Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[uclinux-h8/linux.git] / drivers / dma / bcm2835-dma.c

diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c
index ae10f56..ec8a291 100644 (file)
--- 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);