On 1 June 2018 at 13:38, Mathieu Poirier [off-list ref] wrote:

On Fri, Jun 01, 2018 at 02:16:01PM +0100, Suzuki K Poulose wrote:

quoted

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@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 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.

quoted

                      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.

quoted

                      i++;
              } while (ep);
--
2.7.4