keyspan_pda.s

基于S3CEB2410平台LINUX操作系统下 USB驱动源代码

	addc a, dph
	mov dph, a		; dph = desc_strings[a]. big endian! (handy)
	;; it looks like my adapter uses a revision of the EZUSB that
	;; contains "rev D errata number 8", as hinted in the EzUSB example
	;; code. I cannot find an actual errata description on the Cypress
	;; web site, but from the example code it looks like this bug causes
	;; the length of string descriptors to be read incorrectly, possibly
	;; sending back more characters than the descriptor has. The workaround
	;; is to manually send out all of the data. The consequence of not
	;; using the workaround is that the strings gathered by the kernel
	;; driver are too long and are filled with trailing garbage (including
	;; leftover strings). Writing this out by hand is a nuisance, so for
	;; now I will just live with the bug.
	movx a, @dptr
	mov r1, a
	inc dptr
	movx a, @dptr
	mov r2, a
	mov dptr, SUDPTRH
	mov a, r1
	movx @dptr, a
	mov dptr, SUDPTRL
	mov a, r2
	movx @dptr, a
	;; done
	ljmp setup_done_ack
	
setup_Get_Descriptor_not_string:
	ljmp setup_stall
	
setup_breq_not_06:
	cjne r2, #0x08, setup_breq_not_08
	;; Get_Configuration. always 1. return one byte.
	;; this is reusable
	mov a, #1
setup_return_one_byte:	
	mov dptr, IN0BUF
	movx @dptr, a
	mov a, #1
	mov dptr, IN0BC
	movx @dptr, a
	ljmp setup_done_ack
setup_breq_not_08:
	cjne r2, #0x09, setup_breq_not_09
	;; 09: Set_Configuration. ignored.
	ljmp setup_done_ack
setup_breq_not_09:
	cjne r2, #0x0a, setup_breq_not_0a
	;; 0a: Get_Interface. get the current altsetting for int[wIndexL]
	;;  since we only have one interface, ignore wIndexL, return a 0
	mov a, #0
	ljmp setup_return_one_byte
setup_breq_not_0a:
	cjne r2, #0x0b, setup_breq_not_0b
	;; 0b: Set_Interface. set altsetting for interface[wIndexL]. ignored
	ljmp setup_done_ack
setup_breq_not_0b:
	ljmp setup_stall

		
setup_done_ack:	
	;; now clear HSNAK
	mov dptr, EP0CS
	mov a, #0x02
	movx @dptr, a
	sjmp setup_done
setup_stall:	
	;; unhandled. STALL
	;EP0CS |= bmEPSTALL
	mov dptr, EP0CS
	movx a, @dptr
	orl a, EP0STALLbit
	movx @dptr, a
	sjmp setup_done
	
setup_done:	
	pop acc
	pop dph1
	pop dpl1
	pop dph
	pop dpl
	pop dps
	reti

;;; ==============================================================
	
set_baud:			; baud index in r3
	;; verify a < 10
	mov a, r3
	jb ACC.7, set_baud__badbaud
	clr c
	subb a, #10
	jnc set_baud__badbaud
	mov a, r3
	rl a			; a = index*2
	add a, #LOW(baud_table)
	mov dpl, a
	mov a, #HIGH(baud_table)
	addc a, #0
	mov dph, a
	;; TODO: shut down xmit/receive
	;; TODO: wait for current xmit char to leave
	;; TODO: shut down timer to avoid partial-char glitch
	movx a,@dptr		; BAUD_HIGH
	mov RCAP2H, a
	mov TH2, a
	inc dptr
	movx a,@dptr		; BAUD_LOW
	mov RCAP2L, a
	mov TL2, a
	;; TODO: restart xmit/receive
	;; TODO: reenable interrupts, resume tx if pending
	clr c			; c=0: success
	ret
set_baud__badbaud:
	setb c			; c=1: failure
	ret
	
;;; ==================================================
control_pins:
	cjne r1, #0x41, control_pins_in
control_pins_out:
	mov a, r3 ; wValue[0] holds new bits:	b7 is new DTR, b2 is new RTS
	xrl a, #0xff		; 1 means active, 0V, +12V ?
	anl a, #0x84
	mov r3, a
	mov dptr, OUTC
	movx a, @dptr		; only change bits 7 and 2
	anl a, #0x7b		; ~0x84
	orl a, r3
	movx @dptr, a		; other pins are inputs, bits ignored
	ljmp setup_done_ack
control_pins_in:
	mov dptr, PINSC
	movx a, @dptr
	xrl a, #0xff
	ljmp setup_return_one_byte

