synclink_cs.c

linux-2.6.15.6

	info->flags |= ASYNC_INITIALIZED;
	
	return 0;
}

/* Called by mgslpc_close() and mgslpc_hangup() to shutdown hardware
 */
static void shutdown(MGSLPC_INFO * info)
{
	unsigned long flags;
	
	if (!(info->flags & ASYNC_INITIALIZED))
		return;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_shutdown(%s)\n",
			 __FILE__,__LINE__, info->device_name );

	/* clear status wait queue because status changes */
	/* can't happen after shutting down the hardware */
	wake_up_interruptible(&info->status_event_wait_q);
	wake_up_interruptible(&info->event_wait_q);

	del_timer(&info->tx_timer);	

	if (info->tx_buf) {
		free_page((unsigned long) info->tx_buf);
		info->tx_buf = NULL;
	}

	spin_lock_irqsave(&info->lock,flags);

	rx_stop(info);
	tx_stop(info);

	/* TODO:disable interrupts instead of reset to preserve signal states */
	reset_device(info);
	
 	if (!info->tty || info->tty->termios->c_cflag & HUPCL) {
 		info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
		set_signals(info);
	}
	
	spin_unlock_irqrestore(&info->lock,flags);

	release_resources(info);	
	
	if (info->tty)
		set_bit(TTY_IO_ERROR, &info->tty->flags);

	info->flags &= ~ASYNC_INITIALIZED;
}

static void mgslpc_program_hw(MGSLPC_INFO *info)
{
	unsigned long flags;

	spin_lock_irqsave(&info->lock,flags);
	
	rx_stop(info);
	tx_stop(info);
	info->tx_count = info->tx_put = info->tx_get = 0;
	
	if (info->params.mode == MGSL_MODE_HDLC || info->netcount)
		hdlc_mode(info);
	else
		async_mode(info);
		
	set_signals(info);
	
	info->dcd_chkcount = 0;
	info->cts_chkcount = 0;
	info->ri_chkcount = 0;
	info->dsr_chkcount = 0;

	irq_enable(info, CHB, IRQ_DCD | IRQ_CTS);
	port_irq_enable(info, (unsigned char) PVR_DSR | PVR_RI);
	get_signals(info);
		
	if (info->netcount || info->tty->termios->c_cflag & CREAD)
		rx_start(info);
		
	spin_unlock_irqrestore(&info->lock,flags);
}

/* Reconfigure adapter based on new parameters
 */
static void mgslpc_change_params(MGSLPC_INFO *info)
{
	unsigned cflag;
	int bits_per_char;

	if (!info->tty || !info->tty->termios)
		return;
		
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_change_params(%s)\n",
			 __FILE__,__LINE__, info->device_name );
			 
	cflag = info->tty->termios->c_cflag;

	/* if B0 rate (hangup) specified then negate DTR and RTS */
	/* otherwise assert DTR and RTS */
 	if (cflag & CBAUD)
		info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
	else
		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
	
	/* byte size and parity */
	
	switch (cflag & CSIZE) {
	case CS5: info->params.data_bits = 5; break;
	case CS6: info->params.data_bits = 6; break;
	case CS7: info->params.data_bits = 7; break;
	case CS8: info->params.data_bits = 8; break;
	default:  info->params.data_bits = 7; break;
	}
	      
	if (cflag & CSTOPB)
		info->params.stop_bits = 2;
	else
		info->params.stop_bits = 1;

	info->params.parity = ASYNC_PARITY_NONE;
	if (cflag & PARENB) {
		if (cflag & PARODD)
			info->params.parity = ASYNC_PARITY_ODD;
		else
			info->params.parity = ASYNC_PARITY_EVEN;
#ifdef CMSPAR
		if (cflag & CMSPAR)
			info->params.parity = ASYNC_PARITY_SPACE;
#endif
	}

	/* calculate number of jiffies to transmit a full
	 * FIFO (32 bytes) at specified data rate
	 */
	bits_per_char = info->params.data_bits + 
			info->params.stop_bits + 1;

	/* if port data rate is set to 460800 or less then
	 * allow tty settings to override, otherwise keep the
	 * current data rate.
	 */
	if (info->params.data_rate <= 460800) {
		info->params.data_rate = tty_get_baud_rate(info->tty);
	}
	
	if ( info->params.data_rate ) {
		info->timeout = (32*HZ*bits_per_char) / 
				info->params.data_rate;
	}
	info->timeout += HZ/50;		/* Add .02 seconds of slop */

	if (cflag & CRTSCTS)
		info->flags |= ASYNC_CTS_FLOW;
	else
		info->flags &= ~ASYNC_CTS_FLOW;
		
	if (cflag & CLOCAL)
		info->flags &= ~ASYNC_CHECK_CD;
	else
		info->flags |= ASYNC_CHECK_CD;

