Get *basic* USB report sending working.

CMakeLists.txt

@@ -2,6 +2,7 @@
 cmake_minimum_required(VERSION 3.13.1)
 
 list(APPEND BOARD_ROOT ${CMAKE_SOURCE_DIR})
+list(APPEND DTS_ROOT ${CMAKE_SOURCE_DIR})
 
 find_package(Zephyr)
 project(zmk)
@@ -10,5 +11,6 @@ project(zmk)
 # find_package(Zephyr) which defines the target.
 target_sources(app PRIVATE src/kscan.c)
 target_sources(app PRIVATE src/keymap.c)
+target_sources(app PRIVATE src/usb_hid.c)
 target_sources(app PRIVATE src/main.c)
 

boards/shields/petejohanson_handwire/petejohanson_handwire.overlay

@@ -1,3 +1,4 @@
+#include <dt-bindings/zmk/keys.h>
 
 / {
 	chosen {
@@ -9,17 +10,17 @@
 
 		default: layer_0 {
 			label = "Default";
-			keys = <10 2 3 8>;
+			keys = <KC_A KC_B KC_C KC_D>;
 		};
 
 		lower: layer_1 {
-			label = "Default";
+			label = "Lower";
-			keys = <9 2 3 5>;
+			keys = <KC_D KC_C KC_B KC_A>;
 		};
 
 		raise: layer_2 {
-			label = "Default";
+			label = "Raise";
-			keys = <8 1 2 3>;
+			keys = <KC_C KC_D KC_A KC_B>;
 		};
 	};
 
@@ -34,6 +35,7 @@
 		compatible = "gpio-kscan";
 		label = "Handwired GPIO KSCAN matrix";
 
+		diode-direction = "row2col";
 		row-gpios = <&arduino_header 8 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>,
 		            <&arduino_header 10 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
 		col-gpios = <&arduino_header 13 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>,

include/dt-bindings/zmk/keys.h

@@ -0,0 +1,5 @@
+
+#define KC_A 4
+#define KC_B 5
+#define KC_C 6
+#define KC_D 7

prj.conf

@@ -1,4 +1,6 @@
-# CONFIG_RUST=y
-# CONFIG_RUST_ALLOC_POOL=y
 CONFIG_KSCAN=y
 CONFIG_KSCAN_GPIO=y
+CONFIG_USB=y
+CONFIG_USB_DEVICE_STACK=y
+CONFIG_USB_DEVICE_HID=y
+CONFIG_USB_DEVICE_PRODUCT="ZMK Firmware"

src/kscan.c

@@ -12,6 +12,7 @@
 LOG_MODULE_REGISTER(zmk_kscan, CONFIG_ZMK_KSCAN_LOG_LEVEL);
 
 #include "keymap.h"
+#include "usb_hid.h"
 
 #define ZMK_KSCAN_EVENT_STATE_PRESSED 0
 #define ZMK_KSCAN_EVENT_STATE_RELEASED 1
@@ -35,7 +36,6 @@ static void zmk_kscan_callback(struct device *dev, u32_t row, u32_t column, bool
 		.column = column,
 		.state = (pressed ? ZMK_KSCAN_EVENT_STATE_PRESSED : ZMK_KSCAN_EVENT_STATE_RELEASED)
 	};
-	printk("Row: %d, col: %d, pressed: %s\n", ev.row, ev.column, (pressed ? "true" : "false"));
 
 	k_msgq_put(&zmk_kscan_msgq, &ev, K_NO_WAIT);
 	k_work_submit(&msg_processor.work);
@@ -44,13 +44,17 @@ static void zmk_kscan_callback(struct device *dev, u32_t row, u32_t column, bool
 void zmk_kscan_process_msgq(struct k_work *item)
 {
 	struct zmk_kscan_event ev;
-	printk("process messages!\n");
 
 	while(k_msgq_get(&zmk_kscan_msgq, &ev, K_NO_WAIT) == 0) {
 		bool pressed = (ev.state == ZMK_KSCAN_EVENT_STATE_PRESSED);
 		// TODO: More than basic mapping, layers, etc.
 		enum hid_kbd_code code = zmk_keymap_keycode_from_position(ev.row, ev.column);
-		printk("Row: %d, col: %d, code: %d, pressed: %s\n", ev.row, ev.column, code, (pressed ? "true" : "false"));
+		LOG_DBG("Row: %d, col: %d, code: %d, pressed: %s\n", ev.row, ev.column, code, (pressed ? "true" : "false"));
+		if (pressed) {
+			zmk_usb_hid_press_key(code);
+		} else {
+			zmk_usb_hid_release_key(code);
+		}
 	}
 }
 
