clocksource/drivers/tegra20: 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/drivers/clocksource/tegra20_timer.c b/drivers/clocksource/tegra20_timer.c
index 7b94ad2ab27861192f08601cd5cb787d94111806..543c37e3a62c2656cb8d27ce49f50ff599cc8553 100644 (file)
--- a/drivers/clocksource/tegra20_timer.c
+++ b/drivers/clocksource/tegra20_timer.c
@@ -165,7 +165,7 @@ static struct irqaction tegra_timer_irq = {
        .dev_id         = &tegra_clockevent,
 };
 
-static void __init tegra20_init_timer(struct device_node *np)
+static int __init tegra20_init_timer(struct device_node *np)
 {
        struct clk *clk;
        unsigned long rate;
@@ -174,13 +174,13 @@ static void __init tegra20_init_timer(struct device_node *np)
        timer_reg_base = of_iomap(np, 0);
        if (!timer_reg_base) {
                pr_err("Can't map timer registers\n");
-               BUG();
+               return -ENXIO;
        }
 
        tegra_timer_irq.irq = irq_of_parse_and_map(np, 2);
        if (tegra_timer_irq.irq <= 0) {
                pr_err("Failed to map timer IRQ\n");
-               BUG();
+               return -EINVAL;
        }
 
        clk = of_clk_get(np, 0);
@@ -211,10 +211,12 @@ static void __init tegra20_init_timer(struct device_node *np)
 
        sched_clock_register(tegra_read_sched_clock, 32, 1000000);
 
-       if (clocksource_mmio_init(timer_reg_base + TIMERUS_CNTR_1US,
-               "timer_us", 1000000, 300, 32, clocksource_mmio_readl_up)) {
+       ret = clocksource_mmio_init(timer_reg_base + TIMERUS_CNTR_1US,
+                                   "timer_us", 1000000, 300, 32,
+                                   clocksource_mmio_readl_up);
+       if (ret) {
                pr_err("Failed to register clocksource\n");
-               BUG();
+               return ret;
        }
 
        tegra_delay_timer.read_current_timer =
@@ -225,24 +227,26 @@ static void __init tegra20_init_timer(struct device_node *np)
        ret = setup_irq(tegra_timer_irq.irq, &tegra_timer_irq);
        if (ret) {
                pr_err("Failed to register timer IRQ: %d\n", ret);
-               BUG();
+               return ret;
        }
 
        tegra_clockevent.cpumask = cpu_all_mask;
        tegra_clockevent.irq = tegra_timer_irq.irq;
        clockevents_config_and_register(&tegra_clockevent, 1000000,
                                        0x1, 0x1fffffff);
+
+       return 0;
 }
-CLOCKSOURCE_OF_DECLARE(tegra20_timer, "nvidia,tegra20-timer", tegra20_init_timer);
+CLOCKSOURCE_OF_DECLARE_RET(tegra20_timer, "nvidia,tegra20-timer", tegra20_init_timer);
 
-static void __init tegra20_init_rtc(struct device_node *np)
+static int __init tegra20_init_rtc(struct device_node *np)
 {
        struct clk *clk;
 
        rtc_base = of_iomap(np, 0);
        if (!rtc_base) {
                pr_err("Can't map RTC registers");
-               BUG();
+               return -ENXIO;
        }
 
        /*
@@ -255,6 +259,6 @@ static void __init tegra20_init_rtc(struct device_node *np)
        else
                clk_prepare_enable(clk);
 
-       register_persistent_clock(NULL, tegra_read_persistent_clock64);
+       return register_persistent_clock(NULL, tegra_read_persistent_clock64);
 }
-CLOCKSOURCE_OF_DECLARE(tegra20_rtc, "nvidia,tegra20-rtc", tegra20_init_rtc);
+CLOCKSOURCE_OF_DECLARE_RET(tegra20_rtc, "nvidia,tegra20-rtc", tegra20_init_rtc);