Re: [PATCH 4/6] net: ethernet: ti: cpts: add ptp pps support

From: Jan Lübbe
Date: Wed Nov 30 2016 - 06:01:55 EST


On Mo, 2016-11-28 at 17:04 -0600, Grygorii Strashko wrote:
> --- a/Documentation/devicetree/bindings/net/keystone-netcp.txt
> +++ b/Documentation/devicetree/bindings/net/keystone-netcp.txt
> @@ -127,6 +127,16 @@ Optional properties:
> The number of external time stamp channels.
> The different CPTS versions might support up 8
> external time stamp channels. if absent - unsupported.
> + - cpts-ts-comp-length:
> + Enable time stamp comparison event and TS_COMP signal output
> + generation when CPTS counter reaches a value written to
> + the TS_COMP_VAL register.
> + The generated pulse width is 3 refclk cycles if this property
> + has no value (empty) or, otherwise, it should specify desired
> + pulse width in number of refclk periods - max value 2^16.
> + TS_COMP functionality will be disabled if not present.
> + - cpts-ts-comp-polarity-low:
> + Set polarity of TS_COMP signal to low. Default is hight.

Why is this configured via DT? Are the values fixed for a given board,
depending on external components? Couldn't this be configured somewhere
else?

Regards,
Jan
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |