From 2949136b152e94aa3b57da5130bcb9022724debe Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Thu, 17 Jun 2021 18:14:53 +0200 Subject: [PATCH] linux: Fix < 0.01 W energy-rate readings from power_now sysfs property Currently, if a power supplies' power_now sysfs file reports discharge rates < 0.01 W, the code will try to calculate the discharge rate from the legacy sysfs files. On new kernels where those don't exist, this produces wrong results. For example, on a dual-battery Thinkpad T450s, while the external battery is discharging, the internal battery reports power_now = 0, but the corresponding upower energy-rate field incorrectly reads about 2.3 W. This patch fixes the issue by falling back to the legacy code only if the legacy current_now sysfs file exists. Closes: #7, #44 --- src/linux/up-device-supply.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/src/linux/up-device-supply.c b/src/linux/up-device-supply.c index 3ebbd88..4236ce4 100644 --- a/src/linux/up-device-supply.c +++ b/src/linux/up-device-supply.c @@ -682,8 +682,9 @@ up_device_supply_refresh_battery (UpDeviceSupply *supply, state = up_device_supply_get_state (native); /* this is the new value in uW */ - energy_rate = fabs (g_udev_device_get_sysfs_attr_as_double_uncached (native, "power_now") / 1000000.0); - if (energy_rate < 0.01) { + if (g_udev_device_has_sysfs_attr (native, "power_now")) { + energy_rate = fabs (g_udev_device_get_sysfs_attr_as_double_uncached (native, "power_now") / 1000000.0); + } else { gdouble charge_full; /* convert charge to energy */ -- GitLab