[PATCH V2 42/63] clocksource/drivers/prima2: Convert init function to return error

[Daniel Lezcano]

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.lezc...@linaro.org>
---
 drivers/clocksource/timer-prima2.c | 43 ++++++++++++++++++++++++++++----------
 1 file changed, 32 insertions(+), 11 deletions(-)

diff --git a/drivers/clocksource/timer-prima2.c 
b/drivers/clocksource/timer-prima2.c
index 2854c66..7b1084d 100644
--- a/drivers/clocksource/timer-prima2.c
+++ b/drivers/clocksource/timer-prima2.c
@@ -189,24 +189,36 @@ static void __init sirfsoc_clockevent_init(void)
 }
 
 /* initialize the kernel jiffy timer source */
-static void __init sirfsoc_prima2_timer_init(struct device_node *np)
+static int __init sirfsoc_prima2_timer_init(struct device_node *np)
 {
        unsigned long rate;
        struct clk *clk;
+       int ret;
 
        clk = of_clk_get(np, 0);
-       BUG_ON(IS_ERR(clk));
+       if (IS_ERR(clk)) {
+               pr_err("Failed to get clock");
+               return PTR_ERR(clk);
+       }
 
-       BUG_ON(clk_prepare_enable(clk));
+       ret = clk_prepare_enable(clk);
+       if (ret) {
+               pr_err("Failed to enable clock");
+               return ret;
+       }
 
        rate = clk_get_rate(clk);
 
-       BUG_ON(rate < PRIMA2_CLOCK_FREQ);
-       BUG_ON(rate % PRIMA2_CLOCK_FREQ);
+       if (rate < PRIMA2_CLOCK_FREQ || rate % PRIMA2_CLOCK_FREQ) {
+               pr_err("Invalid clock rate");
+               return -EINVAL;
+       }
 
        sirfsoc_timer_base = of_iomap(np, 0);
-       if (!sirfsoc_timer_base)
-               panic("unable to map timer cpu registers\n");
+       if (!sirfsoc_timer_base) {
+               pr_err("unable to map timer cpu registers\n");
+               return -ENXIO;
+       }
 
        sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);
 
@@ -216,14 +228,23 @@ static void __init sirfsoc_prima2_timer_init(struct 
device_node *np)
        writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);
        writel_relaxed(BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_STATUS);
 
-       BUG_ON(clocksource_register_hz(&sirfsoc_clocksource,
-                                      PRIMA2_CLOCK_FREQ));
+       ret = clocksource_register_hz(&sirfsoc_clocksource, PRIMA2_CLOCK_FREQ);
+       if (ret) {
+               pr_err("Failed to register clocksource");
+               return ret;
+       }
 
        sched_clock_register(sirfsoc_read_sched_clock, 64, PRIMA2_CLOCK_FREQ);
 
-       BUG_ON(setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq));
+       ret = setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq);
+       if (ret) {
+               pr_err("Failed to setup irq");
+               return ret;
+       }
 
        sirfsoc_clockevent_init();
+
+       return 0;
 }
-CLOCKSOURCE_OF_DECLARE(sirfsoc_prima2_timer,
+CLOCKSOURCE_OF_DECLARE_RET(sirfsoc_prima2_timer,
        "sirf,prima2-tick", sirfsoc_prima2_timer_init);
-- 
1.9.1