[SCSI] libsas: Add a sysfs knob to enable/disable a phy

This patch lets a user arbitrarily enable or disable a phy via sysfs.
Potential applications include shutting down a phy to replace one
lane of wide port, and (more importantly) providing a method for the
libata SATL to control the phy.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

2 files changed, 5 insertions, 0 deletions

diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h
index da96bcfb9e4..0689d6682aa 100644
--- a/include/scsi/libsas.h
+++ b/include/scsi/libsas.h
@@ -614,6 +614,9 @@ struct sas_domain_function_template {
 extern int sas_register_ha(struct sas_ha_struct *);
 extern int sas_unregister_ha(struct sas_ha_struct *);
 
+int sas_set_phy_speed(struct sas_phy *phy,
+                      struct sas_phy_linkrates *rates);
+int sas_phy_enable(struct sas_phy *phy, int enabled);
 int sas_phy_reset(struct sas_phy *phy, int hard_reset);
 extern int sas_queuecommand(struct scsi_cmnd *,
                      void (*scsi_done)(struct scsi_cmnd *));
diff --git a/include/scsi/scsi_transport_sas.h b/include/scsi/scsi_transport_sas.h
index 59633a82de4..45d58598c3e 100644
--- a/include/scsi/scsi_transport_sas.h
+++ b/include/scsi/scsi_transport_sas.h
@@ -54,6 +54,7 @@ struct sas_identify {
 struct sas_phy {
         struct device           dev;
         int                     number;
+        int                     enabled;
 
         /* phy identification */
         struct sas_identify     identify;
@@ -163,6 +164,7 @@ struct sas_function_template {
         int (*get_enclosure_identifier)(struct sas_rphy *, u64 *);
         int (*get_bay_identifier)(struct sas_rphy *);
         int (*phy_reset)(struct sas_phy *, int);
+        int (*phy_enable)(struct sas_phy *, int);
         int (*set_phy_speed)(struct sas_phy *, struct sas_phy_linkrates *);
 };