[src/trunk]: src/sys/dev/acpi Only need to set brightness if reading the init...

[sborrill <sborrill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/316184f8b78b
branches:  trunk
changeset: 1011454:316184f8b78b
user:      sborrill <sborrill%NetBSD.org@localhost>
date:      Tue Jun 30 13:14:21 2020 +0000

description:
Only need to set brightness if reading the initial state fails
to sync firmware and the driver. Avoids black screen at boot time.
Thanks to jmcneill@

diffstat:

 sys/dev/acpi/acpi_display.c |  8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diffs (29 lines):

diff -r 1df9bddf1137 -r 316184f8b78b sys/dev/acpi/acpi_display.c
--- a/sys/dev/acpi/acpi_display.c       Tue Jun 30 11:49:26 2020 +0000
+++ b/sys/dev/acpi/acpi_display.c       Tue Jun 30 13:14:21 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: acpi_display.c,v 1.17 2020/04/28 11:02:37 jmcneill Exp $       */
+/*     $NetBSD: acpi_display.c,v 1.18 2020/06/30 13:14:21 sborrill Exp $       */
 
 /*-
  * Copyright (c) 2010 The NetBSD Foundation, Inc.
@@ -66,7 +66,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: acpi_display.c,v 1.17 2020/04/28 11:02:37 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: acpi_display.c,v 1.18 2020/06/30 13:14:21 sborrill Exp $");
 
 #include <sys/param.h>
 #include <sys/device.h>
@@ -647,8 +647,8 @@
                 * Synchronize ACPI and driver brightness levels, and
                 * check that brightness control is working.
                 */
-               (void)acpidisp_get_brightness(osc, &bc->bc_current);
-               if (acpidisp_set_brightness(osc, bc->bc_current)) {
+               if (acpidisp_get_brightness(osc, &bc->bc_current) &&
+                   acpidisp_set_brightness(osc, bc->bc_current)) {
                        kmem_free(bc->bc_level,
                            bc->bc_level_count * sizeof(*bc->bc_level));
                        kmem_free(bc, sizeof(*bc));