summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--drivers/dma/dmaengine.c9
-rw-r--r--drivers/dma/of-dma.c12
-rw-r--r--include/linux/dmaengine.h20
3 files changed, 34 insertions, 7 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index ca1400d66957..8c9f45fd55fc 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -482,7 +482,8 @@ int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
device = chan->device;
/* check if the channel supports slave transactions */
- if (!test_bit(DMA_SLAVE, device->cap_mask.bits))
+ if (!(test_bit(DMA_SLAVE, device->cap_mask.bits) ||
+ test_bit(DMA_CYCLIC, device->cap_mask.bits)))
return -ENXIO;
/*
@@ -865,12 +866,12 @@ static bool device_has_all_tx_types(struct dma_device *device)
return false;
#endif
- #if defined(CONFIG_ASYNC_MEMCPY) || defined(CONFIG_ASYNC_MEMCPY_MODULE)
+ #if IS_ENABLED(CONFIG_ASYNC_MEMCPY)
if (!dma_has_cap(DMA_MEMCPY, device->cap_mask))
return false;
#endif
- #if defined(CONFIG_ASYNC_XOR) || defined(CONFIG_ASYNC_XOR_MODULE)
+ #if IS_ENABLED(CONFIG_ASYNC_XOR)
if (!dma_has_cap(DMA_XOR, device->cap_mask))
return false;
@@ -880,7 +881,7 @@ static bool device_has_all_tx_types(struct dma_device *device)
#endif
#endif
- #if defined(CONFIG_ASYNC_PQ) || defined(CONFIG_ASYNC_PQ_MODULE)
+ #if IS_ENABLED(CONFIG_ASYNC_PQ)
if (!dma_has_cap(DMA_PQ, device->cap_mask))
return false;
diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index 1e1f2986eba8..faae0bfe1109 100644
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -240,8 +240,9 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
struct of_phandle_args dma_spec;
struct of_dma *ofdma;
struct dma_chan *chan;
- int count, i;
+ int count, i, start;
int ret_no_channel = -ENODEV;
+ static atomic_t last_index;
if (!np || !name) {
pr_err("%s: not enough information provided\n", __func__);
@@ -259,8 +260,15 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
return ERR_PTR(-ENODEV);
}
+ /*
+ * approximate an average distribution across multiple
+ * entries with the same name
+ */
+ start = atomic_inc_return(&last_index);
for (i = 0; i < count; i++) {
- if (of_dma_match_channel(np, name, i, &dma_spec))
+ if (of_dma_match_channel(np, name,
+ (i + start) % count,
+ &dma_spec))
continue;
mutex_lock(&of_dma_lock);
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 017433712833..30de0197263a 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -804,6 +804,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_single(
sg_dma_address(&sg) = buf;
sg_dma_len(&sg) = len;
+ if (!chan || !chan->device || !chan->device->device_prep_slave_sg)
+ return NULL;
+
return chan->device->device_prep_slave_sg(chan, &sg, 1,
dir, flags, NULL);
}
@@ -812,6 +815,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len,
enum dma_transfer_direction dir, unsigned long flags)
{
+ if (!chan || !chan->device || !chan->device->device_prep_slave_sg)
+ return NULL;
+
return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
dir, flags, NULL);
}
@@ -823,6 +829,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg(
enum dma_transfer_direction dir, unsigned long flags,
struct rio_dma_ext *rio_ext)
{
+ if (!chan || !chan->device || !chan->device->device_prep_slave_sg)
+ return NULL;
+
return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
dir, flags, rio_ext);
}
@@ -833,6 +842,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
size_t period_len, enum dma_transfer_direction dir,
unsigned long flags)
{
+ if (!chan || !chan->device || !chan->device->device_prep_dma_cyclic)
+ return NULL;
+
return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len,
period_len, dir, flags);
}
@@ -841,6 +853,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma(
struct dma_chan *chan, struct dma_interleaved_template *xt,
unsigned long flags)
{
+ if (!chan || !chan->device || !chan->device->device_prep_interleaved_dma)
+ return NULL;
+
return chan->device->device_prep_interleaved_dma(chan, xt, flags);
}
@@ -848,7 +863,7 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memset(
struct dma_chan *chan, dma_addr_t dest, int value, size_t len,
unsigned long flags)
{
- if (!chan || !chan->device)
+ if (!chan || !chan->device || !chan->device->device_prep_dma_memset)
return NULL;
return chan->device->device_prep_dma_memset(chan, dest, value,
@@ -861,6 +876,9 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_sg(
struct scatterlist *src_sg, unsigned int src_nents,
unsigned long flags)
{
+ if (!chan || !chan->device || !chan->device->device_prep_dma_sg)
+ return NULL;
+
return chan->device->device_prep_dma_sg(chan, dst_sg, dst_nents,
src_sg, src_nents, flags);
}
OpenPOWER on IntegriCloud