linux-kernel - [PATCH 4/4] rtc: mcp795: use bcd2bin/bin2bcd.

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Date:   Mon,  5 Dec 2016 14:11:53 +0100
From:   Emil Bartczak <emilbart@...il.com>
To:     a.zummo@...ertech.it
Cc:     alexandre.belloni@...e-electrons.com, rtc-linux@...glegroups.com,
        linux-kernel@...r.kernel.org, Emil Bartczak <emilbart@...il.com>
Subject: [PATCH 4/4] rtc: mcp795: use bcd2bin/bin2bcd.

Change rtc-mcp795.c to use the bcd2bin/bin2bcd functions.
---
 drivers/rtc/rtc-mcp795.c | 28 +++++++++++++---------------
 1 file changed, 13 insertions(+), 15 deletions(-)

diff --git a/drivers/rtc/rtc-mcp795.c b/drivers/rtc/rtc-mcp795.c
index c9ad46c..1d823f9 100644
--- a/drivers/rtc/rtc-mcp795.c
+++ b/drivers/rtc/rtc-mcp795.c
@@ -22,6 +22,7 @@
 #include <linux/rtc.h>
 #include <linux/of.h>
 #include <linux/delay.h>
+#include <linux/bcd.h>
 
 /* MCP795 Instructions, see datasheet table 3-1 */
 #define MCP795_EEREAD		0x03
@@ -137,7 +138,6 @@ static int mcp795_start_oscillator(struct device *dev)
 
 static int mcp795_set_time(struct device *dev, struct rtc_time *tim)
 {
-	int month;
 	int ret;
 	u8 data[7];
 
@@ -152,10 +152,10 @@ static int mcp795_set_time(struct device *dev, struct rtc_time *tim)
 	if (ret)
 		return ret;
 
-	data[0] = (data[0] & 0x80) | ((tim->tm_sec / 10) << 4) | (tim->tm_sec % 10);
-	data[1] = (data[1] & 0x80) | ((tim->tm_min / 10) << 4) | (tim->tm_min % 10);
-	data[2] = ((tim->tm_hour / 10) << 4) | (tim->tm_hour % 10);
-	data[4] = ((tim->tm_mday / 10) << 4) | ((tim->tm_mday) % 10);
+	data[0] = (data[0] & 0x80) | bin2bcd(tim->tm_sec);
+	data[1] = (data[1] & 0x80) | bin2bcd(tim->tm_min);
+	data[2] = bin2bcd(tim->tm_hour);
+	data[4] = bin2bcd(tim->tm_mday);
 
 	/* Always write the date and month using a separate Write command.
 	 * This is a workaround for a know silicon issue that some combinations
@@ -166,14 +166,12 @@ static int mcp795_set_time(struct device *dev, struct rtc_time *tim)
 	if (ret)
 		return ret;
 
-	month = tim->tm_mon + 1;
-	data[5] = (data[5] & MCP795_LP_BIT) |
-			((month / 10) << 4) | (month % 10);
+	data[5] = (data[5] & MCP795_LP_BIT) | bin2bcd(tim->tm_mon + 1);
 
 	if (tim->tm_year > 100)
 		tim->tm_year -= 100;
 
-	data[6] = ((tim->tm_year / 10) << 4) | (tim->tm_year % 10);
+	data[6] = bin2bcd(tim->tm_year);
 
 	ret = mcp795_rtcc_write(dev, MCP795_REG_MONTH, &data[5], 2);
 
@@ -202,12 +200,12 @@ static int mcp795_read_time(struct device *dev, struct rtc_time *tim)
 	if (ret)
 		return ret;
 
-	tim->tm_sec	= ((data[0] & 0x70) >> 4) * 10 + (data[0] & 0x0f);
-	tim->tm_min	= ((data[1] & 0x70) >> 4) * 10 + (data[1] & 0x0f);
-	tim->tm_hour	= ((data[2] & 0x30) >> 4) * 10 + (data[2] & 0x0f);
-	tim->tm_mday	= ((data[4] & 0x30) >> 4) * 10 + (data[4] & 0x0f);
-	tim->tm_mon	= ((data[5] & 0x10) >> 4) * 10 + (data[5] & 0x0f) - 1;
-	tim->tm_year	= ((data[6] & 0xf0) >> 4) * 10 + (data[6] & 0x0f) + 100; /* Assume we are in 20xx */
+	tim->tm_sec	= bcd2bin(data[0] & 0x7F);
+	tim->tm_min	= bcd2bin(data[1] & 0x7F);
+	tim->tm_hour	= bcd2bin(data[2] & 0x3F);
+	tim->tm_mday	= bcd2bin(data[4] & 0x3F);
+	tim->tm_mon	= bcd2bin(data[5] & 0x1F) - 1;
+	tim->tm_year	= bcd2bin(data[6]) + 100; /* Assume we are in 20xx */
 
 	dev_dbg(dev, "Read from mcp795: %04d-%02d-%02d %02d:%02d:%02d\n",
 				tim->tm_year + 1900, tim->tm_mon, tim->tm_mday,
-- 
2.7.4