can: dev: move bittiming related code into seperate file
This patch moves the bittiming related code of the CAN device infrastructure into a separate file. Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20210111141930.693847-4-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Marc Kleine-Budde
parent
3e77f70e73
commit
5a9d5ecd69
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@ -3943,6 +3943,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can.git
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T: git git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next.git
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T: git git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next.git
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F: Documentation/devicetree/bindings/net/can/
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F: Documentation/devicetree/bindings/net/can/
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F: drivers/net/can/
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F: drivers/net/can/
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F: include/linux/can/bittiming.h
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F: include/linux/can/dev.h
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F: include/linux/can/dev.h
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F: include/linux/can/led.h
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F: include/linux/can/led.h
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F: include/linux/can/platform/
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F: include/linux/can/platform/
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@ -1,6 +1,7 @@
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# SPDX-License-Identifier: GPL-2.0
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# SPDX-License-Identifier: GPL-2.0
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obj-$(CONFIG_CAN_DEV) += can-dev.o
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obj-$(CONFIG_CAN_DEV) += can-dev.o
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can-dev-y += bittiming.o
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can-dev-y += dev.o
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can-dev-y += dev.o
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can-dev-y += rx-offload.o
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can-dev-y += rx-offload.o
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@ -0,0 +1,261 @@
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// SPDX-License-Identifier: GPL-2.0-only
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/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
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* Copyright (C) 2006 Andrey Volkov, Varma Electronics
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* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
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*/
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#include <linux/can/dev.h>
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#ifdef CONFIG_CAN_CALC_BITTIMING
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#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
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/* Bit-timing calculation derived from:
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*
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* Code based on LinCAN sources and H8S2638 project
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* Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
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* Copyright 2005 Stanislav Marek
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* email: pisa@cmp.felk.cvut.cz
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*
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* Calculates proper bit-timing parameters for a specified bit-rate
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* and sample-point, which can then be used to set the bit-timing
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* registers of the CAN controller. You can find more information
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* in the header file linux/can/netlink.h.
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*/
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static int
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can_update_sample_point(const struct can_bittiming_const *btc,
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unsigned int sample_point_nominal, unsigned int tseg,
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unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
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unsigned int *sample_point_error_ptr)
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{
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unsigned int sample_point_error, best_sample_point_error = UINT_MAX;
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unsigned int sample_point, best_sample_point = 0;
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unsigned int tseg1, tseg2;
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int i;
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for (i = 0; i <= 1; i++) {
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tseg2 = tseg + CAN_SYNC_SEG -
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(sample_point_nominal * (tseg + CAN_SYNC_SEG)) /
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1000 - i;
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tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
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tseg1 = tseg - tseg2;
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if (tseg1 > btc->tseg1_max) {
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tseg1 = btc->tseg1_max;
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tseg2 = tseg - tseg1;
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}
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sample_point = 1000 * (tseg + CAN_SYNC_SEG - tseg2) /
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(tseg + CAN_SYNC_SEG);
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sample_point_error = abs(sample_point_nominal - sample_point);
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if (sample_point <= sample_point_nominal &&
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sample_point_error < best_sample_point_error) {
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best_sample_point = sample_point;
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best_sample_point_error = sample_point_error;
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*tseg1_ptr = tseg1;
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*tseg2_ptr = tseg2;
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}
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}
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if (sample_point_error_ptr)
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*sample_point_error_ptr = best_sample_point_error;
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return best_sample_point;
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}
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int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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struct can_priv *priv = netdev_priv(dev);
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unsigned int bitrate; /* current bitrate */
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unsigned int bitrate_error; /* difference between current and nominal value */
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unsigned int best_bitrate_error = UINT_MAX;
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unsigned int sample_point_error; /* difference between current and nominal value */
