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ARM: OMAP2+: voltage: ensure voltage used is exact voltage from OPP table 

When using the SMPS regulators to scale voltages, the regulator
framework may pass a minimum voltage that is not an exact OPP voltage.
For the VC/VP controlled voltage domains, we must ensure that the
voltage requested is the exact voltage from the OPP table.  This is
especially critical when using SR.

To fix, voltdm_scale() uses the target voltage passed to walk through
the OPP voltages until it finds a voltage that is >= one of the OPP
voltages.

Cc: Tero Kristo <t-kristo@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
This commit is contained in:
Kevin Hilman 2012-03-02 14:08:57 -08:00
parent e160dda0f4
commit c15f1d84bb
1 changed files with 18 additions and 3 deletions
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21
arch/arm/mach-omap2/voltage.c
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@ -73,7 +73,8 @@ unsigned long voltdm_get_voltage(struct voltagedomain *voltdm)
int voltdm_scale(struct voltagedomain *voltdm,
unsigned long target_volt)
{
int ret;
int ret, i;
unsigned long volt = 0;
if (!voltdm || IS_ERR(voltdm)) {
pr_warning("%s: VDD specified does not exist!\n", __func__);
@ -86,9 +87,23 @@ int voltdm_scale(struct voltagedomain *voltdm,
return -ENODATA;
}
ret = voltdm->scale(voltdm, target_volt);
/* Adjust voltage to the exact voltage from the OPP table */
for (i = 0; voltdm->volt_data[i].volt_nominal != 0; i++) {
if (voltdm->volt_data[i].volt_nominal >= target_volt) {
volt = voltdm->volt_data[i].volt_nominal;
break;
}
}
if (!volt) {
pr_warning("%s: not scaling. OPP voltage for %lu, not found.\n",
__func__, target_volt);
return -EINVAL;
}
ret = voltdm->scale(voltdm, volt);
if (!ret)
voltdm->nominal_volt = target_volt;
voltdm->nominal_volt = volt;
return ret;
}