[PATCH] fbdev: Resurrect hooks to get EDID from firmware

For the i386, code is already present in video.S that gets the EDID from the
video BIOS.  Make this visible so drivers can also use this data as fallback
when i2c does not work.

To ensure that the EDID block is returned for the primary graphics adapter
only, by check if the IORESOURCE_ROM_SHADOW flag is set.

Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 34 insertions, 1 deletions

diff --git a/drivers/video/fbmon.c b/drivers/video/fbmon.c
index c2718bb94949..791bec3d672a 100644
--- a/drivers/video/fbmon.c
+++ b/drivers/video/fbmon.c
@@ -29,6 +29,7 @@
 #include <linux/tty.h>
 #include <linux/fb.h>
 #include <linux/module.h>
+#include <video/edid.h>
 #ifdef CONFIG_PPC_OF
 #include <linux/pci.h>
 #include <asm/prom.h>
@@ -1251,9 +1252,41 @@ int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
                 -EINVAL : 0;
 }
 
+#if defined(__i386__)
+#include <linux/pci.h>
+
+/*
+ * We need to ensure that the EDID block is only returned for
+ * the primary graphics adapter.
+ */
+
+const unsigned char *fb_firmware_edid(struct device *device)
+{
+        struct pci_dev *dev = NULL;
+        struct resource *res = NULL;
+        unsigned char *edid = NULL;
+
+        if (device)
+                dev = to_pci_dev(device);
+
+        if (dev)
+                res = &dev->resource[PCI_ROM_RESOURCE];
+
+        if (res && res->flags & IORESOURCE_ROM_SHADOW)
+                edid = edid_info.dummy;
+
+        return edid;
+}
+#else
+const unsigned char *fb_firmware_edid(struct device *device)
+{
+        return NULL;
+}
+#endif /* _i386_ */
+
 EXPORT_SYMBOL(fb_parse_edid);
 EXPORT_SYMBOL(fb_edid_to_monspecs);
-
+EXPORT_SYMBOL(fb_firmware_edid);
 EXPORT_SYMBOL(fb_get_mode);
 EXPORT_SYMBOL(fb_validate_mode);
 EXPORT_SYMBOL(fb_destroy_modedb);