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path: root/drivers/isdn/hisax/st5481_hdlc.c
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Diffstat (limited to 'drivers/isdn/hisax/st5481_hdlc.c')
-rw-r--r--drivers/isdn/hisax/st5481_hdlc.c580
1 files changed, 0 insertions, 580 deletions
diff --git a/drivers/isdn/hisax/st5481_hdlc.c b/drivers/isdn/hisax/st5481_hdlc.c
deleted file mode 100644
index 680f42e9a993..000000000000
--- a/drivers/isdn/hisax/st5481_hdlc.c
+++ /dev/null
@@ -1,580 +0,0 @@
-/*
- * Driver for ST5481 USB ISDN modem
- *
- * Author Frode Isaksen
- * Copyright 2001 by Frode Isaksen <fisaksen@bewan.com>
- * 2001 by Kai Germaschewski <kai.germaschewski@gmx.de>
- *
- * This software may be used and distributed according to the terms
- * of the GNU General Public License, incorporated herein by reference.
- *
- */
-
-#include <linux/crc-ccitt.h>
-#include "st5481_hdlc.h"
-
-
-enum {
- HDLC_FAST_IDLE,HDLC_GET_FLAG_B0,HDLC_GETFLAG_B1A6,HDLC_GETFLAG_B7,
- HDLC_GET_DATA,HDLC_FAST_FLAG
-};
-
-enum {
- HDLC_SEND_DATA,HDLC_SEND_CRC1,HDLC_SEND_FAST_FLAG,
- HDLC_SEND_FIRST_FLAG,HDLC_SEND_CRC2,HDLC_SEND_CLOSING_FLAG,
- HDLC_SEND_IDLE1,HDLC_SEND_FAST_IDLE,HDLC_SENDFLAG_B0,
- HDLC_SENDFLAG_B1A6,HDLC_SENDFLAG_B7,STOPPED
-};
-
-void
-hdlc_rcv_init(struct hdlc_vars *hdlc, int do_adapt56)
-{
- hdlc->bit_shift = 0;
- hdlc->hdlc_bits1 = 0;
- hdlc->data_bits = 0;
- hdlc->ffbit_shift = 0;
- hdlc->data_received = 0;
- hdlc->state = HDLC_GET_DATA;
- hdlc->do_adapt56 = do_adapt56;
- hdlc->dchannel = 0;
- hdlc->crc = 0;
- hdlc->cbin = 0;
- hdlc->shift_reg = 0;
- hdlc->ffvalue = 0;
- hdlc->dstpos = 0;
-}
-
-void
-hdlc_out_init(struct hdlc_vars *hdlc, int is_d_channel, int do_adapt56)
-{
- hdlc->bit_shift = 0;
- hdlc->hdlc_bits1 = 0;
- hdlc->data_bits = 0;
- hdlc->ffbit_shift = 0;
- hdlc->data_received = 0;
- hdlc->do_closing = 0;
- hdlc->ffvalue = 0;
- if (is_d_channel) {
- hdlc->dchannel = 1;
- hdlc->state = HDLC_SEND_FIRST_FLAG;
- } else {
- hdlc->dchannel = 0;
- hdlc->state = HDLC_SEND_FAST_FLAG;
- hdlc->ffvalue = 0x7e;
- }
- hdlc->cbin = 0x7e;
- hdlc->bit_shift = 0;
- if(do_adapt56){
- hdlc->do_adapt56 = 1;
- hdlc->data_bits = 0;
- hdlc->state = HDLC_SENDFLAG_B0;
- } else {
- hdlc->do_adapt56 = 0;
- hdlc->data_bits = 8;
- }
- hdlc->shift_reg = 0;
-}
-
-/*
- hdlc_decode - decodes HDLC frames from a transparent bit stream.
-
- The source buffer is scanned for valid HDLC frames looking for
- flags (01111110) to indicate the start of a frame. If the start of
- the frame is found, the bit stuffing is removed (0 after 5 1's).
- When a new flag is found, the complete frame has been received
- and the CRC is checked.
- If a valid frame is found, the function returns the frame length
- excluding the CRC with the bit HDLC_END_OF_FRAME set.
- If the beginning of a valid frame is found, the function returns
- the length.
