[PATCH] radeonfb: Add quirk for the graphics adapter in some JSxx

[olaf at aepfle.de]

From: Tony Breeds <tony at bakeyournoodle.com>

These devices are set to 640x480 by firmware, switch them to 800x600 at 60
so that the graphical installer can run on remote console.

Reported by IBM during SLES10 SP2 beta testing:

https://bugzilla.novell.com/show_bug.cgi?id=461002
LTC50817

Signed-off-by: Olaf Hering <olaf at aepfle.de>

diff --git a/drivers/video/aty/radeon_monitor.c b/drivers/video/aty/radeon_monitor.c
index 9261c91..5c23eac 100644
--- a/drivers/video/aty/radeon_monitor.c
+++ b/drivers/video/aty/radeon_monitor.c
@@ -730,6 +730,25 @@ static void radeon_videomode_to_var(struct fb_var_screeninfo *var,
 	var->vmode = mode->vmode;
 }
 
+#ifdef CONFIG_PPC_PSERIES
+static int is_powerblade(const char *model)
+{
+	struct device_node *root;
+	const char* cp;
+	int len, l, rc = 0;
+
+	root = of_find_node_by_path("/");
+	if (root && model) {
+		l = strlen(model);
+		cp = of_get_property(root, "model", &len);
+		if (cp)
+			rc = memcmp(model, cp, min(len, l)) == 0;
+		of_node_put(root);
+	}
+	return rc;
+}
+#endif
+
 /*
  * Build the modedb for head 1 (head 2 will come later), check panel infos
  * from either BIOS or EDID, and pick up the default mode
@@ -865,6 +884,22 @@ void __devinit radeon_check_modes(struct radeonfb_info *rinfo, const char *mode_
 			has_default_mode = 1;
  	}
 
+#ifdef CONFIG_PPC_PSERIES
+	if (!has_default_mode && (
+		is_powerblade("IBM,8842") || /* JS20 */
+		is_powerblade("IBM,8844") || /* JS21 */
+		is_powerblade("IBM,7998") || /* JS12/JS21/JS22 */
+		is_powerblade("IBM,0792") || /* QS21 */
+		is_powerblade("IBM,0793")    /* QS22 */
+	    )) {
+		printk("Falling back to 800x600 on JSxx hardware\n");
+		if (fb_find_mode(&info->var, info, "800x600 at 60",
+				 info->monspecs.modedb,
+				 info->monspecs.modedb_len, NULL, 8) != 0)
+			has_default_mode = 1;
+	}
+#endif
+
 	/*
 	 * Still no mode, let's pick up a default from the db
 	 */
-- 
1.7.10.4