rtc: restoring of periodic irq freqeuncy to original state

[dev@xxxxxxxxxxxxxxxxxx]

Hi Kernel Folks,

Dont' know whether this is a bug or feature. sorry :(.

when the periodic irq's are enabled from the application through the 
ioctl, and when the application suddenly stops, the irq frequency was 
not reverted back to the original one.

say for ex..
           if my original freq was 1024, and i set it using IRQP_SET 
with 512.
           so when i stop my program the original freq was not set back 
and the program set frequency is appearing in the /proc/driver/rtc.

Attached is the test program.


Thanks,
Devendra C.

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/rtc.h>

main()
{
    struct rtc_time rtc_time;
    int fd;
    char data[BUFSIZ];
    int irqfre;
    int ret;

    fd = open("/dev/rtc", O_RDWR);
    if (fd < 0) {
        printf("can't open /dev/rtc\n");
        return;
    }

    ret = ioctl(fd, RTC_IRQP_READ, &irqfre);
    if (ret == 0) {
        /*
        printf("Rate: %d\n", irqfre);
        */
        irqfre =  1024;
        ret = ioctl(fd, RTC_IRQP_SET, irqfre);
    }
    if (ret < 0) {
        printf("Can't read periodic IRQ's\n");
    }

    ret = ioctl(fd, RTC_PIE_ON, NULL);
    if (ret < 0) {
        printf("can't set the periodic irq\n");
        close(fd);
        return;
    }

    
    while(read(fd, &data, sizeof(data)) > 0) {
        printf("Intr\n");
    }
    
}