Re: /sys/class/power_supply/bq27200-0/capacity changed meaning between 4.1 and 4.4?

[Andrew F. Davis]

On 01/11/2016 03:48 PM, Andrew F. Davis wrote:
> On 01/11/2016 03:42 PM, Pavel Machek wrote:
> > Hi!
> >
> > > > Did /sys/class/power_supply/bq27200-0/capacity change meaning between
> > > > 4.1 and 4.4?
> >
> > > There was a resent overhaul of this driver and a lot of code is
> > > vestigial as you have seen. I've been meaning to continue
> > > cleaning it up, my next step would probably to bring up regmap
> >
> > Ok, 1wire is probably reasonable approach. But we have an regression
> > between 4.1 and 4.4, and to debug it is probably by reading code.
> >
> > I can't prove you caused the regression, but you basically rewrote the
> > driver, so it should be easier for you to spot the bug.
>
> Makes sense.
>
> > n900 has this variant:
> >
> >             bq27200: bq27200@55 {
> >                      compatible = "ti,bq27200";
> >                reg = <0x55>;
> >       };
>
> Hmmm, not sure if I have this one on hand, I'll see if I can find an
> n900 around here (they seem to be pretty popular around here for testing
> (had a lot of TI parts)).
>
> > Will you try?
> >
> > If not, tell me, and I can do it, but it will involve a lot of swaring...
>
> I'll give it a look over.

OK, I'm still looking for a test setup, but this was definitely a problem,
could you give this a try?:

diff --git a/drivers/power/bq27xxx_battery.c b/drivers/power/bq27xxx_battery.c
index 880233c..4fec3cf 100644
--- a/drivers/power/bq27xxx_battery.c
+++ b/drivers/power/bq27xxx_battery.c
@@ -470,8 +470,9 @@ static inline int bq27xxx_read(struct bq27xxx_device_info *di, int reg_index,
 static int bq27xxx_battery_read_soc(struct bq27xxx_device_info *di)
 {
 	int soc;
+	bool single = di->chip == BQ27000 || di->chip == BQ27010;
 
-	soc = bq27xxx_read(di, BQ27XXX_REG_SOC, false);
+	soc = bq27xxx_read(di, BQ27XXX_REG_SOC, single);
 
 	if (soc < 0)
 		dev_dbg(di->dev, "error reading State-of-Charge\n");