diff options
Diffstat (limited to 'drivers/dma/bcm2835-dma.c')
| -rw-r--r-- | drivers/dma/bcm2835-dma.c | 27 |
1 files changed, 8 insertions, 19 deletions
diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c index ae10f5614f95..ec8a291d62ba 100644 --- a/drivers/dma/bcm2835-dma.c +++ b/drivers/dma/bcm2835-dma.c @@ -2,9 +2,6 @@ /* * BCM2835 DMA engine support * - * This driver only supports cyclic DMA transfers - * as needed for the I2S module. - * * Author: Florian Meier <florian.meier@koalo.de> * Copyright 2013 * @@ -42,7 +39,6 @@ struct bcm2835_dmadev { struct dma_device ddev; - spinlock_t lock; void __iomem *base; struct device_dma_parameters dma_parms; }; @@ -64,7 +60,6 @@ struct bcm2835_cb_entry { struct bcm2835_chan { struct virt_dma_chan vc; - struct list_head node; struct dma_slave_config cfg; unsigned int dreq; @@ -312,8 +307,7 @@ static struct bcm2835_desc *bcm2835_dma_create_cb_chain( return NULL; /* allocate and setup the descriptor. */ - d = kzalloc(sizeof(*d) + frames * sizeof(struct bcm2835_cb_entry), - gfp); + d = kzalloc(struct_size(d, cb_list, frames), gfp); if (!d) return NULL; @@ -406,7 +400,7 @@ static void bcm2835_dma_fill_cb_chain_with_sg( } } -static int bcm2835_dma_abort(struct bcm2835_chan *c) +static void bcm2835_dma_abort(struct bcm2835_chan *c) { void __iomem *chan_base = c->chan_base; long int timeout = 10000; @@ -416,7 +410,7 @@ static int bcm2835_dma_abort(struct bcm2835_chan *c) * (The ACTIVE flag in the CS register is not a reliable indicator.) */ if (!readl(chan_base + BCM2835_DMA_ADDR)) - return 0; + return; /* Write 0 to the active bit - Pause the DMA */ writel(0, chan_base + BCM2835_DMA_CS); @@ -432,7 +426,6 @@ static int bcm2835_dma_abort(struct bcm2835_chan *c) "failed to complete outstanding writes\n"); writel(BCM2835_DMA_RESET, chan_base + BCM2835_DMA_CS); - return 0; } static void bcm2835_dma_start_desc(struct bcm2835_chan *c) @@ -504,8 +497,12 @@ static int bcm2835_dma_alloc_chan_resources(struct dma_chan *chan) dev_dbg(dev, "Allocating DMA channel %d\n", c->ch); + /* + * Control blocks are 256 bit in length and must start at a 256 bit + * (32 byte) aligned address (BCM2835 ARM Peripherals, sec. 4.2.1.1). + */ c->cb_pool = dma_pool_create(dev_name(dev), dev, - sizeof(struct bcm2835_dma_cb), 0, 0); + sizeof(struct bcm2835_dma_cb), 32, 0); if (!c->cb_pool) { dev_err(dev, "unable to allocate descriptor pool\n"); return -ENOMEM; @@ -774,17 +771,11 @@ static int bcm2835_dma_slave_config(struct dma_chan *chan, static int bcm2835_dma_terminate_all(struct dma_chan *chan) { struct bcm2835_chan *c = to_bcm2835_dma_chan(chan); - struct bcm2835_dmadev *d = to_bcm2835_dma_dev(c->vc.chan.device); unsigned long flags; LIST_HEAD(head); spin_lock_irqsave(&c->vc.lock, flags); - /* Prevent this channel being scheduled */ - spin_lock(&d->lock); - list_del_init(&c->node); - spin_unlock(&d->lock); - /* stop DMA activity */ if (c->desc) { vchan_terminate_vdesc(&c->desc->vd); @@ -817,7 +808,6 @@ static int bcm2835_dma_chan_init(struct bcm2835_dmadev *d, int chan_id, c->vc.desc_free = bcm2835_dma_desc_free; vchan_init(&c->vc, &d->ddev); - INIT_LIST_HEAD(&c->node); c->chan_base = BCM2835_DMA_CHANIO(d->base, chan_id); c->ch = chan_id; @@ -920,7 +910,6 @@ static int bcm2835_dma_probe(struct platform_device *pdev) od->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; od->ddev.dev = &pdev->dev; INIT_LIST_HEAD(&od->ddev.channels); - spin_lock_init(&od->lock); platform_set_drvdata(pdev, od); |