Fix code to build with recent kernels

This driver code does not build since this commit:

commit 1143832eca8f1d64da7d85642c956ae9d25c69e1
Author: Greg Kroah-Hartman <[email protected]>
Date:   Thu Jun 6 10:32:00 2013 -0700

    USB: serial: ports: add minor and port number

and another set of commits that dropped the use of
interruptible_sleep_on since it is racy.  Here's one such commit:

commit 106fd892bc714a9b7c28daba98a3623a41c32f1a
Author: Arnd Bergmann <[email protected]>
Date:   Wed Feb 26 12:01:44 2014 +0100

    swim3: fix interruptible_sleep_on race

I have patched the code for these changes and verified that it works
correctly on 4.x kernels for my RGUNO, which is an Indian clone of the
Arduino UNO with the CH341 chip.  My patches (past, present and
future) to this code are licensed as GPLv2 (to match the kernel) but I
have no idea what the original code is licensed as, since there is no
indication in the code or the website.

Author: siddhesh

Readme.md

@@ -0,0 +1,31 @@
+CH341 USB Serial Driver for Linux
+=================================
+
+The original code is available for download from:
+
+http://www.wch.cn/download/CH341SER_LINUX_ZIP.html
+
+However, the code does not build since this commit and another commit that
+cleaned up wait_interrupt:
+
+    commit 1143832eca8f1d64da7d85642c956ae9d25c69e1
+    Author: Greg Kroah-Hartman <[email protected]>
+    Date:   Thu Jun 6 10:32:00 2013 -0700
+    
+        USB: serial: ports: add minor and port number
+    
+    and another set of commits that dropped the use of
+    interruptible_sleep_on since it is racy.  Here's one such commit:
+    
+    commit 106fd892bc714a9b7c28daba98a3623a41c32f1a
+    Author: Arnd Bergmann <[email protected]>
+    Date:   Wed Feb 26 12:01:44 2014 +0100
+    
+        swim3: fix interruptible_sleep_on race
+    
+I have patched the code for these changes and verified that it works
+correctly on 4.x kernels for my RGUNO, which is an Indian clone of the
+Arduino UNO with the CH341 chip.  My patches (past, present and
+future) to this code are licensed as GPLv2 (to match the kernel) but I
+have no idea what the original code is licensed as, since there is no
+indication in the code or the website.

ch34x.c

@@ -381,7 +381,7 @@ static void ch34x_set_termios( struct usb_serial_port *port,
 	unsigned short value = 0;
 	unsigned short index = 0;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number);
+	dbg_ch34x("%s - port:%d", __func__, port->port_number);
 
 	spin_lock_irqsave( &priv->lock, flags );
 	if( !priv->termios_initialized ) {
@@ -402,7 +402,7 @@ static void ch34x_set_termios( struct usb_serial_port *port,
 		return;
 
 	cflag = termios->c_cflag;
-	dbg_ch34x("%s (%d) cflag=0x%x\n", __func__, port->number, cflag );
+	dbg_ch34x("%s (%d) cflag=0x%x\n", __func__, port->port_number, cflag );
 
 	// Get the byte size
 	switch( cflag & CSIZE )
@@ -509,7 +509,7 @@ static int ch34x_tiocmget( struct usb_serial_port *port,
 	/*unsigned int msr;*/
 	unsigned int retval;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number);
+	dbg_ch34x("%s - port:%d", __func__, port->port_number);
 
 	if( !usb_get_intfdata( port->serial->interface) ) 
 		return -ENODEV;
@@ -552,7 +552,7 @@ static void ch34x_close( struct usb_serial_port *port,
 	long timeout;
 	wait_queue_t wait;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number);
+	dbg_ch34x("%s - port:%d", __func__, port->port_number);
 
 	// wait for data do drain from the buffer
 	spin_lock_irqsave( &priv->lock, flags );
@@ -623,7 +623,7 @@ static int ch34x_open( struct usb_serial_port *port,
 	struct usb_serial *serial = port->serial;
 	int retval;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number );
+	dbg_ch34x("%s - port:%d", __func__, port->port_number );
 
 	usb_clear_halt( serial->dev, port->write_urb->pipe );
 	usb_clear_halt( serial->dev, port->read_urb->pipe );
@@ -694,7 +694,7 @@ static int ch34x_tiocmset( struct usb_serial_port *port,
 	/*unsigned int mcr = priv->line_control;*/
 	u8 control;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number);
+	dbg_ch34x("%s - port:%d", __func__, port->port_number);
 
 	if( !usb_get_intfdata(port->serial->interface) ) 
 		return -ENODEV;
@@ -723,14 +723,14 @@ static int wait_modem_info( struct usb_serial_port *port,
 	unsigned int status;
 	unsigned int changed;
 
