From fe0157ba679dc95407dd5eae6550a4ceaea75040 Mon Sep 17 00:00:00 2001 From: paulmn Date: Mon, 29 Aug 2022 14:46:39 +0200 Subject: rtc: pcf8523: fix for stop bit Bugfix for an issue detected when a goldcap capacitor gets fully discharged due to a long absence of the power supply, and then recharges again. The RTC failed to continue to keep the real-time clock. This was caused by the incorrect handling of the STOP bit in the RTC internal register. This fix solves the problem. Signed-off-by: paulmn Link: https://lore.kernel.org/r/20220829124639.10906-1-paulmn@axis.com Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-pcf8523.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) (limited to 'drivers/rtc/rtc-pcf8523.c') diff --git a/drivers/rtc/rtc-pcf8523.c b/drivers/rtc/rtc-pcf8523.c index 6174b3fd4b98..92de99f11a7a 100644 --- a/drivers/rtc/rtc-pcf8523.c +++ b/drivers/rtc/rtc-pcf8523.c @@ -99,24 +99,24 @@ static irqreturn_t pcf8523_irq(int irq, void *dev_id) static int pcf8523_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct pcf8523 *pcf8523 = dev_get_drvdata(dev); - u8 regs[7]; + u8 regs[10]; int err; - err = regmap_bulk_read(pcf8523->regmap, PCF8523_REG_SECONDS, regs, + err = regmap_bulk_read(pcf8523->regmap, PCF8523_REG_CONTROL1, regs, sizeof(regs)); if (err < 0) return err; - if (regs[0] & PCF8523_SECONDS_OS) + if ((regs[0] & PCF8523_CONTROL1_STOP) || (regs[3] & PCF8523_SECONDS_OS)) return -EINVAL; - tm->tm_sec = bcd2bin(regs[0] & 0x7f); - tm->tm_min = bcd2bin(regs[1] & 0x7f); - tm->tm_hour = bcd2bin(regs[2] & 0x3f); - tm->tm_mday = bcd2bin(regs[3] & 0x3f); - tm->tm_wday = regs[4] & 0x7; - tm->tm_mon = bcd2bin(regs[5] & 0x1f) - 1; - tm->tm_year = bcd2bin(regs[6]) + 100; + tm->tm_sec = bcd2bin(regs[3] & 0x7f); + tm->tm_min = bcd2bin(regs[4] & 0x7f); + tm->tm_hour = bcd2bin(regs[5] & 0x3f); + tm->tm_mday = bcd2bin(regs[6] & 0x3f); + tm->tm_wday = regs[7] & 0x7; + tm->tm_mon = bcd2bin(regs[8] & 0x1f) - 1; + tm->tm_year = bcd2bin(regs[9]) + 100; return 0; } -- cgit