clk: clock multiplexers may register out of order
When a clock, C is initialised any orphan clocks listing C as
a possible parent are reparented to it regardless of the
parent requested by the orphan's get_parent() operation.
This means that multiplexers registered before their parents
are reparented to the first parent subsequently declared,
regardless of the selection made by the hardware registers.
For example:
static const char *sel[] = { "srcA", "srcB", "dummy", "srcC" };
child = clk_register_mux(NULL, "child", sel, ARRAY_SIZE(sel), ...);
clk_register_fixed(NULL, "dummy", ...);
clk_register_fixed(NULL, "srcA", ...);
clk_register_fixed(NULL, "srcB", ...);
clk_register_fixed(NULL, "srcC", ...);
Causes child's parent to always be "dummy".
To fix this, when an orphanned clock has a get_parent() operation,
only reparent to the clock indicated by get_parent().
Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
[mturquette@linaro.org: improve $SUBJECT]
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 2fd28dd..9955ad7 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1298,12 +1298,20 @@
* walk the list of orphan clocks and reparent any that are children of
* this clock
*/
- hlist_for_each_entry_safe(orphan, tmp, tmp2, &clk_orphan_list, child_node)
+ hlist_for_each_entry_safe(orphan, tmp, tmp2, &clk_orphan_list, child_node) {
+ if (orphan->ops->get_parent) {
+ i = orphan->ops->get_parent(orphan->hw);
+ if (!strcmp(clk->name, orphan->parent_names[i]))
+ __clk_reparent(orphan, clk);
+ continue;
+ }
+
for (i = 0; i < orphan->num_parents; i++)
if (!strcmp(clk->name, orphan->parent_names[i])) {
__clk_reparent(orphan, clk);
break;
}
+ }
/*
* optional platform-specific magic