diff mbox series

[14/22] Input: iqs626a - use cleanup facility for fwnodes

Message ID 20240904044814.1048062-1-dmitry.torokhov@gmail.com (mailing list archive)
State New
Headers show
Series Convert misc input drivers to use new cleanup facilities | expand

Commit Message

Dmitry Torokhov Sept. 4, 2024, 4:48 a.m. UTC
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/iqs626a.c | 22 ++++++----------------
 1 file changed, 6 insertions(+), 16 deletions(-)

Comments

Javier Carrasco Sept. 4, 2024, 11:10 a.m. UTC | #1
On 04/09/2024 06:48, 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/iqs626a.c | 22 ++++++----------------
>  1 file changed, 6 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/input/misc/iqs626a.c b/drivers/input/misc/iqs626a.c
> index 0dab54d3a060..7a6e6927f331 100644
> --- a/drivers/input/misc/iqs626a.c
> +++ b/drivers/input/misc/iqs626a.c
> @@ -462,7 +462,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  {
>  	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
>  	struct i2c_client *client = iqs626->client;
> -	struct fwnode_handle *ev_node;
>  	const char *ev_name;
>  	u8 *thresh, *hyst;
>  	unsigned int val;
> @@ -501,6 +500,7 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  		if (!iqs626_channels[ch_id].events[i])
>  			continue;
>  
> +		struct fwnode_handle *ev_node __free(fwnode_handle) = NULL;
>  		if (ch_id == IQS626_CH_TP_2 || ch_id == IQS626_CH_TP_3) {
>  			/*
>  			 * Trackpad touch events are simply described under the
> @@ -530,7 +530,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  					dev_err(&client->dev,
>  						"Invalid input type: %u\n",
>  						val);
> -					fwnode_handle_put(ev_node);
>  					return -EINVAL;
>  				}
>  
> @@ -545,7 +544,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  				dev_err(&client->dev,
>  					"Invalid %s channel hysteresis: %u\n",
>  					fwnode_get_name(ch_node), val);
> -				fwnode_handle_put(ev_node);
>  				return -EINVAL;
>  			}
>  
> @@ -566,7 +564,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  				dev_err(&client->dev,
>  					"Invalid %s channel threshold: %u\n",
>  					fwnode_get_name(ch_node), val);
> -				fwnode_handle_put(ev_node);
>  				return -EINVAL;
>  			}
>  
> @@ -575,8 +572,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  			else
>  				*(thresh + iqs626_events[i].th_offs) = val;
>  		}
> -
> -		fwnode_handle_put(ev_node);
>  	}
>  
>  	return 0;
> @@ -774,12 +769,12 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
>  	for (i = 0; i < iqs626_channels[ch_id].num_ch; i++) {
>  		u8 *ati_base = &sys_reg->tp_grp_reg.ch_reg_tp[i].ati_base;
>  		u8 *thresh = &sys_reg->tp_grp_reg.ch_reg_tp[i].thresh;
> -		struct fwnode_handle *tc_node;
>  		char tc_name[10];
>  
>  		snprintf(tc_name, sizeof(tc_name), "channel-%d", i);
>  
> -		tc_node = fwnode_get_named_child_node(ch_node, tc_name);
> +		struct fwnode_handle *tc_node __free(fwnode_handle) =
> +				fwnode_get_named_child_node(ch_node, tc_name);
>  		if (!tc_node)
>  			continue;
>  
> @@ -790,7 +785,6 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
>  				dev_err(&client->dev,
>  					"Invalid %s %s ATI base: %u\n",
>  					fwnode_get_name(ch_node), tc_name, val);
> -				fwnode_handle_put(tc_node);
>  				return -EINVAL;
>  			}
>  
> @@ -803,14 +797,11 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
>  				dev_err(&client->dev,
>  					"Invalid %s %s threshold: %u\n",
>  					fwnode_get_name(ch_node), tc_name, val);
> -				fwnode_handle_put(tc_node);
>  				return -EINVAL;
>  			}
>  
>  			*thresh = val;
>  		}
> -
> -		fwnode_handle_put(tc_node);
>  	}
>  
>  	if (!fwnode_property_present(ch_node, "linux,keycodes"))
> @@ -1233,7 +1224,6 @@ static int iqs626_parse_prop(struct iqs626_private *iqs626)
>  {
>  	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
>  	struct i2c_client *client = iqs626->client;
> -	struct fwnode_handle *ch_node;
>  	unsigned int val;
>  	int error, i;
>  	u16 general;
> @@ -1375,13 +1365,13 @@ static int iqs626_parse_prop(struct iqs626_private *iqs626)
>  	sys_reg->active = 0;
>  
>  	for (i = 0; i < ARRAY_SIZE(iqs626_channels); i++) {
> -		ch_node = device_get_named_child_node(&client->dev,
> -						      iqs626_channels[i].name);
> +		struct fwnode_handle *ch_node __free(fwnode_handle) =
> +			device_get_named_child_node(&client->dev,
> +						    iqs626_channels[i].name);
>  		if (!ch_node)
>  			continue;
>  
>  		error = iqs626_parse_channel(iqs626, ch_node, i);
> -		fwnode_handle_put(ch_node);
>  		if (error)
>  			return error;
>  

