This patch adds DMA_CYCLIC capability that is used for audio driver. DMA driver activated with it reuses the dma requests that were submitted through tx_submit().
Signed-off-by: Boojin Kim <[email protected]> Signed-off-by: Kukjin Kim <[email protected]> --- drivers/dma/pl330.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 111 insertions(+), 0 deletions(-) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 880f010..121c75a 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -69,6 +69,11 @@ struct dma_pl330_chan { * NULL if the channel is available to be acquired. */ void *pl330_chid; + + /* taks for cyclic capability */ + struct tasklet_struct *cyclic_task; + + bool cyclic; }; struct dma_pl330_dmac { @@ -184,6 +189,41 @@ static inline void fill_queue(struct dma_pl330_chan *pch) } } +static void pl330_tasklet_cyclic(unsigned long data) +{ + struct dma_pl330_chan *pch = (struct dma_pl330_chan *)data; + struct dma_pl330_desc *desc, *_dt; + unsigned long flags; + LIST_HEAD(list); + + spin_lock_irqsave(&pch->lock, flags); + + /* Pick up ripe tomatoes */ + list_for_each_entry_safe(desc, _dt, &pch->work_list, node) + if (desc->status == DONE) { + dma_async_tx_callback callback; + + list_move_tail(&desc->node, &pch->work_list); + pch->completed = desc->txd.cookie; + + desc->status = PREP; + + /* Try to submit a req imm. + next to the last completed cookie */ + fill_queue(pch); + + /* Make sure the PL330 Channel thread is active */ + pl330_chan_ctrl(pch->pl330_chid, PL330_OP_START); + + callback = desc->txd.callback; + if (callback) + callback(desc->txd.callback_param); + + } + + spin_unlock_irqrestore(&pch->lock, flags); +} + static void pl330_tasklet(unsigned long data) { struct dma_pl330_chan *pch = (struct dma_pl330_chan *)data; @@ -227,6 +267,9 @@ static void dma_pl330_rqcb(void *token, enum pl330_op_err err) spin_unlock_irqrestore(&pch->lock, flags); + if (pch->cyclic_task) + tasklet_schedule(pch->cyclic_task); + else tasklet_schedule(&pch->task); } @@ -316,6 +359,15 @@ static void pl330_free_chan_resources(struct dma_chan *chan) pl330_release_channel(pch->pl330_chid); pch->pl330_chid = NULL; + if (pch->cyclic) { + pch->cyclic = false; + list_splice_tail_init(&pch->work_list, &pch->dmac->desc_pool); + if (pch->cyclic_task) { + tasklet_kill(pch->cyclic_task); + pch->cyclic_task = NULL; + } + } + spin_unlock_irqrestore(&pch->lock, flags); } @@ -547,6 +599,63 @@ static inline int get_burst_len(struct dma_pl330_desc *desc, size_t len) return burst_len; } +static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic( + struct dma_chan *chan, dma_addr_t dma_addr, size_t len, + size_t period_len, enum dma_data_direction direction) +{ + struct dma_pl330_desc *desc; + struct dma_pl330_chan *pch = to_pchan(chan); + struct dma_pl330_peri *peri = chan->private; + dma_addr_t dst; + dma_addr_t src; + + pch = to_pchan(chan); + if (!pch) + return NULL; + + desc = pl330_get_desc(pch); + if (!desc) { + dev_err(pch->dmac->pif.dev, "%s:%d Unable to fetch desc\n", + __func__, __LINE__); + return NULL; + } + + switch (direction) { + case DMA_TO_DEVICE: + desc->rqcfg.src_inc = 1; + desc->rqcfg.dst_inc = 0; + src = dma_addr; + dst = peri->fifo_addr; + break; + case DMA_FROM_DEVICE: + desc->rqcfg.src_inc = 0; + desc->rqcfg.dst_inc = 1; + src = peri->fifo_addr; + dst = dma_addr; + break; + default: + dev_err(pch->dmac->pif.dev, "%s:%d Invalid dma direction\n", + __func__, __LINE__); + return NULL; + } + + desc->rqcfg.brst_size = peri->burst_sz; + desc->rqcfg.brst_len = 1; + + if (!pch->cyclic_task) { + pch->cyclic_task = + kmalloc(sizeof(struct tasklet_struct), GFP_KERNEL); + tasklet_init(pch->cyclic_task, + pl330_tasklet_cyclic, (unsigned int)pch); + } + + pch->cyclic = true; + + fill_px(&desc->px, dst, src, period_len); + + return &desc->txd; +} + static struct dma_async_tx_descriptor * pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst, dma_addr_t src, size_t len, unsigned long flags) @@ -780,6 +889,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) case MEMTODEV: case DEVTOMEM: dma_cap_set(DMA_SLAVE, pd->cap_mask); + dma_cap_set(DMA_CYCLIC, pd->cap_mask); break; default: dev_err(&adev->dev, "DEVTODEV Not Supported\n"); @@ -805,6 +915,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) pd->device_alloc_chan_resources = pl330_alloc_chan_resources; pd->device_free_chan_resources = pl330_free_chan_resources; pd->device_prep_dma_memcpy = pl330_prep_dma_memcpy; + pd->device_prep_dma_cyclic = pl330_prep_dma_cyclic; pd->device_tx_status = pl330_tx_status; pd->device_prep_slave_sg = pl330_prep_slave_sg; pd->device_control = pl330_control; -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
