implement support for display brightness

commit 54e685ba9fef2b5fc1505ddc932e4fa3fe87ed68
Author: itsmattkc <34096995+itsmattkc@users.noreply.github.com>
Date:   Wed Aug 26 17:46:15 2026 -0700

    improvements

commit b442a51a71
Author: itsmattkc <34096995+itsmattkc@users.noreply.github.com>
Date:   Wed Aug 26 14:49:31 2026 -0700

    docker: add new build deps for android

commit 1e6370391e
Merge: b21181c 0681459
Author: itsmattkc <34096995+itsmattkc@users.noreply.github.com>
Date:   Wed Aug 26 14:37:15 2026 -0700

    Merge branch 'master' into brightness

commit b21181c675
Author: itsmattkc <34096995+itsmattkc@users.noreply.github.com>
Date:   Sun Aug 23 16:58:09 2026 -0700

    update display brightness - initial implementation

android/app/src/main/java/com/mattkc/vanilla/VanillaActivity.java

@@ -2,6 +2,7 @@ package com.mattkc.vanilla;
 
 import android.graphics.SurfaceTexture;
 import android.view.Surface;
+import android.view.WindowManager;
 
 import java.util.concurrent.atomic.AtomicBoolean;
 
@@ -56,4 +57,18 @@ public class VanillaActivity extends SDLActivity {
 			videoSurfaceTexture = null;
 		}
 	}
+
+	public static boolean setScreenBrightness(float brightness) {
+		final VanillaActivity activity = (VanillaActivity) mSingleton;
+		if (activity == null) {
+			return false;
+		}
+
+		activity.runOnUiThread(() -> {
+			WindowManager.LayoutParams attributes = activity.getWindow().getAttributes();
+			attributes.screenBrightness = Math.max(0.0f, Math.min(1.0f, brightness));
+			activity.getWindow().setAttributes(attributes);
+		});
+		return true;
+	}
 }

buildroot/board/nx/rootfs/usr/bin/vanilla-nx-power-btn

@@ -1,15 +0,0 @@
-#!/bin/sh
-
-# Listen for power button presses, in which case quit Vanilla (which should in turn reboot the Switch)
-
-DEV=/dev/input/event0
-APP=vanilla
-
-evtest "$DEV" 2>/dev/null | while read -r line; do
-    case "$line" in
-        *KEY_SLEEP*,\ value\ 1*)
-            pid="$(pidof "$APP" | awk '{print $1}')"
-            [ -n "$pid" ] && kill -TERM "$pid"
-            ;;
-    esac
-done

buildroot/board/nx/rootfs/usr/bin/vanilla-nx-volume-btn

@@ -1,16 +0,0 @@
-#!/bin/sh
-
-# Listen for volume button presses, in which case increase/decrease volume in ALSA
-
-DEV=/dev/input/event5
-
-evtest "$DEV" 2>/dev/null | while read -r line; do
-    case "$line" in
-        *KEY_VOLUMEDOWN*,\ value\ 1*)
-            amixer sset 'x Speaker' 5%- >/dev/null
-            ;;
-        *KEY_VOLUMEUP*,\ value\ 1*)
-            amixer sset 'x Speaker' 5%+ unmute >/dev/null
-            ;;
-    esac
-done

buildroot/board/nx/rootfs/usr/bin/vanilla-wrapper

@@ -5,19 +5,6 @@ export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:/usr/lib/aarch64-linux-gnu/tegra:/usr/l
 export DISPLAY=:0
 export SDL_VIDEODRIVER=x11
 
-# Listen for power button presses
-/usr/bin/vanilla-nx-power-btn &
-POWER_BTN_WATCHER_PID=$!
-/usr/bin/vanilla-nx-volume-btn &
-VOLUME_BTN_WATCHER_PID=$!
-
-# Ensure watcher is closed
-cleanup() {
-    kill "$POWER_BTN_WATCHER_PID" 2>/dev/null
-    kill "$VOLUME_BTN_WATCHER_PID" 2>/dev/null
-}
-trap cleanup EXIT
-
 # Start X
 X "$DISPLAY" -nolisten tcp vt1 &
 X_PID=$!

