[PATCH v3 2/2] thermal: uniphier: add UniPhier thermal driver
Masahiro Yamada
yamada.masahiro at socionext.com
Wed Jul 5 05:20:16 PDT 2017
2017-07-05 20:50 GMT+09:00 Kunihiko Hayashi <hayashi.kunihiko at 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
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