[SCSI] mpt2sas: Add a module parameter that permits overriding protection capabilities

Add a parameter that allows the host protection capabilities mask to be
provided at module load time.

Signed-off-by: Martin K. Petersen <[e-mail]>
Acked-by: "Sreekanth Reddy" <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/mpt2sas/mpt2sas_scsih.c

···
 module_param(disable_discovery, int, 0);
 MODULE_PARM_DESC(disable_discovery, " disable discovery ");
 
+/* permit overriding the host protection capabilities mask (EEDP/T10 PI) */
+static int prot_mask = 0;
+module_param(prot_mask, int, 0);
+MODULE_PARM_DESC(prot_mask, " host protection capabilities mask, def=7 ");
+
 /**
  * struct sense_info - common structure for obtaining sense keys
  * @skey: sense key
···
 		goto out_add_shost_fail;
 	}
 
-	scsi_host_set_prot(shost, SHOST_DIF_TYPE1_PROTECTION
-	    | SHOST_DIF_TYPE2_PROTECTION | SHOST_DIF_TYPE3_PROTECTION);
+	/* register EEDP capabilities with SCSI layer */
+	if (prot_mask)
+		scsi_host_set_prot(shost, prot_mask);
+	else
+		scsi_host_set_prot(shost, SHOST_DIF_TYPE1_PROTECTION
+				   | SHOST_DIF_TYPE2_PROTECTION
+				   | SHOST_DIF_TYPE3_PROTECTION);
+
 	scsi_host_set_guard(shost, SHOST_DIX_GUARD_CRC);
 
 	/* event thread */