keyboard hello world?

1 files changed, 108 insertions, 0 deletions

diff --git a/usb_keyboard.c b/usb_keyboard.c
new file mode 100644
index 0000000..5647403
--- /dev/null
+++ b/usb_keyboard.c
@@ -0,0 +1,108 @@
+#include "tusb.h"
+
+#include "tusb_helpers.h" /* for TUD_ENDPOINT_IN */
+#include "usb_common.h"
+#include "usb_keyboard.h"
+
+/**
+ * A USB-HID "Report Descriptor" (see USB-HID 1.11 §6.2.2 "Report
+ * Descriptor") describing a keyboard.
+ */
+static uint8_t const hid_report_descriptor_keyboard[] = { TUD_HID_REPORT_DESC_KEYBOARD() };
+
+static uint8_t kbd_ifc = 0;
+
+void usb_keyboard_init() {
+	if (kbd_ifc)
+		return;
+	usb_common_init();
+
+	kbd_ifc = usb_add_interface(cfgnum_std, TUD_HID_DESC_LEN, (uint8_t[]){
+		/* USB-HID input-only descriptor for inclusion in the config descriptor; consisting of 3 parts:
+		 *  1. an interface descriptor (USB 2.0 §9.6.5 "Interface"),
+		 *  2. a class-specific (class=HID) descriptor of type HID (USB-HID 1.11 §6.2.1 "HID Descriptor"),
+		 *  3. an endpoint descriptor for inputs (USB 2.0 §9.6.6 "Endpoint").
+		 * The TUD_HID_DESCRIPTOR() macro takes care of this for us.  */
+		TUD_HID_DESCRIPTOR(
+			0,                                      /* interface : bInterfaceNumber   ; Number of this interface (0-indexed) */
+			STRID_KBD_IFC,                          /* interface : iInterface         ; Index of string descriptor describing this interface */
+			HID_ITF_PROTOCOL_KEYBOARD,              /* interface : bInterfaceProtocol ; see USB-HID 1.11 §4.3 "Protocols" */
+			sizeof(hid_report_descriptor_keyboard), /* hid       : wDescriptorLength  ; Total size of report descriptor */
+			TUD_ENDPOINT_IN | 1,                    /* endpoint  : bEndpointAddress   ; Direction | endpoint number (arbitrary?) */
+			CFG_TUD_HID_EP_BUFSIZE,                 /* endpoint  : wMaxPacketSize     ; Maximum packet size this endpoint is capable of sending or receiving */
+			10),                                    /* endpoint  : bInterval          ; poll interval (in milliseconds?) */
+		});
+}
+
+#define kbd_buf_cap 1024
+static uint32_t kbd_buf[kbd_buf_cap];
+static size_t kbd_buf_beg = 0;
+static size_t kbd_buf_len = 0;
+
+static uint8_t ascii2keycode[128][2] = { HID_ASCII_TO_KEYCODE };
+
+void usb_keyboard_task(void) {
+	if (tud_hid_n_ready(kbd_ifc)) {
+		uint8_t const report_id = 0;
+		uint8_t modifier = 0;
+		uint8_t keycodes[6] = {0};
+
+		if (kbd_buf_len) {
+			if (ascii2keycode[kbd_buf[kbd_buf_beg]][0])
+				modifier = KEYBOARD_MODIFIER_LEFTSHIFT;
+			keycodes[0] = ascii2keycode[kbd_buf[kbd_buf_beg]][1];
+
+			kbd_buf_beg++;
+			if (kbd_buf_beg == kbd_buf_cap)
+				kbd_buf_beg = 0;
+			kbd_buf_len--;
+		}
+
+		tud_hid_n_keyboard_report(kbd_ifc, report_id, modifier, keycodes);
+	}
+}
+
+bool usb_keyboard_send_char(uint32_t ch) {
+	if (kbd_buf_len == kbd_buf_cap) /* buffer full */
+		return false;
+	if (ch > 0x7F) /* not ASCII */
+		return false;
+	kbd_buf[(kbd_buf_beg + kbd_buf_len++) % kbd_buf_cap] = ch;
+}
+
+bool usb_keyboard_is_flushed(void) {
+	return kbd_buf_len == 0;
+}
+
+/**
+ * Return a pointer to the HID "Report Descriptor" (see USB-HID 1.11
+ * §6.2.2 "Report Descriptor") for the given index.
+ */
+uint8_t const *tud_hid_descriptor_report_cb(uint8_t index) {
+       static uint8_t const *reports[] = {
+               hid_report_descriptor_keyboard,
+       };
+       if (index >= sizeof reports / sizeof reports[0])
+               return NULL;
+       return reports[index];
+}
+
+uint16_t tud_hid_get_report_cb(uint8_t instance, uint8_t report_id, hid_report_type_t report_type, uint8_t* buffer, uint16_t reqlen)
+{
+	// TODO not Implemented
+	(void) instance;
+	(void) report_id;
+	(void) report_type;
+	(void) buffer;
+	(void) reqlen;
+
+	return 0;
+}
+
+// Invoked when received SET_REPORT control request or
+// received data on OUT endpoint ( Report ID = 0, Type = 0 )
+void tud_hid_set_report_cb(uint8_t instance, uint8_t report_id, hid_report_type_t report_type, uint8_t const* buffer, uint16_t bufsize)
+{
+	// TODO not implemented
+	(void) report_id;
+}