On Tue, 12 Apr 2016 12:31:00 +0200
Boris Brezillon <[email protected]> wrote:
> device_register() is calling ->get_voltage() as part of is sysfs attribute
^ its
> initialization process, and this functions might need to know the regulator
> constraints to return a valid value.
> This is at least true for the pwm regulator driver (when operating in
> continuous mode) which needs to know the minimum and maximum voltage values
> to calculate the current voltage:
>
> min_uV + (((max_uV - min_uV) * dutycycle) / 100);
>
> Move device_register() after set_machine_constraints() to make sure those
> constraints are correctly initialized when ->get_voltage() is called.
>
> Signed-off-by: Boris Brezillon <[email protected]>
> Reported-by: Stephen Barber <[email protected]>
> ---
> drivers/regulator/core.c | 20 ++++++++++----------
> 1 file changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
> index e0b7642..8258568 100644
> --- a/drivers/regulator/core.c
> +++ b/drivers/regulator/core.c
> @@ -3950,13 +3950,6 @@ regulator_register(const struct regulator_desc
> *regulator_desc,
> rdev->dev.parent = dev;
> dev_set_name(&rdev->dev, "regulator.%lu",
> (unsigned long) atomic_inc_return(®ulator_no));
> - ret = device_register(&rdev->dev);
> - if (ret != 0) {
> - put_device(&rdev->dev);
> - goto wash;
> - }
> -
> - dev_set_drvdata(&rdev->dev, rdev);
>
> /* set regulator constraints */
> if (init_data)
> @@ -3964,7 +3957,15 @@ regulator_register(const struct regulator_desc
> *regulator_desc,
>
> ret = set_machine_constraints(rdev, constraints);
> if (ret < 0)
> - goto scrub;
> + goto wash;
> +
> + ret = device_register(&rdev->dev);
> + if (ret != 0) {
> + put_device(&rdev->dev);
> + goto wash;
> + }
> +
> + dev_set_drvdata(&rdev->dev, rdev);
>
> if (init_data && init_data->supply_regulator)
> rdev->supply_name = init_data->supply_regulator;
> @@ -3993,8 +3994,6 @@ out:
>
> unset_supplies:
> unset_regulator_supplies(rdev);
> -
> -scrub:
> regulator_ena_gpio_free(rdev);
> device_unregister(&rdev->dev);
> /* device core frees rdev */
> @@ -4002,6 +4001,7 @@ scrub:
> goto out;
>
> wash:
> + kfree(rdev->constraints);
> regulator_ena_gpio_free(rdev);
> clean:
> kfree(rdev);
--
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
