releases/upstream/2.6.24-rc4/0003-ACPI-thinkpad-acpi-add-brightness_force-parameter.patch

   1 From 87cc537a54fc017d998cf603f5fab9ca4a85d668 Mon Sep 17 00:00:00 2001
   2 From: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
   3 Date: Tue, 30 Oct 2007 18:02:07 -0200
   4 Subject: [PATCH 18/23] ACPI: thinkpad-acpi: add brightness_force parameter
   5
   6 Add a "brightness_enable" module parameter that allows the local admin to
   7 force the backlight support to not be enabled.
   8
   9 It can also be used to force the backlight support to be enabled, but that
  10 is currently a no-op as the backlight support is enabled by default when
  11 available.  This will be changed by a different patch.
  12
  13 Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
  14 Signed-off-by: Len Brown <len.brown@intel.com>
  15 ---
  16  Documentation/thinkpad-acpi.txt |    4 ++++
  17  drivers/misc/thinkpad_acpi.c    |    9 +++++++++
  18  drivers/misc/thinkpad_acpi.h    |    1 +
  19  3 files changed, 14 insertions(+), 0 deletions(-)
  20
  21 diff --git a/Documentation/thinkpad-acpi.txt b/Documentation/thinkpad-acpi.txt
  22 index a743bfa..f877c13 100644
  23 --- a/Documentation/thinkpad-acpi.txt
  24 +++ b/Documentation/thinkpad-acpi.txt
  25 @@ -944,6 +944,10 @@ When display backlight brightness controls are available through the
  26  standard ACPI interface, it is best to use it instead of this direct
  27  ThinkPad-specific interface.
  28
  29 +The brightness_enable module parameter can be used to control whether
  30 +the LCD brightness control feature will be enabled when available.
  31 +brightness_enable=0 forces it to be disabled.
  32 +
  33  Procfs notes:
  34
  35         The available commands are:
  36 diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
  37 index 322ba25..56a21e6 100644
  38 --- a/drivers/misc/thinkpad_acpi.c
  39 +++ b/drivers/misc/thinkpad_acpi.c
  40 @@ -3182,6 +3182,12 @@ static int __init brightness_init(struct ibm_init_struct *iibm)
  41
  42         mutex_init(&brightness_mutex);
  43
  44 +       if (!brightness_enable) {
  45 +               dbg_printk(TPACPI_DBG_INIT,
  46 +                          "brightness support disabled by module parameter\n");
  47 +               return 1;
  48 +       }
  49 +
  50         if (!brightness_mode) {
  51                 if (thinkpad_id.vendor == PCI_VENDOR_ID_LENOVO)
  52                         brightness_mode = 2;
  53 @@ -4803,6 +4809,9 @@ module_param_named(fan_control, fan_control_allowed, bool, 0);
  54  static int brightness_mode;
  55  module_param_named(brightness_mode, brightness_mode, int, 0);
  56
  57 +static unsigned int brightness_enable = 2; /* 2 = auto, 0 = no, 1 = yes */
  58 +module_param(brightness_enable, uint, 0);
  59 +
  60  static unsigned int hotkey_report_mode;
  61  module_param(hotkey_report_mode, uint, 0);
  62
  63 diff --git a/drivers/misc/thinkpad_acpi.h b/drivers/misc/thinkpad_acpi.h
  64 index 8ca19c3..8fba2bb 100644
  65 --- a/drivers/misc/thinkpad_acpi.h
  66 +++ b/drivers/misc/thinkpad_acpi.h
  67 @@ -339,6 +339,7 @@ static int bluetooth_write(char *buf);
  68  static struct backlight_device *ibm_backlight_device;
  69  static int brightness_offset = 0x31;
  70  static int brightness_mode;
  71 +static unsigned int brightness_enable; /* 0 = no, 1 = yes, 2 = auto */
  72
  73  static int brightness_init(struct ibm_init_struct *iibm);
  74  static void brightness_exit(void);
  75 --
  76 1.5.3.4
  77