2014-02-20 09:51:22

by Vikas Sajjan

[permalink] [raw]
Subject: [PATCH] rtc: rtc-s3c: Fix incorrect way of save/restore of S3C2410_TICNT for TYPE_S3C64XX

On exynos5250, exynos5420 and exynos5260 it was observed that, after 1 cycle
of S2R, the rtc-tick occurs at a very fast rate as compared to the rtc-tick
occuring before S2R.

This patch fixes the above issue by correcting the wrong way of save/restore
of S3C2410_TICNT for TYPE_S3C64XX.

Signed-off-by: Vikas Sajjan <[email protected]>
---
drivers/rtc/rtc-s3c.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index 7afd373..c4cde9c 100644
--- a/drivers/rtc/rtc-s3c.c
+++ b/drivers/rtc/rtc-s3c.c
@@ -580,10 +580,12 @@ static int s3c_rtc_suspend(struct device *dev)

clk_enable(rtc_clk);
/* save TICNT for anyone using periodic interrupts */
- ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON);
ticnt_en_save &= S3C64XX_RTCCON_TICEN;
+ ticnt_save = readl(s3c_rtc_base + S3C2410_TICNT);
+ } else {
+ ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
}
s3c_rtc_enable(pdev, 0);

@@ -605,10 +607,15 @@ static int s3c_rtc_resume(struct device *dev)

clk_enable(rtc_clk);
s3c_rtc_enable(pdev, 1);
- writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
- if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
- tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
- writew(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON);
+ if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
+ writel(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
+ if (ticnt_en_save) {
+ tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
+ writew(tmp | ticnt_en_save,
+ s3c_rtc_base + S3C2410_RTCCON);
+ }
+ } else {
+ writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
}

if (device_may_wakeup(dev) && wake_en) {
--
1.7.9.5