Unverified Commit 42d7c87b authored by Kory Maincent's avatar Kory Maincent Committed by Mark Brown
Browse files

regulator: Add support for power budget 



Introduce power budget management for the regulator device. Enable tracking
of available power capacity by providing helpers to request and release
power budget allocations.

Signed-off-by: default avatarKory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20250115-feature_regulator_pw_budget-v2-1-0a44b949e6bc@bootlin.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent c3ad22ad

drivers/regulator/core.c

+114 −0
Original line number Diff line number Diff line
@@ -917,6 +917,26 @@ static ssize_t bypass_show(struct device *dev, 
}

static DEVICE_ATTR_RO(bypass);



static ssize_t power_budget_milliwatt_show(struct device *dev,

					   struct device_attribute *attr,

					   char *buf)

{

	struct regulator_dev *rdev = dev_get_drvdata(dev);



	return sprintf(buf, "%d\n", rdev->constraints->pw_budget_mW);

}

static DEVICE_ATTR_RO(power_budget_milliwatt);



static ssize_t power_requested_milliwatt_show(struct device *dev,

					      struct device_attribute *attr,

					      char *buf)

{

	struct regulator_dev *rdev = dev_get_drvdata(dev);



	return sprintf(buf, "%d\n", rdev->pw_requested_mW);

}

static DEVICE_ATTR_RO(power_requested_milliwatt);



#define REGULATOR_ERROR_ATTR(name, bit)							\

	static ssize_t name##_show(struct device *dev, struct device_attribute *attr,	\

				   char *buf)						\
@@ -1149,6 +1169,10 @@ static void print_constraints_debug(struct regulator_dev *rdev) 
	if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)

		count += scnprintf(buf + count, len - count, "standby ");



	if (constraints->pw_budget_mW)

		count += scnprintf(buf + count, len - count, "%d mW budget",

				   constraints->pw_budget_mW);



	if (!count)

		count = scnprintf(buf, len, "no parameters");

	else
@@ -1627,6 +1651,9 @@ static int set_machine_constraints(struct regulator_dev *rdev) 
		rdev->last_off = ktime_get();

	}



	if (!rdev->constraints->pw_budget_mW)

		rdev->constraints->pw_budget_mW = INT_MAX;



	print_constraints(rdev);

	return 0;

}
@@ -4601,6 +4628,87 @@ int regulator_get_current_limit(struct regulator *regulator) 
}

EXPORT_SYMBOL_GPL(regulator_get_current_limit);



/**

 * regulator_get_unclaimed_power_budget - get regulator unclaimed power budget

 * @regulator: regulator source

 *

 * Return: Unclaimed power budget of the regulator in mW.

 */

int regulator_get_unclaimed_power_budget(struct regulator *regulator)

{

	return regulator->rdev->constraints->pw_budget_mW -

	       regulator->rdev->pw_requested_mW;

}

EXPORT_SYMBOL_GPL(regulator_get_unclaimed_power_budget);



/**

 * regulator_request_power_budget - request power budget on a regulator

 * @regulator: regulator source

 * @pw_req: Power requested

 *

 * Return: 0 on success or a negative error number on failure.

 */

int regulator_request_power_budget(struct regulator *regulator,

				   unsigned int pw_req)

{

	struct regulator_dev *rdev = regulator->rdev;

	int ret = 0, pw_tot_req;



	regulator_lock(rdev);

	if (rdev->supply) {

		ret = regulator_request_power_budget(rdev->supply, pw_req);

		if (ret < 0)

			goto out;

	}



	pw_tot_req = rdev->pw_requested_mW + pw_req;

	if (pw_tot_req > rdev->constraints->pw_budget_mW) {

		rdev_warn(rdev, "power requested %d mW out of budget %d mW",

			  pw_req,

			  rdev->constraints->pw_budget_mW - rdev->pw_requested_mW);

		regulator_notifier_call_chain(rdev,

					      REGULATOR_EVENT_OVER_CURRENT_WARN,

					      NULL);

		ret = -ERANGE;

		goto out;

	}



	rdev->pw_requested_mW = pw_tot_req;

out:

	regulator_unlock(rdev);

	return ret;

}

EXPORT_SYMBOL_GPL(regulator_request_power_budget);



/**

 * regulator_free_power_budget - free power budget on a regulator

 * @regulator: regulator source

 * @pw: Power to be released.

 *

 * Return: Power budget of the regulator in mW.

