CAN: Use mp_obj_t insteaed of canio_message_obj_t, get rid of rtr field

Author: jepler

ports/atmel-samd/common-hal/canio/CAN.c

@@ -328,16 +328,18 @@ static void maybe_auto_restart(canio_can_obj_t *self) {
     }
 }
 
-void common_hal_canio_can_send(canio_can_obj_t *self, canio_message_obj_t *message)
+void common_hal_canio_can_send(canio_can_obj_t *self, mp_obj_t message_in)
 {
     maybe_auto_restart(self);
 
+    canio_message_obj_t *message = message_in;;
     // We have just one dedicated TX buffer, use it!
     canio_can_tx_buffer_t *ent = &self->state->tx_buffer[0];
 
+    bool rtr = message->base.type == &canio_remote_transmission_request_type;
     ent->txb0.bit.ESI = false;
     ent->txb0.bit.XTD = message->extended;
-    ent->txb0.bit.RTR = message->rtr;
+    ent->txb0.bit.RTR = rtr;
     if (message->extended) {
         ent->txb0.bit.ID = message->id;
     } else {
@@ -350,7 +352,7 @@ void common_hal_canio_can_send(canio_can_obj_t *self, canio_message_obj_t *messa
     ent->txb1.bit.BRS = 0; // No bit rate switching
     ent->txb1.bit.DLC = message->size;
 
-    if (!message->rtr) {
+    if (!rtr) {
         memcpy(ent->data, message->data, message->size);
     }
 

ports/atmel-samd/common-hal/canio/Listener.c

@@ -349,30 +349,32 @@ int common_hal_canio_listener_in_waiting(canio_listener_obj_t *self) {
     return self->hw->RXFS.bit.F0FL;
 }
 
-bool common_hal_canio_listener_receiveinto(canio_listener_obj_t *self, canio_message_obj_t *message) {
+mp_obj_t common_hal_canio_listener_receive(canio_listener_obj_t *self) {
     if (!common_hal_canio_listener_in_waiting(self)) {
         uint64_t deadline = supervisor_ticks_ms64() + self->timeout_ms;
         do {
             if (supervisor_ticks_ms64() > deadline) {
-                return false;
+                return NULL;
             }
         } while (!common_hal_canio_listener_in_waiting(self));
     }
     int index = self->hw->RXFS.bit.F0GI;
     canio_can_rx_fifo_t *hw_message = &self->fifo[index];
+    bool rtr = hw_message->rxf0.bit.RTR;
+    canio_message_obj_t *message = m_new_obj(canio_message_obj_t);
+    message->base.type = rtr ? &canio_remote_transmission_request_type : &canio_message_type;
     message->extended = hw_message->rxf0.bit.XTD;
     if (message->extended) {
         message->id = hw_message->rxf0.bit.ID;
     } else {
         message->id = hw_message->rxf0.bit.ID >> 18; // short ids are left-justified
     }
-    message->rtr = hw_message->rxf0.bit.RTR;
     message->size = hw_message->rxf1.bit.DLC;
-    if (!message->rtr) {
+    if (!rtr) {
         memcpy(message->data, hw_message->data, message->size);
     }
     self->hw->RXFA.bit.F0AI = index;
-    return true;
+    return message;
 }
 
 void common_hal_canio_listener_deinit(canio_listener_obj_t *self) {

shared-bindings/canio/CAN.h

@@ -51,5 +51,5 @@ void common_hal_canio_can_auto_restart_set(canio_can_obj_t *self, bool auto_rest
 void common_hal_canio_can_check_for_deinit(canio_can_obj_t *self);
 void common_hal_canio_can_deinit(canio_can_obj_t *self);
 void common_hal_canio_can_restart(canio_can_obj_t *self);
-void common_hal_canio_can_send(canio_can_obj_t *self, canio_message_obj_t *message);
+void common_hal_canio_can_send(canio_can_obj_t *self, mp_obj_t message);
 void common_hal_canio_reset(void);

shared-bindings/canio/Listener.c

@@ -49,17 +49,11 @@ STATIC mp_obj_t canio_listener_receive(mp_obj_t self_in) {
     canio_listener_obj_t *self = MP_OBJ_TO_PTR(self_in);
     common_hal_canio_listener_check_for_deinit(self);
 
-    canio_message_obj_t *message = m_new_obj(canio_message_obj_t);
-
-    if (common_hal_canio_listener_receiveinto(self, message)) {
-        if (message->rtr) {
-            message->base.type = &canio_remote_transmission_request_type;
-        } else {
-            message->base.type = &canio_message_type;
-        }
+    mp_obj_t message = common_hal_canio_listener_receive(self);
+    // note: receive fills out the type field of the message
+
+    if (message) {
         return message;
-    } else {
-        m_free(message); // message did not escape into vm
     }
     return mp_const_none;
 }

shared-bindings/canio/Listener.h

@@ -37,7 +37,7 @@ typedef struct canio_listener_obj canio_listener_obj_t;
 void common_hal_canio_listener_construct(canio_listener_obj_t *self, canio_can_obj_t *can, size_t nmatch, canio_match_obj_t **matches, float timeout);
 void common_hal_canio_listener_check_for_deinit(canio_listener_obj_t *self);
 void common_hal_canio_listener_deinit(canio_listener_obj_t *self);
-bool common_hal_canio_listener_receiveinto(canio_listener_obj_t *self, canio_message_obj_t *message);
+mp_obj_t common_hal_canio_listener_receive(canio_listener_obj_t *self);
 int common_hal_canio_listener_in_waiting(canio_listener_obj_t *self);
 float common_hal_canio_listener_get_timeout(canio_listener_obj_t *self);
 void common_hal_canio_listener_set_timeout(canio_listener_obj_t *self, float timeout);

shared-module/canio/Message.c

@@ -32,7 +32,6 @@ void common_hal_canio_message_construct(canio_message_obj_t *self, int id, void
 {
     self->id = id;
     self->size = size;
-    self->rtr = !data;
     self->extended = extended;
     if (data) {
         memcpy(self->data, data, size);
@@ -57,7 +56,6 @@ const void *common_hal_canio_message_get_data(const canio_message_obj_t *self)
 
 const void common_hal_canio_message_set_data(canio_message_obj_t *self, const void *data, size_t size)
 {
-    self->rtr = false;
     self->size = size;
     memcpy(self->data, data, size);
 }

shared-module/canio/Message.h

@@ -33,6 +33,5 @@ typedef struct {
     int id;
     uint8_t data[8];
     size_t size:4;
-    bool rtr:1;
     bool extended:1;
 } canio_message_obj_t;

shared-module/canio/RemoteTransmissionRequest.c

@@ -33,7 +33,6 @@ void common_hal_canio_remote_transmission_request_construct(canio_remote_transmi
 {
     self->id = id;
     self->size = size;
-    self->rtr = true;
     self->extended = extended;
 }