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unsigned int best_sample_point_error = UINT_MAX;
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unsigned int sample_point_nominal; /* nominal sample point */
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unsigned int best_tseg = 0; /* current best value for tseg */
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unsigned int best_brp = 0; /* current best value for brp */
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unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0;
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u64 v64;
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/* Use CiA recommended sample points */
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if (bt->sample_point) {
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sample_point_nominal = bt->sample_point;
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} else {
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if (bt->bitrate > 800000)
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sample_point_nominal = 750;
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else if (bt->bitrate > 500000)
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sample_point_nominal = 800;
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else
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sample_point_nominal = 875;
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}
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/* tseg even = round down, odd = round up */
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for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
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tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
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tsegall = CAN_SYNC_SEG + tseg / 2;
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/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
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brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
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/* choose brp step which is possible in system */
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brp = (brp / btc->brp_inc) * btc->brp_inc;
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if (brp < btc->brp_min || brp > btc->brp_max)
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continue;
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bitrate = priv->clock.freq / (brp * tsegall);
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bitrate_error = abs(bt->bitrate - bitrate);
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/* tseg brp biterror */
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if (bitrate_error > best_bitrate_error)
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continue;
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/* reset sample point error if we have a better bitrate */
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if (bitrate_error < best_bitrate_error)
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best_sample_point_error = UINT_MAX;
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can_update_sample_point(btc, sample_point_nominal, tseg / 2,
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&tseg1, &tseg2, &sample_point_error);
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if (sample_point_error > best_sample_point_error)
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continue;
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best_sample_point_error = sample_point_error;
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best_bitrate_error = bitrate_error;
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best_tseg = tseg / 2;
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best_brp = brp;
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if (bitrate_error == 0 && sample_point_error == 0)
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break;
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}
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if (best_bitrate_error) {
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/* Error in one-tenth of a percent */
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v64 = (u64)best_bitrate_error * 1000;
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do_div(v64, bt->bitrate);
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bitrate_error = (u32)v64;
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if (bitrate_error > CAN_CALC_MAX_ERROR) {
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netdev_err(dev,
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"bitrate error %d.%d%% too high\n",
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bitrate_error / 10, bitrate_error % 10);
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return -EDOM;
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}
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netdev_warn(dev, "bitrate error %d.%d%%\n",
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bitrate_error / 10, bitrate_error % 10);
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}
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/* real sample point */
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bt->sample_point = can_update_sample_point(btc, sample_point_nominal,
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best_tseg, &tseg1, &tseg2,
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NULL);
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v64 = (u64)best_brp * 1000 * 1000 * 1000;
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do_div(v64, priv->clock.freq);
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bt->tq = (u32)v64;
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bt->prop_seg = tseg1 / 2;
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bt->phase_seg1 = tseg1 - bt->prop_seg;
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bt->phase_seg2 = tseg2;
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/* check for sjw user settings */
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if (!bt->sjw || !btc->sjw_max) {
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bt->sjw = 1;
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} else {
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/* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
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if (bt->sjw > btc->sjw_max)
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bt->sjw = btc->sjw_max;
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/* bt->sjw must not be higher than tseg2 */
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if (tseg2 < bt->sjw)
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bt->sjw = tseg2;
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}
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bt->brp = best_brp;
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/* real bitrate */
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bt->bitrate = priv->clock.freq /
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(bt->brp * (CAN_SYNC_SEG + tseg1 + tseg2));
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return 0;
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}
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#endif /* CONFIG_CAN_CALC_BITTIMING */
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/* Checks the validity of the specified bit-timing parameters prop_seg,
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* phase_seg1, phase_seg2 and sjw and tries to determine the bitrate
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* prescaler value brp. You can find more information in the header
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* file linux/can/netlink.h.