	/* process tty input control flags */
	
	info->read_status_mask = 0;
	if (I_INPCK(info->tty))
		info->read_status_mask |= BIT7 | BIT6;
	if (I_IGNPAR(info->tty))
		info->ignore_status_mask |= BIT7 | BIT6;

	mgslpc_program_hw(info);
}

/* Add a character to the transmit buffer
 */
static void mgslpc_put_char(struct tty_struct *tty, unsigned char ch)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;

	if (debug_level >= DEBUG_LEVEL_INFO) {
		printk( "%s(%d):mgslpc_put_char(%d) on %s\n",
			__FILE__,__LINE__,ch,info->device_name);
	}

	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_put_char"))
		return;

	if (!tty || !info->tx_buf)
		return;

	spin_lock_irqsave(&info->lock,flags);
	
	if (info->params.mode == MGSL_MODE_ASYNC || !info->tx_active) {
		if (info->tx_count < TXBUFSIZE - 1) {
			info->tx_buf[info->tx_put++] = ch;
			info->tx_put &= TXBUFSIZE-1;
			info->tx_count++;
		}
	}
	
	spin_unlock_irqrestore(&info->lock,flags);
}

/* Enable transmitter so remaining characters in the
 * transmit buffer are sent.
 */
static void mgslpc_flush_chars(struct tty_struct *tty)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;
				
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk( "%s(%d):mgslpc_flush_chars() entry on %s tx_count=%d\n",
			__FILE__,__LINE__,info->device_name,info->tx_count);
	
	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_flush_chars"))
		return;

	if (info->tx_count <= 0 || tty->stopped ||
	    tty->hw_stopped || !info->tx_buf)
		return;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk( "%s(%d):mgslpc_flush_chars() entry on %s starting transmitter\n",
			__FILE__,__LINE__,info->device_name);

	spin_lock_irqsave(&info->lock,flags);
	if (!info->tx_active)
	 	tx_start(info);
	spin_unlock_irqrestore(&info->lock,flags);
}

/* Send a block of data
 * 	
 * Arguments:
 * 
 * tty        pointer to tty information structure
 * buf	      pointer to buffer containing send data
 * count      size of send data in bytes
 * 	
 * Returns: number of characters written
 */
static int mgslpc_write(struct tty_struct * tty,
			const unsigned char *buf, int count)
{
	int c, ret = 0;
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;
	
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk( "%s(%d):mgslpc_write(%s) count=%d\n",
			__FILE__,__LINE__,info->device_name,count);
	
	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_write") ||
	    !tty || !info->tx_buf)
		goto cleanup;

	if (info->params.mode == MGSL_MODE_HDLC) {
		if (count > TXBUFSIZE) {
			ret = -EIO;
			goto cleanup;
		}
		if (info->tx_active)
			goto cleanup;
		else if (info->tx_count)
			goto start;
	}

	for (;;) {
		c = min(count,
			min(TXBUFSIZE - info->tx_count - 1,
			    TXBUFSIZE - info->tx_put));
		if (c <= 0)
			break;
			
		memcpy(info->tx_buf + info->tx_put, buf, c);

		spin_lock_irqsave(&info->lock,flags);
		info->tx_put = (info->tx_put + c) & (TXBUFSIZE-1);
		info->tx_count += c;
		spin_unlock_irqrestore(&info->lock,flags);

		buf += c;
		count -= c;
		ret += c;
	}
start:
 	if (info->tx_count && !tty->stopped && !tty->hw_stopped) {
		spin_lock_irqsave(&info->lock,flags);
		if (!info->tx_active)
		 	tx_start(info);
		spin_unlock_irqrestore(&info->lock,flags);
 	}
cleanup:	
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk( "%s(%d):mgslpc_write(%s) returning=%d\n",
			__FILE__,__LINE__,info->device_name,ret);
	return ret;
}

/* Return the count of free bytes in transmit buffer
 */
static int mgslpc_write_room(struct tty_struct *tty)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	int ret;
				
	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_write_room"))
		return 0;

	if (info->params.mode == MGSL_MODE_HDLC) {
		/* HDLC (frame oriented) mode */
		if (info->tx_active)
			return 0;
		else
			return HDLC_MAX_FRAME_SIZE;
	} else {
		ret = TXBUFSIZE - info->tx_count - 1;
		if (ret < 0)
			ret = 0;
	}
	