buildroot/configs/vanilla_nintendoswitch_defconfig

@@ -7,7 +7,7 @@ BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_EUDEV=y
 BR2_TARGET_GENERIC_ROOT_PASSWD="root"
 # BR2_TARGET_GENERIC_GETTY is not set
 # BR2_TARGET_GENERIC_REMOUNT_ROOTFS_RW is not set
-BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/board/nx/rootfs/"
+BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/board/nx/rootfs/ $(BR2_EXTERNAL_VANILLA_PATH)/rootfs/"
 BR2_ROOTFS_POST_BUILD_SCRIPT="$(BR2_EXTERNAL_VANILLA_PATH)/board/nx/post_build.sh"
 BR2_LINUX_KERNEL=y
 BR2_LINUX_KERNEL_IMAGEGZ=y

buildroot/configs/vanilla_orangepi_zero2w_defconfig

@@ -7,7 +7,7 @@ BR2_GLOBAL_PATCH_DIR="board/orangepi/orangepi-zero2w/patches  $(BR2_EXTERNAL_VAN
 BR2_TARGET_GENERIC_ISSUE="Welcome to Orangepi Zero2W"
 BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_EUDEV=y
 # BR2_TARGET_GENERIC_GETTY is not set
-BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/board/orangepizero3/rootfs/"
+BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/board/orangepizero3/rootfs/ $(BR2_EXTERNAL_VANILLA_PATH)/rootfs/"
 BR2_ROOTFS_POST_BUILD_SCRIPT="board/orangepi/common/post-build.sh $(BR2_EXTERNAL_VANILLA_PATH)/board/orangepizero3/post_build.sh"
 BR2_ROOTFS_POST_IMAGE_SCRIPT="support/scripts/genimage.sh"
 BR2_ROOTFS_POST_SCRIPT_ARGS="-c $(BINARIES_DIR)/genimage.cfg"

buildroot/configs/vanilla_orangepi_zero3_defconfig

@@ -8,7 +8,7 @@ BR2_TARGET_GENERIC_ISSUE="Welcome to Orangepi Zero3"
 BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_EUDEV=y
 # BR2_TARGET_GENERIC_GETTY is not set
 BR2_SYSTEM_DHCP="eth0"
-BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/board/orangepizero3/rootfs/"
+BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/board/orangepizero3/rootfs/  $(BR2_EXTERNAL_VANILLA_PATH)/rootfs/"
 BR2_ROOTFS_POST_BUILD_SCRIPT="board/orangepi/common/post-build.sh $(BR2_EXTERNAL_VANILLA_PATH)/board/orangepizero3/post_build.sh"
 BR2_ROOTFS_POST_IMAGE_SCRIPT="support/scripts/genimage.sh"
 BR2_ROOTFS_POST_SCRIPT_ARGS="-c $(BINARIES_DIR)/genimage.cfg"

buildroot/configs/vanilla_raspberrypi0w_defconfig

@@ -5,7 +5,7 @@ BR2_GLOBAL_PATCH_DIR="board/raspberrypi/patches"
 BR2_DOWNLOAD_FORCE_CHECK_HASHES=y
 BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_EUDEV=y
 # BR2_TARGET_GENERIC_GETTY is not set
-#BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/board/raspberrypi/rootfs"
+BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/rootfs/"
 BR2_ROOTFS_POST_BUILD_SCRIPT="board/raspberrypi0w/post-build.sh $(BR2_EXTERNAL_VANILLA_PATH)/board/raspberrypi/post_build.sh"
 BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi0w/post-image.sh"
 BR2_LINUX_KERNEL=y

buildroot/configs/vanilla_raspberrypi_64_defconfig

@@ -6,7 +6,7 @@ BR2_GLOBAL_PATCH_DIR="board/raspberrypi/patches"
 BR2_DOWNLOAD_FORCE_CHECK_HASHES=y
 BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_EUDEV=y
 # BR2_TARGET_GENERIC_GETTY is not set
-#BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/board/raspberrypi/rootfs"
+BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_VANILLA_PATH)/rootfs/"
 BR2_ROOTFS_POST_BUILD_SCRIPT="board/raspberrypi/post-build.sh $(BR2_EXTERNAL_VANILLA_PATH)/board/raspberrypi/post_build.sh"
 BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi/post-image.sh"
 BR2_LINUX_KERNEL=y

