1 files changed, 85 insertions, 0 deletions
diff --git a/drivers/video/fbdev/via/via_aux_edid.c b/drivers/video/fbdev/via/via_aux_edid.c
new file mode 100644
index 000000000..9791381a9
--- /dev/null
+++ b/drivers/video/fbdev/via/via_aux_edid.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2011 Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
+ */
+/*
+ * generic EDID driver
+ */
+
+#include <linux/slab.h>
+#include <linux/fb.h>
+#include "via_aux.h"
+#include "../edid.h"
+
+
+static const char *name = "EDID";
+
+
+static void query_edid(struct via_aux_drv *drv)
+{
+	struct fb_monspecs *spec = drv->data;
+	unsigned char edid[EDID_LENGTH];
+	bool valid = false;
+
+	if (spec) {
+		fb_destroy_modedb(spec->modedb);
+	} else {
+		spec = kmalloc(sizeof(*spec), GFP_KERNEL);
+		if (!spec)
+			return;
+	}
+
+	spec->version = spec->revision = 0;
+	if (via_aux_read(drv, 0x00, edid, EDID_LENGTH)) {
+		fb_edid_to_monspecs(edid, spec);
+		valid = spec->version || spec->revision;
+	}
+
+	if (!valid) {
+		kfree(spec);
+		spec = NULL;
+	} else
+		printk(KERN_DEBUG "EDID: %s %s\n", spec->manufacturer, spec->monitor);
+
+	drv->data = spec;
+}
+
+static const struct fb_videomode *get_preferred_mode(struct via_aux_drv *drv)
+{
+	struct fb_monspecs *spec = drv->data;
+	int i;
+
+	if (!spec || !spec->modedb || !(spec->misc & FB_MISC_1ST_DETAIL))
+		return NULL;
+
+	for (i = 0; i < spec->modedb_len; i++) {
+		if (spec->modedb[i].flag & FB_MODE_IS_FIRST &&
+			spec->modedb[i].flag & FB_MODE_IS_DETAILED)
+			return &spec->modedb[i];
+	}
+
+	return NULL;
+}
+
+static void cleanup(struct via_aux_drv *drv)
+{
+	struct fb_monspecs *spec = drv->data;
+
+	if (spec)
+		fb_destroy_modedb(spec->modedb);
+}
+
+void via_aux_edid_probe(struct via_aux_bus *bus)
+{
+	struct via_aux_drv drv = {
+		.bus	=	bus,
+		.addr	=	0x50,
+		.name	=	name,
+		.cleanup	=	cleanup,
+		.get_preferred_mode	=	get_preferred_mode};
+
+	query_edid(&drv);
+
+	/* as EDID devices can be connected/disconnected just add the driver */
+	via_aux_add(&drv);
+}