static int qcom_slim_ngd_tx_msg_post()

in qcom-ngd-ctrl.c [567:601]

• 30 lines of code
• 2 McCabe index (conditional complexity)

static int qcom_slim_ngd_tx_msg_post(struct qcom_slim_ngd_ctrl *ctrl,
				     void *buf, int len)
{
	struct qcom_slim_ngd_dma_desc *desc;
	unsigned long flags;
	int index, offset;

	spin_lock_irqsave(&ctrl->tx_buf_lock, flags);
	offset = buf - ctrl->tx_base;
	index = offset/SLIM_MSGQ_BUF_LEN;

	desc = &ctrl->txdesc[index];
	desc->phys = ctrl->tx_phys_base + offset;
	desc->base = ctrl->tx_base + offset;
	desc->ctrl = ctrl;
	len = (len + 3) & 0xfc;

	desc->desc = dmaengine_prep_slave_single(ctrl->dma_tx_channel,
						desc->phys, len,
						DMA_MEM_TO_DEV,
						DMA_PREP_INTERRUPT);
	if (!desc->desc) {
		dev_err(ctrl->dev, "unable to prepare channel\n");
		spin_unlock_irqrestore(&ctrl->tx_buf_lock, flags);
		return -EINVAL;
	}

	desc->desc->callback = qcom_slim_ngd_tx_msg_dma_cb;
	desc->desc->callback_param = desc;
	desc->desc->cookie = dmaengine_submit(desc->desc);
	dma_async_issue_pending(ctrl->dma_tx_channel);
	spin_unlock_irqrestore(&ctrl->tx_buf_lock, flags);

	return 0;
}