From 1cfb72f33ade965ca769721b9e248ca916482cef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Guido=20G=C3=BCnther?= <agx@sigxcpu.org>
Date: Sat, 26 Sep 2020 12:19:50 +0200
Subject: [PATCH] Add torch support

This is modeled like KbdBacklight.

Taken from: https://gitlab.freedesktop.org/upower/upower/-/merge_requests/50
---
 dbus/Makefile.am                      |  11 +
 dbus/org.freedesktop.UPower.Torch.xml | 148 ++++++++++
 doc/Makefile.am                       |   9 +-
 src/Makefile.am                       |   4 +-
 src/org.freedesktop.UPower.conf.in    |   4 +
 src/up-main.c                         |   5 +
 src/up-torch.c                        | 388 ++++++++++++++++++++++++++
 src/up-torch.h                        |  40 +++
 8 files changed, 607 insertions(+), 2 deletions(-)
 create mode 100644 dbus/org.freedesktop.UPower.Torch.xml
 create mode 100644 src/up-torch.c
 create mode 100644 src/up-torch.h

diff --git a/dbus/Makefile.am b/dbus/Makefile.am
index 017c7eb..264761c 100644
--- a/dbus/Makefile.am
+++ b/dbus/Makefile.am
@@ -17,6 +17,8 @@ BUILT_SOURCES =		\
 	up-device-generated.c		\
 	up-kbd-backlight-generated.h	\
 	up-kbd-backlight-generated.c	\
+	up-torch-generated.h		\
+	up-torch-generated.c		\
 	up-wakeups-generated.h		\
 	up-wakeups-generated.c
 
@@ -46,6 +48,14 @@ up-kbd-backlight-generated.h: org.freedesktop.UPower.KbdBacklight.xml Makefile.a
 	$(srcdir)/org.freedesktop.UPower.KbdBacklight.xml
 up-kbd-backlight-generated.c: up-kbd-backlight-generated.h
 
+up-torch-generated.h: org.freedesktop.UPower.Torch.xml Makefile.am
+	$(AM_V_GEN) gdbus-codegen --interface-prefix org.freedesktop.UPower.Torch. \
+	--generate-c-code up-torch-generated \
+	--c-namespace Up \
+	--annotate "org.freedesktop.UPower.Torch" "org.gtk.GDBus.C.Name" ExportedTorch \
+	$(srcdir)/org.freedesktop.UPower.Torch.xml
+up-torch-generated.c: up-torch-generated.h
+
 up-wakeups-generated.h: org.freedesktop.UPower.Wakeups.xml Makefile.am
 	$(AM_V_GEN) gdbus-codegen --interface-prefix org.freedesktop.UPower.Wakeups. \
 	--generate-c-code up-wakeups-generated \
@@ -59,6 +69,7 @@ dist_dbusif_DATA =						\
 	org.freedesktop.UPower.xml				\
 	org.freedesktop.UPower.Device.xml			\
 	org.freedesktop.UPower.KbdBacklight.xml			\
+	org.freedesktop.UPower.Torch.xml			\
 	org.freedesktop.UPower.Wakeups.xml
 
