Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rtc: fix deadlock
+4
-8
include/asm-generic/rtc.h
+4
-8
include/asm-generic/rtc.h
···
15
#include <linux/mc146818rtc.h>
16
#include <linux/rtc.h>
17
#include <linux/bcd.h>
18
19
#define RTC_PIE 0x40 /* periodic interrupt enable */
20
#define RTC_AIE 0x20 /* alarm interrupt enable */
···
44
45
static inline unsigned int get_rtc_time(struct rtc_time *time)
46
{
47
-
unsigned long uip_watchdog = jiffies;
48
unsigned char ctrl;
49
unsigned long flags;
50
···
53
54
/*
55
* read RTC once any update in progress is done. The update
56
-
* can take just over 2ms. We wait 10 to 20ms. There is no need to
57
* to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.
58
* If you need to know *exactly* when a second has started, enable
59
* periodic update complete interrupts, (via ioctl) and then
60
* immediately read /dev/rtc which will block until you get the IRQ.
61
* Once the read clears, read the RTC time (again via ioctl). Easy.
62
*/
63
-
64
-
if (rtc_is_updating() != 0)
65
-
while (jiffies - uip_watchdog < 2*HZ/100) {
66
-
barrier();
67
-
cpu_relax();
68
-
}
69
70
/*
71
* Only the values that we read from the RTC are set. We leave
···
15
#include <linux/mc146818rtc.h>
16
#include <linux/rtc.h>
17
#include <linux/bcd.h>
18
+
#include <linux/delay.h>
19
20
#define RTC_PIE 0x40 /* periodic interrupt enable */
21
#define RTC_AIE 0x20 /* alarm interrupt enable */
···
43
44
static inline unsigned int get_rtc_time(struct rtc_time *time)
45
{
46
unsigned char ctrl;
47
unsigned long flags;
48
···
53
54
/*
55
* read RTC once any update in progress is done. The update
56
+
* can take just over 2ms. We wait 20ms. There is no need to
57
* to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.
58
* If you need to know *exactly* when a second has started, enable
59
* periodic update complete interrupts, (via ioctl) and then
60
* immediately read /dev/rtc which will block until you get the IRQ.
61
* Once the read clears, read the RTC time (again via ioctl). Easy.
62
*/
63
+
if (rtc_is_updating())
64
+
mdelay(20);
65
66
/*
67
* Only the values that we read from the RTC are set. We leave