| Message ID | 1399282690-5381-3-git-send-email-hdegoede@redhat.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 05/05/2014 05:38 PM, Hans de Goede wrote: > 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 <hdegoede@redhat.com> Reviewed-by: Aaron Lu <aaron.lu@intel.com> Note that the Documentation/kernel-parameters.txt has to be modified accordingly to change the default value for video.brightness_switch_enabled to 0. Thanks, Aaron > --- > 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); > > /* > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, On 05/06/2014 04:01 AM, Aaron Lu wrote: > On 05/05/2014 05:38 PM, Hans de Goede wrote: >> 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 <hdegoede@redhat.com> > > Reviewed-by: Aaron Lu <aaron.lu@intel.com> > > Note that the Documentation/kernel-parameters.txt has to be modified > accordingly to change the default value for video.brightness_switch_enabled > to 0. Good one, I'll send a v2 with this fixed. Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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); /*
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 <hdegoede@redhat.com> --- drivers/acpi/video.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)