From patchwork Sat Mar 2 09:05:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Yu X-Patchwork-Id: 10836525 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 44D50139A for ; Sat, 2 Mar 2019 09:06:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 30BE12C486 for ; Sat, 2 Mar 2019 09:06:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 217F92C50A; Sat, 2 Mar 2019 09:06:31 +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 99D692C486 for ; Sat, 2 Mar 2019 09:06:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727854AbfCBJFl (ORCPT ); Sat, 2 Mar 2019 04:05:41 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:4196 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727721AbfCBJFk (ORCPT ); Sat, 2 Mar 2019 04:05:40 -0500 Received: from DGGEMS406-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id CC1CE67C0FBFF9400ED5; Sat, 2 Mar 2019 17:05:35 +0800 (CST) Received: from vm100-107-113-134.huawei.com (100.107.113.134) by DGGEMS406-HUB.china.huawei.com (10.3.19.206) with Microsoft SMTP Server id 14.3.408.0; Sat, 2 Mar 2019 17:05:29 +0800 From: Yu Chen To: , , CC: , , , , , , , , , , , , , , Yu Chen , "Greg Kroah-Hartman" , Heikki Krogerus , Hans de Goede , "Andy Shevchenko" Subject: [PATCH v3 08/12] usb: roles: Add usb role switch notifier. Date: Sat, 2 Mar 2019 17:05:01 +0800 Message-ID: <20190302090505.65542-9-chenyu56@huawei.com> X-Mailer: git-send-email 2.15.0-rc2 In-Reply-To: <20190302090505.65542-1-chenyu56@huawei.com> References: <20190302090505.65542-1-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 --- drivers/usb/roles/class.c | 20 +++++++++++++++++++- include/linux/usb/role.h | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 65 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 9684a8734757..9e1ca663387a 100644 --- a/include/linux/usb/role.h +++ b/include/linux/usb/role.h @@ -41,6 +41,8 @@ struct usb_role_switch_desc { bool allow_userspace_control; }; + +#if IS_ENABLED(CONFIG_USB_ROLE_SWITCH) int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role); enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw); struct usb_role_switch *usb_role_switch_get(struct device *dev); @@ -50,5 +52,49 @@ 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) +{ + return 0; +} + +static inline enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw) +{ + return USB_ROLE_NONE; +} + +static inline struct usb_role_switch *usb_role_switch_get(struct device *dev) +{ + return ERR_PTR(-ENODEV); +} + +static inline void usb_role_switch_put(struct usb_role_switch *sw) { } + +static inline struct usb_role_switch * +usb_role_switch_register(struct device *parent, + const struct usb_role_switch_desc *desc) +{ + return ERR_PTR(-ENODEV); +} + +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 */