pbio/servo: Return PBIO_ERROR_NO_DEV on stopped controller.

In practice, the only way this can happen is by unplugging motors. Returning
"no device" is more helpful than a permission error.

Author: laurensvalk

lib/pbio/src/drivebase.c

@@ -409,7 +409,7 @@ pbio_error_t pbio_drivebase_stop(pbio_drivebase_t *db, pbio_control_on_completio
 
     // Don't allow new user command if update loop not registered.
     if (!pbio_drivebase_update_loop_is_running(db)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // We're asked to stop, so continuing makes no sense.
@@ -555,7 +555,7 @@ static pbio_error_t pbio_drivebase_drive_relative(pbio_drivebase_t *db, int32_t
 
     // Don't allow new user command if update loop not registered.
     if (!pbio_drivebase_update_loop_is_running(db)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Stop servo control in case it was running.
@@ -666,7 +666,7 @@ pbio_error_t pbio_drivebase_drive_curve(pbio_drivebase_t *db, int32_t radius, in
 pbio_error_t pbio_drivebase_drive_turn(pbio_drivebase_t *db, int32_t angle, bool absolute, pbio_control_on_completion_t on_completion) {
     // Don't allow new user command if update loop not registered.
     if (!pbio_drivebase_update_loop_is_running(db)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Stop servo control in case it was running.
@@ -799,7 +799,7 @@ static pbio_error_t pbio_drivebase_drive_time_common(pbio_drivebase_t *db, int32
 
     // Don't allow new user command if update loop not registered.
     if (!pbio_drivebase_update_loop_is_running(db)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Stop servo control in case it was running.
@@ -1043,7 +1043,7 @@ pbio_error_t pbio_drivebase_set_drive_settings(pbio_drivebase_t *db, int32_t dri
  * @param [in]  db              The servo instance.
  * @param [out] stalled         True if stalled, false if not.
  * @param [out] stall_duration  For how long it has been stalled (ms).
- * @return                      Error code. ::PBIO_ERROR_INVALID_OP if update
+ * @return                      Error code. ::PBIO_ERROR_NO_DEV if update
  *                              loop not running, else ::PBIO_SUCCESS
  */
 pbio_error_t pbio_drivebase_is_stalled(pbio_drivebase_t *db, bool *stalled, uint32_t *stall_duration) {
@@ -1052,7 +1052,7 @@ pbio_error_t pbio_drivebase_is_stalled(pbio_drivebase_t *db, bool *stalled, uint
     if (!pbio_drivebase_update_loop_is_running(db)) {
         *stalled = false;
         *stall_duration = 0;
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     pbio_error_t err;

lib/pbio/src/servo.c

@@ -463,7 +463,7 @@ pbio_error_t pbio_servo_get_state_user(pbio_servo_t *srv, int32_t *angle, int32_
 
     // Don't allow user command if update loop not registered.
     if (!pbio_servo_update_loop_is_running(srv)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Get servo state.
@@ -536,7 +536,7 @@ pbio_error_t pbio_servo_stop(pbio_servo_t *srv, pbio_control_on_completion_t on_
 
     // Don't allow new user command if update loop not registered.
     if (!pbio_servo_update_loop_is_running(srv)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Stop parent object that uses this motor, if any.
@@ -591,7 +591,7 @@ static pbio_error_t pbio_servo_run_time_common(pbio_servo_t *srv, int32_t speed,
 
     // Don't allow new user command if update loop not registered.
     if (!pbio_servo_update_loop_is_running(srv)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Stop parent object that uses this motor, if any.
@@ -691,7 +691,7 @@ pbio_error_t pbio_servo_run_target(pbio_servo_t *srv, int32_t speed, int32_t tar
 
     // Don't allow new user command if update loop not registered.
     if (!pbio_servo_update_loop_is_running(srv)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Stop parent object that uses this motor, if any.
@@ -741,7 +741,7 @@ pbio_error_t pbio_servo_run_angle(pbio_servo_t *srv, int32_t speed, int32_t angl
 
     // Don't allow new user command if update loop not registered.
     if (!pbio_servo_update_loop_is_running(srv)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Stop parent object that uses this motor, if any.
@@ -786,7 +786,7 @@ pbio_error_t pbio_servo_track_target(pbio_servo_t *srv, int32_t target) {
 
     // Don't allow new user command if update loop not registered.
     if (!pbio_servo_update_loop_is_running(srv)) {
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Stop parent object that uses this motor, if any.
@@ -816,7 +816,7 @@ pbio_error_t pbio_servo_is_stalled(pbio_servo_t *srv, bool *stalled, uint32_t *s
     if (!pbio_servo_update_loop_is_running(srv)) {
         *stalled = false;
         *stall_duration = 0;
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // If control is active, this provides the most accurate stall detection.
@@ -856,7 +856,7 @@ pbio_error_t pbio_servo_get_load(pbio_servo_t *srv, int32_t *load) {
     // Don't allow access if update loop not registered.
     if (!pbio_servo_update_loop_is_running(srv)) {
         *load = 0;
-        return PBIO_ERROR_INVALID_OP;
+        return PBIO_ERROR_NO_DEV;
     }
 
     // Get passive actuation type.

lib/pbio/test/src/test_drivebase.c

@@ -161,7 +161,7 @@ static pbio_error_t test_drivebase_basics(pbio_os_state_t *state, void *context)
     // Closing any motor should make drivebase operations invalid.
     tt_uint_op(pbio_dcmotor_close(srv_left->dcmotor), ==, PBIO_SUCCESS);
     PBIO_OS_AWAIT_MS(state, &timer, 100);
-    tt_uint_op(pbio_drivebase_is_stalled(db, &stalled, &stall_duration), ==, PBIO_ERROR_INVALID_OP);
+    tt_uint_op(pbio_drivebase_is_stalled(db, &stalled, &stall_duration), ==, PBIO_ERROR_NO_DEV);
 
 end: