2021-01-11 14:19:18 +00:00
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/* SPDX-License-Identifier: GPL-2.0-only */
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/* Copyright (c) 2020 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de>
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2021-02-24 00:20:04 +00:00
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* Copyright (c) 2021 Vincent Mailhol <mailhol.vincent@wanadoo.fr>
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2021-01-11 14:19:18 +00:00
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*/
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#ifndef _CAN_BITTIMING_H
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#define _CAN_BITTIMING_H
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#include <linux/netdevice.h>
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#include <linux/can/netlink.h>
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#define CAN_SYNC_SEG 1
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2022-06-28 16:31:28 +00:00
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#define CAN_BITRATE_UNSET 0
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#define CAN_BITRATE_UNKNOWN (-1U)
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2021-03-06 05:40:40 +00:00
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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#define CAN_CTRLMODE_TDC_MASK \
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(CAN_CTRLMODE_TDC_AUTO | CAN_CTRLMODE_TDC_MANUAL)
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2021-02-24 00:20:04 +00:00
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/*
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* struct can_tdc - CAN FD Transmission Delay Compensation parameters
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*
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* At high bit rates, the propagation delay from the TX pin to the RX
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* pin of the transceiver causes measurement errors: the sample point
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* on the RX pin might occur on the previous bit.
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*
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* To solve this issue, ISO 11898-1 introduces in section 11.3.3
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* "Transmitter delay compensation" a SSP (Secondary Sample Point)
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2021-09-18 09:56:33 +00:00
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* equal to the distance from the start of the bit time on the TX pin
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* to the actual measurement on the RX pin.
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2021-02-24 00:20:04 +00:00
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*
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* This structure contains the parameters to calculate that SSP.
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*
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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* -+----------- one bit ----------+-- TX pin
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* |<--- Sample Point --->|
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*
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* --+----------- one bit ----------+-- RX pin
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* |<-------- TDCV -------->|
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* |<------- TDCO ------->|
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* |<----------- Secondary Sample Point ---------->|
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*
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2021-09-18 09:56:33 +00:00
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* To increase precision, contrary to the other bittiming parameters
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* which are measured in time quanta, the TDC parameters are measured
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* in clock periods (also referred as "minimum time quantum" in ISO
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* 11898-1).
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*
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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* @tdcv: Transmitter Delay Compensation Value. The time needed for
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2021-09-18 09:56:33 +00:00
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* the signal to propagate, i.e. the distance, in clock periods,
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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* from the start of the bit on the TX pin to when it is received
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* on the RX pin. @tdcv depends on the controller modes:
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*
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* CAN_CTRLMODE_TDC_AUTO is set: The transceiver dynamically
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* measures @tdcv for each transmitted CAN FD frame and the
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* value provided here should be ignored.
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2021-02-24 00:20:04 +00:00
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*
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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* CAN_CTRLMODE_TDC_MANUAL is set: use the fixed provided @tdcv
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* value.
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2021-02-24 00:20:04 +00:00
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*
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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* N.B. CAN_CTRLMODE_TDC_AUTO and CAN_CTRLMODE_TDC_MANUAL are
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* mutually exclusive. Only one can be set at a time. If both
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* CAN_TDC_CTRLMODE_AUTO and CAN_TDC_CTRLMODE_MANUAL are unset,
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* TDC is disabled and all the values of this structure should be
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* ignored.
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2021-02-24 00:20:04 +00:00
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*
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2021-09-18 09:56:33 +00:00
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* @tdco: Transmitter Delay Compensation Offset. Offset value, in
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* clock periods, defining the distance between the start of the
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* bit reception on the RX pin of the transceiver and the SSP
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2021-06-16 09:55:26 +00:00
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* position such that SSP = @tdcv + @tdco.
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2021-02-24 00:20:04 +00:00
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*
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* @tdcf: Transmitter Delay Compensation Filter window. Defines the
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2021-09-18 09:56:33 +00:00
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* minimum value for the SSP position in clock periods. If the
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* SSP position is less than @tdcf, then no delay compensations
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* occur and the normal sampling point is used instead. The
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* feature is enabled if and only if @tdcv is set to zero
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* (automatic mode) and @tdcf is configured to a value greater
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* than @tdco.
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2021-02-24 00:20:04 +00:00
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*/
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struct can_tdc {
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u32 tdcv;
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u32 tdco;
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u32 tdcf;
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};
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/*
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* struct can_tdc_const - CAN hardware-dependent constant for
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* Transmission Delay Compensation
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*
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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* @tdcv_min: Transmitter Delay Compensation Value minimum value. If
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* the controller does not support manual mode for tdcv
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* (c.f. flag CAN_CTRLMODE_TDC_MANUAL) then this value is
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* ignored.
