Set the OSC32K_SRC_SEL bit in the LOSC control register if a clock is
specified in the devicetree.
Signed-off-by: Mans Rullgard <mans@xxxxxxxxx>
---
The newer sun6i rtc driver is a proper clk provider with parent
selection. Doing the same thing in this driver would be difficult
while staying compatible with existing devicetrees. For that reason,
this simpler approach seems reasonable.
---
drivers/rtc/rtc-sunxi.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/rtc/rtc-sunxi.c b/drivers/rtc/rtc-sunxi.c
index 5d019e3a835a..4f1053eab778 100644
--- a/drivers/rtc/rtc-sunxi.c
+++ b/drivers/rtc/rtc-sunxi.c
@@ -5,6 +5,7 @@
* Copyright (c) 2013, Carlo Caione <carlo.caione@xxxxxxxxx>
*/
+#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/fs.h>
@@ -21,8 +22,10 @@
#include <linux/types.h>
#define SUNXI_LOSC_CTRL 0x0000
+#define SUNXI_LOSC_CTRL_KEY (0x16aa << 16)
#define SUNXI_LOSC_CTRL_RTC_HMS_ACC BIT(8)
#define SUNXI_LOSC_CTRL_RTC_YMD_ACC BIT(7)
+#define SUNXI_LOSC_CTRL_OSC32K_SRC_SEL BIT(0)
#define SUNXI_RTC_YMD 0x0004
@@ -422,6 +425,7 @@ MODULE_DEVICE_TABLE(of, sunxi_rtc_dt_ids);
static int sunxi_rtc_probe(struct platform_device *pdev)
{
struct sunxi_rtc_dev *chip;
+ struct clk *extclk;
int ret;
chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
@@ -455,6 +459,14 @@ static int sunxi_rtc_probe(struct platform_device *pdev)
return -ENODEV;
}
+ /* use external oscillator if present */
+ extclk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
+ if (IS_ERR(extclk))
+ return PTR_ERR(extclk);
+ if (extclk)
+ writel(SUNXI_LOSC_CTRL_KEY | SUNXI_LOSC_CTRL_OSC32K_SRC_SEL,
+ chip->base + SUNXI_LOSC_CTRL);
+
/* clear the alarm count value */
writel(0, chip->base + SUNXI_ALRM_DHMS);
--
2.41.0
