02137f2e80
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: Karsten Keil <kkeil@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
1012 lines
36 KiB
C
1012 lines
36 KiB
C
/*
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* Common data handling layer for bas_gigaset
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*
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* Copyright (c) 2005 by Tilman Schmidt <tilman@imap.cc>,
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* Hansjoerg Lipp <hjlipp@web.de>.
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*
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* =====================================================================
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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* =====================================================================
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*/
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#include "gigaset.h"
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#include <linux/crc-ccitt.h>
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#include <linux/bitrev.h>
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/* access methods for isowbuf_t */
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/* ============================ */
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/* initialize buffer structure
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*/
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void gigaset_isowbuf_init(struct isowbuf_t *iwb, unsigned char idle)
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{
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iwb->read = 0;
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iwb->nextread = 0;
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iwb->write = 0;
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atomic_set(&iwb->writesem, 1);
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iwb->wbits = 0;
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iwb->idle = idle;
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memset(iwb->data + BAS_OUTBUFSIZE, idle, BAS_OUTBUFPAD);
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}
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/* compute number of bytes which can be appended to buffer
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* so that there is still room to append a maximum frame of flags
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*/
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static inline int isowbuf_freebytes(struct isowbuf_t *iwb)
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{
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int read, write, freebytes;
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read = iwb->read;
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write = iwb->write;
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if ((freebytes = read - write) > 0) {
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/* no wraparound: need padding space within regular area */
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return freebytes - BAS_OUTBUFPAD;
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} else if (read < BAS_OUTBUFPAD) {
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/* wraparound: can use space up to end of regular area */
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return BAS_OUTBUFSIZE - write;
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} else {
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/* following the wraparound yields more space */
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return freebytes + BAS_OUTBUFSIZE - BAS_OUTBUFPAD;
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}
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}
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/* compare two offsets within the buffer
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* The buffer is seen as circular, with the read position as start
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* returns -1/0/1 if position a </=/> position b without crossing 'read'
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*/
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static inline int isowbuf_poscmp(struct isowbuf_t *iwb, int a, int b)
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{
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int read;
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if (a == b)
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return 0;
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read = iwb->read;
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if (a < b) {
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if (a < read && read <= b)
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return +1;
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else
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return -1;
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} else {
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if (b < read && read <= a)
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return -1;
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else
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return +1;
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}
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}
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/* start writing
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* acquire the write semaphore
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* return true if acquired, false if busy
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*/
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static inline int isowbuf_startwrite(struct isowbuf_t *iwb)
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{
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if (!atomic_dec_and_test(&iwb->writesem)) {
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atomic_inc(&iwb->writesem);
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gig_dbg(DEBUG_ISO, "%s: couldn't acquire iso write semaphore",
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__func__);
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return 0;
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}
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#ifdef CONFIG_GIGASET_DEBUG
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gig_dbg(DEBUG_ISO,
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"%s: acquired iso write semaphore, data[write]=%02x, nbits=%d",
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__func__, iwb->data[iwb->write], iwb->wbits);
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#endif
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return 1;
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}
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/* finish writing
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* release the write semaphore
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* returns the current write position
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*/
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static inline int isowbuf_donewrite(struct isowbuf_t *iwb)
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{
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int write = iwb->write;
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atomic_inc(&iwb->writesem);
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return write;
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}
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/* append bits to buffer without any checks
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* - data contains bits to append, starting at LSB
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* - nbits is number of bits to append (0..24)
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* must be called with the write semaphore held
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* If more than nbits bits are set in data, the extraneous bits are set in the
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* buffer too, but the write position is only advanced by nbits.
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*/
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static inline void isowbuf_putbits(struct isowbuf_t *iwb, u32 data, int nbits)
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{
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int write = iwb->write;
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data <<= iwb->wbits;
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data |= iwb->data[write];
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nbits += iwb->wbits;
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while (nbits >= 8) {
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iwb->data[write++] = data & 0xff;
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write %= BAS_OUTBUFSIZE;
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data >>= 8;
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nbits -= 8;
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}
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iwb->wbits = nbits;
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iwb->data[write] = data & 0xff;
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iwb->write = write;
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}
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/* put final flag on HDLC bitstream
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* also sets the idle fill byte to the correspondingly shifted flag pattern
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* must be called with the write semaphore held
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*/
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static inline void isowbuf_putflag(struct isowbuf_t *iwb)
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{
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int write;
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/* add two flags, thus reliably covering one byte */
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isowbuf_putbits(iwb, 0x7e7e, 8);
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/* recover the idle flag byte */
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write = iwb->write;
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iwb->idle = iwb->data[write];
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gig_dbg(DEBUG_ISO, "idle fill byte %02x", iwb->idle);
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/* mask extraneous bits in buffer */
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iwb->data[write] &= (1 << iwb->wbits) - 1;
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}
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/* retrieve a block of bytes for sending
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* The requested number of bytes is provided as a contiguous block.
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* If necessary, the frame is filled to the requested number of bytes
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* with the idle value.
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* returns offset to frame, < 0 on busy or error
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*/
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int gigaset_isowbuf_getbytes(struct isowbuf_t *iwb, int size)
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{
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int read, write, limit, src, dst;
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unsigned char pbyte;
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read = iwb->nextread;
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write = iwb->write;
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if (likely(read == write)) {
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/* return idle frame */
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return read < BAS_OUTBUFPAD ?
