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| author | Kristen Carlson Accardi <kristen@linux.intel.com> | 2011-03-04 10:24:11 -0800 |
|---|---|---|
| committer | Jeff Garzik <jgarzik@pobox.com> | 2011-05-19 20:50:53 -0400 |
| commit | 8a745f1f39b7a20047a362b67ce9151c07d14440 (patch) | |
| tree | f8f08be7a284d195f30a8b2e6fc63b714e4f7f21 /drivers/ata/libata-core.c | |
| parent | 0afc6f5ba95419fd505e60637f7645425f16e407 (diff) | |
| download | linux-8a745f1f39b7a20047a362b67ce9151c07d14440.tar.gz linux-8a745f1f39b7a20047a362b67ce9151c07d14440.tar.bz2 linux-8a745f1f39b7a20047a362b67ce9151c07d14440.zip | |
libata: Power off empty ports
Give users the option of completely powering off unoccupied
SATA ports using the existing min_power link_power_management_policy
option. When the use selects this option on an empty port, we
will power the port off by setting DET to off. For occupied ports,
behavior is unchanged.
Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Diffstat (limited to 'drivers/ata/libata-core.c')
| -rw-r--r-- | drivers/ata/libata-core.c | 10 |
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); |