From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Subject: [PATCH 3/3] acpi-video: change acpi-video brightness_switch_enabled default to 0 Date: Mon, 5 May 2014 11:38:10 +0200 Message-ID: <1399282690-5381-3-git-send-email-hdegoede@redhat.com> References: <1399282690-5381-1-git-send-email-hdegoede@redhat.com> Return-path: Received: from mx1.redhat.com ([209.132.183.28]:25366 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755620AbaEEJia (ORCPT ); Mon, 5 May 2014 05:38:30 -0400 In-Reply-To: <1399282690-5381-1-git-send-email-hdegoede@redhat.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Zhang Rui , "Rafael J. Wysocki" , Len Brown Cc: Aaron Lu , edm , Balint Szigeti , AnAkkk , lou.cardone@gmail.com, linux-acpi@vger.kernel.org, Hans de Goede acpi-video is unique in that it not only generates brightness up/down keypresses, but also (sometimes) actively changes the brightness itself. This presents an inconsistent kernel interface to userspace, basically there are 2 different scenarios, depending on the laptop model: 1) On some laptops a brightness up/down keypress means: show a brightness osd with the current brightness, iow it is a brightness has changed notification. 2) Where as on (a lot of) other laptops it means a brightness up/down key was pressed, deal with it. Most of the desktop environments interpret any press as in scenario 2, and change the brightness up / down as a response to the key events, causing it to be changed twice, once by acpi-video and once by the DE. With the new default for video.use_native_backlight we will be moving even more laptops over to behaving as in scenario 2. Making the remaining laptops even more of a weird exception. Also note that it is hard to detect scenario 1 properly in userspace, and AFAIK none of the DE-s deals with it. Therefor this commit changes the default of brightness_switch_enabled to 0 making its behavior consistent with all the other backlight drivers. Signed-off-by: Hans de Goede --- drivers/acpi/video.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index cebc74d..34198b2 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -68,7 +68,7 @@ MODULE_AUTHOR("Bruno Ducrot"); MODULE_DESCRIPTION("ACPI Video Driver"); MODULE_LICENSE("GPL"); -static bool brightness_switch_enabled = 1; +static bool brightness_switch_enabled; module_param(brightness_switch_enabled, bool, 0644); /* -- 1.9.0