- If a framing error is found (too many 1s and not a flag) the function
- returns the length with the bit HDLC_FRAMING_ERROR set.
- If a CRC error is found the function returns the length with the
- bit HDLC_CRC_ERROR set.
- If the frame length exceeds the destination buffer size, the function
- returns the length with the bit HDLC_LENGTH_ERROR set.
-
- src - source buffer
- slen - source buffer length
- count - number of bytes removed (decoded) from the source buffer
- dst _ destination buffer
- dsize - destination buffer size
- returns - number of decoded bytes in the destination buffer and status
- flag.
- */
-int hdlc_decode(struct hdlc_vars *hdlc, const unsigned char *src,
- int slen, int *count, unsigned char *dst, int dsize)
-{
- int status=0;
-
- static const unsigned char fast_flag[]={
- 0x00,0x00,0x00,0x20,0x30,0x38,0x3c,0x3e,0x3f
- };
-
- static const unsigned char fast_flag_value[]={
- 0x00,0x7e,0xfc,0xf9,0xf3,0xe7,0xcf,0x9f,0x3f
- };
-
- static const unsigned char fast_abort[]={
- 0x00,0x00,0x80,0xc0,0xe0,0xf0,0xf8,0xfc,0xfe,0xff
- };
-
- *count = slen;
-
- while(slen > 0){
- if(hdlc->bit_shift==0){
- hdlc->cbin = *src++;
- slen--;
- hdlc->bit_shift = 8;
- if(hdlc->do_adapt56){
- hdlc->bit_shift --;
- }
- }
-
- switch(hdlc->state){
- case STOPPED:
- return 0;
- case HDLC_FAST_IDLE:
- if(hdlc->cbin == 0xff){
- hdlc->bit_shift = 0;
- break;
- }
- hdlc->state = HDLC_GET_FLAG_B0;
- hdlc->hdlc_bits1 = 0;
- hdlc->bit_shift = 8;
- break;
- case HDLC_GET_FLAG_B0:
- if(!(hdlc->cbin & 0x80)) {
- hdlc->state = HDLC_GETFLAG_B1A6;
- hdlc->hdlc_bits1 = 0;
- } else {
- if(!hdlc->do_adapt56){
- if(++hdlc->hdlc_bits1 >=8 ) if(hdlc->bit_shift==1)
- hdlc->state = HDLC_FAST_IDLE;
- }
- }
- hdlc->cbin<<=1;
- hdlc->bit_shift --;
- break;
- case HDLC_GETFLAG_B1A6:
- if(hdlc->cbin & 0x80){
- hdlc->hdlc_bits1++;
- if(hdlc->hdlc_bits1==6){
- hdlc->state = HDLC_GETFLAG_B7;
- }
- } else {
- hdlc->hdlc_bits1 = 0;
- }
- hdlc->cbin<<=1;
- hdlc->bit_shift --;
- break;
- case HDLC_GETFLAG_B7:
- if(hdlc->cbin & 0x80) {
- hdlc->state = HDLC_GET_FLAG_B0;
- } else {
- hdlc->state = HDLC_GET_DATA;
- hdlc->crc = 0xffff;
- hdlc->shift_reg = 0;
- hdlc->hdlc_bits1 = 0;
- hdlc->data_bits = 0;
- hdlc->data_received = 0;
- }
- hdlc->cbin<<=1;
- hdlc->bit_shift --;
- break;
- case HDLC_GET_DATA:
- if(hdlc->cbin & 0x80){
- hdlc->hdlc_bits1++;
- switch(hdlc->hdlc_bits1){
- case 6:
- break;
- case 7:
- if(hdlc->data_received) {
- // bad frame
- status = -HDLC_FRAMING_ERROR;
- }
- if(!hdlc->do_adapt56){
- if(hdlc->cbin==fast_abort[hdlc->bit_shift+1]){
- hdlc->state = HDLC_FAST_IDLE;
- hdlc->bit_shift=1;
- break;
