1 files changed, 6 insertions, 206 deletions

diff --git a/drivers/net/can/dev/bittiming.c b/drivers/net/can/dev/bittiming.c
index 0509625c3082..7ae80763c960 100644
--- a/drivers/net/can/dev/bittiming.c
+++ b/drivers/net/can/dev/bittiming.c
@@ -6,211 +6,15 @@
 
 #include <linux/can/dev.h>
 
-#ifdef CONFIG_CAN_CALC_BITTIMING
-#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
-
-/* Bit-timing calculation derived from:
- *
- * Code based on LinCAN sources and H8S2638 project
- * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
- * Copyright 2005      Stanislav Marek
- * email: pisa@cmp.felk.cvut.cz
- *
- * Calculates proper bit-timing parameters for a specified bit-rate
- * and sample-point, which can then be used to set the bit-timing
- * registers of the CAN controller. You can find more information
- * in the header file linux/can/netlink.h.
- */
-static int
-can_update_sample_point(const struct can_bittiming_const *btc,
-			unsigned int sample_point_nominal, unsigned int tseg,
-			unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
-			unsigned int *sample_point_error_ptr)
-{
-	unsigned int sample_point_error, best_sample_point_error = UINT_MAX;
-	unsigned int sample_point, best_sample_point = 0;
-	unsigned int tseg1, tseg2;
-	int i;
-
-	for (i = 0; i <= 1; i++) {
-		tseg2 = tseg + CAN_SYNC_SEG -
-			(sample_point_nominal * (tseg + CAN_SYNC_SEG)) /
-			1000 - i;
-		tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
-		tseg1 = tseg - tseg2;
-		if (tseg1 > btc->tseg1_max) {
-			tseg1 = btc->tseg1_max;
-			tseg2 = tseg - tseg1;
-		}
-
-		sample_point = 1000 * (tseg + CAN_SYNC_SEG - tseg2) /
-			(tseg + CAN_SYNC_SEG);
-		sample_point_error = abs(sample_point_nominal - sample_point);
-
-		if (sample_point <= sample_point_nominal &&
-		    sample_point_error < best_sample_point_error) {
-			best_sample_point = sample_point;
-			best_sample_point_error = sample_point_error;
-			*tseg1_ptr = tseg1;
-			*tseg2_ptr = tseg2;
-		}
-	}
-
-	if (sample_point_error_ptr)
-		*sample_point_error_ptr = best_sample_point_error;
-
-	return best_sample_point;
-}
-
-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 > 800 * CAN_KBPS)
-			sample_point_nominal = 750;
-		else if (bt->bitrate > 500 * CAN_KBPS)
-			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;
-}
-
-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)
-
-{
-	if (!tdc_const || !(ctrlmode_supported & CAN_CTRLMODE_TDC_AUTO))
-		return;
-
-	*ctrlmode &= ~CAN_CTRLMODE_TDC_MASK;
-
-	/* As specified in ISO 11898-1 section 11.3.3 "Transmitter
-	 * delay compensation" (TDC) is only applicable if data BRP is
-	 * one or two.
-	 */
-	if (dbt->brp == 1 || dbt->brp == 2) {
-		/* Sample point in clock periods */
-		u32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg +
-					  dbt->phase_seg1) * dbt->brp;
-
-		if (sample_point_in_tc < tdc_const->tdco_min)
-			return;
-		tdc->tdco = min(sample_point_in_tc, tdc_const->tdco_max);
-		*ctrlmode |= CAN_CTRLMODE_TDC_AUTO;
-	}
-}
-#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,
+static int can_fixup_bittiming(const struct net_device *dev, struct can_bittiming *bt,
 			       const struct can_bittiming_const *btc)
 {
-	struct can_priv *priv = netdev_priv(dev);
+	const struct can_priv *priv = netdev_priv(dev);
 	unsigned int tseg1, alltseg;
 	u64 brp64;
 
@@ -243,25 +47,21 @@ static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
 
 /* Checks the validity of predefined bitrate settings */
 static int
-can_validate_bitrate(struct net_device *dev, struct can_bittiming *bt,
+can_validate_bitrate(const struct net_device *dev, const 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;
+			return 0;
 	}
 
-	if (i >= priv->bitrate_const_cnt)
-		return -EINVAL;
-
-	return 0;
+	return -EINVAL;
 }
 
-int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
+int can_get_bittiming(const struct net_device *dev, struct can_bittiming *bt,
 		      const struct can_bittiming_const *btc,
 		      const u32 *bitrate_const,
 		      const unsigned int bitrate_const_cnt)