancelUSBHook
continueKill2:
       in a,(4Dh)
       bit 6,a
       jr nz,$F
       xor a
       out (4Ch),a
       ld a,50h
       jr finalKill
$$:    ld a,93h
finalKill:
       out (57h),a
       jr cancelUSBHook
notBcableUnplugged:
       bit 1,a
       jr z,skipPort56h
       ;1,(56h) was set
       call InitializePeriphUSB
       jr nc,cancelUSBHook
       LOG Custom,04h
       jr cancelUSBHook
bit0Port56hSet:
;I have absolutely no idea what 0,(56h) being set means, and we will never know.
;I go ahead and re-initialize just because, though. Who knows, it might actually do the right thing.
       LOG Bit0Port56,a
       call InitializePeriphUSB
       jr cancelUSBHook
skipPort56h:
       in a,(56h)
       bit 0,a
       jr nz,bit0Port56hSet
       in a,(55h)
       ld b,a
       and 11h
       xor 11h
       jr z,cancelUSBHook
       bit 4,b
       jr z,readData
       di
       bit 3,(iy+41h)
       jr nz,cancelUSBHook
       in a,(8Fh)
       bit 7,a
       jr nz,killUSBInterruptDisableError
$$:    xor a
       out (5Bh),a
       ld a,20h
       out (57h),a
       jr killUSBError
bit0Port86hSet:
       in a,(8Fh)
       bit 7,a
       jr z,$B
killUSBInterruptDisableError:
       xor a
       out (5Bh),a
killUSBError:
       call unknownOutputs
       in a,(4Dh)
       bit 5,a
       jr nz,$F
       ld de,0FFFFh
smallLoop:
       dec de
       ld a,d
       or e
       jr z,scfeiUSBError
       in a,(4Dh)
       bit 7,a
       jr z,smallLoop
       in a,(4Dh)
       bit 0,a
       jr z,smallLoop
       ld a,22h
       out (57h),a
       jr cancelUSBHook
$$:    in a,(4Dh)
       bit 6,a
       jr nz,$F
       xor a
       out (4Ch),a
       ld a,50h
       jr outPort57h
$$:    ld a,93h
outPort57h:
       out (57h),a
       jr cancelUSBHook
unknownOutputs:
       in a,(4Dh)
       bit 5,a
       jr nz,$F
       xor a
       res 6,(iy+41h)
       jr port54h39hOutput
$$:    ld b,8
       in a,(4Dh)
       bit 6,a
       jr nz,$F
       ld b,0
$$:    ld a,b
       out (4Ch),a
port54h39hOutput:
       ld a,2
       out (54h),a
       in a,(39h)
       and 0F8h
       out (39h),a
       ret
scfeiUSBError:
       scf
       ei
       ld a,1
       out (5Bh),a
       res 0,(iy+41h)
       jr cancelUSBHook
;Not sure whether this should run or not
       ld b,50
       call WaitTimerBms
       LOG Custom,3                                     ;*** TESTING
       ei
       ld a,1
       out (5Bh),a
       res 0,(iy+41h)
       jr cancelUSBHook
BcablePluggedIn:
       LOG PeriphInit,0
       call InitializePeriphUSB
       jr cancelUSBHook
readData:
       di
       bit 0,(iy+41h)
       jr nz,cancelUSBHook
       in a,(8Fh)
       LOG IntPort8F,a                                 ;*** TESTING
       in a,(86h)
       ld b,a
       LOG IntPort86,a                                 ;*** TESTING
       bit 2,a
       jr nz,enableControlOutput
	in a,(82h)
       LOG IntPort82,a                                 ;*** TESTING
	bit 0,a
	jr nz,controlDataReady
       in a,(84h)
       LOG IntPort84,a
       bit 2,a
       jr nz,bulkDataReady
       bit 0,b
       jr nz,bit0Port86hSet
       LOG Custom,2                                     ;*** TESTING
       jr cancelUSBHook                                 ;*** INCOMPLETE - some sort of data
enableControlOutput:
       LOG EnableOut,0
       xor a
       ld (9C86h),a
       ld a,1
       out (5Bh),a
       in a,(87h)
       or 1
       out (87h),a
       jr cancelUSBHook
controlDataReady:
	xor a
	out (8Eh),a
	in a,(91h)
       LOG ControlData,a
	cp 5							;*** HACK: I have no idea why this is suddenly necessary...