- }
- } else {
- hdlc->state = HDLC_GET_FLAG_B0;
- }
- break;
- default:
- hdlc->shift_reg>>=1;
- hdlc->shift_reg |= 0x80;
- hdlc->data_bits++;
- break;
- }
- } else {
- switch(hdlc->hdlc_bits1){
- case 5:
- break;
- case 6:
- if(hdlc->data_received){
- if (hdlc->dstpos < 2) {
- status = -HDLC_FRAMING_ERROR;
- } else if (hdlc->crc != 0xf0b8){
- // crc error
- status = -HDLC_CRC_ERROR;
- } else {
- // remove CRC
- hdlc->dstpos -= 2;
- // good frame
- status = hdlc->dstpos;
- }
- }
- hdlc->crc = 0xffff;
- hdlc->shift_reg = 0;
- hdlc->data_bits = 0;
- if(!hdlc->do_adapt56){
- if(hdlc->cbin==fast_flag[hdlc->bit_shift]){
- hdlc->ffvalue = fast_flag_value[hdlc->bit_shift];
- hdlc->state = HDLC_FAST_FLAG;
- hdlc->ffbit_shift = hdlc->bit_shift;
- hdlc->bit_shift = 1;
- } else {
- hdlc->state = HDLC_GET_DATA;
- hdlc->data_received = 0;
- }
- } else {
- hdlc->state = HDLC_GET_DATA;
- hdlc->data_received = 0;
- }
- break;
- default:
- hdlc->shift_reg>>=1;
- hdlc->data_bits++;
- break;
- }
- hdlc->hdlc_bits1 = 0;
- }
- if (status) {
- hdlc->dstpos = 0;
- *count -= slen;
- hdlc->cbin <<= 1;
- hdlc->bit_shift--;
- return status;
- }
- if(hdlc->data_bits==8){
- hdlc->data_bits = 0;
- hdlc->data_received = 1;
- hdlc->crc = crc_ccitt_byte(hdlc->crc, hdlc->shift_reg);
-
- // good byte received
- if (dsize--) {
- dst[hdlc->dstpos++] = hdlc->shift_reg;
- } else {
- // frame too long
- status = -HDLC_LENGTH_ERROR;
- hdlc->dstpos = 0;
- }
- }
- hdlc->cbin <<= 1;
- hdlc->bit_shift--;
- break;
- case HDLC_FAST_FLAG:
- if(hdlc->cbin==hdlc->ffvalue){
- hdlc->bit_shift = 0;
- break;
- } else {
- if(hdlc->cbin == 0xff){
- hdlc->state = HDLC_FAST_IDLE;
- hdlc->bit_shift=0;
- } else if(hdlc->ffbit_shift==8){
- hdlc->state = HDLC_GETFLAG_B7;
- break;
- } else {
- hdlc->shift_reg = fast_abort[hdlc->ffbit_shift-1];
- hdlc->hdlc_bits1 = hdlc->ffbit_shift-2;
- if(hdlc->hdlc_bits1<0)hdlc->hdlc_bits1 = 0;
- hdlc->data_bits = hdlc->ffbit_shift-1;
- hdlc->state = HDLC_GET_DATA;
- hdlc->data_received = 0;
- }
- }
- break;
- default:
- break;
- }
- }
- *count -= slen;
- return 0;
-}
-
-/*
- hdlc_encode - encodes HDLC frames to a transparent bit stream.
-
- The bit stream starts with a beginning flag (01111110). After
- that each byte is added to the bit stream with bit stuffing added
- (0 after 5 1's).
- When the last byte has been removed from the source buffer, the
- CRC (2 bytes is added) and the frame terminates with the ending flag.
- For the dchannel, the idle character (all 1's) is also added at the end.
- If this function is called with empty source buffer (slen=0), flags or
- idle character will be generated.
