[PATCH V2 56/63] clocksource/drivers/microblaze: Convert init function to return error

From: Daniel Lezcano
Date: Thu Jun 16 2016 - 17:32:26 EST


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@xxxxxxxxxx>
---
arch/microblaze/kernel/timer.c | 51 +++++++++++++++++++++++++++++++-----------
1 file changed, 38 insertions(+), 13 deletions(-)

diff --git a/arch/microblaze/kernel/timer.c b/arch/microblaze/kernel/timer.c
index 67e2ef4..7f35e7b 100644
--- 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);
--
1.9.1