On Wed, Sep 24, 2014 at 04:34:32PM +0100, Mark Rutland wrote: > On Wed, Sep 24, 2014 at 04:14:48PM +0100, Frans Klaver wrote: > > On Wed, Sep 24, 2014 at 03:38:49PM +0100, Mark Rutland wrote: > > > On Wed, Sep 24, 2014 at 03:22:22PM +0100, Frans Klaver wrote: > > > You mention that there's a GPIO that can be used to detect the battery > > > presence. Why can't the driver always probe and then on check for the > > > presence of the battery dynamically using that GPIO? That should cover > > > both cases. > > > > I would say that this was the case before [1] was done. The GPIO is > > optional and if not configured, the presence or absence of the battery > > is detected by checking a status register much like probe() currently > > does. It seems all cases were covered before that patch. If you worry > > about speed, you should use the GPIO. I wonder if we might be able to > > revert [1] without doing much harm. > > But reverting that would re-introduce the lag on some systems, no? Given > the wording of the original commit I would guess that the GPIO wasn't > available. Perhaps Olof or Anton can enlighten us? It probably would yes. The battery_detect gpio was last touched in 2011, the probe check was added somewhere in 2012. We could keep it as a compile option. > In the cases where a GPIO is available, I think we should be able to be > less pessimistic. Is a GPIO available in your case? We don't have the battery_detect pin available. Incidentally, a bit of lag reading out the battery is not a problem for us. > Mark. > > > > > Thanks, > > Frans > > > > [1] a22b41a31e53 "sbs-battery: Probe should try talking to the device" > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