 -include $(top_srcdir)/git.mk
diff --git a/dbus/org.freedesktop.UPower.Torch.xml b/dbus/org.freedesktop.UPower.Torch.xml
new file mode 100644
index 0000000..4f7bfd9
--- /dev/null
+++ b/dbus/org.freedesktop.UPower.Torch.xml
@@ -0,0 +1,148 @@
+<!DOCTYPE node PUBLIC
+"-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
+"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd" [
+  <!ENTITY ERROR_GENERAL "org.freedesktop.UPower.GeneralError">
+]>
+<node name="/" xmlns:doc="http://www.freedesktop.org/dbus/1.0/doc.dtd">
+  <interface name="org.freedesktop.UPower.Torch">
+    <doc:doc>
+      <doc:description>
+        <doc:para>
+          org.freedesktop.UPower.Torch is a DBus interface implemented
+          by UPower.
+	  It allows a torch (if present) to be controlled.
+        </doc:para>
+      </doc:description>
+    </doc:doc>
+
+    <!-- ************************************************************ -->
+    <method name="GetMaxBrightness">
+      <arg name="value" direction="out" type="i">
+        <doc:doc>
+          <doc:summary>
+            The maximum value of the torch brightness.
+          </doc:summary>
+        </doc:doc>
+      </arg>
+      <doc:doc>
+        <doc:description>
+          <doc:para>
+            Get the maximum brightness level for the torch.
+          </doc:para>
+        </doc:description>
+        <doc:errors>
+          <doc:error name="&ERROR_GENERAL;">if an error occured while getting the maximum brightness</doc:error>
+        </doc:errors>
+      </doc:doc>
+    </method>
+
+    <!-- ************************************************************ -->
+    <method name="GetBrightness">
+      <arg name="value" direction="out" type="i">
+        <doc:doc>
+          <doc:summary>
+            The current value of the torch brightness.
+          </doc:summary>
+        </doc:doc>
+      </arg>
+      <doc:doc>
+        <doc:description>
+          <doc:para>
+            Get the brightness level of the torch.
+          </doc:para>
+        </doc:description>
+        <doc:errors>
+          <doc:error name="&ERROR_GENERAL;">if an error occured while getting the brightness</doc:error>
+        </doc:errors>
+      </doc:doc>
+    </method>
+
+    <!-- ************************************************************ -->
+    <method name="SetBrightness">
+      <arg name="value" direction="in" type="i">
+        <doc:doc>
+          <doc:summary>
+            The value to set the torch brightness.
+          </doc:summary>
+        </doc:doc>
+      </arg>
+      <doc:doc>
+        <doc:description>
+          <doc:para>
+            Set the brightness level of the torch.
+          </doc:para>
+        </doc:description>
+        <doc:errors>
+          <doc:error name="&ERROR_GENERAL;">if an error occured while setting the brightness</doc:error>
+        </doc:errors>
+      </doc:doc>
+    </method>
+
+    <!-- ************************************************************ -->
+    <signal name="BrightnessChanged">
+      <arg name="value" direction="out" type="i">
+        <doc:doc>
+          <doc:summary>
+            The new brightness value of the torch.
+          </doc:summary>
+        </doc:doc>
+      </arg>
+      <doc:doc>
+        <doc:description>
+          <doc:para>
+	    The torch brightness level has changed.
+          </doc:para>
+        </doc:description>
+      </doc:doc>
+    </signal>
+
+    <signal name="BrightnessChangedWithSource">
+      <arg name="value" direction="out" type="i">
+        <doc:doc>
+          <doc:summary>
+            The new brightness value of the torch.
+          </doc:summary>
+        </doc:doc>
+      </arg>
+      <arg name="source" direction="out" type="s">
+        <doc:doc>
+          <doc:summary>
+            Source of the torch brightness change, either
+            "external" if SetBrightness was called, or "internal" if the
+            hardware changed the keyboard brightness itself.
+          </doc:summary>
+        </doc:doc>
+      </arg>
+      <doc:doc>
+        <doc:description>
+          <doc:para>
+	    The torch brightness level has changed including
+	    information about the source of the change.
+          </doc:para>
+        </doc:description>
+      </doc:doc>
+    </signal>
+    <!-- ************************************************************ -->
+    <property name="MaxBrightness" type="i" access="read">
+      <doc:doc>
+        <doc:description>
+          <doc:para>
+	    The maximum value of the torch brightness.
+          </doc:para>
+        </doc:description>
+      </doc:doc>
+    </property>
+
+    <property name="Brightness" type="i" access="read">
+      <doc:doc>
+        <doc:description>
+          <doc:para>
+            The current value of the torch brightness.
+          </doc:para>
+        </doc:description>
+      </doc:doc>
+    </property>
+
+  </interface>
+
+</node>
diff --git a/doc/Makefile.am b/doc/Makefile.am
index 2c20415..718c057 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -65,6 +65,11 @@ org.freedesktop.UPower.KbdBacklight.ref.xml : $(top_srcdir)/dbus/org.freedesktop
 	echo "<?xml version=\"1.0\"?>""<!DOCTYPE refentry PUBLIC \"-//OASIS//DTD DocBook XML V4.1.2//EN\" \"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd\">" > $@
 	$(XSLTPROC) $(top_srcdir)/doc/spec-to-docbook.xsl $< | tail -n +2 >> $@
 
