On Wed, 2009-07-15 at 16:38 +0800, Zhang Rui wrote: > On Wed, 2009-07-15 at 16:22 +0800, Richard Purdie wrote: > > We don't have one that I'm aware of. > > > > The first question is what information and configuration options are we > > likely to have with ALS sensors? If its just a light level reading, the > > input subsystem is ideally suited for sharing that. Is there > > configuration we need to expose? > > > For an ACPI ALS device, only these two are mandatory > 1. the current ambient light illuminance. > 2. A list of luminance mappings, including the "display luminance > adjustment" and "ambient light illuminance", which can be used by OS to > determine the ambient light policy. So there are basically two values we're ever interested in at a given point in time. The current ambient light reading and the corresponding display luminance adjustment. Both of those could just be exposed as an input device really? > IMO, the ALS driver should just export these info to user space, and we > can do the display backlight adjustment in user space, > via /sys/class/backlight. Agreed, userspace should be where policy is decided. Having a standalone module which connected the two together with a "default" policy might be acceptable too though? If userspace then wants to handle things it just makes sure the module is not loaded. Cheers, Richard -- Richard Purdie Intel Open Source Technology Centre -- 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
