linux-imx

/*

 * 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/isdn.h>

#include <linux/serial.h> /* ASYNC_* flags */

#include <linux/slab.h>

#include <linux/delay.h>

#include <linux/mutex.h>

#include <linux/sched/signal.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 DEFINE_MUTEX(modem_info_mutex);

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};

​

/* 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)

{

    struct tty_port *port = &info->port;

    int c;

    int len;

    char last;

​

    if (!info->online)

        return 0;

​

    if (!(info->mcr & UART_MCR_RTS))

        return 0;

​

    len = skb->len

#ifdef CONFIG_ISDN_AUDIO

        + ISDN_AUDIO_SKB_DLECOUNT(skb)

#endif

        ;

​

    c = tty_buffer_request_room(port, len);

    if (c < len)

        return 0;

​

#ifdef CONFIG_ISDN_AUDIO

    if (ISDN_AUDIO_SKB_DLECOUNT(skb)) {

        int l = skb->len;

        unsigned char *dp = skb->data;

        while (--l) {

            if (*dp == DLE)

                tty_insert_flip_char(port, DLE, 0);

            tty_insert_flip_char(port, *dp++, 0);