[PATCH v1] fsldma: Delete DMA_INTERRUPT capability

From: Vishnu Suresh
Date: Mon Dec 14 2009 - 08:31:01 EST


The DMA_INTERRUPT is a NULL transfer, triggering a
Programming Error. Though this Error is handled in
the driver with the fix given in "fsldma: Fix the DMA
halt when using DMA_INTERRUPT async_tx transfer."
<f79abb627f033c85a6088231f20c85bc4a9bd757>,
the RAID5 operation, which initiated the transaction
via Async_tx, hangs.

Hence, this patch removes the DMA_INTERRUPT capability
and the associated code from the driver.

Signed-off-by: Vishnu Suresh <Vishnu@xxxxxxxxxxxxx>
---
Changes with respect to v0
o. The functionality is removed instead of disabling as
per comments
o. Rebased to linux-next as of 20091214

drivers/dma/fsldma.c | 31 -------------------------------
1 files changed, 0 insertions(+), 31 deletions(-)

diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index 296f9e7..272097a 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -449,35 +449,6 @@ static void fsl_dma_free_chan_resources(struct dma_chan *chan)
fsl_chan->desc_pool = NULL;
}

-static struct dma_async_tx_descriptor *
-fsl_dma_prep_interrupt(struct dma_chan *chan, unsigned long flags)
-{
- struct fsl_dma_chan *fsl_chan;
- struct fsl_desc_sw *new;
-
- if (!chan)
- return NULL;
-
- fsl_chan = to_fsl_chan(chan);
-
- new = fsl_dma_alloc_descriptor(fsl_chan);
- if (!new) {
- dev_err(fsl_chan->dev, "No free memory for link descriptor\n");
- return NULL;
- }
-
- new->async_tx.cookie = -EBUSY;
- new->async_tx.flags = flags;
-
- /* Insert the link descriptor to the LD ring */
- list_add_tail(&new->node, &new->tx_list);
-
- /* Set End-of-link to the last link descriptor of new list*/
- set_ld_eol(fsl_chan, new);
-
- return &new->async_tx;
-}
-
static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
size_t len, unsigned long flags)
@@ -1200,11 +1171,9 @@ static int __devinit of_fsl_dma_probe(struct of_device *dev,
- fdev->reg.start + 1);

dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
- dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask);
dma_cap_set(DMA_SLAVE, fdev->common.cap_mask);
fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources;
fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources;
- fdev->common.device_prep_dma_interrupt = fsl_dma_prep_interrupt;
fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy;
fdev->common.device_is_tx_complete = fsl_dma_is_complete;
fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
--
1.6.4.2

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