[PATCH] libata: modify ata_dev_try_classify

Make ata_dev_try_classify take @r_err to store tf error register value
on completion and return device class instead of directly manipulating
dev->class.  This is preparation for new reset mechanism.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 16 insertions, 14 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 4336fc889acd..1f78e246f5e0 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -830,6 +830,7 @@ unsigned int ata_dev_classify(const struct ata_taskfile *tf)
  *      ata_dev_try_classify - Parse returned ATA device signature
  *      @ap: ATA channel to examine
  *      @device: Device to examine (starting at zero)
+ *      @r_err: Value of error register on completion
  *
  *      After an event -- SRST, E.D.D., or SATA COMRESET -- occurs,
  *      an ATA/ATAPI-defined set of values is placed in the ATA
@@ -842,11 +843,14 @@ unsigned int ata_dev_classify(const struct ata_taskfile *tf)
  *
  *      LOCKING:
  *      caller.
+ *
+ *      RETURNS:
+ *      Device type - %ATA_DEV_ATA, %ATA_DEV_ATAPI or %ATA_DEV_NONE.
  */
 
-static u8 ata_dev_try_classify(struct ata_port *ap, unsigned int device)
+static unsigned int
+ata_dev_try_classify(struct ata_port *ap, unsigned int device, u8 *r_err)
 {
-        struct ata_device *dev = &ap->device[device];
         struct ata_taskfile tf;
         unsigned int class;
         u8 err;
@@ -857,8 +861,8 @@ static u8 ata_dev_try_classify(struct ata_port *ap, unsigned int device)
 
         ap->ops->tf_read(ap, &tf);
         err = tf.feature;
-
-        dev->class = ATA_DEV_NONE;
+        if (r_err)
+                *r_err = err;
 
         /* see if device passed diags */
         if (err == 1)
@@ -866,18 +870,16 @@ static u8 ata_dev_try_classify(struct ata_port *ap, unsigned int device)
         else if ((device == 0) && (err == 0x81))
                 /* do nothing */ ;
         else
-                return err;
+                return ATA_DEV_NONE;
 
-        /* determine if device if ATA or ATAPI */
+        /* determine if device is ATA or ATAPI */
         class = ata_dev_classify(&tf);
+
         if (class == ATA_DEV_UNKNOWN)
-                return err;
+                return ATA_DEV_NONE;
         if ((class == ATA_DEV_ATA) && (ata_chk_status(ap) == 0))
-                return err;
-
-        dev->class = class;
-
-        return err;
+                return ATA_DEV_NONE;
+        return class;
 }
 
 /**
@@ -2177,9 +2179,9 @@ void ata_bus_reset(struct ata_port *ap)
         /*
          * determine by signature whether we have ATA or ATAPI devices
          */
-        err = ata_dev_try_classify(ap, 0);
+        ap->device[0].class = ata_dev_try_classify(ap, 0, &err);
         if ((slave_possible) && (err != 0x81))
-                ata_dev_try_classify(ap, 1);
+                ap->device[1].class = ata_dev_try_classify(ap, 1, &err);
 
         /* re-enable interrupts */
         if (ap->ioaddr.ctl_addr)        /* FIXME: hack. create a hook instead */