2017-12-23 07:56:47

by Sean Wang

Subject: [PATCH] clk: mediatek: Fix all warnings for missing struct clk_onecell_data

From: Sean Wang <[email protected]>

In fact, the clk-mtk.h header is unnecessary for reset.c and thus it's
safe to remove it from the file to get rid of below build warnings.

All warnings (new ones prefixed by >>):

In file included from drivers/clk/mediatek/reset.c:22:0:
>>drivers/clk/mediatek/clk-mtk.h:44:19: warning: 'struct clk_onecell_data'
declared inside parameter list will not be visible outside of
this definition or declaration
int num, struct clk_onecell_data *clk_data);
^~~~~~~~~~~~~~~~
drivers/clk/mediatek/clk-mtk.h:63:19: warning: 'struct clk_onecell_data'
declared inside parameter list will not be visible outside of
this definition or declaration
int num, struct clk_onecell_data *clk_data);
^~~~~~~~~~~~~~~~
drivers/clk/mediatek/clk-mtk.h:145:10: warning: 'struct clk_onecell_data'
declared inside parameter list will not be visible outside of
this definition or declaration
struct clk_onecell_data *clk_data);
^~~~~~~~~~~~~~~~
drivers/clk/mediatek/clk-mtk.h:164:11: warning: 'struct clk_onecell_data'
declared inside parameter list will not be visible outside of
this definition or declaration
struct clk_onecell_data *clk_data);
^~~~~~~~~~~~~~~~
drivers/clk/mediatek/clk-mtk.h:190:12: warning: 'struct clk_onecell_data'
declared inside parameter list will not be visible outside of this
definition or declaration
struct clk_onecell_data *clk_data);
^~~~~~~~~~~~~~~~

Reported-by: kbuild test robot <[email protected]>
Signed-off-by: Sean Wang <[email protected]>
Cc: [email protected]
Cc: Stephen Boyd <[email protected]>
Cc: [email protected]
---
drivers/clk/mediatek/reset.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/drivers/clk/mediatek/reset.c b/drivers/clk/mediatek/reset.c
index d3551d5..70ebb2e 100644
--- a/drivers/clk/mediatek/reset.c
+++ b/drivers/clk/mediatek/reset.c
@@ -19,8 +19,6 @@
#include <linux/reset-controller.h>
#include <linux/slab.h>

-#include "clk-mtk.h"
-
struct mtk_reset {
struct regmap *regmap;
int regofs;
--
2.7.4

2017-12-23 11:20:09

by Jean Delvare

Subject: Re: [PATCH] clk: mediatek: Fix all warnings for missing struct clk_onecell_data

Hi Sean,

On Sat, 23 Dec 2017 15:56:36 +0800, [email protected] wrote:
> From: Sean Wang <[email protected]>
>
> In fact, the clk-mtk.h header is unnecessary for reset.c and thus it's
> safe to remove it from the file to get rid of below build warnings.
>
> All warnings (new ones prefixed by >>):
>
> In file included from drivers/clk/mediatek/reset.c:22:0:
> >>drivers/clk/mediatek/clk-mtk.h:44:19: warning: 'struct clk_onecell_data'
> declared inside parameter list will not be visible outside of
> this definition or declaration
> int num, struct clk_onecell_data *clk_data);
> ^~~~~~~~~~~~~~~~
> drivers/clk/mediatek/clk-mtk.h:63:19: warning: 'struct clk_onecell_data'
> declared inside parameter list will not be visible outside of
> this definition or declaration
> int num, struct clk_onecell_data *clk_data);
> ^~~~~~~~~~~~~~~~
> drivers/clk/mediatek/clk-mtk.h:145:10: warning: 'struct clk_onecell_data'
> declared inside parameter list will not be visible outside of
> this definition or declaration
> struct clk_onecell_data *clk_data);
> ^~~~~~~~~~~~~~~~
> drivers/clk/mediatek/clk-mtk.h:164:11: warning: 'struct clk_onecell_data'
> declared inside parameter list will not be visible outside of
> this definition or declaration
> struct clk_onecell_data *clk_data);
> ^~~~~~~~~~~~~~~~
> drivers/clk/mediatek/clk-mtk.h:190:12: warning: 'struct clk_onecell_data'
> declared inside parameter list will not be visible outside of this
> definition or declaration
> struct clk_onecell_data *clk_data);
> ^~~~~~~~~~~~~~~~

That's not the proper fix. The actual problem here is in clk-mtk.h,
which declares functions which need struct clk_onecell_data without
declaring that structure first. This can be fixed in 2 ways:

1* #Include whatever header file provides the definition of struct
clk_onecell_data (I think <linux/clk-provider.h>) in clk-mtk.h
itself.

2* As you only manipulate pointers and not the structure itself, you
could simply declare that this struct exists, without defining it,
prior to referencing it in clk-mtk.h. As easy as:

struct clk_onecell_data;

In this case option 1 seems preferable.

The reason why the problem is only visible in reset.c is because other
source files under drivers/clk/mediatek #include <linux/clk-provider.h>
explicitly before #including clk-mtk.h. But it only works "by
accident". Ideally header files should be self-sufficient, so you don't
depend on #include order.

