X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Frtc%2Frtc-pl031.c;h=1e80a48057e5dc58f7c219ac2e7d68cd9d06b96e;hb=21158e22d9a60b79f79d58b66b9909e06006d930;hp=ff1b84bd9bb56c81a55deb5f8b3ad3eb988fbbd0;hpb=93567c43eb2a4771b9c590435928f9b3a428e568;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/rtc/rtc-pl031.c b/drivers/rtc/rtc-pl031.c
index ff1b84bd9bb5..1e80a48057e5 100644
--- a/drivers/rtc/rtc-pl031.c
+++ b/drivers/rtc/rtc-pl031.c
@@ -312,6 +312,7 @@ static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
 	int ret;
 	struct pl031_local *ldata;
 	struct rtc_class_ops *ops = id->data;
+	unsigned long time;
 
 	ret = amba_request_regions(adev, NULL);
 	if (ret)
@@ -339,11 +340,27 @@ static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
 	dev_dbg(&adev->dev, "revision = 0x%01x\n", ldata->hw_revision);
 
 	/* Enable the clockwatch on ST Variants */
-	if ((ldata->hw_designer == AMBA_VENDOR_ST) &&
-	    (ldata->hw_revision > 1))
+	if (ldata->hw_designer == AMBA_VENDOR_ST)
 		writel(readl(ldata->base + RTC_CR) | RTC_CR_CWEN,
 		       ldata->base + RTC_CR);
 
+	/*
+	 * On ST PL031 variants, the RTC reset value does not provide correct
+	 * weekday for 2000-01-01. Correct the erroneous sunday to saturday.
+	 */
+	if (ldata->hw_designer == AMBA_VENDOR_ST) {
+		if (readl(ldata->base + RTC_YDR) == 0x2000) {
+			time = readl(ldata->base + RTC_DR);
+			if ((time &
+			     (RTC_MON_MASK | RTC_MDAY_MASK | RTC_WDAY_MASK))
+			    == 0x02120000) {
+				time = time | (0x7 << RTC_WDAY_SHIFT);
+				writel(0x2000, ldata->base + RTC_YLR);
+				writel(time, ldata->base + RTC_LR);
+			}
+		}
+	}
+
 	ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
 					THIS_MODULE);
 	if (IS_ERR(ldata->rtc)) {