Re: [PATCH v3] HID: apple: Properly handle function keys on non-Apple keyboard

[Bryan Cain]

I can't reply to v4 since I wasn't cc'd on that one and I'm not subscribed to
the mailing list, but while I haven't tested it yet, it looks good.

The only feedback I have is that according to my searching[1][2][3], Varmilo
keyboards pretending to be Apple devices report themselves as "AONE Varmilo
Keyboard", so it might be a good idea to add "AONE" to the list of clone
vendors.

Regards,
Bryan

[1] https://geekhack.org/index.php?topic=110250.msg3013629#msg3013629
[2] https://www.mail-archive.com/debian-bugs-dist@xxxxxxxxxxxxxxxx/msg1750654.html
[3] https://forums.servethehome.com/index.php?threads/varmilo-keyboard-fn-keys-under-linux.29041/

On Tue, May 31, 2022 at 5:27 PM Hilton Chain <hako@ultrarare.space> wrote:
>
> This commit extends fa33382c7f74 ("HID: apple: Properly handle function
> keys on Keychron keyboards") by adding an array of known non-Apple
> keyboards' device names, and the function apple_is_non_apple_keyboard()
> to identify and create exception for them.
>
> Signed-off-by: Hilton Chain <hako@ultrarare.space>
> ---
>  drivers/hid/hid-apple.c | 33 ++++++++++++++++++++++++++++-----
>  1 file changed, 28 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/hid/hid-apple.c b/drivers/hid/hid-apple.c
> index 42a568902f49..7d56530d9e3a 100644
> --- a/drivers/hid/hid-apple.c
> +++ b/drivers/hid/hid-apple.c
> @@ -36,7 +36,7 @@
>  #define APPLE_NUMLOCK_EMULATION        BIT(8)
>  #define APPLE_RDESC_BATTERY    BIT(9)
>  #define APPLE_BACKLIGHT_CTL    BIT(10)
> -#define APPLE_IS_KEYCHRON      BIT(11)
> +#define APPLE_IS_NON_APPLE     BIT(11)
>
>  #define APPLE_FLAG_FKEY                0x01
>
> @@ -65,6 +65,10 @@ MODULE_PARM_DESC(swap_fn_leftctrl, "Swap the Fn and left Control keys. "
>                 "(For people who want to keep PC keyboard muscle memory. "
>                 "[0] = as-is, Mac layout, 1 = swapped, PC layout)");
>
> +struct apple_non_apple_keyboard {
> +       char *name;
> +};
> +
>  struct apple_sc_backlight {
>         struct led_classdev cdev;
>         struct hid_device *hdev;
> @@ -313,6 +317,25 @@ static const struct apple_key_translation swapped_fn_leftctrl_keys[] = {
>         { }
>  };
>
> +static const struct apple_non_apple_keyboard non_apple_keyboards[] = {
> +       { "SONiX USB DEVICE" },
> +       { "Keychron" },
> +};
> +
> +static bool apple_is_non_apple_keyboard(struct hid_device *hdev)
> +{
> +       int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(non_apple_keyboards); i++) {
> +               char *non_apple = non_apple_keyboards[i].name;
> +
> +               if (strlen(non_apple) && strncmp(hdev->name, non_apple, strlen(non_apple)) == 0)
> +                       return true;
> +       }
> +
> +       return false;
> +}
> +
>  static inline void apple_setup_key_translation(struct input_dev *input,
>                 const struct apple_key_translation *table)
>  {
> @@ -363,7 +386,7 @@ static int hidinput_apple_event(struct hid_device *hid, struct input_dev *input,
>         }
>
>         if (fnmode == 3) {
> -               real_fnmode = (asc->quirks & APPLE_IS_KEYCHRON) ? 2 : 1;
> +               real_fnmode = (asc->quirks & APPLE_IS_NON_APPLE) ? 2 : 1;
>         } else {
>                 real_fnmode = fnmode;
>         }
> @@ -669,9 +692,9 @@ static int apple_input_configured(struct hid_device *hdev,
>                 asc->quirks &= ~APPLE_HAS_FN;
>         }
>
> -       if (strncmp(hdev->name, "Keychron", 8) == 0) {
> -               hid_info(hdev, "Keychron keyboard detected; function keys will default to fnmode=2 behavior\n");
> -               asc->quirks |= APPLE_IS_KEYCHRON;
> +       if (apple_is_non_apple_keyboard(hdev)) {
> +               hid_info(hdev, "Non-apple keyboard detected; function keys will default to fnmode=2 behavior\n");
> +               asc->quirks |= APPLE_IS_NON_APPLE;
>         }
>
>         return 0;
>
> base-commit: e1cbc3b96a9974746b2a80c3a6c8a0f7eff7b1b5
> --
> 2.36.1
>