static u64 ines_find_txts()

in ptp_ines.c [285:329]

• 38 lines of code
• 5 McCabe index (conditional complexity)

static u64 ines_find_txts(struct ines_port *port, struct sk_buff *skb)
{
	unsigned int class = ptp_classify_raw(skb), i;
	u32 data_rd_pos, buf_stat, mask, ts_stat_tx;
	struct ines_timestamp ts;
	unsigned long flags;
	u64 ns = 0;

	mask = TX_FIFO_NE_1 << port->index;

	spin_lock_irqsave(&port->lock, flags);

	for (i = 0; i < INES_FIFO_DEPTH; i++) {

		buf_stat = ines_read32(port->clock, buf_stat);
		if (!(buf_stat & mask)) {
			dev_dbg(port->clock->dev,
				  "Tx timestamp FIFO unexpectedly empty\n");
			break;
		}
		ts_stat_tx = ines_read32(port, ts_stat_tx);
		data_rd_pos = (ts_stat_tx >> DATA_READ_POS_SHIFT) &
			DATA_READ_POS_MASK;
		if (data_rd_pos) {
			dev_err(port->clock->dev,
				"unexpected Tx read pos %u\n", data_rd_pos);
			break;
		}

		ts.tag     = ines_read32(port, ts_tx);
		ts.sec     = ines_txts64(port, 3);
		ts.nsec    = ines_txts64(port, 2);
		ts.clkid   = ines_txts64(port, 4);
		ts.portnum = ines_read32(port, ts_tx);
		ts.seqid   = ines_read32(port, ts_tx);

		if (ines_match(skb, class, &ts, port->clock->dev)) {
			ns = ts.sec * 1000000000ULL + ts.nsec;
			break;
		}
	}

	spin_unlock_irqrestore(&port->lock, flags);
	return ns;
}