On Tuesday, March 10, 2015 11:42:21 PM Hans de Goede wrote: > Hi, > > On 03/10/2015 11:25 PM, Rafael J. Wysocki wrote: > > On Wednesday, March 04, 2015 10:50:20 AM Aaron Lu wrote: > >> On 03/03/2015 09:11 PM, Hans de Goede wrote: > >>> Hi, > >>> > >>> On 03-03-15 09:26, Aaron Lu wrote: > >>>> On 03/03/2015 03:39 PM, Hans de Goede wrote: > >>>>> The native backlight behavior (so not registering both the acpi-video and the > >>>>> vendor backlight driver) can be useful on some non win8 machines too, allow > >>>>> the user to force this behavior by passing video.use_native_backlight=2 > >>>>> on the kernel commandline. > >>>> > >>>> Just bikeshedding, what about doing it this way? > >>>> > >>>> In the acpi_video_use_native_backlight function: > >>>> 1 If user has set a cmdline option, use that(no matter if it is a win8 > >>>> system or not); > >>>> 2 If the system is in a DMI table, use that(no matter if it is a win8 > >>>> system or not); > >>>> 3 return true if this is a win8 system; false otherwise. > >>>> > >>>> Something like this: > >>> > >>> That works for me, and has the added advantage of not changing the > >>> cmdline syntax (but it does change the cmdline behavior ...). > >> > >> Oh yes, I didn't consider this. Not sure how much impact this will have, > >> but I don't see an immediate problem with it, so let's see. > >> > >>> > >>> So going either way is fine with me. > >>> > >>> Aaron's version is: > >>> > >>> Acked-by: Hans de Goede <hdegoede@xxxxxxxxxx> > >> > >> Thanks. Here is the full patch: > >> > >> From: Aaron Lu <aaron.lu@xxxxxxxxx> > >> Date: Wed, 4 Mar 2015 10:24:58 +0800 > >> Subject: [PATCH] acpi: video: Allow forcing native backlight on non win8 > >> machines > >> > >> The native backlight behavior (so not registering both the acpi-video > >> and the vendor backlight driver) can be useful on some non win8 machines > >> too, so change the behavior of the video.use_native_backlight=1 or 0 > >> kernel cmdline option to be: if user has set video.use_native_backlight=1 > >> or 0, use that no matter if it is a win8 system or not. Also, we will > >> put some known systems into the DMI table to make them either use native > >> backlight interface or not, so the use_native_backlight_dmi is used to > >> reflect that. > >> > >> Original-by: Hans de Goede <hdegoede@xxxxxxxxxx> > >> Signed-offby: Aaron Lu <aaron.lu@xxxxxxxxx> > >> Acked-by: Hans de Goede <hdegoede@xxxxxxxxxx> > >> --- > >> drivers/acpi/video.c | 9 +++++---- > >> 1 file changed, 5 insertions(+), 4 deletions(-) > >> > >> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c > >> index debd30917010..4cd0c8a4fd9d 100644 > >> --- a/drivers/acpi/video.c > >> +++ b/drivers/acpi/video.c > >> @@ -84,7 +84,7 @@ module_param(allow_duplicates, bool, 0644); > >> */ > >> static int use_native_backlight_param = -1; > >> module_param_named(use_native_backlight, use_native_backlight_param, int, 0444); > >> -static bool use_native_backlight_dmi = true; > >> +static int use_native_backlight_dmi = -1; > > > > So can we have proper symbols instead of these numbers, please? > > So you want to have a native_backlight enum or some such ? with -1 being not_set ? Yes, something like that. -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