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* @tdcv_max: Transmitter Delay Compensation Value maximum value. If
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* the controller does not support manual mode for tdcv
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* (c.f. flag CAN_CTRLMODE_TDC_MANUAL) then this value is
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* ignored.
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*
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* @tdco_min: Transmitter Delay Compensation Offset minimum value.
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2021-02-24 00:20:04 +00:00
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* @tdco_max: Transmitter Delay Compensation Offset maximum value.
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* Should not be zero. If the controller does not support TDC,
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* then the pointer to this structure should be NULL.
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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*
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* @tdcf_min: Transmitter Delay Compensation Filter window minimum
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* value. If @tdcf_max is zero, this value is ignored.
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2021-02-24 00:20:04 +00:00
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* @tdcf_max: Transmitter Delay Compensation Filter window maximum
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* value. Should be set to zero if the controller does not
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* support this feature.
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*/
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struct can_tdc_const {
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can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
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u32 tdcv_min;
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2021-02-24 00:20:04 +00:00
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|
u32 tdcv_max;
|
can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
|
|
|
u32 tdco_min;
|
2021-02-24 00:20:04 +00:00
|
|
|
u32 tdco_max;
|
can: bittiming: allow TDC{V,O} to be zero and add can_tdc_const::tdc{v,o,f}_min
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-09-18 09:56:32 +00:00
|
|
|
u32 tdcf_min;
|
2021-02-24 00:20:04 +00:00
|
|
|
u32 tdcf_max;
|
|
|
|
};
|
|
|
|
|
2021-01-11 14:19:18 +00:00
|
|
|
#ifdef CONFIG_CAN_CALC_BITTIMING
|
2022-01-13 14:34:07 +00:00
|
|
|
int can_calc_bittiming(const struct net_device *dev, struct can_bittiming *bt,
|
2021-01-11 14:19:18 +00:00
|
|
|
const struct can_bittiming_const *btc);
|
2021-02-24 00:20:08 +00:00
|
|
|
|
2021-09-18 09:56:34 +00:00
|
|
|
void can_calc_tdco(struct can_tdc *tdc, const struct can_tdc_const *tdc_const,
|
|
|
|
const struct can_bittiming *dbt,
|
|
|
|
u32 *ctrlmode, u32 ctrlmode_supported);
|
2021-01-11 14:19:18 +00:00
|
|
|
#else /* !CONFIG_CAN_CALC_BITTIMING */
|
|
|
|
static inline int
|
2022-01-13 14:34:07 +00:00
|
|
|
can_calc_bittiming(const struct net_device *dev, struct can_bittiming *bt,
|
2021-01-11 14:19:18 +00:00
|
|
|
const struct can_bittiming_const *btc)
|
|
|
|
{
|
|
|
|
netdev_err(dev, "bit-timing calculation not available\n");
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
2021-02-24 00:20:08 +00:00
|
|
|
|
2021-09-18 09:56:34 +00:00
|
|
|
static inline void
|
|
|
|
can_calc_tdco(struct can_tdc *tdc, const struct can_tdc_const *tdc_const,
|
|
|
|
const struct can_bittiming *dbt,
|
|
|
|
u32 *ctrlmode, u32 ctrlmode_supported)
|
2021-02-24 00:20:08 +00:00
|
|
|
{
|
|
|
|
}
|
2021-01-11 14:19:18 +00:00
|
|
|
#endif /* CONFIG_CAN_CALC_BITTIMING */
|
|
|
|
|
2022-01-13 14:34:07 +00:00
|
|
|
int can_get_bittiming(const struct net_device *dev, struct can_bittiming *bt,
|
2021-01-11 14:19:18 +00:00
|
|
|
const struct can_bittiming_const *btc,
|
|
|
|
const u32 *bitrate_const,
|
|
|
|
const unsigned int bitrate_const_cnt);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* can_bit_time() - Duration of one bit
|
|
|
|
*
|
|
|
|
* Please refer to ISO 11898-1:2015, section 11.3.1.1 "Bit time" for
|
|
|
|
* additional information.
|
|
|
|
*
|
|
|
|
* Return: the number of time quanta in one bit.
|
|
|
|
*/
|
|
|
|
static inline unsigned int can_bit_time(const struct can_bittiming *bt)
|
|
|
|
{
|
|
|
|
return CAN_SYNC_SEG + bt->prop_seg + bt->phase_seg1 + bt->phase_seg2;
|
|
|
|
}
|
|
|
|
|
|
|
|
#endif /* !_CAN_BITTIMING_H */
|