591 строка
15 KiB
C
591 строка
15 KiB
C
/*
|
|
* Common data handling layer for ser_gigaset and usb_gigaset
|
|
*
|
|
* Copyright (c) 2005 by Tilman Schmidt <tilman@imap.cc>,
|
|
* Hansjoerg Lipp <hjlipp@web.de>,
|
|
* Stefan Eilers.
|
|
*
|
|
* =====================================================================
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License as
|
|
* published by the Free Software Foundation; either version 2 of
|
|
* the License, or (at your option) any later version.
|
|
* =====================================================================
|
|
*/
|
|
|
|
#include "gigaset.h"
|
|
#include <linux/crc-ccitt.h>
|
|
#include <linux/bitrev.h>
|
|
|
|
//#define GIG_M10x_STUFF_VOICE_DATA
|
|
|
|
/* check if byte must be stuffed/escaped
|
|
* I'm not sure which data should be encoded.
|
|
* Therefore I will go the hard way and decode every value
|
|
* less than 0x20, the flag sequence and the control escape char.
|
|
*/
|
|
static inline int muststuff(unsigned char c)
|
|
{
|
|
if (c < PPP_TRANS) return 1;
|
|
if (c == PPP_FLAG) return 1;
|
|
if (c == PPP_ESCAPE) return 1;
|
|
/* other possible candidates: */
|
|
/* 0x91: XON with parity set */
|
|
/* 0x93: XOFF with parity set */
|
|
return 0;
|
|
}
|
|
|
|
/* == data input =========================================================== */
|
|
|
|
/* process a block of received bytes in command mode (modem response)
|
|
* Return value:
|
|
* number of processed bytes
|
|
*/
|
|
static inline int cmd_loop(unsigned char c, unsigned char *src, int numbytes,
|
|
struct inbuf_t *inbuf)
|
|
{
|
|
struct cardstate *cs = inbuf->cs;
|
|
unsigned cbytes = cs->cbytes;
|
|
int inputstate = inbuf->inputstate;
|
|
int startbytes = numbytes;
|
|
|
|
for (;;) {
|
|
cs->respdata[cbytes] = c;
|
|
if (c == 10 || c == 13) {
|
|
gig_dbg(DEBUG_TRANSCMD, "%s: End of Command (%d Bytes)",
|
|
__func__, cbytes);
|
|
cs->cbytes = cbytes;
|
|
gigaset_handle_modem_response(cs); /* can change
|
|
cs->dle */
|
|
cbytes = 0;
|
|
|
|
if (cs->dle &&
|
|
!(inputstate & INS_DLE_command)) {
|
|
inputstate &= ~INS_command;
|
|
break;
|
|
}
|
|
} else {
|
|
/* advance in line buffer, checking for overflow */
|
|
if (cbytes < MAX_RESP_SIZE - 1)
|
|
cbytes++;
|
|
else
|
|
dev_warn(cs->dev, "response too large\n");
|
|
}
|
|
|
|
if (!numbytes)
|
|
break;
|
|
c = *src++;
|
|
--numbytes;
|
|
if (c == DLE_FLAG &&
|
|
(cs->dle || inputstate & INS_DLE_command)) {
|
|
inputstate |= INS_DLE_char;
|
|
break;
|
|
}
|
|
}
|
|
|
|
cs->cbytes = cbytes;
|
|
inbuf->inputstate = inputstate;
|
|
|
|
return startbytes - numbytes;
|
|
}
|
|
|
|
/* process a block of received bytes in lock mode (tty i/f)
|
|
* Return value:
|
|
* number of processed bytes
|
|
*/
|
|
static inline int lock_loop(unsigned char *src, int numbytes,
|
|
struct inbuf_t *inbuf)
|
|
{
|
|
struct cardstate *cs = inbuf->cs;
|
|
|
|
gigaset_dbg_buffer(DEBUG_LOCKCMD, "received response",
|
|
numbytes, src);
|
|
gigaset_if_receive(cs, src, numbytes);
|
|
|
|
return numbytes;
|
|
}
|
|
|
|
/* process a block of received bytes in HDLC data mode
|
|
* Collect HDLC frames, undoing byte stuffing and watching for DLE escapes.
