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path: root/drivers/usb/serial/usb-serial.c
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Diffstat (limited to 'drivers/usb/serial/usb-serial.c')
-rw-r--r--drivers/usb/serial/usb-serial.c102
1 files changed, 81 insertions, 21 deletions
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 716f6806cc8..6bf22a28adb 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -59,14 +59,19 @@ static struct usb_driver usb_serial_driver = {
static int debug;
static struct usb_serial *serial_table[SERIAL_TTY_MINORS]; /* initially all NULL */
+static spinlock_t table_lock;
static LIST_HEAD(usb_serial_driver_list);
struct usb_serial *usb_serial_get_by_index(unsigned index)
{
- struct usb_serial *serial = serial_table[index];
+ struct usb_serial *serial;
+
+ spin_lock(&table_lock);
+ serial = serial_table[index];
if (serial)
kref_get(&serial->kref);
+ spin_unlock(&table_lock);
return serial;
}
@@ -78,6 +83,7 @@ static struct usb_serial *get_free_serial (struct usb_serial *serial, int num_po
dbg("%s %d", __FUNCTION__, num_ports);
*minor = 0;
+ spin_lock(&table_lock);
for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
if (serial_table[i])
continue;
@@ -96,8 +102,10 @@ static struct usb_serial *get_free_serial (struct usb_serial *serial, int num_po
dbg("%s - minor base = %d", __FUNCTION__, *minor);
for (i = *minor; (i < (*minor + num_ports)) && (i < SERIAL_TTY_MINORS); ++i)
serial_table[i] = serial;
+ spin_unlock(&table_lock);
return serial;
}
+ spin_unlock(&table_lock);
return NULL;
}
@@ -110,9 +118,11 @@ static void return_serial(struct usb_serial *serial)
if (serial == NULL)
return;
+ spin_lock(&table_lock);
for (i = 0; i < serial->num_ports; ++i) {
serial_table[serial->minor + i] = NULL;
}
+ spin_unlock(&table_lock);
}
static void destroy_serial(struct kref *kref)
@@ -271,7 +281,7 @@ static void serial_close(struct tty_struct *tty, struct file * filp)
static int serial_write (struct tty_struct * tty, const unsigned char *buf, int count)
{
struct usb_serial_port *port = tty->driver_data;
- int retval = -EINVAL;
+ int retval = -ENODEV;
if (!port || port->serial->dev->state == USB_STATE_NOTATTACHED)
goto exit;
@@ -279,6 +289,7 @@ static int serial_write (struct tty_struct * tty, const unsigned char *buf, int
dbg("%s - port %d, %d byte(s)", __FUNCTION__, port->number, count);
if (!port->open_count) {
+ retval = -EINVAL;
dbg("%s - port not opened", __FUNCTION__);
goto exit;
}
@@ -559,15 +570,20 @@ static void port_release(struct device *dev)
port_free(port);
}
-static void port_free(struct usb_serial_port *port)
+static void kill_traffic(struct usb_serial_port *port)
{
usb_kill_urb(port->read_urb);
- usb_free_urb(port->read_urb);
usb_kill_urb(port->write_urb);
- usb_free_urb(port->write_urb);
usb_kill_urb(port->interrupt_in_urb);
- usb_free_urb(port->interrupt_in_urb);
usb_kill_urb(port->interrupt_out_urb);
+}
+
+static void port_free(struct usb_serial_port *port)
+{
+ kill_traffic(port);
+ usb_free_urb(port->read_urb);
+ usb_free_urb(port->write_urb);
+ usb_free_urb(port->interrupt_in_urb);
usb_free_urb(port->interrupt_out_urb);
kfree(port->bulk_in_buffer);
kfree(port->bulk_out_buffer);
@@ -596,6 +612,39 @@ static struct usb_serial * create_serial (struct usb_device *dev,
return serial;
}
+static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
+ struct usb_serial_driver *drv)
+{
+ struct usb_dynid *dynid;
+
+ spin_lock(&drv->dynids.lock);
+ list_for_each_entry(dynid, &drv->dynids.list, node) {
+ if (usb_match_one_id(intf, &dynid->id)) {
+ spin_unlock(&drv->dynids.lock);
+ return &dynid->id;
+ }
+ }
+ spin_unlock(&drv->dynids.lock);
+ return NULL;
+}
+
+static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
+ struct usb_interface *intf)
+{
+ const struct usb_device_id *id;
+
+ id = usb_match_id(intf, drv->id_table);
+ if (id) {
+ dbg("static descriptor matches");
+ goto exit;
+ }
+ id = match_dynamic_id(intf, drv);
+ if (id)
+ dbg("dynamic descriptor matches");
+exit:
+ return id;
+}
+
static struct usb_serial_driver *search_serial_device(struct usb_interface *iface)
{
struct list_head *p;
@@ -605,11 +654,9 @@ static struct usb_serial_driver *search_serial_device(struct usb_interface *ifac
/* Check if the usb id matches a known device */
list_for_each(p, &usb_serial_driver_list) {
t = list_entry(p, struct usb_serial_driver, driver_list);
- id = usb_match_id(iface, t->id_table);