Reviewed-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Jeff LaBundy Sept. 9, 2024, 12:02 a.m. UTC | #2
Hi Dmitry,

On Tue, Sep 03, 2024 at 09:48:13PM -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/iqs626a.c | 22 ++++++----------------
>  1 file changed, 6 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/input/misc/iqs626a.c b/drivers/input/misc/iqs626a.c
> index 0dab54d3a060..7a6e6927f331 100644
> --- a/drivers/input/misc/iqs626a.c
> +++ b/drivers/input/misc/iqs626a.c
> @@ -462,7 +462,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  {
>  	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
>  	struct i2c_client *client = iqs626->client;
> -	struct fwnode_handle *ev_node;
>  	const char *ev_name;
>  	u8 *thresh, *hyst;
>  	unsigned int val;
> @@ -501,6 +500,7 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  		if (!iqs626_channels[ch_id].events[i])
>  			continue;
>  
> +		struct fwnode_handle *ev_node __free(fwnode_handle) = NULL;

This seems to deviate from what I understand to be a more conventional
style of declaring variables at the top of the scope, and separate from
actual code, like below:


	for (i = 0; i < ARRAY_SIZE(iqs626_events); i++) {
		struct fwnode_handle *ev_node __free(fwnode_handle);

		if (!iqs626_channels[ch_id].events[i])
			continue;

I also did not see any reason to explicitly declare the variable as NULL;
let me know in case I have misunderstood.

>  		if (ch_id == IQS626_CH_TP_2 || ch_id == IQS626_CH_TP_3) {
>  			/*
>  			 * Trackpad touch events are simply described under the
> @@ -530,7 +530,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  					dev_err(&client->dev,
>  						"Invalid input type: %u\n",
>  						val);
> -					fwnode_handle_put(ev_node);
>  					return -EINVAL;
>  				}
>  
> @@ -545,7 +544,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  				dev_err(&client->dev,
>  					"Invalid %s channel hysteresis: %u\n",
>  					fwnode_get_name(ch_node), val);
> -				fwnode_handle_put(ev_node);
>  				return -EINVAL;
>  			}
>  
> @@ -566,7 +564,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  				dev_err(&client->dev,
>  					"Invalid %s channel threshold: %u\n",
>  					fwnode_get_name(ch_node), val);
> -				fwnode_handle_put(ev_node);
>  				return -EINVAL;
>  			}
>  
> @@ -575,8 +572,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
>  			else
>  				*(thresh + iqs626_events[i].th_offs) = val;
>  		}
> -
> -		fwnode_handle_put(ev_node);
>  	}
>  
>  	return 0;
> @@ -774,12 +769,12 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
>  	for (i = 0; i < iqs626_channels[ch_id].num_ch; i++) {
>  		u8 *ati_base = &sys_reg->tp_grp_reg.ch_reg_tp[i].ati_base;
>  		u8 *thresh = &sys_reg->tp_grp_reg.ch_reg_tp[i].thresh;
> -		struct fwnode_handle *tc_node;
>  		char tc_name[10];
>  
>  		snprintf(tc_name, sizeof(tc_name), "channel-%d", i);
>  
> -		tc_node = fwnode_get_named_child_node(ch_node, tc_name);
> +		struct fwnode_handle *tc_node __free(fwnode_handle) =
> +				fwnode_get_named_child_node(ch_node, tc_name);

Same here.

