From patchwork Tue Sep 29 10:59:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 263305 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 3694CC4727C for ; Tue, 29 Sep 2020 11:34:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E08DC23F2A for ; Tue, 29 Sep 2020 11:34:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601379288; bh=ZOdhtg283gl1Kqzsq95npru5wbrb0UGgTLxBg0NezjI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SwWsoygOdO7vPeBUwR88pu8scCqwJPyPV9pxslPz7kqYSFl37b/5vAoKMDhCh/SFQ UDfGXK/OTCwxvM2BBlEgPdwTs0rdCsuvXBine3SuNfdqXa5NHsbr1UNX32ck9DC3oG oi1zDeDNk6wQeMZlhOQ8Q8Ny8MLgnbZjh1+/TSsQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728594AbgI2Les (ORCPT ); Tue, 29 Sep 2020 07:34:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:49134 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729584AbgI2Ld0 (ORCPT ); Tue, 29 Sep 2020 07:33:26 -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 A9FCB23B6C; Tue, 29 Sep 2020 11:26:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601378781; bh=ZOdhtg283gl1Kqzsq95npru5wbrb0UGgTLxBg0NezjI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VR93ap6VuNXcR7DaKuMA/VYYjKpkEneht1jRO40ZC5+2A/bS0ks9+abQRoSpuQCs3 eaYJyEM5uBXG9CvmK0790mTIBVGmd99BdLjeBFvcUtxEZuh1tfpOUmZ3r2L0KXrMI5 8vXU1922Wce+E7XcXTLNTq3FvnET4btFem1i225I= 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 4.19 135/245] ALSA: usb-audio: Fix case when USB MIDI interface has more than one extra endpoint descriptor Date: Tue, 29 Sep 2020 12:59:46 +0200 Message-Id: <20200929105953.557663538@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929105946.978650816@linuxfoundation.org> References: <20200929105946.978650816@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 28a3ad8b1d74b..137e1e8718d6f 100644 --- a/sound/usb/midi.c +++ b/sound/usb/midi.c @@ -1828,6 +1828,28 @@ 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. */ @@ -1865,11 +1887,8 @@ 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) {