releases/3.0.23/hwmon-max6639-fix-fan_from_reg-calculation.patch

   1 From b63d97a36edb1aecf8c13e5f5783feff4d64c24b Mon Sep 17 00:00:00 2001
   2 From: Chris D Schimp <silverchris@gmail.com>
   3 Date: Mon, 20 Feb 2012 16:59:24 -0500
   4 Subject: hwmon: (max6639) Fix FAN_FROM_REG calculation
   5
   6 From: Chris D Schimp <silverchris@gmail.com>
   7
   8 commit b63d97a36edb1aecf8c13e5f5783feff4d64c24b upstream.
   9
  10 RPM calculation from tachometer value does not depend on PPR.
  11 Also, do not report negative RPM values.
  12
  13 Signed-off-by: Chris D Schimp <silverchris@gmail.com>
  14 [guenter.roeck@ericsson.com: do not report negative RPM values]
  15 Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
  16 Acked-by: Roland Stigge <stigge@antcom.de>
  17 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  18
  19 ---
  20  drivers/hwmon/max6639.c |    6 +++---
  21  1 file changed, 3 insertions(+), 3 deletions(-)
  22
  23 --- a/drivers/hwmon/max6639.c
  24 +++ b/drivers/hwmon/max6639.c
  25 @@ -72,8 +72,8 @@ static unsigned short normal_i2c[] = { 0
  26
  27  static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 };
  28
  29 -#define FAN_FROM_REG(val, div, rpm_range)      ((val) == 0 ? -1 : \
  30 -       (val) == 255 ? 0 : (rpm_ranges[rpm_range] * 30) / ((div + 1) * (val)))
  31 +#define FAN_FROM_REG(val, rpm_range)   ((val) == 0 || (val) == 255 ? \
  32 +                               0 : (rpm_ranges[rpm_range] * 30) / (val))
  33  #define TEMP_LIMIT_TO_REG(val) SENSORS_LIMIT((val) / 1000, 0, 255)
  34
  35  /*
  36 @@ -333,7 +333,7 @@ static ssize_t show_fan_input(struct dev
  37                 return PTR_ERR(data);
  38
  39         return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
  40 -                      data->ppr, data->rpm_range));
  41 +                      data->rpm_range));
  42  }
  43
  44  static ssize_t show_alarm(struct device *dev,