>  		if (!tc_node)
>  			continue;
>  
> @@ -790,7 +785,6 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
>  				dev_err(&client->dev,
>  					"Invalid %s %s ATI base: %u\n",
>  					fwnode_get_name(ch_node), tc_name, val);
> -				fwnode_handle_put(tc_node);
>  				return -EINVAL;
>  			}
>  
> @@ -803,14 +797,11 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
>  				dev_err(&client->dev,
>  					"Invalid %s %s threshold: %u\n",
>  					fwnode_get_name(ch_node), tc_name, val);
> -				fwnode_handle_put(tc_node);
>  				return -EINVAL;
>  			}
>  
>  			*thresh = val;
>  		}
> -
> -		fwnode_handle_put(tc_node);
>  	}
>  
>  	if (!fwnode_property_present(ch_node, "linux,keycodes"))
> @@ -1233,7 +1224,6 @@ static int iqs626_parse_prop(struct iqs626_private *iqs626)
>  {
>  	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
>  	struct i2c_client *client = iqs626->client;
> -	struct fwnode_handle *ch_node;
>  	unsigned int val;
>  	int error, i;
>  	u16 general;
> @@ -1375,13 +1365,13 @@ static int iqs626_parse_prop(struct iqs626_private *iqs626)
>  	sys_reg->active = 0;
>  
>  	for (i = 0; i < ARRAY_SIZE(iqs626_channels); i++) {
> -		ch_node = device_get_named_child_node(&client->dev,
> -						      iqs626_channels[i].name);
> +		struct fwnode_handle *ch_node __free(fwnode_handle) =
> +			device_get_named_child_node(&client->dev,
> +						    iqs626_channels[i].name);
>  		if (!ch_node)
>  			continue;
>  
>  		error = iqs626_parse_channel(iqs626, ch_node, i);
> -		fwnode_handle_put(ch_node);
>  		if (error)
>  			return error;
>  
> -- 
> 2.46.0.469.g59c65b2a67-goog
> 

Kind regards,
Jeff LaBundy
Dmitry Torokhov Sept. 9, 2024, 1:31 a.m. UTC | #3
Hi Jeff,

On Sun, Sep 08, 2024 at 07:02:41PM -0500, Jeff LaBundy wrote:
> Hi Dmitry,
> 
> On Tue, Sep 03, 2024 at 09:48:13PM -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/iqs626a.c | 22 ++++++----------------
> >  1 file changed, 6 insertions(+), 16 deletions(-)
> > 
> > diff --git a/drivers/input/misc/iqs626a.c b/drivers/input/misc/iqs626a.c
> > index 0dab54d3a060..7a6e6927f331 100644
> > --- a/drivers/input/misc/iqs626a.c
> > +++ b/drivers/input/misc/iqs626a.c
> > @@ -462,7 +462,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> >  {
> >  	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
> >  	struct i2c_client *client = iqs626->client;
> > -	struct fwnode_handle *ev_node;
> >  	const char *ev_name;
> >  	u8 *thresh, *hyst;
> >  	unsigned int val;
> > @@ -501,6 +500,7 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> >  		if (!iqs626_channels[ch_id].events[i])
> >  			continue;
> >  
> > +		struct fwnode_handle *ev_node __free(fwnode_handle) = NULL;
> 
> This seems to deviate from what I understand to be a more conventional
> style of declaring variables at the top of the scope, and separate from
> actual code, like below:

This is follows Linus' guidance on combining declaration and
initialization for variables using __free() cleanup annotations (where
possible). These annotations are the reason for dropping
-Wdeclaration-after-statement from our makefiles. See b5ec6fd286df
("kbuild: Drop -Wdeclaration-after-statement") and discussion in
https://lore.kernel.org/all/CAHk-=wi-RyoUhbChiVaJZoZXheAwnJ7OO=Gxe85BkPAd93TwDA@mail.gmail.com

> 
> 
> 	for (i = 0; i < ARRAY_SIZE(iqs626_events); i++) {
> 		struct fwnode_handle *ev_node __free(fwnode_handle);
> 
> 		if (!iqs626_channels[ch_id].events[i])
> 			continue;

This will result in attempt to "put" a garbage pointer if we follow
"continue" code path. In general __free() pointers have to be
initialized, either to NULL or to a valid object (assuming that cleanup
function can deal with NULLs).

