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 BA996C19F28 for ; Wed, 3 Aug 2022 11:30:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236355AbiHCLaQ (ORCPT ); Wed, 3 Aug 2022 07:30:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49826 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233781AbiHCLaM (ORCPT ); Wed, 3 Aug 2022 07:30:12 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E9E5E42 for ; Wed, 3 Aug 2022 04:30:11 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E070761073 for ; Wed, 3 Aug 2022 11:30:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9A78C433C1; Wed, 3 Aug 2022 11:30:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1659526210; bh=gatN8ijDZVwF4fArqbchwbk0TWiuIZ1lb2Y6a4di8rU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ORM3M12TTZUk1D4DeCm0153pl+Tb2qLL5glZWRFYUkVeuqvRPzLhJ5pEEIpmwOXMC LfjbAwheH/SHSdv17EE1LxCNHJOmjuA+7n8BUf/eU8mFH/PVkV2wZ0YWtFov9RLkDe ddoS3wBZNRvp+mb/ykUMOiDlja2wPAdHzY4f6l8Pi++kyE8zec6c2H9WoY0oo6Xd8A 2Q2ElGtJzfZt2Zb2sVEM3EToCwXfWhK6bQO2fnLJDRfH9amKhz2tlRLLyaUxa1BEEo XjKc6oiwrm9Vtklp1xMOA87mH9RXau2ghOmghoYaTkgapUXug3GDN6Ke6NJhw1F5jw fPjPYgQ0L0Anw== Date: Wed, 3 Aug 2022 17:00:04 +0530 From: Vinod Koul To: Greg Kroah-Hartman Cc: Pierre-Louis Bossart , alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, Sanyog Kale , Bard Liao Subject: Re: [PATCH 2/5] soundwire: sysfs: cleanup the logic for creating the dp0 sysfs attributes Message-ID: References: <20220729135041.2285908-1-gregkh@linuxfoundation.org> <20220729135041.2285908-2-gregkh@linuxfoundation.org> <9365e038-2146-98f8-f989-02827f221c34@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 29-07-22, 17:03, Greg Kroah-Hartman wrote: > On Fri, Jul 29, 2022 at 09:57:52AM -0500, Pierre-Louis Bossart wrote: > > > > > > On 7/29/22 09:52, Greg Kroah-Hartman wrote: > > > On Fri, Jul 29, 2022 at 09:46:26AM -0500, Pierre-Louis Bossart wrote: > > >> > > >> > > >> On 7/29/22 08:50, Greg Kroah-Hartman wrote: > > >>> There's no need to special-case the dp0 sysfs attributes, the > > >>> is_visible() callback in the attribute group can handle that for us, so > > >>> add that and add it to the attribute group list making the logic simpler > > >>> overall. > > >>> > > >>> This is a step on the way to moving all of the sysfs attribute handling > > >>> into the default driver core attribute group logic so that the soundwire > > >>> core does not have to do any of it manually. > > >>> > > >>> Cc: Vinod Koul > > >>> Cc: Bard Liao > > >>> Cc: Pierre-Louis Bossart > > >>> Cc: Sanyog Kale > > >>> Cc: alsa-devel@alsa-project.org > > >>> Cc: linux-kernel@vger.kernel.org > > >>> Signed-off-by: Greg Kroah-Hartman > > >>> --- > > >>> drivers/soundwire/sysfs_slave.c | 18 ++++++++++++------ > > >>> 1 file changed, 12 insertions(+), 6 deletions(-) > > >>> > > >>> diff --git a/drivers/soundwire/sysfs_slave.c b/drivers/soundwire/sysfs_slave.c > > >>> index 83e3f6cc3250..3723333a5c2b 100644 > > >>> --- a/drivers/soundwire/sysfs_slave.c > > >>> +++ b/drivers/soundwire/sysfs_slave.c > > >>> @@ -174,6 +174,16 @@ static ssize_t words_show(struct device *dev, > > >>> } > > >>> static DEVICE_ATTR_RO(words); > > >>> > > >>> +static umode_t dp0_is_visible(struct kobject *kobj, struct attribute *attr, > > >>> + int n) > > >>> +{ > > >>> + struct sdw_slave *slave = dev_to_sdw_dev(kobj_to_dev(kobj)); > > >>> + > > >>> + if (slave->prop.dp0_prop) > > >>> + return attr->mode; > > >>> + return 0; > > >>> +} > > >> > > >> This changes the results slightly by creating an empty 'dp0' directory > > >> with no attributes inside. > > >> > > >> Before: > > >> > > >> [root@fedora ~]# cd /sys/bus/soundwire/devices/sdw:3:025d:0714:01 > > >> [root@fedora sdw:3:025d:0714:01]# ls dp0 > > >> ls: cannot access 'dp0': No such file or directory > > >> > > >> After: > > >> [root@fedora sdw:3:025d:0714:01]# ls dp0 > > > > > > That should be fine, tools should just be looking for the attributes, > > > not the existance of a directory, right? > > > > The idea what that we would only expose ports that actually exist. > > That's helpful information anyone with a basic knowledge of the > > SoundWire specification would understand. > > Is "dp0" a port? If so, why isn't it a real device? No they are not. It is a logical channel to send data to the device. The device can have one or many data ports... So the device logic or usb-endpoint style maynot look good here... The change looks good though, dp0 maybe present and empty, we should looks for attributes... > > The attributes are really details that few people/applications would > > understand, and unfortunately the information reported in DSDT is more > > often than not complete garbage. > > I don't understand what DSDT is, or how it is relevant here :( > > thanks, > > greg k-h -- ~Vinod