|
|
* When a frame is complete, check the FCS and pass valid frames to the LL.
|
|
* If DLE is encountered, return immediately to let the caller handle it.
|
|
* Return value:
|
|
* number of processed bytes
|
|
* numbytes (all bytes processed) on error --FIXME
|
|
*/
|
|
static inline int hdlc_loop(unsigned char c, unsigned char *src, int numbytes,
|
|
struct inbuf_t *inbuf)
|
|
{
|
|
struct cardstate *cs = inbuf->cs;
|
|
struct bc_state *bcs = inbuf->bcs;
|
|
int inputstate = bcs->inputstate;
|
|
__u16 fcs = bcs->fcs;
|
|
struct sk_buff *skb = bcs->skb;
|
|
unsigned char error;
|
|
struct sk_buff *compskb;
|
|
int startbytes = numbytes;
|
|
int l;
|
|
|
|
if (unlikely(inputstate & INS_byte_stuff)) {
|
|
inputstate &= ~INS_byte_stuff;
|
|
goto byte_stuff;
|
|
}
|
|
for (;;) {
|
|
if (unlikely(c == PPP_ESCAPE)) {
|
|
if (unlikely(!numbytes)) {
|
|
inputstate |= INS_byte_stuff;
|
|
break;
|
|
}
|
|
c = *src++;
|
|
--numbytes;
|
|
if (unlikely(c == DLE_FLAG &&
|
|
(cs->dle ||
|
|
inbuf->inputstate & INS_DLE_command))) {
|
|
inbuf->inputstate |= INS_DLE_char;
|
|
inputstate |= INS_byte_stuff;
|
|
break;
|
|
}
|
|
byte_stuff:
|
|
c ^= PPP_TRANS;
|
|
#ifdef CONFIG_GIGASET_DEBUG
|
|
if (unlikely(!muststuff(c)))
|
|
gig_dbg(DEBUG_HDLC, "byte stuffed: 0x%02x", c);
|
|
#endif
|
|
} else if (unlikely(c == PPP_FLAG)) {
|
|
if (unlikely(inputstate & INS_skip_frame)) {
|
|
if (!(inputstate & INS_have_data)) { /* 7E 7E */
|
|
#ifdef CONFIG_GIGASET_DEBUG
|
|
++bcs->emptycount;
|
|
#endif
|
|
} else
|
|
gig_dbg(DEBUG_HDLC,
|
|
"7e----------------------------");
|
|
|
|
/* end of frame */
|
|
error = 1;
|
|
gigaset_rcv_error(NULL, cs, bcs);
|
|
} else if (!(inputstate & INS_have_data)) { /* 7E 7E */
|
|
#ifdef CONFIG_GIGASET_DEBUG
|
|
++bcs->emptycount;
|
|
#endif
|
|
break;
|
|
} else {
|
|
gig_dbg(DEBUG_HDLC,
|
|
"7e----------------------------");
|
|
|
|
/* end of frame */
|
|
error = 0;
|
|
|
|
if (unlikely(fcs != PPP_GOODFCS)) {
|
|
dev_err(cs->dev,
|
|
"Packet checksum at %lu failed, "
|
|
"packet is corrupted (%u bytes)!\n",
|
|
bcs->rcvbytes, skb->len);
|
|
compskb = NULL;
|
|
gigaset_rcv_error(compskb, cs, bcs);
|
|
error = 1;
|
|
} else {
|
|
if (likely((l = skb->len) > 2)) {
|
|
skb->tail -= 2;
|
