Submit FS#10718. Small fix to calculation of estimated runtime to avoid negative results.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@24146 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 3 insertions, 6 deletions

diff --git a/firmware/powermgmt.c b/firmware/powermgmt.c
index 041fed0361..5f488810ac 100644
--- a/firmware/powermgmt.c
+++ b/firmware/powermgmt.c
@@ -282,17 +282,14 @@ static void battery_status_update(void)
     else
 #endif
     /* discharging: remaining running time */
-    if ((battery_millivolts + 20) > percent_to_volt_discharge[0][0]) {
+    if (battery_millivolts > percent_to_volt_discharge[0][0]) {
+        /* linear extrapolation */
         powermgmt_est_runningtime_min = (level + battery_percent)*60
                 * battery_capacity / 200 / runcurrent();
     }
-    else if (battery_millivolts <= battery_level_shutoff[0]) {
+    if (0 > powermgmt_est_runningtime_min) {
         powermgmt_est_runningtime_min = 0;
     }
-    else {
-        powermgmt_est_runningtime_min =
-            (battery_millivolts - battery_level_shutoff[0]) / 2;
-    }
 
     battery_percent = level;
     send_battery_level_event();