Re: [PATCH v9 4/7] input: keyboard: Add driver for ASUS Transformer dock multimedia keys

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Explicitly calling `input_unregister_device()` on a device allocated with `devm_input_allocate_device()`.
--

commit b1b4cf8c044b790c2019bf0bb44a52ad2de52358
Author: Michał Mirosław <mirq-linux@rere.qmqm.pl>

input: keyboard: Add driver for ASUS Transformer dock multimedia keys

This patch adds support for the multimedia top button row of the ASUS
Transformer's Mobile Dock keyboard. It tracks keyboard input events for
AltGr presses to switch to multimedia keys.

> diff --git a/drivers/input/keyboard/asus-transformer-ec-keys.c b/drivers/input/keyboard/asus-transformer-ec-keys.c
> new file mode 100644
> index 0000000000000..53aff3ce7146d
> --- /dev/null
> +++ b/drivers/input/keyboard/asus-transformer-ec-keys.c

[ ... ]

> +static int asus_ec_keys_probe(struct platform_device *pdev)
> +{
> +	struct i2c_client *parent = to_i2c_client(pdev->dev.parent);
> +	struct asusec_core *ec = dev_get_drvdata(pdev->dev.parent);
> +	struct device *dev = &pdev->dev;
> +	struct asus_ec_keys_data *priv;
> +	int error;
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, priv);
> +	priv->ec = ec;
> +
> +	priv->xidev = devm_input_allocate_device(dev);

[ ... ]

> +	error = input_register_device(priv->xidev);
> +	if (error)
> +		return dev_err_probe(dev, error,
> +				     "failed to register extension keys\n");
> +
> +	error = asus_ec_keys_register_handler(dev, priv);
> +	if (error) {
> +		input_unregister_device(priv->xidev);

[Severity: Medium]
Since priv->xidev is allocated with devm_input_allocate_device() earlier in
asus_ec_keys_probe(), does explicitly calling input_unregister_device()
here in the error path lead to a double-unregistration when the managed API
automatic cleanup triggers?

> +		return error;
> +	}
> +
> +	priv->nb.notifier_call = asus_ec_keys_notify;
> +
> +	error = blocking_notifier_chain_register(&ec->notify_list, &priv->nb);
> +	if (error) {
> +		input_unregister_device(priv->xidev);

[Severity: Medium]
Could manually unregistering the devm-managed input device here in the
notifier registration error path similarly cause a double-unregistration?

> +		input_unregister_handler(&priv->input_handler);
> +		return error;
> +	}
> +
> +	return 0;
> +}
> +
> +static void asus_ec_keys_remove(struct platform_device *pdev)
> +{
> +	struct asus_ec_keys_data *priv = platform_get_drvdata(pdev);
> +	struct asusec_core *ec = priv->ec;
> +
> +	blocking_notifier_chain_unregister(&ec->notify_list, &priv->nb);
> +	input_unregister_handler(&priv->input_handler);
> +	input_unregister_device(priv->xidev);

[Severity: Medium]
Does bypassing the automatic devm lifecycle by explicitly calling
input_unregister_device() in asus_ec_keys_remove() on a managed device lead
to double-unregistration when the device is unbound?

> +}

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260625081529.22447-1-clamor95@gmail.com?part=4