|
skb->len -= 2;
|
|
} else {
|
|
dev_kfree_skb(skb);
|
|
skb = NULL;
|
|
inputstate |= INS_skip_frame;
|
|
if (l == 1) {
|
|
dev_err(cs->dev,
|
|
"invalid packet size (1)!\n");
|
|
error = 1;
|
|
gigaset_rcv_error(NULL,
|
|
cs, bcs);
|
|
}
|
|
}
|
|
if (likely(!(error ||
|
|
(inputstate &
|
|
INS_skip_frame)))) {
|
|
gigaset_rcv_skb(skb, cs, bcs);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (unlikely(error))
|
|
if (skb)
|
|
dev_kfree_skb(skb);
|
|
|
|
fcs = PPP_INITFCS;
|
|
inputstate &= ~(INS_have_data | INS_skip_frame);
|
|
if (unlikely(bcs->ignore)) {
|
|
inputstate |= INS_skip_frame;
|
|
skb = NULL;
|
|
} else if (likely((skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN)) != NULL)) {
|
|
skb_reserve(skb, HW_HDR_LEN);
|
|
} else {
|
|
dev_warn(cs->dev,
|
|
"could not allocate new skb\n");
|
|
inputstate |= INS_skip_frame;
|
|
}
|
|
|
|
break;
|
|
#ifdef CONFIG_GIGASET_DEBUG
|
|
} else if (unlikely(muststuff(c))) {
|
|
/* Should not happen. Possible after ZDLE=1<CR><LF>. */
|
|
gig_dbg(DEBUG_HDLC, "not byte stuffed: 0x%02x", c);
|
|
#endif
|
|
}
|
|
|
|
/* add character */
|
|
|
|
#ifdef CONFIG_GIGASET_DEBUG
|
|
if (unlikely(!(inputstate & INS_have_data))) {
|
|
gig_dbg(DEBUG_HDLC, "7e (%d x) ================",
|
|
bcs->emptycount);
|
|
bcs->emptycount = 0;
|
|
}
|
|
#endif
|
|
|
|
inputstate |= INS_have_data;
|
|
|
|
if (likely(!(inputstate & INS_skip_frame))) {
|
|
if (unlikely(skb->len == SBUFSIZE)) {
|
|
dev_warn(cs->dev, "received packet too long\n");
|
|
dev_kfree_skb_any(skb);
|
|
skb = NULL;
|
|
inputstate |= INS_skip_frame;
|
|
break;
|
|
}
|
|
*__skb_put(skb, 1) = c;
|
|
fcs = crc_ccitt_byte(fcs, c);
|
|
}
|
|
|
|
if (unlikely(!numbytes))
|
|
break;
|
|
c = *src++;
|
|
--numbytes;
|
|
if (unlikely(c == DLE_FLAG &&
|
|
(cs->dle ||
|
|
inbuf->inputstate & INS_DLE_command))) {
|
|
inbuf->inputstate |= INS_DLE_char;
|
|
break;
|
|
}
|
|
}
|
|
bcs->inputstate = inputstate;
|
|
bcs->fcs = fcs;
|
|
bcs->skb = skb;
|
|
return startbytes - numbytes;
|
|
}
|
|
|
|
/* process a block of received bytes in transparent data mode
|
|
* Invert bytes, undoing byte stuffing and watching for DLE escapes.
|
|
* If DLE is encountered, return immediately to let the caller handle it.
