Commit 042628ab authored by Jason Gerecke's avatar Jason Gerecke Committed by Jiri Kosina
Browse files

HID: wacom: Discover device_type from HID descriptor for all devices 



Currently, we assume a device_type of BTN_TOOL_PEN before scanning the
HID descriptor and then change the device_type if what we discover
proves that assumption wrong. This way of doing things makes it more
difficult to figure out if a device (particularly a HID_GENERIC device)
actually does tablet/touch input or is something completley different.

This patch leaves device_type at its initial value of 0 and then calls
'wacom_parse_hid' for every device (not just those that have touch).
As we map the usages, we can set the device_type as before. After we're
finished, we can then check if the value is still zero and do whatever
is most appropriate.

Detecting the pen can be a little tricky on most Wacom devices because
the descriptors describe opaque blobs. Fortunately, older Wacom tablets
have the HID_DG_DIGITIZER usage on the pen's application collection and
newer tablets seem to have a similar vendor-defined usage that we can
trigger on.

Signed-off-by: default avatarJason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: default avatarPing Cheng <pingc@wacom.com>
Reviewed-by: default avatarBenjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent 8d80f790

drivers/hid/wacom_sys.c

+13 −10
Original line number Diff line number Diff line
@@ -181,7 +181,11 @@ static void wacom_usage_mapping(struct hid_device *hdev, 
	* X/Y values and some cases of invalid Digitizer X/Y

	* values commonly reported.

	*/

	if (!pen && !finger)

	if (pen)

		features->device_type = BTN_TOOL_PEN;

	else if (finger)

		features->device_type = BTN_TOOL_FINGER;

	else

		return;



	/*
@@ -198,14 +202,11 @@ static void wacom_usage_mapping(struct hid_device *hdev, 
	case HID_GD_X:

		features->x_max = field->logical_maximum;

		if (finger) {

			features->device_type = BTN_TOOL_FINGER;

			features->x_phy = field->physical_maximum;

			if (features->type != BAMBOO_PT) {

				features->unit = field->unit;

				features->unitExpo = field->unit_exponent;

			}

		} else {

			features->device_type = BTN_TOOL_PEN;

		}

		break;

	case HID_GD_Y:
@@ -425,7 +426,6 @@ static void wacom_retrieve_hid_descriptor(struct hid_device *hdev, 
	struct usb_interface *intf = wacom->intf;



	/* default features */

	features->device_type = BTN_TOOL_PEN;

	features->x_fuzz = 4;

	features->y_fuzz = 4;

	features->pressure_fuzz = 0;
@@ -446,10 +446,6 @@ static void wacom_retrieve_hid_descriptor(struct hid_device *hdev, 
		}

	}



	/* only devices that support touch need to retrieve the info */

	if (features->type < BAMBOO_PT)

		return;



	wacom_parse_hid(hdev, features);

}
@@ -1529,8 +1525,15 @@ static int wacom_probe(struct hid_device *hdev, 


	/* Retrieve the physical and logical size for touch devices */

	wacom_retrieve_hid_descriptor(hdev, features);



	wacom_setup_device_quirks(wacom);



	if (!features->device_type && features->type != WIRELESS) {

		dev_warn(&hdev->dev, "Unknown device_type for '%s'. %s.",

			 hdev->name, "Assuming pen");



		features->device_type = BTN_TOOL_PEN;

	}



	wacom_calculate_res(features);



	wacom_update_name(wacom);

drivers/hid/wacom_wac.c

+5 −3
Original line number Diff line number Diff line
@@ -2186,13 +2186,15 @@ void wacom_setup_device_quirks(struct wacom *wacom) 


			features->x_max = 4096;

			features->y_max = 4096;

		} else {

			features->device_type = BTN_TOOL_PEN;

		}

	}



	/*

	 * Same thing for Bamboo PAD

	 * Raw Wacom-mode pen and touch events both come from interface

	 * 0, whose HID descriptor has an application usage of 0xFF0D

	 * (i.e., WACOM_VENDORDEFINED_PEN). We route pen packets back

	 * out through the HID_GENERIC device created for interface 1,

	 * so rewrite this one to be of type BTN_TOOL_FINGER.

	 */

	if (features->type == BAMBOO_PAD)

		features->device_type = BTN_TOOL_FINGER;

drivers/hid/wacom_wac.h

+5 −1
Original line number Diff line number Diff line
@@ -72,10 +72,14 @@ 
#define WACOM_QUIRK_MONITOR		0x0004

#define WACOM_QUIRK_BATTERY		0x0008



#define WACOM_VENDORDEFINED_PEN		0xff0d0001



#define WACOM_PEN_FIELD(f)	(((f)->logical == HID_DG_STYLUS) || \

				 ((f)->physical == HID_DG_STYLUS) || \

				 ((f)->physical == HID_DG_PEN) || \

				 ((f)->application == HID_DG_PEN))

				 ((f)->application == HID_DG_PEN) || \

				 ((f)->application == HID_DG_DIGITIZER) || \

				 ((f)->application == WACOM_VENDORDEFINED_PEN))

#define WACOM_FINGER_FIELD(f)	(((f)->logical == HID_DG_FINGER) || \

				 ((f)->physical == HID_DG_FINGER) || \

				 ((f)->application == HID_DG_TOUCHSCREEN))

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