[PATCH 70/93] clocksource/drivers/arc: Convert init function to return error

From: Daniel Lezcano
Date: Thu Jul 07 2016 - 04:19:09 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/arc/kernel/time.c | 69 ++++++++++++++++++++++++++++++--------------------
1 file changed, 42 insertions(+), 27 deletions(-)

diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index 4549ab2..09de669 100644
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -116,21 +116,21 @@ static struct clocksource arc_counter_gfrc = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};

-static void __init arc_cs_setup_gfrc(struct device_node *node)
+static int __init arc_cs_setup_gfrc(struct device_node *node)
{
int exists = cpuinfo_arc700[0].extn.gfrc;
int ret;

if (WARN(!exists, "Global-64-bit-Ctr clocksource not detected"))
- return;
+ return -ENXIO;

ret = arc_get_timer_clk(node);
if (ret)
- return;
+ return ret;

- clocksource_register_hz(&arc_counter_gfrc, arc_timer_freq);
+ return clocksource_register_hz(&arc_counter_gfrc, arc_timer_freq);
}
-CLOCKSOURCE_OF_DECLARE(arc_gfrc, "snps,archs-timer-gfrc", arc_cs_setup_gfrc);
+CLOCKSOURCE_OF_DECLARE_RET(arc_gfrc, "snps,archs-timer-gfrc", arc_cs_setup_gfrc);

#endif

@@ -172,27 +172,27 @@ static struct clocksource arc_counter_rtc = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};

-static void __init arc_cs_setup_rtc(struct device_node *node)
+static int __init arc_cs_setup_rtc(struct device_node *node)
{
int exists = cpuinfo_arc700[smp_processor_id()].extn.rtc;
int ret;

if (WARN(!exists, "Local-64-bit-Ctr clocksource not detected"))
- return;
+ return -ENXIO;

/* Local to CPU hence not usable in SMP */
if (WARN(IS_ENABLED(CONFIG_SMP), "Local-64-bit-Ctr not usable in SMP"))
- return;
+ return -EINVAL;

ret = arc_get_timer_clk(node);
if (ret)
- return;
+ return ret;

write_aux_reg(AUX_RTC_CTRL, 1);

- clocksource_register_hz(&arc_counter_rtc, arc_timer_freq);
+ return clocksource_register_hz(&arc_counter_rtc, arc_timer_freq);
}
-CLOCKSOURCE_OF_DECLARE(arc_rtc, "snps,archs-timer-rtc", arc_cs_setup_rtc);
+CLOCKSOURCE_OF_DECLARE_RET(arc_rtc, "snps,archs-timer-rtc", arc_cs_setup_rtc);

#endif

@@ -213,23 +213,23 @@ static struct clocksource arc_counter_timer1 = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};

-static void __init arc_cs_setup_timer1(struct device_node *node)
+static int __init arc_cs_setup_timer1(struct device_node *node)
{
int ret;

/* Local to CPU hence not usable in SMP */
if (IS_ENABLED(CONFIG_SMP))
- return;
+ return -EINVAL;

ret = arc_get_timer_clk(node);
if (ret)
- return;
+ return ret;

write_aux_reg(ARC_REG_TIMER1_LIMIT, ARC_TIMER_MAX);
write_aux_reg(ARC_REG_TIMER1_CNT, 0);
write_aux_reg(ARC_REG_TIMER1_CTRL, TIMER_CTRL_NH);

- clocksource_register_hz(&arc_counter_timer1, arc_timer_freq);
+ return clocksource_register_hz(&arc_counter_timer1, arc_timer_freq);
}

/********** Clock Event Device *********/
@@ -324,20 +324,28 @@ static struct notifier_block arc_timer_cpu_nb = {
/*
* clockevent setup for boot CPU
*/
-static void __init arc_clockevent_setup(struct device_node *node)
+static int __init arc_clockevent_setup(struct device_node *node)
{
struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device);
int ret;

- register_cpu_notifier(&arc_timer_cpu_nb);
+ ret = register_cpu_notifier(&arc_timer_cpu_nb);
+ if (ret) {
+ pr_err("Failed to register cpu notifier");
+ return ret;
+ }

arc_timer_irq = irq_of_parse_and_map(node, 0);
- if (arc_timer_irq <= 0)
- panic("clockevent: missing irq");
+ if (arc_timer_irq <= 0) {
+ pr_err("clockevent: missing irq");
+ return -EINVAL;
+ }

ret = arc_get_timer_clk(node);
- if (ret)
- panic("clockevent: missing clk");
+ if (ret) {
+ pr_err("clockevent: missing clk");
+ return ret;
+ }

evt->irq = arc_timer_irq;
evt->cpumask = cpumask_of(smp_processor_id());
@@ -347,24 +355,31 @@ static void __init arc_clockevent_setup(struct device_node *node)
/* Needs apriori irq_set_percpu_devid() done in intc map function */
ret = request_percpu_irq(arc_timer_irq, timer_irq_handler,
"Timer0 (per-cpu-tick)", evt);
- if (ret)
- panic("clockevent: unable to request irq\n");
+ if (ret) {
+ pr_err("clockevent: unable to request irq\n");
+ return ret;
+ }

enable_percpu_irq(arc_timer_irq, 0);
+
+ return 0;
}

-static void __init arc_of_timer_init(struct device_node *np)
+static int __init arc_of_timer_init(struct device_node *np)
{
static int init_count = 0;
+ int ret;

if (!init_count) {
init_count = 1;
- arc_clockevent_setup(np);
+ ret = arc_clockevent_setup(np);
} else {
- arc_cs_setup_timer1(np);
+ ret = arc_cs_setup_timer1(np);
}
+
+ return ret;
}
-CLOCKSOURCE_OF_DECLARE(arc_clkevt, "snps,arc-timer", arc_of_timer_init);
+CLOCKSOURCE_OF_DECLARE_RET(arc_clkevt, "snps,arc-timer", arc_of_timer_init);

/*
* Called from start_kernel() - boot CPU only
--
1.9.1