From: Yves-Alexis Perez <corsac@debian.org> To: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Henrique de Moraes Holschuh <hmh@debian.org>, seth.forshee@canonical.com, daniel.vetter@ffwll.ch, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, rjw@sisk.pl, linux-acpi@vger.kernel.org, joeyli.kernel@gmail.com, lenb@kernel.org Subject: Re: [PATCH 0/3] Fix backlight issues on some Windows 8 systems Date: Tue, 25 Jun 2013 22:43:57 +0200 [thread overview] Message-ID: <1372193037.8189.24.camel@scapa> (raw) In-Reply-To: <20130625160848.GA27123@srcf.ucam.org> [-- Attachment #1.1: Type: text/plain, Size: 2311 bytes --] On mar., 2013-06-25 at 17:08 +0100, Matthew Garrett wrote: > On Sat, Jun 22, 2013 at 11:46:39PM +0200, Yves-Alexis Perez wrote: > > > Before Linux support for acpi_osi("Windows 2012") (and when booting with > > acpi_osi="!Windows 2012"), brightness keys were handled by the kernel > > just fine, whether in console, in the display manager or in my desktop > > environment (Xfce). xfce4-power-manager just needs to be told that the > > brightness keys are already handled and it doesn't need to do anything. > > Right, the kernel has special-casing to hook the backlight keys up to > the ACPI backlight control. This is an awful thing, because there's no > way to detect this case other than parsing a single driver-specific > module parameter. I'm not sure what that means. To detect what case exactly? That the brightness is handled by video.ko? > > Could this functionality be duplicated across other backlight drivers? > Not easily. The ACPI driver receives keypresses and performs backlight > control. The i915 driver doesn't receive keypresses. We could easily tie > certain keycodes into backlight events, but which backlight should they > control? You're really starting to get into the kind of complex policy > decision that's best left to userspace, which is where it should have > been to begin with. > Well, I get the reasoning, but I'm not sure I agree. That means userspace behavior is inconsistent depending on who does it (gnome-power-manager, gnome-setting-daemon, whatever), and it usually means there's nothing handling the brightness before those are running, not to mention people not running them because they don't run a full blown desktop environment (until someone starts thinking it's a good idea to handle brightness in systemd). And in the end, the user just want the brightness keys to correctly handle the brightness, full stop. Having multiple brightness daemons using different policies on different hardware is a nightmare for the end user, imho. From a user point of view, having it handled all in the kernel works really pretty fine and is completely transparent (I have to admit that from that point of view, it was even better when it was handled by the EC but those times seem long gone). Regards, -- Yves-Alexis [-- Attachment #1.2: This is a digitally signed message part --] [-- Type: application/pgp-signature, Size: 490 bytes --] [-- Attachment #2: Type: text/plain, Size: 159 bytes --] _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
WARNING: multiple messages have this Message-ID (diff)
From: Yves-Alexis Perez <corsac@debian.org> To: Matthew Garrett <mjg59@srcf.ucam.org> Cc: linux-acpi@vger.kernel.org, seth.forshee@canonical.com, joeyli.kernel@gmail.com, daniel.vetter@ffwll.ch, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, lenb@kernel.org, rjw@sisk.pl, Henrique de Moraes Holschuh <hmh@debian.org> Subject: Re: [PATCH 0/3] Fix backlight issues on some Windows 8 systems Date: Tue, 25 Jun 2013 22:43:57 +0200 [thread overview] Message-ID: <1372193037.8189.24.camel@scapa> (raw) In-Reply-To: <20130625160848.GA27123@srcf.ucam.org> [-- Attachment #1: Type: text/plain, Size: 