configure: Allow disabling control over the backlight

Some OS prefer to control the backlight themselves through another
daemon and so do not want X interfering.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/configure.ac b/configure.ac
index 8e3dbf7..fdadf4b 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -69,11 +69,20 @@ case $host_os in
     ;;
 esac
 
+AC_ARG_ENABLE(backlight,
+              AS_HELP_STRING([--disable-backlight],
+                            [Enable control over the backlight [default=yes]]),
+              [backlight="$enableval"],
+              [backlight="yes"])
+if test "x$backlight" = "xyes"; then
+       AC_DEFINE(USE_BACKLIGHT, 1, [Enable control of the backlight])
+fi
+
 AC_ARG_ENABLE(backlight-helper,
               AS_HELP_STRING([--disable-backlight-helper],
                             [Enable building the backlight helper executable for running X under a normal user [default=auto]]),
               [backlight_helper="$enableval"],)
-AM_CONDITIONAL(BUILD_BACKLIGHT_HELPER, [test "x$backlight_helper" = "xyes"])
+AM_CONDITIONAL(BUILD_BACKLIGHT_HELPER, [test "x$backlight" = "xyes" -a "x$backlight_helper" = "xyes"])
 if test "x$backlight_helper" = "xyes"; then
        tools_msg="$tools_msg xf86-video-intel-backlight-helper"
        AC_DEFINE(USE_BACKLIGHT_HELPER, 1, [Enable use of the backlight helper interfaces])

diff --git a/src/sna/sna_display.c b/src/sna/sna_display.c
index 34e31ec..943118b 100644 (file)
--- a/src/sna/sna_display.c
+++ b/src/sna/sna_display.c
@@ -478,6 +478,10 @@ static void sna_backlight_pre_init(struct sna *sna)
        struct udev *u;
        struct udev_monitor *mon;
 
+#if !USE_BACKLIGHT
+       return;
+#endif
+
        u = udev_new();
        if (!u)
                return;
@@ -606,6 +610,10 @@ sna_output_backlight_init(xf86OutputPtr output)
        MessageType from;
        char *best_iface;
 
+#if !USE_BACKLIGHT
+       return;
+#endif
+
        from = X_CONFIG;
        best_iface = has_user_backlight_override(output);
        if (best_iface)

diff --git a/src/uxa/intel_display.c b/src/uxa/intel_display.c
index 95ddcc8..5bb9d72 100644 (file)
--- a/src/uxa/intel_display.c
+++ b/src/uxa/intel_display.c
@@ -186,6 +186,10 @@ intel_output_backlight_init(xf86OutputPtr output)
        intel_screen_private *intel = intel_get_screen_private(output->scrn);
        char *str;
 
+#if !USE_BACKLIGHT
+       return;
+#endif
+
        str = xf86GetOptValString(intel->Options, OPTION_BACKLIGHT);
        if (str != NULL) {
                if (backlight_exists(str) != BL_NONE) {