Consolidate and unify state change handling

---
 drivers/net/can/mscan/mscan.c | 62 
+++++++++++++++++++------------------------
 1 file changed, 28 insertions(+), 34 deletions(-)

index e0c9be5..c7b5b33 100644
@@ -289,18 +289,15 @@ static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev)
     return NETDEV_TX_OK;
 }
 
-/* This function returns the old state to see where we came from */
-static enum can_state check_set_state(struct net_device *dev, u8 canrflg)
+static enum can_state get_new_state(struct net_device *dev, u8 canrflg)
 {
     struct mscan_priv *priv = netdev_priv(dev);
-    enum can_state state, old_state = priv->can.state;
 
-    if (canrflg & MSCAN_CSCIF && old_state <= CAN_STATE_BUS_OFF) {
-        state = state_map[max(MSCAN_STATE_RX(canrflg),
-                      MSCAN_STATE_TX(canrflg))];
-        priv->can.state = state;
-    }
-    return old_state;
+    if (unlikely(canrflg & MSCAN_CSCIF))
+        return state_map[max(MSCAN_STATE_RX(canrflg),
+                 MSCAN_STATE_TX(canrflg))];
+
+    return priv->can.state;
 }
 
 static void mscan_get_rx_frame(struct net_device *dev, struct 

can_frame *frame)
@@ -343,13 +340,28 @@ static void mscan_get_rx_frame(struct net_device *dev, struct can_frame *frame)

     out_8(&regs->canrflg, MSCAN_RXF);

}

+static unsigned int mscan_get_err_dir(struct mscan_priv *priv, u8 canrflg) +{
+ enum can_err_dir dir = CAN_ERR_DIR_UNKNOWN;
+
+ if ((priv->shadow_statflg & MSCAN_RSTAT_MSK) <
+ (canrflg & MSCAN_RSTAT_MSK))
+ dir |= CAN_ERR_DIR_RX;
+
+ if ((priv->shadow_statflg & MSCAN_TSTAT_MSK) <
+ (canrflg & MSCAN_TSTAT_MSK))
+ dir |= CAN_ERR_DIR_TX;
+
+ return dir;
+}
+
static void mscan_get_err_frame(struct net_device *dev, struct
can_frame *frame,
u8 canrflg)

 {
     struct mscan_priv *priv = netdev_priv(dev);
     struct mscan_regs __iomem *regs = priv->reg_base;
     struct net_device_stats *stats = &dev->stats;

- enum can_state old_state;
+ enum can_state state;

     netdev_dbg(dev, "error interrupt (canrflg=%#x)\n", canrflg);
     frame->can_id = CAN_ERR_FLAG;
@@ -363,27 +375,12 @@ static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame,
         frame->data[1] = 0;
     }

-    old_state = check_set_state(dev, canrflg);
-    /* State changed */
-    if (old_state != priv->can.state) {
-        switch (priv->can.state) {
-        case CAN_STATE_ERROR_WARNING:
-            frame->can_id |= CAN_ERR_CRTL;
-            priv->can.can_stats.error_warning++;
-            if ((priv->shadow_statflg & MSCAN_RSTAT_MSK) <

- (canrflg & MSCAN_RSTAT_MSK))
- frame->data[1] |= CAN_ERR_CRTL_RX_WARNING;
- if ((priv->shadow_statflg & MSCAN_TSTAT_MSK) <
- (canrflg & MSCAN_TSTAT_MSK))
- frame->data[1] |= CAN_ERR_CRTL_TX_WARNING;
- break;
- case CAN_STATE_ERROR_PASSIVE:

-            frame->can_id |= CAN_ERR_CRTL;
-            priv->can.can_stats.error_passive++;
-            frame->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
-            break;

- case CAN_STATE_BUS_OFF:
- frame->can_id |= CAN_ERR_BUSOFF;
+ state = get_new_state(dev, canrflg);
+ if (state != priv->can.state) {
+ can_change_state(dev, frame, state,
+ mscan_get_err_dir(priv, canrflg));
+
+ if (priv->can.state == CAN_STATE_BUS_OFF) {
/*
* The MSCAN on the MPC5200 does recover from bus-off
* automatically. To avoid that we stop the chip doing
@@ -396,9 +393,6 @@ static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame,

                      MSCAN_SLPRQ | MSCAN_INITRQ);
             }
             can_bus_off(dev);
-            break;
-        default:
-            break;
         }
     }
     priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;