linux-kernel - [PATCH -mm] uvesafb: Don't access VGA registers directly when running on non-x86

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Date:	Wed, 12 Sep 2007 21:41:51 +0200
From:	Michal Januszewski <spock@...too.org>
To:	Paul Mundt <lethal@...ux-sh.org>,
	Paulo Marques <pmarques@...popie.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org
Subject: [PATCH -mm] uvesafb: Don't access VGA registers directly when
	running on non-x86

The VGA registers are only available at their legacy IO locations on
x86. Don't try to access them when running on other arches.

Note that the code accessing them directly is just an optimization
(limits slow BIOS function calls).  We don't lose any functionality 
by using BIOS calls instead of it on non-x86.

Signed-off-by: Michal Januszewski <spock@...too.org>
---
diff --git a/drivers/video/uvesafb.c b/drivers/video/uvesafb.c
index 853323e..b983d26 100644
--- a/drivers/video/uvesafb.c
+++ b/drivers/video/uvesafb.c
@@ -19,8 +19,10 @@
 #include <linux/io.h>
 #include <linux/mutex.h>
 #include <video/edid.h>
-#include <video/vga.h>
 #include <video/uvesafb.h>
+#ifdef CONFIG_X86
+#include <video/vga.h>
+#endif
 #ifdef CONFIG_MTRR
 #include <asm/mtrr.h>
 #endif
@@ -935,6 +937,7 @@ static int uvesafb_setpalette(struct uvesafb_pal_entry *entries, int count,
 	if (start + count > 256)
 		return -EINVAL;
 
+#ifdef CONFIG_X86
 	/* Use VGA registers if mode is VGA-compatible. */
 	if (i >= 0 && i < par->vbe_modes_cnt &&
 	    par->vbe_modes[i].mode_attr & VBE_MODE_VGACOMPAT) {
@@ -957,8 +960,10 @@ static int uvesafb_setpalette(struct uvesafb_pal_entry *entries, int count,
 		  "D" (entries),        /* EDI */
 		  "S" (&par->pmi_pal)); /* ESI */
 	}
-#endif
-	else {
+#endif /* CONFIG_X86_32 */
+	else
+#endif /* CONFIG_X86 */
+	{
 		task = uvesafb_prep();
 		if (!task)
 			return -ENOMEM;
@@ -1102,6 +1107,7 @@ static int uvesafb_blank(int blank, struct fb_info *info)
 	struct uvesafb_ktask *task;
 	int err = 1;
 
+#ifdef CONFIG_X86
 	if (par->vbe_ib.capabilities & VBE_CAP_VGACOMPAT) {
 		int loop = 10000;
 		u8 seq = 0, crtc17 = 0;
@@ -1124,7 +1130,9 @@ static int uvesafb_blank(int blank, struct fb_info *info)
 		while (loop--);
 		vga_wcrt(NULL, 0x17, crtc17);
 		vga_wseq(NULL, 0x00, 0x03);
-	} else {
+	} else
+#endif /* CONFIG_X86 */
+	{
 		task = uvesafb_prep();
 		if (!task)
 			return -ENOMEM;

-
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