Re: [PATCH 11/23] i2c: pxa-pci: use platform_device_set_of_node()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] OF node reference leak when replacing direct assignment with platform_device_set_of_node().
--

commit 97e00c5939b668c9a126c1fc7447ee82d933bd92
Author: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

i2c: pxa-pci: use platform_device_set_of_node()
    
Ahead of reworking the reference counting logic for platform devices,
encapsulate the assignment of the OF node for dynamically allocated
platform devices with the provided helper.

> diff --git a/drivers/i2c/busses/i2c-pxa-pci.c b/drivers/i2c/busses/i2c-pxa-pci.c
> index dbd542300f800..92a0647f08c69 100644
> --- a/drivers/i2c/busses/i2c-pxa-pci.c
> +++ b/drivers/i2c/busses/i2c-pxa-pci.c

[ ... ]

> @@ -76,7 +76,8 @@ static struct platform_device *add_i2c_device(struct pci_dev *dev, int bar)
>  		goto out;
>  	}
>  	pdev->dev.parent = &dev->dev;
> -	pdev->dev.of_node = child;
> +
> +	platform_device_set_of_node(pdev, child);

[Severity: Medium]
Does this change result in an OF node reference leak?

Earlier in add_i2c_device(), the child node is acquired by breaking out of a
for_each_child_of_node loop, which holds a reference to the node:

	for_each_child_of_node(dev->dev.of_node, child) {
		...
		break;
	}

Previously, assigning pdev->dev.of_node = child implicitly transferred this
reference to the platform device, which would eventually be released during
device cleanup. 

However, platform_device_set_of_node explicitly acquires an additional
reference via of_node_get:

drivers/base/platform.c:platform_device_set_of_node() {
	...
	pdev->dev.of_node = of_node_get(np);
	...
}

Because the helper now manages its own reference, the original reference
held by the local child variable appears to be unconsumed. Should there
be an explicit of_node_put(child) called after platform_device_set_of_node
to prevent a leak?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260521-pdev-fwnode-ref-v1-0-88c324a1b8d2@oss.qualcomm.com?part=11