1 files changed, 21 insertions, 8 deletions

diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index 5824b20b5fcb..3db7767d2a17 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -29,8 +29,6 @@ enum can_mode {
 /*
  * CAN common private data
  */
-#define CAN_ECHO_SKB_MAX  4
-
 struct can_priv {
         struct can_device_stats can_stats;
 
@@ -44,15 +42,25 @@ struct can_priv {
         int restart_ms;
         struct timer_list restart_timer;
 
-        struct sk_buff *echo_skb[CAN_ECHO_SKB_MAX];
-
         int (*do_set_bittiming)(struct net_device *dev);
         int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
         int (*do_get_state)(const struct net_device *dev,
                             enum can_state *state);
+
+        unsigned int echo_skb_max;
+        struct sk_buff **echo_skb;
 };
 
-struct net_device *alloc_candev(int sizeof_priv);
+/*
+ * get_can_dlc(value) - helper macro to cast a given data length code (dlc)
+ * to __u8 and ensure the dlc value to be max. 8 bytes.
+ *
+ * To be used in the CAN netdriver receive path to ensure conformance with
+ * ISO 11898-1 Chapter 8.4.2.3 (DLC field)
+ */
+#define get_can_dlc(i)  (min_t(__u8, (i), 8))
+
+struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
 void free_candev(struct net_device *dev);
 
 int open_candev(struct net_device *dev);
@@ -64,8 +72,13 @@ void unregister_candev(struct net_device *dev);
 int can_restart_now(struct net_device *dev);
 void can_bus_off(struct net_device *dev);
 
-void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, int idx);
-void can_get_echo_skb(struct net_device *dev, int idx);
-void can_free_echo_skb(struct net_device *dev, int idx);
+void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
+                      unsigned int idx);
+void can_get_echo_skb(struct net_device *dev, unsigned int idx);
+void can_free_echo_skb(struct net_device *dev, unsigned int idx);
+
+struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
+struct sk_buff *alloc_can_err_skb(struct net_device *dev,
+                                  struct can_frame **cf);
 
 #endif /* CAN_DEV_H */