[PATCH v4 2/4] OPP: Add "opp-microwatt" supporting code

From: Lukasz Luba
Date: Tue Mar 01 2022 - 04:36:16 EST


Add new property to the OPP: power value. The OPP entry in the DT can have
"opp-microwatt". Add the needed code to handle this new property in the
existing infrastructure.

Signed-off-by: Lukasz Luba <lukasz.luba@xxxxxxx>
---
drivers/opp/core.c | 25 ++++++++++++++++++++++
drivers/opp/debugfs.c | 3 +++
drivers/opp/of.c | 47 ++++++++++++++++++++++++++++++++++++++++--
include/linux/pm_opp.h | 12 ++++++++++-
4 files changed, 84 insertions(+), 3 deletions(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 3057beabd370..740407252298 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -113,6 +113,31 @@ unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
}
EXPORT_SYMBOL_GPL(dev_pm_opp_get_voltage);

+/**
+ * dev_pm_opp_get_power() - Gets the power corresponding to an opp
+ * @opp: opp for which power has to be returned for
+ *
+ * Return: power in micro watt corresponding to the opp, else
+ * return 0
+ *
+ * This is useful only for devices with single power supply.
+ */
+unsigned long dev_pm_opp_get_power(struct dev_pm_opp *opp)
+{
+ unsigned long opp_power = 0;
+ int i;
+
+ if (IS_ERR_OR_NULL(opp)) {
+ pr_err("%s: Invalid parameters\n", __func__);
+ return 0;
+ }
+ for (i = 0; i < opp->opp_table->regulator_count; i++)
+ opp_power += opp->supplies[i].u_watt;
+
+ return opp_power;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_power);
+
/**
* dev_pm_opp_get_freq() - Gets the frequency corresponding to an available opp
* @opp: opp for which frequency has to be returned for
diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
index 596c185b5dda..45837f3c1765 100644
--- a/drivers/opp/debugfs.c
+++ b/drivers/opp/debugfs.c
@@ -99,6 +99,9 @@ static void opp_debug_create_supplies(struct dev_pm_opp *opp,

debugfs_create_ulong("u_amp", S_IRUGO, d,
&opp->supplies[i].u_amp);
+
+ debugfs_create_ulong("u_watt", S_IRUGO, d,
+ &opp->supplies[i].u_watt);
}
}

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index 2f40afa4e65c..7bff30f27dc1 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -575,8 +575,9 @@ static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
struct opp_table *opp_table)
{
- u32 *microvolt, *microamp = NULL;
- int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
+ u32 *microvolt, *microamp = NULL, *microwatt = NULL;
+ int supplies = opp_table->regulator_count;
+ int vcount, icount, pcount, ret, i, j;
struct property *prop = NULL;
char name[NAME_MAX];

@@ -688,6 +689,43 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
}
}

+ /* Search for "opp-microwatt" */
+ sprintf(name, "opp-microwatt");
+ prop = of_find_property(opp->np, name, NULL);
+
+ if (prop) {
+ pcount = of_property_count_u32_elems(opp->np, name);
+ if (pcount < 0) {
+ dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
+ name, pcount);
+ ret = pcount;
+ goto free_microamp;
+ }
+
+ if (pcount != supplies) {
+ dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
+ __func__, name, pcount, supplies);
+ ret = -EINVAL;
+ goto free_microamp;
+ }
+
+ microwatt = kmalloc_array(pcount, sizeof(*microwatt),
+ GFP_KERNEL);
+ if (!microwatt) {
+ ret = -EINVAL;
+ goto free_microamp;
+ }
+
+ ret = of_property_read_u32_array(opp->np, name, microwatt,
+ pcount);
+ if (ret) {
+ dev_err(dev, "%s: error parsing %s: %d\n", __func__,
+ name, ret);
+ ret = -EINVAL;
+ goto free_microwatt;
+ }
+ }
+
for (i = 0, j = 0; i < supplies; i++) {
opp->supplies[i].u_volt = microvolt[j++];

@@ -701,8 +739,13 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,

if (microamp)
opp->supplies[i].u_amp = microamp[i];
+
+ if (microwatt)
+ opp->supplies[i].u_watt = microwatt[i];
}

+free_microwatt:
+ kfree(microwatt);
free_microamp:
kfree(microamp);
free_microvolt:
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 879c138c7b8e..0d85a63a1f78 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -32,14 +32,17 @@ enum dev_pm_opp_event {
* @u_volt_min: Minimum voltage in microvolts corresponding to this OPP
* @u_volt_max: Maximum voltage in microvolts corresponding to this OPP
* @u_amp: Maximum current drawn by the device in microamperes
+ * @u_watt: Power used by the device in microwatts
*
- * This structure stores the voltage/current values for a single power supply.
+ * This structure stores the voltage/current/power values for a single power
+ * supply.
*/
struct dev_pm_opp_supply {
unsigned long u_volt;
unsigned long u_volt_min;
unsigned long u_volt_max;
unsigned long u_amp;
+ unsigned long u_watt;
};

/**
@@ -94,6 +97,8 @@ void dev_pm_opp_put_opp_table(struct opp_table *opp_table);

unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp);

+unsigned long dev_pm_opp_get_power(struct dev_pm_opp *opp);
+
unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp);

unsigned int dev_pm_opp_get_level(struct dev_pm_opp *opp);
@@ -186,6 +191,11 @@ static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
return 0;
}

+static inline unsigned long dev_pm_opp_get_power(struct dev_pm_opp *opp)
+{
+ return 0;
+}
+
static inline unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp)
{
return 0;
--
2.17.1