patch-2.4.19 linux-2.4.19/drivers/macintosh/via-maciisi.c

• Lines: 608
• Date: Fri Aug 2 17:39:44 2002
• Orig file: linux-2.4.18/drivers/macintosh/via-maciisi.c
• Orig date: Sun Feb 13 11:21:42 2000

diff -urN linux-2.4.18/drivers/macintosh/via-maciisi.c linux-2.4.19/drivers/macintosh/via-maciisi.c
@@ -9,7 +9,11 @@
  *
  * Original sources (c) Alan Cox, Paul Mackerras, and others.
  *
- * Rewritten for Unified ADB by David Huggins-Daines <dhd@debian.org> */
+ * Rewritten for Unified ADB by David Huggins-Daines <dhd@debian.org>
+ * 
+ * 7/13/2000- extensive changes by Andrew McPherson <andrew@macduff.dhs.org>
+ * Works about 30% of the time now.
+ */
 
 #include <linux/types.h>
 #include <linux/errno.h>
@@ -56,6 +60,8 @@
 
 #define ADB_DELAY 150
 
+#undef DEBUG_MACIISI_ADB
+
 static struct adb_request* current_req = NULL;
 static struct adb_request* last_req = NULL;
 static unsigned char maciisi_rbuf[16];
@@ -63,6 +69,8 @@
 static int data_index;
 static int reading_reply;
 static int reply_len;
+static int tmp;
+static int need_sync;
 
 static enum maciisi_state {
     idle,
@@ -73,12 +81,13 @@
 static int maciisi_probe(void);
 static int maciisi_init(void);
 static int maciisi_send_request(struct adb_request* req, int sync);
+static void maciisi_sync(struct adb_request *req);
 static int maciisi_write(struct adb_request* req);
 static void maciisi_interrupt(int irq, void* arg, struct pt_regs* regs);
 static void maciisi_input(unsigned char *buf, int nb, struct pt_regs *regs);
 static int maciisi_init_via(void);
 static void maciisi_poll(void);
-static void maciisi_start(void);
+static int maciisi_start(void);
 
 struct adb_driver via_maciisi_driver = {
 	"Mac IIsi",
@@ -114,63 +123,105 @@
 		return err;
 	}
 
-	if (request_irq(IRQ_MAC_ADB, maciisi_interrupt, IRQ_FLG_LOCK, 
+	if (request_irq(IRQ_MAC_ADB, maciisi_interrupt, IRQ_FLG_LOCK | IRQ_FLG_FAST, 
 			"ADB", maciisi_interrupt)) {
 		printk(KERN_ERR "maciisi_init: can't get irq %d\n", IRQ_MAC_ADB);
 		return -EAGAIN;
 	}
 
-	printk("adb: Mac IIsi driver v0.1 for Unified ADB.\n");
+	printk("adb: Mac IIsi driver v0.2 for Unified ADB.\n");
 	return 0;
 }
 
+/* Flush data from the ADB controller */
 static void
 maciisi_stfu(void)
 {
 	int status = via[B] & (TIP|TREQ);
 
 	if (status & TREQ) {
+#ifdef DEBUG_MACIISI_ADB
 		printk (KERN_DEBUG "maciisi_stfu called with TREQ high!\n");
+#endif
 		return;
 	}
+	
+	udelay(ADB_DELAY);
+	via[ACR] &= ~SR_OUT;
+	via[IER] = IER_CLR | SR_INT;
 
