Root/
| 1 | /* |
| 2 | * Virtual DMA channel support for DMAengine |
| 3 | * |
| 4 | * Copyright (C) 2012 Russell King |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | #include <linux/device.h> |
| 11 | #include <linux/dmaengine.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/spinlock.h> |
| 14 | |
| 15 | #include "virt-dma.h" |
| 16 | |
| 17 | static struct virt_dma_desc *to_virt_desc(struct dma_async_tx_descriptor *tx) |
| 18 | { |
| 19 | return container_of(tx, struct virt_dma_desc, tx); |
| 20 | } |
| 21 | |
| 22 | dma_cookie_t vchan_tx_submit(struct dma_async_tx_descriptor *tx) |
| 23 | { |
| 24 | struct virt_dma_chan *vc = to_virt_chan(tx->chan); |
| 25 | struct virt_dma_desc *vd = to_virt_desc(tx); |
| 26 | unsigned long flags; |
| 27 | dma_cookie_t cookie; |
| 28 | |
| 29 | spin_lock_irqsave(&vc->lock, flags); |
| 30 | cookie = dma_cookie_assign(tx); |
| 31 | |
| 32 | list_add_tail(&vd->node, &vc->desc_submitted); |
| 33 | spin_unlock_irqrestore(&vc->lock, flags); |
| 34 | |
| 35 | dev_dbg(vc->chan.device->dev, "vchan %p: txd %p[%x]: submitted\n", |
| 36 | vc, vd, cookie); |
| 37 | |
| 38 | return cookie; |
| 39 | } |
| 40 | EXPORT_SYMBOL_GPL(vchan_tx_submit); |
| 41 | |
| 42 | struct virt_dma_desc *vchan_find_desc(struct virt_dma_chan *vc, |
| 43 | dma_cookie_t cookie) |
| 44 | { |
| 45 | struct virt_dma_desc *vd; |
| 46 | |
| 47 | list_for_each_entry(vd, &vc->desc_issued, node) |
| 48 | if (vd->tx.cookie == cookie) |
| 49 | return vd; |
| 50 | |
| 51 | return NULL; |
| 52 | } |
| 53 | EXPORT_SYMBOL_GPL(vchan_find_desc); |
| 54 | |
| 55 | /* |
| 56 | * This tasklet handles the completion of a DMA descriptor by |
| 57 | * calling its callback and freeing it. |
| 58 | */ |
| 59 | static void vchan_complete(unsigned long arg) |
| 60 | { |
| 61 | struct virt_dma_chan *vc = (struct virt_dma_chan *)arg; |
| 62 | struct virt_dma_desc *vd; |
| 63 | dma_async_tx_callback cb = NULL; |
| 64 | void *cb_data = NULL; |
| 65 | LIST_HEAD(head); |
| 66 | |
| 67 | spin_lock_irq(&vc->lock); |
| 68 | list_splice_tail_init(&vc->desc_completed, &head); |
| 69 | vd = vc->cyclic; |
| 70 | if (vd) { |
| 71 | vc->cyclic = NULL; |
| 72 | cb = vd->tx.callback; |
| 73 | cb_data = vd->tx.callback_param; |
| 74 | } |
| 75 | spin_unlock_irq(&vc->lock); |
| 76 | |
| 77 | if (cb) |
| 78 | cb(cb_data); |
| 79 | |
| 80 | while (!list_empty(&head)) { |
| 81 | vd = list_first_entry(&head, struct virt_dma_desc, node); |
| 82 | cb = vd->tx.callback; |
| 83 | cb_data = vd->tx.callback_param; |
| 84 | |
| 85 | list_del(&vd->node); |
| 86 | |
| 87 | vc->desc_free(vd); |
| 88 | |
| 89 | if (cb) |
| 90 | cb(cb_data); |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | void vchan_dma_desc_free_list(struct virt_dma_chan *vc, struct list_head *head) |
| 95 | { |
| 96 | while (!list_empty(head)) { |
| 97 | struct virt_dma_desc *vd = list_first_entry(head, |
| 98 | struct virt_dma_desc, node); |
| 99 | list_del(&vd->node); |
| 100 | dev_dbg(vc->chan.device->dev, "txd %p: freeing\n", vd); |
| 101 | vc->desc_free(vd); |
| 102 | } |
| 103 | } |
| 104 | EXPORT_SYMBOL_GPL(vchan_dma_desc_free_list); |
| 105 | |
| 106 | void vchan_init(struct virt_dma_chan *vc, struct dma_device *dmadev) |
| 107 | { |
| 108 | dma_cookie_init(&vc->chan); |
| 109 | |
| 110 | spin_lock_init(&vc->lock); |
| 111 | INIT_LIST_HEAD(&vc->desc_submitted); |
| 112 | INIT_LIST_HEAD(&vc->desc_issued); |
| 113 | INIT_LIST_HEAD(&vc->desc_completed); |
| 114 | |
| 115 | tasklet_init(&vc->task, vchan_complete, (unsigned long)vc); |
| 116 | |
| 117 | vc->chan.device = dmadev; |
| 118 | list_add_tail(&vc->chan.device_node, &dmadev->channels); |
| 119 | } |
| 120 | EXPORT_SYMBOL_GPL(vchan_init); |
| 121 | |
| 122 | MODULE_AUTHOR("Russell King"); |
| 123 | MODULE_LICENSE("GPL"); |
| 124 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9
