can: dev: can_changelink: allow to set bitrate on devices not providing {data_,}bittiming_const

Until commit

    08da7da41e can: provide a separate bittiming_const parameter to
                 bittiming functions

it was possible to have devices not providing bittiming_const. This can
be used for hardware that only support pre-defined fixed bitrates.
Although no mainline driver is using this feature so far.

This patch re-introduces this feature for the bitrate and the data
bitrate (of CANFD controllers). The driver can specify the
{data_,}bittiming_const (if the bittiming parameters should be
calculated from the bittiming_const) as before or no
{data_,}bittiming_const but implement the do_set_{data,}bittiming
callback.

Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Marc Kleine-Budde 2017-01-06 11:12:41 +01:00
parent 12a6075cab
commit c3606d438a
1 changed files with 30 additions and 10 deletions

View File

@ -284,10 +284,6 @@ static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
{
int err;
/* Check if the CAN device has bit-timing parameters */
if (!btc)
return -EOPNOTSUPP;
/*
* Depending on the given can_bittiming parameter structure the CAN
* timing parameters are calculated based on the provided bitrate OR
@ -872,10 +868,22 @@ static int can_changelink(struct net_device *dev,
/* Do not allow changing bittiming while running */
if (dev->flags & IFF_UP)
return -EBUSY;
/* Calculate bittiming parameters based on
* bittiming_const if set, otherwise pass bitrate
* directly via do_set_bitrate(). Bail out if neither
* is given.
*/
if (!priv->bittiming_const && !priv->do_set_bittiming)
return -EOPNOTSUPP;
memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
err = can_get_bittiming(dev, &bt, priv->bittiming_const);
if (err)
return err;
if (priv->bittiming_const) {
err = can_get_bittiming(dev, &bt,
priv->bittiming_const);
if (err)
return err;
}
memcpy(&priv->bittiming, &bt, sizeof(bt));
if (priv->do_set_bittiming) {
@ -943,11 +951,23 @@ static int can_changelink(struct net_device *dev,
/* Do not allow changing bittiming while running */
if (dev->flags & IFF_UP)
return -EBUSY;
/* Calculate bittiming parameters based on
* data_bittiming_const if set, otherwise pass bitrate
* directly via do_set_bitrate(). Bail out if neither
* is given.
*/
if (!priv->data_bittiming_const && !priv->do_set_data_bittiming)
return -EOPNOTSUPP;
memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
sizeof(dbt));
err = can_get_bittiming(dev, &dbt, priv->data_bittiming_const);
if (err)
return err;
if (priv->data_bittiming_const) {
err = can_get_bittiming(dev, &dbt,
priv->data_bittiming_const);
if (err)
return err;
}
memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
if (priv->do_set_data_bittiming) {