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*/
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static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc)
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{
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struct can_priv *priv = netdev_priv(dev);
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int tseg1, alltseg;
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u64 brp64;
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tseg1 = bt->prop_seg + bt->phase_seg1;
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if (!bt->sjw)
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bt->sjw = 1;
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if (bt->sjw > btc->sjw_max ||
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tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||
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bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max)
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return -ERANGE;
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brp64 = (u64)priv->clock.freq * (u64)bt->tq;
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if (btc->brp_inc > 1)
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do_div(brp64, btc->brp_inc);
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brp64 += 500000000UL - 1;
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do_div(brp64, 1000000000UL); /* the practicable BRP */
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if (btc->brp_inc > 1)
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brp64 *= btc->brp_inc;
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bt->brp = (u32)brp64;
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if (bt->brp < btc->brp_min || bt->brp > btc->brp_max)
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return -EINVAL;
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alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1;
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bt->bitrate = priv->clock.freq / (bt->brp * alltseg);
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bt->sample_point = ((tseg1 + 1) * 1000) / alltseg;
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return 0;
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}
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/* Checks the validity of predefined bitrate settings */
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static int
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can_validate_bitrate(struct net_device *dev, struct can_bittiming *bt,
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const u32 *bitrate_const,
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const unsigned int bitrate_const_cnt)
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{
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struct can_priv *priv = netdev_priv(dev);
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unsigned int i;
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for (i = 0; i < bitrate_const_cnt; i++) {
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if (bt->bitrate == bitrate_const[i])
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break;
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}
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if (i >= priv->bitrate_const_cnt)
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return -EINVAL;
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return 0;
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}
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int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
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const struct can_bittiming_const *btc,
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const u32 *bitrate_const,
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const unsigned int bitrate_const_cnt)
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{
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int err;
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/* Depending on the given can_bittiming parameter structure the CAN
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* timing parameters are calculated based on the provided bitrate OR
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* alternatively the CAN timing parameters (tq, prop_seg, etc.) are
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* provided directly which are then checked and fixed up.
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*/
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if (!bt->tq && bt->bitrate && btc)
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err = can_calc_bittiming(dev, bt, btc);
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else if (bt->tq && !bt->bitrate && btc)
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err = can_fixup_bittiming(dev, bt, btc);
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else if (!bt->tq && bt->bitrate && bitrate_const)
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err = can_validate_bitrate(dev, bt, bitrate_const,
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bitrate_const_cnt);
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else
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err = -EINVAL;
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return err;
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}
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@ -58,267 +58,6 @@ u8 can_fd_len2dlc(u8 len)
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}
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}
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EXPORT_SYMBOL_GPL(can_fd_len2dlc);
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EXPORT_SYMBOL_GPL(can_fd_len2dlc);
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#ifdef CONFIG_CAN_CALC_BITTIMING
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#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
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/* Bit-timing calculation derived from:
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*
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* Code based on LinCAN sources and H8S2638 project
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* Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
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* Copyright 2005 Stanislav Marek
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* email: pisa@cmp.felk.cvut.cz
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*
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* Calculates proper bit-timing parameters for a specified bit-rate
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* and sample-point, which can then be used to set the bit-timing
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* registers of the CAN controller. You can find more information
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* in the header file linux/can/netlink.h.
