[PATCH libinput] udev: check wacom devices for a paired product id

[Peter Hutterer]

The newer Wacom Cintiqs have touch devices with a different PID than the pen
device. Use the new libwacom_get_paired_device call where available to pair
the two devices and give them the same device group.

This isn't that important just yet, so no need to force users to update to a
new libwacom version.

Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
Tested-by: Benjamin Tissoires <benjamin.tissoires at gmail.com>
---
 configure.ac                 |  9 +++++++
 udev/Makefile.am             |  5 ++++
 udev/libinput-device-group.c | 62 ++++++++++++++++++++++++++++++++++++++++++--
 3 files changed, 74 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 9e238b4..1bf912e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -208,7 +208,16 @@ AC_ARG_ENABLE(libwacom,
 if test "x$use_libwacom" = "xyes"; then
 	PKG_CHECK_MODULES(LIBWACOM, [libwacom >= 0.12], [HAVE_LIBWACOM="yes"])
 	AC_DEFINE(HAVE_LIBWACOM, 1, [Build with libwacom])
+	AC_CHECK_LIB([wacom],
+		     [libwacom_get_paired_device],
+		     [libwacom_have_get_paired_device=yes,
+		      AC_DEFINE(HAVE_LIBWACOM_GET_PAIRED_DEVICE, [1],
+				[libwacom_get_paired_device() is available])],
+		     [libwacom_have_get_paired_device=no],
+		     [$LIBWACOM_LIBS])
 fi
+AM_CONDITIONAL(HAVE_LIBWACOM_GET_PAIRED_DEVICE,
+	       [test "x$libwacom_get_paired_device" == "xyes"])
 
 AM_CONDITIONAL(HAVE_VALGRIND, [test "x$VALGRIND" != "x"])
 AM_CONDITIONAL(BUILD_TESTS, [test "x$build_tests" = "xyes"])
diff --git a/udev/Makefile.am b/udev/Makefile.am
index cfb854e..78e3791 100644
--- a/udev/Makefile.am
+++ b/udev/Makefile.am
@@ -10,6 +10,11 @@ libinput_device_group_SOURCES = libinput-device-group.c
 libinput_device_group_CFLAGS = $(LIBUDEV_CFLAGS) $(GCC_CFLAGS)
 libinput_device_group_LDADD = $(LIBUDEV_LIBS)
 
+if HAVE_LIBWACOM_GET_PAIRED_DEVICE
+libinput_device_group_CFLAGS += $(LIBWACOM_CFLAGS)
+libinput_device_group_LDADD += $(LIBWACOM_LIBS)
+endif
+
 libinput_model_quirks_SOURCES = libinput-model-quirks.c
 libinput_model_quirks_CFLAGS = \
 			       -I$(top_srcdir)/src \
diff --git a/udev/libinput-device-group.c b/udev/libinput-device-group.c
index ab9409b..217ed44 100644
--- a/udev/libinput-device-group.c
+++ b/udev/libinput-device-group.c
@@ -21,11 +21,47 @@
  * DEALINGS IN THE SOFTWARE.
  */
 
+#include "config.h"
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <libudev.h>
 
+#if HAVE_LIBWACOM_GET_PAIRED_DEVICE
+#include <libwacom/libwacom.h>
+
+static void
+wacom_handle_paired(struct udev_device *device,
+		    int *vendor_id,
+		    int *product_id)
+{
+	WacomDeviceDatabase *db = NULL;
+	WacomDevice *tablet = NULL;
+	const WacomMatch *paired;
+
+	db = libwacom_database_new();
+	if (!db)
+		goto out;
+
+	tablet = libwacom_new_from_usbid(db, *vendor_id, *product_id, NULL);
+	if (!tablet)
+		goto out;
+	paired = libwacom_get_paired_device(tablet);
+	if (!paired)
+		goto out;
+
+	*vendor_id = libwacom_match_get_vendor_id(paired);
+	*product_id = libwacom_match_get_product_id(paired);
+
+out:
+	if (tablet)
+		libwacom_destroy(tablet);
+	if (db)
+		libwacom_database_destroy(db);
+}
+#endif
+
 int main(int argc, char **argv)
 {
 	int rc = 1;
@@ -34,6 +70,7 @@ int main(int argc, char **argv)
 	const char *syspath,
 	           *phys = NULL;
 	const char *product;
+	int bustype, vendor_id, product_id, version;
 	char group[1024];
 	char *str;
 
@@ -73,8 +110,29 @@ int main(int argc, char **argv)
 	   on that*/
 	product = udev_device_get_property_value(device, "PRODUCT");
 	if (!product)
-		product = "";
-	snprintf(group, sizeof(group), "%s:%s", product, phys);
+		product = "00/00/00/00";
+
+	if (sscanf(product,
+		   "%x/%x/%x/%x",
+		   &bustype,
+		   &vendor_id,
+		   &product_id,
+		   &version) != 4) {
+		snprintf(group, sizeof(group), "%s:%s", product, phys);
+	} else {
+#if HAVE_LIBWACOM_GET_PAIRED_DEVICE
+	    if (vendor_id == VENDOR_ID_WACOM)
+		    wacom_handle_paired(device, &vendor_id, &product_id);
+#endif
+	    snprintf(group,
+		     sizeof(group),
+		     "%x/%x/%x/%x:%s",
+		     bustype,
+		     vendor_id,
+		     product_id,
+		     version,
+		     phys);
+	}
 
 	str = strstr(group, "/input");
 	if (str)
-- 
2.7.4