Re: [Patch] acerhdf: Return temperature in milidegree

[Peter Feuerer <peter@piie.net>]

Hi Andreas,

thank you very much for your brainstorming.

Andreas Mohr writes:

> Hi,
> 
> On Mon, Oct 19, 2009 at 10:21:16AM +0200, Peter Feuerer wrote:
>> 
>> Hi Boris,
>> 
>> what do you think about this patch?
> 
> Personally I'm hurting a bit due to the open-coded "* 1000" transition
> in all places.
> 
> I'd add a helper macro
> #define TEMP_DEGREE_TO_SYS(x) ((x) * 1000)
> and use that in all places where it matters.
> 
> Advantage:
> - either no mistyping (10000 instead of 1000) _or_ bug occurring in _all_
>   places where this macro is used
> - easily grepped-for
> - easily changed once the system granularity gets updated

I agree with you in these points, but I have also some disadvantages to discuss:

Disadvantages:
 - Thinking about the implemenation such a macro would require, users may 
   get confused. They would still set the fanon / fanoff trip points in 
   degree, but when they read documentation or the current temperature, 
   millidegree is used.  
 - I think "TEMP_DEGREE_TO_SYS(59)" in code is not 
   as good readable as "59000"

what about writing something like "59 * 1000" insead of "59000"?

Or something like that:

#define FACTOR_MILLIDEGREE 1000
59 * FACTOR_MILLIDEGREE 

this solution has all your listed advantages and eliminates the 
disadvantages I see in the "TEMP_DEGREE_TO_SYS" solution.

--peter