Merge branch 'e1000-fixes' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik...

[pandora-kernel.git] / drivers / s390 / cio / device_status.c

diff --git a/drivers/s390/cio/device_status.c b/drivers/s390/cio/device_status.c
index 6b1caea..aa96e67 100644 (file)
--- a/drivers/s390/cio/device_status.c
+++ b/drivers/s390/cio/device_status.c
@@ -221,6 +221,14 @@ ccw_device_accumulate_irb(struct ccw_device *cdev, struct irb *irb)
 
        cdev_irb = &cdev->private->irb;
 
+       /*
+        * If the clear function had been performed, all formerly pending
+        * status at the subchannel has been cleared and we must not pass
+        * intermediate accumulated status to the device driver.
+        */
+       if (irb->scsw.fctl & SCSW_FCTL_CLEAR_FUNC)
+               memset(&cdev->private->irb, 0, sizeof(struct irb));
+
        /* Copy bits which are valid only for the start function. */
        if (irb->scsw.fctl & SCSW_FCTL_START_FUNC) {
                /* Copy key. */
@@ -263,7 +271,11 @@ ccw_device_accumulate_irb(struct ccw_device *cdev, struct irb *irb)
                cdev_irb->scsw.cpa = irb->scsw.cpa;
        /* Accumulate device status, but not the device busy flag. */
        cdev_irb->scsw.dstat &= ~DEV_STAT_BUSY;
-       cdev_irb->scsw.dstat |= irb->scsw.dstat;
+       /* dstat is not always valid. */
+       if (irb->scsw.stctl &
+           (SCSW_STCTL_PRIM_STATUS | SCSW_STCTL_SEC_STATUS
+            | SCSW_STCTL_INTER_STATUS | SCSW_STCTL_ALERT_STATUS))
+               cdev_irb->scsw.dstat |= irb->scsw.dstat;
        /* Accumulate subchannel status. */
        cdev_irb->scsw.cstat |= irb->scsw.cstat;
        /* Copy residual count if it is valid. */