[PATCH] libata CHS: reread device identify info (revise #6)

problem:
      id[53-58] might be changed after initializing device CHS settings.

changes:
    - call ata_dev_reread_id() to reread the identify device info,
      after initializing device CHS settings.

Signed-off-by: Albert Lee <albertcc@tw.ibm.com>

============
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 64 insertions, 1 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 19d3d717faf6..175d4646333d 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -63,6 +63,7 @@
 static unsigned int ata_busy_sleep (struct ata_port *ap,
                                     unsigned long tmout_pat,
                                     unsigned long tmout);
+static void ata_dev_reread_id(struct ata_port *ap, struct ata_device *dev);
 static void ata_dev_init_params(struct ata_port *ap, struct ata_device *dev);
 static void ata_set_mode(struct ata_port *ap);
 static void ata_dev_set_xfermode(struct ata_port *ap, struct ata_device *dev);
@@ -1240,9 +1241,15 @@ retry:
                  * anything else..
                  * Some drives were very specific about that exact sequence.
                  */
-                if (major_version < 4 || (!ata_id_has_lba(dev->id)))
+                if (major_version < 4 || (!ata_id_has_lba(dev->id))) {
                         ata_dev_init_params(ap, dev);
 
+                        /* current CHS translation info (id[53-58]) might be
+                         * changed. reread the identify device info.
+                         */
+                        ata_dev_reread_id(ap, dev);
+                }
+
                 if (ata_id_has_lba(dev->id)) {
                         dev->flags |= ATA_DFLAG_LBA;
 
@@ -2151,6 +2158,62 @@ static void ata_dev_set_xfermode(struct ata_port *ap, struct ata_device *dev)
 }
 
 /**
+ *      ata_dev_reread_id - Reread the device identify device info
+ *      @ap: port where the device is
+ *      @dev: device to reread the identify device info
+ *
+ *      LOCKING:
+ */
+
+static void ata_dev_reread_id(struct ata_port *ap, struct ata_device *dev)
+{
+        DECLARE_COMPLETION(wait);
+        struct ata_queued_cmd *qc;
+        unsigned long flags;
+        int rc;
+
+        qc = ata_qc_new_init(ap, dev);
+        BUG_ON(qc == NULL);
+
+        ata_sg_init_one(qc, dev->id, sizeof(dev->id));
+        qc->dma_dir = DMA_FROM_DEVICE;
+
+        if (dev->class == ATA_DEV_ATA) {
+                qc->tf.command = ATA_CMD_ID_ATA;
+                DPRINTK("do ATA identify\n");
+        } else {
+                qc->tf.command = ATA_CMD_ID_ATAPI;
+                DPRINTK("do ATAPI identify\n");
+        }
+
+        qc->tf.flags |= ATA_TFLAG_DEVICE;
+        qc->tf.protocol = ATA_PROT_PIO;
+        qc->nsect = 1;
+
+        qc->waiting = &wait;
+        qc->complete_fn = ata_qc_complete_noop;
+
+        spin_lock_irqsave(&ap->host_set->lock, flags);
+        rc = ata_qc_issue(qc);
+        spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+        if (rc)
+                goto err_out;
+
+        wait_for_completion(&wait);
+
+        swap_buf_le16(dev->id, ATA_ID_WORDS);
+
+        ata_dump_id(dev);
+
+        DPRINTK("EXIT\n");
+
+        return;
+err_out:
+        ata_port_disable(ap);
+}
+
+/**
  *      ata_dev_init_params - Issue INIT DEV PARAMS command
  *      @ap: Port associated with device @dev
  *      @dev: Device to which command will be sent