From 0b5033f798e6179775a02eb50bba837b7f6fa2e8 Mon Sep 17 00:00:00 2001
From: Cameron Fleming <cameron@nevexo.space>
Date: Thu, 13 Feb 2025 13:42:07 +0000
Subject: [PATCH] feat: restore EDID on reboot (#34)

This commit adds the config entry "EdidString" and saves the EDID string
when it's modified via the RPC.

The EDID is restored when the jetkvm_native control socket connects
(usually at boot)

Signed-off-by: Cameron Fleming <cameron@nevexo.space>
---
 config.go  |  1 +
 jsonrpc.go |  6 ++++++
 native.go  | 16 ++++++++++++++++
 3 files changed, 23 insertions(+)

diff --git a/config.go b/config.go
index 1636434..ceacfe5 100644
--- a/config.go
+++ b/config.go
@@ -22,6 +22,7 @@ type Config struct {
 	LocalAuthToken    string            `json:"local_auth_token"`
 	LocalAuthMode     string            `json:"localAuthMode"` //TODO: fix it with migration
 	WakeOnLanDevices  []WakeOnLanDevice `json:"wake_on_lan_devices"`
+	EdidString        string            `json:"hdmi_edid_string"`
 }
 
 const configPath = "/userdata/kvm_config.json"
diff --git a/jsonrpc.go b/jsonrpc.go
index 2ce5f18..4f6519b 100644
--- a/jsonrpc.go
+++ b/jsonrpc.go
@@ -183,6 +183,12 @@ func rpcSetEDID(edid string) error {
 	if err != nil {
 		return err
 	}
+
+	// Save EDID to config, allowing it to be restored on reboot.
+	LoadConfig()
+	config.EdidString = edid
+	SaveConfig()
+
 	return nil
 }
 
diff --git a/native.go b/native.go
index d34ab07..1bd8429 100644
--- a/native.go
+++ b/native.go
@@ -152,6 +152,9 @@ func handleCtrlClient(conn net.Conn) {
 
 	ctrlSocketConn = conn
 
+	// Restore HDMI EDID if applicable
+	go restoreHdmiEdid()
+
 	readBuf := make([]byte, 4096)
 	for {
 		n, err := conn.Read(readBuf)
@@ -304,3 +307,16 @@ func ensureBinaryUpdated(destPath string) error {
 
 	return nil
 }
+
+// Restore the HDMI EDID value from the config.
+// Called after successful connection to jetkvm_native.
+func restoreHdmiEdid() {
+	LoadConfig()
+	if config.EdidString != "" {
+		logger.Infof("Restoring HDMI EDID to %v", config.EdidString)
+		_, err := CallCtrlAction("set_edid", map[string]interface{}{"edid": config.EdidString})
+		if err != nil {
+			logger.Errorf("Failed to restore HDMI EDID: %v", err)
+		}
+	}
+}