[PATCH 1/4] mfd: ab8500: add devicetree support for fuelgauge

Rajanikanth HV rajanikanth.hv at stericsson.com
Thu Nov 15 06:34:58 EST 2012



On Saturday 10 November 2012 10:23 PM, Francesco Lavra wrote:
>>> I don't get the point of declaring the char array and copying the string
>>> in it, when you could simply use just the pointer returned by
>>> of_get_property().
>>
>> I am considering a corner case where in 'battery-type' property is not
>> present and battery is connected.In this case i promote battery to
>> UNKNOWN from null.
> 
> You could achieve the same result without using the char array, with
> this assignment:
> 
> btech = "UNKNOWN";
> 
>> FYI: Further, btemp driver will identify the connected battery based on
>> resistance value and decide to use.
>> Ref: ab8500_btemp_id(...) ab8500_btemp.c
>>
>>> Anyway, if the string property is longer than 8 characters, you are
>>> writing past the size of the destination array.
>>
>> i believe it is safe as power_supply.h comprises defines having battery
>> technology type in 4 characters length which is normally the case and
>> 7 chars length being "UNKNOWN" seldom referred
> 
> You should be able to handle whatever the device tree contains, and if
> it contains unexpected data this is not a good excuse for locking up the
> system.
agreed, if we were to go by what device tree contains then explicit
assignment for battery type as "UNKNOWN" is not required, hence only 2
use case persist as :
a) property name with one of the said value be present
	(as per documentation)
b) property name not present



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