On Sun, Oct 17, 2010 at 03:19:53AM -0200, Henrique de Moraes Holschuh wrote: > On Sun, 17 Oct 2010, Rafael J. Wysocki wrote: > > In fact, the driver is supposed to return -ENODATA in that case, which will > > result in the read from /sys/class/power_supply/BAT0/current_now > > fail (I guess upower should be able to cope with that). > > ENODATA? Shouldn't it be ENXIO? There is no non-blocking data stream > involved in a sysfs attribute. Using ENODATA and ENXIO appears to solve the problem (upower reports a rate of 0.0). However when plugging the battery in after previously only being on AC power none of the /sys/class/power_supply/BAT0/uevent:* files are created so upower never realises a battery has been plugged in. A further issue with ENXIO is is the following repeatedly appears in dmesg: power_supply BAT0: driver failed to report `current_now' property > Of course, the RIGHT thing would be to not expose in sysfs attributes > that are unsupported by the firmware/hardware in the first place, but > that's easier said than done. My understanding is that this very hard to do because you can't tell if the problem was transient (battery settling) or permanent (feature not supported). -- 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
