releases/2.6.32.12/thinkpad-acpi-issue-backlight-class-events.patch

   1 From 347a26860e2293b1347996876d3550499c7bb31f Mon Sep 17 00:00:00 2001
   2 From: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
   3 Date: Wed, 9 Dec 2009 01:36:24 +0000
   4 Subject: thinkpad-acpi: issue backlight class events
   5
   6 From: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
   7
   8 commit 347a26860e2293b1347996876d3550499c7bb31f upstream.
   9
  10 Take advantage of the new events capabilities of the backlight class to
  11 notify userspace of backlight changes.
  12
  13 This depends on "backlight: Allow drivers to update the core, and
  14 generate events on changes", by Matthew Garrett.
  15
  16 Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
  17 Cc: Matthew Garrett <mjg@redhat.com>
  18 Cc: Richard Purdie <rpurdie@linux.intel.com>
  19 Signed-off-by: Len Brown <len.brown@intel.com>
  20
  21 ---
  22  Documentation/laptops/thinkpad-acpi.txt |   51 +++++++-------------------------
  23  drivers/platform/x86/thinkpad_acpi.c    |   24 ++++++++++++++-
  24  2 files changed, 35 insertions(+), 40 deletions(-)
  25
  26 --- a/Documentation/laptops/thinkpad-acpi.txt
  27 +++ b/Documentation/laptops/thinkpad-acpi.txt
  28 @@ -460,6 +460,8 @@ event       code    Key             Notes
  29                                 For Lenovo ThinkPads with a new
  30                                 BIOS, it has to be handled either
  31                                 by the ACPI OSI, or by userspace.
  32 +                               The driver does the right thing,
  33 +                               never mess with this.
  34  0x1011 0x10    FN+END          Brightness down.  See brightness
  35                                 up for details.
  36
  37 @@ -582,46 +584,15 @@ with hotkey_report_mode.
  38
  39  Brightness hotkey notes:
  40
  41 -These are the current sane choices for brightness key mapping in
  42 -thinkpad-acpi:
  43 +Don't mess with the brightness hotkeys in a Thinkpad.  If you want
  44 +notifications for OSD, use the sysfs backlight class event support.
  45
  46 -For IBM and Lenovo models *without* ACPI backlight control (the ones on
  47 -which thinkpad-acpi will autoload its backlight interface by default,
  48 -and on which ACPI video does not export a backlight interface):
  49 -
  50 -1. Don't enable or map the brightness hotkeys in thinkpad-acpi, as
  51 -   these older firmware versions unfortunately won't respect the hotkey
  52 -   mask for brightness keys anyway, and always reacts to them.  This
  53 -   usually work fine, unless X.org drivers are doing something to block
  54 -   the BIOS.  In that case, use (3) below.  This is the default mode of
  55 -   operation.
  56 -
  57 -2. Enable the hotkeys, but map them to something else that is NOT
  58 -   KEY_BRIGHTNESS_UP/DOWN or any other keycode that would cause
  59 -   userspace to try to change the backlight level, and use that as an
  60 -   on-screen-display hint.
  61 -
  62 -3. IF AND ONLY IF X.org drivers find a way to block the firmware from
  63 -   automatically changing the brightness, enable the hotkeys and map
  64 -   them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN, and feed that to
  65 -   something that calls xbacklight.  thinkpad-acpi will not be able to
  66 -   change brightness in that case either, so you should disable its
  67 -   backlight interface.
  68 -
  69 -For Lenovo models *with* ACPI backlight control:
  70 -
  71 -1. Load up ACPI video and use that.  ACPI video will report ACPI
  72 -   events for brightness change keys.  Do not mess with thinkpad-acpi
  73 -   defaults in this case.  thinkpad-acpi should not have anything to do
  74 -   with backlight events in a scenario where ACPI video is loaded:
  75 -   brightness hotkeys must be disabled, and the backlight interface is
  76 -   to be kept disabled as well.  This is the default mode of operation.