-	/* start transfer */
-	via[B] |= TIP;
-	while (!(status & TREQ)) {
-		int poll_timeout = ADB_DELAY * 5;
-		/* Poll for SR interrupt */
-		while (!(via[IFR] & SR_INT) && poll_timeout-- > 0)
-			status = via[B] & (TIP|TREQ);
-		via[SR]; /* Clear shift register */
-		printk(KERN_DEBUG "maciisi_stfu: status %x timeout %d\n",
-		       status, poll_timeout);
-		
-		/* ACK on-off */
-		via[B] |= TACK;
+	udelay(ADB_DELAY);
+
+	status = via[B] & (TIP|TREQ);
+
+	if (!(status & TREQ))
+	{
+		via[B] |= TIP;
+
+		while(1)
+		{
+			int poll_timeout = ADB_DELAY * 5;
+			/* Poll for SR interrupt */
+			while (!(via[IFR] & SR_INT) && poll_timeout-- > 0)
+				status = via[B] & (TIP|TREQ);
+
+			tmp = via[SR]; /* Clear shift register */
+#ifdef DEBUG_MACIISI_ADB
+			printk(KERN_DEBUG "maciisi_stfu: status %x timeout %d data %x\n",
+			       status, poll_timeout, tmp);
+#endif	
+			if(via[B] & TREQ)
+				break;
+	
+			/* ACK on-off */
+			via[B] |= TACK;
+			udelay(ADB_DELAY);
+			via[B] &= ~TACK;
+		}
+
+		/* end frame */
+		via[B] &= ~TIP;
 		udelay(ADB_DELAY);
-		via[B] &= ~TACK;
 	}
-	/* end frame */
-	via[B] &= ~TIP;
+
+	via[IER] = IER_SET | SR_INT;	
 }
 
 /* All specifically VIA-related initialization goes here */
 static int
 maciisi_init_via(void)
 {
+	int	i;
+	
 	/* Set the lines up. We want TREQ as input TACK|TIP as output */
 	via[DIRB] = (via[DIRB] | TACK | TIP) & ~TREQ;
 	/* Shift register on input */
 	via[ACR]  = (via[ACR] & ~SR_CTRL) | SR_EXT;
+#ifdef DEBUG_MACIISI_ADB
 	printk(KERN_DEBUG "maciisi_init_via: initial status %x\n", via[B] & (TIP|TREQ));
+#endif
+	/* Wipe any pending data and int */
+	tmp = via[SR];
+	/* Enable keyboard interrupts */
+	via[IER] = IER_SET | SR_INT;
 	/* Set initial state: idle */
 	via[B] &= ~(TACK|TIP);
-	/* Wipe any pending data and int */
-	via[SR];
-	if (!(via[B] & TREQ))
+	/* Clear interrupt bit */
+	via[IFR] = SR_INT;
+
+	for(i = 0; i < 60; i++) {
+		udelay(ADB_DELAY);
 		maciisi_stfu();
-	via[IER] = IER_SET | SR_INT;
+		udelay(ADB_DELAY);
+		if(via[B] & TREQ)
+			break;
+	}
+	if (i == 60)
+		printk(KERN_ERR "maciisi_init_via: bus jam?\n");
+
 	maciisi_state = idle;
+	need_sync = 0;
+
 	return 0;
 }
 
@@ -179,41 +230,77 @@
 maciisi_send_request(struct adb_request* req, int sync)
 {
 	int i;
-	static int dump_packet = 1;
+	int count;
+
+#ifdef DEBUG_MACIISI_ADB
+	static int dump_packet = 0;
+#endif
 
 	if (via == NULL) {
 		req->complete = 1;
 		return -ENXIO;
 	}
 
+#ifdef DEBUG_MACIISI_ADB
 	if (dump_packet) {
 		printk(KERN_DEBUG "maciisi_send_request:");
 		for (i = 0; i < req->nbytes; i++) {
 			printk(" %.2x", req->data[i]);
 		}
-		printk("\n");
+		printk(" sync %d\n", sync);
 	}
+#endif
+
 	req->reply_expected = 1;
 	
 	i = maciisi_write(req);
 	if (i)
+	{
+		/* Normally, if a packet requires syncing, that happens at the end of
+		 * maciisi_send_request. But if the transfer fails, it will be restarted
+		 * by maciisi_interrupt(). We use need_sync to tell maciisi_interrupt
+		 * when to sync a packet that it sends out.
+		 * 
+		 * Suggestions on a better way to do this are welcome.
+		 */
+		if(i == -EBUSY && sync)
+			need_sync = 1;
+		else
+			need_sync = 0;
 		return i;
-	
-	if (sync) {
-		while (!req->complete) {
-			maciisi_poll();
-		}
 	}
+	if(sync)
+		maciisi_sync(req);
+	
 	return 0;
 }
 