;;; ========================================
	
ISR_Ep2in:
	push dps
	push dpl
	push dph
	push dpl1
	push dph1
	push acc
	mov a,EXIF
	clr acc.4
	mov EXIF,a		; clear INT2 first
	mov dptr, IN07IRQ	; clear USB int
	mov a,#04h
	movx @dptr,a

	;; do stuff
	lcall start_in
	
	pop acc
	pop dph1
	pop dpl1
	pop dph
	pop dpl
	pop dps
	reti

ISR_Ep2out:
	push dps
	push dpl
	push dph
	push dpl1
	push dph1
	push acc
	mov a,EXIF
	clr acc.4
	mov EXIF,a		; clear INT2 first
	mov dptr, OUT07IRQ	; clear USB int
	mov a,#04h
	movx @dptr,a

	;; do stuff

	;; copy data into buffer. for now, assume we will have enough space
	mov dptr, OUT2BC	; get byte count
	movx a,@dptr
	mov r1, a
	clr a
	mov dps, a
	mov dptr, OUT2BUF	; load DPTR0 with source
	mov dph1, #HIGH(tx_ring)	; load DPTR1 with target
	mov dpl1, tx_ring_in
OUT_loop:
	movx a,@dptr		; read
	inc dps			; switch to DPTR1: target
	inc dpl1		; target = tx_ring_in+1
	movx @dptr,a		; store
	mov a,dpl1
	cjne a, tx_ring_out, OUT_no_overflow
	sjmp OUT_overflow
OUT_no_overflow:	
	inc tx_ring_in		; tx_ring_in++
	inc dps			; switch to DPTR0: source
	inc dptr
	djnz r1, OUT_loop
	sjmp OUT_done
OUT_overflow:
	;; signal overflow
	;; fall through
OUT_done:	
	;; ack
	mov dptr,OUT2BC
	movx @dptr,a

	;; start tx
	acall maybe_start_tx
	;acall dump_stat
	
	pop acc
	pop dph1
	pop dpl1
	pop dph
	pop dpl
	pop dps
	reti

dump_stat:
	;; fill in EP4in with a debugging message:
	;;   tx_ring_in, tx_ring_out, rx_ring_in, rx_ring_out
	;;   tx_active
	;;   tx_ring[0..15]
	;;   0xfc
	;;   rx_ring[0..15]
	clr a
	mov dps, a
	
	mov dptr, IN4CS
	movx a, @dptr
	jb acc.1, dump_stat__done; busy: cannot dump, old one still pending
	mov dptr, IN4BUF
	
	mov a, tx_ring_in
	movx @dptr, a
	inc dptr
	mov a, tx_ring_out
	movx @dptr, a
	inc dptr

	mov a, rx_ring_in
	movx @dptr, a
	inc dptr
	mov a, rx_ring_out
	movx @dptr, a
	inc dptr
	
	clr a
	jnb TX_RUNNING, dump_stat__no_tx_running
	inc a
dump_stat__no_tx_running:
	movx @dptr, a
	inc dptr
	;; tx_ring[0..15]
	inc dps
	mov dptr, #tx_ring	; DPTR1: source
	mov r1, #16
dump_stat__tx_ring_loop:
	movx a, @dptr
	inc dptr
	inc dps
	movx @dptr, a
	inc dptr
	inc dps
	djnz r1, dump_stat__tx_ring_loop
	inc dps
	
	mov a, #0xfc
	movx @dptr, a
	inc dptr
	
	;; rx_ring[0..15]
	inc dps
	mov dptr, #rx_ring	; DPTR1: source
	mov r1, #16
dump_stat__rx_ring_loop:
	movx a, @dptr
	inc dptr
	inc dps
	movx @dptr, a
	inc dptr
	inc dps
	djnz r1, dump_stat__rx_ring_loop
	
	;; now send it
	clr a
	mov dps, a
	mov dptr, IN4BC
	mov a, #38
	movx @dptr, a
dump_stat__done:	
	ret
		
