Re: [PATCH v2 net-next 1/2] net: dsa: Add support for devlink device parameters

[Andrew Lunn <andrew@lunn.ch>]

On Fri, Oct 04, 2019 at 08:21:22PM -0400, Vivien Didelot wrote:
> On Fri,  4 Oct 2019 23:09:33 +0200, Andrew Lunn <andrew@lunn.ch> wrote:
> > Add plumbing to allow DSA drivers to register parameters with devlink.
> > 
> > To keep with the abstraction, the DSA drivers pass the ds structure to
> > these helpers, and the DSA core then translates that to the devlink
> > structure associated to the device.
> > 
> > Signed-off-by: Andrew Lunn <andrew@lunn.ch>
> > ---
> >  include/net/dsa.h | 23 +++++++++++++++++++++++
> >  net/dsa/dsa.c     | 48 +++++++++++++++++++++++++++++++++++++++++++++++
> >  net/dsa/dsa2.c    |  7 ++++++-
> >  3 files changed, 77 insertions(+), 1 deletion(-)
> > 
> > diff --git a/include/net/dsa.h b/include/net/dsa.h
> > index 8c3ea0530f65..6623f4428930 100644
> > --- a/include/net/dsa.h
> > +++ b/include/net/dsa.h
> > @@ -541,6 +541,29 @@ struct dsa_switch_ops {
> >  	 */
> >  	netdev_tx_t (*port_deferred_xmit)(struct dsa_switch *ds, int port,
> >  					  struct sk_buff *skb);
> > +	/* Devlink parameters */
> > +	int	(*devlink_param_get)(struct dsa_switch *ds, u32 id,
> > +				     struct devlink_param_gset_ctx *ctx);
> > +	int	(*devlink_param_set)(struct dsa_switch *ds, u32 id,
> > +				     struct devlink_param_gset_ctx *ctx);
> 
> Unless that is how devlink is designed, shouldn't ctx be const on _set?

It is the way devlink is designed. The devlink structure is

truct devlink_param {
        u32 id;
        const char *name;
        bool generic;
        enum devlink_param_type type;
        unsigned long supported_cmodes;
        int (*get)(struct devlink *devlink, u32 id,
                   struct devlink_param_gset_ctx *ctx);
        int (*set)(struct devlink *devlink, u32 id,
                   struct devlink_param_gset_ctx *ctx);
        int (*validate)(struct devlink *devlink, u32 id,
                        union devlink_param_value val,
                        struct netlink_ext_ack *extack);
};

No const on set.

   Andrew