1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2012-2014, The Linux Foundation. All rights reserved.
  4 */
  5
  6#include <linux/dmaengine.h>
  7#include <crypto/scatterwalk.h>
  8
  9#include "dma.h"
 10
 11int qce_dma_request(struct device *dev, struct qce_dma_data *dma)
 12{
 13	int ret;
 14
 15	dma->txchan = dma_request_chan(dev, "tx");
 16	if (IS_ERR(dma->txchan))
 17		return PTR_ERR(dma->txchan);
 18
 19	dma->rxchan = dma_request_chan(dev, "rx");
 20	if (IS_ERR(dma->rxchan)) {
 21		ret = PTR_ERR(dma->rxchan);
 22		goto error_rx;
 23	}
 24
 25	dma->result_buf = kmalloc(QCE_RESULT_BUF_SZ + QCE_IGNORE_BUF_SZ,
 26				  GFP_KERNEL);
 27	if (!dma->result_buf) {
 28		ret = -ENOMEM;
 29		goto error_nomem;
 30	}
 31
 32	dma->ignore_buf = dma->result_buf + QCE_RESULT_BUF_SZ;
 33
 34	return 0;
 35error_nomem:
 36	dma_release_channel(dma->rxchan);
 37error_rx:
 38	dma_release_channel(dma->txchan);
 39	return ret;
 40}
 41
 42void qce_dma_release(struct qce_dma_data *dma)
 43{
 44	dma_release_channel(dma->txchan);
 45	dma_release_channel(dma->rxchan);
 46	kfree(dma->result_buf);
 47}
 48
 49struct scatterlist *
 50qce_sgtable_add(struct sg_table *sgt, struct scatterlist *new_sgl,
 51		unsigned int max_len)
 52{
 53	struct scatterlist *sg = sgt->sgl, *sg_last = NULL;
 54	unsigned int new_len;
 55
 56	while (sg) {
 57		if (!sg_page(sg))
 58			break;
 59		sg = sg_next(sg);
 60	}
 61
 62	if (!sg)
 63		return ERR_PTR(-EINVAL);
 64
 65	while (new_sgl && sg && max_len) {
 66		new_len = new_sgl->length > max_len ? max_len : new_sgl->length;
 67		sg_set_page(sg, sg_page(new_sgl), new_len, new_sgl->offset);
 68		sg_last = sg;
 69		sg = sg_next(sg);
 70		new_sgl = sg_next(new_sgl);
 71		max_len -= new_len;
 72	}
 73
 74	return sg_last;
 75}
 76
 77static int qce_dma_prep_sg(struct dma_chan *chan, struct scatterlist *sg,
 78			   int nents, unsigned long flags,
 79			   enum dma_transfer_direction dir,
 80			   dma_async_tx_callback cb, void *cb_param)
 81{
 82	struct dma_async_tx_descriptor *desc;
 83	dma_cookie_t cookie;
 84
 85	if (!sg || !nents)
 86		return -EINVAL;
 87
 88	desc = dmaengine_prep_slave_sg(chan, sg, nents, dir, flags);
 89	if (!desc)
 90		return -EINVAL;
 91
 92	desc->callback = cb;
 93	desc->callback_param = cb_param;
 94	cookie = dmaengine_submit(desc);
 95
 96	return dma_submit_error(cookie);
 97}
 98
 99int qce_dma_prep_sgs(struct qce_dma_data *dma, struct scatterlist *rx_sg,
100		     int rx_nents, struct scatterlist *tx_sg, int tx_nents,
101		     dma_async_tx_callback cb, void *cb_param)
102{
103	struct dma_chan *rxchan = dma->rxchan;
104	struct dma_chan *txchan = dma->txchan;
105	unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
106	int ret;
107
108	ret = qce_dma_prep_sg(rxchan, rx_sg, rx_nents, flags, DMA_MEM_TO_DEV,
109			     NULL, NULL);
110	if (ret)
111		return ret;
112
113	return qce_dma_prep_sg(txchan, tx_sg, tx_nents, flags, DMA_DEV_TO_MEM,
114			       cb, cb_param);
115}
116
117void qce_dma_issue_pending(struct qce_dma_data *dma)
118{
119	dma_async_issue_pending(dma->rxchan);
120	dma_async_issue_pending(dma->txchan);
121}
122
123int qce_dma_terminate_all(struct qce_dma_data *dma)
124{
125	int ret;
126
127	ret = dmaengine_terminate_all(dma->rxchan);
128	return ret ?: dmaengine_terminate_all(dma->txchan);
129}