On Fri, 2009-08-21 at 19:51 +0800, Pavel Machek wrote: > Hi! > > > > > Could you please look at the documentation about ALS sysfs class in the > > > > patch I sent out just now, and comment on that one please? thanks! > > > > > > I did. The interface is too ugly to live. > > > > Hi, Pavel, > > > > I tried to convert the ALS sysfs I/F to two attributes only, i.e. > > illuminance and adjustment. > > But I found several potential problems. > > 1. the illuminance to display adjustment mappings can not be convert to > > a brightness level smoothly. > > for example, > > illuminance adjustment > > 1 600 70 > > 2 900 100 > > 3 1500 120 > > when the current illuminance is not one of the values listed in the > > mappings, e.g. 750, the ALS driver don't have enough knowledge to get > > the proper display adjustment, especially that a proper display > > adjustment would be easy to select a proper brightness level. > > We'd better leave this to user space, which is more flexible. > > Well, what interpolation does ACPI specs suggest to do? Well, the spec says that "Extrapolation of the values between these points is OS-specific", and it uses a piecewise linear approximation in an example. > Maybe it is > easier to have linear interpolation in the kernel than to have ugly > 20-file interface? yes. we can do that. refreshed patch will be sent out later. thanks, rui -- 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
