apm_power: improve battery finding algorithm
Prior to this patch, if use_for_apm unspecified, apm_power able
to choice batteries according to their charge only.
This patch adds ability to choice batteries according to their charge,
energy, use_for_apm flag, and fallback to any battery if it failed to
decide.
Patch is mandatory to report Apple PMU batteries through legacy
/proc/apm interface using power supply class.
Signed-off-by: Anton Vorontsov <cbou@mail.ru>
diff --git a/drivers/power/apm_power.c b/drivers/power/apm_power.c
index 32ebfd7..3928e7c 100644
--- a/drivers/power/apm_power.c
+++ b/drivers/power/apm_power.c
@@ -26,28 +26,65 @@
static void find_main_battery(void)
{
struct device *dev;
- struct power_supply *bat, *batm;
+ struct power_supply *bat = NULL;
+ struct power_supply *max_charge_bat = NULL;
+ struct power_supply *max_energy_bat = NULL;
union power_supply_propval full;
int max_charge = 0;
+ int max_energy = 0;
main_battery = NULL;
- batm = NULL;
+
list_for_each_entry(dev, &power_supply_class->devices, node) {
bat = dev_get_drvdata(dev);
- /* If none of battery devices cantains 'use_for_apm' flag,
- choice one with maximum design charge */
- if (!PSY_PROP(bat, CHARGE_FULL_DESIGN, &full)) {
- if (full.intval > max_charge) {
- batm = bat;
- max_charge = full.intval;
- }
+
+ if (bat->use_for_apm) {
+ /* nice, we explicitly asked to report this battery. */
+ main_battery = bat;
+ return;
}
- if (bat->use_for_apm)
- main_battery = bat;
+ if (!PSY_PROP(bat, CHARGE_FULL_DESIGN, &full) ||
+ !PSY_PROP(bat, CHARGE_FULL, &full)) {
+ if (full.intval > max_charge) {
+ max_charge_bat = bat;
+ max_charge = full.intval;
+ }
+ } else if (!PSY_PROP(bat, ENERGY_FULL_DESIGN, &full) ||
+ !PSY_PROP(bat, ENERGY_FULL, &full)) {
+ if (full.intval > max_energy) {
+ max_energy_bat = bat;
+ max_energy = full.intval;
+ }
+ }
}
- if (!main_battery)
- main_battery = batm;
+
+ if ((max_energy_bat && max_charge_bat) &&
+ (max_energy_bat != max_charge_bat)) {
+ /* try guess battery with more capacity */
+ if (!PSY_PROP(max_charge_bat, VOLTAGE_MAX_DESIGN, &full)) {
+ if (max_energy > max_charge * full.intval)
+ main_battery = max_energy_bat;
+ else
+ main_battery = max_charge_bat;
+ } else if (!PSY_PROP(max_energy_bat, VOLTAGE_MAX_DESIGN,
+ &full)) {
+ if (max_charge > max_energy / full.intval)
+ main_battery = max_charge_bat;
+ else
+ main_battery = max_energy_bat;
+ } else {
+ /* give up, choice any */
+ main_battery = max_energy_bat;
+ }
+ } else if (max_charge_bat) {
+ main_battery = max_charge_bat;
+ } else if (max_energy_bat) {
+ main_battery = max_energy_bat;
+ } else {
+ /* give up, try the last if any */
+ main_battery = bat;
+ }
}
static int calculate_time(int status)