buildroot/rootfs/usr/libexec/vanilla-volume

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+case "$1" in
+    up)
+        exec amixer -q sset 'x Speaker' 5%+ unmute
+        ;;
+    down)
+        exec amixer -q sset 'x Speaker' 5%-
+        ;;
+    *)
+        exit 2
+        ;;
+esac

docker/android/Dockerfile

@@ -2,7 +2,7 @@ FROM docker.io/ubuntu:24.04@sha256:33ceb71981b602c1a7443a53469e4dba065f7503eab30
 
 # Install build dependencies
 RUN apt update && \
-    apt -y install wget unzip git openjdk-17-jdk make && \
+    apt -y install wget unzip git openjdk-17-jdk make autoconf automake libtool pkg-config && \
     apt-get clean && \
     apt-get autoremove --yes && \
     rm -rf /var/lib/{apt,dpkg,cache,log}/

gui/CMakeLists.txt

@@ -309,6 +309,10 @@ if (ANDROID)
 endif()
 
 if (LINUX)
+    list(APPEND VANILLA_GUI_SRC
+        ui/ui_sdl_linux.c
+    )
+
     # Link with DRM if available
     option(VANILLA_BUILD_USE_DRM "Enable DRM video output" ON)
     if (VANILLA_BUILD_USE_DRM)

gui/config.c

@@ -93,6 +93,9 @@ void vpi_config_save()
     sprintf(buf, "%i", vpi_config.force_software_decode);
     xmlTextWriterWriteElement(writer, BAD_CAST "swdec", BAD_CAST buf);
 
+    sprintf(buf, "%f", vpi_config.screen_brightness);
+    xmlTextWriterWriteElement(writer, BAD_CAST "brightness", BAD_CAST buf);
+
     xmlTextWriterStartElement(writer, BAD_CAST "controls");
     if (vpi_config.keymap) {
         xmlTextWriterStartElement(writer, BAD_CAST "keys");
@@ -184,6 +187,7 @@ void vpi_config_init()
     vpi_config_reset_default_controls_internal();
     vpi_config.cursor_in_fullscreen = 0;
     vpi_config.autoconnect = -1;
+    vpi_config.screen_brightness = 0.5f;
 
     // Load from file
     char config_fn[1024];
@@ -250,6 +254,8 @@ void vpi_config_init()
                         vpi_config.fullscreen = atoi((const char *) child->children->content);
                     } else if (!strcmp((const char *) child->name, "swdec")) {
                         vpi_config.force_software_decode = atoi((const char *) child->children->content);
+                    } else if (!strcmp((const char *) child->name, "brightness")) {
+                        vpi_config.screen_brightness = atof((const char *) child->children->content);
                     } else if (!strcmp((const char *) child->name, "controls")) {
                         xmlNodePtr section = child->children;
                         while(section){

gui/config.h

@@ -33,6 +33,7 @@ typedef struct {
     int fast_drm;
     int force_software_decode;
     int autoconnect;
+    float screen_brightness;
 } vpi_config_t;
 
 extern vpi_config_t vpi_config;

gui/main.c

@@ -97,6 +97,14 @@ int SDL_main(int argc, const char **argv)
         goto exit;
     }
 
+#ifndef ANDROID
+    // On Linux/Buildroot platforms like Raspberry Pi and Nintendo Switch, it
+    // is desirable for the brightness to be restored from config. On Android
+    // though, the brightness will be set externally so changing it here is
+    // probably not desirable.
+    vui_brightness_set(vui, vpi_config.screen_brightness);
+#endif
+
     vpi_menu_init(vui);
 
     while (vui_update_sdl(vui)) {

gui/menu/menu.c

@@ -13,6 +13,20 @@
 #include "menu_main.h"
 #include "platform.h"
 