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BAS_OUTBUFSIZE : read - BAS_OUTBUFPAD;
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}
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limit = read + size;
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gig_dbg(DEBUG_STREAM, "%s: read=%d write=%d limit=%d",
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__func__, read, write, limit);
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#ifdef CONFIG_GIGASET_DEBUG
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if (unlikely(size < 0 || size > BAS_OUTBUFPAD)) {
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err("invalid size %d", size);
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return -EINVAL;
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}
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src = iwb->read;
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if (unlikely(limit > BAS_OUTBUFSIZE + BAS_OUTBUFPAD ||
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(read < src && limit >= src))) {
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err("isoc write buffer frame reservation violated");
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return -EFAULT;
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}
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#endif
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if (read < write) {
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/* no wraparound in valid data */
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if (limit >= write) {
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/* append idle frame */
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if (!isowbuf_startwrite(iwb))
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return -EBUSY;
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/* write position could have changed */
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write = iwb->write;
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if (limit >= write) {
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pbyte = iwb->data[write]; /* save
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partial byte */
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limit = write + BAS_OUTBUFPAD;
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gig_dbg(DEBUG_STREAM,
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"%s: filling %d->%d with %02x",
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__func__, write, limit, iwb->idle);
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if (write + BAS_OUTBUFPAD < BAS_OUTBUFSIZE)
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memset(iwb->data + write, iwb->idle,
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BAS_OUTBUFPAD);
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else {
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/* wraparound, fill entire pad area */
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memset(iwb->data + write, iwb->idle,
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BAS_OUTBUFSIZE + BAS_OUTBUFPAD
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- write);
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limit = 0;
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}
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gig_dbg(DEBUG_STREAM,
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"%s: restoring %02x at %d",
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__func__, pbyte, limit);
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iwb->data[limit] = pbyte; /* restore
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partial byte */
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iwb->write = limit;
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}
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isowbuf_donewrite(iwb);
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}
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} else {
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/* valid data wraparound */
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if (limit >= BAS_OUTBUFSIZE) {
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/* copy wrapped part into pad area */
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src = 0;
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dst = BAS_OUTBUFSIZE;
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while (dst < limit && src < write)
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iwb->data[dst++] = iwb->data[src++];
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if (dst <= limit) {
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/* fill pad area with idle byte */
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memset(iwb->data + dst, iwb->idle,
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BAS_OUTBUFSIZE + BAS_OUTBUFPAD - dst);
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}
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limit = src;
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}
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}
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iwb->nextread = limit;
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return read;
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}
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/* dump_bytes
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* write hex bytes to syslog for debugging
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*/
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static inline void dump_bytes(enum debuglevel level, const char *tag,
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unsigned char *bytes, int count)
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{
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#ifdef CONFIG_GIGASET_DEBUG
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unsigned char c;
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static char dbgline[3 * 32 + 1];
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int i = 0;
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while (count-- > 0) {
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if (i > sizeof(dbgline) - 4) {
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dbgline[i] = '\0';
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gig_dbg(level, "%s:%s", tag, dbgline);
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i = 0;
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}
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c = *bytes++;
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dbgline[i] = (i && !(i % 12)) ? '-' : ' ';
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i++;
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dbgline[i++] = hex_asc_hi(c);
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dbgline[i++] = hex_asc_lo(c);
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}
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dbgline[i] = '\0';
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gig_dbg(level, "%s:%s", tag, dbgline);
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#endif
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}
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/*============================================================================*/
