can: kvaser_usb: Compare requested bittiming parameters with actual p…

…arameters in do_set_{,data}_bittiming

[ Upstream commit 39d3df6 ]

The device will respond with a CMD_ERROR_EVENT command, with error_code
KVASER_USB_{LEAF,HYDRA}_ERROR_EVENT_PARAM, if the CMD_SET_BUSPARAMS_REQ
contains invalid bittiming parameters.
However, this command does not contain any channel reference.

To check if the CMD_SET_BUSPARAMS_REQ was successful, redback and compare
the requested bittiming parameters with the device reported parameters.

Fixes: 080f40a ("can: kvaser_usb: Add support for Kvaser CAN/USB devices")
Fixes: aec5fb2 ("can: kvaser_usb: Add support for Kvaser USB hydra family")
Tested-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Co-developed-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://lore.kernel.org/all/20221010185237.319219-12-extja@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/can/usb/kvaser_usb/kvaser_usb.h

@@ -119,9 +119,12 @@ struct kvaser_usb_net_priv {
 	struct net_device *netdev;
 	int channel;
 
-	struct completion start_comp, stop_comp, flush_comp;
+	struct completion start_comp, stop_comp, flush_comp,
+			  get_busparams_comp;
 	struct usb_anchor tx_submitted;
 
+	struct kvaser_usb_busparams busparams_nominal, busparams_data;
+
 	spinlock_t tx_contexts_lock; /* lock for active_tx_contexts */
 	int active_tx_contexts;
 	struct kvaser_usb_tx_urb_context tx_contexts[];
@@ -131,7 +134,9 @@ struct kvaser_usb_net_priv {
  * struct kvaser_usb_dev_ops - Device specific functions
  * @dev_set_mode:		used for can.do_set_mode
  * @dev_set_bittiming:		used for can.do_set_bittiming
+ * @dev_get_busparams:		readback arbitration busparams
  * @dev_set_data_bittiming:	used for can.do_set_data_bittiming
+ * @dev_get_data_busparams:	readback data busparams
  * @dev_get_berr_counter:	used for can.do_get_berr_counter
  *
  * @dev_setup_endpoints:	setup USB in and out endpoints
@@ -153,8 +158,12 @@ struct kvaser_usb_net_priv {
  */
 struct kvaser_usb_dev_ops {
 	int (*dev_set_mode)(struct net_device *netdev, enum can_mode mode);
-	int (*dev_set_bittiming)(struct net_device *netdev);
-	int (*dev_set_data_bittiming)(struct net_device *netdev);
+	int (*dev_set_bittiming)(const struct net_device *netdev,
+				 const struct kvaser_usb_busparams *busparams);
+	int (*dev_get_busparams)(struct kvaser_usb_net_priv *priv);
+	int (*dev_set_data_bittiming)(const struct net_device *netdev,
+				      const struct kvaser_usb_busparams *busparams);
+	int (*dev_get_data_busparams)(struct kvaser_usb_net_priv *priv);
 	int (*dev_get_berr_counter)(const struct net_device *netdev,
 				    struct can_berr_counter *bec);
 	int (*dev_setup_endpoints)(struct kvaser_usb *dev);

drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c

@@ -440,10 +440,6 @@ static int kvaser_usb_open(struct net_device *netdev)
 	if (err)
 		return err;
 
-	err = kvaser_usb_setup_rx_urbs(dev);
-	if (err)
-		goto error;
-
 	err = ops->dev_set_opt_mode(priv);
 	if (err)
 		goto error;
@@ -534,6 +530,93 @@ static int kvaser_usb_close(struct net_device *netdev)
 	return 0;
 }
 
