can: drivers: add len8_dlc support for various CAN adapters

Support the Classical CAN raw DLC functionality to send and receive DLC values
from 9 .. 15 on various Classical CAN capable CAN network drivers:

- sja1000
- gs_usb
- pcan_usb
- pcan_usb_fd
- usb_8dev
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201111095923.2535-1-socketcan@hartkopp.net
[mkl: usb_8dev: changed indention]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/sja1000/sja1000.c

@@ -284,7 +284,6 @@ static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
 	struct sja1000_priv *priv = netdev_priv(dev);
 	struct can_frame *cf = (struct can_frame *)skb->data;
 	uint8_t fi;
-	uint8_t dlc;
 	canid_t id;
 	uint8_t dreg;
 	u8 cmd_reg_val = 0x00;
@@ -295,7 +294,7 @@ static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
 
 	netif_stop_queue(dev);
 
-	fi = dlc = cf->len;
+	fi = can_get_cc_dlc(cf, priv->can.ctrlmode);
 	id = cf->can_id;
 
 	if (id & CAN_RTR_FLAG)
@@ -316,7 +315,7 @@ static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb,
 		priv->write_reg(priv, SJA1000_ID2, (id & 0x00000007) << 5);
 	}
 
-	for (i = 0; i < dlc; i++)
+	for (i = 0; i < cf->len; i++)
 		priv->write_reg(priv, dreg++, cf->data[i]);
 
 	can_put_echo_skb(skb, dev, 0);
@@ -367,7 +366,7 @@ static void sja1000_rx(struct net_device *dev)
 		    | (priv->read_reg(priv, SJA1000_ID2) >> 5);
 	}
 
-	cf->len = can_cc_dlc2len(fi & 0x0F);
+	can_frame_set_cc_len(cf, fi & 0x0F, priv->can.ctrlmode);
 	if (fi & SJA1000_FI_RTR) {
 		id |= CAN_RTR_FLAG;
 	} else {
@@ -638,7 +637,8 @@ struct net_device *alloc_sja1000dev(int sizeof_priv)
 				       CAN_CTRLMODE_3_SAMPLES |
 				       CAN_CTRLMODE_ONE_SHOT |
 				       CAN_CTRLMODE_BERR_REPORTING |
-				       CAN_CTRLMODE_PRESUME_ACK;
+				       CAN_CTRLMODE_PRESUME_ACK |
+				       CAN_CTRLMODE_CC_LEN8_DLC;
 
 	spin_lock_init(&priv->cmdreg_lock);
 

drivers/net/can/usb/gs_usb.c

@@ -331,7 +331,7 @@ static void gs_usb_receive_bulk_callback(struct urb *urb)
 
 		cf->can_id = hf->can_id;
 
-		cf->len = can_cc_dlc2len(hf->can_dlc);
+		can_frame_set_cc_len(cf, hf->can_dlc, dev->can.ctrlmode);
 		memcpy(cf->data, hf->data, 8);
 
 		/* ERROR frames tell us information about the controller */
@@ -504,7 +504,8 @@ static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb,
 	cf = (struct can_frame *)skb->data;
 
 	hf->can_id = cf->can_id;
-	hf->can_dlc = cf->len;
+	hf->can_dlc = can_get_cc_dlc(cf, dev->can.ctrlmode);
+
 	memcpy(hf->data, cf->data, cf->len);
 
 	usb_fill_bulk_urb(urb, dev->udev,
@@ -858,7 +859,7 @@ static struct gs_can *gs_make_candev(unsigned int channel,
 	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;

drivers/net/can/usb/peak_usb/pcan_usb.c

@@ -734,7 +734,7 @@ 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_cc_dlc2len(rec_len);
+	can_frame_set_cc_len(cf, rec_len, mc->pdev->dev.can.ctrlmode);
 
 	/* Only first packet timestamp is a word */
 	if (pcan_usb_decode_ts(mc, !mc->rec_ts_idx))
@@ -838,7 +838,8 @@ static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb,
 	pc = obuf + PCAN_USB_MSG_HEADER_LEN;
 
 	/* status/len byte */
-	*pc = cf->len;
+	*pc = can_get_cc_dlc(cf, dev->can.ctrlmode);
+
 	if (cf->can_id & CAN_RTR_FLAG)
 		*pc |= PCAN_USB_STATUSLEN_RTR;
 
@@ -992,7 +993,8 @@ const struct peak_usb_adapter 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 ,
 	},

drivers/net/can/usb/peak_usb/pcan_usb_fd.c

@@ -499,7 +499,9 @@ static int pcan_usb_fd_decode_canmsg(struct pcan_usb_fd_if *usb_if,
 		if (!skb)
 			return -ENOMEM;
 
