diff options
| -rw-r--r-- | drivers/dma/mmp_pdma.c | 112 |
1 files changed, 111 insertions, 1 deletions
diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c index 3676fde..f0e6d7d 100644 --- a/drivers/dma/mmp_pdma.c +++ b/drivers/dma/mmp_pdma.c @@ -98,6 +98,9 @@ struct mmp_pdma_chan { struct mmp_pdma_phy *phy; enum dma_transfer_direction dir; + struct mmp_pdma_desc_sw *cyclic_first; /* first desc_sw if channel + * is in cyclic mode */ + /* channel's basic info */ struct tasklet_struct tasklet; u32 dcmd; @@ -500,6 +503,8 @@ mmp_pdma_prep_memcpy(struct dma_chan *dchan, new->desc.ddadr = DDADR_STOP; new->desc.dcmd |= DCMD_ENDIRQEN; + chan->cyclic_first = NULL; + return &first->async_tx; fail: @@ -575,6 +580,94 @@ mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl, new->desc.ddadr = DDADR_STOP; new->desc.dcmd |= DCMD_ENDIRQEN; + chan->dir = dir; + chan->cyclic_first = NULL; + + return &first->async_tx; + +fail: + if (first) + mmp_pdma_free_desc_list(chan, &first->tx_list); + return NULL; +} + +static struct dma_async_tx_descriptor *mmp_pdma_prep_dma_cyclic( + struct dma_chan *dchan, dma_addr_t buf_addr, size_t len, + size_t period_len, enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct mmp_pdma_chan *chan; + struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new; + dma_addr_t dma_src, dma_dst; + + if (!dchan || !len || !period_len) + return NULL; + + /* the buffer length must be a multiple of period_len */ + if (len % period_len != 0) + return NULL; + + if (period_len > PDMA_MAX_DESC_BYTES) + return NULL; + + chan = to_mmp_pdma_chan(dchan); + + switch (direction) { + case DMA_MEM_TO_DEV: + dma_src = buf_addr; + dma_dst = chan->dev_addr; + break; + case DMA_DEV_TO_MEM: + dma_dst = buf_addr; + dma_src = chan->dev_addr; + break; + default: + dev_err(chan->dev, "Unsupported direction for cyclic DMA\n"); + return NULL; + } + + chan->dir = direction; + + do { + /* Allocate the link descriptor from DMA pool */ + new = mmp_pdma_alloc_descriptor(chan); + if (!new) { + dev_err(chan->dev, "no memory for desc\n"); + goto fail; + } + + new->desc.dcmd = chan->dcmd | DCMD_ENDIRQEN | + (DCMD_LENGTH & period_len); + new->desc.dsadr = dma_src; + new->desc.dtadr = dma_dst; + + if (!first) + first = new; + else + prev->desc.ddadr = new->async_tx.phys; + + new->async_tx.cookie = 0; + async_tx_ack(&new->async_tx); + + prev = new; + len -= period_len; + + if (chan->dir == DMA_MEM_TO_DEV) + dma_src += period_len; + else + dma_dst += period_len; + + /* Insert the link descriptor to the LD ring */ + list_add_tail(&new->node, &first->tx_list); + } while (len); + + first->async_tx.flags = flags; /* client is in control of this ack */ + first->async_tx.cookie = -EBUSY; + + /* make the cyclic link */ + new->desc.ddadr = first->async_tx.phys; + chan->cyclic_first = first; + return &first->async_tx; fail: @@ -681,8 +774,23 @@ static void dma_do_tasklet(unsigned long data) LIST_HEAD(chain_cleanup); unsigned long flags; - /* submit pending list; callback for each desc; free desc */ + if (chan->cyclic_first) { + dma_async_tx_callback cb = NULL; + void *cb_data = NULL; + spin_lock_irqsave(&chan->desc_lock, flags); + desc = chan->cyclic_first; + cb = desc->async_tx.callback; + cb_data = desc->async_tx.callback_param; + spin_unlock_irqrestore(&chan->desc_lock, flags); + + if (cb) + cb(cb_data); + + return; + } + + /* submit pending list; callback for each desc; free desc */ spin_lock_irqsave(&chan->desc_lock, flags); list_for_each_entry_safe(desc, _desc, &chan->chain_running, node) { @@ -876,12 +984,14 @@ static int mmp_pdma_probe(struct platform_device *op) dma_cap_set(DMA_SLAVE, pdev->device.cap_mask); dma_cap_set(DMA_MEMCPY, pdev->device.cap_mask); + dma_cap_set(DMA_CYCLIC, pdev->device.cap_mask); pdev->device.dev = &op->dev; pdev->device.device_alloc_chan_resources = mmp_pdma_alloc_chan_resources; pdev->device.device_free_chan_resources = mmp_pdma_free_chan_resources; pdev->device.device_tx_status = mmp_pdma_tx_status; pdev->device.device_prep_dma_memcpy = mmp_pdma_prep_memcpy; pdev->device.device_prep_slave_sg = mmp_pdma_prep_slave_sg; + pdev->device.device_prep_dma_cyclic = mmp_pdma_prep_dma_cyclic; pdev->device.device_issue_pending = mmp_pdma_issue_pending; pdev->device.device_control = mmp_pdma_control; pdev->device.copy_align = PDMA_ALIGNMENT; |