Skip processing unused controllers via mask

include/PR/os_cont.h

@@ -212,6 +212,13 @@ typedef struct {
 #define CONT_ERR_VOICE_WORD        14
 #define CONT_ERR_VOICE_NO_RESPONSE 15
 
+// Controller mask values
+#define CONT_P1 (1 << 0)
+#define CONT_P2 (1 << 1)
+#define CONT_P3 (1 << 2)
+#define CONT_P4 (1 << 3)
+
+// Controller types
 #define CONT_TYPE_N64 0
 #define CONT_TYPE_GCN 1
 
@@ -228,6 +235,7 @@ typedef struct {
  * Extern variables
  *
  */
+extern u8 __osControllerMask;
 
 /**************************************************************************
  *
@@ -244,6 +252,7 @@ extern s32 osContStartReadData(OSMesgQueue*);
 #ifndef _HW_VERSION_1
 extern s32 osContSetCh(u8);
 #endif
+extern s32 osContSetMask(u8 ch);
 extern void osContGetQuery(OSContStatus*);
 extern void osContGetReadData(OSContPad*);
 

src/io/contreaddata.c

@@ -62,6 +62,12 @@ void osContGetReadData(OSContPad* data) {
     int i;
 
     for (i = 0; i < __osMaxControllers; i++, data++) {
+        // Skip current channel if controller not connected
+        if ((__osControllerMask & (1 << i)) == 0) {
+            ptr += sizeof(__OSContReadFormat);
+            continue;
+        }
+
         if (__osControllerTypes[i] == CONT_TYPE_GCN) {
             s32 stick_x, stick_y, c_stick_x, c_stick_y;
             readformatgcn = *(__OSContGCNShortPollFormat*)ptr;
@@ -113,9 +119,6 @@ static void __osPackReadData(void) {
 
     __osContPifRam.pifstatus = CONT_CMD_EXE;
     readformat.dummy = CONT_CMD_NOP;
-    readformat.txsize = CONT_CMD_READ_BUTTON_TX;
-    readformat.rxsize = CONT_CMD_READ_BUTTON_RX;
-    readformat.cmd = CONT_CMD_READ_BUTTON;
     readformat.button = 0xFFFF;
     readformat.stick_x = -1;
     readformat.stick_y = -1;
@@ -135,7 +138,18 @@ static void __osPackReadData(void) {
     readformatgcn.stick_y = -1;
 
     for (i = 0; i < __osMaxControllers; i++) {
-        if (__osControllerTypes[i] == CONT_TYPE_GCN) {
+        if ((__osControllerMask & (1 << i)) == 0) {
+            // In the Joybus frame, a packet is sent to the PIF chip describing the number of bytes to transfer and
+            // receive over the protocol. There are two special commands, 0x00 (skip) and 0xFF (nop). This function
+            // sends a packet with the layout: FF FF FF 00 FF FF FF FF, basically saying to skip the channel, with some
+            // extra bytes that do nothing, allowing the next packet to be processed. This wastes memory, but it works.
+            // Source: https://n64brew.dev/wiki/PIF-NUS#Joybus_frame_(controller_and_EEPROM_communication)
+            readformat.txsize = CONT_CMD_NOP;
+            readformat.rxsize = CONT_CMD_NOP;
+            readformat.cmd = 0;
+            *(__OSContReadFormat*)ptr = readformat;
+            ptr += sizeof(__OSContReadFormat);
+        } else if (__osControllerTypes[i] == CONT_TYPE_GCN) {
             readformatgcn.rumble = __osGamecubeRumbleEnabled[i];
             *(__OSContGCNShortPollFormat*)ptr = readformatgcn;
             ptr += sizeof(__OSContGCNShortPollFormat);

src/io/controller.c

@@ -12,6 +12,7 @@ u8 __osGamecubeRumbleEnabled[MAXCONTROLLERS];
 OSTimer __osEepromTimer;
 OSMesgQueue __osEepromTimerQ ALIGNED(0x8);
 OSMesg __osEepromTimerMsg;
+u8 __osControllerMask;
 
 s32 __osContinitialized = FALSE;
 
@@ -27,6 +28,7 @@ s32 osContInit(OSMesgQueue* mq, u8* bitpattern, OSContStatus* data) {
     }
 
     __osContinitialized = TRUE;
+    __osControllerMask = CONT_P1 | CONT_P2 | CONT_P3 | CONT_P4;
 
     t = osGetTime();
     if (t < OS_USEC_TO_CYCLES(500000)) {
@@ -35,7 +37,7 @@ s32 osContInit(OSMesgQueue* mq, u8* bitpattern, OSContStatus* data) {
         osRecvMesg(&timerMesgQueue, &dummy, OS_MESG_BLOCK);
     }
 
