fbdev/ps3fb: Initialize fb_ops with fbdev macros

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

Fbdev drivers sometimes rely on the callbacks being NULL for a
default I/O-memory-based 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.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231127131655.4020-20-tzimmermann@suse.de

drivers/video/fbdev/Kconfig

@@ -1715,10 +1715,7 @@ config FB_IBM_GXT4500
 config FB_PS3
 	tristate "PS3 GPU framebuffer driver"
 	depends on FB && PS3_PS3AV
-	select FB_SYS_FILLRECT
-	select FB_SYS_COPYAREA
-	select FB_SYS_IMAGEBLIT
-	select FB_SYS_FOPS
+	select FB_SYSMEM_HELPERS
 	help
 	  Include support for the virtual frame buffer in the PS3 platform.
 

drivers/video/fbdev/ps3fb.c

@@ -939,15 +939,12 @@ static const struct fb_ops ps3fb_ops = {
 	.owner		= THIS_MODULE,
 	.fb_open	= ps3fb_open,
 	.fb_release	= ps3fb_release,
-	.fb_read        = fb_sys_read,
-	.fb_write       = fb_sys_write,
+	__FB_DEFAULT_SYSMEM_OPS_RDWR,
 	.fb_check_var	= ps3fb_check_var,
 	.fb_set_par	= ps3fb_set_par,
 	.fb_setcolreg	= ps3fb_setcolreg,
 	.fb_pan_display	= ps3fb_pan_display,
-	.fb_fillrect	= sys_fillrect,
-	.fb_copyarea	= sys_copyarea,
-	.fb_imageblit	= sys_imageblit,
+	__FB_DEFAULT_SYSMEM_OPS_DRAW,
 	.fb_mmap	= ps3fb_mmap,
 	.fb_blank	= ps3fb_blank,
 	.fb_ioctl	= ps3fb_ioctl,