coresight: adding sink parameter to function coresight_build_path()

[firefly-linux-kernel-4.4.55.git] / drivers / hwtracing / coresight / coresight.c

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index d08d1ab9bba5d7e1c0772d48b6d43802057e323d..508532b3fcac74f2d6dc5593fc5d20fb7944d8f7 100644 (file)
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -371,31 +371,42 @@ struct coresight_device *coresight_get_sink(struct list_head *path)
 /**
  * _coresight_build_path - recursively build a path from a @csdev to a sink.
  * @csdev:     The device to start from.
+ * @sink:      The name of the sink this path should connect with.
  * @path:      The list to add devices to.
  *
- * The tree of Coresight device is traversed until an activated sink is
- * found.  From there the sink is added to the list along with all the
- * devices that led to that point - the end result is a list from source
- * to sink. In that list the source is the first device and the sink the
- * last one.
+ * The tree of Coresight device is traversed until an activated sink or
+ * the one specified by @sink is found.
+ * From there the sink is added to the list along with all the devices that
+ * led to that point - the end result is a list from source to sink. In that
+ * list the source is the first device and the sink the last one.
  */
 static int _coresight_build_path(struct coresight_device *csdev,
-                                struct list_head *path)
+                                const char *sink, struct list_head *path)
 {
        int i;
        bool found = false;
        struct coresight_node *node;
 
-       /* An activated sink has been found.  Enqueue the element */
-       if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
-            csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) && csdev->activated)
-               goto out;
+       /*
+        * First see if we are dealing with a sink.  If we have one check if
+        * it was selected via sysFS or the perf cmd line.
+        */
+       if (csdev->type == CORESIGHT_DEV_TYPE_SINK ||
+           csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) {
+               /* Activated via perf cmd line */
+               if (sink && !strcmp(dev_name(&csdev->dev), sink))
+                       goto out;
+               /* Activatred via sysFS */
+               if (csdev->activated)
+                       goto out;
+       }
 
        /* Not a sink - recursively explore each port found on this element */
        for (i = 0; i < csdev->nr_outport; i++) {
                struct coresight_device *child_dev = csdev->conns[i].child_dev;
 
-               if (child_dev && _coresight_build_path(child_dev, path) == 0) {
+               if (child_dev &&
+                   _coresight_build_path(child_dev, sink, path) == 0) {
                        found = true;
                        break;
                }
@@ -422,7 +433,8 @@ out:
        return 0;
 }
 
-struct list_head *coresight_build_path(struct coresight_device *csdev)
+struct list_head *coresight_build_path(struct coresight_device *csdev,
+                                      const char *sink)
 {
        struct list_head *path;
        int rc;
@@ -433,7 +445,7 @@ struct list_head *coresight_build_path(struct coresight_device *csdev)
 
        INIT_LIST_HEAD(path);
 
-       rc = _coresight_build_path(csdev, path);
+       rc = _coresight_build_path(csdev, sink, path);
        if (rc) {
                kfree(path);
                return ERR_PTR(rc);
@@ -508,7 +520,7 @@ int coresight_enable(struct coresight_device *csdev)
        if (csdev->enable)
                goto out;
 
-       path = coresight_build_path(csdev);
+       path = coresight_build_path(csdev, NULL);
        if (IS_ERR(path)) {
                pr_err("building path(s) failed\n");
                ret = PTR_ERR(path);