msm: krait-regulator: Switch to PFM mode under light load
The pmic gang can operate in low power mode when configured
in PFM mode. In PFM mode the number of phases drop to one
where the gang leader provides all the current.
Use this facility when the combined load decreases below
500mA.
Change-Id: I7e975f811cf1f7cf38300d6c92fd3234d9d0b13f
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
diff --git a/arch/arm/mach-msm/krait-regulator.c b/arch/arm/mach-msm/krait-regulator.c
index 649f7cd..aa9b344 100644
--- a/arch/arm/mach-msm/krait-regulator.c
+++ b/arch/arm/mach-msm/krait-regulator.c
@@ -141,6 +141,7 @@
int pmic_phase_count;
struct list_head krait_power_vregs;
struct mutex krait_power_vregs_lock;
+ bool pfm_mode;
};
static struct pmic_gang_vreg *the_gang;
@@ -542,6 +543,9 @@
return rc;
}
+#define PMIC_FTS_MODE_PFM 0x00
+#define PMIC_FTS_MODE_PWM 0x80
+#define PFM_LOAD_UA 500000
static unsigned int krait_power_get_optimum_mode(struct regulator_dev *rdev,
int input_uV, int output_uV, int load_uA)
{
@@ -553,10 +557,40 @@
mutex_lock(&pvreg->krait_power_vregs_lock);
+ reg_mode = kvreg->mode;
+
kvreg->load_uA = load_uA;
load_total_uA = get_total_load(kvreg);
+ if (load_total_uA < PFM_LOAD_UA) {
+ if (!pvreg->pfm_mode) {
+ rc = msm_spm_enable_fts_lpm(PMIC_FTS_MODE_PFM);
+ if (rc) {
+ dev_err(&rdev->dev,
+ "%s enter PFM failed load %d rc = %d\n",
+ kvreg->name, load_total_uA, rc);
+ goto out;
+ } else {
+ pvreg->pfm_mode = true;
+ }
+ }
+ mutex_unlock(&pvreg->krait_power_vregs_lock);
+ return reg_mode;
+ }
+
+ if (pvreg->pfm_mode) {
+ rc = msm_spm_enable_fts_lpm(PMIC_FTS_MODE_PWM);
+ if (rc) {
+ dev_err(&rdev->dev,
+ "%s exit PFM failed load %d rc = %d\n",
+ kvreg->name, load_total_uA, rc);
+ goto out;
+ } else {
+ pvreg->pfm_mode = false;
+ }
+ }
+
rc = pmic_gang_set_phases(kvreg, load_total_uA);
if (rc < 0) {
dev_err(&rdev->dev, "%s failed set mode %d rc = %d\n",
@@ -564,7 +598,6 @@
goto out;
}
- reg_mode = kvreg->mode;
out:
mutex_unlock(&pvreg->krait_power_vregs_lock);
return reg_mode;