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/* bytewise HDLC bitstuffing via table lookup
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* lookup table: 5 subtables for 0..4 preceding consecutive '1' bits
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* index: 256*(number of preceding '1' bits) + (next byte to stuff)
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* value: bit 9.. 0 = result bits
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* bit 12..10 = number of trailing '1' bits in result
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* bit 14..13 = number of bits added by stuffing
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*/
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static const u16 stufftab[5 * 256] = {
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// previous 1s = 0:
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0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007, 0x0008, 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x000f,
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0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x0017, 0x0018, 0x0019, 0x001a, 0x001b, 0x001c, 0x001d, 0x001e, 0x201f,
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0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027, 0x0028, 0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x002f,
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0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x0037, 0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x203e, 0x205f,
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0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x0047, 0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x004f,
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0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x0057, 0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x209f,
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0x0060, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x0067, 0x0068, 0x0069, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x006f,
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0x0070, 0x0071, 0x0072, 0x0073, 0x0074, 0x0075, 0x0076, 0x0077, 0x0078, 0x0079, 0x007a, 0x007b, 0x207c, 0x207d, 0x20be, 0x20df,
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0x0480, 0x0481, 0x0482, 0x0483, 0x0484, 0x0485, 0x0486, 0x0487, 0x0488, 0x0489, 0x048a, 0x048b, 0x048c, 0x048d, 0x048e, 0x048f,
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0x0490, 0x0491, 0x0492, 0x0493, 0x0494, 0x0495, 0x0496, 0x0497, 0x0498, 0x0499, 0x049a, 0x049b, 0x049c, 0x049d, 0x049e, 0x251f,
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0x04a0, 0x04a1, 0x04a2, 0x04a3, 0x04a4, 0x04a5, 0x04a6, 0x04a7, 0x04a8, 0x04a9, 0x04aa, 0x04ab, 0x04ac, 0x04ad, 0x04ae, 0x04af,
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0x04b0, 0x04b1, 0x04b2, 0x04b3, 0x04b4, 0x04b5, 0x04b6, 0x04b7, 0x04b8, 0x04b9, 0x04ba, 0x04bb, 0x04bc, 0x04bd, 0x253e, 0x255f,
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0x08c0, 0x08c1, 0x08c2, 0x08c3, 0x08c4, 0x08c5, 0x08c6, 0x08c7, 0x08c8, 0x08c9, 0x08ca, 0x08cb, 0x08cc, 0x08cd, 0x08ce, 0x08cf,
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0x08d0, 0x08d1, 0x08d2, 0x08d3, 0x08d4, 0x08d5, 0x08d6, 0x08d7, 0x08d8, 0x08d9, 0x08da, 0x08db, 0x08dc, 0x08dd, 0x08de, 0x299f,
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0x0ce0, 0x0ce1, 0x0ce2, 0x0ce3, 0x0ce4, 0x0ce5, 0x0ce6, 0x0ce7, 0x0ce8, 0x0ce9, 0x0cea, 0x0ceb, 0x0cec, 0x0ced, 0x0cee, 0x0cef,
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0x10f0, 0x10f1, 0x10f2, 0x10f3, 0x10f4, 0x10f5, 0x10f6, 0x10f7, 0x20f8, 0x20f9, 0x20fa, 0x20fb, 0x257c, 0x257d, 0x29be, 0x2ddf,
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// previous 1s = 1:
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0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007, 0x0008, 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x200f,
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0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x0017, 0x0018, 0x0019, 0x001a, 0x001b, 0x001c, 0x001d, 0x001e, 0x202f,
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0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027, 0x0028, 0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x204f,
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0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x0037, 0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x203e, 0x206f,
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0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x0047, 0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x208f,
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0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x0057, 0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x20af,
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0x0060, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x0067, 0x0068, 0x0069, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x20cf,
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0x0070, 0x0071, 0x0072, 0x0073, 0x0074, 0x0075, 0x0076, 0x0077, 0x0078, 0x0079, 0x007a, 0x007b, 0x207c, 0x207d, 0x20be, 0x20ef,
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0x0480, 0x0481, 0x0482, 0x0483, 0x0484, 0x0485, 0x0486, 0x0487, 0x0488, 0x0489, 0x048a, 0x048b, 0x048c, 0x048d, 0x048e, 0x250f,
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0x0490, 0x0491, 0x0492, 0x0493, 0x0494, 0x0495, 0x0496, 0x0497, 0x0498, 0x0499, 0x049a, 0x049b, 0x049c, 0x049d, 0x049e, 0x252f,
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0x04a0, 0x04a1, 0x04a2, 0x04a3, 0x04a4, 0x04a5, 0x04a6, 0x04a7, 0x04a8, 0x04a9, 0x04aa, 0x04ab, 0x04ac, 0x04ad, 0x04ae, 0x254f,
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0x04b0, 0x04b1, 0x04b2, 0x04b3, 0x04b4, 0x04b5, 0x04b6, 0x04b7, 0x04b8, 0x04b9, 0x04ba, 0x04bb, 0x04bc, 0x04bd, 0x253e, 0x256f,
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0x08c0, 0x08c1, 0x08c2, 0x08c3, 0x08c4, 0x08c5, 0x08c6, 0x08c7, 0x08c8, 0x08c9, 0x08ca, 0x08cb, 0x08cc, 0x08cd, 0x08ce, 0x298f,
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0x08d0, 0x08d1, 0x08d2, 0x08d3, 0x08d4, 0x08d5, 0x08d6, 0x08d7, 0x08d8, 0x08d9, 0x08da, 0x08db, 0x08dc, 0x08dd, 0x08de, 0x29af,
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0x0ce0, 0x0ce1, 0x0ce2, 0x0ce3, 0x0ce4, 0x0ce5, 0x0ce6, 0x0ce7, 0x0ce8, 0x0ce9, 0x0cea, 0x0ceb, 0x0cec, 0x0ced, 0x0cee, 0x2dcf,
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0x10f0, 0x10f1, 0x10f2, 0x10f3, 0x10f4, 0x10f5, 0x10f6, 0x10f7, 0x20f8, 0x20f9, 0x20fa, 0x20fb, 0x257c, 0x257d, 0x29be, 0x31ef,
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// previous 1s = 2:
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0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x2007, 0x0008, 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x2017,
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0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x2027, 0x0018, 0x0019, 0x001a, 0x001b, 0x001c, 0x001d, 0x001e, 0x2037,
|
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0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x2047, 0x0028, 0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x2057,
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0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x2067, 0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x203e, 0x2077,
