Re: [PATCH 2/2] HID: huion: split the stylus and pad in 2 nodes

[Nikolai Kondrashov <spbnick@gmail.com>]

On 02/18/2015 12:54 AM, Benjamin Tissoires wrote:
> Libinput expects the pad node to be different from the stylus one.
> We can just use HID_QUIRK_MULTI_INPUT to separate the buttons of the
> pad than the actual stylus.
> We can also remove the unused interfaces.
> Last, we append "Pen" or "Pad" suffix to the appropriate input node
> to match what the Wacom driver does and be more convenient for the users
> to know which one is which.

This is very nice and a thing that users asked for and I wanted to add for a
long while. I overlooked the addition of the input_configured callback
support.

>
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
> ---
>   drivers/hid/hid-huion.c | 31 +++++++++++++++++++++++++++++++
>   1 file changed, 31 insertions(+)
>
> diff --git a/drivers/hid/hid-huion.c b/drivers/hid/hid-huion.c
> index 50fbda4..f298f66 100644
> --- a/drivers/hid/hid-huion.c
> +++ b/drivers/hid/hid-huion.c
> @@ -142,6 +142,33 @@ static __u8 *huion_report_fixup(struct hid_device *hdev, __u8 *rdesc,
>   	return rdesc;
>   }
>
> +static void huion_input_configured(struct hid_device *hdev,
> +		struct hid_input *hi)
> +{
> +	char *name;
> +	const char *suffix = NULL;
> +	struct hid_field *field = hi->report->field[0];
> +
> +	switch (field->application) {
> +	case HID_GD_KEYPAD:
> +		suffix = "Pad";
> +		break;
> +	case HID_DG_PEN:
> +		suffix = "Pen";
> +		break;
> +	}
> +
> +	if (suffix) {
> +		name = devm_kzalloc(&hi->input->dev,
> +				    strlen(hdev->name) + strlen(suffix) + 2,
> +				    GFP_KERNEL);
> +		if (name) {
> +			sprintf(name, "%s %s", hdev->name, suffix);

I would have preferred an snprintf here instead, with the buffer length
calculated once and specified explicitly.

> +			hi->input->name = name;
> +		}
> +	}
> +}
> +
>   /**
>    * Enable fully-functional tablet mode and determine device parameters.
>    *
> @@ -282,6 +309,9 @@ static int huion_probe(struct hid_device *hdev, const struct hid_device_id *id)
>   				hid_err(hdev, "tablet enabling failed\n");
>   				return rc;
>   			}
> +			hdev->quirks |= HID_QUIRK_MULTI_INPUT;
> +		} else {
> +			return -ENODEV;
>   		}
>   		break;
>   	}
> @@ -335,6 +365,7 @@ static struct hid_driver huion_driver = {
>   	.probe = huion_probe,
>   	.report_fixup = huion_report_fixup,
>   	.raw_event = huion_raw_event,
> +	.input_configured = huion_input_configured,
>   };
>   module_hid_driver(huion_driver);
>
>

Thanks, Benjamin!

Nick