Re: [PATCH v8 5/8] Loongson: YeeLoong: add hardware monitoring driver

[Pavel Machek <pavel@ucw.cz>]

On Mon 2009-12-07 17:41:10, Wu Zhangjin wrote:
> On Mon, 2009-12-07 at 09:04 +0100, Pavel Machek wrote:
> > > > What is going on here? I thought the value is already in two's
> > > > complement... Is the above equivalent of
> > > > 
> > > > 	      if (value < 0)
> > > > 	      	 value = -value; 
> > > > 
> > > > ? If so, why? If not, can you add a comment?
> > > 
> > > Right, then, will use this instead:
> > > 
> > > static int get_battery_current(void)
> > > { 
> > > 	s16 value;
> > > 
> > > 	value = (ec_read(REG_BAT_CURRENT_HIGH) << 8) |
> > > 		(ec_read(REG_BAT_CURRENT_LOW));
> > > 
> > > 	return abs(value);
> > > }
> > 
> > That's certainly better. But... why not return signed value? Current
> > flowing from the battery is certainly very different from current
> > flowing into it...
> 
> You are totally right ;)
> 
> Just test it, when flowing from the battery, the value is negative, and
> when flowing into the battery, the value is positive, so, no abs()
> needed. thanks!

Make it return -value, then. I believe other code uses >0 values for
discharge.
									Pavel

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