Re: [linux-next:master 11942/12503] drivers/video/fbdev/aty/atyfb_base.c:180:6: warning: no previous prototype for function 'aty_st_lcd'

[Randy Dunlap <rdunlap@infradead.org>]

On 2/24/21 4:46 AM, kernel test robot wrote:
> Hi Randy,
> 
> FYI, the error/warning still remains.
> 
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   577c283560fe8a81a23a95654c6d13e8412d22f1
> commit: bfa5782b9caa26f93f42ad79804e1f75a1ce9f18 [11942/12503] fbdev: atyfb: add stubs for aty_{ld,st}_lcd()
> config: arm64-randconfig-r004-20210223 (attached as .config)
> compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project f14a14dd2564703db02f80c00db8ae492b594f77)
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install arm64 cross compiling tool for clang build
>         # apt-get install binutils-aarch64-linux-gnu
>         # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=bfa5782b9caa26f93f42ad79804e1f75a1ce9f18
>         git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>         git fetch --no-tags linux-next master
>         git checkout bfa5782b9caa26f93f42ad79804e1f75a1ce9f18
>         # save the attached .config to linux build tree
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
> 
> All warnings (new ones prefixed by >>):
> 
>>> drivers/video/fbdev/aty/atyfb_base.c:180:6: warning: no previous prototype for function 'aty_st_lcd' [-Wmissing-prototypes]
>    void aty_st_lcd(int index, u32 val, const struct atyfb_par *par)
>         ^
>    drivers/video/fbdev/aty/atyfb_base.c:180:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
>    void aty_st_lcd(int index, u32 val, const struct atyfb_par *par)
>    ^
>    static 
>>> drivers/video/fbdev/aty/atyfb_base.c:183:5: warning: no previous prototype for function 'aty_ld_lcd' [-Wmissing-prototypes]
>    u32 aty_ld_lcd(int index, const struct atyfb_par *par)
>        ^
>    drivers/video/fbdev/aty/atyfb_base.c:183:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
>    u32 aty_ld_lcd(int index, const struct atyfb_par *par)
>    ^
>    static 
>    2 warnings generated.
> 

These 2 functions are also used/usable (depending on CONFIG options) in
mach64_ct.c so they can't be static.

AFAIK, we don't make functions have different qualifiers depending on
config options.

> 
> vim +/aty_st_lcd +180 drivers/video/fbdev/aty/atyfb_base.c
> 
>    163	
>    164	u32 aty_ld_lcd(int index, const struct atyfb_par *par)
>    165	{
>    166		if (M64_HAS(LT_LCD_REGS)) {
>    167			return aty_ld_le32(lt_lcd_regs[index], par);
>    168		} else {
>    169			unsigned long temp;
>    170	
>    171			/* write addr byte */
>    172			temp = aty_ld_le32(LCD_INDEX, par);
>    173			aty_st_le32(LCD_INDEX, (temp & ~LCD_INDEX_MASK) | index, par);
>    174			/* read the register value */
>    175			return aty_ld_le32(LCD_DATA, par);
>    176		}
>    177	}
>    178	#else /* defined(CONFIG_PMAC_BACKLIGHT) || defined(CONFIG_FB_ATY_BACKLIGHT) \
>    179		 defined(CONFIG_FB_ATY_GENERIC_LCD) */
>  > 180	void aty_st_lcd(int index, u32 val, const struct atyfb_par *par)
>    181	{ }
>    182	
>  > 183	u32 aty_ld_lcd(int index, const struct atyfb_par *par)
>    184	{
>    185		return 0;
>    186	}
>    187	#endif /* defined(CONFIG_PMAC_BACKLIGHT) || defined (CONFIG_FB_ATY_GENERIC_LCD) */
>    188	
> 
> ---


-- 
~Randy