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[86.9.19.6]) by smtp.gmail.com with ESMTPSA id d193sm2240931wmd.0.2019.10.03.03.22.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Oct 2019 03:22:56 -0700 (PDT) Date: Thu, 3 Oct 2019 11:22:54 +0100 From: Daniel Thompson To: Jani Nikula Cc: 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: <20191003102254.dmwl6qimdca3dbrv@holly.lan> References: <20191002094650.3fc06a85@lwn.net> <87muei9r7i.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87muei9r7i.fsf@intel.com> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 03, 2019 at 11:19:13AM +0300, Jani Nikula wrote: > On Wed, 02 Oct 2019, Jonathan Corbet wrote: > > On Tue, 1 Oct 2019 10:09:46 -0600 > > Mat King wrote: > > > >> I have been looking into adding Linux support for electronic privacy > >> screens which is a feature on some new laptops which is built into the > >> 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=110ea1d833ad > > Oh, I didn't realize it got merged already, I thought this was > related... > > So we've already replicated the backlight sysfs interface problem for > privacy screens. :( 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. Daniel.