svn commit: r360025 - head/sys/dev/acpica

[Colin Percival]

Author: cperciva
Date: Thu Apr 16 21:56:52 2020
New Revision: 360025
URL: https://svnweb.freebsd.org/changeset/base/360025

Log:
  Alert devd when acpi_video brightness changes
  
  On my Dell Latitude 7390 laptop, the brightness hotkeys
  (Fn+<up/down arrow>) send ACPI notifications which acpi_video
  handles by adjusting its brightness setting; but ACPI does not
  actually do anything with the backlight.
  
  Announcing brightness changes via devd makes it possible to close
  the loop by triggering the intel_backlight utility to perform the
  required backlight adjustment.
  
  Reviewed by:	imp
  MFC after:	3 days
  Differential Revision:	https://reviews.freebsd.org/D24424

Modified:
  head/sys/dev/acpica/acpi_video.c

Modified: head/sys/dev/acpica/acpi_video.c
==============================================================================
--- head/sys/dev/acpica/acpi_video.c	Thu Apr 16 21:53:17 2020	(r360024)
+++ head/sys/dev/acpica/acpi_video.c	Thu Apr 16 21:56:52 2020	(r360025)
@@ -1036,6 +1036,7 @@ vo_get_brightness(ACPI_HANDLE handle)
 static void
 vo_set_brightness(ACPI_HANDLE handle, int level)
 {
+	char notify_buf[16];
 	ACPI_STATUS status;
 
 	ACPI_SERIAL_ASSERT(video_output);
@@ -1043,6 +1044,8 @@ vo_set_brightness(ACPI_HANDLE handle, int level)
 	if (ACPI_FAILURE(status))
 		printf("can't evaluate %s._BCM - %s\n",
 		       acpi_name(handle), AcpiFormatException(status));
+	snprintf(notify_buf, sizeof(notify_buf), "notify=%d", level);
+	devctl_notify("ACPI", "Video", "brightness", notify_buf);
 }
 
 static UINT32