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From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Sat, 10 Apr 2021 10:33:32 +0200
Message-ID: <CAMj1kXHTWf-9=y2kSVm09Ln9Aq=mriL57zEHwfBnS_K0Sqn86A@mail.gmail.com>
Subject: Re: [PATCH v2 1/1] efi/dev-path-parser: Switch to use for_each_acpi_dev_match()
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     linux-efi <linux-efi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Lukas Wunner <lukas@wunner.de>
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On Sun, 4 Apr 2021 at 20:12, Andy Shevchenko <andy.shevchenko@gmail.com> wrote:
>
> Switch to use for_each_acpi_dev_match() instead of home grown analogue.
> No functional change intended.
>
> Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> ---
> v2: fixed refcounting
>     (example from which I took the v1 approach has been broken, fix is sent :-)

Queued up in efi/next, thanks

>  drivers/firmware/efi/dev-path-parser.c | 49 ++++++++++----------------
>  1 file changed, 18 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/firmware/efi/dev-path-parser.c b/drivers/firmware/efi/dev-path-parser.c
> index 5c9625e552f4..10d4457417a4 100644
> --- a/drivers/firmware/efi/dev-path-parser.c
> +++ b/drivers/firmware/efi/dev-path-parser.c
> @@ -12,52 +12,39 @@
>  #include <linux/efi.h>
>  #include <linux/pci.h>
>
> -struct acpi_hid_uid {
> -       struct acpi_device_id hid[2];
> -       char uid[11]; /* UINT_MAX + null byte */
> -};
> -
> -static int __init match_acpi_dev(struct device *dev, const void *data)
> -{
> -       struct acpi_hid_uid hid_uid = *(const struct acpi_hid_uid *)data;
> -       struct acpi_device *adev = to_acpi_device(dev);
> -
> -       if (acpi_match_device_ids(adev, hid_uid.hid))
> -               return 0;
> -
> -       if (adev->pnp.unique_id)
> -               return !strcmp(adev->pnp.unique_id, hid_uid.uid);
> -       else
> -               return !strcmp("0", hid_uid.uid);
> -}
> -
>  static long __init parse_acpi_path(const struct efi_dev_path *node,
>                                    struct device *parent, struct device **child)
>  {
> -       struct acpi_hid_uid hid_uid = {};
> +       char hid[ACPI_ID_LEN], uid[11]; /* UINT_MAX + null byte */
> +       struct acpi_device *adev;
>         struct device *phys_dev;
>
>         if (node->header.length != 12)
>                 return -EINVAL;
>
> -       sprintf(hid_uid.hid[0].id, "%c%c%c%04X",
> +       sprintf(hid, "%c%c%c%04X",
>                 'A' + ((node->acpi.hid >> 10) & 0x1f) - 1,
>                 'A' + ((node->acpi.hid >>  5) & 0x1f) - 1,
>                 'A' + ((node->acpi.hid >>  0) & 0x1f) - 1,
>                         node->acpi.hid >> 16);
> -       sprintf(hid_uid.uid, "%u", node->acpi.uid);
> -
> -       *child = bus_find_device(&acpi_bus_type, NULL, &hid_uid,
> -                                match_acpi_dev);
> -       if (!*child)
> +       sprintf(uid, "%u", node->acpi.uid);
> +
> +       for_each_acpi_dev_match(adev, hid, NULL, -1) {
> +               if (adev->pnp.unique_id && !strcmp(adev->pnp.unique_id, uid))
> +                       break;
> +               if (!adev->pnp.unique_id && node->acpi.uid == 0)
> +                       break;
> +               acpi_dev_put(adev);
> +       }
> +       if (!adev)
>                 return -ENODEV;
>
> -       phys_dev = acpi_get_first_physical_node(to_acpi_device(*child));
> +       phys_dev = acpi_get_first_physical_node(adev);
>         if (phys_dev) {
> -               get_device(phys_dev);
> -               put_device(*child);
> -               *child = phys_dev;
> -       }
> +               *child = get_device(phys_dev);
> +               acpi_dev_put(adev);
> +       } else
> +               *child = &adev->dev;
>
>         return 0;
>  }
> --
> 2.31.1
>