fbdev/sbus: Add initializer macros and Kconfig tokens for SBUS support

Add macros to initialize struct fb_ops for drivers that support
framebuffers on Sparc's SBUS. Also add a Kconfig token that selects
the necessary helpers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230806120926.5368-4-tzimmermann@suse.de

drivers/video/fbdev/Kconfig

@@ -518,6 +518,12 @@ config FB_SBUS
 	help
 	  Say Y if you want support for SBUS or UPA based frame buffer device.
 
+config FB_SBUS_HELPERS
+	bool
+	select FB_CFB_COPYAREA
+	select FB_CFB_FILLRECT
+	select FB_CFB_IMAGEBLIT
+
 config FB_BW2
 	bool "BWtwo support"
 	depends on (FB = y) && (SPARC && FB_SBUS)

drivers/video/fbdev/sbuslib.h

@@ -29,4 +29,35 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg,
 int sbusfb_compat_ioctl(struct fb_info *info, unsigned int cmd,
 			unsigned long arg);
 
+/*
+ * Initialize struct fb_ops for SBUS I/O.
+ */
+
+#define __FB_DEFAULT_SBUS_OPS_RDWR(__prefix) \
+	.fb_read	= fb_io_read, \
+	.fb_write	= fb_io_write
+
+#define __FB_DEFAULT_SBUS_OPS_DRAW(__prefix) \
+	.fb_fillrect	= cfb_fillrect, \
+	.fb_copyarea	= cfb_copyarea, \
+	.fb_imageblit	= cfb_imageblit
+
+#ifdef CONFIG_COMPAT
+#define __FB_DEFAULT_SBUS_OPS_IOCTL(__prefix) \
+	.fb_ioctl		= __prefix ## _sbusfb_ioctl, \
+	.fb_compat_ioctl	= sbusfb_compat_ioctl
+#else
+#define __FB_DEFAULT_SBUS_OPS_IOCTL(__prefix) \
+	.fb_ioctl	= __prefix ## _sbusfb_ioctl
+#endif
+
+#define __FB_DEFAULT_SBUS_OPS_MMAP(__prefix) \
+	.fb_mmap	= __prefix ## _sbusfb_mmap
+
+#define FB_DEFAULT_SBUS_OPS(__prefix) \
+	__FB_DEFAULT_SBUS_OPS_RDWR(__prefix), \
+	__FB_DEFAULT_SBUS_OPS_DRAW(__prefix), \
+	__FB_DEFAULT_SBUS_OPS_IOCTL(__prefix), \
+	__FB_DEFAULT_SBUS_OPS_MMAP(__prefix)
+
 #endif /* _SBUSLIB_H */