[PATCH v2 1/6] rtc: mcp795: use bcd2bin/bin2bcd.

From: Emil Bartczak
Date: Wed Dec 07 2016 - 18:27:54 EST


Change rtc-mcp795.c to use the bcd2bin/bin2bcd functions.
This change fixes the wrong conversion of month value
from binary to BCD (missing right shift operation for 10 month).

Signed-off-by: Emil Bartczak <emilbart@xxxxxxxxx>
---
drivers/rtc/rtc-mcp795.c | 25 +++++++++++++------------
1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/rtc/rtc-mcp795.c b/drivers/rtc/rtc-mcp795.c
index 4021fd0..0389ee0 100644
--- a/drivers/rtc/rtc-mcp795.c
+++ b/drivers/rtc/rtc-mcp795.c
@@ -21,6 +21,7 @@
#include <linux/spi/spi.h>
#include <linux/rtc.h>
#include <linux/of.h>
+#include <linux/bcd.h>

/* MCP795 Instructions, see datasheet table 3-1 */
#define MCP795_EEREAD 0x03
@@ -104,16 +105,16 @@ 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[5] = (data[5] & 0x10) | (tim->tm_mon / 10) | (tim->tm_mon % 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);
+ data[5] = (data[5] & 0x10) | bin2bcd(tim->tm_mon);

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, 0x01, data, sizeof(data));

@@ -137,12 +138,12 @@ 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);
- 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);
+ 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