static int dw_i3c_master_daa()

in master/dw-i3c-master.c [761:824]

• 51 lines of code
• 9 McCabe index (conditional complexity)

static int dw_i3c_master_daa(struct i3c_master_controller *m)
{
	struct dw_i3c_master *master = to_dw_i3c_master(m);
	struct dw_i3c_xfer *xfer;
	struct dw_i3c_cmd *cmd;
	u32 olddevs, newdevs;
	u8 p, last_addr = 0;
	int ret, pos;

	olddevs = ~(master->free_pos);

	/* Prepare DAT before launching DAA. */
	for (pos = 0; pos < master->maxdevs; pos++) {
		if (olddevs & BIT(pos))
			continue;

		ret = i3c_master_get_free_addr(m, last_addr + 1);
		if (ret < 0)
			return -ENOSPC;

		master->addrs[pos] = ret;
		p = even_parity(ret);
		last_addr = ret;
		ret |= (p << 7);

		writel(DEV_ADDR_TABLE_DYNAMIC_ADDR(ret),
		       master->regs +
		       DEV_ADDR_TABLE_LOC(master->datstartaddr, pos));
	}

	xfer = dw_i3c_master_alloc_xfer(master, 1);
	if (!xfer)
		return -ENOMEM;

	pos = dw_i3c_master_get_free_pos(master);
	if (pos < 0) {
		dw_i3c_master_free_xfer(xfer);
		return pos;
	}
	cmd = &xfer->cmds[0];
	cmd->cmd_hi = 0x1;
	cmd->cmd_lo = COMMAND_PORT_DEV_COUNT(master->maxdevs - pos) |
		      COMMAND_PORT_DEV_INDEX(pos) |
		      COMMAND_PORT_CMD(I3C_CCC_ENTDAA) |
		      COMMAND_PORT_ADDR_ASSGN_CMD |
		      COMMAND_PORT_TOC |
		      COMMAND_PORT_ROC;

	dw_i3c_master_enqueue_xfer(master, xfer);
	if (!wait_for_completion_timeout(&xfer->comp, XFER_TIMEOUT))
		dw_i3c_master_dequeue_xfer(master, xfer);

	newdevs = GENMASK(master->maxdevs - cmd->rx_len - 1, 0);
	newdevs &= ~olddevs;

	for (pos = 0; pos < master->maxdevs; pos++) {
		if (newdevs & BIT(pos))
			i3c_master_add_i3c_dev_locked(m, master->addrs[pos]);
	}

	dw_i3c_master_free_xfer(xfer);

	return 0;
}