can-dev: implement len8_dlc in some CAN USB adapters for testing

Namely those that are in mainline and I currently have on my desk ...

Signed-off-by Oliver Hartkopp <[email protected]>

---
  drivers/net/can/usb/gs_usb.c               |  8 ++++++--
  drivers/net/can/usb/peak_usb/pcan_usb.c    |  8 ++++++--
  drivers/net/can/usb/peak_usb/pcan_usb_fd.c | 16 +++++++++++-----
  drivers/net/can/usb/usb_8dev.c             | 10 ++++++----
  include/linux/can/dev.h                    | 15 +++++++++++++++
  5 files changed, 44 insertions(+), 13 deletions(-)

drivers/net/can/usb/gs_usb.c +6 -2

index 3a097c240e5a..fab6ed073e45 100644
@@ -330,10 +330,13 @@ static void gs_usb_receive_bulk_callback(struct urb *urb)
  			return;
 
  		cf->can_id = hf->can_id;
 
  		cf->len = can_get_cc_len(hf->len);
+		cf->len8_dlc = can_get_len8_dlc(dev->can.ctrlmode, cf->len,
+						hf->len);
+
  		memcpy(cf->data, hf->data, 8);
 
  		/* ERROR frames tell us information about the controller */
  		if (hf->can_id & CAN_ERR_FLAG)
  			gs_update_state(dev, cf);

@@ -502,11 +505,12 @@ static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb,
  	hf->channel = dev->channel;
 
  	cf = (struct can_frame *)skb->data;
 
  	hf->can_id = cf->can_id;
-	hf->len = cf->len;
+	hf->len = can_get_cc_dlc(dev->can.ctrlmode, cf->len, cf->len8_dlc);
+
  	memcpy(hf->data, cf->data, cf->len);
 
  	usb_fill_bulk_urb(urb, dev->udev,
  			  usb_sndbulkpipe(dev->udev, GSUSB_ENDPOINT_OUT),
  			  hf,

@@ -856,11 +860,11 @@ static struct gs_can *gs_make_candev(unsigned int channel,
  	dev->can.state = CAN_STATE_STOPPED;
  	dev->can.clock.freq = bt_const->fclk_can;
  	dev->can.bittiming_const = &dev->bt_const;
  	dev->can.do_set_bittiming = gs_usb_set_bittiming;
 
-	dev->can.ctrlmode_supported = 0;
+	dev->can.ctrlmode_supported = CAN_CTRLMODE_CC_LEN8_DLC;
 
  	if (bt_const->feature & GS_CAN_FEATURE_LISTEN_ONLY)
  		dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY;
 
  	if (bt_const->feature & GS_CAN_FEATURE_LOOP_BACK)

drivers/net/can/usb/peak_usb/pcan_usb.c +6 -2

index abecb77e34f2..105a17dc8075 100644
@@ -733,10 +733,12 @@ static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len)
 
  		cf->can_id = le16_to_cpu(tmp16) >> 5;
  	}
 
  	cf->len = can_get_cc_len(rec_len);
+	cf->len8_dlc = can_get_len8_dlc(mc->pdev->dev.can.ctrlmode, cf->len,
+					rec_len);
 
  	/* Only first packet timestamp is a word */
  	if (pcan_usb_decode_ts(mc, !mc->rec_ts_idx))
  		goto decode_failed;
 

@@ -836,11 +838,12 @@ static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb,
  	obuf[1] = 1;
 
  	pc = obuf + PCAN_USB_MSG_HEADER_LEN;
 
  	/* status/len byte */
-	*pc = cf->len;
+	*pc = can_get_cc_dlc(dev->can.ctrlmode, cf->len, cf->len8_dlc);
+
  	if (cf->can_id & CAN_RTR_FLAG)
  		*pc |= PCAN_USB_STATUSLEN_RTR;
 
