Use a single endpoint for HID reports

docs/config_options.md

@@ -260,3 +260,32 @@ Use these to enable or disable building certain features. The more you have enab
   * Forces the keyboard to wait for a USB connection to be established before it starts up
 * `NO_USB_STARTUP_CHECK`
   * Disables usb suspend check after keyboard startup. Usually the keyboard waits for the host to wake it up before any tasks are performed. This is useful for split keyboards as one half will not get a wakeup call but must send commands to the master.
+
+## USB Endpoint Limitations
+
+In order to provide services over USB, QMK has to use USB endpoints.
+These are a finite resource: each microcontroller has only a certain number.
+This limits what features can be enabled together.
+If the available endpoints are exceeded, a build error is thrown.
+
+The following features can require separate endpoints:
+
+* `MOUSEKEY_ENABLE`
+* `EXTRAKEY_ENABLE`
+* `CONSOLE_ENABLE`
+* `NKRO_ENABLE`
+* `MIDI_ENABLE`
+* `RAW_ENABLE`
+* `VIRTSER_ENABLE`
+
+In order to improve utilisation of the endpoints, the HID features can be combined to use a single endpoint.
+By default, `MOUSEKEY`, `EXTRAKEY`, and `NKRO` are combined into a single endpoint.
+
+The base keyboard functionality can also be combined into the endpoint,
+by setting `KEYBOARD_SHARED_EP = yes`.
+This frees up one more endpoint,
+but it can prevent the keyboard working in some BIOSes,
+as they do not implement Boot Keyboard protocol switching.
+
+Combining the mouse also breaks Boot Mouse compatibility.
+The mouse can be uncombined by setting `MOUSE_SHARED_EP = no` if this functionality is required.

tmk_core/common.mk

@@ -80,15 +80,31 @@ else
     TMK_COMMON_SRC += $(COMMON_DIR)/magic.c
 endif
 
+SHARED_EP_ENABLE = no
+MOUSE_SHARED_EP ?= yes
+ifeq ($(strip $(KEYBOARD_SHARED_EP)), yes)
+    TMK_COMMON_DEFS += -DKEYBOARD_SHARED_EP
+    SHARED_EP_ENABLE = yes
+    # With the current usb_descriptor.c code,
+    # you can't share kbd without sharing mouse;
+    # that would be a very unexpected use case anyway
+    MOUSE_SHARED_EP = yes
+endif
 
 ifeq ($(strip $(MOUSEKEY_ENABLE)), yes)
     TMK_COMMON_SRC += $(COMMON_DIR)/mousekey.c
     TMK_COMMON_DEFS += -DMOUSEKEY_ENABLE
     TMK_COMMON_DEFS += -DMOUSE_ENABLE
+
+    ifeq ($(strip $(MOUSE_SHARED_EP)), yes)
+        TMK_COMMON_DEFS += -DMOUSE_SHARED_EP
+        SHARED_EP_ENABLE = yes
+    endif
 endif
 
 ifeq ($(strip $(EXTRAKEY_ENABLE)), yes)
     TMK_COMMON_DEFS += -DEXTRAKEY_ENABLE
+    SHARED_EP_ENABLE = yes
 endif
 
 ifeq ($(strip $(RAW_ENABLE)), yes)
@@ -109,6 +125,7 @@ endif
 
 ifeq ($(strip $(NKRO_ENABLE)), yes)
     TMK_COMMON_DEFS += -DNKRO_ENABLE
+    SHARED_EP_ENABLE = yes
 endif
 
 ifeq ($(strip $(USB_6KRO_ENABLE)), yes)
@@ -180,6 +197,10 @@ ifeq ($(strip $(KEYMAP_SECTION_ENABLE)), yes)
     endif
 endif
 
+ifeq ($(strip $(SHARED_EP_ENABLE)), yes)
+    TMK_COMMON_DEFS += -DSHARED_EP_ENABLE
+endif
+
 # Bootloader address
 ifdef STM32_BOOTLOADER_ADDRESS
     TMK_COMMON_DEFS += -DSTM32_BOOTLOADER_ADDRESS=$(STM32_BOOTLOADER_ADDRESS)

tmk_core/common/host.c

@@ -22,6 +22,11 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "util.h"
 #include "debug.h"
 
