On Friday, August 02, 2013 08:07:37 PM Felipe Contreras wrote: > On Fri, Aug 2, 2013 at 8:16 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote: > > On Friday, August 02, 2013 08:04:52 PM Felipe Contreras wrote: > >> On Fri, Aug 2, 2013 at 6:47 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote: > >> > On Friday, August 02, 2013 02:37:09 PM Felipe Contreras wrote: > >> >> If the _BCL package is descending, the first level (br->levels[2]) will > >> >> be 0, and if the number of levels matches the number of steps, we might > >> >> confuse a returned level to mean the index. > >> >> > >> >> For example: > >> >> > >> >> current_level = max_level = 100 > >> >> test_level = 0 > >> >> returned level = 100 > >> >> > >> >> In this case 100 means the level, not the index, and _BCM failed. But if > >> >> the _BCL package is descending, the index of level 0 is also 100, so we > >> >> assume _BQC is indexed, when it's not. > >> >> > >> >> This causes all _BQC calls to return bogus values causing weird behavior > >> >> from the user's perspective. For example: xbacklight -set 10; xbacklight > >> >> -set 20; would flash to 90% and then slowly down to the desired level > >> >> (20). > >> >> > >> >> The solution is simple; test anything other than the first level (e.g. > >> >> 1). > >> >> > >> >> Signed-off-by: Felipe Contreras <felipe.contreras@xxxxxxxxx> > >> > > >> > Looks reasonable. > >> > > >> > Aaron, what do you think? > >> > >> Aaron has a similar patch does many more checks. I think we should add > >> more checks, but I think those should go into a separate patch. > >> > >> This patch alone fixes a real problem, which is rather urgent to fix, > >> and I did it this way so it's trivial to review and merge. > > > > And I still would like to know the Aaron's opinion, what's wrong with that? > > Nothing. What's wrong with my clarification? You're not Aaron. :-) -- 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
