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authorLinus Torvalds <torvalds@linux-foundation.org>2019-07-11 19:55:49 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2019-07-11 19:55:49 +0200
commit237f83dfbe668443b5e31c3c7576125871cca674 (patch)
tree11848a8d0aa414a1d3ce2024e181071b1d9dea08 /drivers/isdn/hardware/mISDN/isdnhdlc.c
parentMerge tag 'clone3-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brau... (diff)
parentnet/mlx5e: Return in default case statement in tx_post_resync_params (diff)
downloadlinux-237f83dfbe668443b5e31c3c7576125871cca674.tar.xz
linux-237f83dfbe668443b5e31c3c7576125871cca674.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: "Some highlights from this development cycle: 1) Big refactoring of ipv6 route and neigh handling to support nexthop objects configurable as units from userspace. From David Ahern. 2) Convert explored_states in BPF verifier into a hash table, significantly decreased state held for programs with bpf2bpf calls, from Alexei Starovoitov. 3) Implement bpf_send_signal() helper, from Yonghong Song. 4) Various classifier enhancements to mvpp2 driver, from Maxime Chevallier. 5) Add aRFS support to hns3 driver, from Jian Shen. 6) Fix use after free in inet frags by allocating fqdirs dynamically and reworking how rhashtable dismantle occurs, from Eric Dumazet. 7) Add act_ctinfo packet classifier action, from Kevin Darbyshire-Bryant. 8) Add TFO key backup infrastructure, from Jason Baron. 9) Remove several old and unused ISDN drivers, from Arnd Bergmann. 10) Add devlink notifications for flash update status to mlxsw driver, from Jiri Pirko. 11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski. 12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes. 13) Various enhancements to ipv6 flow label handling, from Eric Dumazet and Willem de Bruijn. 14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van der Merwe, and others. 15) Various improvements to axienet driver including converting it to phylink, from Robert Hancock. 16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean. 17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana Radulescu. 18) Add devlink health reporting to mlx5, from Moshe Shemesh. 19) Convert stmmac over to phylink, from Jose Abreu. 20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from Shalom Toledo. 21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera. 22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel. 23) Track spill/fill of constants in BPF verifier, from Alexei Starovoitov. 24) Support bounded loops in BPF, from Alexei Starovoitov. 25) Various page_pool API fixes and improvements, from Jesper Dangaard Brouer. 26) Just like ipv4, support ref-countless ipv6 route handling. From Wei Wang. 27) Support VLAN offloading in aquantia driver, from Igor Russkikh. 28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy. 29) Add flower GRE encap/decap support to nfp driver, from Pieter Jansen van Vuuren. 30) Protect against stack overflow when using act_mirred, from John Hurley. 31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen. 32) Use page_pool API in netsec driver, Ilias Apalodimas. 33) Add Google gve network driver, from Catherine Sullivan. 34) More indirect call avoidance, from Paolo Abeni. 35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan. 36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek. 37) Add MPLS manipulation actions to TC, from John Hurley. 38) Add sending a packet to connection tracking from TC actions, and then allow flower classifier matching on conntrack state. From Paul Blakey. 39) Netfilter hw offload support, from Pablo Neira Ayuso" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits) net/mlx5e: Return in default case statement in tx_post_resync_params mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync(). net: dsa: add support for BRIDGE_MROUTER attribute pkt_sched: Include const.h net: netsec: remove static declaration for netsec_set_tx_de() net: netsec: remove superfluous if statement netfilter: nf_tables: add hardware offload support net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload net: flow_offload: add flow_block_cb_is_busy() and use it net: sched: remove tcf block API drivers: net: use flow block API net: sched: use flow block API net: flow_offload: add flow_block_cb_{priv, incref, decref}() net: flow_offload: add list handling functions net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free() net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_* net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND net: flow_offload: add flow_block_cb_setup_simple() net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC ...
Diffstat (limited to 'drivers/isdn/hardware/mISDN/isdnhdlc.c')
-rw-r--r--drivers/isdn/hardware/mISDN/isdnhdlc.c617
1 files changed, 617 insertions, 0 deletions
diff --git a/drivers/isdn/hardware/mISDN/isdnhdlc.c b/drivers/isdn/hardware/mISDN/isdnhdlc.c
new file mode 100644
index 000000000000..9fea16ed3dd8
--- /dev/null
+++ b/drivers/isdn/hardware/mISDN/isdnhdlc.c
@@ -0,0 +1,617 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * isdnhdlc.c -- General purpose ISDN HDLC decoder.