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0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x2087, 0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x2097,
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0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x20a7, 0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x20b7,
|
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0x0060, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x20c7, 0x0068, 0x0069, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x20d7,
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0x0070, 0x0071, 0x0072, 0x0073, 0x0074, 0x0075, 0x0076, 0x20e7, 0x0078, 0x0079, 0x007a, 0x007b, 0x207c, 0x207d, 0x20be, 0x20f7,
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0x0480, 0x0481, 0x0482, 0x0483, 0x0484, 0x0485, 0x0486, 0x2507, 0x0488, 0x0489, 0x048a, 0x048b, 0x048c, 0x048d, 0x048e, 0x2517,
|
|
0x0490, 0x0491, 0x0492, 0x0493, 0x0494, 0x0495, 0x0496, 0x2527, 0x0498, 0x0499, 0x049a, 0x049b, 0x049c, 0x049d, 0x049e, 0x2537,
|
|
0x04a0, 0x04a1, 0x04a2, 0x04a3, 0x04a4, 0x04a5, 0x04a6, 0x2547, 0x04a8, 0x04a9, 0x04aa, 0x04ab, 0x04ac, 0x04ad, 0x04ae, 0x2557,
|
|
0x04b0, 0x04b1, 0x04b2, 0x04b3, 0x04b4, 0x04b5, 0x04b6, 0x2567, 0x04b8, 0x04b9, 0x04ba, 0x04bb, 0x04bc, 0x04bd, 0x253e, 0x2577,
|
|
0x08c0, 0x08c1, 0x08c2, 0x08c3, 0x08c4, 0x08c5, 0x08c6, 0x2987, 0x08c8, 0x08c9, 0x08ca, 0x08cb, 0x08cc, 0x08cd, 0x08ce, 0x2997,
|
|
0x08d0, 0x08d1, 0x08d2, 0x08d3, 0x08d4, 0x08d5, 0x08d6, 0x29a7, 0x08d8, 0x08d9, 0x08da, 0x08db, 0x08dc, 0x08dd, 0x08de, 0x29b7,
|
|
0x0ce0, 0x0ce1, 0x0ce2, 0x0ce3, 0x0ce4, 0x0ce5, 0x0ce6, 0x2dc7, 0x0ce8, 0x0ce9, 0x0cea, 0x0ceb, 0x0cec, 0x0ced, 0x0cee, 0x2dd7,
|
|
0x10f0, 0x10f1, 0x10f2, 0x10f3, 0x10f4, 0x10f5, 0x10f6, 0x31e7, 0x20f8, 0x20f9, 0x20fa, 0x20fb, 0x257c, 0x257d, 0x29be, 0x41f7,
|
|
|
|
// previous 1s = 3:
|
|
0x0000, 0x0001, 0x0002, 0x2003, 0x0004, 0x0005, 0x0006, 0x200b, 0x0008, 0x0009, 0x000a, 0x2013, 0x000c, 0x000d, 0x000e, 0x201b,
|
|
0x0010, 0x0011, 0x0012, 0x2023, 0x0014, 0x0015, 0x0016, 0x202b, 0x0018, 0x0019, 0x001a, 0x2033, 0x001c, 0x001d, 0x001e, 0x203b,
|
|
0x0020, 0x0021, 0x0022, 0x2043, 0x0024, 0x0025, 0x0026, 0x204b, 0x0028, 0x0029, 0x002a, 0x2053, 0x002c, 0x002d, 0x002e, 0x205b,
|
|
0x0030, 0x0031, 0x0032, 0x2063, 0x0034, 0x0035, 0x0036, 0x206b, 0x0038, 0x0039, 0x003a, 0x2073, 0x003c, 0x003d, 0x203e, 0x207b,
|
|
0x0040, 0x0041, 0x0042, 0x2083, 0x0044, 0x0045, 0x0046, 0x208b, 0x0048, 0x0049, 0x004a, 0x2093, 0x004c, 0x004d, 0x004e, 0x209b,
|
|
0x0050, 0x0051, 0x0052, 0x20a3, 0x0054, 0x0055, 0x0056, 0x20ab, 0x0058, 0x0059, 0x005a, 0x20b3, 0x005c, 0x005d, 0x005e, 0x20bb,
|
|
0x0060, 0x0061, 0x0062, 0x20c3, 0x0064, 0x0065, 0x0066, 0x20cb, 0x0068, 0x0069, 0x006a, 0x20d3, 0x006c, 0x006d, 0x006e, 0x20db,
|
|
0x0070, 0x0071, 0x0072, 0x20e3, 0x0074, 0x0075, 0x0076, 0x20eb, 0x0078, 0x0079, 0x007a, 0x20f3, 0x207c, 0x207d, 0x20be, 0x40fb,
|
|
0x0480, 0x0481, 0x0482, 0x2503, 0x0484, 0x0485, 0x0486, 0x250b, 0x0488, 0x0489, 0x048a, 0x2513, 0x048c, 0x048d, 0x048e, 0x251b,
|
|
0x0490, 0x0491, 0x0492, 0x2523, 0x0494, 0x0495, 0x0496, 0x252b, 0x0498, 0x0499, 0x049a, 0x2533, 0x049c, 0x049d, 0x049e, 0x253b,
|
|
0x04a0, 0x04a1, 0x04a2, 0x2543, 0x04a4, 0x04a5, 0x04a6, 0x254b, 0x04a8, 0x04a9, 0x04aa, 0x2553, 0x04ac, 0x04ad, 0x04ae, 0x255b,
|
|
0x04b0, 0x04b1, 0x04b2, 0x2563, 0x04b4, 0x04b5, 0x04b6, 0x256b, 0x04b8, 0x04b9, 0x04ba, 0x2573, 0x04bc, 0x04bd, 0x253e, 0x257b,
|
|
0x08c0, 0x08c1, 0x08c2, 0x2983, 0x08c4, 0x08c5, 0x08c6, 0x298b, 0x08c8, 0x08c9, 0x08ca, 0x2993, 0x08cc, 0x08cd, 0x08ce, 0x299b,
|
|
0x08d0, 0x08d1, 0x08d2, 0x29a3, 0x08d4, 0x08d5, 0x08d6, 0x29ab, 0x08d8, 0x08d9, 0x08da, 0x29b3, 0x08dc, 0x08dd, 0x08de, 0x29bb,
|
|
0x0ce0, 0x0ce1, 0x0ce2, 0x2dc3, 0x0ce4, 0x0ce5, 0x0ce6, 0x2dcb, 0x0ce8, 0x0ce9, 0x0cea, 0x2dd3, 0x0cec, 0x0ced, 0x0cee, 0x2ddb,
|
|
0x10f0, 0x10f1, 0x10f2, 0x31e3, 0x10f4, 0x10f5, 0x10f6, 0x31eb, 0x20f8, 0x20f9, 0x20fa, 0x41f3, 0x257c, 0x257d, 0x29be, 0x46fb,
|
|
|
|
// previous 1s = 4:
|
|
0x0000, 0x2001, 0x0002, 0x2005, 0x0004, 0x2009, 0x0006, 0x200d, 0x0008, 0x2011, 0x000a, 0x2015, 0x000c, 0x2019, 0x000e, 0x201d,
|
|
0x0010, 0x2021, 0x0012, 0x2025, 0x0014, 0x2029, 0x0016, 0x202d, 0x0018, 0x2031, 0x001a, 0x2035, 0x001c, 0x2039, 0x001e, 0x203d,
|
|
0x0020, 0x2041, 0x0022, 0x2045, 0x0024, 0x2049, 0x0026, 0x204d, 0x0028, 0x2051, 0x002a, 0x2055, 0x002c, 0x2059, 0x002e, 0x205d,
|
|
0x0030, 0x2061, 0x0032, 0x2065, 0x0034, 0x2069, 0x0036, 0x206d, 0x0038, 0x2071, 0x003a, 0x2075, 0x003c, 0x2079, 0x203e, 0x407d,
|
|
0x0040, 0x2081, 0x0042, 0x2085, 0x0044, 0x2089, 0x0046, 0x208d, 0x0048, 0x2091, 0x004a, 0x2095, 0x004c, 0x2099, 0x004e, 0x209d,
|
|
0x0050, 0x20a1, 0x0052, 0x20a5, 0x0054, 0x20a9, 0x0056, 0x20ad, 0x0058, 0x20b1, 0x005a, 0x20b5, 0x005c, 0x20b9, 0x005e, 0x20bd,
|
|
0x0060, 0x20c1, 0x0062, 0x20c5, 0x0064, 0x20c9, 0x0066, 0x20cd, 0x0068, 0x20d1, 0x006a, 0x20d5, 0x006c, 0x20d9, 0x006e, 0x20dd,
|
|
0x0070, 0x20e1, 0x0072, 0x20e5, 0x0074, 0x20e9, 0x0076, 0x20ed, 0x0078, 0x20f1, 0x007a, 0x20f5, 0x207c, 0x40f9, 0x20be, 0x417d,
|
|
0x0480, 0x2501, 0x0482, 0x2505, 0x0484, 0x2509, 0x0486, 0x250d, 0x0488, 0x2511, 0x048a, 0x2515, 0x048c, 0x2519, 0x048e, 0x251d,
|
|
0x0490, 0x2521, 0x0492, 0x2525, 0x0494, 0x2529, 0x0496, 0x252d, 0x0498, 0x2531, 0x049a, 0x2535, 0x049c, 0x2539, 0x049e, 0x253d,
|
|
0x04a0, 0x2541, 0x04a2, 0x2545, 0x04a4, 0x2549, 0x04a6, 0x254d, 0x04a8, 0x2551, 0x04aa, 0x2555, 0x04ac, 0x2559, 0x04ae, 0x255d,
|
|
0x04b0, 0x2561, 0x04b2, 0x2565, 0x04b4, 0x2569, 0x04b6, 0x256d, 0x04b8, 0x2571, 0x04ba, 0x2575, 0x04bc, 0x2579, 0x253e, 0x467d,
|
|
0x08c0, 0x2981, 0x08c2, 0x2985, 0x08c4, 0x2989, 0x08c6, 0x298d, 0x08c8, 0x2991, 0x08ca, 0x2995, 0x08cc, 0x2999, 0x08ce, 0x299d,
|
|
0x08d0, 0x29a1, 0x08d2, 0x29a5, 0x08d4, 0x29a9, 0x08d6, 0x29ad, 0x08d8, 0x29b1, 0x08da, 0x29b5, 0x08dc, 0x29b9, 0x08de, 0x29bd,
|
|
0x0ce0, 0x2dc1, 0x0ce2, 0x2dc5, 0x0ce4, 0x2dc9, 0x0ce6, 0x2dcd, 0x0ce8, 0x2dd1, 0x0cea, 0x2dd5, 0x0cec, 0x2dd9, 0x0cee, 0x2ddd,
|
|
0x10f0, 0x31e1, 0x10f2, 0x31e5, 0x10f4, 0x31e9, 0x10f6, 0x31ed, 0x20f8, 0x41f1, 0x20fa, 0x41f5, 0x257c, 0x46f9, 0x29be, 0x4b7d
|
|
};
|
|
|
|
/* hdlc_bitstuff_byte
|
|
* perform HDLC bitstuffing for one input byte (8 bits, LSB first)
|
|
* parameters:
|
|
* cin input byte
|
|
* ones number of trailing '1' bits in result before this step
|
|
* iwb pointer to output buffer structure (write semaphore must be held)
|
|
* return value:
|
|
* number of trailing '1' bits in result after this step
|
|
*/
|
|
|
|
static inline int hdlc_bitstuff_byte(struct isowbuf_t *iwb, unsigned char cin,
|
|
int ones)
|
|
{
|
|
u16 stuff;
|
|
int shiftinc, newones;
|
|
|
|
/* get stuffing information for input byte
|
|
* value: bit 9.. 0 = result bits
|
|
* bit 12..10 = number of trailing '1' bits in result
|
|
* bit 14..13 = number of bits added by stuffing
|
|
*/
|
|
stuff = stufftab[256 * ones + cin];
|
|
shiftinc = (stuff >> 13) & 3;
|
|
newones = (stuff >> 10) & 7;
|
|
stuff &= 0x3ff;
|
|
|
|
/* append stuffed byte to output stream */
|
|
isowbuf_putbits(iwb, stuff, 8 + shiftinc);
|
|
return newones;
|
|
}
|
|
|
|
/* hdlc_buildframe
|
|
* Perform HDLC framing with bitstuffing on a byte buffer
|
|
* The input buffer is regarded as a sequence of bits, starting with the least
|
|
* significant bit of the first byte and ending with the most significant bit
|
|
* of the last byte. A 16 bit FCS is appended as defined by RFC 1662.
