On Fri, Mar 13, 2009 at 11:06:46AM -0700, mjg59@xxxxxxxxxxxxx wrote: > On Fri, Mar 13, 2009 at 12:58:12PM -0500, Terence Ripperda wrote: > > On Fri, Mar 13, 2009 at 10:47:26AM -0700, mjg59@xxxxxxxxxxxxx wrote: > > > Yeah, this is the bit I don't understand. The design we've adopted for > > > output switching ignores any BIOS provided information, and instead just > > > enables outputs based on the user preferences. The X driver then has > > > responsibility for performing the actual switch. Nouveau appears to be > > > able to handle this on nvidia platforms without any problem. So, really, > > > I guess I'm not clear on what functionality NVIF is intended to provide > > > here. Is it impossible to enable outputs on some systems without it? > > > > yes, this is what I mean by platform customizations. some notebook platforms > > will rely on the DCS/DGS methods to perform hotkeys, others will rely on other > > mechanisms, such as NVIF methods. I suspect you'll find that nouveau's mechanism > > will work on a lot of notebooks, but not work at all on other notebooks. > > Can we make sure we're clear on terminology here? I'm using hotkey > events to refer purely to the process by which the user hits a key, the > firmware generates a notification, the kernel catches this notification > and generates a KEY_SWITCHVIDEOMODE which we then catch in the user > session. > > There's then the issue of actually performing a display output change in > response to this. This is curently handled by generating an xrandr > request. The X driver (potentially in combination with the kernel > driver, in a kernel modesetting world) then enables or disables outputs > as appropriate. > > The actual output changing is related to but not dependent upon the > hotkey press, as the user may want to change output configuration via > the graphical UI rather than by hitting the hotkey. So is the NVIF > functionality required for generating the event in the first place, > performing the actual output switch or simply providing the firmware's > preferred set of enabled outputs? sure, I sometimes use the wrong terminology; I mean a display change hotkey, where a keypress generates a display change event via the sbios/acpi subsystem. I do not mean a case where a userspace daemon detects keypresses independent of the sbios/acpi/kernel. I was trying to clarify whether nouveau was using such a mechanism. NVIF methods implement both notification and query commands. so it's required for generating the event and querying the firmware's preferred set of enabled outputs. > > -- > Matthew Garrett | mjg59@xxxxxxxxxxxxx ----------------------------------------------------------------------------------- This email message is for the sole use of the intended recipient(s) and may contain confidential information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message. ----------------------------------------------------------------------------------- -- 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
