On 01/10/2016 02:06 AM, Pavel Machek wrote:

Hi!

quoted

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....

quoted

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... */
	

This is probably left over from when the driver was 1wire only, which seems
to fail by just reading back all ones. Not sure why the -1 though?

...and one crazy optimalization...

         if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
	                di->cache = cache;

Hmmm, I think the lines above it:

	if (di->cache.capacity != cache.capacity)
		power_supply_changed(di->bat);

were at one point rolled into this as so:

	if (memcmp(&di->cache, &cache, sizeof(cache)) != 0) {
		di->cache = cache;
		power_supply_changed(di->bat);
	}

Otherwise that isn't an optimization, it probably takes more
time comparing than just doing the copy every time...

...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)
					

ACK

									Pavel