releases/upstream/2.6.29-rc2/0012-ACPI-thinkpad-acpi-clean-up-fan-subdriver-quirk.patch

   1 From 1c2ece758a36b48133717e4db060fbe8fa52c5cd Mon Sep 17 00:00:00 2001
   2 From: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
   3 Date: Sun, 11 Jan 2009 03:01:08 -0200
   4 Subject: ACPI: thinkpad-acpi: clean-up fan subdriver quirk
   5
   6 Better document the Unitialized HFSP quirk, and modularize it a bit.
   7 This makes the code flow easier to read and reduces LOC.
   8
   9 Apply the Unitialized HFSP closer to the source (i.e. inside the
  10 get_fan_status()), this fixes a harmless buglet where at driver init
  11 with the quirk active, the user could set the hwmon pwm1 attribute and
  12 switch out of pwm1_mode=2 to pwm1_mode=0 without changing pwm1_mode
  13 directly.
  14
  15 Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
  16 Cc: Tino Keitel <tino.keitel@tikei.de>
  17 Signed-off-by: Len Brown <len.brown@intel.com>
  18 ---
  19  drivers/platform/x86/thinkpad_acpi.c |  109 ++++++++++++++++++----------------
  20  1 files changed, 58 insertions(+), 51 deletions(-)
  21
  22 diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
  23 index d7d41ae..213219d 100644
  24 --- a/drivers/platform/x86/thinkpad_acpi.c
  25 +++ b/drivers/platform/x86/thinkpad_acpi.c
  26 @@ -5897,6 +5897,60 @@ TPACPI_HANDLE(sfan, ec, "SFAN",  /* 570 */
  27            );                   /* all others */
  28
  29  /*
  30 + * Unitialized HFSP quirk: ACPI DSDT and EC fail to initialize the
  31 + * HFSP register at boot, so it contains 0x07 but the Thinkpad could
  32 + * be in auto mode (0x80).
  33 + *
  34 + * This is corrected by any write to HFSP either by the driver, or
  35 + * by the firmware.
  36 + *
  37 + * We assume 0x07 really means auto mode while this quirk is active,
  38 + * as this is far more likely than the ThinkPad being in level 7,
  39 + * which is only used by the firmware during thermal emergencies.
  40 + */
  41 +
  42 +static void fan_quirk1_detect(void)
  43 +{
  44 +       /* In some ThinkPads, neither the EC nor the ACPI
  45 +        * DSDT initialize the HFSP register, and it ends up
  46 +        * being initially set to 0x07 when it *could* be
  47 +        * either 0x07 or 0x80.
  48 +        *
  49 +        * Enable for TP-1Y (T43), TP-78 (R51e),
  50 +        * TP-76 (R52), TP-70 (T43, R52), which are known
  51 +        * to be buggy. */
  52 +       if (fan_control_initial_status == 0x07) {
  53 +               switch (thinkpad_id.ec_model) {
  54 +               case 0x5931: /* TP-1Y */
  55 +               case 0x3837: /* TP-78 */
  56 +               case 0x3637: /* TP-76 */
  57 +               case 0x3037: /* TP-70 */
  58 +                       printk(TPACPI_NOTICE
  59 +                              "fan_init: initial fan status is unknown, "
  60 +                              "assuming it is in auto mode\n");
  61 +                       tp_features.fan_ctrl_status_undef = 1;
  62 +                       ;;
  63 +               }
  64 +       }
  65 +}
  66 +
  67 +static void fan_quirk1_handle(u8 *fan_status)
  68 +{
  69 +       if (unlikely(tp_features.fan_ctrl_status_undef)) {
  70 +               if (*fan_status != fan_control_initial_status) {
  71 +                       /* something changed the HFSP regisnter since
  72 +                        * driver init time, so it is not undefined
  73 +                        * anymore */
  74 +                       tp_features.fan_ctrl_status_undef = 0;
  75 +               } else {
  76 +                       /* Return most likely status. In fact, it
  77 +                        * might be the only possible status */
  78 +                       *fan_status = TP_EC_FAN_AUTO;
  79 +               }
  80 +       }
  81 +}
  82 +
  83 +/*
  84   * Call with fan_mutex held
  85   */
  86  static void fan_update_desired_level(u8 status)
  87 @@ -5934,8 +5988,10 @@ static int fan_get_status(u8 *status)
  88                 if (unlikely(!acpi_ec_read(fan_status_offset, &s)))
  89                         return -EIO;
  90
  91 -               if (likely(status))
  92 +               if (likely(status)) {
  93                         *status = s;
