pad: Add a new API for modes and mode groups

Move mode control to libinput. This reduces some flexibility on what we can do
with modes but makes it a lot easier for anyone to implement modes correctly
and have the LEDs apply appropriately, etc. Let's go with the option to make
the 95% use-case easy. Note: whether the mode is actually used is up to the
caller, e.g.  under Windows and OS X the mode only applies to the
rings/strips, not the buttons.

A tablet pad has 1 or more mode groups, all buttons/ring/strips are assigned
to a mode group. That group has a numeric mode index and is hooked to the
LEDs. libinput will switch the LEDs accordingly.

The mode group is a separate object. This allows for better APIs when it comes
to:
* checking whether a button/ring/strip is part of a mode group
* checking whether a button will trigger a mode transition

and in the future potentially:
* checking which mode transition will happen
* setting which button should change the mode transition
* changing what type of mode transition should happen.
* moving a button from one mode group to the other

This patch adds the basic scaffolding, without any real implementation.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Proofread-by: Yong Bakos <ybakos@humanoriented.com>
Reviewed-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Carlos Garnacho <carlosg@gnome.org>

2 files changed, 52 insertions, 10 deletions

diff --git a/tools/event-debug.c b/tools/event-debug.c
index a5608d2b..70f4268f 100644
--- a/tools/event-debug.c
+++ b/tools/event-debug.c
@@ -130,6 +130,9 @@ print_event_header(struct libinput_event *ev)
 	case LIBINPUT_EVENT_TABLET_PAD_STRIP:
 		type = "TABLET_PAD_STRIP";
 		break;
+	case LIBINPUT_EVENT_TABLET_PAD_MODE:
+		type = "TABLET_PAD_MODE";
+		break;
 	}
 
 	printf("%-7s	%-16s ", libinput_device_get_sysname(dev), type);
@@ -232,16 +235,18 @@ print_device_notify(struct libinput_event *ev)
 
 	if (libinput_device_has_capability(dev,
 					   LIBINPUT_DEVICE_CAP_TABLET_PAD)) {
-		int nbuttons, nstrips, nrings;
+		int nbuttons, nstrips, nrings, ngroups;
 
 		nbuttons = libinput_device_tablet_pad_get_num_buttons(dev);
 		nstrips = libinput_device_tablet_pad_get_num_strips(dev);
 		nrings = libinput_device_tablet_pad_get_num_rings(dev);
+		ngroups = libinput_device_tablet_pad_get_num_mode_groups(dev);
 
-		printf(" buttons:%d strips:%d rings:%d",
+		printf(" buttons:%d strips:%d rings:%d mode groups:%d",
 		       nbuttons,
 		       nstrips,
-		       nrings);
+		       nrings,
+		       ngroups);
 	}
 
 	printf("\n");
@@ -604,14 +609,25 @@ static void
 print_tablet_pad_button_event(struct libinput_event *ev)
 {
 	struct libinput_event_tablet_pad *p = libinput_event_get_tablet_pad_event(ev);
+	struct libinput_tablet_pad_mode_group *group;
 	enum libinput_button_state state;
+	unsigned int button, mode;
 
 	print_event_time(libinput_event_tablet_pad_get_time(p));
 
+	button = libinput_event_tablet_pad_get_button_number(p),
 	state = libinput_event_tablet_pad_get_button_state(p);
-	printf("%3d %s\n",
-	       libinput_event_tablet_pad_get_button_number(p),
-	       state == LIBINPUT_BUTTON_STATE_PRESSED ? "pressed" : "released");
+	mode = libinput_event_tablet_pad_get_mode(p);
+	printf("%3d %s (mode %d)",
+	       button,
+	       state == LIBINPUT_BUTTON_STATE_PRESSED ? "pressed" : "released",
+	       mode);
+
+	group = libinput_event_tablet_pad_get_mode_group(p);
+	if (libinput_tablet_pad_mode_group_button_is_toggle(group, button))
+		printf(" <mode toggle>");
+
+	printf("\n");
 }
 
 static void
@@ -619,6 +635,7 @@ print_tablet_pad_ring_event(struct libinput_event *ev)
 {
 	struct libinput_event_tablet_pad *p = libinput_event_get_tablet_pad_event(ev);
 	const char *source = "<invalid>";
+	unsigned int mode;
 
 	print_event_time(libinput_event_tablet_pad_get_time(p));
 
@@ -631,10 +648,12 @@ print_tablet_pad_ring_event(struct libinput_event *ev)
 		break;
 	}
 
-	printf("ring %d position %.2f (source %s)\n",
+	mode = libinput_event_tablet_pad_get_mode(p);
+	printf("ring %d position %.2f (source %s) (mode %d)\n",
 	       libinput_event_tablet_pad_get_ring_number(p),
 	       libinput_event_tablet_pad_get_ring_position(p),
-	       source);
+	       source,
+	       mode);
 }
 
 static void
@@ -642,6 +661,7 @@ print_tablet_pad_strip_event(struct libinput_event *ev)
 {
 	struct libinput_event_tablet_pad *p = libinput_event_get_tablet_pad_event(ev);
 	const char *source = "<invalid>";
+	unsigned int mode;
 
 	print_event_time(libinput_event_tablet_pad_get_time(p));
 
@@ -654,10 +674,28 @@ print_tablet_pad_strip_event(struct libinput_event *ev)
 		break;
 	}
 
-	printf("strip %d position %.2f (source %s)\n",
+	mode = libinput_event_tablet_pad_get_mode(p);
+	printf("strip %d position %.2f (source %s) (mode %d)\n",
 	       libinput_event_tablet_pad_get_strip_number(p),
 	       libinput_event_tablet_pad_get_strip_position(p),
-	       source);
+	       source,
+	       mode);
+}
+
+static void
+print_tablet_pad_mode_event(struct libinput_event *ev)
+{
+	struct libinput_event_tablet_pad *p = libinput_event_get_tablet_pad_event(ev);
+	struct libinput_tablet_pad_mode_group *group;
+	unsigned int mode;
+
+	print_event_time(libinput_event_tablet_pad_get_time(p));
+
+	group = libinput_event_tablet_pad_get_mode_group(p);
+	mode = libinput_event_tablet_pad_get_mode(p);
+	printf("group %d mode %d\n",
+	       libinput_tablet_pad_mode_group_get_index(group),
+	       mode);
 }
 
 static int
@@ -748,6 +786,9 @@ handle_and_print_events(struct libinput *li)
 		case LIBINPUT_EVENT_TABLET_PAD_STRIP:
 			print_tablet_pad_strip_event(ev);
 			break;
+		case LIBINPUT_EVENT_TABLET_PAD_MODE:
+			print_tablet_pad_mode_event(ev);
+			break;
 		}
 
 		libinput_event_destroy(ev);
diff --git a/tools/event-gui.c b/tools/event-gui.c
index 605f00a3..5eeea1ed 100644
--- a/tools/event-gui.c
+++ b/tools/event-gui.c
@@ -843,6 +843,7 @@ handle_event_libinput(GIOChannel *source, GIOCondition condition, gpointer data)
 		case LIBINPUT_EVENT_TABLET_PAD_BUTTON:
 		case LIBINPUT_EVENT_TABLET_PAD_RING:
 		case LIBINPUT_EVENT_TABLET_PAD_STRIP:
+		case LIBINPUT_EVENT_TABLET_PAD_MODE:
 			break;
 		}