From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751363AbdFYIIY (ORCPT ); Sun, 25 Jun 2017 04:08:24 -0400 Received: from mail-lf0-f67.google.com ([209.85.215.67]:35498 "EHLO mail-lf0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751114AbdFYIIV (ORCPT ); Sun, 25 Jun 2017 04:08:21 -0400 Date: Sun, 25 Jun 2017 11:08:14 +0300 From: Eugene Korenevsky To: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Cc: Greg Kroah-Hartman , Baolin Wang Subject: [PATCH] [PATCH v7] USB hub_probe: rework ugly goto-into-compound-statement Message-ID: <20170625080814.GA13512@vnote> Mail-Followup-To: Eugene Korenevsky , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, Greg Kroah-Hartman , Baolin Wang MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.8.3 (2017-05-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rework smelling code (goto inside compound statement). Perhaps this is legacy. Anyway such code is not appropriate for Linux kernel. Signed-off-by: Eugene Korenevsky --- Changes in v7: rename hub_check_descriptor_sanity -> hub_descriptor_is_sane Changes in v6: more pedantic conversion from `int` to `bool`; fix comment Changes in v5: make `bool` a return type of `hub_check_descriptor_sanity()` Changes in v4: fix typo Changes in v3: extract the code to static function Changes in v2: fix spaces instead of tab, add missing 'Signed-off-by' drivers/usb/core/hub.c | 38 +++++++++++++++++++++----------------- 1 file changed, 21 insertions(+), 17 deletions(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index b8bb20d7acdb..0484cd348156 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -1661,10 +1661,28 @@ static void hub_disconnect(struct usb_interface *intf) kref_put(&hub->kref, hub_release); } +static bool hub_descriptor_is_sane(struct usb_host_interface *desc) +{ + /* Some hubs have a subclass of 1, which AFAICT according to the */ + /* specs is not defined, but it works */ + if (desc->desc.bInterfaceSubClass != 0 && + desc->desc.bInterfaceSubClass != 1) + return false; + + /* Multiple endpoints? What kind of mutant ninja-hub is this? */ + if (desc->desc.bNumEndpoints != 1) + return false; + + /* If the first endpoint is not interrupt IN, we'd better punt! */ + if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc)) + return false; + + return true; +} + static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct usb_host_interface *desc; - struct usb_endpoint_descriptor *endpoint; struct usb_device *hdev; struct usb_hub *hub; @@ -1739,25 +1757,11 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) } #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) && - (desc->desc.bInterfaceSubClass != 1)) { -descriptor_error: + if (!hub_descriptor_is_sane(desc)) { dev_err(&intf->dev, "bad descriptor, ignoring hub\n"); return -EIO; } - /* Multiple endpoints? What kind of mutant ninja-hub is this? */ - if (desc->desc.bNumEndpoints != 1) - goto descriptor_error; - - endpoint = &desc->endpoint[0].desc; - - /* If it's not an interrupt in endpoint, we'd better punt! */ - if (!usb_endpoint_is_int_in(endpoint)) - goto descriptor_error; - /* We found a hub */ dev_info(&intf->dev, "USB hub found\n"); @@ -1784,7 +1788,7 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND) hub->quirk_check_port_auto_suspend = 1; - if (hub_configure(hub, endpoint) >= 0) + if (hub_configure(hub, &desc->endpoint[0].desc) >= 0) return 0; hub_disconnect(intf); -- 2.13.1