As the default low power policy applies to more chipsets and drives, it's
important to make sure that drives actually support the policy that a user
selected in their kernel configuration.
If the drive doesn't support slumber, don't let the default policy for the
ATA port be `min_power` or `min_power_with_partial`.
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v2->v3:
* Fix typo
* Try to reset to CONFIG_SATA_LPM_POLICY unless that's too aggressive
then take MED_POWER.
drivers/ata/libata-sata.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index 044a16daa2d4..b41de7e03dce 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -13,6 +13,7 @@
#include <scsi/scsi_device.h>
#include <linux/libata.h>
+#include "ahci.h"
#include "libata.h"
#include "libata-transport.h"
@@ -368,10 +369,21 @@ int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
bool spm_wakeup)
{
struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_port *ap = link->ap;
+ struct ahci_host_priv *hpriv;
bool woken_up = false;
u32 scontrol;
int rc;
+ hpriv = ap->host->private_data;
+ if (policy >= ATA_LPM_MIN_POWER_WITH_PARTIAL &&
+ !(hpriv->cap & HOST_CAP_SSC)) {
+ policy = (CONFIG_SATA_LPM_POLICY < ATA_LPM_MIN_POWER_WITH_PARTIAL) ?
+ CONFIG_SATA_LPM_POLICY : ATA_LPM_MED_POWER;
+ dev_warn(ap->host->dev,
+ "This drive doesn't support slumber; resetting policy to %d\n", policy);
+ }
+
rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
if (rc)
return rc;
--
2.34.1
