u-boot fix to charge empty battery

[Philipp Hug]

> I linked this to the LED just for convenience. In theory, you could
> probably make the non-charging interval much shorter.
>
> You need to stop the charger when measuring, because a battery that's
> missing or in cut-off would read as being at the float voltage (i.e.,
> full) otherwise.
>
>   
Can't this be detected otherwise? I just found out that the battery
present check is wrong as it only checks if battery voltage is higher
than bvmlvl in the BVMCTL register.

>> * revisions <6 don't blink the LED when charging, this isn't optimal,  
>> because can't see the difference between being switched off and charging  
>> silently.
>>     
>
> Yeah, I didn't enjoy doing that. You could probably get away by
> briefly flashing the LED, and living on the extra juice stored in
> capacitors. Not sure if it's worth the trouble, though.
>
>   
>> Does anyone know how much current the LED use on GTA02v5?
>>     
>
> About 50mA, half of the total current budget in that situation.
>   
probably too much.
thanks
philipp