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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 A1E87C43463 for ; Fri, 18 Sep 2020 03:00:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5696C23119 for ; Fri, 18 Sep 2020 03:00:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600398017; bh=qbSMNsJ2gHPCZ2bjnEYHCu6psAz7c1BEHIounyRdkQM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=HmgUgspOoaxuCfS5xd4ivv2vygz9l6G/FCOSkS9XAHLV9wA3v9N85LsK4aRlTcO11 YzYo2sSlOXezg7iinSCfvYmP00orkhSj81CGDUIwgLRfugAolJpeT3oLJIn4Ukk5b8 kNrJA+PZN//IBzC626X6ZmJzqmPF8GLDfZIZ/Xrk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730453AbgIRDAP (ORCPT ); Thu, 17 Sep 2020 23:00:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:53822 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727591AbgIRCFk (ORCPT ); Thu, 17 Sep 2020 22:05:40 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 20A2023718; Fri, 18 Sep 2020 02:05:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600394739; bh=qbSMNsJ2gHPCZ2bjnEYHCu6psAz7c1BEHIounyRdkQM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kIihJ/q6cQxj6qR/S4l9OBcFzgFs30eV47Xmn4puG9tUPXXcWjbFyxFQEkU/pZF+i Jcwyv5UKLHyBbVVWd7NP5Xvj899SKmpL3MZ2ik9Op6rrmofHzdi1XVoFjljqqDhNQk L+VyF3YKLOuZTRLRxMkz9LcOGM3HIVo13d6guQfI= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Andreas Steinmetz , Takashi Iwai , Sasha Levin , alsa-devel@alsa-project.org Subject: [PATCH AUTOSEL 5.4 220/330] ALSA: usb-audio: Fix case when USB MIDI interface has more than one extra endpoint descriptor Date: Thu, 17 Sep 2020 21:59:20 -0400 Message-Id: <20200918020110.2063155-220-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200918020110.2063155-1-sashal@kernel.org> References: <20200918020110.2063155-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 0cb4142b05f64..bc9068b616bb9 100644 --- a/sound/usb/midi.c +++ b/sound/usb/midi.c @@ -1827,6 +1827,28 @@ 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. */ @@ -1864,11 +1886,8 @@ 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