@@ -62,7 +66,6 @@ int zmk_kscan_init(char* name)
 		return -EINVAL;
 	}
 
-
 	k_work_init(&msg_processor.work, zmk_kscan_process_msgq);
 
 	kscan_config(dev, zmk_kscan_callback);

src/main.c

@@ -9,6 +9,7 @@
 #include <devicetree.h>
 
 #include "kscan.h"
+#include "usb_hid.h"
 
 void main(void)
 {
@@ -18,4 +19,9 @@ void main(void)
 		printk("Keyboard Scan Init Failed\n");
 		return;
 	}
+
+	if (zmk_usb_hid_init() < 0) {
+		printk("USB HID Init Failed\n");
+		return;
+	}
 }

src/usb_hid.c

@@ -0,0 +1,81 @@
+
+#include <device.h>
+
+#include <usb/usb_device.h>
+#include <usb/class/usb_hid.h>
+
+LOG_MODULE_REGISTER(zmk_usb_hid, CONFIG_ZMK_USB_HID_LOG_LEVEL);
+
+static const u8_t hid_report_desc[] = HID_KEYBOARD_REPORT_DESC();
+static enum usb_dc_status_code usb_status;
+
+static struct device *hid_dev;
+static u8_t report[8] = { 0x00, 0x00 };
+
+#define KEY_OFFSET 0x02
+#define MAX_KEYS 6
+
+int zmk_usb_hid_press_key(enum hid_kbd_code code)
+{
+	if (usb_status == USB_DC_SUSPEND) {
+		return usb_wakeup_request();
+	}
+
+	for (int idx = 0; idx < MAX_KEYS; idx++) {
+		if (report[idx + KEY_OFFSET] != 0U) {
+			continue;
+		}
+
+		report[idx + KEY_OFFSET] = code;
+
+		return hid_int_ep_write(hid_dev, report, sizeof(report), NULL);
+	}
+
+	return -EINVAL;
+}
+
+int zmk_usb_hid_release_key(enum hid_kbd_code code)
+{
+	for (int idx = 0; idx < MAX_KEYS; idx++) {
+		if (report[idx + KEY_OFFSET] != code) {
+			continue;
+		}
+
+		report[idx + KEY_OFFSET] = 0U;
+
+		return hid_int_ep_write(hid_dev, report, sizeof(report), NULL);
+	}
+
+	return -EINVAL;
+}
+
+void usb_hid_status_cb(enum usb_dc_status_code status, const u8_t *params)
+{
+	usb_status = status;
+};
+
+int zmk_usb_hid_init()
+{
+	int usb_enable_ret;
+
+	hid_dev = device_get_binding("HID_0");
+	if (hid_dev == NULL) {
+		LOG_ERR("Unable to locate HID device");
+		return -EINVAL;
+	}
+
+	usb_hid_register_device(hid_dev,
+	                        hid_report_desc, sizeof(hid_report_desc),
+	                        NULL);
+
+	usb_hid_init(hid_dev);
+
+	usb_enable_ret = usb_enable(usb_hid_status_cb);
+
+	if (usb_enable_ret != 0) {
+		LOG_ERR("Unable to enable USB");
+		return -EINVAL;
+	}
+
+	return 0;
+}

src/usb_hid.h

@@ -0,0 +1,14 @@
+#ifndef ZMK_USB_HID
+#define ZMK_USB_HID
+
+#include <usb/usb_device.h>
+#include <usb/class/usb_hid.h>
+
+int zmk_usb_hid_init();
+
+// TODO: Modifiers!
+
+int zmk_usb_hid_press_key(enum hid_kbd_code code);
+int zmk_usb_hid_release_key(enum hid_kbd_code code);
+
+#endif