+#if defined(__linux__) && !defined(ANDROID) && !defined(__ANDROID__)
+#include <pthread.h>
+#include <string.h>
+
+// Calling system() is synchronous and causes a noticeable pause during
+// gameplay. This allows us to thunk from a separate detached thread so it
+// doesn't interrupt the main thread.
+static void *run_volume_helper(void *command)
+{
+    (void) system((const char *) command);
+    return NULL;
+}
+#endif
+
 void vpi_mic_callback(void *userdata, const uint8_t *data, size_t len)
 {
 	vanilla_send_audio(data, len);
@@ -80,6 +94,31 @@ void vpi_menu_action(vui_context_t *vui, vpi_extra_action_t action)
         vpi_config.fullscreen = !vpi_config.fullscreen;
         vpi_config_save();
         vui_set_fullscreen(vui, vpi_config.fullscreen);
+        break;
+    }
+    case VPI_ACTION_VOLUME_UP:
+    case VPI_ACTION_VOLUME_DOWN:
+    {
+#if defined(__linux__) && !defined(ANDROID) && !defined(__ANDROID__)
+        // On some platforms (specifically our Buildroot platforms like the
+        // Raspberry Pi and Nintendo Switch), there's no built-in handler for
+        // the volume keys. So here we handle them ourselves.
+        const char *helper = "/usr/libexec/vanilla-volume";
+        if (access(helper, X_OK) == 0) {
+            const char *command = action == VPI_ACTION_VOLUME_UP
+                ? "/usr/libexec/vanilla-volume up"
+                : "/usr/libexec/vanilla-volume down";
+            pthread_t thread;
+            int error = pthread_create(&thread, NULL, run_volume_helper, (void *) command);
+            if (error == 0) {
+                error = pthread_detach(thread);
+            }
+            if (error != 0) {
+                vpilog("Failed to start volume helper thread: %s\n", strerror(error));
+            }
+        }
+#endif
+        break;
     }
     }
 }

gui/menu/menu.h

@@ -9,6 +9,8 @@ typedef enum {
     VPI_ACTION_TOGGLE_RECORDING,
     VPI_ACTION_DISCONNECT,
     VPI_ACTION_TOGGLE_FULLSCREEN,
+    VPI_ACTION_VOLUME_UP,
+    VPI_ACTION_VOLUME_DOWN
 } vpi_extra_action_t;
 
 void vpi_menu_init(vui_context_t *vui);

gui/menu/menu_game.c

@@ -1088,6 +1088,21 @@ void *vpi_event_loop(void *arg)
 		case VANILLA_EVENT_MIC:
 			vui_mic_enabled_set(vui, event.data[0]);
 			break;
+        case VANILLA_EVENT_BRIGHTNESS:
+        {
+            // Clamp to valid values from console
+            uint8_t value = CLAMP(event.data[0], 1, 5);
+
+            // Normalize to 0.0 - 1.0
+            // float b = value / 5.0f;
+            float b = (value - 1) / 4.0f;
+            if (b < 0.01f) b = 0.01f;
+
+            vpi_config.screen_brightness = b;
+            vpi_config_save();
+            vui_brightness_set(vui, b);
+            break;
+        }
         }
 
 		vanilla_free_event(&event);

gui/ui/ui.c

@@ -1041,3 +1041,10 @@ void vui_mic_callback_set(vui_context_t *ctx, vui_mic_callback_t callback, void
 	ctx->mic_callback = callback;
 	ctx->mic_callback_data = userdata;
 }
+
+void vui_brightness_set(vui_context_t *ctx, float brightness)
+{
+    if (ctx->brightness_set_handler) {
+        ctx->brightness_set_handler(ctx, brightness, ctx->brightness_set_handler_data);
+    }
+}

gui/ui/ui.h

@@ -182,4 +182,9 @@ vui_power_state_t vui_power_state_get(vui_context_t *ctx, int *percent);
 void vui_mic_enabled_set(vui_context_t *ctx, int enabled);
 void vui_mic_callback_set(vui_context_t *ctx, vui_mic_callback_t callback, void *userdata);
 