|
|
* Whenever five consecutive '1' bits appear in the resulting bit sequence, a
|
|
* '0' bit is inserted after them.
|
|
* The resulting bit string and a closing flag pattern (PPP_FLAG, '01111110')
|
|
* are appended to the output buffer starting at the given bit position, which
|
|
* is assumed to already contain a leading flag.
|
|
* The output buffer must have sufficient length; count + count/5 + 6 bytes
|
|
* starting at *out are safe and are verified to be present.
|
|
* parameters:
|
|
* in input buffer
|
|
* count number of bytes in input buffer
|
|
* iwb pointer to output buffer structure (write semaphore must be held)
|
|
* return value:
|
|
* position of end of packet in output buffer on success,
|
|
* -EAGAIN if write semaphore busy or buffer full
|
|
*/
|
|
|
|
static inline int hdlc_buildframe(struct isowbuf_t *iwb,
|
|
unsigned char *in, int count)
|
|
{
|
|
int ones;
|
|
u16 fcs;
|
|
int end;
|
|
unsigned char c;
|
|
|
|
if (isowbuf_freebytes(iwb) < count + count / 5 + 6 ||
|
|
!isowbuf_startwrite(iwb)) {
|
|
gig_dbg(DEBUG_ISO, "%s: %d bytes free -> -EAGAIN",
|
|
__func__, isowbuf_freebytes(iwb));
|
|
return -EAGAIN;
|
|
}
|
|
|
|
dump_bytes(DEBUG_STREAM, "snd data", in, count);
|
|
|
|
/* bitstuff and checksum input data */
|
|
fcs = PPP_INITFCS;
|
|
ones = 0;
|
|
while (count-- > 0) {
|
|
c = *in++;
|
|
ones = hdlc_bitstuff_byte(iwb, c, ones);
|
|
fcs = crc_ccitt_byte(fcs, c);
|
|
}
|
|
|
|
/* bitstuff and append FCS (complemented, least significant byte first) */
|
|
fcs ^= 0xffff;
|
|
ones = hdlc_bitstuff_byte(iwb, fcs & 0x00ff, ones);
|
|
ones = hdlc_bitstuff_byte(iwb, (fcs >> 8) & 0x00ff, ones);
|
|
|
|
/* put closing flag and repeat byte for flag idle */
|
|
isowbuf_putflag(iwb);
|
|
end = isowbuf_donewrite(iwb);
|
|
dump_bytes(DEBUG_STREAM_DUMP, "isowbuf", iwb->data, end + 1);
|
|
return end;
|
|
}
|
|
|
|
/* trans_buildframe
|
|
* Append a block of 'transparent' data to the output buffer,
|
|
* inverting the bytes.
|
|
* The output buffer must have sufficient length; count bytes
|
|
* starting at *out are safe and are verified to be present.
|
|
* parameters:
|
|
* in input buffer
|
|
* count number of bytes in input buffer
|
|
* iwb pointer to output buffer structure (write semaphore must be held)
|
|
* return value:
|
|
* position of end of packet in output buffer on success,
|
|
* -EAGAIN if write semaphore busy or buffer full
|
|
*/
|
|
|
|
static inline int trans_buildframe(struct isowbuf_t *iwb,
|
|
unsigned char *in, int count)
|
|
{
|
|
int write;
|
|
unsigned char c;
|
|
|
|
if (unlikely(count <= 0))
|
|
return iwb->write;
|
|
|
|
if (isowbuf_freebytes(iwb) < count ||
|
|
!isowbuf_startwrite(iwb)) {
|
|
gig_dbg(DEBUG_ISO, "can't put %d bytes", count);
|
|
return -EAGAIN;
|
|
}
|
|
|
|
gig_dbg(DEBUG_STREAM, "put %d bytes", count);
|
|
write = iwb->write;
|
|
do {
|
|
c = bitrev8(*in++);
|
|
iwb->data[write++] = c;
|
|
write %= BAS_OUTBUFSIZE;
|
|
} while (--count > 0);
|
|
iwb->write = write;
|
|
iwb->idle = c;
|
|
|
|
return isowbuf_donewrite(iwb);
|
|
}
|
|
|
|
int gigaset_isoc_buildframe(struct bc_state *bcs, unsigned char *in, int len)
|
|
{
|
|
int result;
|
|
|
|
switch (bcs->proto2) {
|
|
case ISDN_PROTO_L2_HDLC:
|
|
result = hdlc_buildframe(bcs->hw.bas->isooutbuf, in, len);
|
|
gig_dbg(DEBUG_ISO, "%s: %d bytes HDLC -> %d",
|
|
__func__, len, result);
|
|
break;
|
|
default: /* assume transparent */
|
|
result = trans_buildframe(bcs->hw.bas->isooutbuf, in, len);
|
|
gig_dbg(DEBUG_ISO, "%s: %d bytes trans -> %d",
|
|
__func__, len, result);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/* hdlc_putbyte
|
|
* append byte c to current skb of B channel structure *bcs, updating fcs
|
|
*/
|
|
static inline void hdlc_putbyte(unsigned char c, struct bc_state *bcs)
|
|
{
|
|
bcs->fcs = crc_ccitt_byte(bcs->fcs, c);
|
|
if (unlikely(bcs->skb == NULL)) {
|
|
/* skipping */
|
|
return;
|
|
}
|
|
if (unlikely(bcs->skb->len == SBUFSIZE)) {
|
|
dev_warn(bcs->cs->dev, "received oversized packet discarded\n");
|
|
bcs->hw.bas->giants++;
|
|
dev_kfree_skb_any(bcs->skb);
|
|
bcs->skb = NULL;
|
|
return;
|
|
}
|
|
*__skb_put(bcs->skb, 1) = c;
|
|
}
|
|
|
|
/* hdlc_flush
|
|
* drop partial HDLC data packet
|
|
*/
|
|
static inline void hdlc_flush(struct bc_state *bcs)
|
|
{
|
|
/* clear skb or allocate new if not skipping */
|
|
if (likely(bcs->skb != NULL))
|
|
skb_trim(bcs->skb, 0);
|
|
else if (!bcs->ignore) {
|
|
if ((bcs->skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN)) != NULL)
|
|
skb_reserve(bcs->skb, HW_HDR_LEN);
|
|
else
|
|
dev_err(bcs->cs->dev, "could not allocate skb\n");
|
|
}
|
|
|
|
/* reset packet state */
|
|
bcs->fcs = PPP_INITFCS;
|
|
}
|
|
|
|
/* hdlc_done
|
|
* process completed HDLC data packet
|
|
*/
|
|
static inline void hdlc_done(struct bc_state *bcs)
|
|
{
|
|
struct sk_buff *procskb;
|
|
|
|
if (unlikely(bcs->ignore)) {
|
|
bcs->ignore--;
|
|
hdlc_flush(bcs);
|
|
return;
|
|
}
|
|
|
|