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*/
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static int
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can_update_sample_point(const struct can_bittiming_const *btc,
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unsigned int sample_point_nominal, unsigned int tseg,
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unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
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unsigned int *sample_point_error_ptr)
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{
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unsigned int sample_point_error, best_sample_point_error = UINT_MAX;
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unsigned int sample_point, best_sample_point = 0;
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unsigned int tseg1, tseg2;
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int i;
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for (i = 0; i <= 1; i++) {
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tseg2 = tseg + CAN_SYNC_SEG -
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(sample_point_nominal * (tseg + CAN_SYNC_SEG)) /
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1000 - i;
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tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
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tseg1 = tseg - tseg2;
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if (tseg1 > btc->tseg1_max) {
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tseg1 = btc->tseg1_max;
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tseg2 = tseg - tseg1;
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}
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sample_point = 1000 * (tseg + CAN_SYNC_SEG - tseg2) /
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(tseg + CAN_SYNC_SEG);
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sample_point_error = abs(sample_point_nominal - sample_point);
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if (sample_point <= sample_point_nominal &&
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sample_point_error < best_sample_point_error) {
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best_sample_point = sample_point;
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best_sample_point_error = sample_point_error;
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*tseg1_ptr = tseg1;
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*tseg2_ptr = tseg2;
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}
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}
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if (sample_point_error_ptr)
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*sample_point_error_ptr = best_sample_point_error;
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return best_sample_point;
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}
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|
||||||
static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
|
|
||||||
const struct can_bittiming_const *btc)
|
|
||||||
{
|
|
||||||
struct can_priv *priv = netdev_priv(dev);
|
|
||||||
unsigned int bitrate; /* current bitrate */
|
|
||||||
unsigned int bitrate_error; /* difference between current and nominal value */
|
|
||||||
unsigned int best_bitrate_error = UINT_MAX;
|
|
||||||
unsigned int sample_point_error; /* difference between current and nominal value */
|
|
||||||
unsigned int best_sample_point_error = UINT_MAX;
|
|
||||||
unsigned int sample_point_nominal; /* nominal sample point */
|
|
||||||
unsigned int best_tseg = 0; /* current best value for tseg */
|
|
||||||
unsigned int best_brp = 0; /* current best value for brp */
|
|
||||||
unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0;
|
|
||||||
u64 v64;
|
|
||||||
|
|
||||||
/* Use CiA recommended sample points */
|
|
||||||
if (bt->sample_point) {
|
|
||||||
sample_point_nominal = bt->sample_point;
|
|
||||||
} else {
|
|
||||||
if (bt->bitrate > 800000)
|
|
||||||
sample_point_nominal = 750;
|
|
||||||
else if (bt->bitrate > 500000)
|
|
||||||
sample_point_nominal = 800;
|
|
||||||
else
|
|
||||||
sample_point_nominal = 875;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* tseg even = round down, odd = round up */
|
|
||||||
for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
|
|
||||||
tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
|
|
||||||
tsegall = CAN_SYNC_SEG + tseg / 2;
|
|
||||||
|
|
||||||
/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
|
|
||||||
brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
|
|
||||||
|
|
||||||
/* choose brp step which is possible in system */
|
|
||||||
brp = (brp / btc->brp_inc) * btc->brp_inc;
|
|
||||||
if (brp < btc->brp_min || brp > btc->brp_max)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
