Factorise the databittiming parsing out of can_changelink() and move
it in the new can_dtb_changelink() function. This is a preparation
patch for the introduction of CAN XL because the databittiming
changelink logic will be reused later on.
Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
---
Changelog:
v1 -> v2:
- Change WARN_ON(1) into return -EOPNOTSUPP to suppress a gcc
warning.
Link: https://lore.kernel.org/linux-can/202509050404.ZLQknagH-lkp@intel.com/
RFC -> v1:
- In the RFC, can_dbt_changelink() required 8 parameters. Instead,
just pass a boolean and then get the FD/XL specific parameters in
an "if (fd) {} else {}" conditional.
---
drivers/net/can/dev/netlink.c | 152 ++++++++++++++++++++++++------------------
1 file changed, 88 insertions(+), 64 deletions(-)
diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
index fde6565fa04af0c5615c09ebb094cbf8bcef3172..5812114ca8842baedebd698d3000843dbce3ec7d 100644
--- a/drivers/net/can/dev/netlink.c
+++ b/drivers/net/can/dev/netlink.c
@@ -220,12 +220,95 @@ static int can_tdc_changelink(struct data_bittiming_params *dbt_params,
return 0;
}
+static int can_dbt_changelink(struct net_device *dev, struct nlattr *data[],
+ bool fd, struct netlink_ext_ack *extack)
+{
+ struct nlattr *data_bittiming, *data_tdc;
+ struct can_priv *priv = netdev_priv(dev);
+ struct data_bittiming_params *dbt_params;
+ struct can_bittiming dbt;
+ bool need_tdc_calc = false;
+ u32 tdc_mask;
+ int err;
+
+ if (fd) {
+ data_bittiming = data[IFLA_CAN_DATA_BITTIMING];
+ data_tdc = data[IFLA_CAN_TDC];
+ dbt_params = &priv->fd;
+ tdc_mask = CAN_CTRLMODE_FD_TDC_MASK;
+ } else {
+ return -EOPNOTSUPP; /* Place holder for CAN XL */
+ }
+
+ if (!data_bittiming)
+ return 0;
+
+ /* 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 (!dbt_params->data_bittiming_const && !dbt_params->do_set_data_bittiming &&
+ !dbt_params->data_bitrate_const)
+ return -EOPNOTSUPP;
+
+ memcpy(&dbt, nla_data(data_bittiming), sizeof(dbt));
+ err = can_get_bittiming(dev, &dbt, dbt_params->data_bittiming_const,
+ dbt_params->data_bitrate_const,
+ dbt_params->data_bitrate_const_cnt, extack);
+ if (err)
+ return err;
+
+ if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
+ NL_SET_ERR_MSG_FMT(extack,
+ "CAN data bitrate %u bps surpasses transceiver capabilities of %u bps",
+ dbt.bitrate, priv->bitrate_max);
+ return -EINVAL;
+ }
+
+ memset(&dbt_params->tdc, 0, sizeof(dbt_params->tdc));
+ if (data[IFLA_CAN_CTRLMODE]) {
+ struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
+
+ need_tdc_calc = !(cm->mask & tdc_mask);
+ }
+ if (data_tdc) {
+ /* TDC parameters are provided: use them */
+ err = can_tdc_changelink(dbt_params, data_tdc, extack);
+ if (err) {
+ priv->ctrlmode &= ~tdc_mask;
+ return err;
+ }
+ } else if (need_tdc_calc) {
+ /* Neither of TDC parameters nor TDC flags are provided:
+ * do calculation
+ */
+ can_calc_tdco(&dbt_params->tdc, dbt_params->tdc_const, &dbt,
+ &priv->ctrlmode, priv->ctrlmode_supported);
+ } /* else: both CAN_CTRLMODE_TDC_{AUTO,MANUAL} are explicitly
+ * turned off. TDC is disabled: do nothing
+ */
+
+ memcpy(&dbt_params->data_bittiming, &dbt, sizeof(dbt));
+
+ if (dbt_params->do_set_data_bittiming) {
+ /* Finally, set the bit-timing registers */
+ err = dbt_params->do_set_data_bittiming(dev);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
static int can_changelink(struct net_device *dev, struct nlattr *tb[],
struct nlattr *data[],
struct netlink_ext_ack *extack)
{
struct can_priv *priv = netdev_priv(dev);
- bool fd_tdc_flag_provided = false;
int err;
/* We need synchronization with dev->stop() */
@@ -273,8 +356,6 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
priv->ctrlmode &= ~CAN_CTRLMODE_FD_TDC_MASK;
memset(&priv->fd.tdc, 0, sizeof(priv->fd.tdc));
}
-
- fd_tdc_flag_provided = cm->mask & CAN_CTRLMODE_FD_TDC_MASK;
}
if (data[IFLA_CAN_BITTIMING]) {
@@ -347,67 +428,10 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
return err;
}
- if (data[IFLA_CAN_DATA_BITTIMING]) {
- struct can_bittiming dbt;
-
- /* 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->fd.data_bittiming_const && !priv->fd.do_set_data_bittiming &&
- !priv->fd.data_bitrate_const)
- return -EOPNOTSUPP;
-
- memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
- sizeof(dbt));
- err = can_get_bittiming(dev, &dbt,
- priv->fd.data_bittiming_const,
- priv->fd.data_bitrate_const,
- priv->fd.data_bitrate_const_cnt,
- extack);
- if (err)
- return err;
-
- if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
- NL_SET_ERR_MSG_FMT(extack,
- "CANFD data bitrate %u bps surpasses transceiver capabilities of %u bps",
- dbt.bitrate, priv->bitrate_max);
- return -EINVAL;
- }
-
- memset(&priv->fd.tdc, 0, sizeof(priv->fd.tdc));
- if (data[IFLA_CAN_TDC]) {
- /* TDC parameters are provided: use them */
- err = can_tdc_changelink(&priv->fd,
- data[IFLA_CAN_TDC], extack);
- if (err) {
- priv->ctrlmode &= ~CAN_CTRLMODE_FD_TDC_MASK;
- return err;
- }
- } else if (!fd_tdc_flag_provided) {
- /* Neither of TDC parameters nor TDC flags are
- * provided: do calculation
- */
- can_calc_tdco(&priv->fd.tdc, priv->fd.tdc_const, &dbt,
- &priv->ctrlmode, priv->ctrlmode_supported);
- } /* else: both CAN_CTRLMODE_TDC_{AUTO,MANUAL} are explicitly
- * turned off. TDC is disabled: do nothing
- */
-
- memcpy(&priv->fd.data_bittiming, &dbt, sizeof(dbt));
-
- if (priv->fd.do_set_data_bittiming) {
- /* Finally, set the bit-timing registers */
- err = priv->fd.do_set_data_bittiming(dev);
- if (err)
- return err;
- }
- }
+ /* CAN FD */
+ err = can_dbt_changelink(dev, data, true, extack);
+ if (err)
+ return err;
if (data[IFLA_CAN_TERMINATION]) {
const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]);
--
2.49.1