[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>

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 4336fc889acd034b4b773843937ee9c6cf8ffc68..1f78e246f5e07577a4b621e7bd7d6abb8bfb0589 100644 (file)
--- 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 */