> 
> I also did not see any reason to explicitly declare the variable as NULL;
> let me know in case I have misunderstood.

See the above. Yes, in this particular case it will get a value in both
branches, but I feel it is too fragile and may get messed up if someone
refactors code.

> 
> >  		if (ch_id == IQS626_CH_TP_2 || ch_id == IQS626_CH_TP_3) {
> >  			/*
> >  			 * Trackpad touch events are simply described under the
> > @@ -530,7 +530,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> >  					dev_err(&client->dev,
> >  						"Invalid input type: %u\n",
> >  						val);
> > -					fwnode_handle_put(ev_node);
> >  					return -EINVAL;
> >  				}
> >  
> > @@ -545,7 +544,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> >  				dev_err(&client->dev,
> >  					"Invalid %s channel hysteresis: %u\n",
> >  					fwnode_get_name(ch_node), val);
> > -				fwnode_handle_put(ev_node);
> >  				return -EINVAL;
> >  			}
> >  
> > @@ -566,7 +564,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> >  				dev_err(&client->dev,
> >  					"Invalid %s channel threshold: %u\n",
> >  					fwnode_get_name(ch_node), val);
> > -				fwnode_handle_put(ev_node);
> >  				return -EINVAL;
> >  			}
> >  
> > @@ -575,8 +572,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> >  			else
> >  				*(thresh + iqs626_events[i].th_offs) = val;
> >  		}
> > -
> > -		fwnode_handle_put(ev_node);
> >  	}
> >  
> >  	return 0;
> > @@ -774,12 +769,12 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
> >  	for (i = 0; i < iqs626_channels[ch_id].num_ch; i++) {
> >  		u8 *ati_base = &sys_reg->tp_grp_reg.ch_reg_tp[i].ati_base;
> >  		u8 *thresh = &sys_reg->tp_grp_reg.ch_reg_tp[i].thresh;
> > -		struct fwnode_handle *tc_node;
> >  		char tc_name[10];
> >  
> >  		snprintf(tc_name, sizeof(tc_name), "channel-%d", i);
> >  
> > -		tc_node = fwnode_get_named_child_node(ch_node, tc_name);
> > +		struct fwnode_handle *tc_node __free(fwnode_handle) =
> > +				fwnode_get_named_child_node(ch_node, tc_name);
> 
> Same here.

Yes, combining declaration and initialization is preferred for such
pointers.

Thanks.
Jeff LaBundy Sept. 10, 2024, 3:12 p.m. UTC | #4
Hi Dmitry,

On Sun, Sep 08, 2024 at 06:31:26PM -0700, Dmitry Torokhov wrote:
> Hi Jeff,
> 
> On Sun, Sep 08, 2024 at 07:02:41PM -0500, Jeff LaBundy wrote:
> > Hi Dmitry,
> > 
> > On Tue, Sep 03, 2024 at 09:48:13PM -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/iqs626a.c | 22 ++++++----------------
> > >  1 file changed, 6 insertions(+), 16 deletions(-)
> > > 
> > > diff --git a/drivers/input/misc/iqs626a.c b/drivers/input/misc/iqs626a.c
> > > index 0dab54d3a060..7a6e6927f331 100644
> > > --- a/drivers/input/misc/iqs626a.c
> > > +++ b/drivers/input/misc/iqs626a.c
> > > @@ -462,7 +462,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> > >  {
> > >  	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
> > >  	struct i2c_client *client = iqs626->client;
> > > -	struct fwnode_handle *ev_node;
> > >  	const char *ev_name;
> > >  	u8 *thresh, *hyst;
> > >  	unsigned int val;
> > > @@ -501,6 +500,7 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> > >  		if (!iqs626_channels[ch_id].events[i])
> > >  			continue;
> > >  
> > > +		struct fwnode_handle *ev_node __free(fwnode_handle) = NULL;
> > 
> > This seems to deviate from what I understand to be a more conventional
> > style of declaring variables at the top of the scope, and separate from
> > actual code, like below:
> 
> This is follows Linus' guidance on combining declaration and
> initialization for variables using __free() cleanup annotations (where
> possible). These annotations are the reason for dropping
> -Wdeclaration-after-statement from our makefiles. See b5ec6fd286df
> ("kbuild: Drop -Wdeclaration-after-statement") and discussion in
> https://lore.kernel.org/all/CAHk-=wi-RyoUhbChiVaJZoZXheAwnJ7OO=Gxe85BkPAd93TwDA@mail.gmail.com

Understood; thank you for the reference.

