ChangeSet 1.1119.3.3, 2003/09/04 08:52:26-07:00, greg@kroah.com

[PATCH] USB: backport some pl2303 B0 fixes.

Also add proper locking for the port structure.  This comes from the 2.6
kernel tree too.


 drivers/usb/serial/pl2303.c |  111 ++++++++++++++++++++++++++++++++------------
 1 files changed, 81 insertions(+), 30 deletions(-)


diff -Nru a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
--- a/drivers/usb/serial/pl2303.c	Fri Sep  5 17:10:55 2003
+++ b/drivers/usb/serial/pl2303.c	Fri Sep  5 17:10:55 2003
@@ -153,7 +153,8 @@
 	.shutdown =		pl2303_shutdown,
 };
 
-struct pl2303_private { 
+struct pl2303_private {
+	spinlock_t lock;
 	u8 line_control;
 	u8 line_status;
 	u8 termios_initialized;
@@ -170,7 +171,8 @@
 		if (!priv)
 			return -ENOMEM;
 		memset (priv, 0x00, sizeof (struct pl2303_private));
-		serial->port[i].private = priv;
+		spin_lock_init(&priv->lock);
+		usb_set_serial_port_data(&serial->port[i], priv);
 	}
 	return 0;
 }
@@ -223,25 +225,30 @@
 static void pl2303_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 {
 	struct usb_serial *serial = port->serial;
-	struct pl2303_private *priv;
+	struct pl2303_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
 	unsigned int cflag;
 	unsigned char *buf;
 	int baud;
 	int i;
+	u8 control;
 
 	dbg("%s -  port %d, initialized = %d", __FUNCTION__, port->number, 
-	     ((struct pl2303_private *) port->private)->termios_initialized);
+	     priv->termios_initialized);
 
 	if ((!port->tty) || (!port->tty->termios)) {
 		dbg("%s - no tty structures", __FUNCTION__);
 		return;
 	}
 
-	if (!(((struct pl2303_private *) port->private)->termios_initialized)) {
+	spin_lock_irqsave(&priv->lock, flags);
+	if (!priv->termios_initialized) {
 		*(port->tty->termios) = tty_std_termios;
 		port->tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
-		((struct pl2303_private *) port->private)->termios_initialized = 1;
+		priv->termios_initialized = 1;
 	}
+	spin_unlock_irqrestore(&priv->lock, flags);
+
 	cflag = port->tty->termios->c_cflag;
 	/* check that they really want us to change something */
 	if (old_termios) {
@@ -341,13 +348,19 @@
 			     0, 0, buf, 7, 100);
 	dbg ("0x21:0x20:0:0  %d", i);
 
-	if (cflag && CBAUD) {
-		priv = port->private;
-		if ((cflag && CBAUD) == B0)
-			priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
-		else
-			priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
-		set_control_lines (serial->dev, priv->line_control);
+	/* change control lines if we are switching to or from B0 */
+	spin_lock_irqsave(&priv->lock, flags);
+	control = priv->line_control;
+	if ((cflag & CBAUD) == B0)
+		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
+	else
+		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
+	if (control != priv->line_control) {
+		control = priv->line_control;
+		spin_unlock_irqrestore(&priv->lock, flags);
+		set_control_lines(serial->dev, control);
+	} else {
+		spin_unlock_irqrestore(&priv->lock, flags);
 	}
 	
 	buf[0] = buf[1] = buf[2] = buf[3] = buf[4] = buf[5] = buf[6] = 0;
@@ -435,6 +448,7 @@
 {
 	struct usb_serial *serial;
 	struct pl2303_private *priv;
+	unsigned long flags;
 	unsigned int c_cflag;
 	int result;
 
@@ -451,10 +465,11 @@
 			c_cflag = port->tty->termios->c_cflag;
 			if (c_cflag & HUPCL) {
 				/* drop DTR and RTS */
-				priv = port->private;
+				priv = usb_get_serial_port_data(port);
+				spin_lock_irqsave(&priv->lock, flags);
 				priv->line_control = 0;
-				set_control_lines (port->serial->dev,
-						   priv->line_control);
+				spin_unlock_irqrestore (&priv->lock, flags);
+				set_control_lines (port->serial->dev, 0);
 			}
 		}
 
