clocksource/drivers/microblaze: 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: Daniel Lezcano <daniel.lezcano@linaro.org>

diff --git a/arch/microblaze/kernel/timer.c b/arch/microblaze/kernel/timer.c
index 67e2ef48d2d0156fc9a4ab3c62e46867a43a04a5..7f35e7b50f1b70a12697dc907ab6e14407ff2350 100644 (file)
--- a/arch/microblaze/kernel/timer.c
+++ b/arch/microblaze/kernel/timer.c
@@ -170,7 +170,7 @@ static struct irqaction timer_irqaction = {
        .dev_id = &clockevent_xilinx_timer,
 };
 
-static __init void xilinx_clockevent_init(void)
+static __init int xilinx_clockevent_init(void)
 {
        clockevent_xilinx_timer.mult =
                div_sc(timer_clock_freq, NSEC_PER_SEC,
@@ -181,6 +181,8 @@ static __init void xilinx_clockevent_init(void)
                clockevent_delta2ns(1, &clockevent_xilinx_timer);
        clockevent_xilinx_timer.cpumask = cpumask_of(0);
        clockevents_register_device(&clockevent_xilinx_timer);
+
+       return 0;
 }
 
 static u64 xilinx_clock_read(void)
@@ -229,8 +231,14 @@ static struct clocksource clocksource_microblaze = {
 
 static int __init xilinx_clocksource_init(void)
 {
-       if (clocksource_register_hz(&clocksource_microblaze, timer_clock_freq))
-               panic("failed to register clocksource");
+       int ret;
+
+       ret = clocksource_register_hz(&clocksource_microblaze,
+                                     timer_clock_freq);
+       if (ret) {
+               pr_err("failed to register clocksource");
+               return ret;
+       }
 
        /* stop timer1 */
        write_fn(read_fn(timer_baseaddr + TCSR1) & ~TCSR_ENT,
@@ -239,16 +247,16 @@ static int __init xilinx_clocksource_init(void)
        write_fn(TCSR_TINT|TCSR_ENT|TCSR_ARHT, timer_baseaddr + TCSR1);
 
        /* register timecounter - for ftrace support */
-       init_xilinx_timecounter();
-       return 0;
+       return init_xilinx_timecounter();
 }
 
-static void __init xilinx_timer_init(struct device_node *timer)
+static int __init xilinx_timer_init(struct device_node *timer)
 {
        struct clk *clk;
        static int initialized;
        u32 irq;
        u32 timer_num = 1;
+       int ret;
 
        if (initialized)
                return;
@@ -258,7 +266,7 @@ static void __init xilinx_timer_init(struct device_node *timer)
        timer_baseaddr = of_iomap(timer, 0);
        if (!timer_baseaddr) {
                pr_err("ERROR: invalid timer base address\n");
-               BUG();
+               return -ENXIO;
        }
 
        write_fn = timer_write32;
@@ -271,11 +279,15 @@ static void __init xilinx_timer_init(struct device_node *timer)
        }
 
        irq = irq_of_parse_and_map(timer, 0);
+       if (irq <= 0) {
+               pr_err("Failed to parse and map irq");
+               return -EINVAL;
+       }
 
        of_property_read_u32(timer, "xlnx,one-timer-only", &timer_num);
        if (timer_num) {
-               pr_emerg("Please enable two timers in HW\n");
-               BUG();
+               pr_err("Please enable two timers in HW\n");
+               return -EINVAL;
        }
 
        pr_info("%s: irq=%d\n", timer->full_name, irq);
@@ -297,15 +309,28 @@ static void __init xilinx_timer_init(struct device_node *timer)
 
        freq_div_hz = timer_clock_freq / HZ;
 
-       setup_irq(irq, &timer_irqaction);
+       ret = setup_irq(irq, &timer_irqaction);
+       if (ret) {
+               pr_err("Failed to setup IRQ");
+               return ret;
+       }
+
 #ifdef CONFIG_HEART_BEAT
        microblaze_setup_heartbeat();
 #endif
-       xilinx_clocksource_init();
-       xilinx_clockevent_init();
+
+       ret = xilinx_clocksource_init();
+       if (ret)
+               return ret;
+
+       ret = xilinx_clockevent_init();
+       if (ret)
+               return ret;
 
        sched_clock_register(xilinx_clock_read, 32, timer_clock_freq);
+
+       return 0;
 }
 
-CLOCKSOURCE_OF_DECLARE(xilinx_timer, "xlnx,xps-timer-1.00.a",
+CLOCKSOURCE_OF_DECLARE_RET(xilinx_timer, "xlnx,xps-timer-1.00.a",
                       xilinx_timer_init);