[PATCH 2/3] [FBDEV]: Video mode change notify (fbset)

["Antonino A. Daplas" <adaplas@hotpop.com>]

Hi,

This patch allows fbset to change the video mode and the console
window size via the notifier call chain.  It will only notify fbcon of
mode changes from user space.  Changes coming from
upstream will be ignored.

The code will only update the current console.

Tony

Against linux-2.6.7-mm1

Signed-off-by: Antonino Daplas <adaplas@pol.net>

diff -Naur linux-2.6.7-mm1-orig/drivers/video/console/fbcon.c linux-2.6.7-mm1/drivers/video/console/fbcon.c
--- linux-2.6.7-mm1-orig/drivers/video/console/fbcon.c	2004-06-21 16:49:22.000000000 +0000
+++ linux-2.6.7-mm1/drivers/video/console/fbcon.c	2004-06-21 17:12:20.896035296 +0000
@@ -2358,6 +2358,56 @@
 	update_screen(vc->vc_num);
 }
 
+static void fbcon_modechanged(struct fb_info *info)
+{
+	struct vc_data *vc = vc_cons[info->currcon].d;
+	struct display *p;
+	int rows, cols;
+
+	if (info->currcon < 0 || vt_cons[info->currcon]->vc_mode !=
+	    KD_TEXT) 
+		return;
+	p = &fb_display[vc->vc_num];
+
+	info->var.xoffset = info->var.yoffset = p->yscroll = 0;
+	vc->vc_can_do_color = info->var.bits_per_pixel != 1;
+	vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
+
+	if (CON_IS_VISIBLE(vc)) {
+		cols = info->var.xres / vc->vc_font.width;
+		rows = info->var.yres / vc->vc_font.height;
+		vc_resize(vc->vc_num, cols, rows);
+		switch (p->scrollmode) {
+		case SCROLL_WRAP:
+			scrollback_phys_max = p->vrows - vc->vc_rows;
+			break;
+		case SCROLL_PAN:
+			scrollback_phys_max = p->vrows - 2 * vc->vc_rows;
+			if (scrollback_phys_max < 0)
+				scrollback_phys_max = 0;
+			break;
+		default:
+			scrollback_phys_max = 0;
+			break;
+		}	
+		scrollback_max = 0;
+		scrollback_current = 0;
+		update_var(vc->vc_num, info);
+		fbcon_set_palette(vc, color_table); 	
+		update_screen(vc->vc_num);
+		if (softback_buf) { 
+			int l = fbcon_softback_size / vc->vc_size_row;
+			if (l > 5)
+				softback_end = softback_buf + l * vc->vc_size_row;
+			else {
+				/* Smaller scrollback makes no sense, and 0 
+				   would screw the operation totally */
+				softback_top = 0;
+			}
+		}
+	}
+}
+
 static int fbcon_event_notify(struct notifier_block *self, 
 			      unsigned long action, void *data)
 {
@@ -2370,6 +2420,9 @@
 	case FB_EVENT_RESUME:
 		fbcon_resumed(info);
 		break;
+	case FB_EVENT_MODE_CHANGE:
+		fbcon_modechanged(info);
+		break;
 	}
 	    
 	return 0;
diff -Naur linux-2.6.7-mm1-orig/drivers/video/fbmem.c linux-2.6.7-mm1/drivers/video/fbmem.c
--- linux-2.6.7-mm1-orig/drivers/video/fbmem.c	2004-06-21 16:49:22.000000000 +0000
+++ linux-2.6.7-mm1/drivers/video/fbmem.c	2004-06-21 17:12:07.429082584 +0000
@@ -1005,7 +1005,11 @@
 
 			fb_set_cmap(&info->cmap, 1, info);
 
-			notifier_call_chain(&fb_notifier_list, FB_EVENT_MODE_CHANGE, info);
+			if (info->flags & FBINFO_MISC_MODECHANGEUSER) {
+				notifier_call_chain(&fb_notifier_list, 
+						    FB_EVENT_MODE_CHANGE, info);
+				info->flags &= ~FBINFO_MISC_MODECHANGEUSER;
+			}
 		}
 	}
 	return 0;
@@ -1056,7 +1060,9 @@
 		if (copy_from_user(&var, (void *) arg, sizeof(var)))
 			return -EFAULT;
 		acquire_console_sem();
+		info->flags |= FBINFO_MISC_MODECHANGEUSER;
 		i = fb_set_var(info, &var);
+		info->flags &= ~FBINFO_MISC_MODECHANGEUSER;
 		release_console_sem();
 		if (i) return i;
 		if (copy_to_user((void *) arg, &var, sizeof(var)))
diff -Naur linux-2.6.7-mm1-orig/include/linux/fb.h linux-2.6.7-mm1/include/linux/fb.h
--- linux-2.6.7-mm1-orig/include/linux/fb.h	2004-06-21 16:49:23.000000000 +0000
+++ linux-2.6.7-mm1/include/linux/fb.h	2004-06-21 17:12:36.452670328 +0000
@@ -530,6 +530,8 @@
 #define FBINFO_HWACCEL_YPAN		0x2000 /* optional */
 #define FBINFO_HWACCEL_YWRAP		0x4000 /* optional */
 
+#define FBINFO_MISC_MODECHANGEUSER     0x10000 /* mode change request
+						  from userspace */
 
 struct fb_info {
 	int node;




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