[PATCH v7 3/7] interconnect: Add of_icc_get_by_index() helper function

From: Georgi Djakov
Date: Fri Apr 24 2020 - 11:54:20 EST


This is the same as the traditional of_icc_get() function, but the
difference is that it takes index as an argument, instead of name.

Signed-off-by: Georgi Djakov <georgi.djakov@xxxxxxxxxx>
---
v7:
* Addressed review comments from Sibi.
* Re-based patch.

v2: https://lore.kernel.org/r/20190423132823.7915-3-georgi.djakov@xxxxxxxxxx

drivers/interconnect/core.c | 68 +++++++++++++++++++++++++++---------
include/linux/interconnect.h | 6 ++++
2 files changed, 58 insertions(+), 16 deletions(-)

diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c
index 2c6515e3ecf1..648237f4de49 100644
--- a/drivers/interconnect/core.c
+++ b/drivers/interconnect/core.c
@@ -351,9 +351,9 @@ static struct icc_node *of_icc_get_from_provider(struct of_phandle_args *spec)
}

/**
- * of_icc_get() - get a path handle from a DT node based on name
+ * of_icc_get_by_index() - get a path handle from a DT node based on index
* @dev: device pointer for the consumer device
- * @name: interconnect path name
+ * @idx: interconnect path index
*
* 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
@@ -365,13 +365,12 @@ static struct icc_node *of_icc_get_from_provider(struct of_phandle_args *spec)
* Return: icc_path pointer on success or ERR_PTR() on error. NULL is returned
* when the API is disabled or the "interconnects" DT property is missing.
*/
-struct icc_path *of_icc_get(struct device *dev, const char *name)
+struct icc_path *of_icc_get_by_index(struct device *dev, int idx)
{
struct icc_path *path = ERR_PTR(-EPROBE_DEFER);
struct icc_node *src_node, *dst_node;
struct device_node *np = NULL;
struct of_phandle_args src_args, dst_args;
- int idx = 0;
int ret;

if (!dev || !dev->of_node)
@@ -391,12 +390,6 @@ struct icc_path *of_icc_get(struct device *dev, const char *name)
* lets support only global ids and extend this in the future if needed
* without breaking DT compatibility.
*/
- if (name) {
- idx = of_property_match_string(np, "interconnect-names", name);
- if (idx < 0)
- return ERR_PTR(idx);
- }
-
ret = of_parse_phandle_with_args(np, "interconnects",
"#interconnect-cells", idx * 2,
&src_args);
@@ -439,12 +432,8 @@ struct icc_path *of_icc_get(struct device *dev, const char *name)
return path;
}

- if (name)
- path->name = kstrdup_const(name, GFP_KERNEL);
- else
- path->name = kasprintf(GFP_KERNEL, "%s-%s",
- src_node->name, dst_node->name);
-
+ path->name = kasprintf(GFP_KERNEL, "%s-%s",
+ src_node->name, dst_node->name);
if (!path->name) {
kfree(path);
return ERR_PTR(-ENOMEM);
@@ -452,6 +441,53 @@ struct icc_path *of_icc_get(struct device *dev, const char *name)

return path;
}
+EXPORT_SYMBOL_GPL(of_icc_get_by_index);
+
+/**
+ * of_icc_get() - get a path handle from a DT node based on name
+ * @dev: device pointer for the consumer device
+ * @name: interconnect path 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.
+ * If the interconnect API is disabled, NULL is returned and the consumer
+ * drivers will still build. Drivers are free to handle this specifically,
+ * but they don't have to.
+ *
+ * Return: icc_path pointer on success or ERR_PTR() on error. NULL is returned
+ * when the API is disabled or the "interconnects" DT property is missing.
+ */
+struct icc_path *of_icc_get(struct device *dev, const char *name)
+{
+ struct device_node *np = NULL;
+ int idx = 0;
+
+ if (!dev || !dev->of_node)
+ return ERR_PTR(-ENODEV);
+
+ np = dev->of_node;
+
+ /*
+ * When the consumer DT node do not have "interconnects" property
+ * return a NULL path to skip setting constraints.
+ */
+ if (!of_find_property(np, "interconnects", NULL))
+ return NULL;
+
+ /*
+ * We use a combination of phandle and specifier for endpoint. For now
+ * lets support only global ids and extend this in the future if needed
+ * without breaking DT compatibility.
+ */
+ if (name) {
+ idx = of_property_match_string(np, "interconnect-names", name);
+ if (idx < 0)
+ return ERR_PTR(idx);
+ }
+
+ return of_icc_get_by_index(dev, idx);
+}
EXPORT_SYMBOL_GPL(of_icc_get);

/**
diff --git a/include/linux/interconnect.h b/include/linux/interconnect.h
index d70a914cba11..34e97231a6ab 100644
--- a/include/linux/interconnect.h
+++ b/include/linux/interconnect.h
@@ -28,6 +28,7 @@ struct device;
struct icc_path *icc_get(struct device *dev, const int src_id,
const int dst_id);
struct icc_path *of_icc_get(struct device *dev, const char *name);
+struct icc_path *of_icc_get_by_index(struct device *dev, int idx);
void icc_put(struct icc_path *path);
int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw);
void icc_set_tag(struct icc_path *path, u32 tag);
@@ -46,6 +47,11 @@ static inline struct icc_path *of_icc_get(struct device *dev,
return NULL;
}

+static inline struct icc_path *of_icc_get_by_index(struct device *dev, int idx)
+{
+ return NULL;
+}
+
static inline void icc_put(struct icc_path *path)
{
}