bitrate = priv->clock.freq / (brp * tsegall);
|
|
||||||
bitrate_error = abs(bt->bitrate - bitrate);
|
|
||||||
|
|
||||||
/* tseg brp biterror */
|
|
||||||
if (bitrate_error > best_bitrate_error)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* reset sample point error if we have a better bitrate */
|
|
||||||
if (bitrate_error < best_bitrate_error)
|
|
||||||
best_sample_point_error = UINT_MAX;
|
|
||||||
|
|
||||||
can_update_sample_point(btc, sample_point_nominal, tseg / 2,
|
|
||||||
&tseg1, &tseg2, &sample_point_error);
|
|
||||||
if (sample_point_error > best_sample_point_error)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
best_sample_point_error = sample_point_error;
|
|
||||||
best_bitrate_error = bitrate_error;
|
|
||||||
best_tseg = tseg / 2;
|
|
||||||
best_brp = brp;
|
|
||||||
|
|
||||||
if (bitrate_error == 0 && sample_point_error == 0)
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (best_bitrate_error) {
|
|
||||||
/* Error in one-tenth of a percent */
|
|
||||||
v64 = (u64)best_bitrate_error * 1000;
|
|
||||||
do_div(v64, bt->bitrate);
|
|
||||||
bitrate_error = (u32)v64;
|
|
||||||
if (bitrate_error > CAN_CALC_MAX_ERROR) {
|
|
||||||
netdev_err(dev,
|
|
||||||
"bitrate error %d.%d%% too high\n",
|
|
||||||
bitrate_error / 10, bitrate_error % 10);
|
|
||||||
return -EDOM;
|
|
||||||
}
|
|
||||||
netdev_warn(dev, "bitrate error %d.%d%%\n",
|
|
||||||
bitrate_error / 10, bitrate_error % 10);
|
|
||||||
}
|
|
||||||
|
|
||||||
/* real sample point */
|
|
||||||
bt->sample_point = can_update_sample_point(btc, sample_point_nominal,
|
|
||||||
best_tseg, &tseg1, &tseg2,
|
|
||||||
NULL);
|
|
||||||
|
|
||||||
v64 = (u64)best_brp * 1000 * 1000 * 1000;
|
|
||||||
do_div(v64, priv->clock.freq);
|
|
||||||
bt->tq = (u32)v64;
|
|
||||||
bt->prop_seg = tseg1 / 2;
|
|
||||||
bt->phase_seg1 = tseg1 - bt->prop_seg;
|
|
||||||
bt->phase_seg2 = tseg2;
|
|
||||||
|
|
||||||
/* check for sjw user settings */
|
|
||||||
if (!bt->sjw || !btc->sjw_max) {
|
|
||||||
bt->sjw = 1;
|
|
||||||
} else {
|
|
||||||
/* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
|
|
||||||
if (bt->sjw > btc->sjw_max)
|
|
||||||
bt->sjw = btc->sjw_max;
|
|
||||||
/* bt->sjw must not be higher than tseg2 */
|
|
||||||
if (tseg2 < bt->sjw)
|
|
||||||
bt->sjw = tseg2;
|
|
||||||
}
|
|
||||||
|
|
||||||
bt->brp = best_brp;
|
|
||||||
|
|
||||||
/* real bitrate */
|
|
||||||
bt->bitrate = priv->clock.freq /
|
|
||||||
(bt->brp * (CAN_SYNC_SEG + tseg1 + tseg2));
|
|
||||||
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
#else /* !CONFIG_CAN_CALC_BITTIMING */
|
|
||||||
static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
|
|
||||||
const struct can_bittiming_const *btc)
|
|
||||||
{
|
|
||||||
netdev_err(dev, "bit-timing calculation not available\n");
|
|
||||||
return -EINVAL;
|
|
||||||
}
|
|
||||||
#endif /* CONFIG_CAN_CALC_BITTIMING */
|
|
||||||
|
|
||||||
/* Checks the validity of the specified bit-timing parameters prop_seg,
|
|
||||||
* phase_seg1, phase_seg2 and sjw and tries to determine the bitrate
|
|
||||||
* prescaler value brp. You can find more information in the header
|
|
||||||
* file linux/can/netlink.h.
|
|
||||||
*/
|
|
||||||
static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
|
|
||||||
const struct can_bittiming_const *btc)
|
|
||||||
{
|
|
||||||
struct can_priv *priv = netdev_priv(dev);
|
|
||||||
int tseg1, alltseg;
|
|
||||||
u64 brp64;
|
|
||||||
|
|
||||||
tseg1 = bt->prop_seg + bt->phase_seg1;
|
|
||||||
if (!bt->sjw)
|
|
||||||
bt->sjw = 1;
|
|
||||||
if (bt->sjw > btc->sjw_max ||
|
|
||||||
tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||
|
|
||||||
bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max)
|
|
||||||
return -ERANGE;
|
|
||||||
|
|
||||||
brp64 = (u64)priv->clock.freq * (u64)bt->tq;
|
|
||||||
if (btc->brp_inc > 1)
|
|
||||||
do_div(brp64, btc->brp_inc);
|
|
||||||
brp64 += 500000000UL - 1;
|
|
||||||
do_div(brp64, 1000000000UL); /* the practicable BRP */
|
|
||||||
if (btc->brp_inc > 1)
|
|
||||||
brp64 *= btc->brp_inc;
|
|
||||||
bt->brp = (u32)brp64;
|
|
||||||
|
|
||||||
if (bt->brp < btc->brp_min || bt->brp > btc->brp_max)
|
|
||||||
return -EINVAL;
|
|
||||||
|
|
||||||
alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1;
|
|
||||||
bt->bitrate = priv->clock.freq / (bt->brp * alltseg);
|
|
||||||
bt->sample_point = ((tseg1 + 1) * 1000) / alltseg;
|
|
||||||
|
|
||||||
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 u32 *bitrate_const,
|
|
||||||
const unsigned int bitrate_const_cnt)
|
|
||||||
{
|
|
||||||
int err;
|
|
||||||
|
|
||||||
/* Depending on the given can_bittiming parameter structure the CAN
|
|
||||||
* timing parameters are calculated based on the provided bitrate OR
|
|
||||||
* alternatively the CAN timing parameters (tq, prop_seg, etc.) are
|
|
||||||
* provided directly which are then checked and fixed up.