@@ -482,12 +497,15 @@
 
 static int set_modem_info (struct usb_serial_port *port, unsigned int cmd, unsigned int *value)
 {
-	struct pl2303_private *priv = port->private;
+	struct pl2303_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
 	unsigned int arg;
+	u8 control;
 
 	if (copy_from_user(&arg, value, sizeof(int)))
 		return -EFAULT;
 
+	spin_lock_irqsave (&priv->lock, flags);
 	switch (cmd) {
 		case TIOCMBIS:
 			if (arg & TIOCM_RTS)
@@ -511,17 +529,25 @@
 			priv->line_control |= ((arg & TIOCM_DTR) ? CONTROL_DTR : 0);
 			break;
 	}
+	control = priv->line_control;
+	spin_unlock_irqrestore (&priv->lock, flags);
 
-	return set_control_lines (port->serial->dev, priv->line_control);
+	return set_control_lines (port->serial->dev, control);
 }
 
 static int get_modem_info (struct usb_serial_port *port, unsigned int *value)
 {
-	struct pl2303_private *priv = port->private;
-	unsigned int mcr = priv->line_control;
-	unsigned int status = priv->line_status;
+	struct pl2303_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+	unsigned int mcr;
+	unsigned int status;
 	unsigned int result;
 
+	spin_lock_irqsave (&priv->lock, flags);
+	mcr = priv->line_control;
+	status = priv->line_status;
+	spin_unlock_irqrestore (&priv->lock, flags);
+
 	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
 		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
 		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
@@ -560,7 +586,6 @@
 	return -ENOIOCTLCMD;
 }
 
-
 static void pl2303_break_ctl (struct usb_serial_port *port, int break_state)
 {
 	struct usb_serial *serial = port->serial;
@@ -589,8 +614,10 @@
 
 	dbg("%s", __FUNCTION__);
 
-	for (i = 0; i < serial->num_ports; ++i)
-		kfree (serial->port[i].private);
+	for (i = 0; i < serial->num_ports; ++i) {
+		kfree (usb_get_serial_port_data(&serial->port[i]));
+		usb_set_serial_port_data(&serial->port[i], NULL);
+	}		
 }
 
 
@@ -598,17 +625,30 @@
 {
 	struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
 	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
-	struct pl2303_private *priv = port->private;
+	struct pl2303_private *priv = usb_get_serial_port_data(port);
 	unsigned char *data = urb->transfer_buffer;
+	unsigned long flags;
+
+	dbg("%s (%d)", __FUNCTION__, port->number);
 
 	/* ints auto restart... */
 
-	if (!serial) {
+	switch (urb->status) {
+	case 0:
+		/* success */
+		break;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+		/* this urb is terminated, clean up */
+		dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
+		return;
+	default:
+		dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
 		return;
 	}
 
-	if (urb->status) {
-		urb->status = 0;
+	if (!serial) {
 		return;
 	}
 
@@ -618,7 +658,9 @@
 		return;
 
 	/* Save off the uart status for others to look at */
+	spin_lock_irqsave(&priv->lock, flags);
 	priv->line_status = data[UART_STATE];
+	spin_unlock_irqrestore(&priv->lock, flags);
 
 	return;
 }
@@ -628,9 +670,10 @@
 {
 	struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
 	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
-	struct pl2303_private *priv = port->private;
+	struct pl2303_private *priv = usb_get_serial_port_data(port);
 	struct tty_struct *tty;
 	unsigned char *data = urb->transfer_buffer;
+	unsigned long flags;
 	int i;
 	int result;
 	u8 status;
@@ -670,7 +713,10 @@
 
 	/* get tty_flag from status */
 	tty_flag = TTY_NORMAL;
+
+	spin_lock_irqsave(&priv->lock, flags);
 	status = priv->line_status;
+	spin_unlock_irqrestore(&priv->lock, flags);
 
 	/* break takes precedence over parity, */
 	/* which takes precedence over framing errors */
@@ -745,9 +791,14 @@
 
 static int __init pl2303_init (void)
 {
-	usb_serial_register (&pl2303_device);
+	int retval;
+	retval = usb_serial_register(&pl2303_device);
+	if (retval)
+		goto failed_usb_serial_register;
 	info(DRIVER_DESC " " DRIVER_VERSION);
 	return 0;
+failed_usb_serial_register:
+	return retval;
 }