+org.freedesktop.UPower.Torch.ref.xml : $(top_srcdir)/dbus/org.freedesktop.UPower.Torch.xml $(top_srcdir)/doc/spec-to-docbook.xsl
+	if $(AM_V_P); then set -x; else echo " GEN   $@"; fi
+	echo "<?xml version=\"1.0\"?>""<!DOCTYPE refentry PUBLIC \"-//OASIS//DTD DocBook XML V4.1.2//EN\" \"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd\">" > $@
+	$(XSLTPROC) $(top_srcdir)/doc/spec-to-docbook.xsl $< | tail -n +2 >> $@
+
 org.freedesktop.UPower.Wakeups.ref.xml : $(top_srcdir)/dbus/org.freedesktop.UPower.Wakeups.xml $(top_srcdir)/doc/spec-to-docbook.xsl
 	if $(AM_V_P); then set -x; else echo " GEN   $@"; fi
 	echo "<?xml version=\"1.0\"?>""<!DOCTYPE refentry PUBLIC \"-//OASIS//DTD DocBook XML V4.1.2//EN\" \"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd\">" > $@
@@ -75,7 +80,8 @@ EXTRA_DIST = spec-to-docbook.xsl dbus-introspect-docs.dtd
 BUILT_SOURCES =							\
 	org.freedesktop.UPower.ref.xml			\
 	org.freedesktop.UPower.Device.ref.xml		\
-	org.freedesktop.UPower.KbdBacklight.ref.xml
+	org.freedesktop.UPower.KbdBacklight.ref.xml	\
+	org.freedesktop.UPower.Torch.ref.xml
 
 # Non-autogenerated SGML files to be included in $(DOC_MAIN_SGML_FILE)
 content_files =  			    				\
@@ -102,6 +108,7 @@ MAINTAINERCLEANFILES =		\
 DISTCLEANFILES =					\
 	org.freedesktop.UPower.Device.ref.xml		\
 	org.freedesktop.UPower.KbdBacklight.ref.xml	\
+	org.freedesktop.UPower.Torch.ref.xml		\
 	org.freedesktop.UPower.ref.xml			\
 	upowerd.xml					\
 	upower.xml					\
diff --git a/src/Makefile.am b/src/Makefile.am
index 3400139..f022efb 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -60,7 +60,9 @@ upowerd_SOURCES =						\
 	up-backend.h						\
 	up-native.h						\
 	up-main.c						\
-	up-backend-bsd-private.h			\
+	up-torch.h						\
+	up-torch.c						\
+	up-backend-bsd-private.h				\
 	$(BUILT_SOURCES)
 
 upowerd_CPPFLAGS =						\
diff --git a/src/org.freedesktop.UPower.conf.in b/src/org.freedesktop.UPower.conf.in
index 5a6c660..ef60549 100644
--- a/src/org.freedesktop.UPower.conf.in
+++ b/src/org.freedesktop.UPower.conf.in
@@ -21,6 +21,8 @@
            send_interface="org.freedesktop.DBus.Properties"/>
     <allow send_destination="org.freedesktop.UPower.KbdBacklight"
            send_interface="org.freedesktop.DBus.Properties"/>
+    <allow send_destination="org.freedesktop.UPower.Torch"
+           send_interface="org.freedesktop.DBus.Properties"/>
     <allow send_destination="org.freedesktop.UPower.Wakeups"
            send_interface="org.freedesktop.DBus.Properties"/>
 
@@ -28,6 +30,8 @@
            send_interface="org.freedesktop.UPower"/>
     <allow send_destination="org.freedesktop.UPower"
            send_interface="org.freedesktop.UPower.Device"/>
+    <allow send_destination="org.freedesktop.UPower"
+           send_interface="org.freedesktop.UPower.Torch"/>
     <allow send_destination="org.freedesktop.UPower"
            send_interface="org.freedesktop.UPower.KbdBacklight"/>
     <allow send_destination="org.freedesktop.UPower"
diff --git a/src/up-main.c b/src/up-main.c
index 0619c50..f9ebaae 100644
--- a/src/up-main.c
+++ b/src/up-main.c
@@ -38,12 +38,14 @@
 
 #include "up-daemon.h"
 #include "up-kbd-backlight.h"
+#include "up-torch.h"
 #include "up-wakeups.h"
 
