fbdev: simplefb: add init through platform_data

If we create proper platform-devices in x86 boot-code, we can use simplefb
for VBE or EFI framebuffers, too. However, there is normally no OF support
so we introduce a platform_data object so x86 boot-code can pass the
parameters via plain old platform-data.

This also removes the OF dependency as it is not needed. The headers
provide proper dummies for the case OF is disabled.

Furthermore, we move the FORMAT-definitions to the common platform header
so initialization code can use it to transform "struct screen_info" to
the right format-name.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Link: http://lkml.kernel.org/r/1375445127-15480-2-git-send-email-dh.herrmann@gmail.com
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/include/linux/platform_data/simplefb.h b/include/linux/platform_data/simplefb.h
new file mode 100644
index 000000000000..5fa2c5e02ab8
--- /dev/null
+++ b/include/linux/platform_data/simplefb.h
@@ -0,0 +1,56 @@
+/*
+ * simplefb.h - Simple Framebuffer Device
+ *
+ * Copyright (C) 2013 David Herrmann <dh.herrmann@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __PLATFORM_DATA_SIMPLEFB_H__
+#define __PLATFORM_DATA_SIMPLEFB_H__
+
+#include <drm/drm_fourcc.h>
+#include <linux/fb.h>
+#include <linux/kernel.h>
+
+/* format array, use it to initialize a "struct simplefb_format" array */
+#define SIMPLEFB_FORMATS \
+{ \
+	{ "r5g6b5", 16, {11, 5}, {5, 6}, {0, 5}, {0, 0}, DRM_FORMAT_RGB565 }, \
+}
+
+/*
+ * Data-Format for Simple-Framebuffers
+ * @name: unique 0-terminated name that can be used to identify the mode
+ * @red,green,blue: Offsets and sizes of the single RGB parts
+ * @transp: Offset and size of the alpha bits. length=0 means no alpha
+ * @fourcc: 32bit DRM four-CC code (see drm_fourcc.h)
+ */
+struct simplefb_format {
+	const char *name;
+	u32 bits_per_pixel;
+	struct fb_bitfield red;
+	struct fb_bitfield green;
+	struct fb_bitfield blue;
+	struct fb_bitfield transp;
+	u32 fourcc;
+};
+
+/*
+ * Simple-Framebuffer description
+ * If the arch-boot code creates simple-framebuffers without DT support, it
+ * can pass the width, height, stride and format via this platform-data object.
+ * The framebuffer location must be given as IORESOURCE_MEM resource.
+ * @format must be a format as described in "struct simplefb_format" above.
+ */
+struct simplefb_platform_data {
+	u32 width;
+	u32 height;
+	u32 stride;
+	const char *format;
+};
+
+#endif /* __PLATFORM_DATA_SIMPLEFB_H__ */