-
- src - source buffer
- slen - source buffer length
- count - number of bytes removed (encoded) from source buffer
- dst _ destination buffer
- dsize - destination buffer size
- returns - number of encoded bytes in the destination buffer
-*/
-int hdlc_encode(struct hdlc_vars *hdlc, const unsigned char *src,
- unsigned short slen, int *count,
- unsigned char *dst, int dsize)
-{
- static const unsigned char xfast_flag_value[] = {
- 0x7e,0x3f,0x9f,0xcf,0xe7,0xf3,0xf9,0xfc,0x7e
- };
-
- int len = 0;
-
- *count = slen;
-
- while (dsize > 0) {
- if(hdlc->bit_shift==0){
- if(slen && !hdlc->do_closing){
- hdlc->shift_reg = *src++;
- slen--;
- if (slen == 0)
- hdlc->do_closing = 1; /* closing sequence, CRC + flag(s) */
- hdlc->bit_shift = 8;
- } else {
- if(hdlc->state == HDLC_SEND_DATA){
- if(hdlc->data_received){
- hdlc->state = HDLC_SEND_CRC1;
- hdlc->crc ^= 0xffff;
- hdlc->bit_shift = 8;
- hdlc->shift_reg = hdlc->crc & 0xff;
- } else if(!hdlc->do_adapt56){
- hdlc->state = HDLC_SEND_FAST_FLAG;
- } else {
- hdlc->state = HDLC_SENDFLAG_B0;
- }
- }
-
- }
- }
-
- switch(hdlc->state){
- case STOPPED:
- while (dsize--)
- *dst++ = 0xff;
-
- return dsize;
- case HDLC_SEND_FAST_FLAG:
- hdlc->do_closing = 0;
- if(slen == 0){
- *dst++ = hdlc->ffvalue;
- len++;
- dsize--;
- break;
- }
- if(hdlc->bit_shift==8){
- hdlc->cbin = hdlc->ffvalue>>(8-hdlc->data_bits);
- hdlc->state = HDLC_SEND_DATA;
- hdlc->crc = 0xffff;
- hdlc->hdlc_bits1 = 0;
- hdlc->data_received = 1;
- }
- break;
- case HDLC_SENDFLAG_B0:
- hdlc->do_closing = 0;
- hdlc->cbin <<= 1;
- hdlc->data_bits++;
- hdlc->hdlc_bits1 = 0;
- hdlc->state = HDLC_SENDFLAG_B1A6;
- break;
- case HDLC_SENDFLAG_B1A6:
- hdlc->cbin <<= 1;
- hdlc->data_bits++;
- hdlc->cbin++;
- if(++hdlc->hdlc_bits1 == 6)
- hdlc->state = HDLC_SENDFLAG_B7;
- break;
- case HDLC_SENDFLAG_B7:
- hdlc->cbin <<= 1;
- hdlc->data_bits++;
- if(slen == 0){
- hdlc->state = HDLC_SENDFLAG_B0;
- break;
- }
- if(hdlc->bit_shift==8){
- hdlc->state = HDLC_SEND_DATA;
- hdlc->crc = 0xffff;
- hdlc->hdlc_bits1 = 0;
- hdlc->data_received = 1;
- }
- break;
- case HDLC_SEND_FIRST_FLAG:
- hdlc->data_received = 1;
- if(hdlc->data_bits==8){
- hdlc->state = HDLC_SEND_DATA;
- hdlc->crc = 0xffff;
- hdlc->hdlc_bits1 = 0;
- break;
- }
- hdlc->cbin <<= 1;
- hdlc->data_bits++;
- if(hdlc->shift_reg & 0x01)
- hdlc->cbin++;
- hdlc->shift_reg >>= 1;
- hdlc->bit_shift--;
- if(hdlc->bit_shift==0){
- hdlc->state = HDLC_SEND_DATA;
- hdlc->crc = 0xffff;
- hdlc->hdlc_bits1 = 0;
- }
- break;
- case HDLC_SEND_DATA:
- hdlc->cbin <<= 1;
- hdlc->data_bits++;
- if(hdlc->hdlc_bits1 == 5){
- hdlc->hdlc_bits1 = 0;
- break;
- }
- if(hdlc->bit_shift==8){
- hdlc->crc = crc_ccitt_byte(hdlc->crc, hdlc->shift_reg);
- }
- if(hdlc->shift_reg & 0x01){