|
|
* Return value:
|
|
* number of processed bytes
|
|
* numbytes (all bytes processed) on error --FIXME
|
|
*/
|
|
static inline int iraw_loop(unsigned char c, unsigned char *src, int numbytes,
|
|
struct inbuf_t *inbuf)
|
|
{
|
|
struct cardstate *cs = inbuf->cs;
|
|
struct bc_state *bcs = inbuf->bcs;
|
|
int inputstate = bcs->inputstate;
|
|
struct sk_buff *skb = bcs->skb;
|
|
int startbytes = numbytes;
|
|
|
|
for (;;) {
|
|
/* add character */
|
|
inputstate |= INS_have_data;
|
|
|
|
if (likely(!(inputstate & INS_skip_frame))) {
|
|
if (unlikely(skb->len == SBUFSIZE)) {
|
|
//FIXME just pass skb up and allocate a new one
|
|
dev_warn(cs->dev, "received packet too long\n");
|
|
dev_kfree_skb_any(skb);
|
|
skb = NULL;
|
|
inputstate |= INS_skip_frame;
|
|
break;
|
|
}
|
|
*__skb_put(skb, 1) = bitrev8(c);
|
|
}
|
|
|
|
if (unlikely(!numbytes))
|
|
break;
|
|
c = *src++;
|
|
--numbytes;
|
|
if (unlikely(c == DLE_FLAG &&
|
|
(cs->dle ||
|
|
inbuf->inputstate & INS_DLE_command))) {
|
|
inbuf->inputstate |= INS_DLE_char;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* pass data up */
|
|
if (likely(inputstate & INS_have_data)) {
|
|
if (likely(!(inputstate & INS_skip_frame))) {
|
|
gigaset_rcv_skb(skb, cs, bcs);
|
|
}
|
|
inputstate &= ~(INS_have_data | INS_skip_frame);
|
|
if (unlikely(bcs->ignore)) {
|
|
inputstate |= INS_skip_frame;
|
|
skb = NULL;
|
|
} else if (likely((skb = dev_alloc_skb(SBUFSIZE + HW_HDR_LEN))
|
|
!= NULL)) {
|
|
skb_reserve(skb, HW_HDR_LEN);
|
|
} else {
|
|
dev_warn(cs->dev, "could not allocate new skb\n");
|
|
inputstate |= INS_skip_frame;
|
|
}
|
|
}
|
|
|
|
bcs->inputstate = inputstate;
|
|
bcs->skb = skb;
|
|
return startbytes - numbytes;
|
|
}
|
|
|
|
/* process a block of data received from the device
|
|
*/
|
|
void gigaset_m10x_input(struct inbuf_t *inbuf)
|
|
{
|
|
struct cardstate *cs;
|
|
unsigned tail, head, numbytes;
|
|
unsigned char *src, c;
|
|
int procbytes;
|
|
|
|
head = inbuf->head;
|
|
tail = inbuf->tail;
|
|
gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", head, tail);
|
|
|
|
if (head != tail) {
|
|
cs = inbuf->cs;
|
|
src = inbuf->data + head;
|
|
numbytes = (head > tail ? RBUFSIZE : tail) - head;
|
|
gig_dbg(DEBUG_INTR, "processing %u bytes", numbytes);
|
|
|
|
while (numbytes) {
|
|
if (cs->mstate == MS_LOCKED) {
|
|
procbytes = lock_loop(src, numbytes, inbuf);
|
|
src += procbytes;
|
|
numbytes -= procbytes;
|
|
} else {
|
|
c = *src++;
|
|
--numbytes;
|
|
if (c == DLE_FLAG && (cs->dle ||
|
|
inbuf->inputstate & INS_DLE_command)) {
|
|
if (!(inbuf->inputstate & INS_DLE_char)) {
|
|
inbuf->inputstate |= INS_DLE_char;
|
|
goto nextbyte;
|
|
}
|
|
/* <DLE> <DLE> => <DLE> in data stream */
|
|
inbuf->inputstate &= ~INS_DLE_char;
|
|
}
|
|
|
|
if (!(inbuf->inputstate & INS_DLE_char)) {
|
|
|
|
/* FIXME use function pointers? */
|
|
if (inbuf->inputstate & INS_command)
|
|
procbytes = cmd_loop(c, src, numbytes, inbuf);
|
|
else if (inbuf->bcs->proto2 == ISDN_PROTO_L2_HDLC)
|
|
procbytes = hdlc_loop(c, src, numbytes, inbuf);
|
|
else
|
|
procbytes = iraw_loop(c, src, numbytes, inbuf);
|
|
|
|
src += procbytes;
|
|
numbytes -= procbytes;
|
|
} else { /* DLE char */
|
|
inbuf->inputstate &= ~INS_DLE_char;
|
|
switch (c) {
|
|
case 'X': /*begin of command*/
|
|
#ifdef CONFIG_GIGASET_DEBUG
|
|
if (inbuf->inputstate & INS_command)
|
|
dev_err(cs->dev,
|
|
"received <DLE> 'X' in command mode\n");
|
|
#endif
|
|
inbuf->inputstate |=
|
|
INS_command | INS_DLE_command;
|
|
break;
|
|
case '.': /*end of command*/
|
|
#ifdef CONFIG_GIGASET_DEBUG
|
|
if (!(inbuf->inputstate & INS_command))
|
|
dev_err(cs->dev,
|
|
"received <DLE> '.' in hdlc mode\n");
|
|
#endif
|
|
inbuf->inputstate &= cs->dle ?
