Re: [PATCH v3 4/4] fbdev: sh_mobile_lcdc: Make FB_DEVICE dependency optional

[Helge Deller <deller@kernel.org>]

* Chintan Patel <chintanlike@gmail.com>:
> The sh_mobile_lcdc driver exposes overlay configuration via sysfs, but the
> core driver does not require CONFIG_FB_DEVICE.
> 
> Make sysfs support optional by defining overlay_sysfs_groups conditionally
> using PTR_IF(). The driver always sets .dev_groups, and the kernel
> naturally skips NULL attribute groups while the code remains buildable
> and type-checked.
> 
> Suggested-by: Helge Deller <deller@gmx.de>
> Signed-off-by: Chintan Patel <chintanlike@gmail.com>
> ---
>  drivers/video/fbdev/sh_mobile_lcdcfb.c | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/video/fbdev/sh_mobile_lcdcfb.c b/drivers/video/fbdev/sh_mobile_lcdcfb.c
> index dd950e4ab5ce..cb7ed1ff9165 100644
> --- a/drivers/video/fbdev/sh_mobile_lcdcfb.c
> +++ b/drivers/video/fbdev/sh_mobile_lcdcfb.c
> @@ -1350,7 +1350,17 @@ static struct attribute *overlay_sysfs_attrs[] = {
>  	&dev_attr_overlay_rop3.attr,
>  	NULL,
>  };
> -ATTRIBUTE_GROUPS(overlay_sysfs);

Instead of replacing the ^ ATTRIBUTE_GROUPS() by the code below,
isn't it possible to just mark the overlay_sysfs_attrs[] array
_maybe_unused, and just do:
+ #ifdef CONFIG_FB_DEVICE
+ ATTRIBUTE_GROUPS(overlay_sysfs);
+ #endif

?

Helge


> +
> +#ifdef CONFIG_FB_DEVICE
> +static const struct attribute_group overlay_sysfs_group = {
> +	.attrs = overlay_sysfs_attrs,
> +};
> +#endif
> +
> +static const struct attribute_group *overlay_sysfs_groups[] = {
> +	PTR_IF(IS_ENABLED(CONFIG_FB_DEVICE), &overlay_sysfs_group),
> +	NULL,
> +};
>  
>  static const struct fb_fix_screeninfo sh_mobile_lcdc_overlay_fix  = {
>  	.id =		"SH Mobile LCDC",
> -- 
> 2.43.0
> 
>