drivers/crypto/qce/dma.c

   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
  11 int 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;
  35 error_nomem:
  36         dma_release_channel(dma->rxchan);
  37 error_rx:
  38         dma_release_channel(dma->txchan);
  39         return ret;
  40 }
  41
  42 void 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
  49 struct scatterlist *
  50 qce_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
  77 static 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
  99 int 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
 117 void 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
 123 int 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 }