if ((procskb = bcs->skb) == NULL) {
|
|
/* previous error */
|
|
gig_dbg(DEBUG_ISO, "%s: skb=NULL", __func__);
|
|
gigaset_rcv_error(NULL, bcs->cs, bcs);
|
|
} else if (procskb->len < 2) {
|
|
dev_notice(bcs->cs->dev, "received short frame (%d octets)\n",
|
|
procskb->len);
|
|
bcs->hw.bas->runts++;
|
|
gigaset_rcv_error(procskb, bcs->cs, bcs);
|
|
} else if (bcs->fcs != PPP_GOODFCS) {
|
|
dev_notice(bcs->cs->dev, "frame check error (0x%04x)\n",
|
|
bcs->fcs);
|
|
bcs->hw.bas->fcserrs++;
|
|
gigaset_rcv_error(procskb, bcs->cs, bcs);
|
|
} else {
|
|
procskb->len -= 2; /* subtract FCS */
|
|
procskb->tail -= 2;
|
|
gig_dbg(DEBUG_ISO, "%s: good frame (%d octets)",
|
|
__func__, procskb->len);
|
|
dump_bytes(DEBUG_STREAM,
|
|
"rcv data", procskb->data, procskb->len);
|
|
bcs->hw.bas->goodbytes += procskb->len;
|
|
gigaset_rcv_skb(procskb, bcs->cs, bcs);
|
|
}
|
|
|
|
if ((bcs->skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN)) != NULL)
|
|
skb_reserve(bcs->skb, HW_HDR_LEN);
|
|
else
|
|
dev_err(bcs->cs->dev, "could not allocate skb\n");
|
|
bcs->fcs = PPP_INITFCS;
|
|
}
|
|
|
|
/* hdlc_frag
|
|
* drop HDLC data packet with non-integral last byte
|
|
*/
|
|
static inline void hdlc_frag(struct bc_state *bcs, unsigned inbits)
|
|
{
|
|
if (unlikely(bcs->ignore)) {
|
|
bcs->ignore--;
|
|
hdlc_flush(bcs);
|
|
return;
|
|
}
|
|
|
|
dev_notice(bcs->cs->dev, "received partial byte (%d bits)\n", inbits);
|
|
bcs->hw.bas->alignerrs++;
|
|
gigaset_rcv_error(bcs->skb, bcs->cs, bcs);
|
|
|
|
if ((bcs->skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN)) != NULL)
|
|
skb_reserve(bcs->skb, HW_HDR_LEN);
|
|
else
|
|
dev_err(bcs->cs->dev, "could not allocate skb\n");
|
|
bcs->fcs = PPP_INITFCS;
|
|
}
|
|
|
|
/* bit counts lookup table for HDLC bit unstuffing
|
|
* index: input byte
|
|
* value: bit 0..3 = number of consecutive '1' bits starting from LSB
|
|
* bit 4..6 = number of consecutive '1' bits starting from MSB
|
|
* (replacing 8 by 7 to make it fit; the algorithm won't care)
|
|
* bit 7 set if there are 5 or more "interior" consecutive '1' bits
|
|
*/
|
|
static const unsigned char bitcounts[256] = {
|
|
0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x04,
|
|
0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x05,
|
|
0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x04,
|
|
0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x80, 0x06,
|
|
0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x04,
|
|
0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x05,
|
|
0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x04,
|
|
0x00, 0x01, 0x00, 0x02, 0x00, 0x01, 0x00, 0x03, 0x00, 0x01, 0x00, 0x02, 0x80, 0x81, 0x80, 0x07,
|
|
0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x13, 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x14,
|
|
0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x13, 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x15,
|
|
0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x13, 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x14,
|
|
0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x10, 0x13, 0x10, 0x11, 0x10, 0x12, 0x10, 0x11, 0x90, 0x16,
|
|
0x20, 0x21, 0x20, 0x22, 0x20, 0x21, 0x20, 0x23, 0x20, 0x21, 0x20, 0x22, 0x20, 0x21, 0x20, 0x24,
|
|
0x20, 0x21, 0x20, 0x22, 0x20, 0x21, 0x20, 0x23, 0x20, 0x21, 0x20, 0x22, 0x20, 0x21, 0x20, 0x25,
|
|
0x30, 0x31, 0x30, 0x32, 0x30, 0x31, 0x30, 0x33, 0x30, 0x31, 0x30, 0x32, 0x30, 0x31, 0x30, 0x34,
|
|
0x40, 0x41, 0x40, 0x42, 0x40, 0x41, 0x40, 0x43, 0x50, 0x51, 0x50, 0x52, 0x60, 0x61, 0x70, 0x78
|
|
};
|
|
|
|
/* hdlc_unpack
|
|
* perform HDLC frame processing (bit unstuffing, flag detection, FCS calculation)
|
|
* on a sequence of received data bytes (8 bits each, LSB first)
|
|
* pass on successfully received, complete frames as SKBs via gigaset_rcv_skb
|
|
* notify of errors via gigaset_rcv_error
|
|
* tally frames, errors etc. in BC structure counters
|
|
* parameters:
|
|
* src received data
|
|
* count number of received bytes
|
|
* bcs receiving B channel structure
|
|
*/
|
|
static inline void hdlc_unpack(unsigned char *src, unsigned count,
|
|
struct bc_state *bcs)
|
|
{
|
|
struct bas_bc_state *ubc = bcs->hw.bas;
|
|
int inputstate;
|
|
unsigned seqlen, inbyte, inbits;
|
|
|
|
/* load previous state:
|
|
* inputstate = set of flag bits:
|
|
* - INS_flag_hunt: no complete opening flag received since connection setup or last abort
|
|
* - INS_have_data: at least one complete data byte received since last flag
|
|
* seqlen = number of consecutive '1' bits in last 7 input stream bits (0..7)
|
|
* inbyte = accumulated partial data byte (if !INS_flag_hunt)
|
|
* inbits = number of valid bits in inbyte, starting at LSB (0..6)
|
|
*/
|
|
inputstate = bcs->inputstate;
|
|
seqlen = ubc->seqlen;
|
|
inbyte = ubc->inbyte;
|
|
inbits = ubc->inbits;
|
|
|
|
/* bit unstuffing a byte a time
|
|
* Take your time to understand this; it's straightforward but tedious.
