Add support for libusb_set_auto_detach_kernel_driver() to the LibUSB v1.0 API.

Approved by:	re (kostikbel)
Requested by:	swills
MFC after:	1 week

lib/libusb/Makefile

@@ -74,6 +74,7 @@ MLINKS += libusb.3 libusb_set_debug.3
 MLINKS += libusb.3 libusb_get_device_list.3
 MLINKS += libusb.3 libusb_free_device_list.3
 MLINKS += libusb.3 libusb_get_bus_number.3
+MLINKS += libusb.3 libusb_get_port_number.3
 MLINKS += libusb.3 libusb_get_device_address.3
 MLINKS += libusb.3 libusb_get_device_speed.3
 MLINKS += libusb.3 libusb_get_max_packet_size.3
@@ -98,6 +99,7 @@ MLINKS += libusb.3 libusb_get_driver_np.3
 MLINKS += libusb.3 libusb_detach_kernel_driver.3
 MLINKS += libusb.3 libusb_detach_kernel_driver_np.3
 MLINKS += libusb.3 libusb_attach_kernel_driver.3
+MLINKS += libusb.3 libusb_set_auto_detach_kernel_driver.3
 MLINKS += libusb.3 libusb_get_device_descriptor.3
 MLINKS += libusb.3 libusb_get_active_config_descriptor.3
 MLINKS += libusb.3 libusb_get_config_descriptor.3

lib/libusb/libusb.3

@@ -298,6 +298,18 @@ LIBUSB_ERROR_NO_DEVICE
 if the device has been disconnected, LIBUSB_ERROR_BUSY if the driver cannot be
 attached because the interface is claimed by a program or driver and a
 LIBUSB_ERROR code on failure.
+.Pp
+.Ft int
+.Fn libusb_set_auto_detach_kernel_driver "libusb_device_handle *devh" "int enable"
+This function enables automatic kernel interface driver detach when an
+interface is claimed.
+When the interface is restored the kernel driver is allowed to be re-attached.
+If the
+.Fa enable
+argument is non-zero the feature is enabled.
+Else disabled.
+Returns 0 on success and a LIBUSB_ERROR code on
+failure.
 .Sh USB DESCRIPTORS
 .Ft int
 .Fn libusb_get_device_descriptor "libusb_device *dev" "libusb_device_descriptor *desc"

lib/libusb/libusb.h

@@ -432,6 +432,7 @@ int	libusb_get_driver(libusb_device_handle * devh, int interface, char *name, in
 int 	libusb_detach_kernel_driver_np(libusb_device_handle * devh, int interface);
 int 	libusb_detach_kernel_driver(libusb_device_handle * devh, int interface);
 int 	libusb_attach_kernel_driver(libusb_device_handle * devh, int interface);
+int	libusb_set_auto_detach_kernel_driver(libusb_device_handle *dev, int enable);
 int	libusb_set_interface_alt_setting(libusb_device_handle * devh, int interface_number, int alternate_setting);
 
 /* USB Descriptors */

lib/libusb/libusb10.c

@@ -637,6 +637,7 @@ int
 libusb_claim_interface(struct libusb20_device *pdev, int interface_number)
 {
 	libusb_device *dev;
+	int err = 0;
 
 	dev = libusb_get_device(pdev);
 	if (dev == NULL)
@@ -645,11 +646,17 @@ libusb_claim_interface(struct libusb20_device *pdev, int interface_number)
 	if (interface_number < 0 || interface_number > 31)
 		return (LIBUSB_ERROR_INVALID_PARAM);
 
+	if (pdev->auto_detach != 0) {
+		err = libusb_detach_kernel_driver(pdev, interface_number);
+		if (err != 0)
+			goto done;
+	}
+
 	CTX_LOCK(dev->ctx);
 	dev->claimed_interfaces |= (1 << interface_number);
 	CTX_UNLOCK(dev->ctx);
-
-	return (0);
+done:
+	return (err);
 }
 
 int
@@ -665,13 +672,19 @@ libusb_release_interface(struct libusb20_device *pdev, int interface_number)
 	if (interface_number < 0 || interface_number > 31)
 		return (LIBUSB_ERROR_INVALID_PARAM);
 
+	if (pdev->auto_detach != 0) {
+		err = libusb_attach_kernel_driver(pdev, interface_number);
+		if (err != 0)
+			goto done;
+	}
+
 	CTX_LOCK(dev->ctx);
 	if (!(dev->claimed_interfaces & (1 << interface_number)))
 		err = LIBUSB_ERROR_NOT_FOUND;
-
-	if (!err)
+	else
 		dev->claimed_interfaces &= ~(1 << interface_number);
 	CTX_UNLOCK(dev->ctx);
+done:
 	return (err);
 }
 
@@ -873,6 +886,12 @@ libusb_attach_kernel_driver(struct libusb20_device *pdev, int interface)
 	return (0);
 }
 
+int
+libusb_set_auto_detach_kernel_driver(libusb_device_handle *dev, int enable)
+{
+	dev->auto_detach = (enable ? 1 : 0);
+}
+
 /* Asynchronous device I/O */
 
 struct libusb_transfer *

lib/libusb/libusb20.c

@@ -601,6 +601,12 @@ libusb20_dev_close(struct libusb20_device *pdev)
 	 */
 	pdev->claimed_interface = 0;
 
+	/*
+	 * The following variable is only used by the libusb v1.0
+	 * compat layer:
+	 */
+	pdev->auto_detach = 0;
+
 	return (error);
 }
 

lib/libusb/libusb20_int.h

@@ -213,6 +213,9 @@ struct libusb20_device {
 	/* claimed interface */
 	uint8_t claimed_interface;
 
+	/* auto detach kernel driver */
+	uint8_t auto_detach;
+  
 	/* device file handle */
 	int	file;