Re: [PATCH 15/22] Input: iqs7222 - use cleanup facility for fwnodes

[Jeff LaBundy <jeff@labundy.com>]

Hi Dmitry,

On Tue, Sep 03, 2024 at 09:48:25PM -0700, Dmitry Torokhov wrote:
> Use __free(fwnode_handle) cleanup facility to ensure that references to
> acquired fwnodes are dropped at appropriate times automatically.
> 
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---
>  drivers/input/misc/iqs7222.c | 30 ++++++++++++++----------------
>  1 file changed, 14 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/input/misc/iqs7222.c b/drivers/input/misc/iqs7222.c
> index 9ca5a743f19f..d9b87606ff7a 100644
> --- a/drivers/input/misc/iqs7222.c
> +++ b/drivers/input/misc/iqs7222.c
> @@ -2385,9 +2385,9 @@ static int iqs7222_parse_chan(struct iqs7222_private *iqs7222,
>  	for (i = 0; i < ARRAY_SIZE(iqs7222_kp_events); i++) {
>  		const char *event_name = iqs7222_kp_events[i].name;
>  		u16 event_enable = iqs7222_kp_events[i].enable;
> -		struct fwnode_handle *event_node;
>  
> -		event_node = fwnode_get_named_child_node(chan_node, event_name);
> +		struct fwnode_handle *event_node __free(fwnode_handle) =
> +			fwnode_get_named_child_node(chan_node, event_name);

This leaves a newline amongst the declarations, but not in between the
declarations and code. I don't feel strongly against this, but it's
opposite of what I understand to be more common; please let me know in
case I have misunderstood. This comment applies to the other chunks as
well.

>  		if (!event_node)
>  			continue;
>  
> @@ -2408,7 +2408,6 @@ static int iqs7222_parse_chan(struct iqs7222_private *iqs7222,
>  				dev_err(&client->dev,
>  					"Invalid %s press timeout: %u\n",
>  					fwnode_get_name(event_node), val);
> -				fwnode_handle_put(event_node);
>  				return -EINVAL;
>  			}
>  
> @@ -2418,7 +2417,6 @@ static int iqs7222_parse_chan(struct iqs7222_private *iqs7222,
>  			dev_err(&client->dev,
>  				"Failed to read %s press timeout: %d\n",
>  				fwnode_get_name(event_node), error);
> -			fwnode_handle_put(event_node);
>  			return error;
>  		}
>  
> @@ -2429,7 +2427,6 @@ static int iqs7222_parse_chan(struct iqs7222_private *iqs7222,
>  					    dev_desc->touch_link - (i ? 0 : 2),
>  					    &iqs7222->kp_type[chan_index][i],
>  					    &iqs7222->kp_code[chan_index][i]);
> -		fwnode_handle_put(event_node);
>  		if (error)
>  			return error;
>  
> @@ -2604,10 +2601,10 @@ static int iqs7222_parse_sldr(struct iqs7222_private *iqs7222,
>  
>  	for (i = 0; i < ARRAY_SIZE(iqs7222_sl_events); i++) {
>  		const char *event_name = iqs7222_sl_events[i].name;
> -		struct fwnode_handle *event_node;
>  		enum iqs7222_reg_key_id reg_key;
>  
> -		event_node = fwnode_get_named_child_node(sldr_node, event_name);
> +		struct fwnode_handle *event_node __free(fwnode_handle) =
> +			fwnode_get_named_child_node(sldr_node, event_name);
>  		if (!event_node)
>  			continue;
>  
> @@ -2639,7 +2636,6 @@ static int iqs7222_parse_sldr(struct iqs7222_private *iqs7222,
>  					      : sldr_setup[4 + reg_offset],
>  					    NULL,
>  					    &iqs7222->sl_code[sldr_index][i]);
> -		fwnode_handle_put(event_node);
>  		if (error)
>  			return error;
>  
> @@ -2742,9 +2738,9 @@ static int iqs7222_parse_tpad(struct iqs7222_private *iqs7222,
>  
>  	for (i = 0; i < ARRAY_SIZE(iqs7222_tp_events); i++) {
>  		const char *event_name = iqs7222_tp_events[i].name;
> -		struct fwnode_handle *event_node;
>  
> -		event_node = fwnode_get_named_child_node(tpad_node, event_name);
> +		struct fwnode_handle *event_node __free(fwnode_handle) =
> +			fwnode_get_named_child_node(tpad_node, event_name);
>  		if (!event_node)
>  			continue;
>  
> @@ -2760,7 +2756,6 @@ static int iqs7222_parse_tpad(struct iqs7222_private *iqs7222,
>  					    iqs7222_tp_events[i].link, 1566,
>  					    NULL,
>  					    &iqs7222->tp_code[i]);
> -		fwnode_handle_put(event_node);
>  		if (error)
>  			return error;
>  
> @@ -2818,9 +2813,9 @@ static int iqs7222_parse_reg_grp(struct iqs7222_private *iqs7222,
>  				 int reg_grp_index)
>  {
>  	struct i2c_client *client = iqs7222->client;
> -	struct fwnode_handle *reg_grp_node;
>  	int error;
>  
> +	struct fwnode_handle *reg_grp_node __free(fwnode_handle) = NULL;
>  	if (iqs7222_reg_grp_names[reg_grp]) {
>  		char reg_grp_name[16];
>  
> @@ -2838,14 +2833,17 @@ static int iqs7222_parse_reg_grp(struct iqs7222_private *iqs7222,
>  
>  	error = iqs7222_parse_props(iqs7222, reg_grp_node, reg_grp_index,
>  				    reg_grp, IQS7222_REG_KEY_NONE);
> +	if (error)
> +		return error;
>  
> -	if (!error && iqs7222_parse_extra[reg_grp])
> +	if (iqs7222_parse_extra[reg_grp]) {
>  		error = iqs7222_parse_extra[reg_grp](iqs7222, reg_grp_node,
>  						     reg_grp_index);
> +		if (error)
> +			return error;
> +	}
>  
> -	fwnode_handle_put(reg_grp_node);
> -
> -	return error;
> +	return 0;
>  }
>  
>  static int iqs7222_parse_all(struct iqs7222_private *iqs7222)
> -- 
> 2.46.0.469.g59c65b2a67-goog
> 

Kind regards,
Jeff LaBundy