> 
> > 
> > 
> > 	for (i = 0; i < ARRAY_SIZE(iqs626_events); i++) {
> > 		struct fwnode_handle *ev_node __free(fwnode_handle);
> > 
> > 		if (!iqs626_channels[ch_id].events[i])
> > 			continue;
> 
> This will result in attempt to "put" a garbage pointer if we follow
> "continue" code path. In general __free() pointers have to be
> initialized, either to NULL or to a valid object (assuming that cleanup
> function can deal with NULLs).

Great catch; I missed the fact that fwnode_handle_put() is implicitly
being called in all exit paths now.

> 
> > 
> > I also did not see any reason to explicitly declare the variable as NULL;
> > let me know in case I have misunderstood.
> 
> See the above. Yes, in this particular case it will get a value in both
> branches, but I feel it is too fragile and may get messed up if someone
> refactors code.

Based on the above point, I agree with your approach.

> 
> > 
> > >  		if (ch_id == IQS626_CH_TP_2 || ch_id == IQS626_CH_TP_3) {
> > >  			/*
> > >  			 * Trackpad touch events are simply described under the
> > > @@ -530,7 +530,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> > >  					dev_err(&client->dev,
> > >  						"Invalid input type: %u\n",
> > >  						val);
> > > -					fwnode_handle_put(ev_node);
> > >  					return -EINVAL;
> > >  				}
> > >  
> > > @@ -545,7 +544,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> > >  				dev_err(&client->dev,
> > >  					"Invalid %s channel hysteresis: %u\n",
> > >  					fwnode_get_name(ch_node), val);
> > > -				fwnode_handle_put(ev_node);
> > >  				return -EINVAL;
> > >  			}
> > >  
> > > @@ -566,7 +564,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> > >  				dev_err(&client->dev,
> > >  					"Invalid %s channel threshold: %u\n",
> > >  					fwnode_get_name(ch_node), val);
> > > -				fwnode_handle_put(ev_node);
> > >  				return -EINVAL;
> > >  			}
> > >  
> > > @@ -575,8 +572,6 @@ iqs626_parse_events(struct iqs626_private *iqs626,
> > >  			else
> > >  				*(thresh + iqs626_events[i].th_offs) = val;
> > >  		}
> > > -
> > > -		fwnode_handle_put(ev_node);
> > >  	}
> > >  
> > >  	return 0;
> > > @@ -774,12 +769,12 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
> > >  	for (i = 0; i < iqs626_channels[ch_id].num_ch; i++) {
> > >  		u8 *ati_base = &sys_reg->tp_grp_reg.ch_reg_tp[i].ati_base;
> > >  		u8 *thresh = &sys_reg->tp_grp_reg.ch_reg_tp[i].thresh;
> > > -		struct fwnode_handle *tc_node;
> > >  		char tc_name[10];
> > >  
> > >  		snprintf(tc_name, sizeof(tc_name), "channel-%d", i);
> > >  
> > > -		tc_node = fwnode_get_named_child_node(ch_node, tc_name);
> > > +		struct fwnode_handle *tc_node __free(fwnode_handle) =
> > > +				fwnode_get_named_child_node(ch_node, tc_name);
> > 
> > Same here.
> 
> Yes, combining declaration and initialization is preferred for such
> pointers.

ACK. Please feel free to add:

Reviewed-by: Jeff LaBundy <jeff@labundy.com>

> 
> Thanks.
> 
> -- 
> Dmitry

Thank you for the discussion!

