From 3650bc73a24fd14ff6b1310d01bf05af4c1dea75 Mon Sep 17 00:00:00 2001
From: Michael Hanselmann <public@hansmi.ch>
Date: Thu, 23 Dec 2021 21:51:44 +0100
Subject: [PATCH] waveshare213v2: Add named constants for display update flags

---
 waveshare2in13v2/controller.go     | 13 +++++++++++--
 waveshare2in13v2/waveshare213v2.go | 12 ++++++++++++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/waveshare2in13v2/controller.go b/waveshare2in13v2/controller.go
index 2af1568..ad35077 100644
--- a/waveshare2in13v2/controller.go
+++ b/waveshare2in13v2/controller.go
@@ -69,7 +69,10 @@ func configDisplayMode(ctrl controller, mode PartialUpdate, lut LUT) {
 		ctrl.sendData([]byte{0x00, 0x00, 0x00, 0x00, 0x40, 0x00, 0x00})
 
 		ctrl.sendCommand(displayUpdateControl2)
-		ctrl.sendData([]byte{0xC0})
+		ctrl.sendData([]byte{
+			displayUpdateEnableClock |
+				displayUpdateEnableAnalog,
+		})
 
 		ctrl.sendCommand(masterActivation)
 	}
@@ -89,7 +92,13 @@ func updateDisplay(ctrl controller, mode PartialUpdate) {
 	ctrl.sendData([]byte{displayUpdateFlags})
 
 	ctrl.sendCommand(displayUpdateControl2)
-	ctrl.sendData([]byte{0xC7})
+	ctrl.sendData([]byte{
+		displayUpdateDisableClock |
+			displayUpdateDisableAnalog |
+			displayUpdateDisplay |
+			displayUpdateEnableClock |
+			displayUpdateEnableAnalog,
+	})
 
 	ctrl.sendCommand(masterActivation)
 	ctrl.waitUntilIdle()
diff --git a/waveshare2in13v2/waveshare213v2.go b/waveshare2in13v2/waveshare213v2.go
index c3d68a1..b67a636 100644
--- a/waveshare2in13v2/waveshare213v2.go
+++ b/waveshare2in13v2/waveshare213v2.go
@@ -54,6 +54,18 @@ const (
 	sourceDrivingVoltageVSL_neg15V = 0x32
 )
 
+// Flags for the displayUpdateControl2 command
+const (
+	displayUpdateDisableClock byte = 1 << iota
+	displayUpdateDisableAnalog
+	displayUpdateDisplay
+	displayUpdateMode2
+	displayUpdateLoadLUTFromOTP
+	displayUpdateLoadTemperature
+	displayUpdateEnableClock
+	displayUpdateEnableAnalog
+)
+
 // Dev defines the handler which is used to access the display.
 type Dev struct {
 	c conn.Conn