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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 36D4EC4360C for ; Sun, 6 Oct 2019 11:05:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0A36A2084D for ; Sun, 6 Oct 2019 11:04:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726377AbfJFLE7 (ORCPT ); Sun, 6 Oct 2019 07:04:59 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:43634 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726224AbfJFLE6 (ORCPT ); Sun, 6 Oct 2019 07:04:58 -0400 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 512) id 9D38780476; Sun, 6 Oct 2019 13:04:41 +0200 (CEST) Date: Sun, 6 Oct 2019 13:04:56 +0200 From: Pavel Machek To: Daniel Thompson , alex@alexanderweb.de, andriy.shevchenko@linux.intel.com Cc: Jani Nikula , Jonathan Corbet , Mat King , rafael@kernel.org, gregkh@linuxfoundation.org, Ross Zwisler , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Jingoo Han , Rajat Jain , Lee Jones , Alexander Schremmer , Andy Shevchenko Subject: Re: New sysfs interface for privacy screens Message-ID: <20191006110455.GC24605@amd> References: <20191002094650.3fc06a85@lwn.net> <87muei9r7i.fsf@intel.com> <20191003102254.dmwl6qimdca3dbrv@holly.lan> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="zCKi3GIZzVBPywwA" Content-Disposition: inline In-Reply-To: <20191003102254.dmwl6qimdca3dbrv@holly.lan> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --zCKi3GIZzVBPywwA Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > > >> I have been looking into adding Linux support for electronic privacy > > >> screens which is a feature on some new laptops which is built into t= he > > >> display and allows users to turn it on instead of needing to use a > > >> physical privacy filter. In discussions with my colleagues the idea = of > > >> using either /sys/class/backlight or /sys/class/leds but this new > > >> feature does not seem to quite fit into either of those classes. > > > > > > FWIW, it seems that you're not alone in this; 5.4 got some support for > > > such screens if I understand things correctly: > > > > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/= commit/?id=3D110ea1d833ad > >=20 > > Oh, I didn't realize it got merged already, I thought this was > > related... > >=20 > > So we've already replicated the backlight sysfs interface problem for > > privacy screens. :( >=20 > I guess... although the Thinkpad code hasn't added any standard > interfaces (no other laptop should be placing controls for a privacy > screen in /proc/acpi/ibm/... ). Maybe its not too late. There's new interface for controlling privacyguard... but perhaps we need better solution than what went in 5.4. Perhaps it should be reconsidered? Best regards, Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --zCKi3GIZzVBPywwA Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAl2ZylcACgkQMOfwapXb+vIvLwCgv8pM8435FkksDHNB1TjTxnow Zm8AoKrwhCDI1rdvOj6Y2H8UU21KaV9E =xgty -----END PGP SIGNATURE----- --zCKi3GIZzVBPywwA--