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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84863C7EE2F for ; Wed, 7 Jun 2023 13:35:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240809AbjFGNfl (ORCPT ); Wed, 7 Jun 2023 09:35:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54802 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239276AbjFGNfh (ORCPT ); Wed, 7 Jun 2023 09:35:37 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 497BB1BF0; Wed, 7 Jun 2023 06:35:27 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id EC54C1FDAA; Wed, 7 Jun 2023 13:35:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1686144925; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=BYiTeYmwLMBlpKvFU+nNSlpL2e+cOtcyKH6DxhJ12bE=; b=oTdZBSxnsMNNnKsTVUYGnj1R+CFFp6oJFX1LZD2LOn7NxJ03J2hx5m06KB3yhl+47oM4Qk 3rC1hqbqThHZv3AcZqsAHFUwGRDnCgp3zcvtNlk1Uez3IlfPt65ZKOs2hp0831I2xcFGgx hhqvJ4HnuUT+kLiXAOlzfih0pUm8pRg= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1686144925; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=BYiTeYmwLMBlpKvFU+nNSlpL2e+cOtcyKH6DxhJ12bE=; b=jkIjQP+4LWHQuK8dPKrwoIRgYghRjTfYsAXtJBvC5sFDLFGG80lhe7Rs3ilL2p+G8p8VG9 zFIyAPWuoplKj4Aw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id C97E81346D; Wed, 7 Jun 2023 13:35:25 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id i5G+MJ2HgGQSbQAAMHmgww (envelope-from ); Wed, 07 Jun 2023 13:35:25 +0000 Date: Wed, 07 Jun 2023 15:35:25 +0200 Message-ID: <87ilbzgztu.wl-tiwai@suse.de> From: Takashi Iwai To: Ivan Orlov Cc: perex@perex.cz, tiwai@suse.com, corbet@lwn.net, broonie@kernel.org, skhan@linuxfoundation.org, alsa-devel@alsa-project.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, gregkh@linuxfoundation.org, himadrispandya@gmail.com, linux-kernel-mentees@lists.linuxfoundation.org Subject: Re: [PATCH v4 1/3] docs: sound: add 'pcmtest' driver documentation In-Reply-To: <20230606193254.20791-1-ivan.orlov0322@gmail.com> References: <20230606193254.20791-1-ivan.orlov0322@gmail.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/27.2 Mule/6.0 MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Tue, 06 Jun 2023 21:32:52 +0200, Ivan Orlov wrote: > > Add documentation for the new Virtual PCM Test Driver. It covers all > possible usage cases: errors and delay injections, random and > pattern-based data generation, playback and ioctl redefinition > functionalities testing. > > We have a lot of different virtual media drivers, which can be used for > testing of the userspace applications and media subsystem middle layer. > However, all of them are aimed at testing the video functionality and > simulating the video devices. For audio devices we have only snd-dummy > module, which is good in simulating the correct behavior of an ALSA device. > I decided to write a tool, which would help to test the userspace ALSA > programs (and the PCM middle layer as well) under unusual circumstances > to figure out how they would behave. So I came up with this Virtual PCM > Test Driver. > > This new Virtual PCM Test Driver has several features which can be useful > during the userspace ALSA applications testing/fuzzing, or testing/fuzzing > of the PCM middle layer. Not all of them can be implemented using the > existing virtual drivers (like dummy or loopback). Here is what can this > driver do: > > - Simulate both capture and playback processes > - Check the playback stream for containing the looped pattern > - Generate random or pattern-based capture data > - Inject delays into the playback and capturing processes > - Inject errors during the PCM callbacks > > Also, this driver can check the playback stream for containing the > predefined pattern, which is used in the corresponding selftest to check > the PCM middle layer data transferring functionality. Additionally, this > driver redefines the default RESET ioctl, and the selftest covers this PCM > API functionality as well. > > The driver supports both interleaved and non-interleaved access modes, and > have separate pattern buffers for each channel. The driver supports up to > 4 channels and up to 8 substreams. > > Signed-off-by: Ivan Orlov Now I merged all three patches. thanks, Takashi