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 19 int 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; 43 error_nomem: 44 dma_release_channel(dma->rxchan); 45 error_rx: 46 dma_release_channel(dma->txchan); 47 return ret; 48 } 49 50 void 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 57 int qce_mapsg(struct device *dev, struct scatterlist *sg, int nents, 58 enum dma_data_direction dir, bool chained) 59 { 60 int err; 61 62 if (chained) { 63 while (sg) { 64 err = dma_map_sg(dev, sg, 1, dir); 65 if (!err) 66 return -EFAULT; 67 sg = scatterwalk_sg_next(sg); 68 } 69 } else { 70 err = dma_map_sg(dev, sg, nents, dir); 71 if (!err) 72 return -EFAULT; 73 } 74 75 return nents; 76 } 77 78 void qce_unmapsg(struct device *dev, struct scatterlist *sg, int nents, 79 enum dma_data_direction dir, bool chained) 80 { 81 if (chained) 82 while (sg) { 83 dma_unmap_sg(dev, sg, 1, dir); 84 sg = scatterwalk_sg_next(sg); 85 } 86 else 87 dma_unmap_sg(dev, sg, nents, dir); 88 } 89 90 int qce_countsg(struct scatterlist *sglist, int nbytes, bool *chained) 91 { 92 struct scatterlist *sg = sglist; 93 int nents = 0; 94 95 if (chained) 96 *chained = false; 97 98 while (nbytes > 0 && sg) { 99 nents++; 100 nbytes -= sg->length; 101 if (!sg_is_last(sg) && (sg + 1)->length == 0 && chained) 102 *chained = true; 103 sg = scatterwalk_sg_next(sg); 104 } 105 106 return nents; 107 } 108 109 struct scatterlist * 110 qce_sgtable_add(struct sg_table *sgt, struct scatterlist *new_sgl) 111 { 112 struct scatterlist *sg = sgt->sgl, *sg_last = NULL; 113 114 while (sg) { 115 if (!sg_page(sg)) 116 break; 117 sg = sg_next(sg); 118 } 119 120 if (!sg) 121 return ERR_PTR(-EINVAL); 122 123 while (new_sgl && sg) { 124 sg_set_page(sg, sg_page(new_sgl), new_sgl->length, 125 new_sgl->offset); 126 sg_last = sg; 127 sg = sg_next(sg); 128 new_sgl = sg_next(new_sgl); 129 } 130 131 return sg_last; 132 } 133 134 static int qce_dma_prep_sg(struct dma_chan *chan, struct scatterlist *sg, 135 int nents, unsigned long flags, 136 enum dma_transfer_direction dir, 137 dma_async_tx_callback cb, void *cb_param) 138 { 139 struct dma_async_tx_descriptor *desc; 140 dma_cookie_t cookie; 141 142 if (!sg || !nents) 143 return -EINVAL; 144 145 desc = dmaengine_prep_slave_sg(chan, sg, nents, dir, flags); 146 if (!desc) 147 return -EINVAL; 148 149 desc->callback = cb; 150 desc->callback_param = cb_param; 151 cookie = dmaengine_submit(desc); 152 153 return dma_submit_error(cookie); 154 } 155 156 int qce_dma_prep_sgs(struct qce_dma_data *dma, struct scatterlist *rx_sg, 157 int rx_nents, struct scatterlist *tx_sg, int tx_nents, 158 dma_async_tx_callback cb, void *cb_param) 159 { 160 struct dma_chan *rxchan = dma->rxchan; 161 struct dma_chan *txchan = dma->txchan; 162 unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK; 163 int ret; 164 165 ret = qce_dma_prep_sg(rxchan, rx_sg, rx_nents, flags, DMA_MEM_TO_DEV, 166 NULL, NULL); 167 if (ret) 168 return ret; 169 170 return qce_dma_prep_sg(txchan, tx_sg, tx_nents, flags, DMA_DEV_TO_MEM, 171 cb, cb_param); 172 } 173 174 void qce_dma_issue_pending(struct qce_dma_data *dma) 175 { 176 dma_async_issue_pending(dma->rxchan); 177 dma_async_issue_pending(dma->txchan); 178 } 179 180 int qce_dma_terminate_all(struct qce_dma_data *dma) 181 { 182 int ret; 183 184 ret = dmaengine_terminate_all(dma->rxchan); 185 return ret ?: dmaengine_terminate_all(dma->txchan); 186 } 187