[PATCH] opp: Expose bandwidth information via debugfs

[Viresh Kumar]

Expose the bandwidth information as well via debugfs.

Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Georgi Djakov <georgi.djakov@xxxxxxxxxx>
---
@Georgi: I am applying this along with your series.

 drivers/interconnect/core.c  | 18 ++++++++++++++++
 drivers/opp/debugfs.c        | 42 ++++++++++++++++++++++++++++++++++++
 include/linux/interconnect.h |  6 ++++++
 3 files changed, 66 insertions(+)

diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c
index 2d2e49780511..a56349c14985 100644
--- a/drivers/interconnect/core.c
+++ b/drivers/interconnect/core.c
@@ -514,6 +514,24 @@ void icc_set_tag(struct icc_path *path, u32 tag)
 }
 EXPORT_SYMBOL_GPL(icc_set_tag);
 
+/**
+ * icc_get_name() - Get name of the icc path
+ * @path: reference to the path returned by icc_get()
+ *
+ * This function is used by an interconnect consumer to get the name of the icc
+ * path.
+ *
+ * Returns a valid pointer on success, or NULL otherwise.
+ */
+const char *icc_get_name(struct icc_path *path)
+{
+	if (!path)
+		return NULL;
+
+	return path->name;
+}
+EXPORT_SYMBOL_GPL(icc_get_name);
+
 /**
  * icc_set_bw() - set bandwidth constraints on an interconnect path
  * @path: reference to the path returned by icc_get()
diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
index 609665e339b6..596c185b5dda 100644
--- a/drivers/opp/debugfs.c
+++ b/drivers/opp/debugfs.c
@@ -32,6 +32,47 @@ void opp_debug_remove_one(struct dev_pm_opp *opp)
 	debugfs_remove_recursive(opp->dentry);
 }
 
+static ssize_t bw_name_read(struct file *fp, char __user *userbuf,
+			    size_t count, loff_t *ppos)
+{
+	struct icc_path *path = fp->private_data;
+	char buf[64];
+	int i;
+
+	i = scnprintf(buf, sizeof(buf), "%.62s\n", icc_get_name(path));
+
+	return simple_read_from_buffer(userbuf, count, ppos, buf, i);
+}
+
+static const struct file_operations bw_name_fops = {
+	.open = simple_open,
+	.read = bw_name_read,
+	.llseek = default_llseek,
+};
+
+static void opp_debug_create_bw(struct dev_pm_opp *opp,
+				struct opp_table *opp_table,
+				struct dentry *pdentry)
+{
+	struct dentry *d;
+	char name[11];
+	int i;
+
+	for (i = 0; i < opp_table->path_count; i++) {
+		snprintf(name, sizeof(name), "icc-path-%.1d", i);
+
+		/* Create per-path directory */
+		d = debugfs_create_dir(name, pdentry);
+
+		debugfs_create_file("name", S_IRUGO, d, opp_table->paths[i],
+				    &bw_name_fops);
+		debugfs_create_u32("peak_bw", S_IRUGO, d,
+				   &opp->bandwidth[i].peak);
+		debugfs_create_u32("avg_bw", S_IRUGO, d,
+				   &opp->bandwidth[i].avg);
+	}
+}
+
 static void opp_debug_create_supplies(struct dev_pm_opp *opp,
 				      struct opp_table *opp_table,
 				      struct dentry *pdentry)
@@ -94,6 +135,7 @@ void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
 			     &opp->clock_latency_ns);
 
 	opp_debug_create_supplies(opp, opp_table, d);
+	opp_debug_create_bw(opp, opp_table, d);
 
 	opp->dentry = d;
 }
diff --git a/include/linux/interconnect.h b/include/linux/interconnect.h
index 34e97231a6ab..1ad09efd296e 100644
--- a/include/linux/interconnect.h
+++ b/include/linux/interconnect.h
@@ -32,6 +32,7 @@ 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);
+const char *icc_get_name(struct icc_path *path);
 
 #else
 
@@ -65,6 +66,11 @@ static inline void icc_set_tag(struct icc_path *path, u32 tag)
 {
 }
 
+static inline const char *icc_get_name(struct icc_path *path)
+{
+	return NULL;
+}
+
 #endif /* CONFIG_INTERCONNECT */
 
 #endif /* __LINUX_INTERCONNECT_H */
-- 
2.25.0.rc1.19.g042ed3e048af