From patchwork Wed May 31 04:02:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Badhri Jagan Sridharan X-Patchwork-Id: 13261410 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 119ADC77B73 for ; Wed, 31 May 2023 04:02:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234166AbjEaECY (ORCPT ); Wed, 31 May 2023 00:02:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53302 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234071AbjEaECP (ORCPT ); Wed, 31 May 2023 00:02:15 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E92C10E for ; Tue, 30 May 2023 21:02:11 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-565ba5667d5so87991227b3.0 for ; Tue, 30 May 2023 21:02:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1685505730; x=1688097730; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=pTATTkgvxztq9cna9gYn1cQG7KZBsx+3nMydlu+2mlE=; b=al+sJCyOmkaF/6ULIYjfy2VcVPz2C1bJQqcCbgFH/qdd7Y3x3ihhhi+6+rzdnEiUv8 lWpn7yW5seO+rgx/NlgTtfMTIYxkGcVq+TSRBWky9mfQUVCpRWY93+2uS5MuaL75iEDA JQ10HgpgPVDpe+CX3mqaEzbLU4+OSdpKbgU8DULnbEDbNMZ98Xg5KZYbWZrFG/RMGaGR jTnl1guy/5DX8hhiygVrhV049zJ1vcM2cd3XqRd4+0afw78MpemU5/cde1on4KzSuR9e ipRGINz/G0pNg9bKudvd2xs9iSVvrJ7sMHbVynO6oRjOrqbl9maLQHug6QJH1nM5+8b2 OqGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685505730; x=1688097730; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=pTATTkgvxztq9cna9gYn1cQG7KZBsx+3nMydlu+2mlE=; b=JhFILVPq7AFzqt7Um2ZWo27D+zSDml3E9hV3gp55xL0TFlt9wRKfQCcaEwaGQe6tkq Dl83QeHb7INYJdKV9L06xP9pNCV2dFukRtk/D39Q41+tLYSGxWDSD6T2HNgphyKslIsC +hucEq9EyzuRHkXMwWYBQMIGBnOzaTlKI5bdkMn3B3s0sZt2keCubMPSr305o+bIz8Z6 pkhS978xZpSuJzJlC8flcg1WJrKek+wcGoyqYZcFZ5H66kQry51Uhzi7KosxJhp2KcoP 81+duJDRcf8DWErd4+MJnXbNnhW+SuYTHihGPnOM/VOBxs7Olau8DLVNeGw4NsyqFA1W Izww== X-Gm-Message-State: AC+VfDxifDqm0ewVtkr6A7/IrIfpKXblgifJMrpHGR2+KIkpnVRurBq1 ownldY892OU88VEAUaLTD02FoUIXwtw= X-Google-Smtp-Source: ACHHUZ4p0nM25uD1L98TaYBOU36BLpBLGMgEtVGS7cVeo7z12dgaiYwxkeFtmy9TSgo24jh7ThbNKIabBSM= X-Received: from badhri.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:6442]) (user=badhri job=sendgmr) by 2002:a81:b661:0:b0:565:ce25:2693 with SMTP id h33-20020a81b661000000b00565ce252693mr2529499ywk.3.1685505730774; Tue, 30 May 2023 21:02:10 -0700 (PDT) Date: Wed, 31 May 2023 04:02:03 +0000 In-Reply-To: <20230531040203.19295-1-badhri@google.com> Mime-Version: 1.0 References: <20230531040203.19295-1-badhri@google.com> X-Mailer: git-send-email 2.41.0.rc0.172.g3f132b7071-goog Message-ID: <20230531040203.19295-3-badhri@google.com> Subject: [PATCH v5 3/3] usb: gadget: udc: core: Prevent UDC from starting when unbound From: Badhri Jagan Sridharan To: gregkh@linuxfoundation.org, stern@rowland.harvard.edu, colin.i.king@gmail.com, xuetao09@huawei.com, quic_eserrao@quicinc.com, water.zhangjiantao@huawei.com, peter.chen@freescale.com, balbi@ti.com, francesco@dolcini.it, alistair@alistair23.me, stephan@gerhold.net, bagasdotme@gmail.com, luca@z3ntu.xyz Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Badhri Jagan Sridharan , stable Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org UDC should neither be started nor pulled up unless the gadget driver is bound. The new flag "allow_start" is now set by gadget_bind_driver() and cleared by gadget_unbind_driver(). usb_gadget_udc_start_locked() now checks whether allow_start is set before starting the UDC by invoking the ->udc_start() callback. Fixes: fc274c1e9973 ("USB: gadget: Add a new bus for gadgets") Cc: stable Signed-off-by: Badhri Jagan Sridharan --- v5 is the first version in this series. --- drivers/usb/gadget/udc/core.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index 6ffe5fda8bb7..ac9d6186815d 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -37,6 +37,8 @@ static const struct bus_type gadget_bus_type; * @vbus: for udcs who care about vbus status, this value is real vbus status; * for udcs who do not care about vbus status, this value is always true * @started: the UDC's started state. True if the UDC had started. + * @allow_start: Indicates whether UDC is allowed to start. Set/cleared by gadget_(un)bind_driver() + * after gadget driver is bound or unbound. * @connect_lock: protects udc->vbus, udc->started, gadget->connect, gadget->deactivate related * functions. usb_gadget_connect_locked, usb_gadget_disconnect_locked, * usb_udc_connect_control_locked, usb_gadget_udc_start_locked, usb_gadget_udc_stop_locked are @@ -52,6 +54,7 @@ struct usb_udc { struct list_head list; bool vbus; bool started; + bool allow_start; struct work_struct vbus_work; struct mutex connect_lock; }; @@ -1204,6 +1207,9 @@ static inline int usb_gadget_udc_start_locked(struct usb_udc *udc) if (udc->started) { dev_err(&udc->dev, "UDC had already started\n"); return -EBUSY; + } else if (!udc->allow_start) { + dev_err(&udc->dev, "UDC not allowed to start. Is gadget driver bound ?\n"); + return -EIO; } ret = udc->gadget->ops->udc_start(udc->gadget, udc->driver); @@ -1590,6 +1596,7 @@ static int gadget_bind_driver(struct device *dev) goto err_bind; mutex_lock(&udc->connect_lock); + udc->allow_start = true; ret = usb_gadget_udc_start_locked(udc); if (ret) { mutex_unlock(&udc->connect_lock); @@ -1630,6 +1637,7 @@ static void gadget_unbind_driver(struct device *dev) cancel_work_sync(&udc->vbus_work); mutex_lock(&udc->connect_lock); + udc->allow_start = false; usb_gadget_disconnect_locked(gadget); usb_gadget_disable_async_callbacks(udc); if (gadget->irq)