regulator: Add ramp_delay configuration to constraints

For some hardwares ramp_delay for BUCKs is a configurable parameter which can
be configured through DT or board file.This patch adds ramp_delay to regulator
constraints and allow user to configure it for regulators which supports this
feature, through DT or board file. It will provide two ways of setting the
ramp_delay for a regulator:
	First, by setting it as constraints in board file(for configurable
regulators) and set_machine_constraints() will take care of setting it on
hardware by calling(the provided) .set_ramp_delay() operation(callback).
	Second, by setting it as data in regulator_desc(as fixed/default
ramp_delay rate) for a regulator in driver.

regulator_set_voltage_time_sel() will give preference to
constraints->ramp_delay while reading ramp_delay rate for regulator. Similarly
users should also take care accordingly while refering ramp_delay rate(in case
of implementing their private .set_voltage_time_sel() callbacks for different
regulators).

[Rewrote subject for 80 columns -- broonie]

Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Yadwinder Singh Brar 2012-06-11 17:41:08 +05:30 committed by Mark Brown
parent b5fb77e018
commit 6f0b2c696c
5 changed files with 31 additions and 5 deletions

View file

@ -10,6 +10,7 @@ Optional properties:
- regulator-always-on: boolean, regulator should never be disabled
- regulator-boot-on: bootloader/firmware enabled regulator
- <name>-supply: phandle to the parent supply/regulator node
- regulator-ramp-delay: ramp delay for regulator(in mV/uS)
Example:

View file

@ -967,6 +967,14 @@ static int set_machine_constraints(struct regulator_dev *rdev,
}
}
if (rdev->constraints->ramp_delay && ops->set_ramp_delay) {
ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
if (ret < 0) {
rdev_err(rdev, "failed to set ramp_delay\n");
goto out;
}
}
print_constraints(rdev);
return 0;
out:
@ -2296,10 +2304,17 @@ int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
unsigned int old_selector,
unsigned int new_selector)
{
if (rdev->desc->ramp_delay && rdev->desc->uV_step)
return DIV_ROUND_UP(rdev->desc->uV_step *
abs(new_selector - old_selector),
rdev->desc->ramp_delay * 1000);
if (rdev->desc->uV_step) {
if (rdev->constraints->ramp_delay)
return DIV_ROUND_UP(rdev->desc->uV_step *
abs(new_selector - old_selector),
rdev->constraints->ramp_delay * 1000);
if (rdev->desc->ramp_delay)
return DIV_ROUND_UP(rdev->desc->uV_step *
abs(new_selector - old_selector),
rdev->desc->ramp_delay * 1000);
rdev_warn(rdev, "ramp_delay not set\n");
}
return 0;
}

View file

@ -20,7 +20,7 @@ static void of_get_regulation_constraints(struct device_node *np,
struct regulator_init_data **init_data)
{
const __be32 *min_uV, *max_uV, *uV_offset;
const __be32 *min_uA, *max_uA;
const __be32 *min_uA, *max_uA, *ramp_delay;
struct regulation_constraints *constraints = &(*init_data)->constraints;
constraints->name = of_get_property(np, "regulator-name", NULL);
@ -60,6 +60,10 @@ static void of_get_regulation_constraints(struct device_node *np,
constraints->always_on = true;
else /* status change should be possible if not always on. */
constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
ramp_delay = of_get_property(np, "regulator-ramp-delay", NULL);
if (ramp_delay)
constraints->min_uV = be32_to_cpu(*ramp_delay);
}
/**

View file

@ -67,6 +67,8 @@ enum regulator_status {
*
* @enable_time: Time taken for the regulator voltage output voltage to
* stabilise after being enabled, in microseconds.
* @set_ramp_delay: Set the ramp delay for the regulator. The driver should
* select ramp delay equal to or less than(closest) ramp_delay.
* @set_voltage_time_sel: Time taken for the regulator voltage output voltage
* to stabilise after being set to a new value, in microseconds.
* The function provides the from and to voltage selector, the
@ -113,6 +115,7 @@ struct regulator_ops {
/* Time taken to enable or set voltage on the regulator */
int (*enable_time) (struct regulator_dev *);
int (*set_ramp_delay) (struct regulator_dev *, int ramp_delay);
int (*set_voltage_time_sel) (struct regulator_dev *,
unsigned int old_selector,
unsigned int new_selector);

View file

@ -92,6 +92,7 @@ struct regulator_state {
* mode.
* @initial_state: Suspend state to set by default.
* @initial_mode: Mode to set at startup.
* @ramp_delay: Time to settle down after voltage change (unit: mV/us)
*/
struct regulation_constraints {
@ -125,6 +126,8 @@ struct regulation_constraints {
/* mode to set on startup */
unsigned int initial_mode;
unsigned int ramp_delay;
/* constraint flags */
unsigned always_on:1; /* regulator never off when system is on */
unsigned boot_on:1; /* bootloader/firmware enabled regulator */