2311 bytes --] On mar., 2013-06-25 at 17:08 +0100, Matthew Garrett wrote: > On Sat, Jun 22, 2013 at 11:46:39PM +0200, Yves-Alexis Perez wrote: > > > Before Linux support for acpi_osi("Windows 2012") (and when booting with > > acpi_osi="!Windows 2012"), brightness keys were handled by the kernel > > just fine, whether in console, in the display manager or in my desktop > > environment (Xfce). xfce4-power-manager just needs to be told that the > > brightness keys are already handled and it doesn't need to do anything. > > Right, the kernel has special-casing to hook the backlight keys up to > the ACPI backlight control. This is an awful thing, because there's no > way to detect this case other than parsing a single driver-specific > module parameter. I'm not sure what that means. To detect what case exactly? That the brightness is handled by video.ko? > > Could this functionality be duplicated across other backlight drivers? > Not easily. The ACPI driver receives keypresses and performs backlight > control. The i915 driver doesn't receive keypresses. We could easily tie > certain keycodes into backlight events, but which backlight should they > control? You're really starting to get into the kind of complex policy > decision that's best left to userspace, which is where it should have > been to begin with. > Well, I get the reasoning, but I'm not sure I agree. That means userspace behavior is inconsistent depending on who does it (gnome-power-manager, gnome-setting-daemon, whatever), and it usually means there's nothing handling the brightness before those are running, not to mention people not running them because they don't run a full blown desktop environment (until someone starts thinking it's a good idea to handle brightness in systemd). And in the end, the user just want the brightness keys to correctly handle the brightness, full stop. Having multiple brightness daemons using different policies on different hardware is a nightmare for the end user, imho. From a user point of view, having it handled all in the kernel works really pretty fine and is completely transparent (I have to admit that from that point of view, it was even better when it was handled by the EC but those times seem long gone). Regards, -- Yves-Alexis [-- Attachment #2: This is a digitally signed message part --] [-- Type: application/pgp-signature, Size: 490 bytes --]
next prev parent reply other threads:[~2013-06-25 20:43 UTC|newest] Thread overview: 108+ messages / expand[flat|nested] mbox.gz Atom feed top 2013-06-09 23:01 [PATCH 0/3] Fix backlight issues on some Windows 8 systems Matthew Garrett 2013-06-09 23:01 ` [PATCH 1/3] acpi: video: add function to support unregister backlight interface Matthew Garrett 2013-06-09 23:01 ` [PATCH 2/3] ACPICA: Add interface for getting latest OS version requested via _OSI Matthew Garrett 2013-06-17 22:31 ` Rafael J. Wysocki 2013-06-17 22:37 ` Matthew Garrett 2013-06-17 22:37 ` Matthew Garrett 2013-06-18 0:42 ` Rafael J. Wysocki 2013-06-25 23:23 ` Rafael J. Wysocki 2013-07-02 13:56 ` [PATCH 0/2] Expose OSI version Aaron Lu 2013-07-02 13:59 ` [PATCH 1/2] ACPICA: expose " Aaron Lu 2013-07-02 14:01 ` [PATCH 2/2] ACPI / OSL: add a wrapper function to return " Aaron Lu 2013-07-03 21:57 ` Rafael J. Wysocki 2013-07-04 1:24 ` Aaron Lu 2013-07-05 19:52 ` Rafael J. Wysocki 2013-06-09 23:01 ` [PATCH 3/3] i915: Don't provide ACPI backlight interface if firmware expects Windows 8 Matthew Garrett 2013-06-10 7:40 ` Daniel Vetter 2013-06-10 9:22 ` joeyli 2013-06-10 14:09 ` Alex Deucher 2013-06-14 6:47 ` Aaron Lu 2013-06-14 17:29 ` Matthew Garrett 2013-06-14 17:29 ` Matthew Garrett 2013-06-15 1:26 ` Aaron Lu 2013-06-15 1:38 ` Matthew Garrett 2013-06-15 1:38 ` Matthew Garrett 2013-06-15 4:14 ` Aaron