|
|
||||||
*/
|
|
||||||
if (!bt->tq && bt->bitrate && btc)
|
|
||||||
err = can_calc_bittiming(dev, bt, btc);
|
|
||||||
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;
|
|
||||||
|
|
||||||
return err;
|
|
||||||
}
|
|
||||||
|
|
||||||
static void can_update_state_error_stats(struct net_device *dev,
|
static void can_update_state_error_stats(struct net_device *dev,
|
||||||
enum can_state new_state)
|
enum can_state new_state)
|
||||||
{
|
{
|
||||||
|
|
|
||||||
|
|
@ -0,0 +1,44 @@
|
||||||
|
/* SPDX-License-Identifier: GPL-2.0-only */
|
||||||
|
/* Copyright (c) 2020 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de>
|
||||||
|
*/
|
||||||
|
|
||||||
|
#ifndef _CAN_BITTIMING_H
|
||||||
|
#define _CAN_BITTIMING_H
|
||||||
|
|
||||||
|
#include <linux/netdevice.h>
|
||||||
|
#include <linux/can/netlink.h>
|
||||||
|
|
||||||
|
#define CAN_SYNC_SEG 1
|
||||||
|
|
||||||
|
#ifdef CONFIG_CAN_CALC_BITTIMING
|
||||||
|
int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
|
||||||
|
const struct can_bittiming_const *btc);
|
||||||
|
#else /* !CONFIG_CAN_CALC_BITTIMING */
|
||||||
|
static inline int
|
||||||
|
can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
|
||||||
|
const struct can_bittiming_const *btc)
|
||||||
|
{
|
||||||
|
netdev_err(dev, "bit-timing calculation not available\n");
|
||||||
|
return -EINVAL;
|
||||||
|
}
|
||||||
|
#endif /* CONFIG_CAN_CALC_BITTIMING */
|
||||||
|
|
||||||
|
int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
|
||||||
|
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 */
|
||||||
|
|
@ -15,6 +15,7 @@
|
||||||
#define _CAN_DEV_H
|
#define _CAN_DEV_H
|
||||||
|
|
||||||
#include <linux/can.h>
|
#include <linux/can.h>
|
||||||
|
#include <linux/can/bittiming.h>
|
||||||
#include <linux/can/error.h>
|
#include <linux/can/error.h>
|
||||||
#include <linux/can/led.h>
|
#include <linux/can/led.h>
|
||||||
#include <linux/can/netlink.h>
|
#include <linux/can/netlink.h>
|
||||||
|
|
@ -82,21 +83,6 @@ struct can_priv {
|
||||||
#endif
|
#endif
|
||||||
};
|
};
|
||||||
|
|
||||||
#define CAN_SYNC_SEG 1
|
|
||||||
|
|
||||||
/*
|
|
||||||
* 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;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* can_cc_dlc2len(value) - convert a given data length code (dlc) of a
|
* can_cc_dlc2len(value) - convert a given data length code (dlc) of a
|
||||||
* Classical CAN frame into a valid data length of max. 8 bytes.
|
* Classical CAN frame into a valid data length of max. 8 bytes.
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue