From patchwork Thu Mar 2 10:55:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bastien Nocera X-Patchwork-Id: 658306 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54678C678D4 for ; Thu, 2 Mar 2023 10:56:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229868AbjCBK4L (ORCPT ); Thu, 2 Mar 2023 05:56:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229652AbjCBK4J (ORCPT ); Thu, 2 Mar 2023 05:56:09 -0500 Received: from relay3-d.mail.gandi.net (relay3-d.mail.gandi.net [217.70.183.195]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A441943900; Thu, 2 Mar 2023 02:56:07 -0800 (PST) Received: (Authenticated sender: hadess@hadess.net) by mail.gandi.net (Postfix) with ESMTPSA id DCDBE60008; Thu, 2 Mar 2023 10:56:04 +0000 (UTC) From: Bastien Nocera To: linux-usb@vger.kernel.org, linux-input@vger.kernel.org Cc: Greg Kroah-Hartman , Alan Stern , Benjamin Tissoires , =?utf-8?q?Filipe_La?= =?utf-8?q?=C3=ADns?= , Nestor Lopez Casado Subject: [PATCH v3 5/6] USB: core: Add API to change the wireless_status Date: Thu, 2 Mar 2023 11:55:54 +0100 Message-Id: <20230302105555.51417-5-hadess@hadess.net> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230302105555.51417-1-hadess@hadess.net> References: <20230302105555.51417-1-hadess@hadess.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org This adds the API that allows device specific drivers to tell user-space about whether the wireless device is connected to its receiver dongle. See "USB: core: Add wireless_status sysfs attribute" for a detailed explanation of what this attribute should be used for. Signed-off-by: Bastien Nocera Acked-by: Greg Kroah-Hartman --- Fixed locking/use-after-free in v2, thanks to Alan Stern Fixed ordering of locking/put in v3, thanks to Alan Stern again drivers/usb/core/message.c | 40 ++++++++++++++++++++++++++++++++++++++ include/linux/usb.h | 5 +++++ 2 files changed, 45 insertions(+) diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 127fac1af676..7930dca84616 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -1908,6 +1908,45 @@ static void __usb_queue_reset_device(struct work_struct *ws) usb_put_intf(iface); /* Undo _get_ in usb_queue_reset_device() */ } +/* + * Internal function to set the wireless_status sysfs attribute + * See usb_set_wireless_status() for more details + */ +static void __usb_wireless_status_intf(struct work_struct *ws) +{ + struct usb_interface *iface = + container_of(ws, struct usb_interface, wireless_status_work); + + device_lock(iface->dev.parent); + if (iface->sysfs_files_created) + usb_update_wireless_status_attr(iface); + device_unlock(iface->dev.parent); + usb_put_intf(iface); /* Undo _get_ in usb_set_wireless_status() */ +} + +/** + * usb_set_wireless_status - sets the wireless_status struct member + * @dev: the device to modify + * @status: the new wireless status + * + * Set the wireless_status struct member to the new value, and emit + * sysfs changes as necessary. + * + * Returns: 0 on success, -EALREADY if already set. + */ +int usb_set_wireless_status(struct usb_interface *iface, + enum usb_wireless_status status) +{ + if (iface->wireless_status == status) + return -EALREADY; + + usb_get_intf(iface); + iface->wireless_status = status; + schedule_work(&iface->wireless_status_work); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_set_wireless_status); /* * usb_set_configuration - Makes a particular device setting be current @@ -2100,6 +2139,7 @@ int usb_set_configuration(struct usb_device *dev, int configuration) intf->dev.type = &usb_if_device_type; intf->dev.groups = usb_interface_groups; INIT_WORK(&intf->reset_ws, __usb_queue_reset_device); + INIT_WORK(&intf->wireless_status_work, __usb_wireless_status_intf); intf->minor = -1; device_initialize(&intf->dev); pm_runtime_no_callbacks(&intf->dev); diff --git a/include/linux/usb.h b/include/linux/usb.h index 46fc85aba0df..a48eeec62a66 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -262,6 +262,7 @@ struct usb_interface { unsigned resetting_device:1; /* true: bandwidth alloc after reset */ unsigned authorized:1; /* used for interface authorization */ enum usb_wireless_status wireless_status; + struct work_struct wireless_status_work; struct device dev; /* interface specific device info */ struct device *usb_dev; @@ -896,6 +897,10 @@ static inline int usb_interface_claimed(struct usb_interface *iface) extern void usb_driver_release_interface(struct usb_driver *driver, struct usb_interface *iface); + +int usb_set_wireless_status(struct usb_interface *iface, + enum usb_wireless_status status); + const struct usb_device_id *usb_match_id(struct usb_interface *interface, const struct usb_device_id *id); extern int usb_match_one_id(struct usb_interface *interface,