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can-calc-bit-timint: rename spt_target, sample_point -> spt_nominal 

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
pull/17/head
Marc Kleine-Budde 2016-04-15 11:13:43 +02:00
parent 44a2900bd8
commit 798afd077a
1 changed files with 18 additions and 18 deletions
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36
can-calc-bit-timing.c
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@ -548,7 +548,7 @@ static long common_bitrates[] = {
* in the header file linux/can/netlink.h. * in the header file linux/can/netlink.h.
*/ */
static int can_update_spt(const struct can_bittiming_const *btc, static int can_update_spt(const struct can_bittiming_const *btc,
unsigned int spt_target, unsigned int tseg, unsigned int spt_nominal, unsigned int tseg,
unsigned int *tseg1_ptr, unsigned int *tseg2_ptr, unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
unsigned int *spt_error_ptr) unsigned int *spt_error_ptr)
{ {
@ -558,7 +558,7 @@ static int can_update_spt(const struct can_bittiming_const *btc,
int i; int i;
for (i = 0; i <= 1; i++) { for (i = 0; i <= 1; i++) {
tseg2 = tseg + CAN_CALC_SYNC_SEG - (spt_target * (tseg + CAN_CALC_SYNC_SEG)) / 1000 - i; tseg2 = tseg + CAN_CALC_SYNC_SEG - (spt_nominal * (tseg + CAN_CALC_SYNC_SEG)) / 1000 - i;
tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max); tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
tseg1 = tseg - tseg2; tseg1 = tseg - tseg2;
if (tseg1 > btc->tseg1_max) { if (tseg1 > btc->tseg1_max) {
@ -567,9 +567,9 @@ static int can_update_spt(const struct can_bittiming_const *btc,
} }
spt = 1000 * (tseg + CAN_CALC_SYNC_SEG - tseg2) / (tseg + CAN_CALC_SYNC_SEG); spt = 1000 * (tseg + CAN_CALC_SYNC_SEG - tseg2) / (tseg + CAN_CALC_SYNC_SEG);
spt_error = abs(spt_target - spt); spt_error = abs(spt_nominal - spt);
if ((spt <= spt_target) && (spt_error < best_spt_error)) { if ((spt <= spt_nominal) && (spt_error < best_spt_error)) {
best_spt = spt; best_spt = spt;
best_spt_error = spt_error; best_spt_error = spt_error;
*tseg1_ptr = tseg1; *tseg1_ptr = tseg1;
@ -588,11 +588,11 @@ static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
{ {
struct can_priv *priv = netdev_priv(dev); struct can_priv *priv = netdev_priv(dev);
unsigned int rate; /* current bitrate */ unsigned int rate; /* current bitrate */
unsigned int rate_error; /* difference between current and target value */ unsigned int rate_error; /* difference between current and nominal value */
unsigned int best_rate_error = UINT_MAX; unsigned int best_rate_error = UINT_MAX;
unsigned int spt_error; /* difference between current and target value */ unsigned int spt_error; /* difference between current and nominal value */
unsigned int best_spt_error = UINT_MAX; unsigned int best_spt_error = UINT_MAX;
unsigned int spt_target; /* target sample point */ unsigned int spt_nominal; /* nominal sample point */
unsigned int best_tseg = 0; /* current best value for tseg */ unsigned int best_tseg = 0; /* current best value for tseg */
unsigned int best_brp = 0; /* current best value for brp */ unsigned int best_brp = 0; /* current best value for brp */
unsigned int brp, tsegall, tseg, tseg1, tseg2; unsigned int brp, tsegall, tseg, tseg1, tseg2;
@ -600,14 +600,14 @@ static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
/* Use CiA recommended sample points */ /* Use CiA recommended sample points */
if (bt->sample_point) { if (bt->sample_point) {
spt_target = bt->sample_point; spt_nominal = bt->sample_point;
} else { } else {
if (bt->bitrate > 800000) if (bt->bitrate > 800000)
spt_target = 750; spt_nominal = 750;
else if (bt->bitrate > 500000) else if (bt->bitrate > 500000)
spt_target = 800; spt_nominal = 800;
else else
spt_target = 875; spt_nominal = 875;
} }
/* tseg even = round down, odd = round up */ /* tseg even = round down, odd = round up */
@ -634,7 +634,7 @@ static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
if (rate_error < best_rate_error) if (rate_error < best_rate_error)
best_spt_error = UINT_MAX; best_spt_error = UINT_MAX;
can_update_spt(btc, spt_target, tseg / 2, &tseg1, &tseg2, &spt_error); can_update_spt(btc, spt_nominal, tseg / 2, &tseg1, &tseg2, &spt_error);
if (spt_error > best_spt_error) if (spt_error > best_spt_error)
continue; continue;
@ -661,7 +661,7 @@ static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
} }
/* real sample point */ /* real sample point */
bt->sample_point = can_update_spt(btc, spt_target, best_tseg, bt->sample_point = can_update_spt(btc, spt_nominal, best_tseg,
&tseg1, &tseg2, NULL); &tseg1, &tseg2, NULL);
v64 = (u64)best_brp * 1000 * 1000 * 1000; v64 = (u64)best_brp * 1000 * 1000 * 1000;
@ -773,7 +773,7 @@ int main(int argc, char *argv[])
{ {
__u32 bitrate = 0; __u32 bitrate = 0;
__u32 opt_ref_clk = 0, ref_clk; __u32 opt_ref_clk = 0, ref_clk;
unsigned int spt_target = 0; unsigned int spt_nominal = 0;
bool quiet = false, list = false, found = false; bool quiet = false, list = false, found = false;
char *name = NULL; char *name = NULL;
unsigned int i, j; unsigned int i, j;
@ -800,7 +800,7 @@ int main(int argc, char *argv[])
break; break;
case 's': case 's':
spt_target = strtoul(optarg, NULL, 10); spt_nominal = strtoul(optarg, NULL, 10);
break; break;
default: default:
@ -820,7 +820,7 @@ int main(int argc, char *argv[])
exit(EXIT_SUCCESS); exit(EXIT_SUCCESS);
} }
if (spt_target && (spt_target >= 1000 || spt_target < 100)) if (spt_nominal && (spt_nominal >= 1000 || spt_nominal < 100))
print_usage(argv[0]); print_usage(argv[0]);
for (i = 0; i < ARRAY_SIZE(can_calc_consts); i++) { for (i = 0; i < ARRAY_SIZE(can_calc_consts); i++) {
@ -836,11 +836,11 @@ int main(int argc, char *argv[])
ref_clk = btc->ref_clk; ref_clk = btc->ref_clk;
if (bitrate) { if (bitrate) {
print_bit_timing(btc, bitrate, spt_target, ref_clk, quiet); print_bit_timing(btc, bitrate, spt_nominal, ref_clk, quiet);
} else { } else {
for (j = 0; j < ARRAY_SIZE(common_bitrates); j++) for (j = 0; j < ARRAY_SIZE(common_bitrates); j++)
print_bit_timing(btc, common_bitrates[j], print_bit_timing(btc, common_bitrates[j],
spt_target, ref_clk, j); spt_nominal, ref_clk, j);
} }
printf("\n"); printf("\n");
} }