Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  libata: Power off empty ports
  libata-pmp: add support for Thermaltake BlackX Duet esata drive dock
  ATA: Don't powerdown Compaq Triflex IDE device on suspend
  libata: Use Maximum Write Same Length to report discard size limit
  drivers/ata/acard-ahci.c: fix enum warning
  pata_at91: SMC settings calculation bugfixes, support for t6z and IORDY
  libata-sff: prevent irq descriptions for dummy ports
  pata_cm64x: fix boot crash on parisc

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 76c3c15cb1e6..736bee5dafeb 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -3619,8 +3619,14 @@ int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
                 scontrol |= (0x2 << 8);
                 break;
         case ATA_LPM_MIN_POWER:
-                /* no restrictions on LPM transitions */
-                scontrol &= ~(0x3 << 8);
+                if (ata_link_nr_enabled(link) > 0)
+                        /* no restrictions on LPM transitions */
+                        scontrol &= ~(0x3 << 8);
+                else {
+                        /* empty port, power off */
+                        scontrol &= ~0xf;
+                        scontrol |= (0x1 << 2);
+                }
                 break;
         default:
                 WARN_ON(1);