regulator: core: Add REGULATOR_EVENT_PRE_VOLTAGE_CHANGE (and ABORT)
In some cases we need to know when a regulator is about to be changed.
Add a way for clients to be notified. Note that for set_voltage() we
don't necessarily know what voltage we'll end up with, so we tell the
client what the range will be so they can prepare.
Signed-off-by: Heiko Stübner <heiko@sntech.de>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Mark Brown <broonie+linaro@kernel.org>
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index a3c3785..dabc8e8 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -102,7 +102,7 @@
static int _regulator_get_voltage(struct regulator_dev *rdev);
static int _regulator_get_current_limit(struct regulator_dev *rdev);
static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
-static void _notifier_call_chain(struct regulator_dev *rdev,
+static int _notifier_call_chain(struct regulator_dev *rdev,
unsigned long event, void *data);
static int _regulator_do_set_voltage(struct regulator_dev *rdev,
int min_uV, int max_uV);
@@ -2369,6 +2369,55 @@
}
EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
+static int _regulator_call_set_voltage(struct regulator_dev *rdev,
+ int min_uV, int max_uV,
+ unsigned *selector)
+{
+ struct pre_voltage_change_data data;
+ int ret;
+
+ data.old_uV = _regulator_get_voltage(rdev);
+ data.min_uV = min_uV;
+ data.max_uV = max_uV;
+ ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
+ &data);
+ if (ret & NOTIFY_STOP_MASK)
+ return -EINVAL;
+
+ ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
+ if (ret >= 0)
+ return ret;
+
+ _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
+ (void *)data.old_uV);
+
+ return ret;
+}
+
+static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
+ int uV, unsigned selector)
+{
+ struct pre_voltage_change_data data;
+ int ret;
+
+ data.old_uV = _regulator_get_voltage(rdev);
+ data.min_uV = uV;
+ data.max_uV = uV;
+ ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
+ &data);
+ if (ret & NOTIFY_STOP_MASK)
+ return -EINVAL;
+
+ ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
+ if (ret >= 0)
+ return ret;
+
+ _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
+ (void *)data.old_uV);
+
+ return ret;
+}
+
static int _regulator_do_set_voltage(struct regulator_dev *rdev,
int min_uV, int max_uV)
{
@@ -2396,8 +2445,8 @@
}
if (rdev->desc->ops->set_voltage) {
- ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV,
- &selector);
+ ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
+ &selector);
if (ret >= 0) {
if (rdev->desc->ops->list_voltage)
@@ -2432,8 +2481,8 @@
if (old_selector == selector)
ret = 0;
else
- ret = rdev->desc->ops->set_voltage_sel(
- rdev, ret);
+ ret = _regulator_call_set_voltage_sel(
+ rdev, best_val, selector);
} else {
ret = -EINVAL;
}
@@ -3079,11 +3128,11 @@
/* notify regulator consumers and downstream regulator consumers.
* Note mutex must be held by caller.
*/
-static void _notifier_call_chain(struct regulator_dev *rdev,
+static int _notifier_call_chain(struct regulator_dev *rdev,
unsigned long event, void *data)
{
/* call rdev chain first */
- blocking_notifier_call_chain(&rdev->notifier, event, data);
+ return blocking_notifier_call_chain(&rdev->notifier, event, data);
}
/**