From 0f24eb2e0e4d10cb128b4c861596d6fb53ffd5c5 Mon Sep 17 00:00:00 2001
From: Pavol Rusnak <stick@gk2.sk>
Date: Mon, 6 Jun 2016 00:58:18 +0200
Subject: [PATCH] use python implementation for backlight (for now)

---
 src/trezor/ui/__init__.py | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/trezor/ui/__init__.py b/src/trezor/ui/__init__.py
index ba86b3599..a9999f49f 100644
--- a/src/trezor/ui/__init__.py
+++ b/src/trezor/ui/__init__.py
@@ -7,6 +7,17 @@ from trezor import loop
 
 display = Display()
 
+# workaround for missing display.backlight in stmhal
+def backlight(val: int):
+    import sys
+    if sys.platform == 'trezor':
+        import pyb
+        timer = pyb.Timer(1, freq=1000)
+        val = max(0, min(100, val * 100 // 255))
+        timer.channel(1, pyb.Timer.PWM_INVERTED, pin=pyb.Pin.board.LCD_PWM, pulse_width_percent=val)
+    else:
+        display.backlight(val)
+
 
 def rgbcolor(r: int, g: int, b: int) -> int:
     return ((r & 0xF8) << 8) | ((g & 0xFC) << 3) | ((b & 0xF8) >> 3)