From patchwork Mon Mar 15 13:55:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 401395 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 487C8C4332B for ; Mon, 15 Mar 2021 14:03:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 24B68600EF for ; Mon, 15 Mar 2021 14:03:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233600AbhCOOCJ (ORCPT ); Mon, 15 Mar 2021 10:02:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:37632 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232834AbhCOOAB (ORCPT ); Mon, 15 Mar 2021 10:00:01 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9EFA764F31; Mon, 15 Mar 2021 13:59:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1615816781; bh=rmC7IlEqG/sf97jfBeF9COqnucpg5NZszwxabt3aGbU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KqLyLFHNv+0DF8B6NiIRfEkg69Ha5xvGF+iSrXaEVfSLvhfSfvN0Uuj5WyNMbQD9e ARJuiuWaiFjOTjy2fcni8fvpVjuizOtFrEzDcoxEckDZ5PYB5jauLujVDb7w/SC8Kk OGdhpp5NsyvjCAZ44PvXtyy163kX5uualtKiVyGg= From: gregkh@linuxfoundation.org To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Peter Chen , Ruslan Bilovol Subject: [PATCH 5.4 105/168] usb: gadget: f_uac2: always increase endpoint max_packet_size by one audio slot Date: Mon, 15 Mar 2021 14:55:37 +0100 Message-Id: <20210315135553.817987765@linuxfoundation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210315135550.333963635@linuxfoundation.org> References: <20210315135550.333963635@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Greg Kroah-Hartman From: Ruslan Bilovol commit 789ea77310f0200c84002884ffd628e2baf3ad8a upstream. As per UAC2 Audio Data Formats spec (2.3.1.1 USB Packets), if the sampling rate is a constant, the allowable variation of number of audio slots per virtual frame is +/- 1 audio slot. It means that endpoint should be able to accept/send +1 audio slot. Previous endpoint max_packet_size calculation code was adding sometimes +1 audio slot due to DIV_ROUND_UP behaviour which was rounding up to closest integer. However this doesn't work if the numbers are divisible. It had no any impact with Linux hosts which ignore this issue, but in case of more strict Windows it caused rejected enumeration Thus always add +1 audio slot to endpoint's max packet size Fixes: 913e4a90b6f9 ("usb: gadget: f_uac2: finalize wMaxPacketSize according to bandwidth") Cc: Peter Chen Cc: #v4.3+ Signed-off-by: Ruslan Bilovol Link: https://lore.kernel.org/r/1614599375-8803-2-git-send-email-ruslan.bilovol@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_uac2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/gadget/function/f_uac2.c +++ b/drivers/usb/gadget/function/f_uac2.c @@ -478,7 +478,7 @@ static int set_ep_max_packet_size(const } max_size_bw = num_channels(chmask) * ssize * - DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1))); + ((srate / (factor / (1 << (ep_desc->bInterval - 1)))) + 1); ep_desc->wMaxPacketSize = cpu_to_le16(min_t(u16, max_size_bw, max_size_ep));