+/**
+ * Miscellaneous functions
+ */
+void vui_brightness_set(vui_context_t *ctx, float brightness); // Expects brightness between 0.0f and 1.0f
+
 #endif // VANILLA_PI_UI_H

gui/ui/ui_priv.h

@@ -104,6 +104,7 @@ typedef int (*vui_font_height_handler_t)(vui_font_size_t size, void *userdata);
 typedef void (*vui_text_open_handler_t)(vui_context_t *ctx, int textedit, int open, void *userdata);
 typedef vui_power_state_t (*vui_power_state_handler_t)(vui_context_t *ctx, int *percent);
 typedef void (*vui_audio_enabled_handler_t)(vui_context_t *ctx, int enabled, void *userdata);
+typedef void (*vui_brightness_set_handler_t)(vui_context_t *ctx, float value, void *userdata);
 
 typedef struct vui_context_t {
     void *platform_data;
@@ -155,6 +156,8 @@ typedef struct vui_context_t {
 	void *audio_enabled_handler_data;
 	vui_bool_callback_t fullscreen_enabled_handler;
 	void *fullscreen_enabled_handler_data;
+    vui_brightness_set_handler_t brightness_set_handler;
+    void *brightness_set_handler_data;
 
     int default_button_map[VPI_CONFIG_BUTTONMAP_SIZE];
     int default_axis_map[VPI_CONFIG_AXISMAP_SIZE];

gui/ui/ui_sdl.c

@@ -49,6 +49,12 @@
 #include "platform_nx_imu.h"
 #endif
 
+#if defined(ANDROID) || defined(__ANDROID__)
+// TODO
+#elif defined(__linux__)
+#include "ui_sdl_linux.h"
+#endif
+
 #define MIN(a,b) (((a)<(b))?(a):(b))
 #define PW_CHAR_SIZE 20
 #define PW_CHAR_PAD 2
@@ -187,6 +193,10 @@ void init_gamepad(vui_context_t *ctx)
     ctx->default_key_map[SDL_SCANCODE_F12] = VPI_ACTION_SCREENSHOT;
     ctx->default_key_map[SDL_SCANCODE_F11] = VPI_ACTION_TOGGLE_FULLSCREEN;
     ctx->default_key_map[SDL_SCANCODE_ESCAPE] = VPI_ACTION_DISCONNECT;
+
+    ctx->default_key_map[SDL_SCANCODE_SLEEP] = VPI_ACTION_DISCONNECT; // Nintendo Switch power button
+    ctx->default_key_map[SDL_SCANCODE_VOLUMEUP] = VPI_ACTION_VOLUME_UP;
+    ctx->default_key_map[SDL_SCANCODE_VOLUMEDOWN] = VPI_ACTION_VOLUME_DOWN;
 }
 
 void find_valid_controller(vui_sdl_context_t *sdl_ctx)
@@ -354,6 +364,26 @@ void vui_sdl_fullscreen_enabled_handler(vui_context_t *ctx, int enabled, void *u
     SDL_ShowCursor(vpi_config.cursor_in_fullscreen || !enabled);
 }
 
+void vui_sdl_brightness_set_handler(vui_context_t *ctx, float brightness, void *userdata)
+{
+    vui_sdl_context_t *sdl_ctx = (vui_sdl_context_t *) ctx->platform_data;
+
+    vpilog("SETTING BRIGHTNESS TO %.1f\n", brightness);
+
+#if defined(ANDROID) || defined(__ANDROID__)
+    if (vui_sdl_android_set_brightness(brightness) == 0) {
+        return;
+    }
+#elif defined(__linux__)
+    if (vui_sdl_linux_set_brightness(brightness) == 0) {
+        return;
+    }
+#endif
+
+    // Fallback
+    SDL_SetWindowBrightness(sdl_ctx->window, brightness);
+}
+
 void vui_sdl_get_key_mapping_handler(vui_context_t *ctx, int vanilla_btn, void *userdata)
 {
 