 #define DEVKIT_POWER_SERVICE_NAME "org.freedesktop.UPower"
 
 typedef struct UpState {
 	UpKbdBacklight *kbd_backlight;
+	UpTorch *torch;
 	UpWakeups *wakeups;
 	UpDaemon *daemon;
 	GMainLoop *loop;
@@ -55,6 +57,7 @@ up_state_free (UpState *state)
 	up_daemon_shutdown (state->daemon);
 
 	g_clear_object (&state->kbd_backlight);
+	g_clear_object (&state->torch);
 	g_clear_object (&state->wakeups);
 	g_clear_object (&state->daemon);
 	g_clear_pointer (&state->loop, g_main_loop_unref);
@@ -68,6 +71,7 @@ up_state_new (void)
 	UpState *state = g_new0 (UpState, 1);
 
 	state->kbd_backlight = up_kbd_backlight_new ();
+	state->torch = up_torch_new ();
 	state->wakeups = up_wakeups_new ();
 	state->daemon = up_daemon_new ();
 	state->loop = g_main_loop_new (NULL, FALSE);
@@ -86,6 +90,7 @@ up_main_bus_acquired (GDBusConnection *connection,
 	UpState *state = user_data;
 
 	up_kbd_backlight_register (state->kbd_backlight, connection);
+	up_torch_register (state->torch, connection);
 	up_wakeups_register (state->wakeups, connection);
 	if (!up_daemon_startup (state->daemon, connection)) {
 		g_warning ("Could not startup; bailing out");
diff --git a/src/up-torch.c b/src/up-torch.c
new file mode 100644
index 0000000..8705041
--- /dev/null
+++ b/src/up-torch.c
@@ -0,0 +1,388 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ *
+ * Copyright (C) 2020 Guido Günther <agx@sigxcpu.org>
+ *               2008 Richard Hughes <richard@hughsie.com>
+ *               2010 Alex Murray <murray.alex@gmail.com>
+ *
+ * Licensed under the GNU General Public License Version 2
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib/gi18n.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <dirent.h>
+#include <errno.h>
+
+#include "up-torch.h"
+#include "up-daemon.h"
+#include "up-types.h"
+
+static void     up_torch_finalize   (GObject	*object);
+
+struct _UpTorch
+{
+	UpExportedTorchSkeleton  parent;
+
+	gint			 fd;
+	gint			 fd_hw_changed;
+	GIOChannel		*channel_hw_changed;
+	gint			 max_brightness;
+};
+
+G_DEFINE_TYPE (UpTorch, up_torch, UP_TYPE_EXPORTED_TORCH_SKELETON)
+
+/**
+ * up_torch_emit_change:
+ **/
+static void
+up_torch_emit_change(UpTorch *torch, int value, const char *source)
+{
+	g_object_set (torch, "brightness", value, NULL);
+	up_exported_torch_emit_brightness_changed (UP_EXPORTED_TORCH (torch), value);
+	up_exported_torch_emit_brightness_changed_with_source (UP_EXPORTED_TORCH (torch), value, source);
+}
+
+/**
+ * up_torch_brightness_read:
+ **/
+static gint
+up_torch_brightness_read (UpTorch *torch, int fd)
+{
+	gchar buf[16];
+	gchar *end = NULL;
+	ssize_t len;
+	gint64 brightness = -1;
+
+	g_return_val_if_fail (fd >= 0, brightness);
+
+	lseek (fd, 0, SEEK_SET);
+	len = read (fd, buf, G_N_ELEMENTS (buf) - 1);
+
+	if (len > 0) {
+		buf[len] = '\0';
+		brightness = g_ascii_strtoll (buf, &end, 10);
+
+		if (brightness < 0 ||
+		    brightness > torch->max_brightness ||
+		    end == buf) {
+			brightness = -1;
+			g_warning ("failed to convert brightness: %s", buf);
+		}
+	}
+
+	g_object_set (torch, "brightness", brightness, NULL);
+	return brightness;
+}
+
+/**
+ * up_torch_brightness_write:
+ **/
+static gboolean
+up_torch_brightness_write (UpTorch *torch, gint value)
+{
+	g_autofree gchar *text = NULL;
+	gint retval;
+	gint length;
+	gboolean ret = TRUE;
+
+	/* write new values to backlight */
+	if (torch->fd < 0) {
+		g_warning ("cannot write to torch as file not open");
+		return FALSE;
+	}
+
+	/* limit to between 0 and max */
+	value = CLAMP (value, 0, torch->max_brightness);
+
+	/* convert to text */
+	text = g_strdup_printf ("%i", value);
+	length = strlen (text);
+
+	/* write to file */
