libata: check onlineness before using SPD in sata_down_spd_limit()

sata_down_spd_limit() should check whether the link is online before
using the SPD value to determine how to limit the link speed.  Factor
out onlineness test and test it from sata_down_spd_limit().

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index af60d27..d006e5c 100644 (file)
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -164,6 +164,11 @@ MODULE_LICENSE("GPL");
 MODULE_VERSION(DRV_VERSION);
 
 
+static bool ata_sstatus_online(u32 sstatus)
+{
+       return (sstatus & 0xf) == 0x3;
+}
+
 /**
  *     ata_link_next - link iteration helper
  *     @link: the previous link, NULL to start
@@ -2891,7 +2896,7 @@ int sata_down_spd_limit(struct ata_link *link)
         * If not, use cached value in link->sata_spd.
         */
        rc = sata_scr_read(link, SCR_STATUS, &sstatus);
-       if (rc == 0)
+       if (rc == 0 && ata_sstatus_online(sstatus))
                spd = (sstatus >> 4) & 0xf;
        else
                spd = link->sata_spd;
@@ -5162,7 +5167,7 @@ bool ata_phys_link_online(struct ata_link *link)
        u32 sstatus;
 
        if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
-           (sstatus & 0xf) == 0x3)
+           ata_sstatus_online(sstatus))
                return true;
        return false;
 }
@@ -5186,7 +5191,7 @@ bool ata_phys_link_offline(struct ata_link *link)
        u32 sstatus;
 
        if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
-           (sstatus & 0xf) != 0x3)
+           !ata_sstatus_online(sstatus))
                return true;
        return false;
 }