 */

void regulator_free_power_budget(struct regulator *regulator,

				 unsigned int pw)

{

	struct regulator_dev *rdev = regulator->rdev;

	int pw_tot_req;



	regulator_lock(rdev);

	if (rdev->supply)

		regulator_free_power_budget(rdev->supply, pw);



	pw_tot_req = rdev->pw_requested_mW - pw;

	if (pw_tot_req >= 0)

		rdev->pw_requested_mW = pw_tot_req;

	else

		rdev_warn(rdev,

			  "too much power freed %d mW (already requested %d mW)",

			  pw, rdev->pw_requested_mW);



	regulator_unlock(rdev);

}

EXPORT_SYMBOL_GPL(regulator_free_power_budget);



/**

 * regulator_set_mode - set regulator operating mode

 * @regulator: regulator source
@@ -5239,6 +5347,8 @@ static struct attribute *regulator_dev_attrs[] = { 
	&dev_attr_suspend_standby_mode.attr,

	&dev_attr_suspend_mem_mode.attr,

	&dev_attr_suspend_disk_mode.attr,

	&dev_attr_power_budget_milliwatt.attr,

	&dev_attr_power_requested_milliwatt.attr,

	NULL

};
@@ -5320,6 +5430,10 @@ static umode_t regulator_attr_is_visible(struct kobject *kobj, 
	    attr == &dev_attr_suspend_disk_mode.attr)

		return ops->set_suspend_mode ? mode : 0;



	if (attr == &dev_attr_power_budget_milliwatt.attr ||

	    attr == &dev_attr_power_requested_milliwatt.attr)

		return rdev->constraints->pw_budget_mW != INT_MAX ? mode : 0;



	return mode;

}

drivers/regulator/of_regulator.c

+3 −0
Original line number Diff line number Diff line
@@ -125,6 +125,9 @@ static int of_get_regulation_constraints(struct device *dev, 
	if (constraints->min_uA != constraints->max_uA)

		constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;



	if (!of_property_read_u32(np, "regulator-power-budget-milliwatt", &pval))

		constraints->pw_budget_mW = pval;



	constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");

	constraints->always_on = of_property_read_bool(np, "regulator-always-on");

	if (!constraints->always_on) /* status change should be possible. */

include/linux/regulator/consumer.h

+21 −0
Original line number Diff line number Diff line
@@ -258,6 +258,11 @@ int regulator_sync_voltage(struct regulator *regulator); 
int regulator_set_current_limit(struct regulator *regulator,

			       int min_uA, int max_uA);

int regulator_get_current_limit(struct regulator *regulator);

int regulator_get_unclaimed_power_budget(struct regulator *regulator);

int regulator_request_power_budget(struct regulator *regulator,

				   unsigned int pw_req);

void regulator_free_power_budget(struct regulator *regulator,

				 unsigned int pw);



int regulator_set_mode(struct regulator *regulator, unsigned int mode);

unsigned int regulator_get_mode(struct regulator *regulator);
@@ -571,6 +576,22 @@ static inline int regulator_get_current_limit(struct regulator *regulator) 
	return 0;

}



static inline int regulator_get_unclaimed_power_budget(struct regulator *regulator)

{

	return INT_MAX;

}



static inline int regulator_request_power_budget(struct regulator *regulator,

						 unsigned int pw_req)

{

	return -EOPNOTSUPP;

}



static inline void regulator_free_power_budget(struct regulator *regulator,

					       unsigned int pw)

{

}



static inline int regulator_set_mode(struct regulator *regulator,

	unsigned int mode)

{

include/linux/regulator/driver.h

+2 −0
Original line number Diff line number Diff line
@@ -656,6 +656,8 @@ struct regulator_dev { 
	int cached_err;

	bool use_cached_err;

	spinlock_t err_lock;



	int pw_requested_mW;

};



/*

include/linux/regulator/machine.h

+2 −0
Original line number Diff line number Diff line
@@ -113,6 +113,7 @@ struct notification_limit { 
 * @min_uA: Smallest current consumers may set.

 * @max_uA: Largest current consumers may set.

 * @ilim_uA: Maximum input current.

 * @pw_budget_mW: Power budget for the regulator in mW.

 * @system_load: Load that isn't captured by any consumer requests.

 *

 * @over_curr_limits:		Limits for acting on over current.
@@ -185,6 +186,7 @@ struct regulation_constraints { 
	int max_uA;

	int ilim_uA;



	int pw_budget_mW;

	int system_load;



	/* used for coupled regulators */