-	dbg_ch34x("%s -port:%d", __func__, port->number);
+	dbg_ch34x("%s -port:%d", __func__, port->port_number);
 
 	spin_lock_irqsave( &priv->lock, flags );
 	prevstatus = priv->line_status;
 	spin_unlock_irqrestore( &priv->lock, flags );
 
 	while(1) {
-		interruptible_sleep_on( &priv->delta_msr_wait );
+		wait_event_interruptible (priv->delta_msr_wait, 0);
 		// see if a signal did it
 		if( signal_pending(current) ) 
 			return -ERESTARTSYS;
@@ -770,13 +770,13 @@ static int ch34x_ioctl( struct usb_serial_port *port,
 {
 	//struct usb_serial_port *port = tty->driver_data;
 #endif
-	dbg_ch34x("%s - port:%d, cmd=0x%04x", __func__, port->number, cmd);
+	dbg_ch34x("%s - port:%d, cmd=0x%04x", __func__, port->port_number, cmd);
 
 	switch(cmd)
 	{
 		// Note here 
 		case TIOCMIWAIT:
-			dbg_ch34x("%s - port:%d TIOCMIWAIT", __func__, port->number);
+			dbg_ch34x("%s - port:%d TIOCMIWAIT", __func__, port->port_number);
 			return wait_modem_info(port, arg);
 		default:
 			dbg_ch34x("%s not supported=0x%04x", __func__, cmd);
@@ -793,7 +793,7 @@ static void ch34x_send( struct usb_serial_port *port )
 	struct ch34x_private *priv = usb_get_serial_port_data( port );
 	unsigned long flags;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number );
+	dbg_ch34x("%s - port:%d", __func__, port->port_number );
 
 	spin_lock_irqsave( &priv->lock, flags );
 	if( priv->write_urb_in_use ) {
@@ -843,7 +843,7 @@ static int ch34x_write( struct usb_serial_port *port,
 	struct ch34x_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;
 
-	dbg_ch34x("%s - port:%d, %d bytes", __func__, port->number, count);
+	dbg_ch34x("%s - port:%d, %d bytes", __func__, port->port_number, count);
 
 	if( !count )
 		return count;
@@ -869,7 +869,7 @@ static int ch34x_write_room( struct usb_serial_port *port )
 	int room = 0;
 	unsigned long flags;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number );
+	dbg_ch34x("%s - port:%d", __func__, port->port_number );
 
 	spin_lock_irqsave( &priv->lock, flags );
 	room = ch34x_buf_space_avail( priv->buf );
@@ -891,7 +891,7 @@ static int ch34x_chars_in_buffer( struct usb_serial_port *port )
 	int chars = 0;
 	unsigned long flags;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number );
+	dbg_ch34x("%s - port:%d", __func__, port->port_number );
 
 	spin_lock_irqsave( &priv->lock, flags );
 	chars = ch34x_buf_data_avail( priv->buf );
@@ -997,7 +997,7 @@ static void ch34x_read_int_callback( struct urb *urb )
 	int status = urb->status;
 	int retval;
 
-	dbg_ch34x("%s port:%d", __func__, port->number );
+	dbg_ch34x("%s port:%d", __func__, port->port_number );
 
 	switch( status ) {
 		case 0: //success
@@ -1042,7 +1042,7 @@ static void ch34x_read_bulk_callback( struct urb *urb )
 	u8 line_status;
 	char tty_flag;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number );
+	dbg_ch34x("%s - port:%d", __func__, port->port_number );
 	if( status ) {
 		dbg_ch34x("%s - urb status=%d", __func__, status );
 		if( status == -EPROTO ) {
@@ -1144,7 +1144,7 @@ static void ch34x_write_bulk_callback( struct urb *urb )
 	int retval;
 	int status = urb->status;
 
-	dbg_ch34x("%s - port:%d", __func__, port->number );
+	dbg_ch34x("%s - port:%d", __func__, port->port_number );
 
 	switch( status ) {
 		case 0: //success