+static int kvaser_usb_set_bittiming(struct net_device *netdev)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+	struct kvaser_usb *dev = priv->dev;
+	const struct kvaser_usb_dev_ops *ops = dev->driver_info->ops;
+	struct can_bittiming *bt = &priv->can.bittiming;
+
+	struct kvaser_usb_busparams busparams;
+	int tseg1 = bt->prop_seg + bt->phase_seg1;
+	int tseg2 = bt->phase_seg2;
+	int sjw = bt->sjw;
+	int err = -EOPNOTSUPP;
+
+	busparams.bitrate = cpu_to_le32(bt->bitrate);
+	busparams.sjw = (u8)sjw;
+	busparams.tseg1 = (u8)tseg1;
+	busparams.tseg2 = (u8)tseg2;
+	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+		busparams.nsamples = 3;
+	else
+		busparams.nsamples = 1;
+
+	err = ops->dev_set_bittiming(netdev, &busparams);
+	if (err)
+		return err;
+
+	err = kvaser_usb_setup_rx_urbs(priv->dev);
+	if (err)
+		return err;
+
+	err = ops->dev_get_busparams(priv);
+	if (err) {
+		/* Treat EOPNOTSUPP as success */
+		if (err == -EOPNOTSUPP)
+			err = 0;
+		return err;
+	}
+
+	if (memcmp(&busparams, &priv->busparams_nominal,
+		   sizeof(priv->busparams_nominal)) != 0)
+		err = -EINVAL;
+
+	return err;
+}
+
+static int kvaser_usb_set_data_bittiming(struct net_device *netdev)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+	struct kvaser_usb *dev = priv->dev;
+	const struct kvaser_usb_dev_ops *ops = dev->driver_info->ops;
+	struct can_bittiming *dbt = &priv->can.data_bittiming;
+
+	struct kvaser_usb_busparams busparams;
+	int tseg1 = dbt->prop_seg + dbt->phase_seg1;
+	int tseg2 = dbt->phase_seg2;
+	int sjw = dbt->sjw;
+	int err;
+
+	if (!ops->dev_set_data_bittiming ||
+	    !ops->dev_get_data_busparams)
+		return -EOPNOTSUPP;
+
+	busparams.bitrate = cpu_to_le32(dbt->bitrate);
+	busparams.sjw = (u8)sjw;
+	busparams.tseg1 = (u8)tseg1;
+	busparams.tseg2 = (u8)tseg2;
+	busparams.nsamples = 1;
+
+	err = ops->dev_set_data_bittiming(netdev, &busparams);
+	if (err)
+		return err;
+
+	err = kvaser_usb_setup_rx_urbs(priv->dev);
+	if (err)
+		return err;
+
+	err = ops->dev_get_data_busparams(priv);
+	if (err)
+		return err;
+
+	if (memcmp(&busparams, &priv->busparams_data,
+		   sizeof(priv->busparams_data)) != 0)
+		err = -EINVAL;
+
+	return err;
+}
+
 static void kvaser_usb_write_bulk_callback(struct urb *urb)
 {
 	struct kvaser_usb_tx_urb_context *context = urb->context;
@@ -734,6 +817,7 @@ static int kvaser_usb_init_one(struct kvaser_usb *dev, int channel)
 	init_completion(&priv->start_comp);
 	init_completion(&priv->stop_comp);
 	init_completion(&priv->flush_comp);
+	init_completion(&priv->get_busparams_comp);
 	priv->can.ctrlmode_supported = 0;
 
 	priv->dev = dev;
@@ -746,7 +830,7 @@ static int kvaser_usb_init_one(struct kvaser_usb *dev, int channel)
 	priv->can.state = CAN_STATE_STOPPED;
 	priv->can.clock.freq = dev->cfg->clock.freq;
 	priv->can.bittiming_const = dev->cfg->bittiming_const;
-	priv->can.do_set_bittiming = ops->dev_set_bittiming;
+	priv->can.do_set_bittiming = kvaser_usb_set_bittiming;
 	priv->can.do_set_mode = ops->dev_set_mode;
 	if ((driver_info->quirks & KVASER_USB_QUIRK_HAS_TXRX_ERRORS) ||
 	    (priv->dev->card_data.capabilities & KVASER_USB_CAP_BERR_CAP))
@@ -758,7 +842,7 @@ static int kvaser_usb_init_one(struct kvaser_usb *dev, int channel)
 
 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD) {
 		priv->can.data_bittiming_const = dev->cfg->data_bittiming_const;
-		priv->can.do_set_data_bittiming = ops->dev_set_data_bittiming;
+		priv->can.do_set_data_bittiming = kvaser_usb_set_data_bittiming;
 	}
 
 	netdev->flags |= IFF_ECHO;