Messages in this thread | | | Date | Mon, 12 Mar 2012 10:18:52 -0500 | From | Seth Forshee <> | Subject | Re: [PATCH v2] platform/x86: Add driver for Apple gmux device |
| |
On Mon, Mar 12, 2012 at 03:07:17PM +0000, Matthew Garrett wrote: > > We also have the problem of gmux_backlight versus acpi_video. On most > > machines with a gmux the acpi_video backlight interface is present but > > just doesn't work. This problem isn't just limited to Apples. I'm of the > > opinion that we need a more generalized solution for arbitrating between > > the backlight interfaces present on a given machine, but I haven't had a > > chance to really think about what that would look like. > > The ACPI code appears to be trapping into system management mode, so > figuring out what it's meant to do is going to be awkward. I think > having a hook in the ACPI video driver to deregister it in cases where > we know it doesn't work is legitimate, but since it presumably works > under Windows it'd be nice to figure out what's broken about it.
Why do you presume it works under Windows? Boot camp installs a pile of drivers for Windows, one of those could be a driver for the backlight. I don't know either way. But it's pretty clear that MacOS is using the gmux for the backlight when it is present from the reverse engineering work done by others.
Seth
| |