[PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[Abhinav Jain]

Remove of_node_put from node_ctrl and node struct device_nodes.
Move the declaration to initialization for ensuring scope sanity.

Suggested-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Abhinav Jain <jain.abhinav177@gmail.com>
---
 drivers/i2c/busses/i2c-mpc.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index 8d73c0f405ed..c4223556b3b8 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -304,13 +304,12 @@ static void mpc_i2c_setup_512x(struct device_node *node,
 					 struct mpc_i2c *i2c,
 					 u32 clock)
 {
-	struct device_node *node_ctrl;
 	void __iomem *ctrl;
 	u32 idx;
 
 	/* Enable I2C interrupts for mpc5121 */
-	node_ctrl = of_find_compatible_node(NULL, NULL,
-					    "fsl,mpc5121-i2c-ctrl");
+	struct device_node *node_ctrl __free(device_node) =
+		of_find_compatible_node(NULL, NULL, "fsl,mpc5121-i2c-ctrl");
 	if (node_ctrl) {
 		ctrl = of_iomap(node_ctrl, 0);
 		if (ctrl) {
@@ -321,7 +320,6 @@ static void mpc_i2c_setup_512x(struct device_node *node,
 			setbits32(ctrl, 1 << (24 + idx * 2));
 			iounmap(ctrl);
 		}
-		of_node_put(node_ctrl);
 	}
 
 	/* The clock setup for the 52xx works also fine for the 512x */
@@ -358,11 +356,11 @@ static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = {
 
 static u32 mpc_i2c_get_sec_cfg_8xxx(void)
 {
-	struct device_node *node;
 	u32 __iomem *reg;
 	u32 val = 0;
 
-	node = of_find_node_by_name(NULL, "global-utilities");
+	struct device_node *node __free(device_node) =
+		of_find_node_by_name(NULL, "global-utilities");
 	if (node) {
 		const u32 *prop = of_get_property(node, "reg", NULL);
 		if (prop) {
@@ -383,7 +381,6 @@ static u32 mpc_i2c_get_sec_cfg_8xxx(void)
 			iounmap(reg);
 		}
 	}
-	of_node_put(node);
 
 	return val;
 }
-- 
2.34.1

Re: [PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[Andi Shyti]

Hi Abhinav,

>  	/* Enable I2C interrupts for mpc5121 */
> -	node_ctrl = of_find_compatible_node(NULL, NULL,
> -					    "fsl,mpc5121-i2c-ctrl");
> +	struct device_node *node_ctrl __free(device_node) =

How have you tested this?

Andi

Re: [PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[Chris Packham]

On 16/04/24 08:54, Andi Shyti wrote:
> Hi Abhinav,
>
>>   	/* Enable I2C interrupts for mpc5121 */
>> -	node_ctrl = of_find_compatible_node(NULL, NULL,
>> -					    "fsl,mpc5121-i2c-ctrl");
>> +	struct device_node *node_ctrl __free(device_node) =
> How have you tested this?

I'm not sure I know anyone that still has a mpc5121. Maybe someone on 
linuxppc-dev?

I did try to take the patch for a spin on my T2081RDB but I'm having 
some userland issues on it for some reason (unrelated to this change). 
The kernel boot does discover a few peripherals hanging of the I2C 
interface but I'm not in a position to offer up a Tested-by and I've run 
out of time to debug why my board is unhappy.

Re: [PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[Chris Packham]

On 16/04/24 04:12, Abhinav Jain wrote:
> Remove of_node_put from node_ctrl and node struct device_nodes.
> Move the declaration to initialization for ensuring scope sanity.
>
> Suggested-by: Julia Lawall <julia.lawall@inria.fr>
> Signed-off-by: Abhinav Jain <jain.abhinav177@gmail.com>

Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>

> ---
>   drivers/i2c/busses/i2c-mpc.c | 11 ++++-------
>   1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
> index 8d73c0f405ed..c4223556b3b8 100644
> --- a/drivers/i2c/busses/i2c-mpc.c
> +++ b/drivers/i2c/busses/i2c-mpc.c
> @@ -304,13 +304,12 @@ static void mpc_i2c_setup_512x(struct device_node *node,
>   					 struct mpc_i2c *i2c,
>   					 u32 clock)
>   {
> -	struct device_node *node_ctrl;
>   	void __iomem *ctrl;
>   	u32 idx;
>   
>   	/* Enable I2C interrupts for mpc5121 */
> -	node_ctrl = of_find_compatible_node(NULL, NULL,
> -					    "fsl,mpc5121-i2c-ctrl");
> +	struct device_node *node_ctrl __free(device_node) =
> +		of_find_compatible_node(NULL, NULL, "fsl,mpc5121-i2c-ctrl");
>   	if (node_ctrl) {
>   		ctrl = of_iomap(node_ctrl, 0);
>   		if (ctrl) {
> @@ -321,7 +320,6 @@ static void mpc_i2c_setup_512x(struct device_node *node,
>   			setbits32(ctrl, 1 << (24 + idx * 2));
>   			iounmap(ctrl);
>   		}
> -		of_node_put(node_ctrl);
>   	}
>   
>   	/* The clock setup for the 52xx works also fine for the 512x */
> @@ -358,11 +356,11 @@ static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = {
>   
>   static u32 mpc_i2c_get_sec_cfg_8xxx(void)
>   {
> -	struct device_node *node;
>   	u32 __iomem *reg;
>   	u32 val = 0;
>   
> -	node = of_find_node_by_name(NULL, "global-utilities");
> +	struct device_node *node __free(device_node) =
> +		of_find_node_by_name(NULL, "global-utilities");
>   	if (node) {
>   		const u32 *prop = of_get_property(node, "reg", NULL);
>   		if (prop) {
> @@ -383,7 +381,6 @@ static u32 mpc_i2c_get_sec_cfg_8xxx(void)
>   			iounmap(reg);
>   		}
>   	}
> -	of_node_put(node);
>   
>   	return val;
>   }

Re: [PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[Andi Shyti]

Hi Chris,

On Tue, Apr 16, 2024 at 03:59:13AM +0000, Chris Packham wrote:
> On 16/04/24 08:54, Andi Shyti wrote:
> >>   	/* Enable I2C interrupts for mpc5121 */
> >> -	node_ctrl = of_find_compatible_node(NULL, NULL,
> >> -					    "fsl,mpc5121-i2c-ctrl");
> >> +	struct device_node *node_ctrl __free(device_node) =
> > How have you tested this?
> 
> I'm not sure I know anyone that still has a mpc5121. Maybe someone on 
> linuxppc-dev?

that's why I was asking, this would be the first driver in i2c
using Rob's __free(device_node).

> I did try to take the patch for a spin on my T2081RDB but I'm having 
> some userland issues on it for some reason (unrelated to this change). 
> The kernel boot does discover a few peripherals hanging of the I2C 
> interface but I'm not in a position to offer up a Tested-by and I've run 
> out of time to debug why my board is unhappy.

Thanks for giving it a try.

Andi

Re: [PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[Andi Shyti]

On Tue, Apr 16, 2024 at 04:07:48PM +0200, Andi Shyti wrote:
> On Tue, Apr 16, 2024 at 03:59:13AM +0000, Chris Packham wrote:
> > On 16/04/24 08:54, Andi Shyti wrote:
> > >>   	/* Enable I2C interrupts for mpc5121 */
> > >> -	node_ctrl = of_find_compatible_node(NULL, NULL,
> > >> -					    "fsl,mpc5121-i2c-ctrl");
> > >> +	struct device_node *node_ctrl __free(device_node) =
> > > How have you tested this?
> > 
> > I'm not sure I know anyone that still has a mpc5121. Maybe someone on 
> > linuxppc-dev?
> 
> that's why I was asking, this would be the first driver in i2c
> using Rob's __free(device_node).

Jonathan's, of course :-)

Andi

Re: [PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[Andi Shyti]

Hi

On Mon, 15 Apr 2024 16:12:20 +0000, Abhinav Jain wrote:
> Remove of_node_put from node_ctrl and node struct device_nodes.
> Move the declaration to initialization for ensuring scope sanity.
> 
> 

Applied to i2c/i2c-host on

git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux.git

Thank you,
Andi

Patches applied
===============
[1/1] i2c: mpc: Removal of of_node_put with __free for auto cleanup
      commit: 24e4a0d7c6b7a6491cc44781f3900129f56f447f

Re: [PATCH] i2c: mpc: Removal of of_node_put with __free for auto cleanup

[Michael Ellerman]

Chris Packham <Chris.Packham@alliedtelesis.co.nz> writes:
> On 16/04/24 08:54, Andi Shyti wrote:
>> Hi Abhinav,
>>
>>>   	/* Enable I2C interrupts for mpc5121 */
>>> -	node_ctrl = of_find_compatible_node(NULL, NULL,
>>> -					    "fsl,mpc5121-i2c-ctrl");
>>> +	struct device_node *node_ctrl __free(device_node) =
>> How have you tested this?
>
> I'm not sure I know anyone that still has a mpc5121. Maybe someone on 
> linuxppc-dev?

Not that I know of.

The driver loads on my T4240, but doesn't hit the right paths to test
this patch.

No objection to it being merged though.

cheers