2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-13 07:44:00 +08:00

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>
This commit is contained in:
Kristen Carlson Accardi 2011-03-04 10:24:11 -08:00 committed by Jeff Garzik
parent 0afc6f5ba9
commit 8a745f1f39
3 changed files with 10 additions and 3 deletions

View File

@ -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);

View File

@ -3423,7 +3423,7 @@ fail:
return rc;
}
static int ata_link_nr_enabled(struct ata_link *link)
int ata_link_nr_enabled(struct ata_link *link)
{
struct ata_device *dev;
int cnt = 0;

View File

@ -1151,6 +1151,7 @@ extern void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
ata_postreset_fn_t postreset);
extern void ata_std_error_handler(struct ata_port *ap);
extern int ata_link_nr_enabled(struct ata_link *link);
/*
* Base operations to inherit from and initializers for sht