[PATCH v2 10/11] clk: fix CLK_SET_RATE_GATE with clock rate protection

Jerome Brunet jbrunet at baylibre.com
Sun May 21 14:59:57 PDT 2017


Using clock rate protection, we can now enforce CLK_SET_RATE_GATE along the
clock tree

Signed-off-by: Jerome Brunet <jbrunet at baylibre.com>
---
 drivers/clk/clk.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 01306191133c..6ee5fc59cf1f 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -491,6 +491,9 @@ static void clk_core_unprepare(struct clk_core *core)
 	if (WARN_ON(core->prepare_count == 1 && core->flags & CLK_IS_CRITICAL))
 		return;
 
+	if (core->flags & CLK_SET_RATE_GATE)
+		clk_core_rate_unprotect(core);
+
 	if (--core->prepare_count > 0)
 		return;
 
@@ -561,6 +564,14 @@ static int clk_core_prepare(struct clk_core *core)
 
 	core->prepare_count++;
 
+	/*
+	 * CLK_SET_RATE_GATE is a special case of clock protection
+	 * Instead of a consumer protection, the provider is protecting
+	 * itself when prepared
+	 */
+	if (core->flags & CLK_SET_RATE_GATE)
+		clk_core_rate_protect(core);
+
 	return 0;
 }
 
@@ -1738,9 +1749,6 @@ static int clk_core_set_rate_nolock(struct clk_core *core,
 	if (clk_core_rate_is_protected(core))
 		return -EBUSY;
 
-	if ((core->flags & CLK_SET_RATE_GATE) && core->prepare_count)
-		return -EBUSY;
-
 	/* calculate new rates and get the topmost changed clock */
 	top = clk_calc_new_rates(core, req_rate);
 	if (!top)
-- 
2.9.4




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