[PATCH 4/6] rtc: sun6i: Force the mux to the external oscillator

[Maxime Ripard]

The internal oscillator is way too inaccurate to do something useful with
it. Switch to the external oscillator if it is available.

Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
---
 drivers/rtc/rtc-sun6i.c | 12 ++++++++++++
 1 file changed, 12 insertions(+), 0 deletions(-)

diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c
index edd5627da10f..1695fae24cd5 100644
--- a/drivers/rtc/rtc-sun6i.c
+++ b/drivers/rtc/rtc-sun6i.c
@@ -493,6 +493,7 @@ static const struct rtc_class_ops sun6i_rtc_ops = {
 static int sun6i_rtc_probe(struct platform_device *pdev)
 {
 	struct sun6i_rtc_dev *chip = sun6i_rtc;
+	struct clk *parent;
 	int ret;
 
 	if (!chip)
@@ -540,6 +541,17 @@ static int sun6i_rtc_probe(struct platform_device *pdev)
 	/* disable alarm wakeup */
 	writel(0, chip->base + SUN6I_ALARM_CONFIG);
 
+	parent = clk_get(&pdev->dev, NULL);
+	if (!IS_ERR(parent)) {
+		ret = clk_set_parent(chip->losc, parent);
+		clk_put(parent);
+
+		if (ret) {
+			dev_err(&pdev->dev,
+				"Failed to reparent the RTC to the external oscillator\n");
+			return ret;
+		}
+	}
 	clk_prepare_enable(chip->losc);
 
 	chip->rtc = rtc_device_register("rtc-sun6i", &pdev->dev,
-- 
git-series 0.8.11