Re: /sys/class/power_supply/bq27200-0/capacity changed meaning between 4.1 and 4.4?
From: Pavel Machek
Date: Sun Jan 10 2016 - 03:06:47 EST
Hi!
> Did /sys/class/power_supply/bq27200-0/capacity change meaning between
> 4.1 and 4.4?
>
> It used to report battery capacity remaining in percent.
>
> Not sure what it reports now, but ain't in percent....
> The patch does not compile, but I should be sleeping, not trying to
> understand crazy code. Whoever wrote it, please fix it. Maybe you can
> just do
...and more crazy code :-(.
cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
if ((cache.flags & 0xff) == 0xff)
cache.flags = -1; /* read error */
/* WTF? bq27xxx returns -ERRNO
on error, we mask some bits off it, and then make it -1... */
...and one crazy optimalization...
if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
di->cache = cache;
...are we playing obfuscated C code contest, yet?
case POWER_SUPPLY_PROP_PRESENT:
val->intval = di->cache.flags < 0 ? 0 : 1;
...to decidegree C?
if (ret == 0)
pval->intval -= 2731; /* convert decidegree k to c */
as read takes enum, make it enum like this?
static inline int bq27xxx_read(struct bq27xxx_device_info *di, enum bq27xxx_reg_index reg_index,
bool single)
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html