parisc/power: Add power soft-off when running on qemu

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v6.0+

drivers/parisc/power.c

@@ -197,6 +197,14 @@ static struct notifier_block parisc_panic_block = {
 	.priority	= INT_MAX,
 };
 
+/* qemu soft power-off function */
+static int qemu_power_off(struct sys_off_data *data)
+{
+	/* this turns the system off via SeaBIOS */
+	*(int *)data->cb_data = 0;
+	pdc_soft_power_button(1);
+	return NOTIFY_DONE;
+}
 
 static int __init power_init(void)
 {
@@ -226,7 +234,13 @@ static int __init power_init(void)
 				soft_power_reg);
 	}
 
-	power_task = kthread_run(kpowerswd, (void*)soft_power_reg, KTHREAD_NAME);
+	power_task = NULL;
+	if (running_on_qemu && soft_power_reg)
+		register_sys_off_handler(SYS_OFF_MODE_POWER_OFF, SYS_OFF_PRIO_DEFAULT,
+					qemu_power_off, (void *)soft_power_reg);
+	else
+		power_task = kthread_run(kpowerswd, (void*)soft_power_reg,
+					KTHREAD_NAME);
 	if (IS_ERR(power_task)) {
 		printk(KERN_ERR DRIVER_NAME ": thread creation failed.  Driver not loaded.\n");
 		pdc_soft_power_button(0);