Re: [PATCH] HID: uclogic: make input_mapping independent of usb

[Nikolai Kondrashov <spbnick@gmail.com>]

On 03/13/2015 05:42 PM, Benjamin Tissoires wrote:
> No need to retrieve the USB handle in input_mapping() when we already
> do that in probe. It also allows to use the quirk without having to
> add the product ID matching.
>
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
> ---
>
> Nick,
>
> no need to cc DIGImend-devel when replying on this one, I'll send the same
> to DIGImend-devel as soon as I have a patchwork link.
>
> Cheers,
> Benjamin
>
>   drivers/hid/hid-uclogic.c | 17 ++++++++---------
>   1 file changed, 8 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/hid/hid-uclogic.c b/drivers/hid/hid-uclogic.c
> index bdda9fd..6473e83 100644
> --- a/drivers/hid/hid-uclogic.c
> +++ b/drivers/hid/hid-uclogic.c
> @@ -627,6 +627,7 @@ struct uclogic_drvdata {
>   	__u8 *rdesc;
>   	unsigned int rsize;
>   	bool invert_pen_inrange;
> +	bool ignore_pen_interface;
>   };
>
>   static __u8 *uclogic_report_fixup(struct hid_device *hdev, __u8 *rdesc,
> @@ -719,16 +720,12 @@ static int uclogic_input_mapping(struct hid_device *hdev, struct hid_input *hi,
>   		struct hid_field *field, struct hid_usage *usage,
>   		unsigned long **bit, int *max)
>   {
> -	struct usb_interface *intf;
> -
> -	if (hdev->product == USB_DEVICE_ID_HUION_TABLET) {
> -		intf = to_usb_interface(hdev->dev.parent);
> +	struct uclogic_drvdata *drvdata = hid_get_drvdata(hdev);
>
> -		/* discard the unused pen interface */
> -		if ((intf->cur_altsetting->desc.bInterfaceNumber != 0) &&
> -		    (field->application == HID_DG_PEN))
> -			return -1;
> -	}
> +	/* discard the unused pen interface */
> +	if ((drvdata->ignore_pen_interface) &&
> +	    (field->application == HID_DG_PEN))
> +		return -1;
>
>   	/* let hid-core decide what to do */
>   	return 0;
> @@ -908,6 +905,8 @@ static int uclogic_probe(struct hid_device *hdev,
>   				return rc;
>   			}
>   			drvdata->invert_pen_inrange = true;
> +		} else {
> +			drvdata->ignore_pen_interface = true;
>   		}
>   		break;
>   	}

This looks fine to me logically, but the "ignore_pen_interface" name is a bit
confusing.

 From the driver code and comments it follows that "pen interface" is the USB
interface #0 and we're not ignoring it (uclogic_probe code becomes the worst
here).  I think that it is better to call it in terms of what the
"input_mapping" description says, i.e. "ignore_pen_usage".

Nick