+#ifdef NKRO_ENABLE
+  #include "keycode_config.h"
+  extern keymap_config_t keymap_config;
+#endif
+
 static host_driver_t *driver;
 static uint16_t last_system_report = 0;
 static uint16_t last_consumer_report = 0;
@@ -46,6 +51,20 @@ uint8_t host_keyboard_leds(void)
 void host_keyboard_send(report_keyboard_t *report)
 {
     if (!driver) return;
+#if defined(NKRO_ENABLE) && defined(NKRO_SHARED_EP)
+    if (keyboard_protocol && keymap_config.nkro) {
+        /* The callers of this function assume that report->mods is where mods go in.
+         * But report->nkro.mods can be at a different offset if core keyboard does not have a report ID.
+         */
+        report->nkro.mods = report->mods;
+        report->nkro.report_id = REPORT_ID_NKRO;
+    } else
+#endif
+    {
+#ifdef KEYBOARD_SHARED_EP
+        report->report_id = REPORT_ID_KEYBOARD;
+#endif
+    }
     (*driver->send_keyboard)(report);
 
     if (debug_keyboard) {
@@ -60,6 +79,9 @@ void host_keyboard_send(report_keyboard_t *report)
 void host_mouse_send(report_mouse_t *report)
 {
     if (!driver) return;
+#ifdef MOUSE_SHARED_EP
+    report->report_id = REPORT_ID_MOUSE;
+#endif
     (*driver->send_mouse)(report);
 }
 

tmk_core/common/report.c

@@ -19,6 +19,7 @@
 #include "keycode_config.h"
 #include "debug.h"
 #include "util.h"
+#include <string.h>
 
 /** \brief has_anykey
  *
@@ -27,8 +28,16 @@
 uint8_t has_anykey(report_keyboard_t* keyboard_report)
 {
     uint8_t cnt = 0;
-    for (uint8_t i = 1; i < KEYBOARD_REPORT_SIZE; i++) {
-        if (keyboard_report->raw[i])
+    uint8_t *p = keyboard_report->keys;
+    uint8_t lp = sizeof(keyboard_report->keys);
+#ifdef NKRO_ENABLE
+    if (keyboard_protocol && keymap_config.nkro) {
+        p = keyboard_report->nkro.bits;
+        lp = sizeof(keyboard_report->nkro.bits);
+    }
+#endif
+    while (lp--) {
+        if (*p++)
             cnt++;
     }
     return cnt;
@@ -237,7 +246,11 @@ void del_key_from_report(report_keyboard_t* keyboard_report, uint8_t key)
 void clear_keys_from_report(report_keyboard_t* keyboard_report)
 {
     // not clear mods
-    for (int8_t i = 1; i < KEYBOARD_REPORT_SIZE; i++) {
-        keyboard_report->raw[i] = 0;
+#ifdef NKRO_ENABLE
+    if (keyboard_protocol && keymap_config.nkro) {
+        memset(keyboard_report->nkro.bits, 0, sizeof(keyboard_report->nkro.bits));
+        return;
     }
+#endif
+    memset(keyboard_report->keys, 0, sizeof(keyboard_report->keys));
 }

tmk_core/common/report.h

@@ -23,9 +23,11 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 
 /* report id */
-#define REPORT_ID_MOUSE     1
-#define REPORT_ID_SYSTEM    2
-#define REPORT_ID_CONSUMER  3
+#define REPORT_ID_KEYBOARD  1
+#define REPORT_ID_MOUSE     2
+#define REPORT_ID_SYSTEM    3
+#define REPORT_ID_CONSUMER  4
+#define REPORT_ID_NKRO      5
 
 /* mouse buttons */
 #define MOUSE_BTN1 (1<<0)
@@ -72,32 +74,35 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define SYSTEM_WAKE_UP          0x0083
 
