releases/upstream/2.6.26-rc1/0005-ACPI-thinkpad-acpi-rate-limit-CMOS-EC-unsynced-err.patch

   1 From 2d5e94d7ca315f859a0eee1366838e8ad34dd7b2 Mon Sep 17 00:00:00 2001
   2 From: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
   3 Date: Sat, 26 Apr 2008 01:02:20 -0300
   4 Subject: ACPI: thinkpad-acpi: rate-limit CMOS/EC unsynced error messages
   5
   6 If userspace applications mess with the CMOS NVRAM, or something causes
   7 both the ACPI firmware and thinkpad-acpi to try to change the brightness at
   8 the same time, it is possible to have the CMOS and EC registers for the
   9 current brightness go out of sync.
  10
  11 Should that happen, thinkpad-acpi could be really obnoxious when using a
  12 brightness_mode of 3 (both EC and CMOS).  Instead of complaining a massive
  13 number of times, make sure to complain only once until EC and CMOS are back
  14 in sync.
  15
  16 Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
  17 Cc: Joerg Platte <lists@naasa.net>
  18 Signed-off-by: Len Brown <len.brown@intel.com>
  19 ---
  20  drivers/misc/thinkpad_acpi.c |   22 +++++++++++++++-------
  21  1 files changed, 15 insertions(+), 7 deletions(-)
  22
  23 diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
  24 index 601dbe8..7dc6b73 100644
  25 --- a/drivers/misc/thinkpad_acpi.c
  26 +++ b/drivers/misc/thinkpad_acpi.c
  27 @@ -239,6 +239,7 @@ static struct {
  28
  29  static struct {
  30         u16 hotkey_mask_ff:1;
  31 +       u16 bright_cmos_ec_unsync:1;
  32  } tp_warned;
  33
  34  struct thinkpad_id_data {
  35 @@ -4323,13 +4324,20 @@ static int brightness_get(struct backlight_device *bd)
  36                 level = lcmos;
  37         }
  38
  39 -       if (brightness_mode == 3 && lec != lcmos) {
  40 -               printk(TPACPI_ERR
  41 -                       "CMOS NVRAM (%u) and EC (%u) do not agree "
  42 -                       "on display brightness level\n",
  43 -                       (unsigned int) lcmos,
  44 -                       (unsigned int) lec);
  45 -               return -EIO;
  46 +       if (brightness_mode == 3) {
  47 +               if (lec == lcmos)
  48 +                       tp_warned.bright_cmos_ec_unsync = 0;
  49 +               else {
  50 +                       if (!tp_warned.bright_cmos_ec_unsync) {
  51 +                               printk(TPACPI_ERR
  52 +                                       "CMOS NVRAM (%u) and EC (%u) do not "
  53 +                                       "agree on display brightness level\n",
  54 +                                       (unsigned int) lcmos,
  55 +                                       (unsigned int) lec);
  56 +                               tp_warned.bright_cmos_ec_unsync = 1;
  57 +                       }
  58 +                       return -EIO;
  59 +               }
  60         }
  61
  62         return level;
  63 --
  64 1.5.4.4
  65