Kind regards,
Jeff LaBundy
diff mbox series

Patch

diff --git a/drivers/input/misc/iqs626a.c b/drivers/input/misc/iqs626a.c
index 0dab54d3a060..7a6e6927f331 100644
--- a/drivers/input/misc/iqs626a.c
+++ b/drivers/input/misc/iqs626a.c
@@ -462,7 +462,6 @@  iqs626_parse_events(struct iqs626_private *iqs626,
 {
 	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
 	struct i2c_client *client = iqs626->client;
-	struct fwnode_handle *ev_node;
 	const char *ev_name;
 	u8 *thresh, *hyst;
 	unsigned int val;
@@ -501,6 +500,7 @@  iqs626_parse_events(struct iqs626_private *iqs626,
 		if (!iqs626_channels[ch_id].events[i])
 			continue;
 
+		struct fwnode_handle *ev_node __free(fwnode_handle) = NULL;
 		if (ch_id == IQS626_CH_TP_2 || ch_id == IQS626_CH_TP_3) {
 			/*
 			 * Trackpad touch events are simply described under the
@@ -530,7 +530,6 @@  iqs626_parse_events(struct iqs626_private *iqs626,
 					dev_err(&client->dev,
 						"Invalid input type: %u\n",
 						val);
-					fwnode_handle_put(ev_node);
 					return -EINVAL;
 				}
 
@@ -545,7 +544,6 @@  iqs626_parse_events(struct iqs626_private *iqs626,
 				dev_err(&client->dev,
 					"Invalid %s channel hysteresis: %u\n",
 					fwnode_get_name(ch_node), val);
-				fwnode_handle_put(ev_node);
 				return -EINVAL;
 			}
 
@@ -566,7 +564,6 @@  iqs626_parse_events(struct iqs626_private *iqs626,
 				dev_err(&client->dev,
 					"Invalid %s channel threshold: %u\n",
 					fwnode_get_name(ch_node), val);
-				fwnode_handle_put(ev_node);
 				return -EINVAL;
 			}
 
@@ -575,8 +572,6 @@  iqs626_parse_events(struct iqs626_private *iqs626,
 			else
 				*(thresh + iqs626_events[i].th_offs) = val;
 		}
-
-		fwnode_handle_put(ev_node);
 	}
 
 	return 0;
@@ -774,12 +769,12 @@  static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
 	for (i = 0; i < iqs626_channels[ch_id].num_ch; i++) {
 		u8 *ati_base = &sys_reg->tp_grp_reg.ch_reg_tp[i].ati_base;
 		u8 *thresh = &sys_reg->tp_grp_reg.ch_reg_tp[i].thresh;
-		struct fwnode_handle *tc_node;
 		char tc_name[10];
 
 		snprintf(tc_name, sizeof(tc_name), "channel-%d", i);
 
-		tc_node = fwnode_get_named_child_node(ch_node, tc_name);
+		struct fwnode_handle *tc_node __free(fwnode_handle) =
+				fwnode_get_named_child_node(ch_node, tc_name);
 		if (!tc_node)
 			continue;
 
@@ -790,7 +785,6 @@  static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
 				dev_err(&client->dev,
 					"Invalid %s %s ATI base: %u\n",
 					fwnode_get_name(ch_node), tc_name, val);
-				fwnode_handle_put(tc_node);
 				return -EINVAL;
 			}
 
@@ -803,14 +797,11 @@  static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
 				dev_err(&client->dev,
 					"Invalid %s %s threshold: %u\n",
 					fwnode_get_name(ch_node), tc_name, val);
-				fwnode_handle_put(tc_node);
 				return -EINVAL;
 			}
 
 			*thresh = val;
 		}
-
-		fwnode_handle_put(tc_node);
 	}
 
 	if (!fwnode_property_present(ch_node, "linux,keycodes"))
@@ -1233,7 +1224,6 @@  static int iqs626_parse_prop(struct iqs626_private *iqs626)
 {
 	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
 	struct i2c_client *client = iqs626->client;
-	struct fwnode_handle *ch_node;
 	unsigned int val;
 	int error, i;
 	u16 general;
@@ -1375,13 +1365,13 @@  static int iqs626_parse_prop(struct iqs626_private *iqs626)
 	sys_reg->active = 0;
 
 	for (i = 0; i < ARRAY_SIZE(iqs626_channels); i++) {
-		ch_node = device_get_named_child_node(&client->dev,
-						      iqs626_channels[i].name);
+		struct fwnode_handle *ch_node __free(fwnode_handle) =
+			device_get_named_child_node(&client->dev,
+						    iqs626_channels[i].name);
 		if (!ch_node)
 			continue;
 
 		error = iqs626_parse_channel(iqs626, ch_node, i);
-		fwnode_handle_put(ch_node);
 		if (error)
 			return error;