[PATCH] DMA: mv_xor: Add a device_control function
Andrew Lunn
andrew at lunn.ch
Sat Nov 17 12:15:01 EST 2012
The dmatest module for DMA engines calls
device_control(dtc->chan, DMA_TERMINATE_ALL, 0);
after completing the tests. The documentation in
include/linux/dmaengine.h suggests this function is optional and
dma_async_device_register() also does not BUG_ON() when not passed a
function. However, dmatest is not the only code in the kernel
unconditionally calling device_control. So add an implementation
indicating all operations are not implemented.
Signed-off-by: Andrew Lunn <andrew at lunn.ch>
---
This patch applies on top of Thomas Petazzoni big code refactor.
drivers/dma/mv_xor.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index d645d43..c063aee 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -658,8 +658,6 @@ mv_xor_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
dev_dbg(mv_chan_to_devp(mv_chan),
"%s dest: %x src %x len: %u flags: %ld\n",
__func__, dest, src, len, flags);
- if (unlikely(len < MV_XOR_MIN_BYTE_COUNT))
- return NULL;
BUG_ON(len > MV_XOR_MAX_BYTE_COUNT);
@@ -697,8 +695,6 @@ mv_xor_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
dev_dbg(mv_chan_to_devp(mv_chan),
"%s dest: %x len: %u flags: %ld\n",
__func__, dest, len, flags);
- if (unlikely(len < MV_XOR_MIN_BYTE_COUNT))
- return NULL;
BUG_ON(len > MV_XOR_MAX_BYTE_COUNT);
@@ -731,9 +727,6 @@ mv_xor_prep_dma_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
struct mv_xor_desc_slot *sw_desc, *grp_start;
int slot_cnt;
- if (unlikely(len < MV_XOR_MIN_BYTE_COUNT))
- return NULL;
-
BUG_ON(len > MV_XOR_MAX_BYTE_COUNT);
dev_dbg(mv_chan_to_devp(mv_chan),
@@ -1089,6 +1082,14 @@ static int __devexit mv_xor_channel_remove(struct mv_xor_chan *mv_chan)
return 0;
}
+/* This driver does not implement any of the optional DMA operations. */
+static int
+mv_xor_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
+ unsigned long arg)
+{
+ return -ENOSYS;
+}
+
static struct mv_xor_chan * __devinit
mv_xor_channel_add(struct mv_xor_device *xordev,
struct platform_device *pdev,
@@ -1129,6 +1130,7 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
dma_dev->device_free_chan_resources = mv_xor_free_chan_resources;
dma_dev->device_tx_status = mv_xor_status;
dma_dev->device_issue_pending = mv_xor_issue_pending;
+ dma_dev->device_control = mv_xor_control;
dma_dev->dev = &pdev->dev;
/* set prep routines based on capability */
--
1.7.10.4
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