;;; ============================================================
	
maybe_start_tx:
	;; make sure the tx process is running.
	jb TX_RUNNING, start_tx_done
start_tx:
	;; is there work to be done?
	mov a, tx_ring_in
	cjne a,tx_ring_out, start_tx__work
	ret			; no work
start_tx__work:	
	;; tx was not running. send the first character, setup the TI int
	inc tx_ring_out		; [++tx_ring_out]
	mov dph, #HIGH(tx_ring)
	mov dpl, tx_ring_out
	movx a, @dptr
	mov sbuf, a
	setb TX_RUNNING
start_tx_done:
	;; can we unthrottle the host tx process?
	;;  step 1: do we care?
	mov a, #0
	cjne a, tx_unthrottle_threshold, start_tx__maybe_unthrottle_tx
	;; nope
start_tx_really_done:
	ret
start_tx__maybe_unthrottle_tx:
	;;  step 2: is there now room?
	mov a, tx_ring_out
	setb c
	subb a, tx_ring_in
	;; a is now write_room. If thresh >= a, we can unthrottle
	clr c
	subb a, tx_unthrottle_threshold
	jc start_tx_really_done	; nope
	;; yes, we can unthrottle. remove the threshold and mark a request
	mov tx_unthrottle_threshold, #0
	setb DO_TX_UNTHROTTLE
	;; prod rx, which will actually send the message when in2 becomes free
	ljmp start_in
	

serial_int:
	push dps
	push dpl
	push dph
	push dpl1
	push dph1
	push acc
	jnb TI, serial_int__not_tx
	;; tx finished. send another character if we have one
	clr TI			; clear int
	clr TX_RUNNING
	lcall start_tx
serial_int__not_tx:
	jnb RI, serial_int__not_rx
	lcall get_rx_char
	clr RI			; clear int
serial_int__not_rx:	
	;; return
	pop acc
	pop dph1
	pop dpl1
	pop dph
	pop dpl
	pop dps
	reti

get_rx_char:
	mov dph, #HIGH(rx_ring)
	mov dpl, rx_ring_in
	inc dpl			; target = rx_ring_in+1
	mov a, sbuf
	movx @dptr, a
	;; check for overflow before incrementing rx_ring_in
	mov a, dpl
	cjne a, rx_ring_out, get_rx_char__no_overflow
	;; signal overflow
	ret
get_rx_char__no_overflow:	
	inc rx_ring_in
	;; kick off USB INpipe
	acall start_in
	ret

start_in:
	;; check if the inpipe is already running.
	mov dptr, IN2CS
	movx a, @dptr
	jb acc.1, start_in__done; int will handle it
	jb DO_TX_UNTHROTTLE, start_in__do_tx_unthrottle
	;; see if there is any work to do. a serial interrupt might occur
	;; during this sequence?
	mov a, rx_ring_in
	cjne a, rx_ring_out, start_in__have_work
	ret			; nope
start_in__have_work:	
	;; now copy as much data as possible into the pipe. 63 bytes max.
	clr a
	mov dps, a
	mov dph, #HIGH(rx_ring)	; load DPTR0 with source
	inc dps
	mov dptr, IN2BUF	; load DPTR1 with target
	movx @dptr, a		; in[0] signals that rest of IN is rx data
	inc dptr
	inc dps
	;; loop until we run out of data, or we have copied 64 bytes
	mov r1, #1		; INbuf size counter
start_in__loop:
	mov a, rx_ring_in
	cjne a, rx_ring_out, start_in__still_copying
	sjmp start_in__kick
start_in__still_copying:
	inc rx_ring_out
	mov dpl, rx_ring_out
	movx a, @dptr
	inc dps
	movx @dptr, a		; write into IN buffer
	inc dptr
	inc dps
	inc r1
	cjne r1, #64, start_in__loop; loop
start_in__kick:
	;; either we ran out of data, or we copied 64 bytes. r1 has byte count
	;; kick off IN
	mov dptr, IN2BC
	mov a, r1
	jz start_in__done
	movx @dptr, a
	;; done
start_in__done:
	;acall dump_stat
	ret
start_in__do_tx_unthrottle:
	;; special sequence: send a tx unthrottle message
	clr DO_TX_UNTHROTTLE
	clr a
	mov dps, a
	mov dptr, IN2BUF
	mov a, #1
	movx @dptr, a
	inc dptr
	mov a, #2
	movx @dptr, a
	mov dptr, IN2BC
	movx @dptr, a
	ret
	
