USB: serial core should respect driver requirements
This patch (as997) fixes a bug in the USB serial core. The core needs
to pay attention to drivers' requirements regarding the number and
type of endpoints a device has.
At the same time, the patch changes the NUM_DONT_CARE constant (which
is stored in a single-byte field) from -1 to a safer, unsigned value.
It also improves the kerneldoc for several fields in the
usb_serial_driver structure.
Finally, the patch replaces a list_for_each() with list_for_each_entry().
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 26e015c..4b1bd7d 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -662,16 +662,14 @@
static struct usb_serial_driver *search_serial_device(struct usb_interface *iface)
{
- struct list_head *p;
const struct usb_device_id *id;
- struct usb_serial_driver *t;
+ struct usb_serial_driver *drv;
/* 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 = get_iface_id(t, iface);
+ list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
+ id = get_iface_id(drv, iface);
if (id)
- return t;
+ return drv;
}
return NULL;
@@ -811,9 +809,6 @@
/* END HORRIBLE HACK FOR PL2303 */
#endif
- /* found all that we need */
- dev_info(&interface->dev, "%s converter detected\n", type->description);
-
#ifdef CONFIG_USB_SERIAL_GENERIC
if (type == &usb_serial_generic_device) {
num_ports = num_bulk_out;
@@ -847,6 +842,24 @@
serial->num_interrupt_in = num_interrupt_in;
serial->num_interrupt_out = num_interrupt_out;
+ /* check that the device meets the driver's requirements */
+ if ((type->num_interrupt_in != NUM_DONT_CARE &&
+ type->num_interrupt_in != num_interrupt_in)
+ || (type->num_interrupt_out != NUM_DONT_CARE &&
+ type->num_interrupt_out != num_interrupt_out)
+ || (type->num_bulk_in != NUM_DONT_CARE &&
+ type->num_bulk_in != num_bulk_in)
+ || (type->num_bulk_out != NUM_DONT_CARE &&
+ type->num_bulk_out != num_bulk_out)) {
+ dbg("wrong number of endpoints");
+ kfree(serial);
+ return -EIO;
+ }
+
+ /* found all that we need */
+ dev_info(&interface->dev, "%s converter detected\n",
+ type->description);
+
/* create our ports, we need as many as the max endpoints */
/* we don't use num_ports here cauz some devices have more endpoint pairs than ports */
max_endpoints = max(num_bulk_in, num_bulk_out);
diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h
index e8b8928..488ce12 100644
--- a/include/linux/usb/serial.h
+++ b/include/linux/usb/serial.h
@@ -141,7 +141,7 @@
};
#define to_usb_serial(d) container_of(d, struct usb_serial, kref)
-#define NUM_DONT_CARE (-1)
+#define NUM_DONT_CARE 99
/* get and set the serial private data pointer helper functions */
static inline void *usb_get_serial_data (struct usb_serial *serial)
@@ -160,12 +160,18 @@
* in the syslog messages when a device is inserted or removed.
* @id_table: pointer to a list of usb_device_id structures that define all
* of the devices this structure can support.
- * @num_interrupt_in: the number of interrupt in endpoints this device will
- * have.
- * @num_interrupt_out: the number of interrupt out endpoints this device will
- * have.
- * @num_bulk_in: the number of bulk in endpoints this device will have.
- * @num_bulk_out: the number of bulk out endpoints this device will have.
+ * @num_interrupt_in: If a device doesn't have this many interrupt-in
+ * endpoints, it won't be sent to the driver's attach() method.
+ * (But it might still be sent to the probe() method.)
+ * @num_interrupt_out: If a device doesn't have this many interrupt-out
+ * endpoints, it won't be sent to the driver's attach() method.
+ * (But it might still be sent to the probe() method.)
+ * @num_bulk_in: If a device doesn't have this many bulk-in
+ * endpoints, it won't be sent to the driver's attach() method.
+ * (But it might still be sent to the probe() method.)
+ * @num_bulk_out: If a device doesn't have this many bulk-out
+ * endpoints, it won't be sent to the driver's attach() method.
+ * (But it might still be sent to the probe() method.)
* @num_ports: the number of different ports this device will have.
* @calc_num_ports: pointer to a function to determine how many ports this
* device has dynamically. It will be called after the probe()
