[RFC PATCH v2 4/9] rtc/ab3100: Update driver to address y2038/y2106 issues

From: Xunlei Pang
Date: Tue Jan 13 2015 - 10:52:00 EST


From: Xunlei Pang <pang.xunlei@xxxxxxxxxx>

This driver has a number of y2038/y2106 issues.

This patch resolves them by:
- Replace rtc_tm_to_time() with rtc_tm_to_time64()
- Replace rtc_time_to_tm() with rtc_time64_to_tm()
- Change ab3100_rtc_set_mmss() to use rtc_class_ops's set_mmss64()

After this patch, the driver should not have any remaining
y2038/y2106 issues.

Signed-off-by: Xunlei Pang <pang.xunlei@xxxxxxxxxx>
---
drivers/rtc/rtc-ab3100.c | 55 ++++++++++++++++++++++++------------------------
1 file changed, 27 insertions(+), 28 deletions(-)

diff --git a/drivers/rtc/rtc-ab3100.c b/drivers/rtc/rtc-ab3100.c
index 1d0340f..9b725c5 100644
--- a/drivers/rtc/rtc-ab3100.c
+++ b/drivers/rtc/rtc-ab3100.c
@@ -43,21 +43,21 @@
/*
* RTC clock functions and device struct declaration
*/
-static int ab3100_rtc_set_mmss(struct device *dev, unsigned long secs)
+static int ab3100_rtc_set_mmss(struct device *dev, time64_t secs)
{
u8 regs[] = {AB3100_TI0, AB3100_TI1, AB3100_TI2,
AB3100_TI3, AB3100_TI4, AB3100_TI5};
unsigned char buf[6];
- u64 fat_time = (u64) secs * AB3100_RTC_CLOCK_RATE * 2;
+ u64 hw_counter = secs * AB3100_RTC_CLOCK_RATE * 2;
int err = 0;
int i;

- buf[0] = (fat_time) & 0xFF;
- buf[1] = (fat_time >> 8) & 0xFF;
- buf[2] = (fat_time >> 16) & 0xFF;
- buf[3] = (fat_time >> 24) & 0xFF;
- buf[4] = (fat_time >> 32) & 0xFF;
- buf[5] = (fat_time >> 40) & 0xFF;
+ buf[0] = (hw_counter) & 0xFF;
+ buf[1] = (hw_counter >> 8) & 0xFF;
+ buf[2] = (hw_counter >> 16) & 0xFF;
+ buf[3] = (hw_counter >> 24) & 0xFF;
+ buf[4] = (hw_counter >> 32) & 0xFF;
+ buf[5] = (hw_counter >> 40) & 0xFF;

for (i = 0; i < 6; i++) {
err = abx500_set_register_interruptible(dev, 0,
@@ -75,7 +75,7 @@ static int ab3100_rtc_set_mmss(struct device *dev, unsigned long secs)

static int ab3100_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
- unsigned long time;
+ time64_t time;
u8 rtcval;
int err;

@@ -88,7 +88,7 @@ static int ab3100_rtc_read_time(struct device *dev, struct rtc_time *tm)
dev_info(dev, "clock not set (lost power)");
return -EINVAL;
} else {
- u64 fat_time;
+ u64 hw_counter;
u8 buf[6];

/* Read out time registers */
@@ -98,22 +98,21 @@ static int ab3100_rtc_read_time(struct device *dev, struct rtc_time *tm)
if (err != 0)
return err;

- fat_time = ((u64) buf[5] << 40) | ((u64) buf[4] << 32) |
+ hw_counter = ((u64) buf[5] << 40) | ((u64) buf[4] << 32) |
((u64) buf[3] << 24) | ((u64) buf[2] << 16) |
((u64) buf[1] << 8) | (u64) buf[0];
- time = (unsigned long) (fat_time /
- (u64) (AB3100_RTC_CLOCK_RATE * 2));
+ time = hw_counter / (u64) (AB3100_RTC_CLOCK_RATE * 2);
}

- rtc_time_to_tm(time, tm);
+ rtc_time64_to_tm(time, tm);

return rtc_valid_tm(tm);
}

static int ab3100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
- unsigned long time;
- u64 fat_time;
+ time64_t time;
+ u64 hw_counter;
u8 buf[6];
u8 rtcval;
int err;
@@ -134,11 +133,11 @@ static int ab3100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
AB3100_AL0, buf, 4);
if (err)
return err;
- fat_time = ((u64) buf[3] << 40) | ((u64) buf[2] << 32) |
+ hw_counter = ((u64) buf[3] << 40) | ((u64) buf[2] << 32) |
((u64) buf[1] << 24) | ((u64) buf[0] << 16);
- time = (unsigned long) (fat_time / (u64) (AB3100_RTC_CLOCK_RATE * 2));
+ time = hw_counter / (u64) (AB3100_RTC_CLOCK_RATE * 2);

- rtc_time_to_tm(time, &alarm->time);
+ rtc_time64_to_tm(time, &alarm->time);

return rtc_valid_tm(&alarm->time);
}
@@ -147,17 +146,17 @@ static int ab3100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
u8 regs[] = {AB3100_AL0, AB3100_AL1, AB3100_AL2, AB3100_AL3};
unsigned char buf[4];
- unsigned long secs;
- u64 fat_time;
+ time64_t secs;
+ u64 hw_counter;
int err;
int i;

- rtc_tm_to_time(&alarm->time, &secs);
- fat_time = (u64) secs * AB3100_RTC_CLOCK_RATE * 2;
- buf[0] = (fat_time >> 16) & 0xFF;
- buf[1] = (fat_time >> 24) & 0xFF;
- buf[2] = (fat_time >> 32) & 0xFF;
- buf[3] = (fat_time >> 40) & 0xFF;
+ secs = rtc_tm_to_time64(&alarm->time);
+ hw_counter = secs * AB3100_RTC_CLOCK_RATE * 2;
+ buf[0] = (hw_counter >> 16) & 0xFF;
+ buf[1] = (hw_counter >> 24) & 0xFF;
+ buf[2] = (hw_counter >> 32) & 0xFF;
+ buf[3] = (hw_counter >> 40) & 0xFF;

/* Set the alarm */
for (i = 0; i < 4; i++) {
@@ -193,7 +192,7 @@ static int ab3100_rtc_irq_enable(struct device *dev, unsigned int enabled)

static const struct rtc_class_ops ab3100_rtc_ops = {
.read_time = ab3100_rtc_read_time,
- .set_mmss = ab3100_rtc_set_mmss,
+ .set_mmss64 = ab3100_rtc_set_mmss,
.read_alarm = ab3100_rtc_read_alarm,
.set_alarm = ab3100_rtc_set_alarm,
.alarm_irq_enable = ab3100_rtc_irq_enable,
--
1.9.1


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