On Fri, Oct 22, 2010 at 01:31:28PM +0100, Richard Hughes wrote: > On 21 October 2010 17:54, Sitsofe Wheeler <sitsofe@xxxxxxxxx> wrote: > > I guess there are a whole bunch of other attributes that could > > theoretically be -1 and shouldn't be used if they return it... > > I think checking for <0 is probably a good idea, and I'm a little > surprised we don't do this already. Patch welcome, if this is what you > decide to do. I can only guess that at some point in upower's past negative values for current_rate were found to be valid so upower took the route of making them absolute to work around that behaviour. If so, it would be good to know whether there are still devices in this category running a stock kernel. If the latest patch to return -ENODEV goes in, then there's the possibility for upower to detect the unknown state and report unknown back to its users. Would the existing interfaces support outputting unknown instead of a number? If not (and there are no plans to) I suspect the best thing to do is to remove the test for 0xffff and continue to return 0. -- Sitsofe | http://sucs.org/~sits/ -- 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
