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

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>

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index c20b28a63d15ad24cd90e8c3f818865f1d8e772f..aff302dfab5de34e92d1a16320ada8f1f9a7330b 100644 (file)
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -2484,7 +2484,7 @@ 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;
@@ -2542,7 +2542,7 @@ 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);
@@ -4097,6 +4097,11 @@ 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 dac8e7b16bc679e8550ee7781cbda5194791c535..4cb1c9be60732faef3633a1b6ea25a99a09f061c 100644 (file)
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -429,6 +429,8 @@ 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;
 };