[PATCH 37/93] clocksource/drivers/nomadik-mtu: Convert init function to return error

From: Daniel Lezcano
Date: Thu Jul 07 2016 - 04:03:43 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/nomadik-mtu.c | 45 +++++++++++++++++++++++++--------------
1 file changed, 29 insertions(+), 16 deletions(-)

diff --git a/drivers/clocksource/nomadik-mtu.c b/drivers/clocksource/nomadik-mtu.c
index bc8dd44..d2be5b3 100644
--- a/drivers/clocksource/nomadik-mtu.c
+++ b/drivers/clocksource/nomadik-mtu.c
@@ -193,10 +193,11 @@ static struct irqaction nmdk_timer_irq = {
.dev_id = &nmdk_clkevt,
};

-static void __init nmdk_timer_init(void __iomem *base, int irq,
+static int __init nmdk_timer_init(void __iomem *base, int irq,
struct clk *pclk, struct clk *clk)
{
unsigned long rate;
+ int ret;

mtu_base = base;

@@ -226,10 +227,12 @@ static void __init nmdk_timer_init(void __iomem *base, int irq,
/* Timer 0 is the free running clocksource */
nmdk_clksrc_reset();

- if (clocksource_mmio_init(mtu_base + MTU_VAL(0), "mtu_0",
- rate, 200, 32, clocksource_mmio_readl_down))
- pr_err("timer: failed to initialize clock source %s\n",
- "mtu_0");
+ ret = clocksource_mmio_init(mtu_base + MTU_VAL(0), "mtu_0",
+ rate, 200, 32, clocksource_mmio_readl_down);
+ if (ret) {
+ pr_err("timer: failed to initialize clock source %s\n", "mtu_0");
+ return ret;
+ }

#ifdef CONFIG_CLKSRC_NOMADIK_MTU_SCHED_CLOCK
sched_clock_register(nomadik_read_sched_clock, 32, rate);
@@ -244,9 +247,11 @@ static void __init nmdk_timer_init(void __iomem *base, int irq,
mtu_delay_timer.read_current_timer = &nmdk_timer_read_current_timer;
mtu_delay_timer.freq = rate;
register_current_timer_delay(&mtu_delay_timer);
+
+ return 0;
}

-static void __init nmdk_timer_of_init(struct device_node *node)
+static int __init nmdk_timer_of_init(struct device_node *node)
{
struct clk *pclk;
struct clk *clk;
@@ -254,22 +259,30 @@ static void __init nmdk_timer_of_init(struct device_node *node)
int irq;

base = of_iomap(node, 0);
- if (!base)
- panic("Can't remap registers");
+ if (!base) {
+ pr_err("Can't remap registers");
+ return -ENXIO;
+ }

pclk = of_clk_get_by_name(node, "apb_pclk");
- if (IS_ERR(pclk))
- panic("could not get apb_pclk");
+ if (IS_ERR(pclk)) {
+ pr_err("could not get apb_pclk");
+ return PTR_ERR(pclk);
+ }

clk = of_clk_get_by_name(node, "timclk");
- if (IS_ERR(clk))
- panic("could not get timclk");
+ if (IS_ERR(clk)) {
+ pr_err("could not get timclk");
+ return PTR_ERR(clk);
+ }

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

- nmdk_timer_init(base, irq, pclk, clk);
+ return nmdk_timer_init(base, irq, pclk, clk);
}
-CLOCKSOURCE_OF_DECLARE(nomadik_mtu, "st,nomadik-mtu",
+CLOCKSOURCE_OF_DECLARE_RET(nomadik_mtu, "st,nomadik-mtu",
nmdk_timer_of_init);
--
1.9.1