While children of orphan clocks are not carried in the orphan-list itself,
they're nevertheless orphans in their own right as they also don't have an
input-rate available. To ease tracking if a clock is an orphan or has an
orphan in its parent path introduce an orphan field into struct clk and
update it and the fields in child-clocks when a clock gets added or removed
from the orphan-list.

Suggested-by: Stephen Boyd <sb...@codeaurora.org>
Signed-off-by: Heiko Stuebner <he...@sntech.de>
Cc: Boris Brezillon <boris.brezil...@free-electrons.com>
Cc: Alex Elder <el...@linaro.org>
Cc: Alexandre Belloni <alexandre.bell...@free-electrons.com>
Cc: Stephen Warren <swar...@wwwdotorg.org>
Cc: Max Filippov <jcmvb...@gmail.com>
Cc: ker...@pengutronix.de
Cc: Zhangfei Gao <zhangfei....@linaro.org>
Cc: Santosh Shilimkar <ssant...@kernel.org>
Cc: Chao Xie <chao....@marvell.com>
Cc: Jason Cooper <ja...@lakedaemon.net>
Cc: Stefan Wahren <stefan.wah...@i2se.com>
Cc: Andrew Bresticker <abres...@chromium.org>
Cc: Robert Jarzmik <robert.jarz...@free.fr>
Cc: Georgi Djakov <georgi.dja...@linaro.org>
Cc: Sylwester Nawrocki <s.nawro...@samsung.com>
Cc: Geert Uytterhoeven <geert+rene...@glider.be>
Cc: Barry Song <bao...@kernel.org>
Cc: Dinh Nguyen <dingu...@opensource.altera.com>
Cc: Viresh Kumar <viresh.li...@gmail.com>
Cc: Gabriel FERNANDEZ <gabriel.fernan...@st.com>
Cc: emi...@elopez.com.ar
Cc: Peter De Schrijver <pdeschrij...@nvidia.com>
Cc: Tero Kristo <t-kri...@ti.com>
Cc: Ulf Hansson <ulf.hans...@linaro.org>
Cc: Pawel Moll <pawel.m...@arm.com>
Cc: Michal Simek <michal.si...@xilinx.com>
---
 drivers/clk/clk.c | 33 ++++++++++++++++++++++++++++++---
 1 file changed, 30 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index b2361d4..341904f 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -62,6 +62,7 @@ struct clk_core {
        struct clk_core         *new_parent;
        struct clk_core         *new_child;
        unsigned long           flags;
+       bool                    orphan;
        unsigned int            enable_count;
        unsigned int            prepare_count;
        unsigned long           accuracy;
@@ -1401,18 +1402,40 @@ static int clk_fetch_parent_index(struct clk_core *clk,
        return -EINVAL;
 }
 
+/*
+ * Update the orphan status of @clk and all its children.
+ */
+static void clk_core_update_orphan_status(struct clk_core *clk, bool is_orphan)
+{
+       struct clk_core *child;
+
+       clk->orphan = is_orphan;
+
+       hlist_for_each_entry(child, &clk->children, child_node)
+               clk_core_update_orphan_status(child, is_orphan);
+}
+
 static void clk_reparent(struct clk_core *clk, struct clk_core *new_parent)
 {
+       bool was_orphan = clk->orphan;
+
        hlist_del(&clk->child_node);
 
        if (new_parent) {
+               bool becomes_orphan = new_parent->orphan;
+
                /* avoid duplicate POST_RATE_CHANGE notifications */
                if (new_parent->new_child == clk)
                        new_parent->new_child = NULL;
 
                hlist_add_head(&clk->child_node, &new_parent->children);
+
+               if (was_orphan != becomes_orphan)
+                       clk_core_update_orphan_status(clk, becomes_orphan);
        } else {
                hlist_add_head(&clk->child_node, &clk_orphan_list);
+               if (!was_orphan)
+                       clk_core_update_orphan_status(clk, true);
        }
 
        clk->parent = new_parent;
@@ -2302,13 +2325,17 @@ static int __clk_init(struct device *dev, struct clk 
*clk_user)
         * clocks and re-parent any that are children of the clock currently
         * being clk_init'd.
         */
-       if (clk->parent)
+       if (clk->parent) {
                hlist_add_head(&clk->child_node,
                                &clk->parent->children);
-       else if (clk->flags & CLK_IS_ROOT)
+               clk->orphan = clk->parent->orphan;
+       } else if (clk->flags & CLK_IS_ROOT) {
                hlist_add_head(&clk->child_node, &clk_root_list);
-       else
+               clk->orphan = false;
+       } else {
                hlist_add_head(&clk->child_node, &clk_orphan_list);
+               clk->orphan = true;
+       }
 
        /*
         * Set clk's accuracy.  The preferred method is to use
-- 
2.1.4

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