-		cfd->len = can_cc_dlc2len(pucan_msg_get_dlc(rm));
+		can_frame_set_cc_len((struct can_frame *)cfd,
+				     pucan_msg_get_dlc(rm),
+				     dev->can.ctrlmode);
 	}
 
 	cfd->can_id = le32_to_cpu(rm->can_id);
@@ -737,7 +739,7 @@ static int pcan_usb_fd_encode_msg(struct peak_usb_device *dev,
 	struct pucan_tx_msg *tx_msg = (struct pucan_tx_msg *)obuf;
 	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
 	u16 tx_msg_size, tx_msg_flags;
-	u8 len;
+	u8 dlc;
 
 	if (cfd->len > CANFD_MAX_DLEN)
 		return -EINVAL;
@@ -756,7 +758,7 @@ static int pcan_usb_fd_encode_msg(struct peak_usb_device *dev,
 
 	if (can_is_canfd_skb(skb)) {
 		/* considering a CANFD frame */
-		len = can_fd_len2dlc(cfd->len);
+		dlc = can_fd_len2dlc(cfd->len);
 
 		tx_msg_flags |= PUCAN_MSG_EXT_DATA_LEN;
 
@@ -767,14 +769,15 @@ static int pcan_usb_fd_encode_msg(struct peak_usb_device *dev,
 			tx_msg_flags |= PUCAN_MSG_ERROR_STATE_IND;
 	} else {
 		/* CAND 2.0 frames */
-		len = cfd->len;
+		dlc = can_get_cc_dlc((struct can_frame *)cfd,
+				     dev->can.ctrlmode);
 
 		if (cfd->can_id & CAN_RTR_FLAG)
 			tx_msg_flags |= PUCAN_MSG_RTR;
 	}
 
 	tx_msg->flags = cpu_to_le16(tx_msg_flags);
-	tx_msg->channel_dlc = PUCAN_MSG_CHANNEL_DLC(dev->ctrl_idx, len);
+	tx_msg->channel_dlc = PUCAN_MSG_CHANNEL_DLC(dev->ctrl_idx, dlc);
 	memcpy(tx_msg->d, cfd->data, cfd->len);
 
 	/* add null size message to tag the end (messages are 32-bits aligned)
@@ -1036,7 +1039,8 @@ const struct peak_usb_adapter pcan_usb_fd = {
 	.device_id = PCAN_USBFD_PRODUCT_ID,
 	.ctrl_count = PCAN_USBFD_CHANNEL_COUNT,
 	.ctrlmode_supported = CAN_CTRLMODE_FD |
-			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
+			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY |
+			CAN_CTRLMODE_CC_LEN8_DLC,
 	.clock = {
 		.freq = PCAN_UFD_CRYSTAL_HZ,
 	},
@@ -1108,7 +1112,8 @@ const struct peak_usb_adapter pcan_usb_chip = {
 	.device_id = PCAN_USBCHIP_PRODUCT_ID,
 	.ctrl_count = PCAN_USBFD_CHANNEL_COUNT,
 	.ctrlmode_supported = CAN_CTRLMODE_FD |
-		CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
+		CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY |
+		CAN_CTRLMODE_CC_LEN8_DLC,
 	.clock = {
 		.freq = PCAN_UFD_CRYSTAL_HZ,
 	},
@@ -1180,7 +1185,8 @@ const struct peak_usb_adapter pcan_usb_pro_fd = {
 	.device_id = PCAN_USBPROFD_PRODUCT_ID,
 	.ctrl_count = PCAN_USBPROFD_CHANNEL_COUNT,
 	.ctrlmode_supported = CAN_CTRLMODE_FD |
-			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
+			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY |
+			CAN_CTRLMODE_CC_LEN8_DLC,
 	.clock = {
 		.freq = PCAN_UFD_CRYSTAL_HZ,
 	},
@@ -1252,7 +1258,8 @@ const struct peak_usb_adapter pcan_usb_x6 = {
 	.device_id = PCAN_USBX6_PRODUCT_ID,
 	.ctrl_count = PCAN_USBPROFD_CHANNEL_COUNT,
 	.ctrlmode_supported = CAN_CTRLMODE_FD |
-			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY,
+			CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY |
+			CAN_CTRLMODE_CC_LEN8_DLC,
 	.clock = {
 		.freq = PCAN_UFD_CRYSTAL_HZ,
 	},

drivers/net/can/usb/usb_8dev.c

@@ -470,7 +470,7 @@ static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv,
 			return;
 
 		cf->can_id = be32_to_cpu(msg->id);
-		cf->len = can_cc_dlc2len(msg->dlc & 0xF);
+		can_frame_set_cc_len(cf, msg->dlc & 0xF, priv->can.ctrlmode);
 
 		if (msg->flags & USB_8DEV_EXTID)
 			cf->can_id |= CAN_EFF_FLAG;
@@ -637,7 +637,7 @@ static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
 		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(cf, priv->can.ctrlmode);
 	memcpy(msg->data, cf->data, cf->len);
 	msg->end = USB_8DEV_DATA_END;
 
@@ -928,7 +928,8 @@ static int usb_8dev_probe(struct usb_interface *intf,
 	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_ONE_SHOT |
+				      CAN_CTRLMODE_CC_LEN8_DLC;
 
 	netdev->netdev_ops = &usb_8dev_netdev_ops;