  	/* can id */
  	if (cf->can_id & CAN_EFF_FLAG) {

@@ -990,11 +993,12 @@ static const struct can_bittiming_const pcan_usb_const = {
  const struct peak_usb_adapter pcan_usb = {
  	.name = "PCAN-USB",
  	.device_id = PCAN_USB_PRODUCT_ID,
  	.ctrl_count = 1,
  	.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY |
-			      CAN_CTRLMODE_BERR_REPORTING,
+			      CAN_CTRLMODE_BERR_REPORTING |
+			      CAN_CTRLMODE_CC_LEN8_DLC,
  	.clock = {
  		.freq = PCAN_USB_CRYSTAL_HZ / 2 ,
  	},
  	.bittiming_const = &pcan_usb_const,
 

drivers/net/can/usb/peak_usb/pcan_usb_fd.c +11 -5

index 3e875cdbadac..3ed30ab79784 100644
@@ -492,16 +492,20 @@ static int pcan_usb_fd_decode_canmsg(struct pcan_usb_fd_if *usb_if,
  		if (rx_msg_flags & PUCAN_MSG_ERROR_STATE_IND)
  			cfd->flags |= CANFD_ESI;
 
  		cfd->len = can_dlc2len(pucan_msg_get_dlc(rm));
  	} else {
+		struct can_frame *cf = (struct can_frame *)cfd;
+
  		/* CAN 2.0 frame case */
  		skb = alloc_can_skb(netdev, (struct can_frame **)&cfd);
  		if (!skb)
  			return -ENOMEM;
 
  		cfd->len = can_get_cc_len(pucan_msg_get_dlc(rm));
+		cf->len8_dlc = can_get_len8_dlc(dev->can.ctrlmode, cf->len,
+						pucan_msg_get_dlc(rm));
  	}
 
  	cfd->can_id = le32_to_cpu(rm->can_id);
 
  	if (rx_msg_flags & PUCAN_MSG_EXT_ID)

@@ -764,12 +768,14 @@ static int pcan_usb_fd_encode_msg(struct peak_usb_device *dev,
  			tx_msg_flags |= PUCAN_MSG_BITRATE_SWITCH;
 
  		if (cfd->flags & CANFD_ESI)
  			tx_msg_flags |= PUCAN_MSG_ERROR_STATE_IND;
  	} else {
+		struct can_frame *cf = (struct can_frame *)cfd;
+
  		/* CAND 2.0 frames */
-		len = cfd->len;
+		len = can_get_cc_dlc(dev->can.ctrlmode, cf->len, cf->len8_dlc);
 
  		if (cfd->can_id & CAN_RTR_FLAG)
  			tx_msg_flags |= PUCAN_MSG_RTR;
  	}
 

@@ -1033,11 +1039,11 @@ static const struct can_bittiming_const pcan_usb_fd_data_const = {
 
  const struct peak_usb_adapter pcan_usb_fd = {
  	.name = "PCAN-USB FD",
  	.device_id = PCAN_USBFD_PRODUCT_ID,
  	.ctrl_count = PCAN_USBFD_CHANNEL_COUNT,
-	.ctrlmode_supported = CAN_CTRLMODE_FD |
+	.ctrlmode_supported = CAN_CTRLMODE_FD | CAN_CTRLMODE_CC_LEN8_DLC |
  			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
  	.clock = {
  		.freq = PCAN_UFD_CRYSTAL_HZ,
  	},
  	.bittiming_const = &pcan_usb_fd_const,

@@ -1105,11 +1111,11 @@ static const struct can_bittiming_const pcan_usb_chip_data_const = {
 
  const struct peak_usb_adapter pcan_usb_chip = {
  	.name = "PCAN-Chip USB",
  	.device_id = PCAN_USBCHIP_PRODUCT_ID,
  	.ctrl_count = PCAN_USBFD_CHANNEL_COUNT,
-	.ctrlmode_supported = CAN_CTRLMODE_FD |
+	.ctrlmode_supported = CAN_CTRLMODE_FD | CAN_CTRLMODE_CC_LEN8_DLC |
  		CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
  	.clock = {
  		.freq = PCAN_UFD_CRYSTAL_HZ,
  	},
  	.bittiming_const = &pcan_usb_chip_const,

@@ -1177,11 +1183,11 @@ static const struct can_bittiming_const pcan_usb_pro_fd_data_const = {
 
  const struct peak_usb_adapter pcan_usb_pro_fd = {
  	.name = "PCAN-USB Pro FD",
  	.device_id = PCAN_USBPROFD_PRODUCT_ID,
  	.ctrl_count = PCAN_USBPROFD_CHANNEL_COUNT,
-	.ctrlmode_supported = CAN_CTRLMODE_FD |
+	.ctrlmode_supported = CAN_CTRLMODE_FD | CAN_CTRLMODE_CC_LEN8_DLC |
  			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
  	.clock = {
  		.freq = PCAN_UFD_CRYSTAL_HZ,
  	},
  	.bittiming_const = &pcan_usb_pro_fd_const,

