Fixed MTP to work with TWRP

arch/x86/kernel/sysfb_simplefb.c

@@ -0,0 +1,95 @@
+/*
+ * Generic System Framebuffers on x86
+ * Copyright (c) 2012-2013 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.
+ */
+
+/*
+ * simple-framebuffer probing
+ * Try to convert "screen_info" into a "simple-framebuffer" compatible mode.
+ * If the mode is incompatible, we return "false" and let the caller create
+ * legacy nodes instead.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/platform_data/simplefb.h>
+#include <linux/platform_device.h>
+#include <linux/screen_info.h>
+#include <asm/sysfb.h>
+
+static const char simplefb_resname[] = "BOOTFB";
+static const struct simplefb_format formats[] = SIMPLEFB_FORMATS;
+
+/* try parsing x86 screen_info into a simple-framebuffer mode struct */
+__init bool parse_mode(const struct screen_info *si,
+		       struct simplefb_platform_data *mode)
+{
+	const struct simplefb_format *f;
+	__u8 type;
+	unsigned int i;
+
+	type = si->orig_video_isVGA;
+	if (type != VIDEO_TYPE_VLFB && type != VIDEO_TYPE_EFI)
+		return false;
+
+	for (i = 0; i < ARRAY_SIZE(formats); ++i) {
+		f = &formats[i];
+		if (si->lfb_depth == f->bits_per_pixel &&
+		    si->red_size == f->red.length &&
+		    si->red_pos == f->red.offset &&
+		    si->green_size == f->green.length &&
+		    si->green_pos == f->green.offset &&
+		    si->blue_size == f->blue.length &&
+		    si->blue_pos == f->blue.offset &&
+		    si->rsvd_size == f->transp.length &&
+		    si->rsvd_pos == f->transp.offset) {
+			mode->format = f->name;
+			mode->width = si->lfb_width;
+			mode->height = si->lfb_height;
+			mode->stride = si->lfb_linelength;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+__init int create_simplefb(const struct screen_info *si,
+			   const struct simplefb_platform_data *mode)
+{
+	struct platform_device *pd;
+	struct resource res;
+	unsigned long len;
+
+	/* don't use lfb_size as it may contain the whole VMEM instead of only
+	 * the part that is occupied by the framebuffer */
+	len = mode->height * mode->stride;
+	len = PAGE_ALIGN(len);
+	if (len > (u64)si->lfb_size << 16) {
+		printk(KERN_WARNING "sysfb: VRAM smaller than advertised\n");
+		return -EINVAL;
+	}
+
+	/* setup IORESOURCE_MEM as framebuffer memory */
+	memset(&res, 0, sizeof(res));
+	res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+	res.name = simplefb_resname;
+	res.start = si->lfb_base;
+	res.end = si->lfb_base + len - 1;
+	if (res.end <= res.start)
+		return -EINVAL;
+
+	pd = platform_device_register_resndata(NULL, "simple-framebuffer", 0,
+					       &res, 1, mode, sizeof(*mode));
+	if (IS_ERR(pd))
+		return PTR_ERR(pd);
+
+	return 0;
+}