Re: [PATCH] intel-hid: new hid event driver for hotkeys

[Andy Lutomirski <luto@amacapital.net>]

On Thu, Sep 29, 2016 at 9:02 AM, Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
> Quite a bit late, but still:
>
> On Wed, Dec 16, 2015 at 11:30 PM, Alex Hung <alex.hung@canonical.com> wrote:
>> +
>> +static int __init intel_hid_init(void)
>> +{
>> +       acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
>> +                           ACPI_UINT32_MAX, check_acpi_dev, NULL,
>> +                           (void *)intel_hid_ids, NULL);
>> +
>> +       return platform_driver_register(&intel_hid_pl_driver);
>> +}
>
> Why do we need to walk instantiate the device ourselves instead of
> having ACPI core do it for us? I also see this pattern in intel-vbtn.c
> now.

See the comment above check_acpi_dev():

/*
 * Unfortunately, some laptops provide a _HID="INT33D5" device with
 * _CID="PNP0C02".  This causes the pnpacpi scan driver to claim the
 * ACPI node, so no platform device will be created.  The pnpacpi
 * driver rejects this device in subsequent processing, so no physical
 * node is created at all.
 *
 * As a workaround until the ACPI core figures out how to handle
 * this corner case, manually ask the ACPI platform device code to
 * claim the ACPI node.
 */


>
> Thanks.
>
> --
> Dmitry



-- 
Andy Lutomirski
AMA Capital Management, LLC