Merge branch 'master' of git://gitorious.org/linux-can/linux-can-next

Marc Kleine-Budde says:

====================
here is our second pull request for net-next. In this series Federico
Vaga adds a pci driver for c_can/d_can hardware using the existing
generic c_can driver. The remaining 6 patches are by Oliver Hartkopp.
He adds CANFD support to the CAN stack while keeping binary
compatibility for existing applications. CANFD is an extension to the
existing CAN standard, it allows longer CAN frames and/or higher data
rates. There's no real hardware available yet, but this series adds
CANFD support to the vcan driver.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 85 insertions, 17 deletions

diff --git a/include/linux/can.h b/include/linux/can.h
index 17334c09bd93..1a66cf6112ae 100644
--- a/include/linux/can.h
+++ b/include/linux/can.h
@@ -46,18 +46,67 @@ typedef __u32 canid_t;
  */
 typedef __u32 can_err_mask_t;
 
+/* CAN payload length and DLC definitions according to ISO 11898-1 */
+#define CAN_MAX_DLC 8
+#define CAN_MAX_DLEN 8
+
+/* CAN FD payload length and DLC definitions according to ISO 11898-7 */
+#define CANFD_MAX_DLC 15
+#define CANFD_MAX_DLEN 64
+
 /**
  * struct can_frame - basic CAN frame structure
- * @can_id:  the CAN ID of the frame and CAN_*_FLAG flags, see above.
- * @can_dlc: the data length field of the CAN frame
- * @data:    the CAN frame payload.
+ * @can_id:  CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition
+ * @can_dlc: frame payload length in byte (0 .. 8) aka data length code
+ *           N.B. the DLC field from ISO 11898-1 Chapter 8.4.2.3 has a 1:1
+ *           mapping of the 'data length code' to the real payload length
+ * @data:    CAN frame payload (up to 8 byte)
  */
 struct can_frame {
 	canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
-	__u8    can_dlc; /* data length code: 0 .. 8 */
-	__u8    data[8] __attribute__((aligned(8)));
+	__u8    can_dlc; /* frame payload length in byte (0 .. CAN_MAX_DLEN) */
+	__u8    data[CAN_MAX_DLEN] __attribute__((aligned(8)));
 };
 
+/*
+ * defined bits for canfd_frame.flags
+ *
+ * As the default for CAN FD should be to support the high data rate in the
+ * payload section of the frame (HDR) and to support up to 64 byte in the
+ * data section (EDL) the bits are only set in the non-default case.
+ * Btw. as long as there's no real implementation for CAN FD network driver
+ * these bits are only preliminary.
+ *
+ * RX: NOHDR/NOEDL - info about received CAN FD frame
+ *     ESI         - bit from originating CAN controller
+ * TX: NOHDR/NOEDL - control per-frame settings if supported by CAN controller
+ *     ESI         - bit is set by local CAN controller
+ */
+#define CANFD_NOHDR 0x01 /* frame without high data rate */
+#define CANFD_NOEDL 0x02 /* frame without extended data length */
+#define CANFD_ESI   0x04 /* error state indicator */
+
+/**
+ * struct canfd_frame - CAN flexible data rate frame structure
+ * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition
+ * @len:    frame payload length in byte (0 .. CANFD_MAX_DLEN)
+ * @flags:  additional flags for CAN FD
+ * @__res0: reserved / padding
+ * @__res1: reserved / padding
+ * @data:   CAN FD frame payload (up to CANFD_MAX_DLEN byte)
+ */
+struct canfd_frame {
+	canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
+	__u8    len;     /* frame payload length in byte */
+	__u8    flags;   /* additional flags for CAN FD */
+	__u8    __res0;  /* reserved / padding */
+	__u8    __res1;  /* reserved / padding */
+	__u8    data[CANFD_MAX_DLEN] __attribute__((aligned(8)));
+};
+
+#define CAN_MTU		(sizeof(struct can_frame))
+#define CANFD_MTU	(sizeof(struct canfd_frame))
+
 /* particular protocols of the protocol family PF_CAN */
 #define CAN_RAW		1 /* RAW sockets */
 #define CAN_BCM		2 /* Broadcast Manager */
diff --git a/include/linux/can/core.h b/include/linux/can/core.h
index 0ccc1cd28b95..78c6c52073ad 100644
--- a/include/linux/can/core.h
+++ b/include/linux/can/core.h
@@ -17,10 +17,10 @@
 #include <linux/skbuff.h>
 #include <linux/netdevice.h>
 
