interconnect: Reintroduce icc_get()

The original icc_get() that took integer node IDs was removed due to
lack of users. Reintroduce a new version that takes string node names,
which is needed for the debugfs client.

Signed-off-by: Mike Tipton <quic_mdtipton@quicinc.com>
Link: https://lore.kernel.org/r/20230807142914.12480-3-quic_mdtipton@quicinc.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>

diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c
index 5fac448..fc1461d 100644 (file)
--- a/drivers/interconnect/core.c
+++ b/drivers/interconnect/core.c
@@ -147,6 +147,21 @@ static struct icc_node *node_find(const int id)
        return idr_find(&icc_idr, id);
 }
 
+static struct icc_node *node_find_by_name(const char *name)
+{
+       struct icc_provider *provider;
+       struct icc_node *n;
+
+       list_for_each_entry(provider, &icc_providers, provider_list) {
+               list_for_each_entry(n, &provider->nodes, node_list) {
+                       if (!strcmp(n->name, name))
+                               return n;
+               }
+       }
+
+       return NULL;
+}
+
 static struct icc_path *path_init(struct device *dev, struct icc_node *dst,
                                  ssize_t num_nodes)
 {
@@ -562,6 +577,54 @@ struct icc_path *of_icc_get(struct device *dev, const char *name)
 EXPORT_SYMBOL_GPL(of_icc_get);
 
 /**
+ * icc_get() - get a path handle between two endpoints
+ * @dev: device pointer for the consumer device
+ * @src: source node name
+ * @dst: destination node name
+ *
+ * This function will search for a path between two endpoints and return an
+ * icc_path handle on success. Use icc_put() to release constraints when they
+ * are not needed anymore.
+ *
+ * Return: icc_path pointer on success or ERR_PTR() on error. NULL is returned
+ * when the API is disabled.
+ */
+struct icc_path *icc_get(struct device *dev, const char *src, const char *dst)
+{
+       struct icc_node *src_node, *dst_node;
+       struct icc_path *path = ERR_PTR(-EPROBE_DEFER);
+
+       mutex_lock(&icc_lock);
+
+       src_node = node_find_by_name(src);
+       if (!src_node) {
+               dev_err(dev, "%s: invalid src=%s\n", __func__, src);
+               goto out;
+       }
+
+       dst_node = node_find_by_name(dst);
+       if (!dst_node) {
+               dev_err(dev, "%s: invalid dst=%s\n", __func__, dst);
+               goto out;
+       }
+
+       path = path_find(dev, src_node, dst_node);
+       if (IS_ERR(path)) {
+               dev_err(dev, "%s: invalid path=%ld\n", __func__, PTR_ERR(path));
+               goto out;
+       }
+
+       path->name = kasprintf(GFP_KERNEL, "%s-%s", src_node->name, dst_node->name);
+       if (!path->name) {
+               kfree(path);
+               path = ERR_PTR(-ENOMEM);
+       }
+out:
+       mutex_unlock(&icc_lock);
+       return path;
+}
+
+/**
  * icc_set_tag() - set an optional tag on a path
  * @path: the path we want to tag
  * @tag: the tag value

diff --git a/drivers/interconnect/internal.h b/drivers/interconnect/internal.h
index f5f82a5..95d6ba2 100644 (file)
--- a/drivers/interconnect/internal.h
+++ b/drivers/interconnect/internal.h
@@ -41,4 +41,6 @@ struct icc_path {
        struct icc_req reqs[];
 };
 
+struct icc_path *icc_get(struct device *dev, const char *src, const char *dst);
+
 #endif