regulator: add set_voltage_time_sel infrastructure
This makes it possible to set the stabilization time for voltage
regulators in the same manner as enable_time(). The interface
only supports regulators that implements fixed selectors.
Cc: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index e611f67..e7e4460 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1629,6 +1629,7 @@
int min_uV, int max_uV)
{
int ret;
+ int delay = 0;
unsigned int selector;
trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
@@ -1662,6 +1663,22 @@
}
}
+ /*
+ * If we can't obtain the old selector there is not enough
+ * info to call set_voltage_time_sel().
+ */
+ if (rdev->desc->ops->set_voltage_time_sel &&
+ rdev->desc->ops->get_voltage_sel) {
+ unsigned int old_selector = 0;
+
+ ret = rdev->desc->ops->get_voltage_sel(rdev);
+ if (ret < 0)
+ return ret;
+ old_selector = ret;
+ delay = rdev->desc->ops->set_voltage_time_sel(rdev,
+ old_selector, selector);
+ }
+
if (best_val != INT_MAX) {
ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
selector = best_val;
@@ -1672,6 +1689,14 @@
ret = -EINVAL;
}
+ /* Insert any necessary delays */
+ if (delay >= 1000) {
+ mdelay(delay / 1000);
+ udelay(delay % 1000);
+ } else if (delay) {
+ udelay(delay);
+ }
+
if (ret == 0)
_notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
NULL);
diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h
index b8ed16a..6c433b8 100644
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -63,7 +63,11 @@
* when running with the specified parameters.
*
* @enable_time: Time taken for the regulator voltage output voltage to
- * stabalise after being enabled, in microseconds.
+ * stabilise after being enabled, in microseconds.
+ * @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
+ * function should return the worst case.
*
* @set_suspend_voltage: Set the voltage for the regulator when the system
* is suspended.
@@ -103,8 +107,11 @@
int (*set_mode) (struct regulator_dev *, unsigned int mode);
unsigned int (*get_mode) (struct regulator_dev *);
- /* Time taken to enable the regulator */
+ /* Time taken to enable or set voltage on the regulator */
int (*enable_time) (struct regulator_dev *);
+ int (*set_voltage_time_sel) (struct regulator_dev *,
+ unsigned int old_selector,
+ unsigned int new_selector);
/* report regulator status ... most other accessors report
* control inputs, this reports results of combining inputs