[PATCH 3/5] intel_pstate: fix pid_reset to use fixed point values

From: dirk . brandewie
Date: Wed Feb 12 2014 - 13:02:18 EST


From: Dirk Brandewie <dirk.j.brandewie@xxxxxxxxx>

commit d253d2a526 Improve accuracy by not truncating until final
result, changed internal variables of the PID to be fixed point
numbers. Update the pid_reset() to reflect this change.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@xxxxxxxxx>
---
drivers/cpufreq/intel_pstate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index d692b10..b80c03d 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -150,7 +150,7 @@ static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
pid->setpoint = setpoint;
pid->deadband = deadband;
pid->integral = int_tofp(integral);
- pid->last_err = setpoint - busy;
+ pid->last_err = int_tofp(setpoint) - int_tofp(busy);
}

static inline void pid_p_gain_set(struct _pid *pid, int percent)
--
1.8.3.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/