@@ -537,7 +567,7 @@ int vui_sdl_event_thread(void *data)
                 break;
             case SDL_CONTROLLERBUTTONDOWN:
             case SDL_CONTROLLERBUTTONUP:
-                if (sdl_ctx->controller && ev.cdevice.which == SDL_JoystickInstanceID(SDL_GameControllerGetJoystick(sdl_ctx->controller))) {
+            if (sdl_ctx->controller && ev.cdevice.which == SDL_JoystickInstanceID(SDL_GameControllerGetJoystick(sdl_ctx->controller))) {
                     int btn_idx = ev.cbutton.button;
                     int vanilla_btn;
 
@@ -880,6 +910,8 @@ int vui_init_sdl(vui_context_t *ctx, int fullscreen)
 
     ctx->fullscreen_enabled_handler = vui_sdl_fullscreen_enabled_handler;
 
+    ctx->brightness_set_handler = vui_sdl_brightness_set_handler;
+
     if (TTF_Init()) {
         vpilog("Failed to TTF_Init\n");
         return -1;

gui/ui/ui_sdl_android.c

@@ -12,6 +12,7 @@ static jobject video_surface;
 static jmethodID create_surface_method;
 static jmethodID update_texture_method;
 static jmethodID destroy_surface_method;
+static jmethodID set_brightness_method;
 
 static int handle_jni_exception(JNIEnv *env, const char *operation)
 {
@@ -53,7 +54,8 @@ static int init_jni(JNIEnv *env)
     create_surface_method = (*env)->GetStaticMethodID(env, video_class, "createVideoSurface", "(III)Landroid/view/Surface;");
     update_texture_method = (*env)->GetStaticMethodID(env, video_class, "updateVideoSurfaceTexture", "()[F");
     destroy_surface_method = (*env)->GetStaticMethodID(env, video_class, "destroyVideoSurface", "()V");
-    if (!create_surface_method || !update_texture_method || !destroy_surface_method ||
+    set_brightness_method = (*env)->GetStaticMethodID(env, video_class, "setScreenBrightness", "(F)Z");
+    if (!create_surface_method || !update_texture_method || !destroy_surface_method || !set_brightness_method ||
         handle_jni_exception(env, "looking up video surface methods") < 0) {
         (*env)->DeleteGlobalRef(env, video_class);
         video_class = NULL;
@@ -69,6 +71,7 @@ static int init_jni(JNIEnv *env)
         create_surface_method = NULL;
         update_texture_method = NULL;
         destroy_surface_method = NULL;
+        set_brightness_method = NULL;
         return -1;
     }
 
@@ -144,6 +147,21 @@ void *vui_sdl_android_get_video_surface(void)
     return video_surface;
 }
 
+int vui_sdl_android_set_brightness(float brightness)
+{
+    JNIEnv *env = (JNIEnv *) SDL_AndroidGetJNIEnv();
+    if (!env || init_jni(env) < 0) {
+        return -1;
+    }
+
+    jboolean dispatched = (*env)->CallStaticBooleanMethod(env, video_class, set_brightness_method,
+                                                          (jfloat) brightness);
+    if (handle_jni_exception(env, "setting screen brightness") < 0) {
+        return -1;
+    }
+    return dispatched ? 0 : -1;
+}
+
 int vui_sdl_android_update_video_texture(float transform[16])
 {
     JNIEnv *env = (JNIEnv *) SDL_AndroidGetJNIEnv();
@@ -192,4 +210,5 @@ void vui_sdl_android_destroy_video_texture(void)
     create_surface_method = NULL;
     update_texture_method = NULL;
     destroy_surface_method = NULL;
+    set_brightness_method = NULL;
 }

gui/ui/ui_sdl_android.h

@@ -8,5 +8,6 @@ int vui_sdl_android_create_video_texture(SDL_Renderer *renderer, int width,
 void *vui_sdl_android_get_video_surface(void);
 int vui_sdl_android_update_video_texture(float transform[16]);
 void vui_sdl_android_destroy_video_texture(void);
+int vui_sdl_android_set_brightness(float brightness);
 
