From 5eb95f141948cd44ea4d01d9922de2b99589bc42 Mon Sep 17 00:00:00 2001
From: Laurent Vivier <Laurent@lvivier.info>
Date: Mon, 30 Oct 2006 21:52:58 +0000
Subject: [PATCH] Wait bus is not busy

---
 libscsi/scsi_command.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/libscsi/scsi_command.c b/libscsi/scsi_command.c
index 4556bf7..a8e7869 100644
--- a/libscsi/scsi_command.c
+++ b/libscsi/scsi_command.c
@@ -11,17 +11,45 @@
 #include <macos/types.h>
 #include <macos/errors.h>
 #include <macos/scsi.h>
+#include <macos/lowmem.h>
 
 #include "libscsi.h"
 
 #define COMPLETION_TIMEOUT	300
 
+#define SCSI_BUSY		(1 << 6)
+#define SCSI_SEL		(1 << 1)
+
+static inline int scsi_busy(void)
+{
+	return (SCSIStat() & (SCSI_BUSY | SCSI_SEL)) != 0;
+}
+
+static inline int scsi_wait_bus()
+{
+	int timeout;
+
+	timeout = Ticks + 300;
+
+	while (scsi_busy())
+		if (Ticks > timeout)
+			return scsiBusy;
+	return noErr;
+}
+
 int scsi_command(int target, char* cdb, int count, TIB_t* tib)
 {
 	int err;
 	short stat;
 	short message;
 
+	err = scsi_wait_bus();
+	if (err != noErr)
+	{
+		printf("SCSI bus is busy\n");
+		return err;
+	}
+
 	err = SCSIGet();
 	if (err != noErr) 
 	{