[PATCH v4] clocksource: clps711x: Fix resource leaks in error paths

[Zhen Ni <zhen.ni@easystack.cn>]

The current implementation of clps711x_timer_init() has multiple error
paths that directly return without releasing the base I/O memory mapped
via of_iomap(). Fix of_iomap leaks in error paths.

Fixes: 04410efbb6bc ("clocksource/drivers/clps711x: Convert init function to return error")
Fixes: 2a6a8e2d9004 ("clocksource/drivers/clps711x: Remove board support")
Cc: stable@vger.kernel.org
Signed-off-by: Zhen Ni <zhen.ni@easystack.cn>
---
changes in v4:
- Change the default value of ret from 0 to -INVAL
- Do not release the iomap in success paths
changes in v3:
- Change "err" to "error" in the commit message.
changes in v2:
- Add tags of 'Fixes' and 'Cc'
- Reduce detailed enumeration of err paths
- Omit a pointer check before iounmap()
- Change goto target from out to unmap_io
---
 drivers/clocksource/clps711x-timer.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/clocksource/clps711x-timer.c b/drivers/clocksource/clps711x-timer.c
index e95fdc49c226..84dbcd049c25 100644
--- a/drivers/clocksource/clps711x-timer.c
+++ b/drivers/clocksource/clps711x-timer.c
@@ -78,24 +78,33 @@ static int __init clps711x_timer_init(struct device_node *np)
 	unsigned int irq = irq_of_parse_and_map(np, 0);
 	struct clk *clock = of_clk_get(np, 0);
 	void __iomem *base = of_iomap(np, 0);
+	int ret = -EINVAL;
 
 	if (!base)
 		return -ENOMEM;
 	if (!irq)
-		return -EINVAL;
-	if (IS_ERR(clock))
-		return PTR_ERR(clock);
+		goto unmap_io;
+	if (IS_ERR(clock)) {
+		ret = PTR_ERR(clock);
+		goto unmap_io;
+	}
 
 	switch (of_alias_get_id(np, "timer")) {
 	case CLPS711X_CLKSRC_CLOCKSOURCE:
 		clps711x_clksrc_init(clock, base);
+		ret = 0;
 		break;
 	case CLPS711X_CLKSRC_CLOCKEVENT:
-		return _clps711x_clkevt_init(clock, base, irq);
+		ret =  _clps711x_clkevt_init(clock, base, irq);
+		break;
 	default:
-		return -EINVAL;
+		break;
 	}
+	if (!ret)
+		return ret;
 
-	return 0;
+unmap_io:
+	iounmap(base);
+	return ret;
 }
 TIMER_OF_DECLARE(clps711x, "cirrus,ep7209-timer", clps711x_timer_init);
-- 
2.20.1