[U-Boot] [PATCH v4 2/2] hwmon: do not init sensors on startup

Heiko Schocher hs at denx.de
Mon Aug 1 15:54:28 CEST 2011


Hello Wolfgang,

Wolfgang Denk wrote:
> Dear Heiko Schocher,
> 
> In message <1312196898-20228-1-git-send-email-hs at denx.de> you wrote:
>> The U-Boot Design Principles[1] clearly say:
>>
>>   Initialize devices only when they are needed within U-Boot, i.e. don't
>>   initialize the Ethernet interface(s) unless U-Boot performs a download
>>   over Ethernet; don't initialize any IDE or USB devices unless U-Boot
>>   actually tries to load files from these, etc. (and don't forget to
>>   shut down these devices after using them - otherwise nasty things may
>>   happen when you try to boot your OS).
>>
>> So, do not initialize and read the sensors on startup.
> ...
>> - changes since v3
>>   do not initialize static sensor_initialized with 0
> ...
>> +static unsigned long sensor_initialized = 0xffffffff;
> 
> Ummm.... no.  You failed to understand what the checkpatch error
> means.
> 
> There is no need to explicitly static variables with 0, because this
> is their default value if you leave them unitialized - unintialized
> data is allocated in the BSS segment, and thus get automatically
> initialized as 0.

Ah! Ok, I undo this change.

> The code above enforces allocation ion the data segment, i. e. it
> increses the (flash) memory footprint.
> 
> Please undo this.  Just omit the "= 0" par tin the declaration all
> together.

bye,
Heiko
-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany


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