@@ -1249,11 +1255,11 @@ static const struct can_bittiming_const pcan_usb_x6_data_const = {
 
  const struct peak_usb_adapter pcan_usb_x6 = {
  	.name = "PCAN-USB X6",
  	.device_id = PCAN_USBX6_PRODUCT_ID,
  	.ctrl_count = PCAN_USBPROFD_CHANNEL_COUNT,
-	.ctrlmode_supported = CAN_CTRLMODE_FD |
+	.ctrlmode_supported = CAN_CTRLMODE_FD | CAN_CTRLMODE_CC_LEN8_DLC |
  			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
  	.clock = {
  		.freq = PCAN_UFD_CRYSTAL_HZ,
  	},
  	.bittiming_const = &pcan_usb_x6_const,

drivers/net/can/usb/usb_8dev.c +6 -4

index 8aedb2ba37fb..940f1720297e 100644
@@ -469,11 +469,12 @@ static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv,
  		if (!skb)
  			return;
 
  		cf->can_id = be32_to_cpu(msg->id);
  		cf->len = can_get_cc_len(msg->dlc & 0xF);
-
+		cf->len8_dlc = can_get_len8_dlc(priv->can.ctrlmode, cf->len,
+						msg->dlc & 0xF);
  		if (msg->flags & USB_8DEV_EXTID)
  			cf->can_id |= CAN_EFF_FLAG;
 
  		if (msg->flags & USB_8DEV_RTR)
  			cf->can_id |= CAN_RTR_FLAG;

@@ -635,11 +636,11 @@ static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
 
  	if (cf->can_id & CAN_EFF_FLAG)
  		msg->flags |= USB_8DEV_EXTID;
 
  	msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK);
-	msg->dlc = cf->len;
+	msg->dlc = can_get_cc_dlc(priv->can.ctrlmode, cf->len, cf->len8_dlc);
  	memcpy(msg->data, cf->data, cf->len);
  	msg->end = USB_8DEV_DATA_END;
 
  	for (i = 0; i < MAX_TX_URBS; i++) {
  		if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {

@@ -925,12 +926,13 @@ static int usb_8dev_probe(struct usb_interface *intf,
  	priv->can.clock.freq = USB_8DEV_ABP_CLOCK;
  	priv->can.bittiming_const = &usb_8dev_bittiming_const;
  	priv->can.do_set_mode = usb_8dev_set_mode;
  	priv->can.do_get_berr_counter = usb_8dev_get_berr_counter;
  	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
-				      CAN_CTRLMODE_LISTENONLY |
-				      CAN_CTRLMODE_ONE_SHOT;
+				       CAN_CTRLMODE_LISTENONLY |
+				       CAN_CTRLMODE_ONE_SHOT |
+				       CAN_CTRLMODE_CC_LEN8_DLC;
 
  	netdev->netdev_ops = &usb_8dev_netdev_ops;
 
  	netdev->flags |= IFF_ECHO; /* we support local echo */
 

include/linux/can/dev.h +15 -0

index 45018fbad35f..dd7cc705c81a 100644
@@ -168,10 +168,25 @@ static inline bool can_is_canfd_skb(const struct sk_buff *skb)
  {
  	/* the CAN specific type of skb is identified by its data length */
  	return skb->len == CANFD_MTU;
  }
 
+static inline u8 can_check_len8_dlc(u32 ctrlmode, u8 len, u8 dlc, u8 ret)
+{
+	/* return value for len8_dlc only if all conditions apply */
+	if ((ctrlmode & CAN_CTRLMODE_CC_LEN8_DLC) &&
+	    (len == CAN_MAX_DLEN) &&
+	    (dlc > CAN_MAX_DLEN && dlc <= CAN_MAX_RAW_DLC))
+		ret = dlc;
+
+	/* no valid len8_dlc value -> return provided default value */
+	return ret;
+}
+
+#define can_get_len8_dlc(cm, len, dlc) can_check_len8_dlc(cm, len, dlc, 0)
+#define can_get_cc_dlc(cm, len, dlc) can_check_len8_dlc(cm, len, dlc, len)
+
  /* helper to define static CAN controller features at device creation time */
  static inline void can_set_static_ctrlmode(struct net_device *dev,
  					   u32 static_mode)
  {
  	struct can_priv *priv = netdev_priv(dev);

Info: usb8dev and gs_usb work as expected.

The hack for the PCAN FD adapter crashes the system - I have to look into it ...

Quoted 1 line · Oliver Hartkopp

Info: usb8dev and gs_usb work as expected.

Which gs_usb are you using? The original one, or the candelight?