	jr z,receiveControlPacket				;
	ld b,a
	and 4
	jr z,$F
	ld a,b
	and 0FBh
	out (91h),a
	jr cancelUSBHook
$$:	ld a,b
	and 10h
	jr z,$F
	ld a,b
	or 80h
	out (91h),a
$$:	ld a,b
	and 1
	jr nz,receiveControlPacket
       ld hl,USBflag
       bit setAddress,(hl)
	jr z,cancelUSBHook                               ;this should never happen (but apparently it does, OS ignores it)
	res setAddress,(hl)
	ld a,(USBaddress)
       LOG SetAddress,a
	out (80h),a
	jr cancelUSBHook
receiveControlPacket:
	ld hl,inputBuffer
	ld b,8
	call GetControlPacket
;       bit debugOn,(iy+periph8xFlags)                      ;***TESTING
;       call nz,DoDebug                                     ;***TESTING
	ld a,(inputBuffer)
       LOG ControlData,a
	cp 80h
	jr z,deviceToHostReceived
       cp 81h
       jr z,deviceToHostReceived
       cp 02h
       jr z,endpointPacketReceived
	or a
	jr z,hostToDeviceReceived
       ld hl,USBflag
       bit msdActive,(hl)
       jr z,$F
       cp 0A1h
       jr z,getMaxLUNReceived
$$:    bit kbdActive,(hl)
       jr z,stallControlPipeEndHook
       cp 21h
       jr z,classSpecificRequestReceived
       cp 22h
       jr z,classSpecificRequestReceived
stallControlPipeEndHook:
       ld hl,inputBuffer
       ld de,statVars+100h
       ld bc,8
       ldir
       LOG IStallPipe,0
       xor a
       out (8Eh),a
       ld a,60h
       out (91h),a
cancelUSBHook:
	ld b,0
	ret
exitUSBHook:
	ld b,2Ch
	ret
;--------------------------------------------------------------------------------------------------

;Control Requests
;--------------------------------------------------------------------------------------------------
endpointPacketReceived:
       ld a,(inputBuffer+1)
       cp 1
       jr z,clearFeatureEndpoint
       cp 3
       jr z,setFeatureEndpoint
       jr stallControlPipeEndHook
deviceToHostReceived:
	ld a,(inputBuffer+1)
	cp 06h
	jr z,getDescriptorReceived
	jr stallControlPipeEndHook
hostToDeviceReceived:
	ld a,(inputBuffer+1)
	cp 05h
	jr z,setAddressReceived
       cp 09h
       jr z,setConfigurationReceived
       cp 03h
       jr z,setFeatureReceived
       dec a
       jr nz,stallControlPipeEndHook
;Clear feature received
       jr finishControlRequest
setFeatureReceived:
       jr finishControlRequest
classSpecificRequestReceived:
       ld a,(inputBuffer+1)
       cp 0Ah
       jr z,setIdleRequest
       cp 09h
       jr z,setReportRequest
       jr stallControlPipeEndHook

getMaxLUNReceived:
;       LOG OutA0Start,0
       xor a
       out (8Eh),a
       ld a,40h
       out (91h),a
       xor a
       out (0A0h),a
finishControlOutput:
;       bit debugOn,(iy+periph8xFlags)                   ;***TESTING
;       call nz,DoDebug                                  ;***TESTING
       xor a
	out (8Eh),a
	ld a,0Ah
	out (91h),a
	call WaitPort82
;       bit debugOn,(iy+periph8xFlags)                   ;***TESTING
;       call nz,DoDebug                                  ;***TESTING
	call WaitPort82
;       bit debugOn,(iy+periph8xFlags)                   ;***TESTING
;       call nz,DoDebug                                  ;***TESTING
       jr cancelUSBHook
clearFeatureEndpoint:
       ;Something is telling the calculator to clear the halt condition on an endpoint.
