static int sdw_bank_switch()

in stream.c [657:724]

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

static int sdw_bank_switch(struct sdw_bus *bus, int m_rt_count)
{
	int col_index, row_index;
	bool multi_link;
	struct sdw_msg *wr_msg;
	u8 *wbuf;
	int ret;
	u16 addr;

	wr_msg = kzalloc(sizeof(*wr_msg), GFP_KERNEL);
	if (!wr_msg)
		return -ENOMEM;

	bus->defer_msg.msg = wr_msg;

	wbuf = kzalloc(sizeof(*wbuf), GFP_KERNEL);
	if (!wbuf) {
		ret = -ENOMEM;
		goto error_1;
	}

	/* Get row and column index to program register */
	col_index = sdw_find_col_index(bus->params.col);
	row_index = sdw_find_row_index(bus->params.row);
	wbuf[0] = col_index | (row_index << 3);

	if (bus->params.next_bank)
		addr = SDW_SCP_FRAMECTRL_B1;
	else
		addr = SDW_SCP_FRAMECTRL_B0;

	sdw_fill_msg(wr_msg, NULL, addr, 1, SDW_BROADCAST_DEV_NUM,
		     SDW_MSG_FLAG_WRITE, wbuf);
	wr_msg->ssp_sync = true;

	/*
	 * Set the multi_link flag only when both the hardware supports
	 * and hardware-based sync is required
	 */
	multi_link = bus->multi_link && (m_rt_count >= bus->hw_sync_min_links);

	if (multi_link)
		ret = sdw_transfer_defer(bus, wr_msg, &bus->defer_msg);
	else
		ret = sdw_transfer(bus, wr_msg);

	if (ret < 0 && ret != -ENODATA) {
		dev_err(bus->dev, "Slave frame_ctrl reg write failed\n");
		goto error;
	}

	if (!multi_link) {
		kfree(wr_msg);
		kfree(wbuf);
		bus->defer_msg.msg = NULL;
		bus->params.curr_bank = !bus->params.curr_bank;
		bus->params.next_bank = !bus->params.next_bank;
	}

	return 0;

error:
	kfree(wbuf);
error_1:
	kfree(wr_msg);
	bus->defer_msg.msg = NULL;
	return ret;
}