+/* Poll the ADB chip until the request completes */
+static void maciisi_sync(struct adb_request *req)
+{
+	int count = 0; 
+
+#ifdef DEBUG_MACIISI_ADB
+	printk(KERN_DEBUG "maciisi_sync called\n");
+#endif
+
+	/* If for some reason the ADB chip shuts up on us, we want to avoid an endless loop. */
+	while (!req->complete && count++ < 50) {
+		maciisi_poll();
+	}
+	/* This could be BAD... when the ADB controller doesn't respond
+	 * for this long, it's probably not coming back :-( */
+	if(count >= 50) /* Hopefully shouldn't happen */
+		printk(KERN_ERR "maciisi_send_request: poll timed out!\n");
+}
+
 /* Enqueue a request, and run the queue if possible */
 static int
 maciisi_write(struct adb_request* req)
 {
 	unsigned long flags;
+	int i;
 
-  	printk(KERN_DEBUG "maciisi_write called, state=%d ifr=%x\n", maciisi_state, via[IFR]);
 	/* We will accept CUDA packets - the VIA sends them to us, so
            it figures that we should be able to send them to it */
 	if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) {
@@ -225,7 +312,9 @@
 	req->sent = 0;
 	req->complete = 0;
 	req->reply_len = 0;
-	save_flags(flags); cli();
+	
+	save_flags(flags);
+	cli();
 
 	if (current_req) {
 		last_req->next = req;
@@ -235,44 +324,68 @@
 		last_req = req;
 	}
 	if (maciisi_state == idle)
-		maciisi_start();
+	{
+		i = maciisi_start();
+		if(i != 0)
+		{
+			restore_flags(flags);
+			return i;
+		}
+	}
 	else
+	{
+#ifdef DEBUG_MACIISI_ADB
 		printk(KERN_DEBUG "maciisi_write: would start, but state is %d\n", maciisi_state);
+#endif
+		restore_flags(flags);
+		return -EBUSY;
+	}
 
 	restore_flags(flags);
+
 	return 0;
 }
 
-static void
+static int
 maciisi_start(void)
 {
 	struct adb_request* req;
 	int status;
 
-	printk(KERN_DEBUG "maciisi_start called, state=%d, ifr=%x\n", maciisi_state, via[IFR]);
+#ifdef DEBUG_MACIISI_ADB
+	status = via[B] & (TIP | TREQ);
+
+	printk(KERN_DEBUG "maciisi_start called, state=%d, status=%x, ifr=%x\n", maciisi_state, status, via[IFR]);
+#endif
+
 	if (maciisi_state != idle) {
 		/* shouldn't happen */
 		printk(KERN_ERR "maciisi_start: maciisi_start called when driver busy!\n");
-		return;
+		return -EBUSY;
 	}
 
 	req = current_req;
 	if (req == NULL)
-		return;
+		return -EINVAL;
 
 	status = via[B] & (TIP|TREQ);
 	if (!(status & TREQ)) {
-		/* Bus is busy, set up for reading */
+#ifdef DEBUG_MACIISI_ADB
 		printk(KERN_DEBUG "maciisi_start: bus busy - aborting\n");
-		return;
+#endif
+		return -EBUSY;
 	}
 
 	/* Okay, send */
+#ifdef DEBUG_MACIISI_ADB
 	printk(KERN_DEBUG "maciisi_start: sending\n");
+#endif
 	/* Set state to active */
 	via[B] |= TIP;
 	/* ACK off */
 	via[B] &= ~TACK;
+	/* Delay */
+	udelay(ADB_DELAY);
 	/* Shift out and send */
 	via[ACR] |= SR_OUT;
 	via[SR] = req->data[0];
@@ -280,6 +393,8 @@
 	/* ACK on */
 	via[B] |= TACK;
 	maciisi_state = sending;
+
+	return 0;
 }
 
 void
@@ -292,6 +407,9 @@
 	if (via[IFR] & SR_INT) {
 		maciisi_interrupt(0, 0, 0);
 	}
+	else /* avoid calling this function too quickly in a loop */
+		udelay(ADB_DELAY);
+
 	restore_flags(flags);
 }
 
