static int kpowerswd()

in power.c [115:161]

• 25 lines of code
• 8 McCabe index (conditional complexity)

static int kpowerswd(void *param)
{
	__set_current_state(TASK_RUNNING);

	do {
		int button_not_pressed;
		unsigned long soft_power_reg = (unsigned long) param;

		schedule_timeout_interruptible(pwrsw_enabled ? HZ : HZ/POWERSWITCH_POLL_PER_SEC);

		if (unlikely(!pwrsw_enabled))
			continue;

		if (soft_power_reg) {
			/*
			 * Non-Gecko-style machines:
			 * Check the power switch status which is read from the
			 * real I/O location at soft_power_reg.
			 * Bit 31 ("the lowest bit) is the status of the power switch.
			 * This bit is "1" if the button is NOT pressed.
			 */
			button_not_pressed = (gsc_readl(soft_power_reg) & 0x1);
		} else {
			/*
			 * On gecko style machines (e.g. 712/xx and 715/xx) 
			 * the power switch status is stored in Bit 0 ("the highest bit")
			 * of CPU diagnose register 25.
			 * Warning: Some machines never reset the DIAG flag, even if
			 * the button has been released again.
			 */
			button_not_pressed = (__getDIAG(25) & 0x80000000);
		}

		if (likely(button_not_pressed)) {
			if (unlikely(shutdown_timer && /* avoid writing if not necessary */
				shutdown_timer < (POWERSWITCH_DOWN_SEC*POWERSWITCH_POLL_PER_SEC))) {
				shutdown_timer = 0;
				printk(KERN_INFO KTHREAD_NAME ": Shutdown request aborted.\n");
			}
		} else
			process_shutdown();


	} while (!kthread_should_stop());

	return 0;
}