On Wed, 2 Dec 2020 10:33:22 +0100
Stephan Gerhold <stephan@xxxxxxxxxxx> wrote:
> BMG160 needs VDD and VDDIO regulators that might need to be explicitly
> enabled. Add some rudimentary support to obtain and enable these
> regulators during probe() and disable them during remove()
> or on the error path.
>
> Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx>
Hi Stephan,
This one is a bit tricky due to the extensive use of devm_ managed
cleanup. Normally I'd be very fussy about ensuring remove order
is precise reverse of probe, but in this driver it isn't quite
already, due to that chip_init being before the interrupt allocation.
Having said that I'd rather not make it worse. Would you mind
using automated clean up of the regulator_enable as well via
devm_add_action_or_reset() call?
As a side note, should we not have more cleanup of chip_init()
in error paths, specifically putting the device into it's suspended
mode? Obviously nothing to do with your patch...
Thanks,
Jonathan
> ---
> drivers/iio/gyro/bmg160_core.c | 38 +++++++++++++++++++++++++++-------
> 1 file changed, 31 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/iio/gyro/bmg160_core.c b/drivers/iio/gyro/bmg160_core.c
> index 2d5015801a75..4baa4169c5a2 100644
> --- a/drivers/iio/gyro/bmg160_core.c
> +++ b/drivers/iio/gyro/bmg160_core.c
> @@ -19,6 +19,7 @@
> #include <linux/iio/trigger_consumer.h>
> #include <linux/iio/triggered_buffer.h>
> #include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> #include "bmg160.h"
>
> #define BMG160_IRQ_NAME "bmg160_event"
> @@ -92,6 +93,7 @@
>
> struct bmg160_data {
> struct regmap *regmap;
> + struct regulator_bulk_data regulators[2];
> struct iio_trigger *dready_trig;
> struct iio_trigger *motion_trig;
> struct iio_mount_matrix orientation;
> @@ -1077,14 +1079,28 @@ int bmg160_core_probe(struct device *dev, struct regmap *regmap, int irq,
> data->irq = irq;
> data->regmap = regmap;
>
> + data->regulators[0].supply = "vdd";
> + data->regulators[1].supply = "vddio";
> + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
> + data->regulators);
> + if (ret)
> + return dev_err_probe(dev, ret, "Failed to get regulators\n");
> +
> ret = iio_read_mount_matrix(dev, "mount-matrix",
> &data->orientation);
> if (ret)
> return ret;
Why not put regulator get and enable together?
>
> + ret = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
> + data->regulators);
> + if (ret < 0) {
> + dev_err(dev, "Failed to enable regulators: %d\n", ret);
> + return ret;
> + }
> +
If you were to use devm_add_action_or_reset() and a trivial wrapper
the disable would be automated, simplifying the error handling etc.
> ret = bmg160_chip_init(data);
> if (ret < 0)
> - return ret;
> + goto err_regulator_disable;
>
> mutex_init(&data->mutex);
>
> @@ -1107,28 +1123,32 @@ int bmg160_core_probe(struct device *dev, struct regmap *regmap, int irq,
> BMG160_IRQ_NAME,
> indio_dev);
> if (ret)
> - return ret;
> + goto err_regulator_disable;
>
> data->dready_trig = devm_iio_trigger_alloc(dev,
> "%s-dev%d",
> indio_dev->name,
> indio_dev->id);
> - if (!data->dready_trig)
> - return -ENOMEM;
> + if (!data->dready_trig) {
> + ret = -ENOMEM;
> + goto err_regulator_disable;
> + }
>
> data->motion_trig = devm_iio_trigger_alloc(dev,
> "%s-any-motion-dev%d",
> indio_dev->name,
> indio_dev->id);
> - if (!data->motion_trig)
> - return -ENOMEM;
> + if (!data->motion_trig) {
> + ret = -ENOMEM;
> + goto err_regulator_disable;
> + }
>
> data->dready_trig->dev.parent = dev;
> data->dready_trig->ops = &bmg160_trigger_ops;
> iio_trigger_set_drvdata(data->dready_trig, indio_dev);
> ret = iio_trigger_register(data->dready_trig);
> if (ret)
> - return ret;
> + goto err_regulator_disable;
>
> data->motion_trig->dev.parent = dev;
> data->motion_trig->ops = &bmg160_trigger_ops;
> @@ -1174,6 +1194,8 @@ int bmg160_core_probe(struct device *dev, struct regmap *regmap, int irq,
> iio_trigger_unregister(data->dready_trig);
> if (data->motion_trig)
> iio_trigger_unregister(data->motion_trig);
> +err_regulator_disable:
> + regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
>
> return ret;
> }
> @@ -1200,6 +1222,8 @@ void bmg160_core_remove(struct device *dev)
> mutex_lock(&data->mutex);
> bmg160_set_mode(data, BMG160_MODE_DEEP_SUSPEND);
> mutex_unlock(&data->mutex);
> +
> + regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
> }
> EXPORT_SYMBOL_GPL(bmg160_core_remove);
>
