From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C2688C4727C for ; Tue, 29 Sep 2020 11:04:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 76DC321941 for ; Tue, 29 Sep 2020 11:04:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601377480; bh=5oJXERcogd7RSgtOBW51ypRk6CSY3vCWQB6geNwizwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2SCdBCC8owezsw7OUbCjt0xJ820KU107nMVlUMIroTuds8r2itz0OgNII0rzPIMs0 Rwwzy1oQKwUkVWbAu/jlp4/mMF5g6nQL95ks5BgL3H+zLJKRhznqwmpsBC+qykmN7h HhYmMf64BDYSZfcmF7Z402o/Xjtnsns8BJ/8da9Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728646AbgI2LEj (ORCPT ); Tue, 29 Sep 2020 07:04:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:40760 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728627AbgI2LEe (ORCPT ); Tue, 29 Sep 2020 07:04:34 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6636921D43; Tue, 29 Sep 2020 11:04:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601377474; bh=5oJXERcogd7RSgtOBW51ypRk6CSY3vCWQB6geNwizwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xeSGZ0QLbeXgMmuSU0l0Gx+rJ3bc1hRqfPM4iknIHboGSvTBrzapmC9blZr2XGMNB /MXdDCVRd+7b5I/A7+QTCpduT7FDtyHNmdfkocNrKAYsUi8gPCylfXnhjh0dYVtYer XnWrLNVvTe3YGXCSH8PeZw0jnC4bgQqRVMb0IboI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andreas Steinmetz , Takashi Iwai , Sasha Levin Subject: [PATCH 4.4 48/85] ALSA: usb-audio: Fix case when USB MIDI interface has more than one extra endpoint descriptor Date: Tue, 29 Sep 2020 13:00:15 +0200 Message-Id: <20200929105930.637779107@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929105928.198942536@linuxfoundation.org> References: <20200929105928.198942536@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andreas Steinmetz [ Upstream commit 5c6cd7021a05a02fcf37f360592d7c18d4d807fb ] The Miditech MIDIFACE 16x16 (USB ID 1290:1749) has more than one extra endpoint descriptor. The first extra descriptor is: 0x06 0x30 0x00 0x00 0x00 0x00 As the code in snd_usbmidi_get_ms_info() looks only at the first extra descriptor to find USB_DT_CS_ENDPOINT the device as such is recognized but there is neither input nor output configured. The patch iterates through the extra descriptors to find the proper one. With this patch the device is correctly configured. Signed-off-by: Andreas Steinmetz Link: https://lore.kernel.org/r/1c3b431a86f69e1d60745b6110cdb93c299f120b.camel@domdv.de Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/usb/midi.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/sound/usb/midi.c b/sound/usb/midi.c index 5c4a3d6c42341..934540042bc2e 100644 --- a/sound/usb/midi.c +++ b/sound/usb/midi.c @@ -1803,6 +1803,28 @@ static int snd_usbmidi_create_endpoints(struct snd_usb_midi *umidi, return 0; } +static struct usb_ms_endpoint_descriptor *find_usb_ms_endpoint_descriptor( + struct usb_host_endpoint *hostep) +{ + unsigned char *extra = hostep->extra; + int extralen = hostep->extralen; + + while (extralen > 3) { + struct usb_ms_endpoint_descriptor *ms_ep = + (struct usb_ms_endpoint_descriptor *)extra; + + if (ms_ep->bLength > 3 && + ms_ep->bDescriptorType == USB_DT_CS_ENDPOINT && + ms_ep->bDescriptorSubtype == UAC_MS_GENERAL) + return ms_ep; + if (!extra[0]) + break; + extralen -= extra[0]; + extra += extra[0]; + } + return NULL; +} + /* * Returns MIDIStreaming device capabilities. */ @@ -1840,11 +1862,8 @@ static int snd_usbmidi_get_ms_info(struct snd_usb_midi *umidi, ep = get_ep_desc(hostep); if (!usb_endpoint_xfer_bulk(ep) && !usb_endpoint_xfer_int(ep)) continue; - ms_ep = (struct usb_ms_endpoint_descriptor *)hostep->extra; - if (hostep->extralen < 4 || - ms_ep->bLength < 4 || - ms_ep->bDescriptorType != USB_DT_CS_ENDPOINT || - ms_ep->bDescriptorSubtype != UAC_MS_GENERAL) + ms_ep = find_usb_ms_endpoint_descriptor(hostep); + if (!ms_ep) continue; if (usb_endpoint_dir_out(ep)) { if (endpoints[epidx].out_ep) { -- 2.25.1