Lu 2013-06-15 4:14 ` Aaron Lu 2013-06-15 4:19 ` Matthew Garrett 2013-06-15 12:29 ` Aaron Lu 2013-06-15 12:29 ` Aaron Lu 2013-06-15 15:16 ` Matthew Garrett 2013-06-15 18:29 ` Daniel Vetter 2013-06-15 18:44 ` Matthew Garrett 2013-06-15 20:27 ` Rafael J. Wysocki 2013-06-15 20:35 ` Daniel Vetter 2013-07-05 12:20 ` Rafael J. Wysocki 2013-07-05 20:00 ` Rafael J. Wysocki 2013-07-05 21:40 ` Rafael J. Wysocki 2013-07-05 22:23 ` Rafael J. Wysocki 2013-07-06 5:45 ` Aaron Lu 2013-07-06 13:33 ` Rafael J. Wysocki 2013-07-07 13:19 ` Rafael J. Wysocki 2013-07-07 13:19 ` Rafael J. Wysocki 2013-07-08 8:00 ` Aaron Lu 2013-07-13 0:46 ` [Update][PATCH] ACPI / video / i915: Remove ACPI backlight " Rafael J. Wysocki 2013-07-15 2:36 ` Aaron Lu 2013-07-15 11:42 ` Rafael J. Wysocki 2013-07-16 3:24 ` Aaron Lu 2013-07-16 11:54 ` Rafael J. Wysocki 2013-07-15 13:06 ` Igor Gnatenko 2013-07-15 13:06 ` Igor Gnatenko 2013-07-15 23:53 ` Rafael J. Wysocki 2013-07-16 7:45 ` Igor Gnatenko 2013-07-16 7:45 ` Igor Gnatenko 2013-07-16 13:32 ` Igor Gnatenko 2013-07-16 13:32 ` Igor Gnatenko 2013-07-16 17:08 ` Matthew Garrett 2013-07-16 17:08 ` Matthew Garrett 2013-07-16 22:01 ` Rafael J. Wysocki 2013-07-17 5:16 ` Igor Gnatenko 2013-07-17 5:16 ` Igor Gnatenko 2013-07-17 11:38 ` Rafael J. Wysocki 2013-07-17 12:03 ` Igor Gnatenko 2013-07-17 12:03 ` Igor Gnatenko 2013-06-10 11:59 ` [PATCH 0/3] Fix backlight issues on some Windows 8 systems Rafael J. Wysocki 2013-06-10 13:48 ` Matthew Garrett 2013-06-10 13:48 ` Matthew Garrett 2013-06-11 13:08 ` Seth Forshee 2013-06-22 21:46 ` Yves-Alexis Perez 2013-06-25 16:08 ` Matthew Garrett 2013-06-25 16:10 ` Daniel Vetter 2013-06-25 16:13 ` Matthew Garrett 2013-06-25 20:43 ` Yves-Alexis Perez [this message] 2013-06-25 20:43 ` Yves-Alexis Perez 2013-06-25 20:54 ` Matthew Garrett 2013-06-25 21:10 ` Yves-Alexis Perez 2013-06-25 21:14 ` Matthew Garrett 2013-06-25 21:30 ` Yves-Alexis Perez 2013-06-25 21:33 ` Matthew Garrett 2013-06-25 21:33 ` Matthew Garrett 2013-06-25 21:46 ` Yves-Alexis Perez 2013-06-25 21:49 ` Matthew Garrett 2013-06-25 21:49 ` Matthew Garrett 2013-07-17 15:51 ` Felipe Contreras 2013-07-17 19:57 ` Yves-Alexis Perez 2013-07-18 0:16 ` [Update][PATCH " Rafael J. Wysocki 2013-07-18 0:20 ` [PATCH 1/3] ACPICA: expose OSI version Rafael J. Wysocki 2013-07-18 5:38 ` Igor Gnatenko 2013-07-18 5:38 ` Igor Gnatenko 2013-07-18 0:21 ` [PATCH 2/3] ACPI / video: Always call acpi_video_init_brightness() on init Rafael J. Wysocki 2013-07-18 5:40 ` Igor Gnatenko 2013-07-18 5:40 ` Igor Gnatenko 2013-07-18 0:22 ` [PATCH 3/3] ACPI / video / i915: No ACPI backlight if firmware expects Windows 8 Rafael J. Wysocki 2013-07-20 13:16 ` [Update][PATCH 0/3] Fix backlight issues on some Windows 8 systems Felipe Contreras 2013-07-26 13:24 ` Jani Nikula 2013-07-29 18:01 ` Felipe Contreras 2013-07-30 5:03 ` Jani Nikula 2013-07-31 0:01 ` Rafael J. Wysocki 2013-07-31 0:01 ` Matthew Garrett 2013-07-31 0:01 ` Matthew Garrett 2013-07-31 6:48 ` Igor Gnatenko 2013-07-31 6:48 ` Igor Gnatenko 2013-07-31 9:08 ` Aaron Lu 2013-08-07 7:44 ` Backlight control only in the kernel? Borislav Petkov 2013-08-07 9:03 ` Aaron Lu 2013-08-07 10:34 ` Borislav Petkov 2013-08-07 10:36 ` Matthew Garrett 2013-08-07 10:36 ` Matthew Garrett 2013-08-07 11:04 ` Borislav Petkov
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1372193037.8189.24.camel@scapa \ --to=corsac@debian.org \ --cc=daniel.vetter@ffwll.ch \ --cc=dri-devel@lists.freedesktop.org \ --cc=hmh@debian.org \ --cc=intel-gfx@lists.freedesktop.org \ --cc=joeyli.kernel@gmail.com \ --cc=lenb@kernel.org \ --cc=linux-acpi@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=mjg59@srcf.ucam.org \ --cc=rjw@sisk.pl \ --cc=seth.forshee@canonical.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.