[PATCH 4/6] clk: Fix rate caching in clk_get_parent_rate()

[Samuel Holland]

clk_get_rate() can return an error value. Recompute the rate if the
cached value is an error value.

Fixes: 4aa78300a025 ("dm: clk: Define clk_get_parent_rate() for clk operations")
Signed-off-by: Samuel Holland <samuel at sholland.org>
---

 drivers/clk/clk-uclass.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/clk-uclass.c b/drivers/clk/clk-uclass.c
index 5bce976b060..9d052e5a814 100644
--- a/drivers/clk/clk-uclass.c
+++ b/drivers/clk/clk-uclass.c
@@ -520,7 +520,8 @@ ulong clk_get_parent_rate(struct clk *clk)
 		return -ENOSYS;
 
 	/* Read the 'rate' if not already set or if proper flag set*/
-	if (!pclk->rate || pclk->flags & CLK_GET_RATE_NOCACHE)
+	if (!pclk->rate || IS_ERR_VALUE(pclk->rate) ||
+	    pclk->flags & CLK_GET_RATE_NOCACHE)
 		pclk->rate = clk_get_rate(pclk);
 
 	return pclk->rate;
-- 
2.39.2