# Re: \[PATCHv4 2/5\] HID: hid-input: Add suffix also for HID\_DG\_PEN

- From: Benjamin Tissoires \<hidden\>
- Date: 2021-12-10 16:21:32 
- List: linux-input
- Page: https://ratatoskr.run/linux-input/2021/12/1604017
- Thread: https://ratatoskr.run/linux-input/2021/12/1603689/t.md

```text


On Fri, Dec 10, 2021 at 12:12 PM Tero Kristo [ref] wrote:
>
> From: Mika Westerberg <mika.westerberg@linux.intel.com>
>
> This and HID_DG_STYLUS are pretty much the same thing so add suffix for
> HID_DG_PEN too. This makes the input device name look better.
>
> While doing this, remove the suffix override from hid-multitouch, as it
> is now handled by hid-input. Also, the suffix override done by
> hid-multitouch was wrong, as it mapped HID_DG_PEN => "Stylus" and
> HID_DG_STYLUS => "Pen".

FWIW, I was thinking at the following:
---
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 837585f4e673..fe0da7bf24a9 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -1775,6 +1775,15 @@ static struct hid_input *hidinput_allocate(struct hid_device *hid,
                        suffix = "Mouse";
                        break;
                case HID_DG_PEN:
+                       /*
+                        * yes, there is an issue here:
+                        *  DG_PEN -> "Stylus"
+                        *  DG_STYLUS -> "Pen"
+                        * But changing this now means users with config snippets
+                        * will have to change it and the test suite will not be happy.
+                        */
+                       suffix = "Stylus";
+                       break;
                case HID_DG_STYLUS:
                        suffix = "Pen";
                        break;
---

Because the current patch breaks the test suite.

Cheers,
Benjamin

>
> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> Signed-off-by: Tero Kristo <redacted>
> ---
>  drivers/hid/hid-input.c      | 1 +
>  drivers/hid/hid-multitouch.c | 3 ---
>  2 files changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
> index ad718ceb8af3..78205e445652 100644
> --- a/drivers/hid/hid-input.c
> +++ b/drivers/hid/hid-input.c
> @@ -1741,6 +1741,7 @@ static struct hid_input *hidinput_allocate(struct hid_device *hid,
>                 case HID_GD_MOUSE:
>                         suffix = "Mouse";
>                         break;
> +               case HID_DG_PEN:
>                 case HID_DG_STYLUS:
>                         suffix = "Pen";
>                         break;
> diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
> index 082376a6cb3d..99eabfb4145b 100644
> --- a/drivers/hid/hid-multitouch.c
> +++ b/drivers/hid/hid-multitouch.c
> @@ -1606,9 +1606,6 @@ static int mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
>         case HID_DG_STYLUS:
>                 /* force BTN_STYLUS to allow tablet matching in udev */
>                 __set_bit(BTN_STYLUS, hi->input->keybit);
> -               fallthrough;
> -       case HID_DG_PEN:
> -               suffix = "Stylus";
>                 break;
>         default:
>                 suffix = "UNKNOWN";
> --
> 2.25.1
>

```