libata: implement PMP helpers

Implement helpers to test whether PMP is supported, attached and
determine pmp number to use when issuing SRST to a link.  While at it,
move ata_is_host_link() so that it's together with the two new PMP
helpers.

This change simplifies LLDs and helps making PMP support optional.

Signed-off-by: Tejun Heo <htejun@gmail.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index a70881c408e5..fedf62de9460 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -2617,7 +2617,7 @@ static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
 
 static struct ata_device *ata_find_dev(struct ata_port *ap, int devno)
 {
-        if (ap->nr_pmp_links == 0) {
+        if (!sata_pmp_attached(ap)) {
                 if (likely(devno < ata_link_max_devices(&ap->link)))
                         return &ap->link.device[devno];
         } else {
@@ -2634,7 +2634,7 @@ static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
         int devno;
 
         /* skip commands not addressed to targets we simulate */
-        if (ap->nr_pmp_links == 0) {
+        if (!sata_pmp_attached(ap)) {
                 if (unlikely(scsidev->channel || scsidev->lun))
                         return NULL;
                 devno = scsidev->id;
@@ -3492,7 +3492,7 @@ static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
         if (lun != SCAN_WILD_CARD && lun)
                 return -EINVAL;
 
-        if (ap->nr_pmp_links == 0) {
+        if (!sata_pmp_attached(ap)) {
                 if (channel != SCAN_WILD_CARD && channel)
                         return -EINVAL;
                 devno = id;