From: Doug Berger <opendmb@gmail.com>
Date: Wed, 21 Jun 2017 16:20:12 -0700
Subject: [PATCH] libata: Add the AHCI_HFLAG_YES_ALPM flag
Git-commit: ef0da1bf767d9e557c6375c7066717eead54cb15
Patch-Mainline: v4.13-rc1
References: 1079088
Some hardware is capable of supporting Aggresive Link Power Management
even though it is not indicated by the Host Capability register.
This commit adds the AHCI_HFLAG_YES_ALPM flag to the AHCI library to
allow indication of this quirk when the Host Capability register is
Read Only and therefore cannot be changed.
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Hannes Reinecke <hare@suse.com>
---
drivers/ata/ahci.h | 1 +
drivers/ata/libahci.c | 5 +++++
2 files changed, 6 insertions(+)
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 30f67a1a4f54..ee176e4af97a 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -248,6 +248,7 @@ enum {
AHCI_HFLAG_MULTI_MSI = 0,
#endif
AHCI_HFLAG_WAKE_BEFORE_STOP = (1 << 22), /* wake before DMA stop */
+ AHCI_HFLAG_YES_ALPM = (1 << 23), /* force ALPM cap on */
/* ap->flags bits */
diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index b3a685ad9b87..4462f8a8cf2c 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -504,6 +504,11 @@ void ahci_save_initial_config(struct device *dev, struct ahci_host_priv *hpriv)
cap &= ~HOST_CAP_FBS;
}
+ if (!(cap & HOST_CAP_ALPM) && (hpriv->flags & AHCI_HFLAG_YES_ALPM)) {
+ dev_info(dev, "controller can do ALPM, turning on CAP_ALPM\n");
+ cap |= HOST_CAP_ALPM;
+ }
+
if (hpriv->force_port_map && port_map != hpriv->force_port_map) {
dev_info(dev, "forcing port_map 0x%x -> 0x%x\n",
port_map, hpriv->force_port_map);
--
2.12.3