  94 +                       fan_quirk1_handle(status);
  95 +               }
  96
  97                 break;
  98
  99 @@ -6245,16 +6301,6 @@ static ssize_t fan_pwm1_enable_show(struct device *dev,
 100         if (res)
 101                 return res;
 102
 103 -       if (unlikely(tp_features.fan_ctrl_status_undef)) {
 104 -               if (status != fan_control_initial_status) {
 105 -                       tp_features.fan_ctrl_status_undef = 0;
 106 -               } else {
 107 -                       /* Return most likely status. In fact, it
 108 -                        * might be the only possible status */
 109 -                       status = TP_EC_FAN_AUTO;
 110 -               }
 111 -       }
 112 -
 113         if (status & TP_EC_FAN_FULLSPEED) {
 114                 mode = 0;
 115         } else if (status & TP_EC_FAN_AUTO) {
 116 @@ -6319,14 +6365,6 @@ static ssize_t fan_pwm1_show(struct device *dev,
 117         if (res)
 118                 return res;
 119
 120 -       if (unlikely(tp_features.fan_ctrl_status_undef)) {
 121 -               if (status != fan_control_initial_status) {
 122 -                       tp_features.fan_ctrl_status_undef = 0;
 123 -               } else {
 124 -                       status = TP_EC_FAN_AUTO;
 125 -               }
 126 -       }
 127 -
 128         if ((status &
 129              (TP_EC_FAN_AUTO | TP_EC_FAN_FULLSPEED)) != 0)
 130                 status = fan_control_desired_level;
 131 @@ -6458,29 +6496,7 @@ static int __init fan_init(struct ibm_init_struct *iibm)
 132                 if (likely(acpi_ec_read(fan_status_offset,
 133                                         &fan_control_initial_status))) {
 134                         fan_status_access_mode = TPACPI_FAN_RD_TPEC;
 135 -
 136 -                       /* In some ThinkPads, neither the EC nor the ACPI
 137 -                        * DSDT initialize the fan status, and it ends up
 138 -                        * being set to 0x07 when it *could* be either
 139 -                        * 0x07 or 0x80.
 140 -                        *
 141 -                        * Enable for TP-1Y (T43), TP-78 (R51e),
 142 -                        * TP-76 (R52), TP-70 (T43, R52), which are known
 143 -                        * to be buggy. */
 144 -                       if (fan_control_initial_status == 0x07) {
 145 -                               switch (thinkpad_id.ec_model) {
 146 -                               case 0x5931: /* TP-1Y */
 147 -                               case 0x3837: /* TP-78 */
 148 -                               case 0x3637: /* TP-76 */
 149 -                               case 0x3037: /* TP-70 */
 150 -                                       printk(TPACPI_NOTICE
 151 -                                              "fan_init: initial fan status "
 152 -                                              "is unknown, assuming it is "
 153 -                                              "in auto mode\n");
 154 -                                       tp_features.fan_ctrl_status_undef = 1;
 155 -                                       ;;
 156 -                               }
 157 -                       }
 158 +                       fan_quirk1_detect();
 159                 } else {
 160                         printk(TPACPI_ERR
 161                                "ThinkPad ACPI EC access misbehaving, "
 162 @@ -6669,15 +6685,6 @@ static int fan_read(char *p)
 163                 if (rc < 0)
 164                         return rc;
 165
 166 -               if (unlikely(tp_features.fan_ctrl_status_undef)) {
 167 -                       if (status != fan_control_initial_status)
 168 -                               tp_features.fan_ctrl_status_undef = 0;
 169 -                       else
 170 -                               /* Return most likely status. In fact, it
 171 -                                * might be the only possible status */
 172 -                               status = TP_EC_FAN_AUTO;
 173 -               }
 174 -
 175                 len += sprintf(p + len, "status:\t\t%s\n",
 176                                (status != 0) ? "enabled" : "disabled");
 177
 178 --
 179 1.5.6.5
 180