x86/lguest/timer: Migrate to new set-state interface

Migrate lguest driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

We weren't doing anything while switching modes other than in shutdown
mode and so those are not implemented.

Signed-off-by: Viresh Kumar <[e-mail]>
Acked-and-tested-by: Rusty Russell <[e-mail]>
Cc: [e-mail]
Cc: Alexander Kuleshov <[e-mail]>
Cc: Brian Gerst <[e-mail]>
Cc: Denys Vlasenko <[e-mail]>
Cc: Jan Beulich <[e-mail]>
Cc: Andy Lutomirski <[e-mail]>
Cc: [e-mail] (open list:LGUEST)
Link: http://lkml.kernel.org/r/b96f[e-mail]
Signed-off-by: Thomas Gleixner <[e-mail]>

arch/x86/lguest/boot.c

···
 	return 0;
 }
 
-static void lguest_clockevent_set_mode(enum clock_event_mode mode,
-                                      struct clock_event_device *evt)
+static int lguest_clockevent_shutdown(struct clock_event_device *evt)
 {
-	switch (mode) {
-	case CLOCK_EVT_MODE_UNUSED:
-	case CLOCK_EVT_MODE_SHUTDOWN:
-		/* A 0 argument shuts the clock down. */
-		hcall(LHCALL_SET_CLOCKEVENT, 0, 0, 0, 0);
-		break;
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* This is what we expect. */
-		break;
-	case CLOCK_EVT_MODE_PERIODIC:
-		BUG();
-	case CLOCK_EVT_MODE_RESUME:
-		break;
-	}
+	/* A 0 argument shuts the clock down. */
+	hcall(LHCALL_SET_CLOCKEVENT, 0, 0, 0, 0);
+	return 0;
 }
 
 /* This describes our primitive timer chip. */
···
 	.name                   = "lguest",
 	.features               = CLOCK_EVT_FEAT_ONESHOT,
 	.set_next_event         = lguest_clockevent_set_next_event,
-	.set_mode               = lguest_clockevent_set_mode,
+	.set_state_shutdown	= lguest_clockevent_shutdown,
 	.rating                 = INT_MAX,
 	.mult                   = 1,
 	.shift                  = 0,