isci: Handle all suspending TC completions

Add comprehensive decode for all TC completions that generate RNC
suspensions.

Note that this commit also removes unconditional resumptions of ATAPI
devices when in the SCI_STP_DEV_ATAPI_ERROR state, and STP devices
when in the SCI_STP_DEV_IDLE state. This is because the SCI_STP_DEV_IDLE
and SCI_STP_DEV_ATAPI state entry functions manage the RNC resumption.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 51 insertions, 23 deletions

diff --git a/drivers/scsi/isci/remote_node_context.c b/drivers/scsi/isci/remote_node_context.c
index 3e84975..f180c72 100644
--- a/drivers/scsi/isci/remote_node_context.c
+++ b/drivers/scsi/isci/remote_node_context.c
@@ -367,6 +367,7 @@ enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_con
 							   u32 event_code)
 {
 	enum scis_sds_remote_node_context_states state;
+	u32 next_state;
 
 	state = sci_rnc->sm.current_state_id;
 	switch (state) {
@@ -425,11 +426,11 @@ enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_con
 		switch (scu_get_event_type(event_code)) {
 		case SCU_EVENT_TL_RNC_SUSPEND_TX:
 			sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
-			sci_rnc->suspension_code = scu_get_event_specifier(event_code);
+			sci_rnc->suspend_type = scu_get_event_type(event_code);
 			break;
 		case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
 			sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
-			sci_rnc->suspension_code = scu_get_event_specifier(event_code);
+			sci_rnc->suspend_type = scu_get_event_type(event_code);
 			break;
 		default:
 			goto out;
@@ -438,16 +439,16 @@ enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_con
 	case SCI_RNC_AWAIT_SUSPENSION:
 		switch (scu_get_event_type(event_code)) {
 		case SCU_EVENT_TL_RNC_SUSPEND_TX:
-			sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
-			sci_rnc->suspension_code = scu_get_event_specifier(event_code);
+			next_state = SCI_RNC_TX_SUSPENDED;
 			break;
 		case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
-			sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
-			sci_rnc->suspension_code = scu_get_event_specifier(event_code);
+			next_state = SCI_RNC_TX_RX_SUSPENDED;
 			break;
 		default:
 			goto out;
 		}
+		if (sci_rnc->suspend_type == scu_get_event_type(event_code))
+			sci_change_state(&sci_rnc->sm, next_state);
 		break;
 	default:
 		dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
@@ -502,33 +503,60 @@ enum sci_status sci_remote_node_context_destruct(struct sci_remote_node_context
 	}
 }
 
-enum sci_status sci_remote_node_context_suspend(struct sci_remote_node_context *sci_rnc,
-						     u32 suspend_type,
-						     scics_sds_remote_node_context_callback cb_fn,
-						     void *cb_p)
+enum sci_status sci_remote_node_context_suspend(
+			struct sci_remote_node_context *sci_rnc,
+			enum sci_remote_node_suspension_reasons suspend_reason,
+			u32 suspend_type,
+			scics_sds_remote_node_context_callback cb_fn,
+			void *cb_p)
 {
-	enum scis_sds_remote_node_context_states state;
+	enum scis_sds_remote_node_context_states state
+		= sci_rnc->sm.current_state_id;
+	struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
+	enum sci_status status = SCI_FAILURE_INVALID_STATE;
 
-	state = sci_rnc->sm.current_state_id;
-	if (state != SCI_RNC_READY) {
+	/* Disable automatic state continuations if explicitly suspending. */
+	if (suspend_reason == SCI_SOFTWARE_SUSPENSION)
+		sci_rnc->destination_state
+			= SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_UNSPECIFIED;
+	switch (state) {
+	case SCI_RNC_READY:
+		break;
+	case SCI_RNC_TX_SUSPENDED:
+		if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX)
+			status = SCI_SUCCESS;
+		break;
+	case SCI_RNC_TX_RX_SUSPENDED:
+		if (suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
+			status = SCI_SUCCESS;
+		break;
+	case SCI_RNC_AWAIT_SUSPENSION:
+		if ((sci_rnc->suspend_type == SCU_EVENT_TL_RNC_SUSPEND_TX_RX)
+		    || (suspend_type == sci_rnc->suspend_type))
+			return SCI_SUCCESS;
+		break;
+	default:
 		dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
 			 "%s: invalid state %s\n", __func__,
 			 rnc_state_name(state));
 		return SCI_FAILURE_INVALID_STATE;
 	}
+	sci_rnc->user_callback = cb_fn;
+	sci_rnc->user_cookie   = cb_p;
+	sci_rnc->suspend_type  = suspend_type;
 
-	sci_rnc->user_callback   = cb_fn;
-	sci_rnc->user_cookie     = cb_p;
-	sci_rnc->suspension_code = suspend_type;
-
-	if (suspend_type == SCI_SOFTWARE_SUSPENSION) {
-		sci_remote_device_post_request(rnc_to_dev(sci_rnc),
-						    SCU_CONTEXT_COMMAND_POST_RNC_SUSPEND_TX);
-		isci_dev_set_hang_detection_timeout(rnc_to_dev(sci_rnc),
-						    0x00000001);
+	if (status == SCI_SUCCESS) { /* Already in the destination state? */
+		sci_remote_node_context_notify_user(sci_rnc);
+		return SCI_SUCCESS;
+	}
+	if (suspend_reason == SCI_SOFTWARE_SUSPENSION) {
+		isci_dev_set_hang_detection_timeout(idev, 0x00000001);
+		sci_remote_device_post_request(
+			idev, SCI_SOFTWARE_SUSPEND_CMD);
 	}
+	if (state != SCI_RNC_AWAIT_SUSPENSION)
+		sci_change_state(&sci_rnc->sm, SCI_RNC_AWAIT_SUSPENSION);
 
-	sci_change_state(&sci_rnc->sm, SCI_RNC_AWAIT_SUSPENSION);
 	return SCI_SUCCESS;
 }