lkml.org 
[lkml]   [2017]   [Jul]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v3 2/2] thermal: uniphier: add UniPhier thermal driver
2017-07-05 20:50 GMT+09:00 Kunihiko Hayashi <hayashi.kunihiko@socionext.com>:

> +
> +#define TMOD 0x0928
> +#define TMOD_MASK GENMASK(9, 0)
> +
[ snip ]
> +
> + /*
> + * The bit[8:0] of TMOD register represents 2's complement value
> + * of temperature in Celsius. Since bit8 of TMOD shows a sign bit,
> + * 32bit temperature value is obtained by sign extension.
> + */


Apparently, this comment does not match your code:

#define TMOD_MASK GENMASK(9, 0)


TMOD_MASK is indicating bit[9:0].



Digging into the patch history, now I understood what happened.



In v1, you described
#define TMOD_MASK 0x1ff

This was correct.


In v2, you converted it into
#define TMOD_MASK GENMASK(9, 0)

This was misconversion. It should be GENMASK(8, 0)



Anyway, TMOD_MASK is not used any more.


> + *out_temp = sign_extend32(temp, 8) * 1000;


Why magic number here?

/* MSB of the TMOD field is a sign bit */
*out_temp = sign_extend32(temp, TMOD_WIDTH) * 1000;


--
Best Regards
Masahiro Yamada

\
 
 \ /
  Last update: 2017-07-05 14:21    [W:1.449 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site