From 9c29529cbbd2e68d8d7414d0e9298a2131273566 Mon Sep 17 00:00:00 2001
From: Ayke van Laethem <aykevanlaethem@gmail.com>
Date: Fri, 16 Jun 2023 01:12:59 +0200
Subject: [PATCH] st7789: fix incorrect Rotation configuration
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The rotation as configured using st7789.Config was rotated 180°: 0° was
configured as 180°, 90° was configured as 270°, etc. Presumably with the
original test display, the ribbon cable was seen as the top of the
screen while if you look at product photos it is usually at the bottom.
Example:
https://www.buydisplay.com/wide-angle-1-3-inch-240x240-color-ips-tft-display-st7789-controller
Only Adafruit seems to sell these displays upside down:
https://www.adafruit.com/product/3787

This patch fixes this mistake. It should be noted that this is backwards
incompatible: all code that uses a st7789 will have to be modified to
use the correct rotation instead of the previous incorrect rotation.

If this is too big of a change, we could just keep things as-is and
pretend that all displays are upside down.
---
 st7789/st7789.go | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/st7789/st7789.go b/st7789/st7789.go
index 96b1232..5494203 100644
--- a/st7789/st7789.go
+++ b/st7789/st7789.go
@@ -474,20 +474,20 @@ func (d *Device) setRotation(rotation Rotation) error {
 	madctl := uint8(0)
 	switch rotation % 4 {
 	case drivers.Rotation0:
-		madctl = MADCTL_MX | MADCTL_MY
-		d.rowOffset = d.rowOffsetCfg
-		d.columnOffset = d.columnOffsetCfg
-	case drivers.Rotation90:
-		madctl = MADCTL_MY | MADCTL_MV
-		d.rowOffset = d.columnOffsetCfg
-		d.columnOffset = d.rowOffsetCfg
-	case drivers.Rotation180:
 		d.rowOffset = 0
 		d.columnOffset = 0
-	case drivers.Rotation270:
+	case drivers.Rotation90:
 		madctl = MADCTL_MX | MADCTL_MV
 		d.rowOffset = 0
 		d.columnOffset = 0
+	case drivers.Rotation180:
+		madctl = MADCTL_MX | MADCTL_MY
+		d.rowOffset = d.rowOffsetCfg
+		d.columnOffset = d.columnOffsetCfg
+	case drivers.Rotation270:
+		madctl = MADCTL_MY | MADCTL_MV
+		d.rowOffset = d.columnOffsetCfg
+		d.columnOffset = d.rowOffsetCfg
 	}
 	if d.isBGR {
 		madctl |= MADCTL_BGR