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From:   Min Li <min.li.xe@renesas.com>
To:     Jakub Kicinski <kuba@kernel.org>
CC:     "richardcochran@gmail.com" <richardcochran@gmail.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH net v2 2/2] ptp: idt82p33: implement double dco time
 correction
Thread-Topic: [PATCH net v2 2/2] ptp: idt82p33: implement double dco time
 correction
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Date:   Fri, 17 Sep 2021 20:19:08 +0000
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>=20
> > @@ -29,6 +29,14 @@ module_param(phase_snap_threshold, uint, 0);
> > MODULE_PARM_DESC(phase_snap_threshold,
> >  "threshold (1000ns by default) below which adjtime would ignore");
> >
> > +static bool delayed_accurate_adjtime =3D false;
> > +module_param(delayed_accurate_adjtime, bool, false);
> > +MODULE_PARM_DESC(delayed_accurate_adjtime,
> > +"set to true to use more accurate adjtime that is delayed to next
> > +1PPS signal");
>=20
> Module parameters are discouraged. If you have multiple devices on the
> system module parameters don't allow setting different options depending
> on device. Unless Richard or someone else suggests a better API for this
> please use something like devlink params instead (and remember to
> document them).
>=20
> > +static char *firmware;
> > +module_param(firmware, charp, 0);
>=20

Hi Jacob

Yes, this was suggested by Richard back then

On Fri, Jun 25, 2021 at 02:24:24PM +0000, Min Li wrote:
> How would you suggest to implement the change that make the new driver be=
havior optional?

I would say, module parameter or debugfs knob.

Thanks,
Richard

> What's the point of this? Just rename the file in the filesystem.

We use this parameter to specify firmware so that module can be autoloaded
/etc/modprobe.d/modname.conf