diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/dsa/sja1105/sja1105_ptp.c | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/drivers/net/dsa/sja1105/sja1105_ptp.c b/drivers/net/dsa/sja1105/sja1105_ptp.c index a22f8e3fc06b..bc0e47c1dbb9 100644 --- a/drivers/net/dsa/sja1105/sja1105_ptp.c +++ b/drivers/net/dsa/sja1105/sja1105_ptp.c @@ -16,14 +16,15 @@ /* PTPSYNCTS has no interrupt or update mechanism, because the intended * hardware use case is for the timestamp to be collected synchronously, - * immediately after the CAS_MASTER SJA1105 switch has triggered a CASSYNC - * pulse on the PTP_CLK pin. When used as a generic extts source, it needs - * polling and a comparison with the old value. The polling interval is just - * the Nyquist rate of a canonical PPS input (e.g. from a GPS module). - * Anything of higher frequency than 1 Hz will be lost, since there is no - * timestamp FIFO. + * immediately after the CAS_MASTER SJA1105 switch has performed a CASSYNC + * one-shot toggle (no return to level) on the PTP_CLK pin. When used as a + * generic extts source, the PTPSYNCTS register needs polling and a comparison + * with the old value. The polling interval is configured as the Nyquist rate + * of a signal with 50% duty cycle and 1Hz frequency, which is sadly all that + * this hardware can do (but may be enough for some setups). Anything of higher + * frequency than 1 Hz will be lost, since there is no timestamp FIFO. */ -#define SJA1105_EXTTS_INTERVAL (HZ / 2) +#define SJA1105_EXTTS_INTERVAL (HZ / 4) /* This range is actually +/- SJA1105_MAX_ADJ_PPB * divided by 1000 (ppb -> ppm) and with a 16-bit @@ -754,7 +755,16 @@ static int sja1105_extts_enable(struct sja1105_private *priv, return -EOPNOTSUPP; /* Reject requests with unsupported flags */ - if (extts->flags) + if (extts->flags & ~(PTP_ENABLE_FEATURE | + PTP_RISING_EDGE | + PTP_FALLING_EDGE | + PTP_STRICT_FLAGS)) + return -EOPNOTSUPP; + + /* We can only enable time stamping on both edges, sadly. */ + if ((extts->flags & PTP_STRICT_FLAGS) && + (extts->flags & PTP_ENABLE_FEATURE) && + (extts->flags & PTP_EXTTS_EDGES) != PTP_EXTTS_EDGES) return -EOPNOTSUPP; rc = sja1105_change_ptp_clk_pin_func(priv, PTP_PF_EXTTS); |