|
|
~(INS_DLE_command|INS_command)
|
|
: ~INS_DLE_command;
|
|
break;
|
|
//case DLE_FLAG: /*DLE_FLAG in data stream*/ /* schon oben behandelt! */
|
|
default:
|
|
dev_err(cs->dev,
|
|
"received 0x10 0x%02x!\n",
|
|
(int) c);
|
|
/* FIXME: reset driver?? */
|
|
}
|
|
}
|
|
}
|
|
nextbyte:
|
|
if (!numbytes) {
|
|
/* end of buffer, check for wrap */
|
|
if (head > tail) {
|
|
head = 0;
|
|
src = inbuf->data;
|
|
numbytes = tail;
|
|
} else {
|
|
head = tail;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
gig_dbg(DEBUG_INTR, "setting head to %u", head);
|
|
inbuf->head = head;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(gigaset_m10x_input);
|
|
|
|
|
|
/* == data output ========================================================== */
|
|
|
|
/* Encoding of a PPP packet into an octet stuffed HDLC frame
|
|
* with FCS, opening and closing flags.
|
|
* parameters:
|
|
* skb skb containing original packet (freed upon return)
|
|
* head number of headroom bytes to allocate in result skb
|
|
* tail number of tailroom bytes to allocate in result skb
|
|
* Return value:
|
|
* pointer to newly allocated skb containing the result frame
|
|
*/
|
|
static struct sk_buff *HDLC_Encode(struct sk_buff *skb, int head, int tail)
|
|
{
|
|
struct sk_buff *hdlc_skb;
|
|
__u16 fcs;
|
|
unsigned char c;
|
|
unsigned char *cp;
|
|
int len;
|
|
unsigned int stuf_cnt;
|
|
|
|
stuf_cnt = 0;
|
|
fcs = PPP_INITFCS;
|
|
cp = skb->data;
|
|
len = skb->len;
|
|
while (len--) {
|
|
if (muststuff(*cp))
|
|
stuf_cnt++;
|
|
fcs = crc_ccitt_byte(fcs, *cp++);
|
|
}
|
|
fcs ^= 0xffff; /* complement */
|
|
|
|
/* size of new buffer: original size + number of stuffing bytes
|
|
* + 2 bytes FCS + 2 stuffing bytes for FCS (if needed) + 2 flag bytes
|
|
*/
|
|
hdlc_skb = dev_alloc_skb(skb->len + stuf_cnt + 6 + tail + head);
|
|
if (!hdlc_skb) {
|
|
dev_kfree_skb(skb);
|
|
return NULL;
|
|
}
|
|
skb_reserve(hdlc_skb, head);
|
|
|
|
/* Copy acknowledge request into new skb */
|
|
memcpy(hdlc_skb->head, skb->head, 2);
|
|
|
|
/* Add flag sequence in front of everything.. */
|
|
*(skb_put(hdlc_skb, 1)) = PPP_FLAG;
|
|
|
|
/* Perform byte stuffing while copying data. */
|
|
while (skb->len--) {
|
|
if (muststuff(*skb->data)) {
|
|
*(skb_put(hdlc_skb, 1)) = PPP_ESCAPE;
|
|
*(skb_put(hdlc_skb, 1)) = (*skb->data++) ^ PPP_TRANS;