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_write_room(%s)=%d\n",
			 __FILE__,__LINE__, info->device_name, ret);
	return ret;
}

/* Return the count of bytes in transmit buffer
 */
static int mgslpc_chars_in_buffer(struct tty_struct *tty)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	int rc;
		 
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_chars_in_buffer(%s)\n",
			 __FILE__,__LINE__, info->device_name );
			 
	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_chars_in_buffer"))
		return 0;
		
	if (info->params.mode == MGSL_MODE_HDLC)
		rc = info->tx_active ? info->max_frame_size : 0;
	else
		rc = info->tx_count;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_chars_in_buffer(%s)=%d\n",
			 __FILE__,__LINE__, info->device_name, rc);
			 
	return rc;
}

/* Discard all data in the send buffer
 */
static void mgslpc_flush_buffer(struct tty_struct *tty)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;
	
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_flush_buffer(%s) entry\n",
			 __FILE__,__LINE__, info->device_name );
	
	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_flush_buffer"))
		return;
		
	spin_lock_irqsave(&info->lock,flags); 
	info->tx_count = info->tx_put = info->tx_get = 0;
	del_timer(&info->tx_timer);	
	spin_unlock_irqrestore(&info->lock,flags);

	wake_up_interruptible(&tty->write_wait);
	tty_wakeup(tty);
}

/* Send a high-priority XON/XOFF character
 */
static void mgslpc_send_xchar(struct tty_struct *tty, char ch)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;

	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_send_xchar(%s,%d)\n",
			 __FILE__,__LINE__, info->device_name, ch );
			 
	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_send_xchar"))
		return;

	info->x_char = ch;
	if (ch) {
		spin_lock_irqsave(&info->lock,flags);
		if (!info->tx_enabled)
		 	tx_start(info);
		spin_unlock_irqrestore(&info->lock,flags);
	}
}

/* Signal remote device to throttle send data (our receive data)
 */
static void mgslpc_throttle(struct tty_struct * tty)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;
	
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_throttle(%s) entry\n",
			 __FILE__,__LINE__, info->device_name );

	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_throttle"))
		return;
	
	if (I_IXOFF(tty))
		mgslpc_send_xchar(tty, STOP_CHAR(tty));
 
 	if (tty->termios->c_cflag & CRTSCTS) {
		spin_lock_irqsave(&info->lock,flags);
		info->serial_signals &= ~SerialSignal_RTS;
	 	set_signals(info);
		spin_unlock_irqrestore(&info->lock,flags);
	}
}

/* Signal remote device to stop throttling send data (our receive data)
 */
static void mgslpc_unthrottle(struct tty_struct * tty)
{
	MGSLPC_INFO *info = (MGSLPC_INFO *)tty->driver_data;
	unsigned long flags;
	
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("%s(%d):mgslpc_unthrottle(%s) entry\n",
			 __FILE__,__LINE__, info->device_name );

	if (mgslpc_paranoia_check(info, tty->name, "mgslpc_unthrottle"))
		return;
	
	if (I_IXOFF(tty)) {
		if (info->x_char)
			info->x_char = 0;
		else
			mgslpc_send_xchar(tty, START_CHAR(tty));
	}
	
 	if (tty->termios->c_cflag & CRTSCTS) {
		spin_lock_irqsave(&info->lock,flags);
		info->serial_signals |= SerialSignal_RTS;
	 	set_signals(info);
		spin_unlock_irqrestore(&info->lock,flags);
	}
}

/* get the current serial statistics
 */
static int get_stats(MGSLPC_INFO * info, struct mgsl_icount __user *user_icount)
{
	int err;
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("get_params(%s)\n", info->device_name);
	if (!user_icount) {
		memset(&info->icount, 0, sizeof(info->icount));
	} else {
		COPY_TO_USER(err, user_icount, &info->icount, sizeof(struct mgsl_icount));
		if (err)
			return -EFAULT;
	}
	return 0;
}

/* get the current serial parameters
 */
static int get_params(MGSLPC_INFO * info, MGSL_PARAMS __user *user_params)
{
	int err;
	if (debug_level >= DEBUG_LEVEL_INFO)
		printk("get_params(%s)\n", info->device_name);
	COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
	if (err)
		return -EFAULT;
	return 0;
}

/* set the serial parameters
 * 	
 * Arguments:
 * 
 * 	info		pointer to device instance data
 * 	new_params	user buffer containing new serial params
 *