From 9c2332f1376f5fb7c87f16dff77e9270eb7c91c8 Mon Sep 17 00:00:00 2001
From: Matt Porter <mporter@ti.com>
Date: Tue, 22 Nov 2011 10:48:32 -0500
Subject: [PATCH 3/3] st7735fb: Make FB native endian on little endian platforms

This is a quick unoptimized implementation of a shadow swap buffer
which is engaged on little endian platforms. It's not DMA safe
at this point nor is it particularly optimized during updates.
This is ok atm since the point is to be compatible with all the
user space code out there that assumes that all FBdevs are native
endian.

Now things like "cat foo.rgb565 > /dev/fb0" work as well as standard
apps like fbv with no byte swapping mods.

Signed-off-by: Matt Porter <mporter@ti.com>
Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>
---
 drivers/video/st7735fb.c |   26 ++++++++++++++++++++------
 include/video/st7735fb.h |    1 +
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/video/st7735fb.c b/drivers/video/st7735fb.c
index 500cc88..69ad3d0 100644
--- drivers.old/video/st7735fb.c
+++ drivers/video/st7735fb.c
@@ -244,7 +244,14 @@ static void st7735fb_update_display(struct st7735fb_par *par)
 {
 	int ret = 0;
 	u8 *vmem = par->info->screen_base;
+#ifdef __LITTLE_ENDIAN
+	int i;
+	u16 *vmem16 = (u16 *)vmem;
+	u16 *ssbuf = par->ssbuf;
 
+	for (i=0; i<WIDTH*HEIGHT*BPP/8/2; i++)
+		ssbuf[i] = swab16(vmem16[i]);
+#endif
 	/*
 		TODO:
 		Allow a subset of pages to be passed in
@@ -261,7 +268,11 @@ static void st7735fb_update_display(struct st7735fb_par *par)
 	st7735_write_cmd(par, ST7735_RAMWR);
 
 	/* Blast framebuffer to ST7735 internal display RAM */
+#ifdef __LITTLE_ENDIAN
+	ret = st7735_write_data_buf(par, (u8 *)ssbuf, WIDTH*HEIGHT*BPP/8);
+#else
 	ret = st7735_write_data_buf(par, vmem, WIDTH*HEIGHT*BPP/8);
+#endif
 	if (ret < 0)
 		pr_err("%s: spi_write failed to update display buffer\n",
 			par->info->fix.id);
@@ -417,12 +428,7 @@ static int __devinit st7735fb_probe (struct spi_device *spi)
 	info->var.blue.length = 5;
 	info->var.transp.offset = 0;
 	info->var.transp.length = 0;
-	info->flags = FBINFO_FLAG_DEFAULT |
-#ifdef __LITTLE_ENDIAN
-			FBINFO_FOREIGN_ENDIAN |
-#endif
-			FBINFO_VIRTFB;
-
+	info->flags = FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB;
 	info->fbdefio = &st7735fb_defio;
 	fb_deferred_io_init(info);
 
@@ -432,6 +438,14 @@ static int __devinit st7735fb_probe (struct spi_device *spi)
 	par->rst = pdata->rst_gpio;
 	par->dc = pdata->dc_gpio;
 
+#ifdef __LITTLE_ENDIAN
+	/* Allocate swapped shadow buffer */
+	vmem = vzalloc(vmem_size);
+	if (!vmem)
+		return retval;
+	par->ssbuf = vmem;
+#endif
+
 	retval = register_framebuffer(info);
 	if (retval < 0)
 		goto fbreg_fail;
diff --git a/include/video/st7735fb.h b/include/video/st7735fb.h
index 250f036..52f5182 100644
--- include.orig/video/st7735fb.h
+++ include/video/st7735fb.h
@@ -34,6 +34,7 @@ enum st7735_cmd {
 struct st7735fb_par {
 	struct spi_device *spi;
 	struct fb_info *info;
+	u16 *ssbuf;
 	int rst;
 	int dc;
 };
-- 
1.7.2.5