clk: flatten clk tree in debugfs

This patch flattens the clk tree in CCF debugfs. Instead of representing the
clocks and their hierarchy as a directory structure under
/sys/kernel/debug/clk, each clock gets a single directory directly under
/sys/kernel/debug/clk. The orphans directory is replaced by a file called
clk_orphan_summary.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

1 files changed, 35 insertions, 79 deletions

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 8b73edef151d..7dfb2f308b35 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -36,6 +36,17 @@ static HLIST_HEAD(clk_root_list);
 static HLIST_HEAD(clk_orphan_list);
 static LIST_HEAD(clk_notifier_list);
 
+static struct hlist_head *all_lists[] = {
+        &clk_root_list,
+        &clk_orphan_list,
+        NULL,
+};
+
+static struct hlist_head *orphan_list[] = {
+        &clk_orphan_list,
+        NULL,
+};
+
 /***           locking             ***/
 static void clk_prepare_lock(void)
 {
@@ -98,7 +109,6 @@ static void clk_enable_unlock(unsigned long flags)
 #include <linux/debugfs.h>
 
 static struct dentry *rootdir;
-static struct dentry *orphandir;
 static int inited = 0;
 
 static void clk_summary_show_one(struct seq_file *s, struct clk *c, int level)
@@ -130,17 +140,16 @@ static void clk_summary_show_subtree(struct seq_file *s, struct clk *c,
 static int clk_summary_show(struct seq_file *s, void *data)
 {
         struct clk *c;
+        struct hlist_head **lists = (struct hlist_head **)s->private;
 
         seq_puts(s, "   clock                         enable_cnt  prepare_cnt        rate   accuracy\n");
         seq_puts(s, "--------------------------------------------------------------------------------\n");
 
         clk_prepare_lock();
 
-        hlist_for_each_entry(c, &clk_root_list, child_node)
-                clk_summary_show_subtree(s, c, 0);
-
-        hlist_for_each_entry(c, &clk_orphan_list, child_node)
-                clk_summary_show_subtree(s, c, 0);
+        for (; *lists; lists++)
+                hlist_for_each_entry(c, *lists, child_node)
+                        clk_summary_show_subtree(s, c, 0);
 
         clk_prepare_unlock();
 
@@ -193,21 +202,19 @@ static int clk_dump(struct seq_file *s, void *data)
 {
         struct clk *c;
         bool first_node = true;
+        struct hlist_head **lists = (struct hlist_head **)s->private;
 
         seq_printf(s, "{");
 
         clk_prepare_lock();
 
-        hlist_for_each_entry(c, &clk_root_list, child_node) {
-                if (!first_node)
-                        seq_printf(s, ",");
-                first_node = false;
-                clk_dump_subtree(s, c, 0);
-        }
-
-        hlist_for_each_entry(c, &clk_orphan_list, child_node) {
-                seq_printf(s, ",");
-                clk_dump_subtree(s, c, 0);
+        for (; *lists; lists++) {
+                hlist_for_each_entry(c, *lists, child_node) {
+                        if (!first_node)
+                                seq_puts(s, ",");
+                        first_node = false;
+                        clk_dump_subtree(s, c, 0);
+                }
         }
 
         clk_prepare_unlock();
@@ -305,7 +312,7 @@ static int clk_debug_create_subtree(struct clk *clk, struct dentry *pdentry)
                 goto out;
 
         hlist_for_each_entry(child, &clk->children, child_node)
-                clk_debug_create_subtree(child, clk->dentry);
+                clk_debug_create_subtree(child, pdentry);
 
         ret = 0;
 out:
@@ -325,31 +332,12 @@ out:
  */
 static int clk_debug_register(struct clk *clk)
 {
-        struct clk *parent;
-        struct dentry *pdentry;
         int ret = 0;
 
         if (!inited)
                 goto out;
 
