Re: [PATCH 3/3] iio: accel: bmc150-accel: Add rudimentary regulator support

[Jonathan Cameron <jic23@kernel.org>]

On Sun,  1 Nov 2020 13:28:33 +0100
Linus Walleij <linus.walleij@linaro.org> wrote:

> These Bosch accelerometers have two supplies, VDD and VDDIO.
> Add some rudimentary support to obtain and enable these
> regulators during probe() and disable them during remove()
> or on the errorpath.
> 
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Minor suggestion inline using new dev_err_probe()

thanks,

Jonathan
> ---
>  drivers/iio/accel/bmc150-accel-core.c | 37 +++++++++++++++++++++++++--
>  1 file changed, 35 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c
> index 0dafe4052856..a69a4f54d69a 100644
> --- a/drivers/iio/accel/bmc150-accel-core.c
> +++ b/drivers/iio/accel/bmc150-accel-core.c
> @@ -28,6 +28,7 @@
>  #include <linux/iio/trigger_consumer.h>
>  #include <linux/iio/triggered_buffer.h>
>  #include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
>  
>  #include "bmc150-accel.h"
>  
> @@ -184,6 +185,7 @@ enum bmc150_accel_trigger_id {
>  
>  struct bmc150_accel_data {
>  	struct regmap *regmap;
> +	struct regulator_bulk_data regulators[2];
>  	int irq;
>  	struct bmc150_accel_interrupt interrupts[BMC150_ACCEL_INTERRUPTS];
>  	struct bmc150_accel_trigger triggers[BMC150_ACCEL_TRIGGERS];
> @@ -1593,10 +1595,35 @@ int bmc150_accel_core_probe(struct device *dev, struct regmap *regmap, int irq,
>  				     &data->orientation);
>  	if (ret)
>  		return ret;
> +	/*
> +	 * VDD   is the analog and digital domain voltage supply
> +	 * VDDIO is the digital I/O voltage supply
> +	 */
> +	data->regulators[0].supply = "vdd";
> +	data->regulators[1].supply = "vddio";
> +	ret = devm_regulator_bulk_get(dev,
> +				      ARRAY_SIZE(data->regulators),
> +				      data->regulators);
> +	if (ret) {
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "Failed to get regulators %d\n", ret);
We have a magic print function for this now

return dev_err_probe(ret, "Failed to get regulators\n");

should do the job I think...

> +		return ret;
> +	}
> +	ret = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
> +				    data->regulators);
> +	if (ret) {
> +		dev_err(dev, "failed to enable regulators: %d\n", ret);
> +		return ret;
> +	}
> +	/*
> +	 * 2ms or 3ms power-on time according to datasheets, let's better
> +	 * be safe than sorry and set this delay to 5ms.
> +	 */
> +	msleep(5);
>  
>  	ret = bmc150_accel_chip_init(data);
>  	if (ret < 0)
> -		return ret;
> +		goto err_disable_regulators;
>  
>  	mutex_init(&data->mutex);
>  
> @@ -1613,7 +1640,7 @@ int bmc150_accel_core_probe(struct device *dev, struct regmap *regmap, int irq,
>  					 &bmc150_accel_buffer_ops);
>  	if (ret < 0) {
>  		dev_err(dev, "Failed: iio triggered buffer setup\n");
> -		return ret;
> +		goto err_disable_regulators;
>  	}
>  
>  	if (data->irq > 0) {
> @@ -1674,6 +1701,9 @@ int bmc150_accel_core_probe(struct device *dev, struct regmap *regmap, int irq,
>  	bmc150_accel_unregister_triggers(data, BMC150_ACCEL_TRIGGERS - 1);
>  err_buffer_cleanup:
>  	iio_triggered_buffer_cleanup(indio_dev);
> +err_disable_regulators:
> +	regulator_bulk_disable(ARRAY_SIZE(data->regulators),
> +			       data->regulators);
>  
>  	return ret;
>  }
> @@ -1698,6 +1728,9 @@ int bmc150_accel_core_remove(struct device *dev)
>  	bmc150_accel_set_mode(data, BMC150_ACCEL_SLEEP_MODE_DEEP_SUSPEND, 0);
>  	mutex_unlock(&data->mutex);
>  
> +	regulator_bulk_disable(ARRAY_SIZE(data->regulators),
> +			       data->regulators);
> +
>  	return 0;
>  }
>  EXPORT_SYMBOL_GPL(bmc150_accel_core_remove);