  77 -
  78 -2. Do *NOT* load up ACPI video, enable the hotkeys in thinkpad-acpi,
  79 -   and map them to KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN.  Process
  80 -   these keys on userspace somehow (e.g. by calling xbacklight).
  81 -   The driver will do this automatically if it detects that ACPI video
  82 -   has been disabled.
  83 +The driver will issue KEY_BRIGHTNESS_UP and KEY_BRIGHTNESS_DOWN events
  84 +automatically for the cases were userspace has to do something to
  85 +implement brightness changes.  When you override these events, you will
  86 +either fail to handle properly the ThinkPads that require explicit
  87 +action to change backlight brightness, or the ThinkPads that require
  88 +that no action be taken to work properly.
  89
  90
  91  Bluetooth
  92 @@ -1465,3 +1436,5 @@ Sysfs interface changelog:
  93                 and it is always able to disable hot keys.  Very old
  94                 thinkpads are properly supported.  hotkey_bios_mask
  95                 is deprecated and marked for removal.
  96 +
  97 +0x020600:      Marker for backlight change event support.
  98 --- a/drivers/platform/x86/thinkpad_acpi.c
  99 +++ b/drivers/platform/x86/thinkpad_acpi.c
 100 @@ -22,7 +22,7 @@
 101   */
 102
 103  #define TPACPI_VERSION "0.23"
 104 -#define TPACPI_SYSFS_VERSION 0x020500
 105 +#define TPACPI_SYSFS_VERSION 0x020600
 106
 107  /*
 108   *  Changelog:
 109 @@ -6083,6 +6083,12 @@ static int brightness_get(struct backlig
 110         return status & TP_EC_BACKLIGHT_LVLMSK;
 111  }
 112
 113 +static void tpacpi_brightness_notify_change(void)
 114 +{
 115 +       backlight_force_update(ibm_backlight_device,
 116 +                              BACKLIGHT_UPDATE_HOTKEY);
 117 +}
 118 +
 119  static struct backlight_ops ibm_backlight_data = {
 120         .get_brightness = brightness_get,
 121         .update_status  = brightness_update_status,
 122 @@ -6237,6 +6243,12 @@ static int __init brightness_init(struct
 123         ibm_backlight_device->props.brightness = b & TP_EC_BACKLIGHT_LVLMSK;
 124         backlight_update_status(ibm_backlight_device);
 125
 126 +       vdbg_printk(TPACPI_DBG_INIT | TPACPI_DBG_BRGHT,
 127 +                       "brightness: registering brightness hotkeys "
 128 +                       "as change notification\n");
 129 +       tpacpi_hotkey_driver_mask_set(hotkey_driver_mask
 130 +                               | TP_ACPI_HKEY_BRGHTUP_MASK
 131 +                               | TP_ACPI_HKEY_BRGHTDWN_MASK);;
 132         return 0;
 133  }
 134
 135 @@ -6313,6 +6325,9 @@ static int brightness_write(char *buf)
 136          * Doing it this way makes the syscall restartable in case of EINTR
 137          */
 138         rc = brightness_set(level);
 139 +       if (!rc && ibm_backlight_device)
 140 +               backlight_force_update(ibm_backlight_device,
 141 +                                       BACKLIGHT_UPDATE_SYSFS);
 142         return (rc == -EINTR)? -ERESTARTSYS : rc;
 143  }
 144
 145 @@ -7712,6 +7727,13 @@ static struct ibm_struct fan_driver_data
 146   */
 147  static void tpacpi_driver_event(const unsigned int hkey_event)
 148  {
 149 +       if (ibm_backlight_device) {
 150 +               switch (hkey_event) {
 151 +               case TP_HKEY_EV_BRGHT_UP:
 152 +               case TP_HKEY_EV_BRGHT_DOWN:
 153 +                       tpacpi_brightness_notify_change();
 154 +               }
 155 +       }
 156  }
 157
 158