linux-kernel - [PATCH] rtc: rv3028: correct weekday register usage

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Date:   Tue,  9 Mar 2021 14:47:19 +0100
From:   Heiko Schocher <hs@...x.de>
To:     linux-rtc@...r.kernel.org
Cc:     Heiko Schocher <hs@...x.de>,
        Alessandro Zummo <a.zummo@...ertech.it>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>,
        Teresa Remmet <t.remmet@...tec.de>,
        linux-kernel@...r.kernel.org
Subject: [PATCH] rtc: rv3028: correct weekday register usage

The datasheet for the rv3028 says the weekday has exact 3 bits
and in chapter 3.4.0 for the "3h–Weekday" register it says:
"""
This register holds the current day of the week. Each value represents
one weekday that is assigned by the user. Values will range from 0 to 6
The weekday counter is simply a 3-bit counter which counts up to 6
and then resets to 0.
"""

So do not code weekday bitwise instead, use the raw values from
0-6.

Tested on "PHYTEC phyBOARD-Pollux i.MX8MP" board.

Signed-off-by: Heiko Schocher <hs@...x.de>
---

 drivers/rtc/rtc-rv3028.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/rtc-rv3028.c b/drivers/rtc/rtc-rv3028.c
index 0c48d980d06ae..12c807306893f 100644
--- a/drivers/rtc/rtc-rv3028.c
+++ b/drivers/rtc/rtc-rv3028.c
@@ -320,7 +320,7 @@ static int rv3028_get_time(struct device *dev, struct rtc_time *tm)
 	tm->tm_sec  = bcd2bin(date[RV3028_SEC] & 0x7f);
 	tm->tm_min  = bcd2bin(date[RV3028_MIN] & 0x7f);
 	tm->tm_hour = bcd2bin(date[RV3028_HOUR] & 0x3f);
-	tm->tm_wday = ilog2(date[RV3028_WDAY] & 0x7f);
+	tm->tm_wday = date[RV3028_WDAY] & 0x7f;
 	tm->tm_mday = bcd2bin(date[RV3028_DAY] & 0x3f);
 	tm->tm_mon  = bcd2bin(date[RV3028_MONTH] & 0x1f) - 1;
 	tm->tm_year = bcd2bin(date[RV3028_YEAR]) + 100;
@@ -337,7 +337,7 @@ static int rv3028_set_time(struct device *dev, struct rtc_time *tm)
 	date[RV3028_SEC]   = bin2bcd(tm->tm_sec);
 	date[RV3028_MIN]   = bin2bcd(tm->tm_min);
 	date[RV3028_HOUR]  = bin2bcd(tm->tm_hour);
-	date[RV3028_WDAY]  = 1 << (tm->tm_wday);
+	date[RV3028_WDAY]  = tm->tm_wday;
 	date[RV3028_DAY]   = bin2bcd(tm->tm_mday);
 	date[RV3028_MONTH] = bin2bcd(tm->tm_mon + 1);
 	date[RV3028_YEAR]  = bin2bcd(tm->tm_year - 100);
-- 
2.29.2