Revert "staging: vchiq_arm: Improve initial VCHIQ connect"

The commit 3e5def4 ("staging: vchiq_arm: Improve initial VCHIQ connect")
based on the assumption that in good case the VCHIQ connect always happen and
therefore the keep-alive thread is guaranteed to be woken up. This is wrong,
because in certain configurations there are no VCHIQ users and so the VCHIQ
connect never happen. So revert it.

Fixes: 3e5def4 ("staging: vchiq_arm: Improve initial VCHIQ connect")
Reported-by: Maíra Canal <[email protected]>
Closes: https://lore.kernel.org/linux-staging/[email protected]/
Cc: [email protected]
Signed-off-by: Stefan Wahren <[email protected]>
Reviewed-by: Maíra Canal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: lategoodbye

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c

@@ -97,6 +97,13 @@ struct vchiq_arm_state {
 	 * tracked separately with the state.
 	 */
 	int peer_use_count;
+
+	/*
+	 * Flag to indicate that the first vchiq connect has made it through.
+	 * This means that both sides should be fully ready, and we should
+	 * be able to suspend after this point.
+	 */
+	int first_connect;
 };
 
 static int
@@ -1329,19 +1336,26 @@ vchiq_check_service(struct vchiq_service *service)
 	return ret;
 }
 
-void vchiq_platform_connected(struct vchiq_state *state)
-{
-	struct vchiq_arm_state *arm_state = vchiq_platform_get_arm_state(state);
-
-	wake_up_process(arm_state->ka_thread);
-}
-
 void vchiq_platform_conn_state_changed(struct vchiq_state *state,
 				       enum vchiq_connstate oldstate,
 				       enum vchiq_connstate newstate)
 {
+	struct vchiq_arm_state *arm_state = vchiq_platform_get_arm_state(state);
+
 	dev_dbg(state->dev, "suspend: %d: %s->%s\n",
 		state->id, get_conn_state_name(oldstate), get_conn_state_name(newstate));
+	if (state->conn_state != VCHIQ_CONNSTATE_CONNECTED)
+		return;
+
+	write_lock_bh(&arm_state->susp_res_lock);
+	if (arm_state->first_connect) {
+		write_unlock_bh(&arm_state->susp_res_lock);
+		return;
+	}
+
+	arm_state->first_connect = 1;
+	write_unlock_bh(&arm_state->susp_res_lock);
+	wake_up_process(arm_state->ka_thread);
 }
 
 static const struct of_device_id vchiq_of_match[] = {

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c

@@ -3343,7 +3343,6 @@ vchiq_connect_internal(struct vchiq_state *state, struct vchiq_instance *instanc
 			return -EAGAIN;
 
 		vchiq_set_conn_state(state, VCHIQ_CONNSTATE_CONNECTED);
-		vchiq_platform_connected(state);
 		complete(&state->connect);
 	}
 

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.h

@@ -575,8 +575,6 @@ int vchiq_send_remote_use(struct vchiq_state *state);
 
 int vchiq_send_remote_use_active(struct vchiq_state *state);
 
-void vchiq_platform_connected(struct vchiq_state *state);
-
 void vchiq_platform_conn_state_changed(struct vchiq_state *state,
 				       enum vchiq_connstate oldstate,
 				  enum vchiq_connstate newstate);