[PATCH v2] clk: Dont return error when assigned-clocks is empty or missing

[Michal Simek]

From: Ashok Reddy Soma <ashok.reddy.soma at amd.com>

There is a chance that assigned-clock-rates is given and assigned-clocks
could be empty. Dont return error in that case, because the probe of the
corresponding driver will not be called at all if this fails.
Better to continue to look for it and return 0.

Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma at amd.com>
Signed-off-by: Michal Simek <michal.simek at amd.com>
Reviewed-by: Tom Rini <trini at konsulko.com>
---

Changes in v2:
- Add also test to cover it
- Add Tom's reviewed-by line

 arch/sandbox/dts/test.dts | 16 ++++++++++++++++
 drivers/clk/clk-uclass.c  |  8 +++++++-
 test/dm/clk.c             |  9 +++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index ff9f9222e6f9..90f876ac9c78 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -589,6 +589,22 @@
 		clock-names = "fixed", "i2c", "spi", "uart2", "uart1";
 	};
 
+	clk-test2 {
+		compatible = "sandbox,clk-test";
+		assigned-clock-rates = <321>;
+	};
+
+	clk-test3 {
+		compatible = "sandbox,clk-test";
+		assigned-clocks = <&clk_sandbox 1>;
+	};
+
+	clk-test4 {
+		compatible = "sandbox,clk-test";
+		assigned-clock-rates = <654>, <321>;
+		assigned-clocks = <&clk_sandbox 1>;
+	};
+
 	ccf: clk-ccf {
 		compatible = "sandbox,clk-ccf";
 	};
diff --git a/drivers/clk/clk-uclass.c b/drivers/clk/clk-uclass.c
index dc3e9d6a2615..f186fcbcdb86 100644
--- a/drivers/clk/clk-uclass.c
+++ b/drivers/clk/clk-uclass.c
@@ -329,7 +329,13 @@ static int clk_set_default_rates(struct udevice *dev,
 			dev_dbg(dev,
 				"could not get assigned clock %d (err = %d)\n",
 				index, ret);
-			continue;
+			/* Skip if it is empty */
+			if (ret == -ENOENT) {
+				ret = 0;
+				continue;
+			}
+
+			return ret;
 		}
 
 		/* This is clk provider device trying to program itself
diff --git a/test/dm/clk.c b/test/dm/clk.c
index f48de05436bf..01417fbd8257 100644
--- a/test/dm/clk.c
+++ b/test/dm/clk.c
@@ -36,6 +36,15 @@ static int dm_test_clk_base(struct unit_test_state *uts)
 	ut_asserteq(clk_is_match(&clk_method1, &clk_method2), true);
 	ut_asserteq(clk_method1.id, clk_method2.id);
 
+	ut_assertok(uclass_get_device_by_name(UCLASS_MISC, "clk-test2", &dev));
+	ut_assertok(clk_set_defaults(dev, CLK_DEFAULTS_PRE));
+
+	ut_assertok(uclass_get_device_by_name(UCLASS_MISC, "clk-test3", &dev));
+	ut_assertok(clk_set_defaults(dev, CLK_DEFAULTS_PRE));
+
+	ut_assertok(uclass_get_device_by_name(UCLASS_MISC, "clk-test4", &dev));
+	ut_assertok(clk_set_defaults(dev, CLK_DEFAULTS_PRE));
+
 	return 0;
 }
 
-- 
2.36.1