1 files changed, 47 insertions, 8 deletions

diff --git a/freebsd/sys/dev/iicbus/iiconf.c b/freebsd/sys/dev/iicbus/iiconf.c
index afdce118..c4926852 100644
--- a/freebsd/sys/dev/iicbus/iiconf.c
+++ b/freebsd/sys/dev/iicbus/iiconf.c
@@ -44,6 +44,18 @@ __FBSDID("$FreeBSD$");
 #include <rtems/bsd/local/iicbus_if.h>
 
 /*
+ * Encode a system errno value into the IIC_Exxxxx space by setting the
+ * IIC_ERRNO marker bit, so that iic2errno() can turn it back into a plain
+ * system errno value later.  This lets controller- and bus-layer code get
+ * important system errno values (such as EINTR/ERESTART) back to the caller.
+ */
+int
+errno2iic(int error)
+{
+	return ((error == 0) ? 0 : error | IIC_ERRNO);
+}
+
+/*
  * Translate IIC_Exxxxx status values to vaguely-equivelent errno values.
  */
 int
@@ -61,7 +73,22 @@ iic2errno(int iic_status)
 	case IIC_ENOTSUPP:      return (EOPNOTSUPP);
 	case IIC_ENOADDR:       return (EADDRNOTAVAIL);
 	case IIC_ERESOURCE:     return (ENOMEM);
-	default:                return (EIO);
+	default:
+		/*
+		 * If the high bit is set, that means it's a system errno value
+		 * that was encoded into the IIC_Exxxxxx space by setting the
+		 * IIC_ERRNO marker bit.  If lots of high-order bits are set,
+		 * then it's one of the negative pseudo-errors such as ERESTART
+		 * and we return it as-is.  Otherwise it's a plain "small
+		 * positive integer" errno, so just remove the IIC_ERRNO marker
+		 * bit.  If it's some unknown number without the high bit set,
+		 * there isn't much we can do except call it an I/O error.
+		 */
+		if ((iic_status & IIC_ERRNO) == 0)
+			return (EIO);
+		if ((iic_status & 0xFFFF0000) != 0)
+			return (iic_status);
+		return (iic_status & ~IIC_ERRNO);
 	}
 }
 
@@ -99,7 +126,7 @@ iicbus_poll(struct iicbus_softc *sc, int how)
 		return (IIC_EBUSBSY);
 	}
 
-	return (error);
+	return (errno2iic(error));
 }
 
 /*
@@ -130,6 +157,18 @@ iicbus_request_bus(device_t bus, device_t dev, int how)
 		++sc->owncount;
 		if (sc->owner == NULL) {
 			sc->owner = dev;
+			/*
+			 * Mark the device busy while it owns the bus, to
+			 * prevent detaching the device, bus, or hardware
+			 * controller, until ownership is relinquished.  If the
+			 * device is doing IO from its probe method before
+			 * attaching, it cannot be busied; mark the bus busy.
+			 */
+			if (device_get_state(dev) < DS_ATTACHING)
+				sc->busydev = bus;
+			else
+				sc->busydev = dev;
+			device_busy(sc->busydev);
 			/* 
 			 * Drop the lock around the call to the bus driver, it
 			 * should be allowed to sleep in the IIC_WAIT case.
@@ -146,6 +185,7 @@ iicbus_request_bus(device_t bus, device_t dev, int how)
 				sc->owner = NULL;
 				sc->owncount = 0;
 				wakeup_one(sc);
+				device_unbusy(sc->busydev);
 			}
 		}
 	}
@@ -179,6 +219,7 @@ iicbus_release_bus(device_t bus, device_t dev)
 		IICBUS_LOCK(sc);
 		sc->owner = NULL;
 		wakeup_one(sc);
+		device_unbusy(sc->busydev);
 	}
 	IICBUS_UNLOCK(sc);
 	return (0);
@@ -422,7 +463,7 @@ iicbus_transfer_gen(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
 {
 	int i, error, lenread, lenwrote, nkid, rpstart, addr;
 	device_t *children, bus;
-	bool nostop, started;
+	bool started;
 
 	if ((error = device_get_children(dev, &children, &nkid)) != 0)
 		return (IIC_ERESOURCE);
@@ -433,7 +474,6 @@ iicbus_transfer_gen(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
 	bus = children[0];
 	rpstart = 0;
 	free(children, M_TEMP);
-	nostop = iicbus_get_nostop(dev);
 	started = false;
 	for (i = 0, error = 0; i < nmsgs && error == 0; i++) {
 		addr = msgs[i].slave;
@@ -461,12 +501,11 @@ iicbus_transfer_gen(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
 		if (error != 0)
 			break;
 
-		if ((msgs[i].flags & IIC_M_NOSTOP) != 0 ||
-		    (nostop && i + 1 < nmsgs)) {
-			rpstart = 1;	/* Next message gets repeated start */
-		} else {
+		if (!(msgs[i].flags & IIC_M_NOSTOP)) {
 			rpstart = 0;
 			iicbus_stop(bus);
+		} else {
+			rpstart = 1;	/* Next message gets repeated start */
 		}
 	}
 	if (error != 0 && started)