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cpufreq: OMAP: specify range for voltage scaling

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Specify voltage in ranges for regulator. Range
used is tolerance specified for OPP.

This helps to achieve DVFS with a wider range of
regulators.

Cc: Kevin Hilman <khilman@ti.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Afzal Mohammed <afzal@ti.com>
This commit is contained in:
Afzal Mohammed 2012-02-23 19:19:24 +05:30 committed by Kevin Hilman
parent 53dfe8a884
commit 42daffd2d6
1 changed files with 7 additions and 3 deletions
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10
drivers/cpufreq/omap-cpufreq.c
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@ -38,6 +38,9 @@
#include <mach/hardware.h>
/* OPP tolerance in percentage */
#define OPP_TOLERANCE 4
#ifdef CONFIG_SMP
struct lpj_info {
unsigned long ref;
@ -81,7 +84,7 @@ static int omap_target(struct cpufreq_policy *policy,
int r, ret = 0;
struct cpufreq_freqs freqs;
struct opp *opp;
unsigned long freq, volt = 0, volt_old = 0;
unsigned long freq, volt = 0, volt_old = 0, tol = 0;
if (!freq_table) {
dev_err(mpu_dev, "%s: cpu%d: no freq table!\n", __func__,
@ -125,6 +128,7 @@ static int omap_target(struct cpufreq_policy *policy,
return -EINVAL;
}
volt = opp_get_voltage(opp);
tol = volt * OPP_TOLERANCE / 100;
volt_old = regulator_get_voltage(mpu_reg);
}
@ -134,7 +138,7 @@ static int omap_target(struct cpufreq_policy *policy,
/* scaling up? scale voltage before frequency */
if (mpu_reg && (freqs.new > freqs.old)) {
r = regulator_set_voltage(mpu_reg, volt, volt);
r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol);
if (r < 0) {
dev_warn(mpu_dev, "%s: unable to scale voltage up.\n",
__func__);
@ -147,7 +151,7 @@ static int omap_target(struct cpufreq_policy *policy,
/* scaling down? scale voltage after frequency */
if (mpu_reg && (freqs.new < freqs.old)) {
r = regulator_set_voltage(mpu_reg, volt, volt);
r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol);
if (r < 0) {
dev_warn(mpu_dev, "%s: unable to scale voltage down.\n",
__func__);