isdn_tty.c

/* $Id: isdn_tty.c,v 1.1.2.3 2004/02/10 01:07:13 keil Exp $
 *
 * Linux ISDN subsystem, tty functions and AT-command emulator (linklevel).
 *
 * Copyright 1994-1999  by Fritz Elfert (fritz@isdn4linux.de)
 * Copyright 1995,96    by Thinking Objects Software GmbH Wuerzburg
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */
#undef ISDN_TTY_STAT_DEBUG

#include <linux/config.h>
#include <linux/isdn.h>
#include <linux/delay.h>
#include "isdn_common.h"
#include "isdn_tty.h"
#ifdef CONFIG_ISDN_AUDIO
#include "isdn_audio.h"
#define VBUF 0x3e0
#define VBUFX (VBUF/16)
#endif

#define FIX_FILE_TRANSFER
#define	DUMMY_HAYES_AT

/* Prototypes */

static int isdn_tty_edit_at(const char *, int, modem_info *);
static void isdn_tty_check_esc(const u_char *, u_char, int, int *, u_long *);
static void isdn_tty_modem_reset_regs(modem_info *, int);
static void isdn_tty_cmd_ATA(modem_info *);
static void isdn_tty_flush_buffer(struct tty_struct *);
static void isdn_tty_modem_result(int, modem_info *);
#ifdef CONFIG_ISDN_AUDIO
static int isdn_tty_countDLE(unsigned char *, int);
#endif

/* Leave this unchanged unless you know what you do! */
#define MODEM_PARANOIA_CHECK
#define MODEM_DO_RESTART

static int bit2si[8] =
{1, 5, 7, 7, 7, 7, 7, 7};
static int si2bit[8] =
{4, 1, 4, 4, 4, 4, 4, 4};

char *isdn_tty_revision = "$Revision: 1.1.2.3 $";


/* isdn_tty_try_read() is called from within isdn_tty_rcv_skb()
 * to stuff incoming data directly into a tty's flip-buffer. This
 * is done to speed up tty-receiving if the receive-queue is empty.
 * This routine MUST be called with interrupts off.
 * Return:
 *  1 = Success
 *  0 = Failure, data has to be buffered and later processed by
 *      isdn_tty_readmodem().
 */
static int
isdn_tty_try_read(modem_info * info, struct sk_buff *skb)
{
	int c;
	int len;
	struct tty_struct *tty;

	if (info->online) {
		if ((tty = info->tty)) {
			if (info->mcr & UART_MCR_RTS) {
				c = TTY_FLIPBUF_SIZE - tty->flip.count;
				len = skb->len
#ifdef CONFIG_ISDN_AUDIO
					+ ISDN_AUDIO_SKB_DLECOUNT(skb)
#endif
					;
				if (c >= len) {
#ifdef CONFIG_ISDN_AUDIO
					if (ISDN_AUDIO_SKB_DLECOUNT(skb))
						while (skb->len--) {
							if (*skb->data == DLE)
								tty_insert_flip_char(tty, DLE, 0);
							tty_insert_flip_char(tty, *skb->data++, 0);
					} else {
#endif
						memcpy(tty->flip.char_buf_ptr,
						       skb->data, len);
						tty->flip.count += len;
						tty->flip.char_buf_ptr += len;
						memset(tty->flip.flag_buf_ptr, 0, len);
						tty->flip.flag_buf_ptr += len;
#ifdef CONFIG_ISDN_AUDIO
					}
#endif
					if (info->emu.mdmreg[REG_CPPP] & BIT_CPPP)
						tty->flip.flag_buf_ptr[len - 1] = 0xff;
					schedule_delayed_work(&tty->flip.work, 1);
					kfree_skb(skb);
					return 1;
				}
			}
		}
	}
	return 0;
}

/* isdn_tty_readmodem() is called periodically from within timer-interrupt.
 * It tries getting received data from the receive queue an stuff it into
 * the tty's flip-buffer.
 */
void
isdn_tty_readmodem(void)
{
	int resched = 0;
	int midx;
	int i;
	int c;
	int r;
	struct tty_struct *tty;
	modem_info *info;

	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
		if ((midx = dev->m_idx[i]) >= 0) {
			info = &dev->mdm.info[midx];
			if (info->online) {
				r = 0;
#ifdef CONFIG_ISDN_AUDIO
				isdn_audio_eval_dtmf(info);
				if ((info->vonline & 1) && (info->emu.vpar[1]))
					isdn_audio_eval_silence(inf