> Reported-by: kbuild test robot <[email protected]>
> Signed-off-by: Sean Wang <[email protected]>
> Cc: [email protected]
> Cc: Stephen Boyd <[email protected]>
> Cc: [email protected]
> ---
> drivers/clk/mediatek/reset.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/drivers/clk/mediatek/reset.c b/drivers/clk/mediatek/reset.c
> index d3551d5..70ebb2e 100644
> --- a/drivers/clk/mediatek/reset.c
> +++ b/drivers/clk/mediatek/reset.c
> @@ -19,8 +19,6 @@
> #include <linux/reset-controller.h>
> #include <linux/slab.h>
>
> -#include "clk-mtk.h"
> -
> struct mtk_reset {
> struct regmap *regmap;
> int regofs;

If the header file is indeed not needed then that's still a good
change, even if it doesn't fix the problem, so:

Reviewed-by: Jean Delvare <[email protected]>

However the patch description should be adjusted accordingly.

--
Jean Delvare
SUSE L3 Support

2017-12-23 15:47:31

by Sean Wang

Subject: Re: [PATCH] clk: mediatek: Fix all warnings for missing struct clk_onecell_data

On Sat, 2017-12-23 at 12:20 +0100, Jean Delvare wrote:
> Hi Sean,
>
> On Sat, 23 Dec 2017 15:56:36 +0800, [email protected] wrote:
> > From: Sean Wang <[email protected]>
> >
> > In fact, the clk-mtk.h header is unnecessary for reset.c and thus it's
> > safe to remove it from the file to get rid of below build warnings.
> >
> > All warnings (new ones prefixed by >>):
> >
> > In file included from drivers/clk/mediatek/reset.c:22:0:
> > >>drivers/clk/mediatek/clk-mtk.h:44:19: warning: 'struct clk_onecell_data'
> > declared inside parameter list will not be visible outside of
> > this definition or declaration
> > int num, struct clk_onecell_data *clk_data);
> > ^~~~~~~~~~~~~~~~
> > drivers/clk/mediatek/clk-mtk.h:63:19: warning: 'struct clk_onecell_data'
> > declared inside parameter list will not be visible outside of
> > this definition or declaration
> > int num, struct clk_onecell_data *clk_data);
> > ^~~~~~~~~~~~~~~~
> > drivers/clk/mediatek/clk-mtk.h:145:10: warning: 'struct clk_onecell_data'
> > declared inside parameter list will not be visible outside of
> > this definition or declaration
> > struct clk_onecell_data *clk_data);
> > ^~~~~~~~~~~~~~~~
> > drivers/clk/mediatek/clk-mtk.h:164:11: warning: 'struct clk_onecell_data'
> > declared inside parameter list will not be visible outside of
> > this definition or declaration
> > struct clk_onecell_data *clk_data);
> > ^~~~~~~~~~~~~~~~
> > drivers/clk/mediatek/clk-mtk.h:190:12: warning: 'struct clk_onecell_data'
> > declared inside parameter list will not be visible outside of this
> > definition or declaration
> > struct clk_onecell_data *clk_data);
> > ^~~~~~~~~~~~~~~~
>
> That's not the proper fix. The actual problem here is in clk-mtk.h,
> which declares functions which need struct clk_onecell_data without
> declaring that structure first. This can be fixed in 2 ways:
>
> 1* #Include whatever header file provides the definition of struct
> clk_onecell_data (I think <linux/clk-provider.h>) in clk-mtk.h
> itself.
>
> 2* As you only manipulate pointers and not the structure itself, you
> could simply declare that this struct exists, without defining it,
> prior to referencing it in clk-mtk.h. As easy as:
>
> struct clk_onecell_data;
>
> In this case option 1 seems preferable.
>
> The reason why the problem is only visible in reset.c is because other
> source files under drivers/clk/mediatek #include <linux/clk-provider.h>
> explicitly before #including clk-mtk.h. But it only works "by
> accident". Ideally header files should be self-sufficient, so you don't
> depend on #include order.
>

agreed on above. I also prefer using option 1 to solve original issue.

> > Reported-by: kbuild test robot <[email protected]>
> > Signed-off-by: Sean Wang <[email protected]>
> > Cc: [email protected]
> > Cc: Stephen Boyd <[email protected]>
> > Cc: [email protected]
> > ---
> > drivers/clk/mediatek/reset.c | 2 --
> > 1 file changed, 2 deletions(-)
> >
> > diff --git a/drivers/clk/mediatek/reset.c b/drivers/clk/mediatek/reset.c
> > index d3551d5..70ebb2e 100644
> > --- a/drivers/clk/mediatek/reset.c
> > +++ b/drivers/clk/mediatek/reset.c
> > @@ -19,8 +19,6 @@
> > #include <linux/reset-controller.h>
> > #include <linux/slab.h>
> >
> > -#include "clk-mtk.h"
> > -
> > struct mtk_reset {
> > struct regmap *regmap;
> > int regofs;
>
> If the header file is indeed not needed then that's still a good
> change, even if it doesn't fix the problem, so:
>
> Reviewed-by: Jean Delvare <[email protected]>

> However the patch description should be adjusted accordingly.


I will use another patch to remove the indeed not needed header

thanks a lot for your detailed explanation and help

Sean