       ld a,(inputBuffer+4)
       and 7Fh
       ld (USBaddress),a
       ld a,(inputBuffer+4)
       and 80h
       ld (USBaddress+1),a
       in a,(8Eh)
       push af
       ld a,(USBaddress)
       out (8Eh),a
       ld a,(USBaddress+1)
       or a
       jr z,$F
       in a,(91h)
       and 0EFh
       or 40h
       out (91h),a
       jr endpointReceivedDone
$$:    in a,(94h)
       and 0DFh
       or 80h
       out (94h),a
endpointReceivedDone:
       pop af
       out (8Eh),a
       jr finishControlRequest
setFeatureEndpoint:
       ;Something is telling the calculator to halt an endpoint.
       ld a,(inputBuffer+4)
       and 7Fh
       ld (USBaddress),a
       ld a,(inputBuffer+4)
       and 80h
       ld (USBaddress+1),a
       in a,(8Eh)
       push af
       ld a,(USBaddress)
       out (8Eh),a
       ld a,(USBaddress+1)
       or a
       jr nz,$F
       ld a,10h
       out (91h),a
       jr endpointReceivedDone
$$:    ld a,20h
       out (91h),a
       jr endpointReceivedDone
setReportRequest:
       xor a
       out (8Eh),a
       ld a,40h
       out (91h),a
       ld de,0FFFFh
$$:    dec de
       ld a,d
       or e
       jr z,stallControlPipeEndHook
       in a,(82h)
       and 1
       jr z,$B
       in a,(91h)
       and 1
       jr z,stallControlPipeEndHook
       in a,(96h)
       dec a
       jr nz,stallControlPipeEndHook
       in a,(0A0h)                                      ;this is probably 01, don't really care either way
       jr finishControlRequest
setConfigurationReceived:
       LOG SetConfig,0
       ld a,1
       out (8Eh),a
       ld a,1
       ld hl,USBflag
       set driverConfigured,(hl)                        ;HID/other communication can start now
       bit kbdActive,(hl)
       jr nz,$F
       ld a,8
$$:    call SetupOutPipe
       ld a,2
       out (8Eh),a
       bit kbdActive,(hl)
       jr nz,$F
       ld a,8
       call SetupInPipe
       jr finishSetConfiguration
$$:    ld a,1
       out (8Eh),a
       ld a,0Ah
       out (99h),a
       ld a,31h
       out (98h),a
       xor a
       in a,(98h)
       ld a,c
       out (90h),a
       xor a
       in a,(90h)
finishSetConfiguration:
       xor a
       ld (bytesRemaining),a
       jr finishControlRequest
setAddressReceived:
	ld a,(inputBuffer+2)
       LOG GotSetAddr,a
	ld (USBaddress),a
       ld hl,USBflag
       set setAddress,(hl)
	ld a,1
	out (5Bh),a
	ld a,7Fh
	out (87h),a
       ld a,0Eh
       out (89h),a
       jr finishControlRequest
getDescriptorReceived:
;       xor a                                            ;***TESTING
;       ld (col1),a                                      ;***TESTING
       ld a,(inputBuffer+3)
;       call DispHexA
       LOG ReadDescriptor,a
	dec a ;cp 01h
	jr z,deviceDescriptorReceived
       dec a ;cp 02h
	jr z,configDescriptorReceived
       dec a ;cp 03h
       jr z,stringDescriptorReceived
       cp 22h-3
       jr z,reportDescriptorReceived
	jr stallControlPipeEndHook
reportDescriptorReceived:
       ;set debugOn,(iy+periph8xFlags)                   ;***TESTING
       ld a,(inputBuffer+4)
       or a
;       ld de,HIDreportDescriptor
       jr nz,stallControlPipeEndHook
       ld a,(inputBuffer+6)
       ld (numOutBytes),a
       ld a,(de)
       inc de
       ld hl,numOutBytes
       ld b,(hl)
       cp b
       jr nc,$F
       ld (numOutBytes),a
       jr $F
stringDescriptorReceived:
       ld a,(inputBuffer+2)                             ;***HACK - it should pull this from the API
       LOG StringDesc,a
       or a
       ld de,stringDescriptor
       jr z,descriptorReceived
       dec a
       ld de,manufacturerString
       jr z,descriptorReceived
       dec a
       jr nz,stallControlPipeEndHook
       ld de,productString
       in a,(21h)
       and 3
       jr z,descriptorReceived
