From c0a5f4a05af588a0f9951f8d24e2564b09501918 Mon Sep 17 00:00:00 2001 From: Rajkumar Kasirajan Date: Thu, 17 May 2012 17:03:24 -0700 Subject: drivers/rtc/rtc-pl031.c: configure correct wday for 2000-01-01 The reset date of the ST Micro version of PL031 is 2000-01-01. The correct weekday for 2000-01-01 is saturday, but pl031 is initialized to sunday. This may lead to alarm malfunction, so configure the correct wday if RTC_DR indicates reset. Signed-off-by: Rajkumar Kasirajan Signed-off-by: Linus Walleij Cc: Mattias Wallin Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-pl031.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/rtc/rtc-pl031.c b/drivers/rtc/rtc-pl031.c index 684ef4bbfce4..f027c063fb20 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) @@ -343,6 +344,23 @@ static int pl031_probe(struct amba_device *adev, const struct amba_id *id) 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)) { -- cgit v1.2.3