diff options
Diffstat (limited to 'drivers/isdn/gigaset/asyncdata.c')
-rw-r--r-- | drivers/isdn/gigaset/asyncdata.c | 609 |
1 files changed, 0 insertions, 609 deletions
diff --git a/drivers/isdn/gigaset/asyncdata.c b/drivers/isdn/gigaset/asyncdata.c deleted file mode 100644 index c0cbee06bc21..000000000000 --- a/drivers/isdn/gigaset/asyncdata.c +++ /dev/null @@ -1,609 +0,0 @@ -/* - * 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> -#include <linux/export.h> - -/* check if byte must be stuffed/escaped - * I'm not sure which data should be encoded. - * Therefore I will go the hard way and encode 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 - * (mstate != MS_LOCKED && (inputstate & INS_command)) - * Append received bytes to the command response buffer and forward them - * line by line to the response handler. Exit whenever a mode/state change - * might have occurred. - * Note: Received lines may be terminated by CR, LF, or CR LF, which will be - * removed before passing the line to the response handler. - * Return value: - * number of processed bytes - */ -static unsigned cmd_loop(unsigned numbytes, struct inbuf_t *inbuf) -{ - unsigned char *src = inbuf->data + inbuf->head; - struct cardstate *cs = inbuf->cs; - unsigned cbytes = cs->cbytes; - unsigned procbytes = 0; - unsigned char c; - - while (procbytes < numbytes) { - c = *src++; - procbytes++; - - switch (c) { - case '\n': - if (cbytes == 0 && cs->respdata[0] == '\r') { - /* collapse LF with preceding CR */ - cs->respdata[0] = 0; - break; - } - /* fall through */ - case '\r': - /* end of message line, pass to response handler */ - if (cbytes >= MAX_RESP_SIZE) { - dev_warn(cs->dev, "response too large (%d)\n", - cbytes); - cbytes = MAX_RESP_SIZE; - } - cs->cbytes = cbytes; - gigaset_dbg_buffer(DEBUG_TRANSCMD, "received response", - cbytes, cs->respdata); - gigaset_handle_modem_response(cs); - cbytes = 0; - - /* store EOL byte for CRLF collapsing */ - cs->respdata[0] = c; - - /* cs->dle may have changed */ - if (cs->dle && !(inbuf->inputstate & INS_DLE_command)) - inbuf->inputstate &= ~INS_command; - - /* return for reevaluating state */ - goto exit; - - case DLE_FLAG: - if (inbuf->inputstate & INS_DLE_char) { - /* quoted DLE: clear quote flag */ - inbuf->inputstate &= ~INS_DLE_char; - } else if (cs->dle || - (inbuf->inputstate & INS_DLE_command)) { - /* DLE escape, pass up for handling */ - inbuf->inputstate |= INS_DLE_char; - goto exit; - } - /* quoted or not in DLE mode: treat as regular data */ - /* fall through */ - default: - /* append to line buffer if possible */ - if (cbytes < MAX_RESP_SIZE) - cs->respdata[cbytes] = c; - cbytes++; - } - } -exit: - cs->cbytes = cbytes; - return procbytes; -} - -/* process a block of received bytes in lock mode - * All received bytes are passed unmodified to the tty i/f. - * Return value: - * number of processed bytes - */ -static unsigned lock_loop(unsigned numbytes, struct inbuf_t *inbuf) -{ - unsigned char *src = inbuf->data + inbuf->head; - - gigaset_dbg_buffer(DEBUG_LOCKCMD, "received response", numbytes, src); - gigaset_if_receive(inbuf->cs, src, numbytes); - return numbytes; -} - -/* process a block of received bytes in HDLC data mode - * (mstate != MS_LOCKED && !(inputstate & INS_command) && proto2 == L2_HDLC) - * 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 - */ -static unsigned hdlc_loop(unsigned numbytes, struct inbuf_t *inbuf) -{ - struct cardstate *cs = inbuf->cs; - struct bc_state *bcs = cs->bcs; - int inputstate = bcs->inputstate; - __u16 fcs = bcs->rx_fcs; - struct sk_buff *skb = bcs->rx_skb; - unsigned char *src = inbuf->data + inbuf->head; - unsigned procbytes = 0; - unsigned char c; - - if (inputstate & INS_byte_stuff) { - if (!numbytes) - return 0; - inputstate &= ~INS_byte_stuff; - goto byte_stuff; - } - - while (procbytes < numbytes) { - c = *src++; - procbytes++; - if (c == DLE_FLAG) { - if (inputstate & INS_DLE_char) { - /* quoted DLE: clear quote flag */ - inputstate &= ~INS_DLE_char; - } else if (cs->dle || (inputstate & INS_DLE_command)) { - /* DLE escape, pass up for handling */ - inputstate |= INS_DLE_char; - break; - } - } - - if (c == PPP_ESCAPE) { - /* byte stuffing indicator: pull in next byte */ - if (procbytes >= numbytes) { - /* end of buffer, save for later processing */ - inputstate |= INS_byte_stuff; - break; - } -byte_stuff: - c = *src++; - procbytes++; - if (c == DLE_FLAG) { - if (inputstate & INS_DLE_char) { - /* quoted DLE: clear quote flag */ - inputstate &= ~INS_DLE_char; - } else if (cs->dle || - (inputstate & INS_DLE_command)) { - /* DLE escape, pass up for handling */ - inputstate |= - INS_DLE_char | INS_byte_stuff; - break; - } - } - c ^= PPP_TRANS; -#ifdef CONFIG_GIGASET_DEBUG - if (!muststuff(c)) - gig_dbg(DEBUG_HDLC, "byte stuffed: 0x%02x", c); -#endif - } else if (c == PPP_FLAG) { - /* end of frame: process content if any */ - if (inputstate & INS_have_data) { - gig_dbg(DEBUG_HDLC, - "7e----------------------------"); - - /* check and pass received frame */ - if (!skb) { - /* skipped frame */ - gigaset_isdn_rcv_err(bcs); - } else if (skb->len < 2) { - /* frame too short for FCS */ - dev_warn(cs->dev, - "short frame (%d)\n", - skb->len); - gigaset_isdn_rcv_err(bcs); - dev_kfree_skb_any(skb); - } else if (fcs != PPP_GOODFCS) { - /* frame check error */ - dev_err(cs->dev, - "Checksum failed, %u bytes corrupted!\n", - skb->len); - gigaset_isdn_rcv_err(bcs); - dev_kfree_skb_any(skb); - } else { - /* good frame */ - __skb_trim(skb, skb->len - 2); - gigaset_skb_rcvd(bcs, skb); - } - - /* prepare reception of next frame */ - inputstate &= ~INS_have_data; - skb = gigaset_new_rx_skb(bcs); - } else { - /* empty frame (7E 7E) */ -#ifdef CONFIG_GIGASET_DEBUG - ++bcs->emptycount; -#endif - if (!skb) { - /* skipped (?) */ - gigaset_isdn_rcv_err(bcs); - skb = gigaset_new_rx_skb(bcs); - } - } - - fcs = PPP_INITFCS; - continue; -#ifdef CONFIG_GIGASET_DEBUG - } else if (muststuff(c)) { - /* Should not happen. Possible after ZDLE=1<CR><LF>. */ - gig_dbg(DEBUG_HDLC, "not byte stuffed: 0x%02x", c); -#endif - } - - /* regular data byte, append to skb */ -#ifdef CONFIG_GIGASET_DEBUG - if (!(inputstate & INS_have_data)) { - gig_dbg(DEBUG_HDLC, "7e (%d x) ================", - bcs->emptycount); - bcs->emptycount = 0; - } -#endif - inputstate |= INS_have_data; - if (skb) { - if (skb->len >= bcs->rx_bufsize) { - dev_warn(cs->dev, "received packet too long\n"); - dev_kfree_skb_any(skb); - /* skip remainder of packet */ - bcs->rx_skb = skb = NULL; - } else { - __skb_put_u8(skb, c); - fcs = crc_ccitt_byte(fcs, c); - } - } - } - - bcs->inputstate = inputstate; - bcs->rx_fcs = fcs; - return procbytes; -} - -/* process a block of received bytes in transparent data mode - * (mstate != MS_LOCKED && !(inputstate & INS_command) && proto2 != L2_HDLC) - * 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 - */ -static unsigned iraw_loop(unsigned numbytes, struct inbuf_t *inbuf) -{ - struct cardstate *cs = inbuf->cs; - struct bc_state *bcs = cs->bcs; - int inputstate = bcs->inputstate; - struct sk_buff *skb = bcs->rx_skb; - unsigned char *src = inbuf->data + inbuf->head; - unsigned procbytes = 0; - unsigned char c; - - if (!skb) { - /* skip this block */ - gigaset_new_rx_skb(bcs); - return numbytes; - } - - while (procbytes < numbytes && skb->len < bcs->rx_bufsize) { - c = *src++; - procbytes++; - - if (c == DLE_FLAG) { - if (inputstate & INS_DLE_char) { - /* quoted DLE: clear quote flag */ - inputstate &= ~INS_DLE_char; - } else if (cs->dle || (inputstate & INS_DLE_command)) { - /* DLE escape, pass up for handling */ - inputstate |= INS_DLE_char; - break; - } - } - - /* regular data byte: append to current skb */ - inputstate |= INS_have_data; - __skb_put_u8(skb, bitrev8(c)); - } - - /* pass