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7#ifndef VIRT_DMA_H
8#define VIRT_DMA_H
9
10#include <linux/dmaengine.h>
11#include <linux/interrupt.h>
12
13#include "dmaengine.h"
14
15struct virt_dma_desc {
16 struct dma_async_tx_descriptor tx;
17 struct dmaengine_result tx_result;
18
19 struct list_head node;
20};
21
22struct virt_dma_chan {
23 struct dma_chan chan;
24 struct tasklet_struct task;
25 void (*desc_free)(struct virt_dma_desc *);
26
27 spinlock_t lock;
28
29
30 struct list_head desc_allocated;
31 struct list_head desc_submitted;
32 struct list_head desc_issued;
33 struct list_head desc_completed;
34 struct list_head desc_terminated;
35
36 struct virt_dma_desc *cyclic;
37};
38
39static inline struct virt_dma_chan *to_virt_chan(struct dma_chan *chan)
40{
41 return container_of(chan, struct virt_dma_chan, chan);
42}
43
44void vchan_dma_desc_free_list(struct virt_dma_chan *vc, struct list_head *head);
45void vchan_init(struct virt_dma_chan *vc, struct dma_device *dmadev);
46struct virt_dma_desc *vchan_find_desc(struct virt_dma_chan *, dma_cookie_t);
47extern dma_cookie_t vchan_tx_submit(struct dma_async_tx_descriptor *);
48extern int vchan_tx_desc_free(struct dma_async_tx_descriptor *);
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55
56static inline struct dma_async_tx_descriptor *vchan_tx_prep(struct virt_dma_chan *vc,
57 struct virt_dma_desc *vd, unsigned long tx_flags)
58{
59 unsigned long flags;
60
61 dma_async_tx_descriptor_init(&vd->tx, &vc->chan);
62 vd->tx.flags = tx_flags;
63 vd->tx.tx_submit = vchan_tx_submit;
64 vd->tx.desc_free = vchan_tx_desc_free;
65
66 vd->tx_result.result = DMA_TRANS_NOERROR;
67 vd->tx_result.residue = 0;
68
69 spin_lock_irqsave(&vc->lock, flags);
70 list_add_tail(&vd->node, &vc->desc_allocated);
71 spin_unlock_irqrestore(&vc->lock, flags);
72
73 return &vd->tx;
74}
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81
82static inline bool vchan_issue_pending(struct virt_dma_chan *vc)
83{
84 list_splice_tail_init(&vc->desc_submitted, &vc->desc_issued);
85 return !list_empty(&vc->desc_issued);
86}
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93
94static inline void vchan_cookie_complete(struct virt_dma_desc *vd)
95{
96 struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
97 dma_cookie_t cookie;
98
99 cookie = vd->tx.cookie;
100 dma_cookie_complete(&vd->tx);
101 dev_vdbg(vc->chan.device->dev, "txd %p[%x]: marked complete\n",
102 vd, cookie);
103 list_add_tail(&vd->node, &vc->desc_completed);
104
105 tasklet_schedule(&vc->task);
106}
107
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111
112static inline void vchan_vdesc_fini(struct virt_dma_desc *vd)
113{
114 struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
115
116 if (dmaengine_desc_test_reuse(&vd->tx)) {
117 unsigned long flags;
118
119 spin_lock_irqsave(&vc->lock, flags);
120 list_add(&vd->node, &vc->desc_allocated);
121 spin_unlock_irqrestore(&vc->lock, flags);
122 } else {
123 vc->desc_free(vd);
124 }
125}
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130
131static inline void vchan_cyclic_callback(struct virt_dma_desc *vd)
132{
133 struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
134
135 vc->cyclic = vd;
136 tasklet_schedule(&vc->task);
137}
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144
145static inline void vchan_terminate_vdesc(struct virt_dma_desc *vd)
146{
147 struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
148
149 list_add_tail(&vd->node, &vc->desc_terminated);
150
151 if (vc->cyclic == vd)
152 vc->cyclic = NULL;
153}
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161static inline struct virt_dma_desc *vchan_next_desc(struct virt_dma_chan *vc)
162{
163 return list_first_entry_or_null(&vc->desc_issued,
164 struct virt_dma_desc, node);
165}
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176
177static inline void vchan_get_all_descriptors(struct virt_dma_chan *vc,
178 struct list_head *head)
179{
180 list_splice_tail_init(&vc->desc_allocated, head);
181 list_splice_tail_init(&vc->desc_submitted, head);
182 list_splice_tail_init(&vc->desc_issued, head);
183 list_splice_tail_init(&vc->desc_completed, head);
184 list_splice_tail_init(&vc->desc_terminated, head);
185}
186
187static inline void vchan_free_chan_resources(struct virt_dma_chan *vc)
188{
189 struct virt_dma_desc *vd;
190 unsigned long flags;
191 LIST_HEAD(head);
192
193 spin_lock_irqsave(&vc->lock, flags);
194 vchan_get_all_descriptors(vc, &head);
195 list_for_each_entry(vd, &head, node)
196 dmaengine_desc_clear_reuse(&vd->tx);
197 spin_unlock_irqrestore(&vc->lock, flags);
198
199 vchan_dma_desc_free_list(vc, &head);
200}
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210
211static inline void vchan_synchronize(struct virt_dma_chan *vc)
212{
213 LIST_HEAD(head);
214 unsigned long flags;
215
216 tasklet_kill(&vc->task);
217
218 spin_lock_irqsave(&vc->lock, flags);
219
220 list_splice_tail_init(&vc->desc_terminated, &head);
221
222 spin_unlock_irqrestore(&vc->lock, flags);
223
224 vchan_dma_desc_free_list(vc, &head);
225}
226
227#endif
228