-    __osMaxControllers = 4;
+    __osMaxControllers = MAXCONTROLLERS;
 
     __osPackRequestData(CONT_CMD_REQUEST_STATUS);
 

src/io/contsetch.c

@@ -7,17 +7,39 @@
  * to multiple direct SI devices.
  */
 s32 osContSetCh(u8 ch) {
+    return osContSetMask((1 << ch) - 1);
+}
+
+/*
+ * Use a mask to detect controller channels instead, allowing the PIF to skip channels instead of
+ * spending time reading data.
+ * This does not work on iQue Player.
+ */
+s32 osContSetMask(u8 ch) {
     s32 ret = 0;
 
+#ifdef BBPLAYER
+    __osControllerMask = (CONT_P1 | CONT_P2 | CONT_P3 | CONT_P4);
+    __osMaxControllers = MAXCONTROLLERS;
+    return ret;
+#else
     __osSiGetAccess();
 
-    if (ch > MAXCONTROLLERS) {
+    if ((ch == 0) || (ch > (CONT_P1 | CONT_P2 | CONT_P3 | CONT_P4))) {
+        __osControllerMask = (CONT_P1 | CONT_P2 | CONT_P3 | CONT_P4);
         __osMaxControllers = MAXCONTROLLERS;
     } else {
-        __osMaxControllers = ch;
+        __osControllerMask = ch;
+        for (s32 i = 0; i < MAXCONTROLLERS; i++) {
+            if (ch & (1 << i)) {
+                __osMaxControllers = i;
+            }
+        }
+        __osMaxControllers++;
     }
 
     __osContLastCmd = CONT_CMD_END;
     __osSiRelAccess();
     return ret;
+#endif
 }

src/io/pfsisplug.c

@@ -28,6 +28,9 @@ s32 osPfsIsPlug(OSMesgQueue* mq, u8* pattern) {
         __osPfsGetInitData(&bitpattern, &contData[0]);
 
         for (channel = 0; channel < __osMaxControllers; channel++) {
+            if ((__osControllerMask & (1 << channel)) == 0) {
+                continue;
+            }
             if ((contData[channel].status & CONT_ADDR_CRC_ER) == 0) {
                 crcErrorCount--;
                 break;
@@ -40,6 +43,9 @@ s32 osPfsIsPlug(OSMesgQueue* mq, u8* pattern) {
     } while (crcErrorCount > 0);
 
     for (channel = 0; channel < __osMaxControllers; channel++) {
+        if ((__osControllerMask & (1 << channel)) == 0) {
+            continue;
+        }
         if ((contData[channel].errno == 0) && ((contData[channel].status & CONT_CARD_ON) != 0)) {
             bits |= (1 << channel);
         }
@@ -57,15 +63,22 @@ void __osPfsRequestData(u8 cmd) {
     __osContLastCmd = cmd;
     __osPfsPifRam.pifstatus = CONT_CMD_EXE;
     requestformat.dummy = CONT_CMD_NOP;
-    requestformat.txsize = CONT_CMD_REQUEST_STATUS_TX;
-    requestformat.rxsize = CONT_CMD_REQUEST_STATUS_RX;
-    requestformat.cmd = cmd;
     requestformat.typeh = CONT_CMD_NOP;
     requestformat.typel = CONT_CMD_NOP;
     requestformat.status = CONT_CMD_NOP;
     requestformat.dummy1 = CONT_CMD_NOP;
 
     for (i = 0; i < __osMaxControllers; i++) {
+        if ((__osControllerMask & (1 << i)) == 0) {
+            // See __osPackReadData in contreaddata.c for an explanation for this behavior.
+            requestformat.txsize = CONT_CMD_NOP;
+            requestformat.rxsize = CONT_CMD_NOP;
+            requestformat.cmd = 0;
+        } else {
+            requestformat.txsize = CONT_CMD_REQUEST_STATUS_TX;
+            requestformat.rxsize = CONT_CMD_REQUEST_STATUS_RX;
+            requestformat.cmd = cmd;
+        }
         *((__OSContRequesFormat*)ptr) = requestformat;
         ptr += sizeof(__OSContRequesFormat);
     }
@@ -82,6 +95,9 @@ void __osPfsGetInitData(u8* pattern, OSContStatus* data) {
     ptr = (u8*)&__osPfsPifRam;
 
     for (i = 0; i < __osMaxControllers; i++, ptr += sizeof(requestformat), data++) {
+        if ((__osControllerMask & (1 << i)) == 0) {
+            continue;
+        }
         requestformat = *((__OSContRequesFormat*)ptr);
         data->errno = CHNL_ERR(requestformat);