+	lseek (torch->fd, 0, SEEK_SET);
+	retval = write (torch->fd, text, length);
+	if (retval != length) {
+		g_warning ("writing '%s' to device failed", text);
+		return FALSE;
+	}
+
+	/* emit signal */
+	up_torch_emit_change (torch, value, "external");
+
+	return ret;
+}
+
+/**
+ * up_torch_get_brightness:
+ *
+ * Gets the current brightness
+ **/
+static gboolean
+up_torch_get_brightness (UpExportedTorch *skeleton,
+				 GDBusMethodInvocation *invocation,
+				 UpTorch *torch)
+{
+	gint brightness;
+
+	brightness = up_torch_brightness_read (torch, torch->fd);
+
+	if (brightness >= 0) {
+		up_exported_torch_complete_get_brightness (skeleton, invocation,
+								   brightness);
+	} else {
+		g_dbus_method_invocation_return_error (invocation,
+						       UP_DAEMON_ERROR, UP_DAEMON_ERROR_GENERAL,
+						       "error reading brightness");
+	}
+
+	return TRUE;
+}
+
+/**
+ * up_torch_get_max_brightness:
+ *
+ * Gets the max brightness
+ **/
+static gboolean
+up_torch_get_max_brightness (UpExportedTorch *skeleton,
+				     GDBusMethodInvocation *invocation,
+				     UpTorch *torch)
+{
+	up_exported_torch_complete_get_max_brightness (skeleton, invocation,
+							       torch->max_brightness);
+	return TRUE;
+}
+
+/**
+ * up_torch_set_brightness:
+ **/
+static gboolean
+up_torch_set_brightness (UpExportedTorch *skeleton,
+				 GDBusMethodInvocation *invocation,
+				 gint value,
+				 UpTorch *torch)
+{
+	gboolean ret = FALSE;
+
+	g_debug ("setting brightness to %i", value);
+	ret = up_torch_brightness_write (torch, value);
+
+	if (ret) {
+		up_exported_torch_complete_set_brightness (skeleton, invocation);
+	} else {
+		g_dbus_method_invocation_return_error (invocation,
+						       UP_DAEMON_ERROR, UP_DAEMON_ERROR_GENERAL,
+						       "error writing brightness %d", value);
+	}
+
+	return TRUE;
+}
+
+/**
+ * up_torch_class_init:
+ **/
+static void
+up_torch_class_init (UpTorchClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (klass);
+	object_class->finalize = up_torch_finalize;
+}
+
+/**
+ * up_torch_event_io:
+ **/
+static gboolean
+up_torch_event_io (GIOChannel *channel, GIOCondition condition, gpointer data)
+{
+	UpTorch *torch = (UpTorch*) data;
+	gint brightness;
+
+	if (!(condition & G_IO_PRI))
+		return FALSE;
+
+	brightness = up_torch_brightness_read (torch, torch->fd_hw_changed);
+	if (brightness < 0 && errno == ENODEV)
+		return FALSE;
+
+	if (brightness >= 0)
+		up_torch_emit_change (torch, brightness, "internal");
+
+	return TRUE;
+}
+
+/**
+ * up_torch_find:
+ **/
+static gboolean
+up_torch_find (UpTorch *torch)
+{
+	gboolean ret;
+	gboolean found = FALSE;
+	GDir *dir;
+	const gchar *filename;
+	gchar *end = NULL;
+	g_autofree gchar *dir_path = NULL;
+	g_autofree gchar *path_max = NULL;
+	g_autofree gchar *path_now = NULL;
+	g_autofree gchar *path_hw_changed = NULL;
+	g_autofree gchar *buf_max = NULL;
+	g_autofree gchar *buf_now = NULL;
+	GError *error = NULL;
+
+	torch->fd = -1;
+
+	/* open directory */
+	dir = g_dir_open ("/sys/class/leds", 0, &error);
+	if (dir == NULL) {
+		if (!g_error_matches (error, G_FILE_ERROR, G_FILE_ERROR_NOENT))
+			g_warning ("failed to open directory: %s", error->message);
+		g_error_free (error);
+		goto out;
+	}
+
+	/* find a led device that is a torch */
+	while ((filename = g_dir_read_name (dir)) != NULL) {
+		if (g_strstr_len (filename, -1, "torch") != NULL ||
+		    g_strstr_len (filename, -1, "flash") != NULL) {
+			dir_path = g_build_filename ("/sys/class/leds",
+						    filename, NULL);
+			break;
+		}
+	}
+
+	/* nothing found */
+	if (dir_path == NULL)
+		goto out;
+
+	/* read max brightness */
+	path_max = g_build_filename (dir_path, "max_brightness", NULL);
