diff options
| -rw-r--r-- | drivers/dma/amba-pl08x.c | 79 |
1 files changed, 32 insertions, 47 deletions
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c index 54e3eb0..e04ca0b 100644 --- a/drivers/dma/amba-pl08x.c +++ b/drivers/dma/amba-pl08x.c @@ -168,7 +168,6 @@ struct pl08x_sg { * @tx: async tx descriptor * @node: node for txd list for channels * @dsg_list: list of children sg's - * @direction: direction of transfer * @llis_bus: DMA memory address (physical) start for the LLIs * @llis_va: virtual memory address start for the LLIs * @cctl: control reg values for current txd @@ -178,7 +177,6 @@ struct pl08x_txd { struct dma_async_tx_descriptor tx; struct list_head node; struct list_head dsg_list; - enum dma_transfer_direction direction; dma_addr_t llis_bus; struct pl08x_lli *llis_va; /* Default cctl value for LLIs */ @@ -997,6 +995,7 @@ static void pl08x_free_txd_list(struct pl08x_driver_data *pl08x, if (!list_empty(&plchan->pend_list)) { list_for_each_entry_safe(txdi, next, &plchan->pend_list, node) { + pl08x_release_mux(plchan); list_del(&txdi->node); pl08x_free_txd(pl08x, txdi); } @@ -1018,12 +1017,10 @@ static void pl08x_free_chan_resources(struct dma_chan *chan) /* * This should be called with the channel plchan->lock held */ -static int prep_phy_channel(struct pl08x_dma_chan *plchan, - struct pl08x_txd *txd) +static int prep_phy_channel(struct pl08x_dma_chan *plchan) { struct pl08x_driver_data *pl08x = plchan->host; struct pl08x_phy_chan *ch; - int ret; /* Check if we already have a channel */ if (plchan->phychan) { @@ -1038,36 +1035,11 @@ static int prep_phy_channel(struct pl08x_dma_chan *plchan, return -EBUSY; } - /* - * OK we have a physical channel: for memcpy() this is all we - * need, but for slaves the physical signals may be muxed! - * Can the platform allow us to use this channel? - */ - if (plchan->slave) { - ret = pl08x_request_mux(plchan); - if (ret < 0) { - dev_dbg(&pl08x->adev->dev, - "unable to use physical channel %d for transfer on %s due to platform restrictions\n", - ch->id, plchan->name); - /* Release physical channel & return */ - pl08x_put_phy_channel(pl08x, ch); - return -EBUSY; - } - } - plchan->phychan = ch; - dev_dbg(&pl08x->adev->dev, "allocated physical channel %d and signal %d for xfer on %s\n", - ch->id, - plchan->signal, - plchan->name); + dev_dbg(&pl08x->adev->dev, "allocated physical channel %d for xfer on %s\n", + ch->id, plchan->name); got_channel: - /* Assign the flow control signal to this channel */ - if (txd->direction == DMA_MEM_TO_DEV) - txd->ccfg |= plchan->signal << PL080_CONFIG_DST_SEL_SHIFT; - else if (txd->direction == DMA_DEV_TO_MEM) - txd->ccfg |= plchan->signal << PL080_CONFIG_SRC_SEL_SHIFT; - plchan->phychan_hold++; return 0; @@ -1077,7 +1049,6 @@ static void release_phy_channel(struct pl08x_dma_chan *plchan) { struct pl08x_driver_data *pl08x = plchan->host; - pl08x_release_mux(plchan); pl08x_put_phy_channel(pl08x, plchan->phychan); plchan->phychan = NULL; } @@ -1340,19 +1311,12 @@ static int pl08x_prep_channel_resources(struct pl08x_dma_chan *plchan, * See if we already have a physical channel allocated, * else this is the time to try to get one. */ - ret = prep_phy_channel(plchan, txd); + ret = prep_phy_channel(plchan); if (ret) { /* * No physical channel was available. * * memcpy transfers can be sorted out at submission time. - * - * Slave transfers may have been denied due to platform - * channel muxing restrictions. Since there is no guarantee - * that this will ever be resolved, and the signal must be - * acquired AFTER acquiring the physical channel, we will let - * them be NACK:ed with -EBUSY here. The drivers can retry - * the prep() call if they are eager on doing this using DMA. */ if (plchan->slave) { pl08x_free_txd_list(pl08x, plchan); @@ -1423,7 +1387,6 @@ static struct dma_async_tx_descriptor *pl08x_prep_dma_memcpy( } list_add_tail(&dsg->node, &txd->dsg_list); - txd->direction = DMA_MEM_TO_MEM; dsg->src_addr = src; dsg->dst_addr = dest; dsg->len = len; @@ -1477,8 +1440,6 @@ static struct dma_async_tx_descriptor *pl08x_prep_slave_sg( * will take precedence since this may configure the * channel target address dynamically at runtime. */ - txd->direction = direction; - if (direction == DMA_MEM_TO_DEV) { cctl = PL080_CONTROL_SRC_INCR; slave_addr = plchan->cfg.dst_addr; @@ -1519,9 +1480,28 @@ static struct dma_async_tx_descriptor *pl08x_prep_slave_sg( txd->ccfg |= tmp << PL080_CONFIG_FLOW_CONTROL_SHIFT; + ret = pl08x_request_mux(plchan); + if (ret < 0) { + pl08x_free_txd(pl08x, txd); + dev_dbg(&pl08x->adev->dev, + "unable to mux for transfer on %s due to platform restrictions\n", + plchan->name); + return NULL; + } + + dev_dbg(&pl08x->adev->dev, "allocated DMA request signal %d for xfer on %s\n", + plchan->signal, plchan->name); + + /* Assign the flow control signal to this channel */ + if (direction == DMA_MEM_TO_DEV) + txd->ccfg |= plchan->signal << PL080_CONFIG_DST_SEL_SHIFT; + else + txd->ccfg |= plchan->signal << PL080_CONFIG_SRC_SEL_SHIFT; + for_each_sg(sgl, sg, sg_len, tmp) { dsg = kzalloc(sizeof(struct pl08x_sg), GFP_NOWAIT); if (!dsg) { + pl08x_release_mux(plchan); pl08x_free_txd(pl08x, txd); dev_err(&pl08x->adev->dev, "%s no mem for pl080 sg\n", __func__); @@ -1586,6 +1566,8 @@ static int pl08x_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, } /* Dequeue jobs and free LLIs */ if (plchan->at) { + /* Killing this one off, release its mux */ + pl08x_release_mux(plchan); pl08x_free_txd(pl08x, plchan->at); plchan->at = NULL; } @@ -1702,7 +1684,6 @@ static void pl08x_tasklet(unsigned long data) /* * No more jobs, so free up the physical channel - * Free any allocated signal on slave transfers too */ release_phy_channel(plchan); plchan->state = PL08X_CHAN_IDLE; @@ -1720,8 +1701,7 @@ static void pl08x_tasklet(unsigned long data) int ret; /* This should REALLY not fail now */ - ret = prep_phy_channel(waiting, - waiting->waiting); + ret = prep_phy_channel(waiting); BUG_ON(ret); waiting->phychan_hold--; waiting->state = PL08X_CHAN_RUNNING; @@ -1794,6 +1774,11 @@ static irqreturn_t pl08x_irq(int irq, void *dev) tx = plchan->at; if (tx) { plchan->at = NULL; + /* + * This descriptor is done, release its mux + * reservation. + */ + pl08x_release_mux(plchan); dma_cookie_complete(&tx->tx); list_add_tail(&tx->node, &plchan->done_list); } |