putchar:
	clr TI
	mov SBUF, a
putchar_wait:
	jnb TI, putchar_wait
	clr TI
	ret

	
baud_table:			; baud_high, then baud_low
	;; baud[0]: 110
	.byte BAUD_HIGH(110)
	.byte BAUD_LOW(110)
	;; baud[1]: 300
	.byte BAUD_HIGH(300)
	.byte BAUD_LOW(300)
	;; baud[2]: 1200
	.byte BAUD_HIGH(1200)
	.byte BAUD_LOW(1200)
	;; baud[3]: 2400
	.byte BAUD_HIGH(2400)
	.byte BAUD_LOW(2400)
	;; baud[4]: 4800
	.byte BAUD_HIGH(4800)
	.byte BAUD_LOW(4800)
	;; baud[5]: 9600
	.byte BAUD_HIGH(9600)
	.byte BAUD_LOW(9600)
	;; baud[6]: 19200
	.byte BAUD_HIGH(19200)
	.byte BAUD_LOW(19200)
	;; baud[7]: 38400
	.byte BAUD_HIGH(38400)
	.byte BAUD_LOW(38400)
	;; baud[8]: 57600
	.byte BAUD_HIGH(57600)
	.byte BAUD_LOW(57600)
	;; baud[9]: 115200
	.byte BAUD_HIGH(115200)
	.byte BAUD_LOW(115200)

desc_device:
	.byte 0x12, 0x01, 0x00, 0x01, 0xff, 0xff, 0xff, 0x40
	.byte 0xcd, 0x06, 0x04, 0x01, 0x89, 0xab, 1, 2, 3, 0x01
;;; The "real" device id, which must match the host driver, is that
;;; "0xcd 0x06 0x04 0x01" sequence, which is 0x06cd, 0x0104
	
desc_config1:
	.byte 0x09, 0x02, 0x20, 0x00, 0x01, 0x01, 0x00, 0x80, 0x32
	.byte 0x09, 0x04, 0x00, 0x00, 0x02, 0xff, 0xff, 0xff, 0x00
	.byte 0x07, 0x05, 0x82, 0x03, 0x40, 0x00, 0x01
	.byte 0x07, 0x05, 0x02, 0x02, 0x40, 0x00, 0x00

desc_strings:
	.word string_langids, string_mfg, string_product, string_serial
desc_strings_end:

string_langids:	.byte string_langids_end-string_langids
	.byte 3
	.word 0
string_langids_end:

	;; sigh. These strings are Unicode, meaning UTF16? 2 bytes each. Now
	;; *that* is a pain in the ass to encode. And they are little-endian
	;; too. Use this perl snippet to get the bytecodes:
	/* while (<>) {
	    @c = split(//);
	    foreach $c (@c) {
	     printf("0x%02x, 0x00, ", ord($c));
	    }
	   }
	*/

string_mfg:	.byte string_mfg_end-string_mfg
	.byte 3
;	.byte "ACME usb widgets"
	.byte 0x41, 0x00, 0x43, 0x00, 0x4d, 0x00, 0x45, 0x00, 0x20, 0x00, 0x75, 0x00, 0x73, 0x00, 0x62, 0x00, 0x20, 0x00, 0x77, 0x00, 0x69, 0x00, 0x64, 0x00, 0x67, 0x00, 0x65, 0x00, 0x74, 0x00, 0x73, 0x00
string_mfg_end:
	
string_product:	.byte string_product_end-string_product
	.byte 3
;	.byte "ACME USB serial widget"
	.byte 0x41, 0x00, 0x43, 0x00, 0x4d, 0x00, 0x45, 0x00, 0x20, 0x00, 0x55, 0x00, 0x53, 0x00, 0x42, 0x00, 0x20, 0x00, 0x73, 0x00, 0x65, 0x00, 0x72, 0x00, 0x69, 0x00, 0x61, 0x00, 0x6c, 0x00, 0x20, 0x00, 0x77, 0x00, 0x69, 0x00, 0x64, 0x00, 0x67, 0x00, 0x65, 0x00, 0x74, 0x00
string_product_end:
	
string_serial:	.byte string_serial_end-string_serial
	.byte 3
;	.byte "47"
	.byte 0x34, 0x00, 0x37, 0x00
string_serial_end:
		
;;; ring buffer memory
	;; tx_ring_in+1 is where the next input byte will go
	;; [tx_ring_out] has been sent
	;; if tx_ring_in == tx_ring_out, theres no work to do
	;; there are (tx_ring_in - tx_ring_out) chars to be written
	;; dont let _in lap _out
	;;   cannot inc if tx_ring_in+1 == tx_ring_out
	;;  write [tx_ring_in+1] then tx_ring_in++
	;;   if (tx_ring_in+1 == tx_ring_out), overflow
	;;   else tx_ring_in++
	;;  read/send [tx_ring_out+1], then tx_ring_out++

	;; rx_ring_in works the same way
	
	.org 0x1000
tx_ring:
	.skip 0x100		; 256 bytes
rx_ring:
	.skip 0x100		; 256 bytes
	
	
	.END