- if (id != NULL) {
- dbg("descriptor matches");
+ id = get_iface_id(t, iface);
+ if (id)
return t;
- }
}
return NULL;
@@ -639,14 +686,17 @@ int usb_serial_probe(struct usb_interface *interface,
int num_ports = 0;
int max_endpoints;
+ lock_kernel(); /* guard against unloading a serial driver module */
type = search_serial_device(interface);
if (!type) {
+ unlock_kernel();
dbg("none matched");
return -ENODEV;
}
serial = create_serial (dev, interface, type);
if (!serial) {
+ unlock_kernel();
dev_err(&interface->dev, "%s - out of memory\n", __FUNCTION__);
return -ENOMEM;
}
@@ -656,16 +706,18 @@ int usb_serial_probe(struct usb_interface *interface,
const struct usb_device_id *id;
if (!try_module_get(type->driver.owner)) {
+ unlock_kernel();
dev_err(&interface->dev, "module get failed, exiting\n");
kfree (serial);
return -EIO;
}
- id = usb_match_id(interface, type->id_table);
+ id = get_iface_id(type, interface);
retval = type->probe(serial, id);
module_put(type->driver.owner);
if (retval) {
+ unlock_kernel();
dbg ("sub driver rejected device");
kfree (serial);
return retval;
@@ -735,6 +787,7 @@ int usb_serial_probe(struct usb_interface *interface,
* properly during a later invocation of usb_serial_probe
*/
if (num_bulk_in == 0 || num_bulk_out == 0) {
+ unlock_kernel();
dev_info(&interface->dev, "PL-2303 hack: descriptors matched but endpoints did not\n");
kfree (serial);
return -ENODEV;
@@ -750,6 +803,7 @@ int usb_serial_probe(struct usb_interface *interface,
if (type == &usb_serial_generic_device) {
num_ports = num_bulk_out;
if (num_ports == 0) {
+ unlock_kernel();
dev_err(&interface->dev, "Generic device with no bulk out, not allowed.\n");
kfree (serial);
return -EIO;
@@ -760,6 +814,7 @@ int usb_serial_probe(struct usb_interface *interface,
/* if this device type has a calc_num_ports function, call it */
if (type->calc_num_ports) {
if (!try_module_get(type->driver.owner)) {
+ unlock_kernel();
dev_err(&interface->dev, "module get failed, exiting\n");
kfree (serial);
return -EIO;
@@ -771,12 +826,6 @@ int usb_serial_probe(struct usb_interface *interface,
num_ports = type->num_ports;
}
- if (get_free_serial (serial, num_ports, &minor) == NULL) {
- dev_err(&interface->dev, "No more free serial devices\n");
- kfree (serial);
- return -ENOMEM;
- }
-
serial->minor = minor;
serial->num_ports = num_ports;
serial->num_bulk_in = num_bulk_in;
@@ -791,6 +840,8 @@ int usb_serial_probe(struct usb_interface *interface,
max_endpoints = max(max_endpoints, num_interrupt_out);
max_endpoints = max(max_endpoints, (int)serial->num_ports);
serial->num_port_pointers = max_endpoints;
+ unlock_kernel();
+
dbg("%s - setting up %d port structures for this device", __FUNCTION__, max_endpoints);
for (i = 0; i < max_endpoints; ++i) {
port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
@@ -925,6 +976,11 @@ int usb_serial_probe(struct usb_interface *interface,
}
}
+ if (get_free_serial (serial, num_ports, &minor) == NULL) {
+ dev_err(&interface->dev, "No more free serial devices\n");
+ goto probe_error;
+ }
+
/* register all of the individual ports with the driver core */
for (i = 0; i < num_ports; ++i) {
port = serial->port[i];
@@ -1002,8 +1058,11 @@ void usb_serial_disconnect(struct usb_interface *interface)
if (serial) {
for (i = 0; i < serial->num_ports; ++i) {
port = serial->port[i];
- if (port && port->tty)
- tty_hangup(port->tty);
+ if (port) {
+ if (port->tty)
+ tty_hangup(port->tty);
+ kill_traffic(port);
+ }
}
/* let the last holder of this object
* cause it to be cleaned up */
@@ -1040,6 +1099,7 @@ static int __init usb_serial_init(void)
return -ENOMEM;
/* Initialize our global data */
+ spin_lock_init(&table_lock);
for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
serial_table[i] = NULL;
}
@@ -1138,7 +1198,7 @@ static void fixup_generic(struct usb_serial_driver *device)
set_to_generic_if_null(device, shutdown);
}
-int usb_serial_register(struct usb_serial_driver *driver)
+int usb_serial_register(struct usb_serial_driver *driver) /* must be called with BKL held */
{
int retval;
@@ -1162,7 +1222,7 @@ int usb_serial_register(struct usb_serial_driver *driver)
}
-void usb_serial_deregister(struct usb_serial_driver *device)
+void usb_serial_deregister(struct usb_serial_driver *device) /* must be called with BKL held */
{
info("USB Serial deregistering driver %s", device->description);
list_del(&device->driver_list);