 #endif

gui/ui/ui_sdl_linux.c

@@ -0,0 +1,103 @@
+#include "ui_sdl_linux.h"
+
+#include <dirent.h>
+#include <errno.h>
+#include <math.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "ui_util.h"
+
+#define VUI_LINUX_BACKLIGHT_ROOT "/sys/class/backlight"
+#define VUI_LINUX_BACKLIGHT_DEFAULT "backlight"
+#define VUI_LINUX_BACKLIGHT_PATH_SIZE 4096
+
+static int vui_sdl_linux_set_backlight_device(const char *device, float brightness)
+{
+    char path[VUI_LINUX_BACKLIGHT_PATH_SIZE];
+    unsigned int max_brightness;
+    unsigned int value;
+    int path_length;
+    int write_failed;
+    int close_failed;
+    FILE *file;
+
+    if (!isfinite(brightness)) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    brightness = CLAMP(brightness, 0.0f, 1.0f);
+
+    // Attempt to read max_brightness information
+    path_length = snprintf(path, sizeof(path), "%s/%s/max_brightness", VUI_LINUX_BACKLIGHT_ROOT, device);
+    if (path_length < 0 || path_length >= (int) sizeof(path)) {
+        errno = ENAMETOOLONG;
+        return -1;
+    }
+
+    file = fopen(path, "r");
+    if (!file) {
+        return -1;
+    }
+
+    if (fscanf(file, "%u", &max_brightness) != 1 || !max_brightness) {
+        fclose(file);
+        errno = EINVAL;
+        return -1;
+    }
+    fclose(file);
+
+    // Now that we have max_brightness, attempt to set actual brightness to a percentage of max brightness
+    value = lroundf(brightness * max_brightness);
+
+    path_length = snprintf(path, sizeof(path), "%s/%s/brightness", VUI_LINUX_BACKLIGHT_ROOT, device);
+    if (path_length < 0 || path_length >= (int) sizeof(path)) {
+        errno = ENAMETOOLONG;
+        return -1;
+    }
+
+    file = fopen(path, "w");
+    if (!file) {
+        return -1;
+    }
+
+    write_failed = fprintf(file, "%u\n", value) < 0;
+    close_failed = fclose(file) != 0;
+    if (write_failed || close_failed) {
+        return -1;
+    }
+
+    return 0;
+}
+
+int vui_sdl_linux_set_brightness(float brightness)
+{
+    DIR *directory;
+    struct dirent *entry;
+
+    // See if "backlight" device exists (should exist on Nintendo Switch)
+    if (access(VUI_LINUX_BACKLIGHT_ROOT "/" VUI_LINUX_BACKLIGHT_DEFAULT, F_OK) == 0) {
+        return vui_sdl_linux_set_backlight_device(VUI_LINUX_BACKLIGHT_DEFAULT, brightness);
+    }
+
+    // Otherwise, iterate over directory to find next best device to set brightness on
+    directory = opendir(VUI_LINUX_BACKLIGHT_ROOT);
+    if (!directory) {
+        return -1;
+    }
+
+    while ((entry = readdir(directory))) {
+        if (entry->d_name[0] == '.') {
+            continue;
+        }
+
+        if (vui_sdl_linux_set_backlight_device(entry->d_name, brightness) == 0) {
+            closedir(directory);
+            return 0;
+        }
+    }
+
+    closedir(directory);
+    return -1;
+}

gui/ui/ui_sdl_linux.h

@@ -0,0 +1,6 @@
+#ifndef VANILLA_PI_UI_SDL_LINUX_H
+#define VANILLA_PI_UI_SDL_LINUX_H
+
+int vui_sdl_linux_set_brightness(float brightness);
+
+#endif // VANILLA_PI_UI_SDL_LINUX_H

gui/ui/ui_util.h

@@ -9,6 +9,8 @@ void vui_strncpy(char *dst, const char *src, size_t max_dst_size);
 size_t vui_utf8_cp_len(const char *s);
 char *vui_utf8_advance(char *s);
 
