Re: [PATCH v4 15/15] iio: dac: ltc2688: Use device_for_each_child_node_scoped()

["Nuno Sá" <noname.nuno@gmail.com>]

On Sat, 2024-02-17 at 16:42 +0000, Jonathan Cameron wrote:
> From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> 
> Switching to the _scoped() version removes the need for manual
> calling of fwnode_handle_put() in the paths where the code
> exits the loop early. In this case that's all in error paths.
> 
> Cc: Nuno Sá <nuno.sa@analog.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---

Tested-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>

> v4: Moved alignment changes back to patch 4.
> v3: Tweaked the alignment after comments from Andy.
> 
>  drivers/iio/dac/ltc2688.c | 24 ++++++------------------
>  1 file changed, 6 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/iio/dac/ltc2688.c b/drivers/iio/dac/ltc2688.c
> index fc8eb53c65be..b71df03fc13b 100644
> --- a/drivers/iio/dac/ltc2688.c
> +++ b/drivers/iio/dac/ltc2688.c
> @@ -746,26 +746,21 @@ static int ltc2688_span_lookup(const struct
> ltc2688_state *st, int min, int max)
>  static int ltc2688_channel_config(struct ltc2688_state *st)
>  {
>  	struct device *dev = &st->spi->dev;
> -	struct fwnode_handle *child;
>  	u32 reg, clk_input, val, tmp[2];
>  	int ret, span;
>  
> -	device_for_each_child_node(dev, child) {
> +	device_for_each_child_node_scoped(dev, child) {
>  		struct ltc2688_chan *chan;
>  
>  		ret = fwnode_property_read_u32(child, "reg", &reg);
> -		if (ret) {
> -			fwnode_handle_put(child);
> +		if (ret)
>  			return dev_err_probe(dev, ret,
>  					     "Failed to get reg property\n");
> -		}
>  
> -		if (reg >= LTC2688_DAC_CHANNELS) {
> -			fwnode_handle_put(child);
> +		if (reg >= LTC2688_DAC_CHANNELS)
>  			return dev_err_probe(dev, -EINVAL,
>  					     "reg bigger than: %d\n",
>  					     LTC2688_DAC_CHANNELS);
> -		}
>  
>  		val = 0;
>  		chan = &st->channels[reg];
> @@ -786,12 +781,10 @@ static int ltc2688_channel_config(struct ltc2688_state
> *st)
>  		if (!ret) {
>  			span = ltc2688_span_lookup(st, (int)tmp[0] / 1000,
>  						   tmp[1] / 1000);
> -			if (span < 0) {
> -				fwnode_handle_put(child);
> +			if (span < 0)
>  				return dev_err_probe(dev, -EINVAL,
>  						     "output range not
> valid:[%d %d]\n",
>  						     tmp[0], tmp[1]);
> -			}
>  
>  			val |= FIELD_PREP(LTC2688_CH_SPAN_MSK, span);
>  		}
> @@ -800,17 +793,14 @@ static int ltc2688_channel_config(struct ltc2688_state
> *st)
>  					       &clk_input);
>  		if (!ret) {
>  			if (clk_input >= LTC2688_CH_TGP_MAX) {
> -				fwnode_handle_put(child);
>  				return dev_err_probe(dev, -EINVAL,
>  						     "toggle-dither-input inv
> value(%d)\n",
>  						     clk_input);
>  			}
>  
>  			ret = ltc2688_tgp_clk_setup(st, chan, child,
> clk_input);
> -			if (ret) {
> -				fwnode_handle_put(child);
> +			if (ret)
>  				return ret;
> -			}
>  
>  			/*
>  			 * 0 means software toggle which is the default mode.
> @@ -844,11 +834,9 @@ static int ltc2688_channel_config(struct ltc2688_state
> *st)
>  
>  		ret = regmap_write(st->regmap, LTC2688_CMD_CH_SETTING(reg),
>  				   val);
> -		if (ret) {
> -			fwnode_handle_put(child);
> +		if (ret)
>  			return dev_err_probe(dev, -EINVAL,
>  					     "failed to set chan
> settings\n");
> -		}
>  	}
>  
>  	return 0;