|
|
* The "bitcounts" lookup table is used to speed up the counting of
|
|
* leading and trailing '1' bits.
|
|
*/
|
|
while (count--) {
|
|
unsigned char c = *src++;
|
|
unsigned char tabentry = bitcounts[c];
|
|
unsigned lead1 = tabentry & 0x0f;
|
|
unsigned trail1 = (tabentry >> 4) & 0x0f;
|
|
|
|
seqlen += lead1;
|
|
|
|
if (unlikely(inputstate & INS_flag_hunt)) {
|
|
if (c == PPP_FLAG) {
|
|
/* flag-in-one */
|
|
inputstate &= ~(INS_flag_hunt | INS_have_data);
|
|
inbyte = 0;
|
|
inbits = 0;
|
|
} else if (seqlen == 6 && trail1 != 7) {
|
|
/* flag completed & not followed by abort */
|
|
inputstate &= ~(INS_flag_hunt | INS_have_data);
|
|
inbyte = c >> (lead1 + 1);
|
|
inbits = 7 - lead1;
|
|
if (trail1 >= 8) {
|
|
/* interior stuffing: omitting the MSB handles most cases */
|
|
inbits--;
|
|
/* correct the incorrectly handled cases individually */
|
|
switch (c) {
|
|
case 0xbe:
|
|
inbyte = 0x3f;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
/* else: continue flag-hunting */
|
|
} else if (likely(seqlen < 5 && trail1 < 7)) {
|
|
/* streamlined case: 8 data bits, no stuffing */
|
|
inbyte |= c << inbits;
|
|
hdlc_putbyte(inbyte & 0xff, bcs);
|
|
inputstate |= INS_have_data;
|
|
inbyte >>= 8;
|
|
/* inbits unchanged */
|
|
} else if (likely(seqlen == 6 && inbits == 7 - lead1 &&
|
|
trail1 + 1 == inbits &&
|
|
!(inputstate & INS_have_data))) {
|
|
/* streamlined case: flag idle - state unchanged */
|
|
} else if (unlikely(seqlen > 6)) {
|
|
/* abort sequence */
|
|
ubc->aborts++;
|
|
hdlc_flush(bcs);
|
|
inputstate |= INS_flag_hunt;
|
|
} else if (seqlen == 6) {
|
|
/* closing flag, including (6 - lead1) '1's and one '0' from inbits */
|
|
if (inbits > 7 - lead1) {
|
|
hdlc_frag(bcs, inbits + lead1 - 7);
|
|
inputstate &= ~INS_have_data;
|
|
} else {
|
|
if (inbits < 7 - lead1)
|
|
ubc->stolen0s ++;
|
|
if (inputstate & INS_have_data) {
|
|
hdlc_done(bcs);
|
|
inputstate &= ~INS_have_data;
|
|
}
|
|
}
|
|
|
|
if (c == PPP_FLAG) {
|
|
/* complete flag, LSB overlaps preceding flag */
|
|
ubc->shared0s ++;
|
|
inbits = 0;
|
|
inbyte = 0;
|
|
} else if (trail1 != 7) {
|
|
/* remaining bits */
|
|
inbyte = c >> (lead1 + 1);
|
|
inbits = 7 - lead1;
|
|
if (trail1 >= 8) {
|
|
/* interior stuffing: omitting the MSB handles most cases */
|
|
inbits--;
|
|
/* correct the incorrectly handled cases individually */
|
|
switch (c) {
|
|
case 0xbe:
|
|
inbyte = 0x3f;
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
/* abort sequence follows, skb already empty anyway */
|
|
ubc->aborts++;
|
|
inputstate |= INS_flag_hunt;
|
|
}
|
|
} else { /* (seqlen < 6) && (seqlen == 5 || trail1 >= 7) */
|
|
|
|
if (c == PPP_FLAG) {
|
|
/* complete flag */
|
|
if (seqlen == 5)
|
|
ubc->stolen0s++;
|
|
if (inbits) {
|
|
hdlc_frag(bcs, inbits);
|
|
inbits = 0;
|
|
inbyte = 0;
|
|
} else if (inputstate & INS_have_data)
|
|
hdlc_done(bcs);
|
|
inputstate &= ~INS_have_data;
|
|
} else if (trail1 == 7) {
|
|
/* abort sequence */
|
|
ubc->aborts++;
|
|
hdlc_flush(bcs);
|
|
inputstate |= INS_flag_hunt;
|
|
} else {
|
|
/* stuffed data */
|
|
if (trail1 < 7) { /* => seqlen == 5 */
|
|
/* stuff bit at position lead1, no interior stuffing */
|
|
unsigned char mask = (1 << lead1) - 1;
|
|
c = (c & mask) | ((c & ~mask) >> 1);
|
|
inbyte |= c << inbits;
|
|
inbits += 7;
|
|
} else if (seqlen < 5) { /* trail1 >= 8 */
|
|
/* interior stuffing: omitting the MSB handles most cases */
|
|
/* correct the incorrectly handled cases individually */
|
|
switch (c) {
|
|
case 0xbe:
|
|
c = 0x7e;
|
|
break;
|
|
}
|
|
inbyte |= c << inbits;
|
|
inbits += 7;
|
|
} else { /* seqlen == 5 && trail1 >= 8 */
|
|
|
|
/* stuff bit at lead1 *and* interior stuffing */
|
|
switch (c) { /* unstuff individually */
|
|
case 0x7d:
|
|
c = 0x3f;
|
|
break;
|
|
case 0xbe:
|
|
c = 0x3f;
|
|
break;
|
|
case 0x3e:
|
|
c = 0x1f;
|
|
break;
|
|
case 0x7c:
|
|
c = 0x3e;
|
|
break;
|
|
}
|
|
inbyte |= c << inbits;
|
|
inbits += 6;
|
|
}
|
|
if (inbits >= 8) {
|
|
inbits -= 8;
|
|
hdlc_putbyte(inbyte & 0xff, bcs);
|
|
inputstate |= INS_have_data;
|
|
inbyte >>= 8;
|
|
}
|
|
}
|
|
}
|
|
seqlen = trail1 & 7;
|
|
}
|
|
|
|
/* save new state */
|
|
bcs->inputstate = inputstate;
|
|
ubc->seqlen = seqlen;
|
|
ubc->inbyte = inbyte;
|
|
ubc->inbits = inbits;
|
|
}
|
|
|
|
/* trans_receive
|
|
* pass on received USB frame transparently as SKB via gigaset_rcv_skb
|
|
* invert bytes
|
|
* tally frames, errors etc. in BC structure counters