|
|
} else
|
|
*(skb_put(hdlc_skb, 1)) = *skb->data++;
|
|
}
|
|
|
|
/* Finally add FCS (byte stuffed) and flag sequence */
|
|
c = (fcs & 0x00ff); /* least significant byte first */
|
|
if (muststuff(c)) {
|
|
*(skb_put(hdlc_skb, 1)) = PPP_ESCAPE;
|
|
c ^= PPP_TRANS;
|
|
}
|
|
*(skb_put(hdlc_skb, 1)) = c;
|
|
|
|
c = ((fcs >> 8) & 0x00ff);
|
|
if (muststuff(c)) {
|
|
*(skb_put(hdlc_skb, 1)) = PPP_ESCAPE;
|
|
c ^= PPP_TRANS;
|
|
}
|
|
*(skb_put(hdlc_skb, 1)) = c;
|
|
|
|
*(skb_put(hdlc_skb, 1)) = PPP_FLAG;
|
|
|
|
dev_kfree_skb(skb);
|
|
return hdlc_skb;
|
|
}
|
|
|
|
/* Encoding of a raw packet into an octet stuffed bit inverted frame
|
|
* parameters:
|
|
* skb skb containing original packet (freed upon return)
|
|
* head number of headroom bytes to allocate in result skb
|
|
* tail number of tailroom bytes to allocate in result skb
|
|
* Return value:
|
|
* pointer to newly allocated skb containing the result frame
|
|
*/
|
|
static struct sk_buff *iraw_encode(struct sk_buff *skb, int head, int tail)
|
|
{
|
|
struct sk_buff *iraw_skb;
|
|
unsigned char c;
|
|
unsigned char *cp;
|
|
int len;
|
|
|
|
/* worst case: every byte must be stuffed */
|
|
iraw_skb = dev_alloc_skb(2*skb->len + tail + head);
|
|
if (!iraw_skb) {
|
|
dev_kfree_skb(skb);
|
|
return NULL;
|
|
}
|
|
skb_reserve(iraw_skb, head);
|
|
|
|
cp = skb->data;
|
|
len = skb->len;
|
|
while (len--) {
|
|
c = bitrev8(*cp++);
|
|
if (c == DLE_FLAG)
|
|
*(skb_put(iraw_skb, 1)) = c;
|
|
*(skb_put(iraw_skb, 1)) = c;
|
|
}
|
|
dev_kfree_skb(skb);
|
|
return iraw_skb;
|
|
}
|
|
|
|
/* 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_m10x_send_skb(struct bc_state *bcs, struct sk_buff *skb)
|
|
{
|
|
unsigned len = skb->len;
|
|
unsigned long flags;
|
|
|
|
if (bcs->proto2 == ISDN_PROTO_L2_HDLC)
|
|
skb = HDLC_Encode(skb, HW_HDR_LEN, 0);
|
|
else
|
|
skb = iraw_encode(skb, HW_HDR_LEN, 0);
|
|
if (!skb) {
|
|
err("unable to allocate memory for encoding!\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
skb_queue_tail(&bcs->squeue, skb);
|
|
spin_lock_irqsave(&bcs->cs->lock, flags);
|
|
if (bcs->cs->connected)
|
|
tasklet_schedule(&bcs->cs->write_tasklet);
|
|
spin_unlock_irqrestore(&bcs->cs->lock, flags);
|
|
|
|
return len; /* ok so far */
|
|
}
|
|
EXPORT_SYMBOL_GPL(gigaset_m10x_send_skb);
|