Commit 89ccbdc9 authored by David Brownell's avatar David Brownell Committed by Greg Kroah-Hartman
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[PATCH] USB: otg hub support is optional 



USB OTG devices are not required to support external hubs.  This adds a
configuration option to disable that support.

Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 4d45e218

drivers/usb/core/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -99,4 +99,11 @@ config USB_OTG_WHITELIST 
	  normal Linux-USB hosts do (other than the warning), and is

	  convenient for many stages of product development.



config USB_OTG_BLACKLIST_HUB

	bool "Disable external hubs"

	depends on USB_OTG

	help

	  If you say Y here, then Linux will refuse to enumerate

	  external hubs.  OTG hosts are allowed to reduce hardware

	  and software costs by not supporting external hubs.

drivers/usb/core/hub.c

+7 −0
Original line number Diff line number Diff line
@@ -836,6 +836,13 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) 
	desc = intf->cur_altsetting;

	hdev = interface_to_usbdev(intf);



#ifdef	CONFIG_USB_OTG_BLACKLIST_HUB

	if (hdev->parent) {

		dev_warn(&intf->dev, "ignoring external hub\n");

		return -ENODEV;

	}

#endif



	/* Some hubs have a subclass of 1, which AFAICT according to the */

	/*  specs is not defined, but it works */

	if ((desc->desc.bInterfaceSubClass != 0) &&

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