static int dw_i3c_master_i2c_xfers()

in master/dw-i3c-master.c [970:1033]

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

static int dw_i3c_master_i2c_xfers(struct i2c_dev_desc *dev,
				   const struct i2c_msg *i2c_xfers,
				   int i2c_nxfers)
{
	struct dw_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
	struct i3c_master_controller *m = i2c_dev_get_master(dev);
	struct dw_i3c_master *master = to_dw_i3c_master(m);
	unsigned int nrxwords = 0, ntxwords = 0;
	struct dw_i3c_xfer *xfer;
	int i, ret = 0;

	if (!i2c_nxfers)
		return 0;

	if (i2c_nxfers > master->caps.cmdfifodepth)
		return -ENOTSUPP;

	for (i = 0; i < i2c_nxfers; i++) {
		if (i2c_xfers[i].flags & I2C_M_RD)
			nrxwords += DIV_ROUND_UP(i2c_xfers[i].len, 4);
		else
			ntxwords += DIV_ROUND_UP(i2c_xfers[i].len, 4);
	}

	if (ntxwords > master->caps.datafifodepth ||
	    nrxwords > master->caps.datafifodepth)
		return -ENOTSUPP;

	xfer = dw_i3c_master_alloc_xfer(master, i2c_nxfers);
	if (!xfer)
		return -ENOMEM;

	for (i = 0; i < i2c_nxfers; i++) {
		struct dw_i3c_cmd *cmd = &xfer->cmds[i];

		cmd->cmd_hi = COMMAND_PORT_ARG_DATA_LEN(i2c_xfers[i].len) |
			COMMAND_PORT_TRANSFER_ARG;

		cmd->cmd_lo = COMMAND_PORT_TID(i) |
			      COMMAND_PORT_DEV_INDEX(data->index) |
			      COMMAND_PORT_ROC;

		if (i2c_xfers[i].flags & I2C_M_RD) {
			cmd->cmd_lo |= COMMAND_PORT_READ_TRANSFER;
			cmd->rx_buf = i2c_xfers[i].buf;
			cmd->rx_len = i2c_xfers[i].len;
		} else {
			cmd->tx_buf = i2c_xfers[i].buf;
			cmd->tx_len = i2c_xfers[i].len;
		}

		if (i == (i2c_nxfers - 1))
			cmd->cmd_lo |= COMMAND_PORT_TOC;
	}

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

	ret = xfer->ret;
	dw_i3c_master_free_xfer(xfer);

	return ret;
}