data up */ - if (inputstate & INS_have_data) { - gigaset_skb_rcvd(bcs, skb); - inputstate &= ~INS_have_data; - gigaset_new_rx_skb(bcs); - } - - bcs->inputstate = inputstate; - return procbytes; -} - -/* process DLE escapes - * Called whenever a DLE sequence might be encountered in the input stream. - * Either processes the entire DLE sequence or, if that isn't possible, - * notes the fact that an initial DLE has been received in the INS_DLE_char - * inputstate flag and resumes processing of the sequence on the next call. - */ -static void handle_dle(struct inbuf_t *inbuf) -{ - struct cardstate *cs = inbuf->cs; - - if (cs->mstate == MS_LOCKED) - return; /* no DLE processing in lock mode */ - - if (!(inbuf->inputstate & INS_DLE_char)) { - /* no DLE pending */ - if (inbuf->data[inbuf->head] == DLE_FLAG && - (cs->dle || inbuf->inputstate & INS_DLE_command)) { - /* start of DLE sequence */ - inbuf->head++; - if (inbuf->head == inbuf->tail || - inbuf->head == RBUFSIZE) { - /* end of buffer, save for later processing */ - inbuf->inputstate |= INS_DLE_char; - return; - } - } else { - /* regular data byte */ - return; - } - } - - /* consume pending DLE */ - inbuf->inputstate &= ~INS_DLE_char; - - switch (inbuf->data[inbuf->head]) { - case 'X': /* begin of event message */ - if (inbuf->inputstate & INS_command) - dev_notice(cs->dev, - "received <DLE>X in command mode\n"); - inbuf->inputstate |= INS_command | INS_DLE_command; - inbuf->head++; /* byte consumed */ - break; - case '.': /* end of event message */ - if (!(inbuf->inputstate & INS_DLE_command)) - dev_notice(cs->dev, - "received <DLE>. without <DLE>X\n"); - inbuf->inputstate &= ~INS_DLE_command; - /* return to data mode if in DLE mode */ - if (cs->dle) - inbuf->inputstate &= ~INS_command; - inbuf->head++; /* byte consumed */ - break; - case DLE_FLAG: /* DLE in data stream */ - /* mark as quoted */ - inbuf->inputstate |= INS_DLE_char; - if (!(cs->dle || inbuf->inputstate & INS_DLE_command)) - dev_notice(cs->dev, - "received <DLE><DLE> not in DLE mode\n"); - break; /* quoted byte left in buffer */ - default: - dev_notice(cs->dev, "received <DLE><%02x>\n", - inbuf->data[inbuf->head]); - /* quoted byte left in buffer */ - } -} - -/** - * gigaset_m10x_input() - process a block of data received from the device - * @inbuf: received data and device descriptor structure. - * - * Called by hardware module {ser,usb}_gigaset with a block of received - * bytes. Separates the bytes received over the serial data channel into - * user data and command replies (locked/unlocked) according to the - * current state of the interface. - */ -void gigaset_m10x_input(struct inbuf_t *inbuf) -{ - struct cardstate *cs = inbuf->cs; - unsigned numbytes, procbytes; - - gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", inbuf->head, inbuf->tail); - - while (inbuf->head != inbuf->tail) { - /* check for DLE escape */ - handle_dle(inbuf); - - /* process a contiguous block of bytes */ - numbytes = (inbuf->head > inbuf->tail ? - RBUFSIZE : inbuf->tail) - inbuf->head; - gig_dbg(DEBUG_INTR, "processing %u bytes", numbytes); - /* - * numbytes may be 0 if handle_dle() ate the last byte. - * This does no harm, *_loop() will just return 0 immediately. - */ - - if (cs->mstate == MS_LOCKED) - procbytes = lock_loop(numbytes, inbuf); - else if (inbuf->inputstate & INS_command) - procbytes = cmd_loop(numbytes, inbuf); - else if (cs->bcs->proto2 == L2_HDLC) - procbytes = hdlc_loop(numbytes, inbuf); - else - procbytes = iraw_loop(numbytes, inbuf); - inbuf->head += procbytes; - - /* check for buffer wraparound */ - if (inbuf->head >= RBUFSIZE) - inbuf->head = 0; - - gig_dbg(DEBUG_INTR, "head set to %u", inbuf->head); - } -} -EXPORT_SYMBOL_GPL(gigaset_m10x_input); - - -/* == data output ========================================================== */ - -/* - * Encode a data packet into an