- hdlc->hdlc_bits1++;
- hdlc->cbin++;
- hdlc->shift_reg >>= 1;
- hdlc->bit_shift--;
- } else {
- hdlc->hdlc_bits1 = 0;
- hdlc->shift_reg >>= 1;
- hdlc->bit_shift--;
- }
- break;
- case HDLC_SEND_CRC1:
- hdlc->cbin <<= 1;
- hdlc->data_bits++;
- if(hdlc->hdlc_bits1 == 5){
- hdlc->hdlc_bits1 = 0;
- break;
- }
- if(hdlc->shift_reg & 0x01){
- hdlc->hdlc_bits1++;
- hdlc->cbin++;
- hdlc->shift_reg >>= 1;
- hdlc->bit_shift--;
- } else {
- hdlc->hdlc_bits1 = 0;
- hdlc->shift_reg >>= 1;
- hdlc->bit_shift--;
- }
- if(hdlc->bit_shift==0){
- hdlc->shift_reg = (hdlc->crc >> 8);
- hdlc->state = HDLC_SEND_CRC2;
- hdlc->bit_shift = 8;
- }
- break;
- case HDLC_SEND_CRC2:
- hdlc->cbin <<= 1;
- hdlc->data_bits++;
- if(hdlc->hdlc_bits1 == 5){
- hdlc->hdlc_bits1 = 0;
- break;
- }
- if(hdlc->shift_reg & 0x01){
- hdlc->hdlc_bits1++;
- hdlc->cbin++;
- hdlc->shift_reg >>= 1;
- hdlc->bit_shift--;
- } else {
- hdlc->hdlc_bits1 = 0;
- hdlc->shift_reg >>= 1;
- hdlc->bit_shift--;
- }
- if(hdlc->bit_shift==0){
- hdlc->shift_reg = 0x7e;
- hdlc->state = HDLC_SEND_CLOSING_FLAG;
- hdlc->bit_shift = 8;
- }
- break;
- case HDLC_SEND_CLOSING_FLAG:
- hdlc->cbin <<= 1;
- hdlc->data_bits++;
- if(hdlc->hdlc_bits1 == 5){
- hdlc->hdlc_bits1 = 0;
- break;
- }
- if(hdlc->shift_reg & 0x01){
- hdlc->cbin++;
- }
- hdlc->shift_reg >>= 1;
- hdlc->bit_shift--;
- if(hdlc->bit_shift==0){
- hdlc->ffvalue = xfast_flag_value[hdlc->data_bits];
- if(hdlc->dchannel){
- hdlc->ffvalue = 0x7e;
- hdlc->state = HDLC_SEND_IDLE1;
- hdlc->bit_shift = 8-hdlc->data_bits;
- if(hdlc->bit_shift==0)
- hdlc->state = HDLC_SEND_FAST_IDLE;
- } else {
- if(!hdlc->do_adapt56){
- hdlc->state = HDLC_SEND_FAST_FLAG;
- hdlc->data_received = 0;
- } else {
- hdlc->state = HDLC_SENDFLAG_B0;
- hdlc->data_received = 0;
- }
- // Finished with this frame, send flags
- if (dsize > 1) dsize = 1;
- }
- }
- break;
- case HDLC_SEND_IDLE1:
- hdlc->do_closing = 0;
- hdlc->cbin <<= 1;
- hdlc->cbin++;
- hdlc->data_bits++;
- hdlc->bit_shift--;
- if(hdlc->bit_shift==0){
- hdlc->state = HDLC_SEND_FAST_IDLE;
- hdlc->bit_shift = 0;
- }
- break;
- case HDLC_SEND_FAST_IDLE:
- hdlc->do_closing = 0;
- hdlc->cbin = 0xff;
- hdlc->data_bits = 8;
- if(hdlc->bit_shift == 8){
- hdlc->cbin = 0x7e;
- hdlc->state = HDLC_SEND_FIRST_FLAG;
- } else {
- *dst++ = hdlc->cbin;
- hdlc->bit_shift = hdlc->data_bits = 0;
- len++;
- dsize = 0;
- }
- break;
- default:
- break;
- }
- if(hdlc->do_adapt56){
- if(hdlc->data_bits==7){
- hdlc->cbin <<= 1;
- hdlc->cbin++;
- hdlc->data_bits++;
- }
- }
- if(hdlc->data_bits==8){
- *dst++ = hdlc->cbin;
- hdlc->data_bits = 0;
- len++;
- dsize--;
- }
- }
- *count -= slen;
-
- return len;
-}
-
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-17 21:02:55 +0300