+#define CLAMP(x, low, high) (((x) < (low)) ? (low) : ((x) > (high)) ? (high) : (x))
+
 static inline int intmin(int a, int b) { return a < b ? a : b; }
 static inline int intmax(int a, int b) { return a > b ? a : b; }
 static inline int64_t int64min(int64_t a, int64_t b) { return a < b ? a : b; }

lib/gamepad/command.c

@@ -60,7 +60,7 @@ void send_generic_response(int skt, CmdHeader *response)
 void handle_generic_packet(gamepad_context_t *info, int skt, GenericPacket *request)
 {
     GenericCmdHeader *gen_cmd = &request->generic_cmd_header;
-    vanilla_log("magic: %x, flags: %x, service ID: %u, method ID: %u", gen_cmd->magic_0x7E, gen_cmd->flags, gen_cmd->service_id, gen_cmd->method_id);
+    // vanilla_log("magic: %x, flags: %x, service ID: %u, method ID: %u", gen_cmd->magic_0x7E, gen_cmd->flags, gen_cmd->service_id, gen_cmd->method_id);
 
     // Prepare response
     GenericPacket response;
@@ -170,13 +170,39 @@ void handle_generic_packet(gamepad_context_t *info, int skt, GenericPacket *requ
         }
         case METHOD_ID_PERIPHERAL_UPDATE_EEPROM:
         {
-            vanilla_log("5,12 - index: %u, length: %u", response.payload[0], response.payload[1]);
+            uint8_t index = request->payload[0];
-            response.generic_cmd_header.error_code = 0;
+            uint8_t length = request->payload[1];
+
+            vanilla_log("5,12 - index: %u, length: %u", index, length);
+
+            uint16_t our_crc = crc16(request->payload + 2, length - 2);
+            uint16_t their_crc = le16toh(*(uint16_t *)(request->payload + 2 + length - 2));
+
+            if (our_crc != their_crc) {
+                // TODO: Report some kind of error to the console?
+            } else {
+                // Update our EEPROM
+                switch (index) {
+                case 0x10:
+                {
+                    // Console wants to change our brightness
+                    // vanilla_log("Change brightness to %x", request->payload[2]);
+                    uint8_t b = request->payload[2];
+                    push_event(info->event_loop, VANILLA_EVENT_BRIGHTNESS, &b, sizeof(b));
+                    break;
+                }
+                default:
+                    vanilla_log("Console attempted write to unknown EEPROM offset: 0x%x", index);
+                }
+
+                // Report success
+                response.generic_cmd_header.error_code = 0;
+            }
             break;
         }
         case METHOD_ID_PERIPHERAL_SET_REMOCON:
         {
-            vanilla_log("5,24 - str1: %s, str2: %s", response.payload, response.payload + 5);
+            vanilla_log("5,24 - str1: %s, str2: %s", request->payload, request->payload + 5);
             response.generic_cmd_header.error_code = 0;
             break;
         }
@@ -227,7 +253,7 @@ void handle_time_packet(int skt, TimePacket *request)
 
 void handle_command_packet(gamepad_context_t *info, int skt, CmdHeader *request)
 {
-	vanilla_log("packet_type: %u, query_type: %u, payload_size: 0x%X", request->packet_type, request->query_type, request->payload_size);
+	// vanilla_log("packet_type: %u, query_type: %u, payload_size: 0x%X", request->packet_type, request->query_type, request->payload_size);
     switch (request->packet_type)
     {
     case PACKET_TYPE_REQUEST:

lib/gamepad/video.c

@@ -20,15 +20,6 @@
 #include "vanilla.h"
 #include "util.h"
 
-#if defined(_WIN32)
-// Windows has no htobe32, and is always virtually little-endiam
-#define htobe32(x) htonl(x)
-#elif defined(__APPLE__)
-// macOS has no htobe32
-#include <libkern/OSByteOrder.h>
-#define htobe32(x) OSSwapHostToBigInt32(x)
-#endif // __APPLE__
-
 typedef struct
 {
     unsigned magic : 4;

lib/vanilla.h

@@ -74,7 +74,8 @@ enum VanillaEvent
     VANILLA_EVENT_VIBRATE,
     VANILLA_EVENT_SYNC,
     VANILLA_EVENT_ERROR,
-	VANILLA_EVENT_MIC
+	VANILLA_EVENT_MIC,
+    VANILLA_EVENT_BRIGHTNESS
 };
 
 enum VanillaRegion