There is no power off command on i.MX53 and how to do it?
In linux, there is a standard interface for power off. It is a system call.
In kernel/sys.c,
SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
void __user *, arg)
{
...
case LINUX_REBOOT_CMD_POWER_OFF:
kernel_power_off();
do_exit(0);
break;
}
kernel_power_off will invoke pm_power_off which is a function pointer. It is defined to be da9053_power_off on i.MX53.
It will cut off PMIC power directly.
So, in user space, we just need to issue a system call with correct magic number and command.
The sample code is quite easy and list below:
#include <unistd.h>
#include <sys/reboot.h>
int main(void)
{
return __reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2,
LINUX_REBOOT_CMD_POWER_OFF, NULL);
}
The code can be found at:
reboot.c
