From patchwork Fri Mar 29 04:14:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Yu X-Patchwork-Id: 10876371 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BAB0314DE for ; Fri, 29 Mar 2019 04:15:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A589628617 for ; Fri, 29 Mar 2019 04:15:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9925228FC3; Fri, 29 Mar 2019 04:15:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 29C7028617 for ; Fri, 29 Mar 2019 04:15:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728678AbfC2EOi (ORCPT ); Fri, 29 Mar 2019 00:14:38 -0400 Received: from szxga07-in.huawei.com ([45.249.212.35]:48888 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728648AbfC2EOh (ORCPT ); Fri, 29 Mar 2019 00:14:37 -0400 Received: from DGGEMS411-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 245AD403303FE242CEBD; Fri, 29 Mar 2019 12:14:35 +0800 (CST) Received: from vm100-107-113-134.huawei.com (100.107.113.134) by DGGEMS411-HUB.china.huawei.com (10.3.19.211) with Microsoft SMTP Server id 14.3.408.0; Fri, 29 Mar 2019 12:14:24 +0800 From: Yu Chen To: , , CC: , , , , , , , , , , , , , , Yu Chen , "Greg Kroah-Hartman" , Heikki Krogerus , Hans de Goede , "Andy Shevchenko" Subject: [PATCH v5 09/13] usb: roles: Add usb role switch notifier. Date: Fri, 29 Mar 2019 12:14:05 +0800 Message-ID: <20190329041409.70138-10-chenyu56@huawei.com> X-Mailer: git-send-email 2.15.0-rc2 In-Reply-To: <20190329041409.70138-1-chenyu56@huawei.com> References: <20190329041409.70138-1-chenyu56@huawei.com> MIME-Version: 1.0 X-Originating-IP: [100.107.113.134] X-CFilter-Loop: Reflected Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds notifier for drivers want to be informed of the usb role switch. Cc: Greg Kroah-Hartman Cc: Heikki Krogerus Cc: Hans de Goede Cc: Andy Shevchenko Cc: John Stultz Suggested-by: Heikki Krogerus Signed-off-by: Yu Chen Reviewed-by: Heikki Krogerus --- v5: * Split the patch into two patches, the first one introduces stubs for the exiting functions, and this patch adds notifier functions. --- --- drivers/usb/roles/class.c | 20 +++++++++++++++++++- include/linux/usb/role.h | 16 ++++++++++++++++ 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c index f45d8df5cfb8..e2caaa665d6e 100644 --- a/drivers/usb/roles/class.c +++ b/drivers/usb/roles/class.c @@ -20,6 +20,7 @@ struct usb_role_switch { struct device dev; struct mutex lock; /* device lock*/ enum usb_role role; + struct blocking_notifier_head nh; /* From descriptor */ struct device *usb2_port; @@ -49,8 +50,10 @@ int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role) mutex_lock(&sw->lock); ret = sw->set(sw->dev.parent, role); - if (!ret) + if (!ret) { sw->role = role; + blocking_notifier_call_chain(&sw->nh, role, NULL); + } mutex_unlock(&sw->lock); @@ -58,6 +61,20 @@ int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role) } EXPORT_SYMBOL_GPL(usb_role_switch_set_role); +int usb_role_switch_register_notifier(struct usb_role_switch *sw, + struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&sw->nh, nb); +} +EXPORT_SYMBOL_GPL(usb_role_switch_register_notifier); + +int usb_role_switch_unregister_notifier(struct usb_role_switch *sw, + struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&sw->nh, nb); +} +EXPORT_SYMBOL_GPL(usb_role_switch_unregister_notifier); + /** * usb_role_switch_get_role - Get the USB role for a switch * @sw: USB role switch @@ -271,6 +288,7 @@ usb_role_switch_register(struct device *parent, return ERR_PTR(-ENOMEM); mutex_init(&sw->lock); + BLOCKING_INIT_NOTIFIER_HEAD(&sw->nh); sw->allow_userspace_control = desc->allow_userspace_control; sw->usb2_port = desc->usb2_port; diff --git a/include/linux/usb/role.h b/include/linux/usb/role.h index da2b9641b877..99d8b8e4fe61 100644 --- a/include/linux/usb/role.h +++ b/include/linux/usb/role.h @@ -53,6 +53,10 @@ struct usb_role_switch * usb_role_switch_register(struct device *parent, const struct usb_role_switch_desc *desc); void usb_role_switch_unregister(struct usb_role_switch *sw); +int usb_role_switch_register_notifier(struct usb_role_switch *sw, + struct notifier_block *nb); +int usb_role_switch_unregister_notifier(struct usb_role_switch *sw, + struct notifier_block *nb); #else static inline int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role) @@ -80,6 +84,18 @@ usb_role_switch_register(struct device *parent, } static inline void usb_role_switch_unregister(struct usb_role_switch *sw) { } + +static int usb_role_switch_register_notifier(struct usb_role_switch *sw, + struct notifier_block *nb) +{ + return -ENODEV; +} + +static int usb_role_switch_unregister_notifier(struct usb_role_switch *sw, + struct notifier_block *nb) +{ + return -ENODEV; +} #endif #endif /* __LINUX_USB_ROLE_H */