+	ret = g_file_get_contents (path_max, &buf_max, NULL, &error);
+	if (!ret) {
+		g_warning ("failed to get max brightness: %s", error->message);
+		g_error_free (error);
+		goto out;
+	}
+	torch->max_brightness = g_ascii_strtoull (buf_max, &end, 10);
+	if (torch->max_brightness == 0 && end == buf_max) {
+		g_warning ("failed to convert max brightness: %s", buf_max);
+		goto out;
+	}
+	g_object_set (torch, "max-brightness", torch->max_brightness, NULL);
+
+	/* open the brightness file for read and write operations */
+	path_now = g_build_filename (dir_path, "brightness", NULL);
+	torch->fd = open (path_now, O_RDWR);
+
+	/* read brightness and check if it has an acceptable value */
+	if (up_torch_brightness_read (torch, torch->fd) < 0)
+		goto out;
+
+	path_hw_changed = g_build_filename (dir_path, "brightness_hw_changed", NULL);
+	torch->fd_hw_changed = open (path_hw_changed, O_RDONLY);
+	if (torch->fd_hw_changed >= 0) {
+		torch->channel_hw_changed = g_io_channel_unix_new (torch->fd_hw_changed);
+		g_io_add_watch (torch->channel_hw_changed,
+				G_IO_PRI, up_torch_event_io, torch);
+	}
+
+	/* success */
+	found = TRUE;
+out:
+	if (dir != NULL)
+		g_dir_close (dir);
+	return found;
+}
+
+/**
+ * up_torch_init:
+ **/
+static void
+up_torch_init (UpTorch *torch)
+{
+	g_signal_connect (torch, "handle-get-brightness",
+			  G_CALLBACK (up_torch_get_brightness), torch);
+	g_signal_connect (torch, "handle-get-max-brightness",
+			  G_CALLBACK (up_torch_get_max_brightness), torch);
+	g_signal_connect (torch, "handle-set-brightness",
+			  G_CALLBACK (up_torch_set_brightness), torch);
+}
+
+/**
+ * up_torch_finalize:
+ **/
+static void
+up_torch_finalize (GObject *object)
+{
+	UpTorch *torch;
+
+	g_return_if_fail (object != NULL);
+	g_return_if_fail (UP_IS_TORCH (object));
+
+	torch = UP_TORCH (object);
+
+	if (torch->channel_hw_changed) {
+		g_io_channel_shutdown (torch->channel_hw_changed, FALSE, NULL);
+		g_io_channel_unref (torch->channel_hw_changed);
+	}
+
+	if (torch->fd_hw_changed >= 0)
+		close (torch->fd_hw_changed);
+
+	/* close file */
+	if (torch->fd >= 0)
+		close (torch->fd);
+
+	G_OBJECT_CLASS (up_torch_parent_class)->finalize (object);
+}
+
+/**
+ * up_torch_new:
+ **/
+UpTorch *
+up_torch_new (void)
+{
+	return g_object_new (UP_TYPE_TORCH, NULL);
+}
+
+void
+up_torch_register (UpTorch *torch,
+			   GDBusConnection *connection)
+{
+	g_autoptr(GError) error = NULL;
+
+	/* find a kbd backlight in sysfs */
+	if (!up_torch_find (torch)) {
+		g_debug ("cannot find a torch");
+		return;
+	}
+
+	g_dbus_interface_skeleton_export (G_DBUS_INTERFACE_SKELETON (torch),
+					  connection,
+					  "/org/freedesktop/UPower/Torch",
+					  &error);
+
+	if (error != NULL) {
+		g_warning ("Cannot export Torch object to bus: %s", error->message);
+	}
+}
diff --git a/src/up-torch.h b/src/up-torch.h
new file mode 100644
index 0000000..e84c9f5
--- /dev/null
+++ b/src/up-torch.h
@@ -0,0 +1,40 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ *
+ * Copyright (C) 2008 Richard Hughes <richard@hughsie.com>
+ *               2010 Alex Murray <murray.alex@gmail.com>
+ *               2010 Alex Murray <murray.alex@gmail.com>
+ *
+ * Licensed under the GNU General Public License Version 2
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef __UP_TORCH_H
+#define __UP_TORCH_H
+
+#include <dbus/up-torch-generated.h>
+
+G_BEGIN_DECLS
+
+#define UP_TYPE_TORCH		(up_torch_get_type ())
+G_DECLARE_FINAL_TYPE (UpTorch, up_torch, UP, TORCH, UpExportedTorchSkeleton);
+
+UpTorch	*up_torch_new		(void);
+void	 up_torch_register	(UpTorch *torch,
+				 GDBusConnection *connection);
+
+G_END_DECLS
+
+#endif	/* __UP_TORCH_H */
-- 
2.20.1