octet stuffed HDLC frame with FCS, - * opening and closing flags, preserving headroom data. - * parameters: - * skb skb containing original packet (freed upon return) - * Return value: - * pointer to newly allocated skb containing the result frame - * and the original link layer header, NULL on error - */ -static struct sk_buff *HDLC_Encode(struct sk_buff *skb) -{ - 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 - * + room for link layer header - */ - hdlc_skb = dev_alloc_skb(skb->len + stuf_cnt + 6 + skb->mac_len); - if (!hdlc_skb) { - dev_kfree_skb_any(skb); - return NULL; - } - - /* Copy link layer header into new skb */ - skb_reset_mac_header(hdlc_skb); - skb_reserve(hdlc_skb, skb->mac_len); - memcpy(skb_mac_header(hdlc_skb), skb_mac_header(skb), skb->mac_len); - hdlc_skb->mac_len = skb->mac_len; - - /* Add flag sequence in front of everything.. */ - skb_put_u8(hdlc_skb, PPP_FLAG); - - /* Perform byte stuffing while copying data. */ - while (skb->len--) { - if (muststuff(*skb->data)) { - skb_put_u8(hdlc_skb, PPP_ESCAPE); - skb_put_u8(hdlc_skb, (*skb->data++) ^ PPP_TRANS); - } else - skb_put_u8(hdlc_skb, *skb->data++); - } - - /* Finally add FCS (byte stuffed) and flag sequence */ - c = (fcs & 0x00ff); /* least significant byte first */ - if (muststuff(c)) { - skb_put_u8(hdlc_skb, PPP_ESCAPE); - c ^= PPP_TRANS; - } - skb_put_u8(hdlc_skb, c); - - c = ((fcs >> 8) & 0x00ff); - if (muststuff(c)) { - skb_put_u8(hdlc_skb, PPP_ESCAPE); - c ^= PPP_TRANS; - } - skb_put_u8(hdlc_skb, c); - - skb_put_u8(hdlc_skb, PPP_FLAG); - - dev_kfree_skb_any(skb); - return hdlc_skb; -} - -/* - * Encode a data packet into an octet stuffed raw bit inverted frame, - * preserving headroom data. - * parameters: - * skb skb containing original packet (freed upon return) - * Return value: - * pointer to newly allocated skb containing the result frame - * and the original link layer header, NULL on error - */ -static struct sk_buff *iraw_encode(struct sk_buff *skb) -{ - struct sk_buff *iraw_skb; - unsigned char c; - unsigned char *cp; - int len; - - /* size of new buffer (worst case = every byte must be stuffed): - * 2 * original size + room for link layer header - */ - iraw_skb = dev_alloc_skb(2 * skb->len + skb->mac_len); - if (!iraw_skb) { - dev_kfree_skb_any(skb); - return NULL; - } - - /* copy link layer header into new skb */ - skb_reset_mac_header(iraw_skb); - skb_reserve(iraw_skb, skb->mac_len); - memcpy(skb_mac_header(iraw_skb), skb_mac_header(skb), skb->mac_len); - iraw_skb->mac_len = skb->mac_len; - - /* copy and stuff data */ - cp = skb->data; - len = skb->len; - while (len--) { - c = bitrev8(*cp++); - if (c == DLE_FLAG) - skb_put_u8(iraw_skb, c); - skb_put_u8(iraw_skb, c); - } - dev_kfree_skb_any(skb); - return iraw_skb; -} - -/** - * gigaset_m10x_send_skb() - queue an skb for sending - * @bcs: B channel descriptor structure. - * @skb: data to send. - * - * Called by LL to encode and queue an skb for sending, and start - * transmission if necessary. - * Once the payload data has been transmitted completely, gigaset_skb_sent() - * will be called with the skb's link layer header preserved. - * - * Return value: - * number of bytes accepted for sending (skb->len) if ok, - * error code < 0 (eg. -ENOMEM) on error - */ -int gigaset_m10x_send_skb(struct bc_state *bcs, struct sk_buff *skb) -{ - struct cardstate *cs = bcs->cs; - unsigned len = skb->len; - unsigned long flags; - - if (bcs->proto2 == L2_HDLC) - skb = HDLC_Encode(skb); - else - skb = iraw_encode(skb); - if (!skb) { - dev_err(cs->dev, - "unable to allocate memory for encoding!\n"); - return -ENOMEM; - } - - skb_queue_tail(&bcs->squeue, skb); - spin_lock_irqsave(&cs->lock, flags); - if (cs->connected) - tasklet_schedule(&cs->write_tasklet); - spin_unlock_irqrestore(&cs->lock, flags); - - return len; /* ok so far */ -} -EXPORT_SYMBOL_GPL(gigaset_m10x_send_skb); |