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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 181E8C43441 for ; Sun, 11 Nov 2018 20:00:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D8BE120871 for ; Sun, 11 Nov 2018 20:00:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D8BE120871 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731030AbeKLFuD (ORCPT ); Mon, 12 Nov 2018 00:50:03 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:51226 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730746AbeKLFsd (ORCPT ); Mon, 12 Nov 2018 00:48:33 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gLvsq-0000tu-L4; Sun, 11 Nov 2018 19:59:00 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gLvsX-0001k6-0x; Sun, 11 Nov 2018 19:58:41 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Joshua Frkuska" , "Felipe Balbi" , "Eugeniu Rosca" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 264/366] usb: gadget: u_audio: update hw_ptr in iso_complete after data copied In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Joshua Frkuska commit 6b37bd78d30c890e575a1bda22978d1d2a233362 upstream. In u_audio_iso_complete, the runtime hw_ptr is updated before the data is actually copied over to/from the buffer/dma area. When ALSA uses this hw_ptr, the data may not actually be available to be used. This causes trash/stale audio to play/record. This patch updates the hw_ptr after the data has been copied to avoid this. Fixes: 132fcb460839 ("usb: gadget: Add Audio Class 2.0 Driver") Signed-off-by: Joshua Frkuska Signed-off-by: Eugeniu Rosca Signed-off-by: Felipe Balbi [bwh: Backported to 3.16: - Don't use a local hw_ptr variable - Adjust filename] Signed-off-by: Ben Hutchings --- --- a/drivers/usb/gadget/f_uac2.c +++ b/drivers/usb/gadget/f_uac2.c @@ -229,12 +229,16 @@ agdev_iso_complete(struct usb_ep *ep, st if (pending >= prm->period_size) update_alsa = true; - prm->hw_ptr = (prm->hw_ptr + req->actual) % prm->dma_bytes; - spin_unlock_irqrestore(&prm->lock, flags); /* Pack USB load in ALSA ring buffer */ memcpy(dst, src, req->actual); + + spin_lock_irqsave(&prm->lock, flags); + /* update hw_ptr after data is copied to memory */ + prm->hw_ptr = (prm->hw_ptr + req->actual) % prm->dma_bytes; + spin_unlock_irqrestore(&prm->lock, flags); + exit: if (usb_ep_queue(ep, req, GFP_ATOMIC)) dev_err(&uac2->pdev.dev, "%d Error!\n", __LINE__);