@@ -303,31 +421,44 @@
 {
 	int status;
 	struct adb_request *req;
-	static int dump_reply = 1;
+#ifdef DEBUG_MACIISI_ADB
+	static int dump_reply = 0;
+#endif
+	int i;
+	unsigned long flags;
+
+	save_flags(flags);
+	cli();
+
+	status = via[B] & (TIP|TREQ);
+#ifdef DEBUG_MACIISI_ADB
+	printk(KERN_DEBUG "state %d status %x ifr %x\n", maciisi_state, status, via[IFR]);
+#endif
 
 	if (!(via[IFR] & SR_INT)) {
 		/* Shouldn't happen, we hope */
-		printk(KERN_DEBUG "maciisi_interrupt: called without interrupt flag set\n");
+		printk(KERN_ERR "maciisi_interrupt: called without interrupt flag set\n");
+		restore_flags(flags);
 		return;
 	}
 
-	status = via[B] & (TIP|TREQ);
-	printk(KERN_DEBUG "state %d status %x ifr %x\n", maciisi_state, status, via[IFR]);
+	/* Clear the interrupt */
+	/* via[IFR] = SR_INT; */
 
  switch_start:
 	switch (maciisi_state) {
 	case idle:
-		printk(KERN_DEBUG "maciisi_interrupt: state=idle, status %x\n", status);
 		if (status & TIP)
-			printk(KERN_DEBUG "maciisi_interrupt: state is idle but TIP asserted!\n");
+			printk(KERN_ERR "maciisi_interrupt: state is idle but TIP asserted!\n");
 
-		udelay(ADB_DELAY);
+		if(!reading_reply)
+			udelay(ADB_DELAY);
 		/* Shift in */
 		via[ACR] &= ~SR_OUT;
  		/* Signal start of frame */
 		via[B] |= TIP;
 		/* Clear the interrupt (throw this value on the floor, it's useless) */
-		via[SR];
+		tmp = via[SR];
 		/* ACK adb chip, high-low */
 		via[B] |= TACK;
 		udelay(ADB_DELAY);
@@ -337,37 +468,39 @@
 		if (reading_reply) {
 			reply_ptr = current_req->reply;
 		} else {
-			printk(KERN_DEBUG "maciisi_interrupt: received unsolicited packet\n");
 			reply_ptr = maciisi_rbuf;
 		}
 		break;
 
 	case sending:
-		printk(KERN_DEBUG "maciisi_interrupt: state=sending, status=%x\n", status);
-		/* Clear interrupt */
-		via[SR];
+		/* via[SR]; */
 		/* Set ACK off */
 		via[B] &= ~TACK;
 		req = current_req;
 
 		if (!(status & TREQ)) {
 			/* collision */
-			printk(KERN_DEBUG "maciisi_interrupt: send collision\n");
+			printk(KERN_ERR "maciisi_interrupt: send collision\n");
 			/* Set idle and input */
-			via[B] &= ~TIP;
 			via[ACR] &= ~SR_OUT;
+			tmp = via[SR];
+			via[B] &= ~TIP;
 			/* Must re-send */
 			reading_reply = 0;
 			reply_len = 0;
 			maciisi_state = idle;
+			udelay(ADB_DELAY);
 			/* process this now, because the IFR has been cleared */
 			goto switch_start;
 		}
 
+		udelay(ADB_DELAY);
+
 		if (data_index >= req->nbytes) {
 			/* Sent the whole packet, put the bus back in idle state */
 			/* Shift in, we are about to read a reply (hopefully) */
 			via[ACR] &= ~SR_OUT;
+			tmp = via[SR];
 			/* End of frame */
 			via[B] &= ~TIP;
 			req->sent = 1;
@@ -380,13 +513,19 @@
 				current_req = req->next;
 				if (req->done)
 					(*req->done)(req);
+				/* Do any queued requests now */
+				i = maciisi_start();
+				if(i == 0 && need_sync) {
+					/* Packet needs to be synced */
+					maciisi_sync(current_req);
+				}
+				if(i != -EBUSY)
+					need_sync = 0;
 			}
 		} else {
 			/* Sending more stuff */
 			/* Shift out */
 			via[ACR] |= SR_OUT;
-			/* Delay */
-			udelay(ADB_DELAY);
 			/* Write */
 			via[SR] = req->data[data_index++];
 			/* Signal 'byte ready' */
@@ -395,18 +534,24 @@
 		break;
 
