Commit 431af779 authored by Marc Kleine-Budde's avatar Marc Kleine-Budde
Browse files

can: dev: add CAN interface API for fixed bitrates 



Some CAN interfaces only support fixed fixed bitrates. This patch adds a
netlink interface to get the list of the CAN interface's fixed bitrates and
data bitrates.

Inside the driver arrays of supported data- bitrate values are defined.

const u32 drvname_bitrate[] = { 20000, 50000, 100000 };
const u32 drvname_data_bitrate[] = { 200000, 500000, 1000000 };

struct drvname_priv *priv;
priv = netdev_priv(dev);

priv->bitrate_const = drvname_bitrate;
priv->bitrate_const_cnt = ARRAY_SIZE(drvname_bitrate);
priv->data_bitrate_const = drvname_data_bitrate;
priv->data_bitrate_const_cnt = ARRAY_SIZE(drvname_data_bitrate);

Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent c3606d43

drivers/net/can/dev.c

+65 −16
Original line number Diff line number Diff line
@@ -279,8 +279,29 @@ static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt, 
	return 0;

}



/* Checks the validity of predefined bitrate settings */

static int can_validate_bitrate(struct net_device *dev, struct can_bittiming *bt,

				const u32 *bitrate_const,

				const unsigned int bitrate_const_cnt)

{

	struct can_priv *priv = netdev_priv(dev);

	unsigned int i;



	for (i = 0; i < bitrate_const_cnt; i++) {

		if (bt->bitrate == bitrate_const[i])

			break;

	}



	if (i >= priv->bitrate_const_cnt)

		return -EINVAL;



	return 0;

}



static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,

			     const struct can_bittiming_const *btc)

			     const struct can_bittiming_const *btc,

			     const u32 *bitrate_const,

			     const unsigned int bitrate_const_cnt)

{

	int err;
@@ -290,10 +311,13 @@ static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt, 
	 * alternatively the CAN timing parameters (tq, prop_seg, etc.) are

	 * provided directly which are then checked and fixed up.

	 */

	if (!bt->tq && bt->bitrate)

	if (!bt->tq && bt->bitrate && btc)

		err = can_calc_bittiming(dev, bt, btc);

	else if (bt->tq && !bt->bitrate)

	else if (bt->tq && !bt->bitrate && btc)

		err = can_fixup_bittiming(dev, bt, btc);

	else if (!bt->tq && bt->bitrate && bitrate_const)

		err = can_validate_bitrate(dev, bt, bitrate_const,

					   bitrate_const_cnt);

	else

		err = -EINVAL;
@@ -878,12 +902,12 @@ static int can_changelink(struct net_device *dev, 
			return -EOPNOTSUPP;



		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));

		if (priv->bittiming_const) {

		err = can_get_bittiming(dev, &bt,

						priv->bittiming_const);

					priv->bittiming_const,

					priv->bitrate_const,

					priv->bitrate_const_cnt);

		if (err)

			return err;

		}

		memcpy(&priv->bittiming, &bt, sizeof(bt));



		if (priv->do_set_bittiming) {
@@ -962,12 +986,12 @@ static int can_changelink(struct net_device *dev, 


		memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),

		       sizeof(dbt));

		if (priv->data_bittiming_const) {

		err = can_get_bittiming(dev, &dbt,

						priv->data_bittiming_const);

					priv->data_bittiming_const,

					priv->data_bitrate_const,

					priv->data_bitrate_const_cnt);

		if (err)

			return err;

		}

		memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));



		if (priv->do_set_data_bittiming) {
@@ -1029,6 +1053,12 @@ static size_t can_get_size(const struct net_device *dev) 
		size += nla_total_size(sizeof(*priv->termination_const) *	/* IFLA_CAN_TERMINATION_CONST */

				       priv->termination_const_cnt);

	}

	if (priv->bitrate_const)				/* IFLA_CAN_BITRATE_CONST */

		size += nla_total_size(sizeof(*priv->bitrate_const) *

				       priv->bitrate_const_cnt);

	if (priv->data_bitrate_const)				/* IFLA_CAN_DATA_BITRATE_CONST */

		size += nla_total_size(sizeof(*priv->data_bitrate_const) *

				       priv->data_bitrate_const_cnt);



	return size;

}
@@ -1074,7 +1104,20 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev) 
	      nla_put(skb, IFLA_CAN_TERMINATION_CONST,

		      sizeof(*priv->termination_const) *

		      priv->termination_const_cnt,

		      priv->termination_const))))

		      priv->termination_const))) ||



	    (priv->bitrate_const &&

	     nla_put(skb, IFLA_CAN_BITRATE_CONST,

		     sizeof(*priv->bitrate_const) *

		     priv->bitrate_const_cnt,

		     priv->bitrate_const)) ||



	    (priv->data_bitrate_const &&

	     nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST,

		     sizeof(*priv->data_bitrate_const) *

		     priv->data_bitrate_const_cnt,

		     priv->data_bitrate_const))

	    )



		return -EMSGSIZE;
@@ -1140,6 +1183,12 @@ int register_candev(struct net_device *dev) 
	    (!priv->termination_const != !priv->do_set_termination))

		return -EINVAL;



	if (!priv->bitrate_const != !priv->bitrate_const_cnt)

		return -EINVAL;



	if (!priv->data_bitrate_const != !priv->data_bitrate_const_cnt)

		return -EINVAL;



	dev->rtnl_link_ops = &can_link_ops;

	return register_netdev(dev);

}

include/linux/can/dev.h

+4 −0
Original line number Diff line number Diff line
@@ -41,6 +41,10 @@ struct can_priv { 
	const u16 *termination_const;

	unsigned int termination_const_cnt;

	u16 termination;

	const u32 *bitrate_const;

	unsigned int bitrate_const_cnt;

	const u32 *data_bitrate_const;

	unsigned int data_bitrate_const_cnt;

	struct can_clock clock;



	enum can_state state;

include/uapi/linux/can/netlink.h

+2 −0
Original line number Diff line number Diff line
@@ -129,6 +129,8 @@ enum { 
	IFLA_CAN_DATA_BITTIMING_CONST,

	IFLA_CAN_TERMINATION,

	IFLA_CAN_TERMINATION_CONST,

	IFLA_CAN_BITRATE_CONST,

	IFLA_CAN_DATA_BITRATE_CONST,

	__IFLA_CAN_MAX

};

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