fbdev/68328fb: Initialize fb_ops to fbdev I/O-memory helpers

Initialize the instance of struct fb_ops with fbdev initializer
macros for framebuffers in I/O address space. Set the read/write,
draw and mmap callbacks to the correct implementation and avoid
implicit defaults. Also select the necessary I/O helpers in Kconfig.

Fbdev drivers sometimes rely on the callbacks being NULL for a
default implementation to be invoked; hence requiring the I/O
helpers to be built in any case. Setting all callbacks in all
drivers explicitly will allow to make the I/O helpers optional.
This benefits systems that do not use these functions.

No functional changes.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230927074722.6197-3-tzimmermann@suse.de

drivers/video/fbdev/68328fb.c

@@ -95,13 +95,12 @@ static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma);
 
 static const struct fb_ops mc68x328fb_ops = {
 	.owner		= THIS_MODULE,
+	__FB_DEFAULT_IOMEM_OPS_RDWR,
 	.fb_check_var	= mc68x328fb_check_var,
 	.fb_set_par	= mc68x328fb_set_par,
 	.fb_setcolreg	= mc68x328fb_setcolreg,
 	.fb_pan_display	= mc68x328fb_pan_display,
-	.fb_fillrect	= cfb_fillrect,
-	.fb_copyarea	= cfb_copyarea,
-	.fb_imageblit	= cfb_imageblit,
+	__FB_DEFAULT_IOMEM_OPS_DRAW,
 	.fb_mmap	= mc68x328fb_mmap,
 };
 

drivers/video/fbdev/Kconfig

@@ -1541,9 +1541,7 @@ config FB_G364
 config FB_68328
 	bool "Motorola 68328 native frame buffer support"
 	depends on (FB = y) && (M68328 || M68EZ328 || M68VZ328)
-	select FB_CFB_FILLRECT
-	select FB_CFB_COPYAREA
-	select FB_CFB_IMAGEBLIT
+	select FB_IOMEM_HELPERS
 	help
 	  Say Y here if you want to support the built-in frame buffer of
 	  the Motorola 68328 CPU family.