From patchwork Fri Oct 20 15:33:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hardik Gajjar X-Patchwork-Id: 13430903 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E00B1DDCB for ; Fri, 20 Oct 2023 15:33:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from hi1smtp01.de.adit-jv.com (smtp1.de.adit-jv.com [93.241.18.167]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 74721AB; Fri, 20 Oct 2023 08:33:43 -0700 (PDT) Received: from hi2exch02.adit-jv.com (hi2exch02.adit-jv.com [10.72.92.28]) by hi1smtp01.de.adit-jv.com (Postfix) with ESMTP id 86651520216; Fri, 20 Oct 2023 17:33:41 +0200 (CEST) Received: from vmlxhi-118.adit-jv.com (10.72.93.77) by hi2exch02.adit-jv.com (10.72.92.28) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.34; Fri, 20 Oct 2023 17:33:41 +0200 From: Hardik Gajjar To: , , CC: , , , Subject: [PATCH] usb: gadget: f_ncm: Always set current gadget in ncm_bind() Date: Fri, 20 Oct 2023 17:33:24 +0200 Message-ID: <20231020153324.82794-1-hgajjar@de.adit-jv.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Originating-IP: [10.72.93.77] X-ClientProxiedBy: hi2exch02.adit-jv.com (10.72.92.28) To hi2exch02.adit-jv.com (10.72.92.28) Previously, gadget assignment to the net device occurred exclusively during the initial binding attempt. Nevertheless, the gadget pointer could change during bind/unbind cycles due to various conditions, including the unloading/loading of the UDC device driver or the detachment/reconnection of an OTG-capable USB hub device. This patch relocates the gether_set_gadget() function out from ncm_opts->bound condition check, ensuring that the correct gadget is assigned during each bind request. The provided logs demonstrate the consistency of ncm_opts throughout the power cycle, while the gadget may change. * OTG hub connected during boot up and assignment of gadget and ncm_opts pointer [ 2.366301] usb 2-1.5: New USB device found, idVendor=2996, idProduct=0105 [ 2.366304] usb 2-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 2.366306] usb 2-1.5: Product: H2H Bridge [ 2.366308] usb 2-1.5: Manufacturer: Aptiv [ 2.366309] usb 2-1.5: SerialNumber: 13FEB2021 [ 2.427989] usb 2-1.5: New USB device found, VID=2996, PID=0105 [ 2.428959] dabridge 2-1.5:1.0: dabridge 2-4 total endpoints=5, 0000000093a8d681 [ 2.429710] dabridge 2-1.5:1.0: P(0105) D(22.06.22) F(17.3.16) H(1.1) high-speed [ 2.429714] dabridge 2-1.5:1.0: Hub 2-2 P(0151) V(06.87) [ 2.429956] dabridge 2-1.5:1.0: All downstream ports in host mode [ 2.430093] gadget 000000003c414d59 ------> gadget pointer * NCM opts and associated gadget pointer during First ncm_bind [ 34.763929] NCM opts 00000000aa304ac9 [ 34.763930] NCM gadget 000000003c414d59 * OTG capable hub disconnecte or assume driver unload. [ 97.203114] usb 2-1: USB disconnect, device number 2 [ 97.203118] usb 2-1.1: USB disconnect, device number 3 [ 97.209217] usb 2-1.5: USB disconnect, device number 4 [ 97.230990] dabr_udc deleted * Reconnect the OTG hub or load driver assaign new gadget pointer. [ 111.534035] usb 2-1.1: New USB device found, idVendor=2996, idProduct=0120, bcdDevice= 6.87 [ 111.534038] usb 2-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 111.534040] usb 2-1.1: Product: Vendor [ 111.534041] usb 2-1.1: Manufacturer: Aptiv [ 111.534042] usb 2-1.1: SerialNumber: Superior [ 111.535175] usb 2-1.1: New USB device found, VID=2996, PID=0120 [ 111.610995] usb 2-1.5: new high-speed USB device number 8 using xhci-hcd [ 111.630052] usb 2-1.5: New USB device found, idVendor=2996, idProduct=0105, bcdDevice=21.02 [ 111.630055] usb 2-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 111.630057] usb 2-1.5: Product: H2H Bridge [ 111.630058] usb 2-1.5: Manufacturer: Aptiv [ 111.630059] usb 2-1.5: SerialNumber: 13FEB2021 [ 111.687464] usb 2-1.5: New USB device found, VID=2996, PID=0105 [ 111.690375] dabridge 2-1.5:1.0: dabridge 2-8 total endpoints=5, 000000000d87c961 [ 111.691172] dabridge 2-1.5:1.0: P(0105) D(22.06.22) F(17.3.16) H(1.1) high-speed [ 111.691176] dabridge 2-1.5:1.0: Hub 2-6 P(0151) V(06.87) [ 111.691646] dabridge 2-1.5:1.0: All downstream ports in host mode [ 111.692298] gadget 00000000dc72f7a9 --------> new gadget ptr on connect * NCM opts and associated gadget pointer during second ncm_bind [ 113.271786] NCM opts 00000000aa304ac9 -----> same opts ptr used during first bind [ 113.271788] NCM gadget 00000000dc72f7a9 ----> however new gaget ptr, that will not set in net_device due to ncm_opts->bound = true Signed-off-by: Hardik Gajjar --- drivers/usb/gadget/function/f_ncm.c | 27 +++++++++++---------------- 1 file changed, 11 insertions(+), 16 deletions(-) diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c index 424bb3b666db..af95896cab00 100644 --- a/drivers/usb/gadget/function/f_ncm.c +++ b/drivers/usb/gadget/function/f_ncm.c @@ -1413,7 +1413,7 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f) struct usb_composite_dev *cdev = c->cdev; struct f_ncm *ncm = func_to_ncm(f); struct usb_string *us; - int status; + int status = 0; struct usb_ep *ep; struct f_ncm_opts *ncm_opts; @@ -1431,22 +1431,17 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f) f->os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc; } - /* - * in drivers/usb/gadget/configfs.c:configfs_composite_bind() - * configurations are bound in sequence with list_for_each_entry, - * in each configuration its functions are bound in sequence - * with list_for_each_entry, so we assume no race condition - * with regard to ncm_opts->bound access - */ - if (!ncm_opts->bound) { - mutex_lock(&ncm_opts->lock); - gether_set_gadget(ncm_opts->net, cdev->gadget); + mutex_lock(&ncm_opts->lock); + gether_set_gadget(ncm_opts->net, cdev->gadget); + if (!ncm_opts->bound) status = gether_register_netdev(ncm_opts->net); - mutex_unlock(&ncm_opts->lock); - if (status) - goto fail; - ncm_opts->bound = true; - } + mutex_unlock(&ncm_opts->lock); + + if (status) + goto fail; + + ncm_opts->bound = true; + us = usb_gstrings_attach(cdev, ncm_strings, ARRAY_SIZE(ncm_string_defs)); if (IS_ERR(us)) {