 
+#define NKRO_SHARED_EP
 /* key report size(NKRO or boot mode) */
 #if defined(NKRO_ENABLE)
-  #if defined(PROTOCOL_PJRC)
-    #include "usb.h"
-    #define KEYBOARD_REPORT_SIZE KBD2_SIZE
-    #define KEYBOARD_REPORT_KEYS (KBD2_SIZE - 2)
-    #define KEYBOARD_REPORT_BITS (KBD2_SIZE - 1)
-  #elif defined(PROTOCOL_LUFA) || defined(PROTOCOL_CHIBIOS)
+  #if defined(PROTOCOL_LUFA) || defined(PROTOCOL_CHIBIOS)
     #include "protocol/usb_descriptor.h"
-    #define KEYBOARD_REPORT_SIZE NKRO_EPSIZE
-    #define KEYBOARD_REPORT_KEYS (NKRO_EPSIZE - 2)
-    #define KEYBOARD_REPORT_BITS (NKRO_EPSIZE - 1)
+    #define KEYBOARD_REPORT_BITS (SHARED_EPSIZE - 2)
   #elif defined(PROTOCOL_ARM_ATSAM)
     #include "protocol/arm_atsam/usb/udi_device_epsize.h"
-    #define KEYBOARD_REPORT_SIZE NKRO_EPSIZE
-    #define KEYBOARD_REPORT_KEYS (NKRO_EPSIZE - 2)
     #define KEYBOARD_REPORT_BITS (NKRO_EPSIZE - 1)
+    #undef NKRO_SHARED_EP
+    #undef MOUSE_SHARED_EP
   #else
     #error "NKRO not supported with this protocol"
+  #endif
 #endif
 
+#ifdef KEYBOARD_SHARED_EP
+#   define KEYBOARD_REPORT_SIZE 9
 #else
 #   define KEYBOARD_REPORT_SIZE 8
-#   define KEYBOARD_REPORT_KEYS 6
 #endif
 
+#define KEYBOARD_REPORT_KEYS 6
+
+/* VUSB hardcodes keyboard and mouse+extrakey only */
+#if defined(PROTOCOL_VUSB)
+  #undef KEYBOARD_SHARED_EP
+  #undef MOUSE_SHARED_EP
+#endif
 
 #ifdef __cplusplus
 extern "C" {
@@ -126,19 +131,28 @@ extern "C" {
 typedef union {
     uint8_t raw[KEYBOARD_REPORT_SIZE];
     struct {
+#ifdef KEYBOARD_SHARED_EP
+        uint8_t report_id;
+#endif
         uint8_t mods;
         uint8_t reserved;
         uint8_t keys[KEYBOARD_REPORT_KEYS];
     };
 #ifdef NKRO_ENABLE
-    struct {
+    struct nkro_report {
+#ifdef NKRO_SHARED_EP
+        uint8_t report_id;
+#endif
         uint8_t mods;
         uint8_t bits[KEYBOARD_REPORT_BITS];
     } nkro;
 #endif
 } __attribute__ ((packed)) report_keyboard_t;
 
 typedef struct {
+#ifdef MOUSE_SHARED_EP
+    uint8_t report_id;
+#endif
     uint8_t buttons;
     int8_t x;
     int8_t y;

tmk_core/protocol/arm_atsam/usb/udi_hid_kbd.c

@@ -54,6 +54,7 @@
 #include "udi_hid.h"
 #include "udi_hid_kbd.h"
 #include <string.h>
+#include "report.h"
 
 //***************************************************************************
 // KBD
@@ -430,7 +431,7 @@ UDC_DESC_STORAGE udi_hid_exk_report_desc_t udi_hid_exk_report_desc = {
         0x05, 0x01,         // Usage Page (Generic Desktop),
         0x09, 0x80,         // Usage (System Control),
         0xA1, 0x01,         // Collection (Application),
-        0x85, 0x02,         //   Report ID (2) (System),
+        0x85, REPORT_ID_SYSTEM,         //   Report ID (2) (System),
         0x16, 0x01, 0x00,   //   Logical Minimum (1),
         0x26, 0x03, 0x00,   //   Logical Maximum (3),
         0x1A, 0x81, 0x00,   //   Usage Minimum (81) (System Power Down),
@@ -445,7 +446,7 @@ UDC_DESC_STORAGE udi_hid_exk_report_desc_t udi_hid_exk_report_desc = {
         0x05, 0x0C,         // Usage Page (Consumer),
         0x09, 0x01,         // Usage (Consumer Control),
         0xA1, 0x01,         // Collection (Application),
-        0x85, 0x03,         //   Report ID (3) (Consumer),
+        0x85, REPORT_ID_CONSUMER,         //   Report ID (3) (Consumer),
         0x16, 0x01, 0x00,   //   Logical Minimum (1),
         0x26, 0x9C, 0x02,   //   Logical Maximum (668),
         0x1A, 0x01, 0x00,   //   Usage Minimum (1),