Re: [PATCH 01/11] staging/iio: (iio_hwmon) Use devm_kzalloc

[Jonathan Cameron <jic23@kernel.org>]

On 01/31/2013 09:42 PM, Guenter Roeck wrote:
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This crossed with a little fix patch that changes one of the kzallocs
below.  The same trivial fix applies here so I've applied this with the obvious change.

Thanks,
> ---
>  drivers/staging/iio/iio_hwmon.c |   70 ++++++++++++---------------------------
>  1 file changed, 22 insertions(+), 48 deletions(-)
> 
> diff --git a/drivers/staging/iio/iio_hwmon.c b/drivers/staging/iio/iio_hwmon.c
> index c7a5f97..5456272 100644
> --- a/drivers/staging/iio/iio_hwmon.c
> +++ b/drivers/staging/iio/iio_hwmon.c
> @@ -55,63 +55,47 @@ static ssize_t iio_hwmon_read_val(struct device *dev,
>  	return sprintf(buf, "%d\n", result);
>  }
>  
> -static void iio_hwmon_free_attrs(struct iio_hwmon_state *st)
> -{
> -	int i;
> -	struct sensor_device_attribute *a;
> -	for (i = 0; i < st->num_channels; i++)
> -		if (st->attrs[i]) {
> -			a = to_sensor_dev_attr(
> -				container_of(st->attrs[i],
> -					     struct device_attribute,
> -					     attr));
> -			kfree(a);
> -		}
> -}
> -
>  static int iio_hwmon_probe(struct platform_device *pdev)
>  {
> +	struct device *dev = &pdev->dev;
>  	struct iio_hwmon_state *st;
>  	struct sensor_device_attribute *a;
>  	int ret, i;
>  	int in_i = 1, temp_i = 1, curr_i = 1;
>  	enum iio_chan_type type;
>  
> -	st = kzalloc(sizeof(*st), GFP_KERNEL);
> -	if (st == NULL) {
> -		ret = -ENOMEM;
> -		goto error_ret;
> -	}
> +	st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
> +	if (st == NULL)
> +		return -ENOMEM;
>  
> -	st->channels = iio_channel_get_all(dev_name(&pdev->dev));
> -	if (IS_ERR(st->channels)) {
> -		ret = PTR_ERR(st->channels);
> -		goto error_free_state;
> -	}
> +	st->channels = iio_channel_get_all(dev_name(dev));
> +	if (IS_ERR(st->channels))
> +		return PTR_ERR(st->channels);
>  
>  	/* count how many attributes we have */
>  	while (st->channels[st->num_channels].indio_dev)
>  		st->num_channels++;
>  
> -	st->attrs = kzalloc(sizeof(st->attrs) * (st->num_channels + 1),
this has changed to kzalloc(sizeof(*st->attrs) * (st->num_channels + 1),
so the following changed to equivalent.

> -			    GFP_KERNEL);
> +	st->attrs = devm_kzalloc(dev,
> +				 sizeof(st->attrs) * (st->num_channels + 1),
> +				 GFP_KERNEL);
>  	if (st->attrs == NULL) {
>  		ret = -ENOMEM;
>  		goto error_release_channels;
>  	}
> +
>  	for (i = 0; i < st->num_channels; i++) {
> -		a = kzalloc(sizeof(*a), GFP_KERNEL);
> +		a = devm_kzalloc(dev, sizeof(*a), GFP_KERNEL);
>  		if (a == NULL) {
>  			ret = -ENOMEM;
> -			goto error_free_attrs;
> +			goto error_release_channels;
>  		}
>  
>  		sysfs_attr_init(&a->dev_attr.attr);
>  		ret = iio_get_channel_type(&st->channels[i], &type);
> -		if (ret < 0) {
> -			kfree(a);
> -			goto error_free_attrs;
> -		}
> +		if (ret < 0)
> +			goto error_release_channels;
> +
>  		switch (type) {
>  		case IIO_VOLTAGE:
>  			a->dev_attr.attr.name = kasprintf(GFP_KERNEL,
> @@ -130,13 +114,11 @@ static int iio_hwmon_probe(struct platform_device *pdev)
>  			break;
>  		default:
>  			ret = -EINVAL;
> -			kfree(a);
> -			goto error_free_attrs;
> +			goto error_release_channels;
>  		}
>  		if (a->dev_attr.attr.name == NULL) {
> -			kfree(a);
>  			ret = -ENOMEM;
> -			goto error_free_attrs;
> +			goto error_release_channels;
>  		}
>  		a->dev_attr.show = iio_hwmon_read_val;
>  		a->dev_attr.attr.mode = S_IRUGO;
> @@ -146,11 +128,11 @@ static int iio_hwmon_probe(struct platform_device *pdev)
>  
>  	st->attr_group.attrs = st->attrs;
>  	platform_set_drvdata(pdev, st);
> -	ret = sysfs_create_group(&pdev->dev.kobj, &st->attr_group);
> +	ret = sysfs_create_group(&dev->kobj, &st->attr_group);
>  	if (ret < 0)
> -		goto error_free_attrs;
> +		goto error_release_channels;
>  
> -	st->hwmon_dev = hwmon_device_register(&pdev->dev);
> +	st->hwmon_dev = hwmon_device_register(dev);
>  	if (IS_ERR(st->hwmon_dev)) {
>  		ret = PTR_ERR(st->hwmon_dev);
>  		goto error_remove_group;
> @@ -158,15 +140,9 @@ static int iio_hwmon_probe(struct platform_device *pdev)
>  	return 0;
>  
>  error_remove_group:
> -	sysfs_remove_group(&pdev->dev.kobj, &st->attr_group);
> -error_free_attrs:
> -	iio_hwmon_free_attrs(st);
> -	kfree(st->attrs);
> +	sysfs_remove_group(&dev->kobj, &st->attr_group);
>  error_release_channels:
>  	iio_channel_release_all(st->channels);
> -error_free_state:
> -	kfree(st);
> -error_ret:
>  	return ret;
>  }
>  
> @@ -176,8 +152,6 @@ static int iio_hwmon_remove(struct platform_device *pdev)
>  
>  	hwmon_device_unregister(st->hwmon_dev);
>  	sysfs_remove_group(&pdev->dev.kobj, &st->attr_group);
> -	iio_hwmon_free_attrs(st);
> -	kfree(st->attrs);
>  	iio_channel_release_all(st->channels);
>  
>  	return 0;
>