From 044341875f8a0cf47952e2e1e213a4ae108532c1 Mon Sep 17 00:00:00 2001
From: NiLuJe <ninuje@gmail.com>
Date: Mon, 21 Mar 2022 03:59:24 +0100
Subject: [PATCH] Only toggle nightmode via the grayscale fb info flag on
 Kindle (#8931)

* Only toggle nightmode via the grayscale fb info flag on Kindle

Most NTX boards require elaborate trickery (see fbdepth) to actually
send a vput ioctl without the driver screwing with the rotation behind
your back.

This was causing spurious hardware rotations on exit on most Kobo
devices, something which might have gone mostly unnoticed, as current
Nickel versions will sanitize it on startup.
A simple repro was instead to start an USBMS session, as that exits
KOReader and restarts it without going through fbdepth again ;).
---
 base                               | 2 +-
 frontend/device/generic/device.lua | 1 +
 frontend/device/kindle/device.lua  | 6 ++++++
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/base b/base
index 75279018d..2a6b6d5bc 160000
--- a/base
+++ b/base
@@ -1 +1 @@
-Subproject commit 75279018d4b8eb140365eeb070da9d30de08c003
+Subproject commit 2a6b6d5bc8b4c8a2a598aca3457b7700a4ec7c35
diff --git a/frontend/device/generic/device.lua b/frontend/device/generic/device.lua
index 467b8dc55..5cf8ae660 100644
--- a/frontend/device/generic/device.lua
+++ b/frontend/device/generic/device.lua
@@ -53,6 +53,7 @@ local Device = {
     hasExternalSD = no, -- or other storage volume that cannot be accessed using the File Manager
     canHWDither = no,
     canHWInvert = no,
+    canModifyFBInfo = no, -- some NTX boards do wonky things with the rotate flag after a FBIOPUT_VSCREENINFO ioctl
     canUseCBB = yes, -- The C BB maintains a 1:1 feature parity with the Lua BB, except that is has NO support for BB4, and limited support for BBRGB24
     hasColorScreen = no,
     hasBGRFrameBuffer = no,
diff --git a/frontend/device/kindle/device.lua b/frontend/device/kindle/device.lua
index 7672c100b..2ebdce56e 100644
--- a/frontend/device/kindle/device.lua
+++ b/frontend/device/kindle/device.lua
@@ -129,6 +129,8 @@ local Kindle = Generic:new{
     hasFastWifiStatusQuery = yes,
     -- NOTE: HW inversion is generally safe on mxcfb Kindles
     canHWInvert = yes,
+    -- NOTE: And the fb driver is generally sane on those, too
+    canModifyFBInfo = yes,
     -- NOTE: Newer devices will turn the frontlight off at 0
     canTurnFrontlightOff = yes,
     home_dir = "/mnt/us",
@@ -326,6 +328,7 @@ local Kindle2 = Kindle:new{
     hasKeys = yes,
     hasDPad = yes,
     canHWInvert = no,
+    canModifyFBInfo = no,
     canUseCBB = no, -- 4bpp
     canUseWAL = no, -- Kernel too old to support mmap'ed I/O on /mnt/us
     supportsScreensaver = yes, -- The first ad-supported device was the K3
@@ -338,6 +341,7 @@ local KindleDXG = Kindle:new{
     hasKeys = yes,
     hasDPad = yes,
     canHWInvert = no,
+    canModifyFBInfo = no,
     canUseCBB = no, -- 4bpp
     canUseWAL = no, -- Kernel too old to support mmap'ed I/O on /mnt/us
     supportsScreensaver = yes, -- The first ad-supported device was the K3
@@ -350,6 +354,7 @@ local Kindle3 = Kindle:new{
     hasKeys = yes,
     hasDPad = yes,
     canHWInvert = no,
+    canModifyFBInfo = no,
     canUseCBB = no, -- 4bpp
     isSpecialOffers = hasSpecialOffers(),
 }
@@ -360,6 +365,7 @@ local Kindle4 = Kindle:new{
     hasKeys = yes,
     hasDPad = yes,
     canHWInvert = no,
+    canModifyFBInfo = no,
     -- NOTE: It could *technically* use the C BB, as it's running @ 8bpp, but it's expecting an inverted palette...
     canUseCBB = no,
     isSpecialOffers = hasSpecialOffers(),