diff options
Diffstat (limited to 'drivers/usb/serial/usb-serial.c')
-rw-r--r-- | drivers/usb/serial/usb-serial.c | 197 |
1 files changed, 135 insertions, 62 deletions
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index f331e2bde88..d595aa5586a 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c @@ -141,6 +141,14 @@ static void destroy_serial(struct kref *kref) if (serial->minor != SERIAL_TTY_NO_MINOR) return_serial(serial); + serial->type->release(serial); + + for (i = 0; i < serial->num_ports; ++i) { + port = serial->port[i]; + if (port) + put_device(&port->dev); + } + /* If this is a "fake" port, we have to clean it up here, as it will * not get cleaned up in port_release() as it was never registered with * the driver core */ @@ -148,9 +156,8 @@ static void destroy_serial(struct kref *kref) for (i = serial->num_ports; i < serial->num_port_pointers; ++i) { port = serial->port[i]; - if (!port) - continue; - port_free(port); + if (port) + port_free(port); } } @@ -238,9 +245,11 @@ static int serial_open (struct tty_struct *tty, struct file *filp) goto bailout_interface_put; mutex_unlock(&serial->disc_mutex); } - mutex_unlock(&port->mutex); - return 0; + /* Now do the correct tty layer semantics */ + retval = tty_port_block_til_ready(&port->port, tty, filp); + if (retval == 0) + return 0; bailout_interface_put: usb_autopm_put_interface(serial->interface); @@ -259,64 +268,89 @@ bailout_serial_put: return retval; } -static void serial_close(struct tty_struct *tty, struct file *filp) +/** + * serial_do_down - shut down hardware + * @port: port to shut down + * + * Shut down a USB port unless it is the console. We never shut down the + * console hardware as it will always be in use. + * + * Don't free any resources at this point + */ +static void serial_do_down(struct usb_serial_port *port) { - struct usb_serial_port *port = tty->driver_data; + struct usb_serial_driver *drv = port->serial->type; struct usb_serial *serial; struct module *owner; - int count; - if (!port) + /* The console is magical, do not hang up the console hardware + or there will be tears */ + if (port->console) return; - dbg("%s - port %d", __func__, port->number); - mutex_lock(&port->mutex); serial = port->serial; owner = serial->type->driver.owner; - if (port->port.count == 0) { - mutex_unlock(&port->mutex); - return; - } + if (drv->close) + drv->close(port); - if (port->port.count == 1) - /* only call the device specific close if this - * port is being closed by the last owner. Ensure we do - * this before we drop the port count. The call is protected - * by the port mutex - */ - serial->type->close(tty, port, filp); - - if (port->port.count == (port->console ? 2 : 1)) { - struct tty_struct *tty = tty_port_tty_get(&port->port); - if (tty) { - /* We must do this before we drop the port count to - zero. */ - if (tty->driver_data) - tty->driver_data = NULL; - tty_port_tty_set(&port->port, NULL); - tty_kref_put(tty); - } - } - - --port->port.count; - count = port->port.count; mutex_unlock(&port->mutex); - put_device(&port->dev); +} + +/** + * serial_do_free - free resources post close/hangup + * @port: port to free up + * + * Do the resource freeing and refcount dropping for the port. We must + * be careful about ordering and we must avoid freeing up the console. + */ + +static void serial_do_free(struct usb_serial_port *port) +{ + struct usb_serial *serial; + struct module *owner; + + /* The console is magical, do not hang up the console hardware + or there will be tears */ + if (port->console) + return; + serial = port->serial; + owner = serial->type->driver.owner; + put_device(&port->dev); /* Mustn't dereference port any more */ - if (count == 0) { - mutex_lock(&serial->disc_mutex); - if (!serial->disconnected) - usb_autopm_put_interface(serial->interface); - mutex_unlock(&serial->disc_mutex); - } + mutex_lock(&serial->disc_mutex); + if (!serial->disconnected) + usb_autopm_put_interface(serial->interface); + mutex_unlock(&serial->disc_mutex); usb_serial_put(serial); - /* Mustn't dereference serial any more */ - if (count == 0) - module_put(owner); + module_put(owner); +} + +static void serial_close(struct tty_struct *tty, struct file *filp) +{ + struct usb_serial_port *port = tty->driver_data; + + dbg("%s - port %d", __func__, port->number); + + + if (tty_port_close_start(&port->port, tty, filp) == 0) + return; + + serial_do_down(port); + tty_port_close_end(&port->port, tty); + tty_port_tty_set(&port->port, NULL); + serial_do_free(port); +} + +static void serial_hangup(struct tty_struct *tty) +{ + struct usb_serial_port *port = tty->driver_data; + serial_do_down(port); + tty_port_hangup(&port->port); + serial_do_free(port); } static int serial_write(struct tty_struct *tty, const unsigned char *buf, @@ -648,6 +682,29 @@ static struct usb_serial_driver *search_serial_device( return NULL; } +static int serial_carrier_raised(struct tty_port *port) +{ + struct usb_serial_port *p = container_of(port, struct usb_serial_port, port); + struct usb_serial_driver *drv = p->serial->type; + if (drv->carrier_raised) + return drv->carrier_raised(p); + /* No carrier control - don't block */ + return 1; +} + +static void serial_dtr_rts(struct tty_port *port, int on) +{ + struct usb_serial_port *p = container_of(port, struct usb_serial_port, port); + struct usb_serial_driver *drv = p->serial->type; + if (drv->dtr_rts) + drv->dtr_rts(p, on); +} + +static const struct tty_port_operations serial_port_ops = { + .carrier_raised = serial_carrier_raised, + .dtr_rts = serial_dtr_rts, +}; + int usb_serial_probe(struct usb_interface *interface, const struct usb_device_id *id) { @@ -841,6 +898,7 @@ int usb_serial_probe(struct usb_interface *interface, if (!port) goto probe_error; tty_port_init(&port->port); + port->port.ops = &serial_port_ops; port->serial = serial; spin_lock_init(&port->lock); mutex_init(&port->mutex); @@ -995,10 +1053,15 @@ int usb_serial_probe(struct usb_interface *interface, dev_set_name(&port->dev, "ttyUSB%d", port->number); dbg ("%s - registering %s", __func__, dev_name(&port->dev)); + port->dev_state = PORT_REGISTERING; retval = device_register(&port->dev); - if (retval) + if (retval) { dev_err(&port->dev, "Error registering port device, " "continuing\n"); + port->dev_state = PORT_UNREGISTERED; + } else { + port->dev_state = PORT_REGISTERED; + } } usb_serial_console_init(debug, minor); @@ -1062,31 +1125,38 @@ void usb_serial_disconnect(struct usb_interface *interface) serial->disconnected = 1; mutex_unlock(&serial->disc_mutex); - /* Unfortunately, many of the sub-drivers expect the port structures - * to exist when their shutdown method is called, so we have to go - * through this awkward two-step unregistration procedure. - */ for (i = 0; i < serial->num_ports; ++i) { port = serial->port[i]; if (port) { struct tty_struct *tty = tty_port_tty_get(&port->port); if (tty) { + /* The hangup will occur asynchronously but + the object refcounts will sort out all the + cleanup */ tty_hangup(tty); tty_kref_put(tty); } kill_traffic(port); cancel_work_sync(&port->work); - device_del(&port->dev); - } - } - serial->type->shutdown(serial); - for (i = 0; i < serial->num_ports; ++i) { - port = serial->port[i]; - if (port) { - put_device(&port->dev); - serial->port[i] = NULL; + if (port->dev_state == PORT_REGISTERED) { + + /* Make sure the port is bound so that the + * driver's port_remove method is called. + */ + if (!port->dev.driver) { + int rc; + + port->dev.driver = + &serial->type->driver; + rc = device_bind_driver(&port->dev); + } + port->dev_state = PORT_UNREGISTERING; + device_del(&port->dev); + port->dev_state = PORT_UNREGISTERED; + } } } + serial->type->disconnect(serial); /* let the last holder of this object * cause it to be cleaned up */ @@ -1135,6 +1205,7 @@ static const struct tty_operations serial_ops = { .open = serial_open, .close = serial_close, .write = serial_write, + .hangup = serial_hangup, .write_room = serial_write_room, .ioctl = serial_ioctl, .set_termios = serial_set_termios, @@ -1147,6 +1218,7 @@ static const struct tty_operations serial_ops = { .proc_fops = &serial_proc_fops, }; + struct tty_driver *usb_serial_tty_driver; static int __init usb_serial_init(void) @@ -1262,7 +1334,8 @@ static void fixup_generic(struct usb_serial_driver *device) set_to_generic_if_null(device, chars_in_buffer); set_to_generic_if_null(device, read_bulk_callback); set_to_generic_if_null(device, write_bulk_callback); - set_to_generic_if_null(device, shutdown); + set_to_generic_if_null(device, disconnect); + set_to_generic_if_null(device, release); } int usb_serial_register(struct usb_serial_driver *driver) |