Re: [PATCH v2 11/13] clocksource: export the clocks_calc_mult_shift to use by timestamp code

From: Thomas Gleixner
Date: Tue Nov 29 2016 - 04:11:44 EST


On Mon, 28 Nov 2016, Grygorii Strashko wrote:

> From: Murali Karicheri <m-karicheri2@xxxxxx>
>
> The CPSW CPTS driver is capable of doing timestamping on tx/rx packets and
> requires to know mult and shift factors for timestamp conversion from raw
> value to nanoseconds (ptp clock). Now these mult and shift factors are
> calculated manually and provided through DT, which makes very hard to
> support of a lot number of platforms, especially if CPTS refclk is not the
> same for some kind of boards and depends on efuse settings (Keystone 2
> platforms). Hence, export clocks_calc_mult_shift() to allow drivers like
> CPSW CPTS (and other ptp drivesr) to benefit from automaitc calculation of
> mult and shift factors.
>
> Cc: John Stultz <john.stultz@xxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Signed-off-by: Murali Karicheri <m-karicheri2@xxxxxx>
> Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>

Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

> ---
> kernel/time/clocksource.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
> index 7e4fad7..150242c 100644
> --- a/kernel/time/clocksource.c
> +++ b/kernel/time/clocksource.c
> @@ -89,6 +89,7 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 maxsec)
> *mult = tmp;
> *shift = sft;
> }
> +EXPORT_SYMBOL_GPL(clocks_calc_mult_shift);
>
> /*[Clocksource internal variables]---------
> * curr_clocksource:
> --
> 2.10.1
>
>