regulator: core: Limit propagation of parent voltage count and list

[ Upstream commit fd086045559d90cd7854818b4c60a7119eda6231 ]

Commit 26988efe11b1 ("regulator: core: Allow to get voltage count and
list from parent") introduces the propagation of the parent voltage
count and list for regulators that don't provide this information
themselves. The goal is to support simple switch regulators, however as
a side effect normal continuous regulators can leak details of their
supplies and provide consumers with inconsistent information.

Limit the propagation of the voltage count and list to switch
regulators.

Fixes: 26988efe11b1 ("regulator: core: Allow to get voltage count and
  list from parent")
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 9403245503dec4aa65fd34b5a576f2f1b764983d..178fcda12cec58ebf47a5855d9bfc1f697d4d63e 100644 (file)
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -2465,7 +2465,7 @@ static int _regulator_list_voltage(struct regulator *regulator,
                ret = ops->list_voltage(rdev, selector);
                if (lock)
                        mutex_unlock(&rdev->mutex);
-       } else if (rdev->supply) {
+       } else if (rdev->is_switch && rdev->supply) {
                ret = _regulator_list_voltage(rdev->supply, selector, lock);
        } else {
                return -EINVAL;
@@ -2523,7 +2523,7 @@ int regulator_count_voltages(struct regulator *regulator)
        if (rdev->desc->n_voltages)
                return rdev->desc->n_voltages;
 
-       if (!rdev->supply)
+       if (!rdev->is_switch || !rdev->supply)
                return -EINVAL;
 
        return regulator_count_voltages(rdev->supply);
@@ -4049,6 +4049,11 @@ regulator_register(const struct regulator_desc *regulator_desc,
                mutex_unlock(&regulator_list_mutex);
        }
 
+       if (!rdev->desc->ops->get_voltage &&
+           !rdev->desc->ops->list_voltage &&
+           !rdev->desc->fixed_uV)
+               rdev->is_switch = true;
+
        ret = device_register(&rdev->dev);
        if (ret != 0) {
                put_device(&rdev->dev);

diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h
index 37b5324105287d927f2f41c27693b8ca54207cf9..3c3786df044cce8f42f161ea378f37392dde75fe 100644 (file)
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -425,6 +425,8 @@ struct regulator_dev {
        struct regulator_enable_gpio *ena_pin;
        unsigned int ena_gpio_state:1;
 
+       unsigned int is_switch:1;
+
        /* time when this regulator was disabled last time */
        unsigned long last_off_jiffy;
 };