+ *
+ * Copyright (C)
+ * 2009 Karsten Keil <keil@b1-systems.de>
+ * 2002 Wolfgang Mües <wolfgang@iksw-muees.de>
+ * 2001 Frode Isaksen <fisaksen@bewan.com>
+ * 2001 Kai Germaschewski <kai.germaschewski@gmx.de>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/crc-ccitt.h>
+#include <linux/bitrev.h>
+#include "isdnhdlc.h"
+
+/*-------------------------------------------------------------------*/
+
+MODULE_AUTHOR("Wolfgang Mües <wolfgang@iksw-muees.de>, "
+ "Frode Isaksen <fisaksen@bewan.com>, "
+ "Kai Germaschewski <kai.germaschewski@gmx.de>");
+MODULE_DESCRIPTION("General purpose ISDN HDLC decoder");
+MODULE_LICENSE("GPL");
+
+/*-------------------------------------------------------------------*/
+
+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, HDLC_SENDFLAG_ONE
+};
+
+void isdnhdlc_rcv_init(struct isdnhdlc_vars *hdlc, u32 features)
+{
+ memset(hdlc, 0, sizeof(struct isdnhdlc_vars));
+ hdlc->state = HDLC_GET_DATA;
+ if (features & HDLC_56KBIT)
+ hdlc->do_adapt56 = 1;
+ if (features & HDLC_BITREVERSE)
+ hdlc->do_bitreverse = 1;
+}
+EXPORT_SYMBOL(isdnhdlc_out_init);
+
+void isdnhdlc_out_init(struct isdnhdlc_vars *hdlc, u32 features)
+{
+ memset(hdlc, 0, sizeof(struct isdnhdlc_vars));
+ if (features & HDLC_DCHANNEL) {
+ 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;
+ if (features & HDLC_56KBIT) {
+ hdlc->do_adapt56 = 1;
+ hdlc->state = HDLC_SENDFLAG_B0;
+ } else
+ hdlc->data_bits = 8;
+ if (features & HDLC_BITREVERSE)
+ hdlc->do_bitreverse = 1;
+}
+EXPORT_SYMBOL(isdnhdlc_rcv_init);
+
+static int
+check_frame(struct isdnhdlc_vars *hdlc)
+{
+ int status;
+
+ if (hdlc->dstpos < 2) /* too small - framing error */
+ 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;
+ }
+ return status;
+}
+
+/*
+ isdnhdlc_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 isdnhdlc_decode(struct isdnhdlc_vars *hdlc, const u8 *src, int slen,
+ int *count, u8 *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
+ };
+
+#define handle_fast_flag(h) \
+ do { \
+ if (h->cbin == fast_flag[h->bit_shift]) { \
+ h->ffvalue = fast_flag_value[h->bit_shift]; \
+ h->state = HDLC_FAST_FLAG; \
+ h->ffbit_shift = h->bit_shift; \
+ h->bit_shift = 1; \
+ } else { \
+ h->state = HDLC_GET_DATA; \
+ h->data_received = 0; \
+ } \
+ } while (0)
+
+#define handle_abort(h) \
+ do { \
+ h->shift_reg = fast_abort[h->ffbit_shift - 1]; \
+ h->hdlc_bits1 = h->ffbit_shift - 2; \
+ if (h->hdlc_bits1 < 0) \
+ h->hdlc_bits1 = 0; \
+ h->data_bits = h->ffbit_shift - 1; \
+ h->state = HDLC_GET_DATA; \
+ h->data_received = 0; \
+ } while (0)
+
+ *count = slen;
+
+ while (slen > 0) {
+ if (hdlc->bit_shift == 0) {
+ /* the code is for bitreverse streams */
+ if (hdlc->do_bitreverse == 0)
+ hdlc->cbin = bitrev8(*src++);
+ else
+ 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) &&
+ (++hdlc->hdlc_bits1 >= 8) &&
+ (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)
+ status = check_frame(hdlc);
+ hdlc->crc = 0xffff;
+ hdlc->shift_reg = 0;
+ hdlc->data_bits = 0;
+ if (!hdlc->do_adapt56)
+ handle_fast_flag(hdlc);
+ 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 (hdlc->dstpos < 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
+ handle_abort(hdlc);
+ }
+ break;
+ default:
+ break;
+ }
+ }
+ *count -= slen;
+ return 0;
+}
+EXPORT_SYMBOL(isdnhdlc_decode);
+/*
+ isdnhdlc_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 isdnhdlc_encode(struct isdnhdlc_vars *hdlc, const u8 *src, u16 slen,
+ int *count, u8 *dst, int dsize)
+{
+ static const unsigned char xfast_flag_value[] = {
+ 0x7e, 0x3f, 0x9f, 0xcf, 0xe7, 0xf3, 0xf9, 0xfc, 0x7e
+ };
+
+ int len = 0;
+
+ *count = slen;
+
+ /* special handling for one byte frames */
+ if ((slen == 1) && (hdlc->state == HDLC_SEND_FAST_FLAG))
+ hdlc->state = HDLC_SENDFLAG_ONE;
+ while (dsize > 0) {
+ if (hdlc->bit_shift == 0) {
+ if (slen && !hdlc->do_closing) {
+ hdlc->shift_reg = *src++;
+ slen--;
+ if (slen == 0)
+ /* closing sequence, CRC + flag(s) */
+ hdlc->do_closing = 1;
+ 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) {
+ /* the code is for bitreverse streams */
+ if (hdlc->do_bitreverse == 0)
+ *dst++ = bitrev8(hdlc->ffvalue);
+ else
+ *dst++ = hdlc->ffvalue;
+ len++;
+ dsize--;
+ break;
+ }
+ /* fall through */
+ case HDLC_SENDFLAG_ONE:
+ 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 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 {
+ /* the code is for bitreverse streams */
+ if (hdlc->do_bitreverse == 0)
+ *dst++ = bitrev8(hdlc->cbin);
+ else
+ *dst++ = hdlc->cbin;
+ hdlc->bit_shift = 0;
+ 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) {
+ /* the code is for bitreverse streams */
+ if (hdlc->do_bitreverse == 0)
+ *dst++ = bitrev8(hdlc->cbin);
+ else
+ *dst++ = hdlc->cbin;
+ hdlc->data_bits = 0;
+ len++;
+ dsize--;
+ }
+ }
+ *count -= slen;
+
+ return len;
+}
+EXPORT_SYMBOL(isdnhdlc_encode);