OMAP3+: VP/VC: ensure vp errgen is configured for the right OPP

Since target_volt converted by omap_voltage_get_voltdata to get to
vp_errgain for the OPP voltage level, we can have a scenario as follows:
OPP100 Vnom=1.2V, Vcalib = 0V(not calibrated) vp_errgain=0x16
OPPNitro Vnom=1.375, Vcalib = 1.2V vp_errgain=0x27
When a request to vc_bypass or vp_forceupdate is provided to OPPNitro
volt_data pointer, it in turn calls vc_prescale with 1.2V, this gets
passed down to vp_errgen_configure, who converts it back into vdata
using omap_voltage_get_voltdata

However, omap_voltage_get_voltdata walks through the volt_data array
and finds the first match of OPP100 where Vnom = 1.2V and returns
the volt_data pointer for OPP100, this causes 0x16 to be selected
for VP errgain instead of 0x27, causing instability for voltage scale
operation.

Instead, pass the volt_data pointer straight to vc_prescale and down
to vp_errgen_configure to ensure that the right configuration parameters
are used.

Change-Id: I96c697175fb5d16c53de9891ec5c008101c0550b
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>

1 files changed, 6 insertions, 9 deletions

diff --git a/arch/arm/mach-omap2/vp.c b/arch/arm/mach-omap2/vp.c
index b5c3524..3f16be5 100644
--- a/arch/arm/mach-omap2/vp.c
+++ b/arch/arm/mach-omap2/vp.c
@@ -136,15 +136,11 @@ void omap_vp_clear_transdone(struct voltagedomain *voltdm)
 }
 
 int omap_vp_update_errorgain(struct voltagedomain *voltdm,
-			     unsigned long target_volt)
+			     struct omap_volt_data *volt_data)
 {
-	struct omap_volt_data *volt_data;
-
-	/* Get volt_data corresponding to target_volt */
-	volt_data = omap_voltage_get_voltdata(voltdm, target_volt);
-	if (IS_ERR(volt_data)) {
-		pr_err("%s: vdm %s no voltage data for %ld\n", __func__,
-			voltdm->name, target_volt);
+	if (IS_ERR_OR_NULL(volt_data)) {
+		pr_err("%s: vdm %s bad voltage data %p\n", __func__,
+			voltdm->name, volt_data);
 		return -EINVAL;
 	}
 
@@ -203,7 +199,8 @@ int omap_vp_forceupdate_scale(struct voltagedomain *voltdm,
 			"%s:vdd_%s idletimdout forceupdate(v=%ld)\n",
 			__func__, voltdm->name, target_volt);
 
-	ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, &current_vsel);
+	ret = omap_vc_pre_scale(voltdm, target_volt, target_v,
+				&target_vsel, &current_vsel);
 	if (ret)
 		return ret;