[PATCH v4] ARM: w90x900: let clk_disable() return immediately if clk is NULL

In many of clk_disable() implementations, it is a no-op for a NULL
pointer input, but this is one of the exceptions.

Making it treewide consistent will allow clock consumers to call
clk_disable() without NULL pointer check.

Signed-off-by: Masahiro Yamada <redacted>
Acked-by: Wan Zongshun <redacted>
---

Changes in v4:
  - Split into per-arch patches

Changes in v3:
  - Return only when clk is NULL.  Do not take care of error pointer.

Changes in v2:
  - Rebase on Linux 4.6-rc1

 arch/arm/mach-w90x900/clock.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm/mach-w90x900/clock.c b/arch/arm/mach-w90x900/clock.c
index 2c371ff..ac6fd1a 100644
--- a/arch/arm/mach-w90x900/clock.c
+++ b/arch/arm/mach-w90x900/clock.c

@@ -46,6 +46,9 @@ void clk_disable(struct clk *clk)
 {
 	unsigned long flags;
 
+	if (!clk)
+		return;
+
 	WARN_ON(clk->enabled == 0);
 
 	spin_lock_irqsave(&clocks_lock, flags);

-- 
1.9.1