fbdev/hitfb: 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/20230927074722.6197-18-tzimmermann@suse.de

drivers/video/fbdev/Kconfig

@@ -1490,8 +1490,8 @@ config FB_HIT
 	tristate "HD64461 Frame Buffer support"
 	depends on FB && HD64461
 	select FB_CFB_FILLRECT
-	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT
+	select FB_IOMEM_FOPS
 	help
 	  This is the frame buffer device driver for the Hitachi HD64461 LCD
 	  frame buffer card.

drivers/video/fbdev/hitfb.c

@@ -328,6 +328,7 @@ static int hitfb_set_par(struct fb_info *info)
 
 static const struct fb_ops hitfb_ops = {
 	.owner		= THIS_MODULE,
+	__FB_DEFAULT_IOMEM_OPS_RDWR,
 	.fb_check_var	= hitfb_check_var,
 	.fb_set_par	= hitfb_set_par,
 	.fb_setcolreg	= hitfb_setcolreg,
@@ -337,6 +338,7 @@ static const struct fb_ops hitfb_ops = {
 	.fb_fillrect	= hitfb_fillrect,
 	.fb_copyarea	= hitfb_copyarea,
 	.fb_imageblit	= cfb_imageblit,
+	__FB_DEFAULT_IOMEM_OPS_MMAP,
 };
 
 static int hitfb_probe(struct platform_device *dev)