From 0b94c57717054811dd836d582585d3fb4856b43f Mon Sep 17 00:00:00 2001 From: Padmavathi Venna Date: Tue, 5 Mar 2013 14:55:31 +0530 Subject: DMA: PL330: Add check if device tree compatible This patch register the dma controller with generic dma helpers only in DT case. This also adds some extra error handling in the driver. Signed-off-by: Padmavathi Venna Reported-by: Sachin Kamat Signed-off-by: Vinod Koul --- drivers/dma/pl330.c | 38 +++++++++++++++++++++++++++----------- 1 file changed, 27 insertions(+), 11 deletions(-) (limited to 'drivers/dma') diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 718153122759..5dbc5946c4c3 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -2882,7 +2882,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) { struct dma_pl330_platdata *pdat; struct dma_pl330_dmac *pdmac; - struct dma_pl330_chan *pch; + struct dma_pl330_chan *pch, *_p; struct pl330_info *pi; struct dma_device *pd; struct resource *res; @@ -2984,7 +2984,16 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) ret = dma_async_device_register(pd); if (ret) { dev_err(&adev->dev, "unable to register DMAC\n"); - goto probe_err2; + goto probe_err3; + } + + if (adev->dev.of_node) { + ret = of_dma_controller_register(adev->dev.of_node, + of_dma_pl330_xlate, pdmac); + if (ret) { + dev_err(&adev->dev, + "unable to register DMA to the generic DT DMA helpers\n"); + } } dev_info(&adev->dev, @@ -2995,16 +3004,21 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) pi->pcfg.data_bus_width / 8, pi->pcfg.num_chan, pi->pcfg.num_peri, pi->pcfg.num_events); - ret = of_dma_controller_register(adev->dev.of_node, - of_dma_pl330_xlate, pdmac); - if (ret) { - dev_err(&adev->dev, - "unable to register DMA to the generic DT DMA helpers\n"); - goto probe_err2; - } - return 0; +probe_err3: + amba_set_drvdata(adev, NULL); + /* Idle the DMAC */ + list_for_each_entry_safe(pch, _p, &pdmac->ddma.channels, + chan.device_node) { + + /* Remove the channel */ + list_del(&pch->chan.device_node); + + /* Flush the channel */ + pl330_control(&pch->chan, DMA_TERMINATE_ALL, 0); + pl330_free_chan_resources(&pch->chan); + } probe_err2: pl330_del(pi); probe_err1: @@ -3023,8 +3037,10 @@ static int pl330_remove(struct amba_device *adev) if (!pdmac) return 0; - of_dma_controller_free(adev->dev.of_node); + if (adev->dev.of_node) + of_dma_controller_free(adev->dev.of_node); + dma_async_device_unregister(&pdmac->ddma); amba_set_drvdata(adev, NULL); /* Idle the DMAC */ -- cgit v1.2.1 From 765024697807ad1e1cac332aa891253ca4a339da Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Tue, 9 Apr 2013 16:33:06 +0200 Subject: dmaengine: omap-dma: Start DMA without delay for cyclic channels cyclic DMA is only used by audio which needs DMA to be started without a delay. If the DMA for audio is started using the tasklet we experience random channel switch (to be more precise: channel shift). Reported-by: Peter Meerwald CC: stable@vger.kernel.org # v3.7+ Signed-off-by: Peter Ujfalusi Acked-by: Santosh Shilimkar Acked-by: Russell King Signed-off-by: Vinod Koul --- drivers/dma/omap-dma.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'drivers/dma') diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index c4b4fd2acc42..08b43bf37158 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -276,12 +276,20 @@ static void omap_dma_issue_pending(struct dma_chan *chan) spin_lock_irqsave(&c->vc.lock, flags); if (vchan_issue_pending(&c->vc) && !c->desc) { - struct omap_dmadev *d = to_omap_dma_dev(chan->device); - spin_lock(&d->lock); - if (list_empty(&c->node)) - list_add_tail(&c->node, &d->pending); - spin_unlock(&d->lock); - tasklet_schedule(&d->task); + /* + * c->cyclic is used only by audio and in this case the DMA need + * to be started without delay. + */ + if (!c->cyclic) { + struct omap_dmadev *d = to_omap_dma_dev(chan->device); + spin_lock(&d->lock); + if (list_empty(&c->node)) + list_add_tail(&c->node, &d->pending); + spin_unlock(&d->lock); + tasklet_schedule(&d->task); + } else { + omap_dma_start_desc(c); + } } spin_unlock_irqrestore(&c->vc.lock, flags); } -- cgit v1.2.1 From d202f05158442396033f416df376f8ece1f563df Mon Sep 17 00:00:00 2001 From: Ludovic Desroches Date: Thu, 18 Apr 2013 09:52:59 +0200 Subject: dmaengine: at_hdmac: fix race condition in atc_advance_work() The BUG_ON() directive is triggered probably due to a latency modification following inclusion of commit c10d73671ad3 ("softirq: reduce latencies"). This condition has not been met before 3.9-rc1 and doesn't trigger without this patch. We now make sure that DMA channel is idle before calling atc_complete_all() which makes the BUG_ON() "protection" useless. Signed-off-by: Ludovic Desroches Signed-off-by: Nicolas Ferre Acked-by: Vinod Koul Signed-off-by: Linus Torvalds --- drivers/dma/at_hdmac.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'drivers/dma') diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 6e13f262139a..88cfc61329d2 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -310,8 +310,6 @@ static void atc_complete_all(struct at_dma_chan *atchan) dev_vdbg(chan2dev(&atchan->chan_common), "complete all\n"); - BUG_ON(atc_chan_is_enabled(atchan)); - /* * Submit queued descriptors ASAP, i.e. before we go through * the completed ones. @@ -368,6 +366,9 @@ static void atc_advance_work(struct at_dma_chan *atchan) { dev_vdbg(chan2dev(&atchan->chan_common), "advance_work\n"); + if (atc_chan_is_enabled(atchan)) + return; + if (list_empty(&atchan->active_list) || list_is_singular(&atchan->active_list)) { atc_complete_all(atchan); @@ -1078,9 +1079,7 @@ static void atc_issue_pending(struct dma_chan *chan) return; spin_lock_irqsave(&atchan->lock, flags); - if (!atc_chan_is_enabled(atchan)) { - atc_advance_work(atchan); - } + atc_advance_work(atchan); spin_unlock_irqrestore(&atchan->lock, flags); } -- cgit v1.2.1