can: dev: make can_get_relative_tdco() FD agnostic and move it to bittiming.h

can_get_relative_tdco() needs to access can_priv->fd making it
specific to CAN FD. Change the function parameter from struct can_priv
to struct data_bittiming_params. This way, the function becomes CAN FD
agnostic and can be reused later on for the CAN XL TDC.

Now that we dropped the dependency on struct can_priv, also move
can_get_relative_tdco() back to bittiming.h where it was meant to
belong to.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-2-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/include/linux/can/bittiming.h b/include/linux/can/bittiming.h
index 6572ec1712ca2df8db7fe1453ae5a4d5699712b1..4d5f7794194ab13641c7854c2d66625c4e942f6c 100644 (file)
--- a/include/linux/can/bittiming.h
+++ b/include/linux/can/bittiming.h
@@ -160,6 +160,35 @@ int can_get_bittiming(const struct net_device *dev, struct can_bittiming *bt,
                      const unsigned int bitrate_const_cnt,
                      struct netlink_ext_ack *extack);
 
+/*
+ * can_get_relative_tdco() - TDCO relative to the sample point
+ *
+ * struct can_tdc::tdco represents the absolute offset from TDCV. Some
+ * controllers use instead an offset relative to the Sample Point (SP)
+ * such that:
+ *
+ * SSP = TDCV + absolute TDCO
+ *     = TDCV + SP + relative TDCO
+ *
+ * -+----------- one bit ----------+-- TX pin
+ *  |<--- Sample Point --->|
+ *
+ *                         --+----------- one bit ----------+-- RX pin
+ *  |<-------- TDCV -------->|
+ *                           |<------------------------>| absolute TDCO
+ *                           |<--- Sample Point --->|
+ *                           |                      |<->| relative TDCO
+ *  |<------------- Secondary Sample Point ------------>|
+ */
+static inline s32 can_get_relative_tdco(const struct data_bittiming_params *dbt_params)
+{
+       const struct can_bittiming *dbt = &dbt_params->data_bittiming;
+       s32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg +
+                                 dbt->phase_seg1) * dbt->brp;
+
+       return (s32)dbt_params->tdc.tdco - sample_point_in_tc;
+}
+
 /*
  * can_bit_time() - Duration of one bit
  *

diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index c2fe956ab7761f45a87e77131bb57e9d5d51dd7f..8e75e9b3830a7a0dab16b6450622fc4a98219a9c 100644 (file)
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -85,35 +85,6 @@ static inline bool can_fd_tdc_is_enabled(const struct can_priv *priv)
        return !!(priv->ctrlmode & CAN_CTRLMODE_FD_TDC_MASK);
 }
 
-/*
- * can_get_relative_tdco() - TDCO relative to the sample point
- *
- * struct can_tdc::tdco represents the absolute offset from TDCV. Some
- * controllers use instead an offset relative to the Sample Point (SP)
- * such that:
- *
- * SSP = TDCV + absolute TDCO
- *     = TDCV + SP + relative TDCO
- *
- * -+----------- one bit ----------+-- TX pin
- *  |<--- Sample Point --->|
- *
- *                         --+----------- one bit ----------+-- RX pin
- *  |<-------- TDCV -------->|
- *                           |<------------------------>| absolute TDCO
- *                           |<--- Sample Point --->|
- *                           |                      |<->| relative TDCO
- *  |<------------- Secondary Sample Point ------------>|
- */
-static inline s32 can_get_relative_tdco(const struct can_priv *priv)
-{
-       const struct can_bittiming *dbt = &priv->fd.data_bittiming;
-       s32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg +
-                                 dbt->phase_seg1) * dbt->brp;
-
-       return (s32)priv->fd.tdc.tdco - sample_point_in_tc;
-}
-
 static inline u32 can_get_static_ctrlmode(struct can_priv *priv)
 {
        return priv->ctrlmode & ~priv->ctrlmode_supported;