1/*
2 * Copyright (c) 2012-2014, The Linux Foundation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 and
6 * only version 2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11 * GNU General Public License for more details.
12 */
13
14#include <linux/dmaengine.h>
15#include <crypto/scatterwalk.h>
16
17#include "dma.h"
18
19int qce_dma_request(struct device *dev, struct qce_dma_data *dma)
20{
21	int ret;
22
23	dma->txchan = dma_request_slave_channel_reason(dev, "tx");
24	if (IS_ERR(dma->txchan))
25		return PTR_ERR(dma->txchan);
26
27	dma->rxchan = dma_request_slave_channel_reason(dev, "rx");
28	if (IS_ERR(dma->rxchan)) {
29		ret = PTR_ERR(dma->rxchan);
30		goto error_rx;
31	}
32
33	dma->result_buf = kmalloc(QCE_RESULT_BUF_SZ + QCE_IGNORE_BUF_SZ,
34				  GFP_KERNEL);
35	if (!dma->result_buf) {
36		ret = -ENOMEM;
37		goto error_nomem;
38	}
39
40	dma->ignore_buf = dma->result_buf + QCE_RESULT_BUF_SZ;
41
42	return 0;
43error_nomem:
44	dma_release_channel(dma->rxchan);
45error_rx:
46	dma_release_channel(dma->txchan);
47	return ret;
48}
49
50void qce_dma_release(struct qce_dma_data *dma)
51{
52	dma_release_channel(dma->txchan);
53	dma_release_channel(dma->rxchan);
54	kfree(dma->result_buf);
55}
56
57struct scatterlist *
58qce_sgtable_add(struct sg_table *sgt, struct scatterlist *new_sgl)
59{
60	struct scatterlist *sg = sgt->sgl, *sg_last = NULL;
61
62	while (sg) {
63		if (!sg_page(sg))
64			break;
65		sg = sg_next(sg);
66	}
67
68	if (!sg)
69		return ERR_PTR(-EINVAL);
70
71	while (new_sgl && sg) {
72		sg_set_page(sg, sg_page(new_sgl), new_sgl->length,
73			    new_sgl->offset);
74		sg_last = sg;
75		sg = sg_next(sg);
76		new_sgl = sg_next(new_sgl);
77	}
78
79	return sg_last;
80}
81
82static int qce_dma_prep_sg(struct dma_chan *chan, struct scatterlist *sg,
83			   int nents, unsigned long flags,
84			   enum dma_transfer_direction dir,
85			   dma_async_tx_callback cb, void *cb_param)
86{
87	struct dma_async_tx_descriptor *desc;
88	dma_cookie_t cookie;
89
90	if (!sg || !nents)
91		return -EINVAL;
92
93	desc = dmaengine_prep_slave_sg(chan, sg, nents, dir, flags);
94	if (!desc)
95		return -EINVAL;
96
97	desc->callback = cb;
98	desc->callback_param = cb_param;
99	cookie = dmaengine_submit(desc);
100
101	return dma_submit_error(cookie);
102}
103
104int qce_dma_prep_sgs(struct qce_dma_data *dma, struct scatterlist *rx_sg,
105		     int rx_nents, struct scatterlist *tx_sg, int tx_nents,
106		     dma_async_tx_callback cb, void *cb_param)
107{
108	struct dma_chan *rxchan = dma->rxchan;
109	struct dma_chan *txchan = dma->txchan;
110	unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
111	int ret;
112
113	ret = qce_dma_prep_sg(rxchan, rx_sg, rx_nents, flags, DMA_MEM_TO_DEV,
114			     NULL, NULL);
115	if (ret)
116		return ret;
117
118	return qce_dma_prep_sg(txchan, tx_sg, tx_nents, flags, DMA_DEV_TO_MEM,
119			       cb, cb_param);
120}
121
122void qce_dma_issue_pending(struct qce_dma_data *dma)
123{
124	dma_async_issue_pending(dma->rxchan);
125	dma_async_issue_pending(dma->txchan);
126}
127
128int qce_dma_terminate_all(struct qce_dma_data *dma)
129{
130	int ret;
131
132	ret = dmaengine_terminate_all(dma->rxchan);
133	return ret ?: dmaengine_terminate_all(dma->txchan);
134}
135