[PATCH V2 31/63] clocksource/drivers/tango_xtal: Convert init function to return error

From: Daniel Lezcano
Date: Thu Jun 16 2016 - 17:38:14 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/sun4i_timer.c | 45 ++++++++++++++++++++++++++++-----------
1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index 6f3719d..4453730 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -146,7 +146,7 @@ static u64 notrace sun4i_timer_sched_read(void)
return ~readl(timer_base + TIMER_CNTVAL_REG(1));
}

-static void __init sun4i_timer_init(struct device_node *node)
+static int __init sun4i_timer_init(struct device_node *node)
{
unsigned long rate = 0;
struct clk *clk;
@@ -154,17 +154,28 @@ static void __init sun4i_timer_init(struct device_node *node)
u32 val;

timer_base = of_iomap(node, 0);
- if (!timer_base)
- panic("Can't map registers");
+ if (!timer_base) {
+ pr_crit("Can't map registers");
+ return -ENXIO;
+ }

irq = irq_of_parse_and_map(node, 0);
- if (irq <= 0)
- panic("Can't parse IRQ");
+ if (irq <= 0) {
+ pr_crit("Can't parse IRQ");
+ return -EINVAL;
+ }

clk = of_clk_get(node, 0);
- if (IS_ERR(clk))
- panic("Can't get timer clock");
- clk_prepare_enable(clk);
+ if (IS_ERR(clk)) {
+ pr_crit("Can't get timer clock");
+ return PTR_ERR(clk);
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (ret) {
+ pr_err("Failed to prepare clock");
+ return ret;
+ }

rate = clk_get_rate(clk);

@@ -182,8 +193,12 @@ static void __init sun4i_timer_init(struct device_node *node)
of_machine_is_compatible("allwinner,sun5i-a10s"))
sched_clock_register(sun4i_timer_sched_read, 32, rate);

- clocksource_mmio_init(timer_base + TIMER_CNTVAL_REG(1), node->name,
- rate, 350, 32, clocksource_mmio_readl_down);
+ ret = clocksource_mmio_init(timer_base + TIMER_CNTVAL_REG(1), node->name,
+ rate, 350, 32, clocksource_mmio_readl_down);
+ if (ret) {
+ pr_err("Failed to register clocksource");
+ return ret;
+ }

ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);

@@ -200,12 +215,16 @@ static void __init sun4i_timer_init(struct device_node *node)
TIMER_SYNC_TICKS, 0xffffffff);

ret = setup_irq(irq, &sun4i_timer_irq);
- if (ret)
- pr_warn("failed to setup irq %d\n", irq);
+ if (ret) {
+ pr_err("failed to setup irq %d\n", irq);
+ return ret;
+ }

/* Enable timer0 interrupt */
val = readl(timer_base + TIMER_IRQ_EN_REG);
writel(val | TIMER_IRQ_EN(0), timer_base + TIMER_IRQ_EN_REG);
+
+ return ret;
}
-CLOCKSOURCE_OF_DECLARE(sun4i, "allwinner,sun4i-a10-timer",
+CLOCKSOURCE_OF_DECLARE_RET(sun4i, "allwinner,sun4i-a10-timer",
sun4i_timer_init);
--
1.9.1