[PATCH V3] clocksource/drivers/tegra20: Convert init function to return error

From: Daniel Lezcano
Date: Fri Jun 17 2016 - 05:07:20 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>
---
drivers/clocksource/tegra20_timer.c | 28 ++++++++++++++++------------
1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/clocksource/tegra20_timer.c b/drivers/clocksource/tegra20_timer.c
index 7b94ad2..543c37e 100644
--- 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);
--
1.9.1