[PATCH] media: cedrus: don't initialize pointers with zero

[Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>]

A common mistake is to assume that initializing a var with:
	struct foo f = { 0 };

Would initialize a zeroed struct. Actually, what this does is
to initialize the first element of the struct to zero.

According to C99 Standard 6.7.8.21:

    "If there are fewer initializers in a brace-enclosed
     list than there are elements or members of an aggregate,
     or fewer characters in a string literal used to initialize
     an array of known size than there are elements in the array,
     the remainder of the aggregate shall be initialized implicitly
     the same as objects that have static storage duration."

So, in practice, it could zero the entire struct, but, if the
first element is not an integer, it will produce warnings:

	drivers/staging/media/sunxi/cedrus/cedrus.c:drivers/staging/media/sunxi/cedrus/cedrus.c:78:49:  warning: Using plain integer as NULL pointer
	drivers/staging/media/sunxi/cedrus/cedrus_dec.c:drivers/staging/media/sunxi/cedrus/cedrus_dec.c:29:35:  warning: Using plain integer as NULL pointer

A proper way to initialize it with gcc is to use:

	struct foo f = { };

But that seems to be a gcc extension. So, I decided to check upstream
what's the most commonly pattern. The gcc pattern has about 2000 entries:

	$ git grep -E "=\s*\{\s*\}"|wc -l
	1951

The standard-C compliant pattern has about 2500 entries:

	$ git grep -E "=\s*\{\s*NULL\s*\}"|wc -l
	137
	$ git grep -E "=\s*\{\s*0\s*\}"|wc -l
	2323

So, let's initialize those structs with:
	 = { NULL }

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
---
 drivers/staging/media/sunxi/cedrus/cedrus.c     | 2 +-
 drivers/staging/media/sunxi/cedrus/cedrus_dec.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.c b/drivers/staging/media/sunxi/cedrus/cedrus.c
index b538eb0321d8..44c45c687503 100644
--- a/drivers/staging/media/sunxi/cedrus/cedrus.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus.c
@@ -75,7 +75,7 @@ static int cedrus_init_ctrls(struct cedrus_dev *dev, struct cedrus_ctx *ctx)
 	memset(ctx->ctrls, 0, ctrl_size);
 
 	for (i = 0; i < CEDRUS_CONTROLS_COUNT; i++) {
-		struct v4l2_ctrl_config cfg = { 0 };
+		struct v4l2_ctrl_config cfg = { NULL };
 
 		cfg.elem_size = cedrus_controls[i].elem_size;
 		cfg.id = cedrus_controls[i].id;
diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_dec.c b/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
index e40180a33951..4099a42dba2d 100644
--- a/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
@@ -26,7 +26,7 @@ void cedrus_device_run(void *priv)
 {
 	struct cedrus_ctx *ctx = priv;
 	struct cedrus_dev *dev = ctx->dev;
-	struct cedrus_run run = { 0 };
+	struct cedrus_run run = { NULL };
 	struct media_request *src_req;
 	unsigned long flags;
 
-- 
2.19.2

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