-        parent = clk->parent;
-
-        /*
-         * Check to see if a clk is a root clk.  Also check that it is
-         * safe to add this clk to debugfs
-         */
-        if (!parent)
-                if (clk->flags & CLK_IS_ROOT)
-                        pdentry = rootdir;
-                else
-                        pdentry = orphandir;
-        else
-                if (parent->dentry)
-                        pdentry = parent->dentry;
-                else
-                        goto out;
-
-        ret = clk_debug_create_subtree(clk, pdentry);
+        ret = clk_debug_create_subtree(clk, rootdir);
 
 out:
         return ret;
@@ -371,39 +359,6 @@ static void clk_debug_unregister(struct clk *clk)
 }
 
 /**
- * clk_debug_reparent - reparent clk node in the debugfs clk tree
- * @clk: the clk being reparented
- * @new_parent: the new clk parent, may be NULL
- *
- * Rename clk entry in the debugfs clk tree if debugfs has been
- * initialized.  Otherwise it bails out early since the debugfs clk tree
- * will be created lazily by clk_debug_init as part of a late_initcall.
- *
- * Caller must hold prepare_lock.
- */
-static void clk_debug_reparent(struct clk *clk, struct clk *new_parent)
-{
-        struct dentry *d;
-        struct dentry *new_parent_d;
-
-        if (!inited)
-                return;
-
-        if (new_parent)
-                new_parent_d = new_parent->dentry;
-        else
-                new_parent_d = orphandir;
-
-        d = debugfs_rename(clk->dentry->d_parent, clk->dentry,
-                        new_parent_d, clk->name);
-        if (d)
-                clk->dentry = d;
-        else
-                pr_debug("%s: failed to rename debugfs entry for %s\n",
-                                __func__, clk->name);
-}
-
-/**
  * clk_debug_init - lazily create the debugfs clk tree visualization
  *
  * clks are often initialized very early during boot before memory can
@@ -425,19 +380,24 @@ static int __init clk_debug_init(void)
         if (!rootdir)
                 return -ENOMEM;
 
-        d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, NULL,
+        d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, &all_lists,
                                 &clk_summary_fops);
         if (!d)
                 return -ENOMEM;
 
-        d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, NULL,
+        d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, &all_lists,
                                 &clk_dump_fops);
         if (!d)
                 return -ENOMEM;
 
-        orphandir = debugfs_create_dir("orphans", rootdir);
+        d = debugfs_create_file("clk_orphan_summary", S_IRUGO, rootdir,
+                                &orphan_list, &clk_summary_fops);
+        if (!d)
+                return -ENOMEM;
 
-        if (!orphandir)
+        d = debugfs_create_file("clk_orphan_dump", S_IRUGO, rootdir,
+                                &orphan_list, &clk_dump_fops);
+        if (!d)
                 return -ENOMEM;
 
         clk_prepare_lock();
@@ -446,7 +406,7 @@ static int __init clk_debug_init(void)
                 clk_debug_create_subtree(clk, rootdir);
 
         hlist_for_each_entry(clk, &clk_orphan_list, child_node)
-                clk_debug_create_subtree(clk, orphandir);
+                clk_debug_create_subtree(clk, rootdir);
 
         inited = 1;
 
@@ -1284,9 +1244,6 @@ static void __clk_set_parent_after(struct clk *clk, struct clk *parent,
                 clk_disable(old_parent);
                 __clk_unprepare(old_parent);
         }
-
-        /* update debugfs with new clk tree topology */
-        clk_debug_reparent(clk, parent);
 }
 
 static int __clk_set_parent(struct clk *clk, struct clk *parent, u8 p_index)
@@ -1683,7 +1640,6 @@ out:
 void __clk_reparent(struct clk *clk, struct clk *new_parent)
 {
         clk_reparent(clk, new_parent);
-        clk_debug_reparent(clk, new_parent);
         __clk_recalc_accuracies(clk);
         __clk_recalc_rates(clk, POST_RATE_CHANGE);
 }