Re: [RFC PATCH 2/8] coresight: Fix remote endpoint parsing

[Suzuki K Poulose]

On 06/01/2018 08:46 PM, Mathieu Poirier wrote:
> On 1 June 2018 at 13:38, Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> wrote:
> > On Fri, Jun 01, 2018 at 02:16:01PM +0100, Suzuki K Poulose wrote:
> > > When parsing the remote endpoint of an output port, we do :
> > >       rport = of_graph_get_remote_port(ep);
> > >       rparent = of_graph_get_remote_port_parent(ep);
> > >
> > > and then parse the "remote_port" as if it was the remote endpoint,
> > > which is wrong. The code worked fine because we used endpoint number
> > > as the port number. Let us fix it and optimise a bit as:
> > >
> > >       remote_ep = of_graph_get_remote_endpoint(ep);
> > >       if (remote_ep)
> > >          remote_parent = of_graph_get_port_parent(remote_ep);
> > >
> > > and then, parse the remote_ep for the port/endpoint details.
> > >
> > > Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> > > Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> > > ---
> > >   drivers/hwtracing/coresight/of_coresight.c | 19 ++++++++++---------
> > >   1 file changed, 10 insertions(+), 9 deletions(-)
> > >
> > > diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
> > > index 7c37544..e0deab0 100644
> > > --- a/drivers/hwtracing/coresight/of_coresight.c
> > > +++ b/drivers/hwtracing/coresight/of_coresight.c
> > > @@ -128,7 +128,7 @@ of_get_coresight_platform_data(struct device *dev,
> > >        struct device *rdev;
> > >        struct device_node *ep = NULL;
> > >        struct device_node *rparent = NULL;
> > > -     struct device_node *rport = NULL;
> > > +     struct device_node *rep = NULL;
> > >
> > >        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> > >        if (!pdata)
> > > @@ -169,16 +169,17 @@ of_get_coresight_platform_data(struct device *dev,
> > >                        pdata->outports[i] = endpoint.port;
> > >
> > >                        /*
> > > -                      * Get a handle on the remote port and parent
> > > -                      * attached to it.
> > > +                      * Get a handle on the remote endpoint and the device
> > > +                      * it is attached to.
> > >                         */
> > > -                     rparent = of_graph_get_remote_port_parent(ep);
> > > -                     rport = of_graph_get_remote_port(ep);
> > > -
> > > -                     if (!rparent || !rport)
> > > +                     rep = of_graph_get_remote_endpoint(ep);
> > > +                     if (!rep)
> > > +                             continue;
> > > +                     rparent = of_graph_get_port_parent(rep);
> > > +                     if (!rparent)
> > >                                continue;
> > >
> > > -                     if (of_graph_parse_endpoint(rport, &rendpoint))
> > > +                     if (of_graph_parse_endpoint(rep, &rendpoint))
> > >                                continue;
> >
> > You are correct and I'm out to lunch.
> >
> > >                        rdev = of_coresight_get_endpoint_device(rparent);
> > > @@ -186,7 +187,7 @@ of_get_coresight_platform_data(struct device *dev,
> > >                                return ERR_PTR(-EPROBE_DEFER);
> > >
> > >                        pdata->child_names[i] = dev_name(rdev);
> > > -                     pdata->child_ports[i] = rendpoint.id;
> > > +                     pdata->child_ports[i] = rendpoint.port;
> >
> > You need to do a of_node_put() here for both rep and rparent.
>
> Same thing for the "continue" and error condition above.


Mathieu,

Thanks for pointing that out. I see that we were missing them for the
existing code as well. I will clean all this up.

Cheers
Suzuki