It seems that the USB type was chosen to fit into a upower heuristic that still exists (see [1], [2]). Looking at the upower code I suspect that swapping to the Battery type will at least cause "UP_DEVICE_KIND_TABLET" to no longer be used for our dongle-based wireless devices (Bluetooth-based might still be fine though). We haven't sold dongle-based devices in a while, but they're definitely still out there. If the batteries in those devices are seen as system batteries that could cause a problem -- e.g. triggering hibernation when the tablet battery gets low. I think it would be wise to test this first to see if there's any obvious real-world fallout from the change... [1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=96983296281507f049425b84f0d244c40d506eba [2]: https://cgit.freedesktop.org/upower/tree/src/linux/up-device-supply.c Jason --- Now instead of four in the eights place / you’ve got three, ‘Cause you added one / (That is to say, eight) to the two, / But you can’t take seven from three, / So you look at the sixty-fours.... On Thu, Apr 7, 2022 at 1:52 PM Bastien Nocera <hadess@xxxxxxxxxx> wrote: > > POWER_SUPPLY_TYPE_USB seems to only ever be used by USB ports that are > used to charge the machine itself (so a "system" scope), like the > single USB port on a phone, rather than devices. > > The wacom_sys driver is the only driver that sets its device battery as > being a USB type, which doesn't seem correct based on its usage, so > switch it to be a battery type like all the other USB-connected devices. > > Signed-off-by: Bastien Nocera <hadess@xxxxxxxxxx> > --- > drivers/hid/wacom_sys.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c > index 066c567dbaa2..620fe74f5676 100644 > --- a/drivers/hid/wacom_sys.c > +++ b/drivers/hid/wacom_sys.c > @@ -1777,7 +1777,7 @@ static int __wacom_initialize_battery(struct wacom *wacom, > bat_desc->get_property = wacom_battery_get_property; > sprintf(battery->bat_name, "wacom_battery_%ld", n); > bat_desc->name = battery->bat_name; > - bat_desc->type = POWER_SUPPLY_TYPE_USB; > + bat_desc->type = POWER_SUPPLY_TYPE_BATTERY; > bat_desc->use_for_apm = 0; > > ps_bat = devm_power_supply_register(dev, bat_desc, &psy_cfg); > -- > 2.35.1 >
