Thread (9 messages) 9 messages, 2 authors, 2018-07-05

Charge counter on droid 4

From: Pavel Machek <hidden>
Date: 2018-06-15 08:32:02
Also in: linux-omap, lkml
Subsystem: power supply class/subsystem and drivers, the rest · Maintainers: Sebastian Reichel, Linus Torvalds

On Fri 2018-06-15 10:00:14, Pavel Machek wrote:
Hi!

Droid 4 has non-removable battery, yet the charge counter is reset to
near zero on each boot of linux.

Unfortunately, that makes charge counter pretty much useless on d4, as
the "battery full" and "battery empty" limits will be different during
each boot.
Hmm, and could we refrain from providing "power" values?

I was thinking great, we have hardware that does proper power
measuerement for us. No.... it is driver providing synthetic
values. As userland has enough information to do that itself, I
believe we should not do this in kernel.
diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
index 839e365..1610026 100644
--- a/drivers/power/supply/cpcap-battery.c
+++ b/drivers/power/supply/cpcap-battery.c
@@ -490,24 +490,6 @@ static int cpcap_battery_get_property(struct power_supply *psy,
 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
 		val->intval = latest->counter_uah;
 		break;
-	case POWER_SUPPLY_PROP_POWER_NOW:
-		tmp = (latest->voltage / 10000) * latest->current_ua;
-		val->intval = div64_s64(tmp, 100);
-		break;
-	case POWER_SUPPLY_PROP_POWER_AVG:
-		if (cached) {
-			tmp = cpcap_battery_cc_get_avg_current(ddata);
-			tmp *= (latest->voltage / 10000);
-			val->intval = div64_s64(tmp, 100);
-			break;
-		}
-		sample = latest->cc.sample - previous->cc.sample;
-		accumulator = latest->cc.accumulator - previous->cc.accumulator;
-		tmp = cpcap_battery_cc_to_ua(ddata, sample, accumulator,
-					     latest->cc.offset);
-		tmp *= ((latest->voltage + previous->voltage) / 20000);
-		val->intval = div64_s64(tmp, 100);
-		break;
 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
 		if (cpcap_battery_full(ddata))
 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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