Commit a1cd7e99 authored by Oliver Neukum's avatar Oliver Neukum Committed by Greg Kroah-Hartman
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USB: stop io performed by mos7720 upon close() 



This fixes a problem where the mos7720 driver will make io to a device from
which it has been logically disconnected. It does so by introducing a flag by
which the generic usb serial code can signal the subdrivers their
disconnection and appropriate locking.

Signed-off-by: default avatarOliver Neukum <oneukum@suse.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 828d55c5

drivers/usb/serial/mos7720.c

+18 −15
Original line number Diff line number Diff line
@@ -564,14 +564,16 @@ static void mos7720_close(struct usb_serial_port *port, struct file *filp) 
	}



	/* While closing port, shutdown all bulk read, write  *

	 * and interrupt read if they exists                  */

	if (serial->dev) {

	 * and interrupt read if they exists, otherwise nop   */

	dbg("Shutdown bulk write");

	usb_kill_urb(port->write_urb);

	dbg("Shutdown bulk read");

	usb_kill_urb(port->read_urb);

	}



	mutex_lock(&serial->disc_mutex);

	/* these commands must not be issued if the device has

	 * been disconnected */

	if (!serial->disconnected) {

		data = 0x00;

		send_mos_cmd(serial, MOS_WRITE, port->number - port->serial->minor,

			     0x04, &data);
@@ -579,7 +581,8 @@ static void mos7720_close(struct usb_serial_port *port, struct file *filp) 
		data = 0x00;

		send_mos_cmd(serial, MOS_WRITE, port->number - port->serial->minor,

			     0x01, &data);



	}

	mutex_unlock(&serial->disc_mutex);

	mos7720_port->open = 0;



	dbg("Leaving %s", __FUNCTION__);

drivers/usb/serial/usb-serial.c

+14 −14
Original line number Diff line number Diff line
@@ -634,6 +634,7 @@ static struct usb_serial * create_serial (struct usb_device *dev, 
	serial->type = driver;

	serial->interface = interface;

	kref_init(&serial->kref);

	mutex_init(&serial->disc_mutex);



	return serial;

}
@@ -1089,8 +1090,10 @@ void usb_serial_disconnect(struct usb_interface *interface) 
	usb_serial_console_disconnect(serial);

	dbg ("%s", __FUNCTION__);



	mutex_lock(&serial->disc_mutex);

	usb_set_intfdata (interface, NULL);

	if (serial) {

	/* must set a flag, to signal subdrivers */

	serial->disconnected = 1;

	for (i = 0; i < serial->num_ports; ++i) {

		port = serial->port[i];

		if (port) {
@@ -1101,8 +1104,8 @@ void usb_serial_disconnect(struct usb_interface *interface) 
	}

	/* let the last holder of this object

	 * cause it to be cleaned up */

	mutex_unlock(&serial->disc_mutex);

	usb_serial_put(serial);

	}

	dev_info(dev, "device disconnected\n");

}
@@ -1112,9 +1115,6 @@ int usb_serial_suspend(struct usb_interface *intf, pm_message_t message) 
	struct usb_serial_port *port;

	int i, r = 0;



	if (!serial) /* device has been disconnected */

		return 0;



	for (i = 0; i < serial->num_ports; ++i) {

		port = serial->port[i];

		if (port)

include/linux/usb/serial.h

+2 −0
Original line number Diff line number Diff line
@@ -129,6 +129,7 @@ struct usb_serial { 
	struct usb_device *		dev;

	struct usb_serial_driver *	type;

	struct usb_interface *		interface;

	unsigned char			disconnected;

	unsigned char			minor;

	unsigned char			num_ports;

	unsigned char			num_port_pointers;
@@ -138,6 +139,7 @@ struct usb_serial { 
	char				num_bulk_out;

	struct usb_serial_port *	port[MAX_NUM_PORTS];

	struct kref			kref;

	struct mutex			disc_mutex;

	void *				private;

};

#define to_usb_serial(d) container_of(d, struct usb_serial, kref)

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