       ld de,productStringSE
       jr descriptorReceived
configDescriptorReceived:
       ld a,(inputBuffer+6)
       ld (numOutBytes),a
       ld de,(configDescAddress)
       inc de
       inc de
       ld a,(de)
       dec de
       dec de
       ld hl,numOutBytes
       ld b,(hl)
       cp b
       jr nc,$F
       ld (numOutBytes),a
	jr $F
deviceDescriptorReceived:
       ld de,(deviceDescAddress)
descriptorReceived:
	ld a,(de)
	ld (numOutBytes),a
$$:    xor a
	out (8Eh),a
	ld a,40h
	out (91h),a
descriptorOutLoop:
	ld a,(numOutBytes)
	cp 40h
	jr c,$F
	ld b,40h                                         ;***HACK - bMaxPacketSize0 is hard-coded here
	sub b
	ld (numOutBytes),a
	jr continueOutput
$$:	ld b,a
	xor a
	ld (numOutBytes),a
continueOutput:
       push bc                                          ;***HACK - apparently the 40h command above needs a little delay sometimes
       ld bc,0FFh                                       ;        - the check on port 82h might be meaningless, but if it
$$:    ;in a,(82h)                                       ;             actually did succeed, the delay is no longer necessary
       ;bit 0,a                                          ;
       ;jr nz,$F                                         ;
       ex hl,(sp)                                       ;
       ex hl,(sp)                                       ;
       ex hl,(sp)                                       ;
       ex hl,(sp)                                       ;
       dec bc                                           ;
       ld a,b                                           ;
       or c                                             ;
       jr nz,$B                                         ;
$$:    pop bc                                           ;
$$:	ld a,(de)
	out (0A0h),a
	inc de
	djnz $B
	ld a,(numOutBytes)
	or a
	jr z,finishControlOutput
	xor a
	out (8Eh),a
	ld a,2
	out (91h),a
	jr descriptorOutLoop
setIdleRequest:
finishControlRequest:
       xor a
       out (8Eh),a
       in a,(91h)
       ld a,48h
       out (91h),a
       in a,(91h)
       jr cancelUSBHook
;--------------------------------------------------------------------------------------------------

;Bulk Requests
;--------------------------------------------------------------------------------------------------
bulkDataReady:
       ld a,2
       out (8Eh),a
       in a,(96h)
       LOG InData,a
       ld c,a                                                  ;might not need to do this
       ld b,0                                                  ;
       set 5,(iy+41h)
       set 0,(iy+41h)
       xor a
       out (5Bh),a
       ld (bytesRemaining),a
       ;Calculator bulk data received, deal with it
       ld hl,cancelUSBHook
       push hl
       ld hl,(callbackAddress)
       jp (hl)
;--------------------------------------------------------------------------------------------------

;String descriptors
stringDescriptor:
       DB 04h        ;size of descriptor
       DB 03h        ;string descriptor type
       DB 09h,04h    ;UNICODE string
manufacturerString:
       DB manufacturerStringEnd-manufacturerString
       DB 03h
       DB 'T',0,'e',0,'x',0,'a',0,'s',0,' ',0,'I',0,'n',0,'s',0,'t',0,'r',0,'u',0,'m',0,'e',0,'n',0,'t',0,'s',0,' ',0
       DB 'I',0,'n',0,'c',0,'o',0,'r',0,'p',0,'o',0,'r',0,'a',0,'t',0,'e',0,'d',0
manufacturerStringEnd:
productString:
       DB productStringEnd-productString
       DB 03h
       DB 'T',0,'I',0,'-',0,'8',0,'4',0,' ',0,'P',0,'l',0,'u',0,'s',0
productStringEnd:
productStringSE:
       DB productStringSEEnd-productStringSE
       DB 03h
       DB 'T',0,'I',0,'-',0,'8',0,'4',0,' ',0,'P',0,'l',0,'u',0,'s',0,' ',0
       DB 'S',0,'i',0,'l',0,'v',0,'e',0,'r',0,' ',0,'E',0,'d',0,'i',0,'t',0,'i',0,'o',0,'n',0
productStringSEEnd: