clocksource/drivers/ti-32k: Convert init function to return error

The init functions do not return any error. They behave as the following:

  - panic, thus leading to a kernel crash while another timer may work and
       make the system boot up correctly

  or

  - print an error and let the caller unaware if the state of the system

Change that by converting the init functions to return an error conforming
to the CLOCKSOURCE_OF_RET prototype.

Proper error handling (rollback, errno value) will be changed later case
by case, thus this change just return back an error or success in the init
function.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

drivers/clocksource/timer-ti-32k.c

@@ -88,14 +88,14 @@ static u64 notrace omap_32k_read_sched_clock(void)
 	return ti_32k_read_cycles(&ti_32k_timer.cs);
 }
 
-static void __init ti_32k_timer_init(struct device_node *np)
+static int __init ti_32k_timer_init(struct device_node *np)
 {
 	int ret;
 
 	ti_32k_timer.base = of_iomap(np, 0);
 	if (!ti_32k_timer.base) {
 		pr_err("Can't ioremap 32k timer base\n");
-		return;
+		return -ENXIO;
 	}
 
 	ti_32k_timer.counter = ti_32k_timer.base;
@@ -116,11 +116,13 @@ static void __init ti_32k_timer_init(struct device_node *np)
 	ret = clocksource_register_hz(&ti_32k_timer.cs, 32768);
 	if (ret) {
 		pr_err("32k_counter: can't register clocksource\n");
-		return;
+		return ret;
 	}
 
 	sched_clock_register(omap_32k_read_sched_clock, 32, 32768);
 	pr_info("OMAP clocksource: 32k_counter at 32768 Hz\n");
+
+	return 0;
 }
-CLOCKSOURCE_OF_DECLARE(ti_32k_timer, "ti,omap-counter32k",
+CLOCKSOURCE_OF_DECLARE_RET(ti_32k_timer, "ti,omap-counter32k",
 		ti_32k_timer_init);