|
|
* parameters:
|
|
* src received data
|
|
* count number of received bytes
|
|
* bcs receiving B channel structure
|
|
*/
|
|
static inline void trans_receive(unsigned char *src, unsigned count,
|
|
struct bc_state *bcs)
|
|
{
|
|
struct sk_buff *skb;
|
|
int dobytes;
|
|
unsigned char *dst;
|
|
|
|
if (unlikely(bcs->ignore)) {
|
|
bcs->ignore--;
|
|
hdlc_flush(bcs);
|
|
return;
|
|
}
|
|
if (unlikely((skb = bcs->skb) == NULL)) {
|
|
bcs->skb = skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN);
|
|
if (!skb) {
|
|
dev_err(bcs->cs->dev, "could not allocate skb\n");
|
|
return;
|
|
}
|
|
skb_reserve(skb, HW_HDR_LEN);
|
|
}
|
|
bcs->hw.bas->goodbytes += skb->len;
|
|
dobytes = TRANSBUFSIZE - skb->len;
|
|
while (count > 0) {
|
|
dst = skb_put(skb, count < dobytes ? count : dobytes);
|
|
while (count > 0 && dobytes > 0) {
|
|
*dst++ = bitrev8(*src++);
|
|
count--;
|
|
dobytes--;
|
|
}
|
|
if (dobytes == 0) {
|
|
gigaset_rcv_skb(skb, bcs->cs, bcs);
|
|
bcs->skb = skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN);
|
|
if (!skb) {
|
|
dev_err(bcs->cs->dev,
|
|
"could not allocate skb\n");
|
|
return;
|
|
}
|
|
skb_reserve(bcs->skb, HW_HDR_LEN);
|
|
dobytes = TRANSBUFSIZE;
|
|
}
|
|
}
|
|
}
|
|
|
|
void gigaset_isoc_receive(unsigned char *src, unsigned count, struct bc_state *bcs)
|
|
{
|
|
switch (bcs->proto2) {
|
|
case ISDN_PROTO_L2_HDLC:
|
|
hdlc_unpack(src, count, bcs);
|
|
break;
|
|
default: /* assume transparent */
|
|
trans_receive(src, count, bcs);
|
|
}
|
|
}
|
|
|
|
/* == data input =========================================================== */
|
|
|
|
static void cmd_loop(unsigned char *src, int numbytes, struct inbuf_t *inbuf)
|
|
{
|
|
struct cardstate *cs = inbuf->cs;
|
|
unsigned cbytes = cs->cbytes;
|
|
|
|
while (numbytes--) {
|
|
/* copy next character, check for end of line */
|
|
switch (cs->respdata[cbytes] = *src++) {
|
|
case '\r':
|
|
case '\n':
|
|
/* end of line */
|
|
gig_dbg(DEBUG_TRANSCMD, "%s: End of Command (%d Bytes)",
|
|
__func__, cbytes);
|
|
if (cbytes >= MAX_RESP_SIZE - 1)
|
|
dev_warn(cs->dev, "response too large\n");
|
|
cs->cbytes = cbytes;
|
|
gigaset_handle_modem_response(cs);
|
|
cbytes = 0;
|
|
break;
|
|
default:
|
|
/* advance in line buffer, checking for overflow */
|
|
if (cbytes < MAX_RESP_SIZE - 1)
|
|
cbytes++;
|
|
}
|
|
}
|
|
|
|
/* save state */
|
|
cs->cbytes = cbytes;
|
|
}
|
|
|
|
|
|
/* process a block of data received through the control channel
|
|
*/
|
|
void gigaset_isoc_input(struct inbuf_t *inbuf)
|
|
{
|
|
struct cardstate *cs = inbuf->cs;
|
|
unsigned tail, head, numbytes;
|
|
unsigned char *src;
|
|
|
|
head = inbuf->head;
|
|
while (head != (tail = inbuf->tail)) {
|
|
gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", head, tail);
|
|
if (head > tail)
|
|
tail = RBUFSIZE;
|
|
src = inbuf->data + head;
|
|
numbytes = tail - head;
|
|
gig_dbg(DEBUG_INTR, "processing %u bytes", numbytes);
|
|
|
|
if (cs->mstate == MS_LOCKED) {
|
|
gigaset_dbg_buffer(DEBUG_LOCKCMD, "received response",
|
|
numbytes, src);
|
|
gigaset_if_receive(inbuf->cs, src, numbytes);
|
|
} else {
|
|
gigaset_dbg_buffer(DEBUG_CMD, "received response",
|
|
numbytes, src);
|
|
cmd_loop(src, numbytes, inbuf);
|
|
}
|
|
|
|
head += numbytes;
|
|
if (head == RBUFSIZE)
|
|
head = 0;
|
|
gig_dbg(DEBUG_INTR, "setting head to %u", head);
|
|
inbuf->head = head;
|
|
}
|
|
}
|
|
|
|
|
|
/* == data output ========================================================== */
|
|
|
|
/* gigaset_send_skb
|
|
* called by common.c to queue an skb for sending
|
|
* and start transmission if necessary
|
|
* parameters:
|
|
* B Channel control structure
|
|
* skb
|
|
* return value:
|
|
* number of bytes accepted for sending
|
|
* (skb->len if ok, 0 if out of buffer space)
|
|
* or error code (< 0, eg. -EINVAL)
|
|
*/
|
|
int gigaset_isoc_send_skb(struct bc_state *bcs, struct sk_buff *skb)
|
|
{
|
|
int len = skb->len;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&bcs->cs->lock, flags);
|
|
if (!bcs->cs->connected) {
|
|
spin_unlock_irqrestore(&bcs->cs->lock, flags);
|
|
return -ENODEV;
|
|
}
|
|
|
|
skb_queue_tail(&bcs->squeue, skb);
|
|
gig_dbg(DEBUG_ISO, "%s: skb queued, qlen=%d",
|
|
__func__, skb_queue_len(&bcs->squeue));
|
|
|
|
/* tasklet submits URB if necessary */
|
|
tasklet_schedule(&bcs->hw.bas->sent_tasklet);
|
|
spin_unlock_irqrestore(&bcs->cs->lock, flags);
|
|
|
|
return len; /* ok so far */
|
|
}
|