Digitizer HID interface : absolute coordinates for mouse cursor (#12851)

* Add digitizer HID interface for setting the mouse cursor position at
absolute screen coordinates. Tested on Pro Micro, Proton C and
Blackpill.

* Update docs/feature_digitizer.md

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update tmk_core/protocol/usb_descriptor.c

Co-authored-by: Ryan <fauxpark@gmail.com>

* Add missing copyrights
Add V-USB support

* Add support for digitizer dedicated endpoint for lufa and chibios.
Fix formatting issues
Move digitizer_task definition to the feature's base implementation file

* Run cformat on modified files

* Change digitizer report usage to Digitizer instead of Pen to avoid
pointer disappearing on Windows.

* Update tmk_core/protocol/vusb/vusb.c

Co-authored-by: Ryan <fauxpark@gmail.com>

* Run cformat from docker image

* Remove send_digitizer from host_driver_t and instead rely on the
declaration being the interface to the implementation in each
HW-specific usb implementation.

* Fix build : send_digitizer shouldn't be static in vusb and add
weak-linkage implementation for tests without usb implementation

* Change digitizer user interface to match pointing device's

* Update documentation with new API

Co-authored-by: a-chol <nothing@none.com>
Co-authored-by: Ryan <fauxpark@gmail.com>

2 files changed, 75 insertions, 0 deletions

diff --git a/quantum/digitizer.c b/quantum/digitizer.c
new file mode 100644
index 0000000000..e299867429
--- /dev/null
+++ b/quantum/digitizer.c
@@ -0,0 +1,34 @@
+/* Copyright 2021
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "digitizer.h"
+
+digitizer_t digitizerReport = {.tipswitch = 0, .inrange = 0, .id = 0, .x = 0, .y = 0, .status = DZ_INITIALIZED};
+
+__attribute__((weak)) void digitizer_send(void) {
+    if (digitizerReport.status & DZ_UPDATED) {
+        host_digitizer_send(&digitizerReport);
+        digitizerReport.status &= ~DZ_UPDATED;
+    }
+}
+
+__attribute__((weak)) void digitizer_task(void) { digitizer_send(); }
+
+digitizer_t digitizer_get_report(void) { return digitizerReport; }
+
+void digitizer_set_report(digitizer_t newDigitizerReport) {
+    digitizerReport = newDigitizerReport;
+    digitizerReport.status |= DZ_UPDATED;
+}
\ No newline at end of file
diff --git a/quantum/digitizer.h b/quantum/digitizer.h
new file mode 100644
index 0000000000..cef551567e
--- /dev/null
+++ b/quantum/digitizer.h
@@ -0,0 +1,41 @@
+/* Copyright 2021
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "quantum.h"
+
+#include <stdint.h>
+
+enum digitizer_status { DZ_INITIALIZED = 1, DZ_UPDATED = 2 };
+
+typedef struct {
+    int8_t  tipswitch;
+    int8_t  inrange;
+    uint8_t id;
+    float   x;
+    float   y;
+    uint8_t status : 2;
+} digitizer_t;
+
+extern digitizer_t digitizer;
+
+digitizer_t digitizer_get_report(void);
+
+void digitizer_set_report(digitizer_t newDigitizerReport);
+
+void digitizer_task(void);
+
+void host_digitizer_send(digitizer_t *digitizer);