 	case reading:
-		printk(KERN_DEBUG "maciisi_interrupt: state=reading, status=%x\n", status);
 		/* Shift in */
-		via[ACR] &= ~SR_OUT;
+		/* via[ACR] &= ~SR_OUT; */ /* Not in 2.2 */
 		if (reply_len++ > 16) {
 			printk(KERN_ERR "maciisi_interrupt: reply too long, aborting read\n");
 			via[B] |= TACK;
 			udelay(ADB_DELAY);
 			via[B] &= ~(TACK|TIP);
 			maciisi_state = idle;
-			maciisi_start();
+			i = maciisi_start();
+			if(i == 0 && need_sync) {
+				/* Packet needs to be synced */
+				maciisi_sync(current_req);
+			}
+			if(i != -EBUSY)
+				need_sync = 0;
 			break;
 		}
+		/* Read data */
 		*reply_ptr++ = via[SR];
 		status = via[B] & (TIP|TREQ);
 		/* ACK on/off */
@@ -418,6 +563,8 @@
 		
 		/* end of frame */
 		via[B] &= ~TIP;
+		tmp = via[SR]; /* That's what happens in 2.2 */
+		udelay(ADB_DELAY); /* Give controller time to recover */
 
 		/* end of packet, deal with it */
 		if (reading_reply) {
@@ -434,6 +581,7 @@
 					memmove(req->reply, req->reply + 2, req->reply_len);
 				}
 			}
+#ifdef DEBUG_MACIISI_ADB
 			if (dump_reply) {
 				int i;
 				printk(KERN_DEBUG "maciisi_interrupt: reply is ");
@@ -441,6 +589,7 @@
 					printk(" %.2x", req->reply[i]);
 				printk("\n");
 			}
+#endif
 			req->complete = 1;
 			current_req = req->next;
 			if (req->done)
@@ -453,34 +602,62 @@
 		maciisi_state = idle;
 		status = via[B] & (TIP|TREQ);
 		if (!(status & TREQ)) {
-			/* Timeout?! */
+			/* Timeout?! More likely, another packet coming in already */
+#ifdef DEBUG_MACIISI_ADB
 			printk(KERN_DEBUG "extra data after packet: status %x ifr %x\n",
 			       status, via[IFR]);
-			maciisi_stfu();
+#endif
+#if 0
+			udelay(ADB_DELAY);
+			via[B] |= TIP;
+
+			maciisi_state = reading;
+			reading_reply = 0;
+			reply_ptr = maciisi_rbuf;
+#else
+			/* Process the packet now */
+			reading_reply = 0;
+			goto switch_start;
+#endif
+			/* We used to do this... but the controller might actually have data for us */
+			/* maciisi_stfu(); */
+		}
+		else {
+			/* Do any queued requests now if possible */
+			i = maciisi_start();
+			if(i == 0 && need_sync) {
+				/* Packet needs to be synced */
+				maciisi_sync(current_req);
+			}
+			if(i != -EBUSY)
+				need_sync = 0;
 		}
-		/* Do any queued requests now if possible */
-		maciisi_start();
 		break;
 
 	default:
 		printk("maciisi_interrupt: unknown maciisi_state %d?\n", maciisi_state);
 	}
+	restore_flags(flags);
 }
 
 static void
 maciisi_input(unsigned char *buf, int nb, struct pt_regs *regs)
 {
+#ifdef DEBUG_MACIISI_ADB
     int i;
+#endif
 
     switch (buf[0]) {
     case ADB_PACKET:
 	    adb_input(buf+2, nb-2, regs, buf[1] & 0x40);
 	    break;
     default:
+#ifdef DEBUG_MACIISI_ADB
 	    printk(KERN_DEBUG "data from IIsi ADB (%d bytes):", nb);
 	    for (i = 0; i < nb; ++i)
 		    printk(" %.2x", buf[i]);
 	    printk("\n");
-
+#endif
+	    break;
     }
 }