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 alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4270DC7618E for ; Mon, 24 Apr 2023 10:34:32 +0000 (UTC) Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 3E01FF28; Mon, 24 Apr 2023 12:33:40 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 3E01FF28 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1682332470; bh=I+AArAY1YcEyPrvgN7assWYGYocSeYaZq0COT2cIpEI=; h=Date:From:To:Subject:References:In-Reply-To:CC:List-Id: List-Archive:List-Help:List-Owner:List-Post:List-Subscribe: List-Unsubscribe:From; b=BaemJR2AsQF0ct2MIRlTZd4jYtBplEM796JD+KFV19m5ays1yt657ZhIgjEOo0oaZ 8d9axiMZ5YFNVWmTY1uezItdOxb0jkMWIyako7xODIiH33BxZ/m17C8WjMAJIFp+Ro qv7frRjGaMyVCu9rQ8nhxnT6zhjwdAMxRsosR7qk= Received: from mailman-core.alsa-project.org (mailman-core.alsa-project.org [10.254.200.10]) by alsa1.perex.cz (Postfix) with ESMTP id D5F26F8018A; Mon, 24 Apr 2023 12:33:14 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id A9728F8018A; Mon, 24 Apr 2023 12:33:08 +0200 (CEST) Received: from bluemchen.kde.org (bluemchen.kde.org [209.51.188.41]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id C9EFCF80104 for ; Mon, 24 Apr 2023 12:33:00 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz C9EFCF80104 Received: from ugly.fritz.box (localhost [127.0.0.1]) by bluemchen.kde.org (Postfix) with ESMTP id B9E4523E69; Mon, 24 Apr 2023 06:32:58 -0400 (EDT) Received: by ugly.fritz.box (masqmail 0.3.4, from userid 1000) id 1pqtVC-MLH-00; Mon, 24 Apr 2023 12:32:58 +0200 Date: Mon, 24 Apr 2023 12:32:58 +0200 From: Oswald Buddenhagen To: Takashi Iwai Subject: Re: [PATCH] ALSA: emu10k1: fix multi-channel playback device class Message-ID: Mail-Followup-To: Takashi Iwai , alsa-devel@alsa-project.org, Jaroslav Kysela References: <20230422161021.1143989-1-oswald.buddenhagen@gmx.de> <874jp7oy2k.wl-tiwai@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <874jp7oy2k.wl-tiwai@suse.de> Message-ID-Hash: JKYQETHXQ6NA7JFQPK2JOE7F77JKGINC X-Message-ID-Hash: JKYQETHXQ6NA7JFQPK2JOE7F77JKGINC X-MailFrom: ossi@kde.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-alsa-devel.alsa-project.org-0; header-match-alsa-devel.alsa-project.org-1; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: alsa-devel@alsa-project.org X-Mailman-Version: 3.3.8 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Sun, Apr 23, 2023 at 09:30:11AM +0200, Takashi Iwai wrote: >On Sat, 22 Apr 2023 18:10:21 +0200, >Oswald Buddenhagen wrote: >> >> It's multi, not mono/stereo. >> >> AFAICT, this doesn't do anything in the kernel. > >... but those values are read by user-space. > >> Also, I think the subclass is meaningless for devices with just one >> stream, but whatever. > >Again, the value is read by user-space. > i assumed that much. but these are another thing that appears to have exactly zero useful documentation. >So changing both have clear influence on the user-space program, and >unless you have to change this for fixing a real bug (and there is no >other way), this is too risky. IOW, too late to change, we have to >accept those values. > there aren't any precedents for use of SNDRV_PCM_CLASS_MULTI and SNDRV_PCM_SUBCLASS_MULTI_MIX in the kernel tree. there don't appear to be relevant hits outside the kernel, either. it's conceivable that some code would check for the *_GENERIC enums, but i didn't find such code. so i'd postulate that these enums are effectively dead, and both the risk and the gain of this change are about zero. i suggest to initiate a formal deprecation procedure for the MULTI enum values, however that's supposed to look like. regards