-#define CAN_VERSION "20090105"
+#define CAN_VERSION "20120528"
 
 /* increment this number each time you change some user-space interface */
-#define CAN_ABI_VERSION "8"
+#define CAN_ABI_VERSION "9"
 
 #define CAN_VERSION_STRING "rev " CAN_VERSION " abi " CAN_ABI_VERSION
 
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index 5d2efe7e3f1b..ee5a771fb20d 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -61,23 +61,40 @@ struct can_priv {
  * 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))
+#define get_can_dlc(i)		(min_t(__u8, (i), CAN_MAX_DLC))
+#define get_canfd_dlc(i)	(min_t(__u8, (i), CANFD_MAX_DLC))
 
 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */
 static inline int can_dropped_invalid_skb(struct net_device *dev,
 					  struct sk_buff *skb)
 {
-	const struct can_frame *cf = (struct can_frame *)skb->data;
-
-	if (unlikely(skb->len != sizeof(*cf) || cf->can_dlc > 8)) {
-		kfree_skb(skb);
-		dev->stats.tx_dropped++;
-		return 1;
-	}
+	const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
+	if (skb->protocol == htons(ETH_P_CAN)) {
+		if (unlikely(skb->len != CAN_MTU ||
+			     cfd->len > CAN_MAX_DLEN))
+			goto inval_skb;
+	} else if (skb->protocol == htons(ETH_P_CANFD)) {
+		if (unlikely(skb->len != CANFD_MTU ||
+			     cfd->len > CANFD_MAX_DLEN))
+			goto inval_skb;
+	} else
+		goto inval_skb;
 
 	return 0;
+
+inval_skb:
+	kfree_skb(skb);
+	dev->stats.tx_dropped++;
+	return 1;
 }
 
+/* get data length from can_dlc with sanitized can_dlc */
+u8 can_dlc2len(u8 can_dlc);
+
+/* map the sanitized data length to an appropriate data length code */
+u8 can_len2dlc(u8 len);
+
 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
 void free_candev(struct net_device *dev);
 
diff --git a/include/linux/can/raw.h b/include/linux/can/raw.h
index 781f3a3701be..a814062b0719 100644
--- a/include/linux/can/raw.h
+++ b/include/linux/can/raw.h
@@ -23,7 +23,8 @@ enum {
 	CAN_RAW_FILTER = 1,	/* set 0 .. n can_filter(s)          */
 	CAN_RAW_ERR_FILTER,	/* set filter for error frames       */
 	CAN_RAW_LOOPBACK,	/* local loopback (default:on)       */
-	CAN_RAW_RECV_OWN_MSGS	/* receive my own msgs (default:off) */
+	CAN_RAW_RECV_OWN_MSGS,	/* receive my own msgs (default:off) */
+	CAN_RAW_FD_FRAMES,	/* allow CAN FD frames (default:off) */
 };
 
 #endif
diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h
index 56d907a2c804..167ce5b363d2 100644
--- a/include/linux/if_ether.h
+++ b/include/linux/if_ether.h
@@ -105,7 +105,8 @@
 #define ETH_P_WAN_PPP   0x0007          /* Dummy type for WAN PPP frames*/
 #define ETH_P_PPP_MP    0x0008          /* Dummy type for PPP MP frames */
 #define ETH_P_LOCALTALK 0x0009		/* Localtalk pseudo type 	*/
-#define ETH_P_CAN	0x000C		/* Controller Area Network      */
+#define ETH_P_CAN	0x000C		/* CAN: Controller Area Network */
+#define ETH_P_CANFD	0x000D		/* CANFD: CAN flexible data rate*/
 #define ETH_P_PPPTALK	0x0010		/* Dummy type for Atalk over PPP*/
 #define ETH_P_TR_802_2	0x0011		/* 802.2 frames 		*/
 #define ETH_P_MOBITEX	0x0015		/* Mobitex (kaz@cafe.net)	*/