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path: root/drivers/clk/clk.c
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-rw-r--r--drivers/clk/clk.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 9c9b28e5b30a..300fbdc973f5 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -637,6 +637,24 @@ static void clk_core_get_boundaries(struct clk_core *core,
*max_rate = min(*max_rate, clk_user->max_rate);
}
+static bool clk_core_check_boundaries(struct clk_core *core,
+ unsigned long min_rate,
+ unsigned long max_rate)
+{
+ struct clk *user;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (min_rate > core->max_rate || max_rate < core->min_rate)
+ return false;
+
+ hlist_for_each_entry(user, &core->clks, clks_node)
+ if (min_rate > user->max_rate || max_rate < user->min_rate)
+ return false;
+
+ return true;
+}
+
void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate,
unsigned long max_rate)
{
@@ -2306,6 +2324,11 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
clk->min_rate = min;
clk->max_rate = max;
+ if (!clk_core_check_boundaries(clk->core, min, max)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
rate = clk_core_get_rate_nolock(clk->core);
if (rate < min || rate > max) {
/*
@@ -2334,6 +2357,7 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
}
}
+out:
if (clk->exclusive_count)
clk_core_rate_protect(clk->core);
@@ -3314,6 +3338,19 @@ static void clk_core_reparent_orphans_nolock(void)
__clk_set_parent_after(orphan, parent, NULL);
__clk_recalc_accuracies(orphan);
__clk_recalc_rates(orphan, 0);
+
+ /*
+ * __clk_init_parent() will set the initial req_rate to
+ * 0 if the clock doesn't have clk_ops::recalc_rate and
+ * is an orphan when it's registered.
+ *
+ * 'req_rate' is used by clk_set_rate_range() and
+ * clk_put() to trigger a clk_set_rate() call whenever
+ * the boundaries are modified. Let's make sure
+ * 'req_rate' is set to something non-zero so that
+ * clk_set_rate_range() doesn't drop the frequency.
+ */
+ orphan->req_rate = orphan->rate;
}
}
}