Re: [PATCH v4] HID: i2c-hid: Refactor _DSM helper and add i2c-hid-acpi-prp0001 driver

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Using `of_match_ptr()` on the `of_match_table` prevents native ACPI PRP0001 matching when `CONFIG_OF` is disabled.
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commit fdffe866c804a579c14dbd7b1c8529b20466017b
Author: 谢致邦 (XIE Zhibang) <Yeking@Red54.com>

HID: i2c-hid: Refactor _DSM helper and add i2c-hid-acpi-prp0001 driver

This commit moves the _DSM call that retrieves the HID descriptor address into
a shared header. It also introduces the i2c-hid-acpi-prp0001 driver to handle
devices with _HID "PRP0001" and _DSD compatible "hid-over-i2c" that are missing
the "hid-descr-addr" property.

> diff --git a/drivers/hid/i2c-hid/i2c-hid-acpi-prp0001.c b/drivers/hid/i2c-hid/i2c-hid-acpi-prp0001.c
> new file mode 100644
> --- /dev/null
> +++ b/drivers/hid/i2c-hid/i2c-hid-acpi-prp0001.c

[ ... ]

> +static const struct of_device_id i2c_hid_acpi_prp0001_of_match[] = {
> +	{ .compatible = "hid-over-i2c" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, i2c_hid_acpi_prp0001_of_match);
> +

[ ... ]

> +static struct i2c_driver i2c_hid_acpi_prp0001_driver = {
> +	.driver = {
> +		.name	= "i2c_hid_acpi_prp0001",
> +		.pm	= &i2c_hid_core_pm,
> +		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
> +		.of_match_table = of_match_ptr(i2c_hid_acpi_prp0001_of_match),

[Severity: High]
Will this prevent the driver from probing on ACPI systems that do not enable
CONFIG_OF?

The driver relies on ACPI PRP0001 matching to match the _DSD compatible
property against the of_match_table. However, if CONFIG_OF is disabled
(which is standard for x86 ACPI platforms where this hardware exists),
of_match_ptr() evaluates to NULL.

When of_match_table is NULL, the ACPI driver core will silently fail to
match the device, leaving the touchpad non-functional. Should we drop the
of_match_ptr() wrapper here to ensure the table is always available for
PRP0001 matching?

> +	},
> +
> +	.probe		= i2c_hid_acpi_prp0001_probe,
> +	.remove		= i2c_hid_core_remove,
> +	.shutdown	= i2c_hid_core_shutdown,
> +	.id_table	= i2c_hid_acpi_prp0001_id,
> +};

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Sashiko AI review · https://sashiko.dev/#/patchset/tencent_6169D37BDAAD7FFEEC9E41DA197FE6028309@qq.com?part=1