Code reorg for transfer prepare and bus width check to make code
cleaner.
Signed-off-by: Robin Gong <b38...@freescale.com>
---
drivers/dma/imx-sdma.c | 127 +++++++++++++++++++++++--------------------------
1 file changed, 60 insertions(+), 67 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 377bb18..f2dee57 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -1026,6 +1026,52 @@ static void sdma_free_chan_resources(struct dma_chan
*chan)
clk_disable(sdma->clk_ahb);
}
+static int sdma_transfer_init(struct sdma_channel *sdmac,
+ enum dma_transfer_direction direction)
+{
+ int ret = 0;
+
+ sdmac->status = DMA_IN_PROGRESS;
+ sdmac->buf_tail = 0;
+ sdmac->flags = 0;
+ sdmac->direction = direction;
+
+ ret = sdma_load_context(sdmac);
+ if (ret)
+ return ret;
+
+ sdmac->chn_count = 0;
+
+ return ret;
+}
+
+static int check_bd_buswidth(struct sdma_buffer_descriptor *bd,
+ struct sdma_channel *sdmac, int count,
+ dma_addr_t dma_dst, dma_addr_t dma_src)
+{
+ int ret = 0;
+
+ switch (sdmac->word_size) {
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ bd->mode.command = 0;
+ if ((count | dma_dst | dma_src) & 3)
+ ret = -EINVAL;
+ break;
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ bd->mode.command = 2;
+ if ((count | dma_dst | dma_src) & 1)
+ ret = -EINVAL;
+ break;
+ case DMA_SLAVE_BUSWIDTH_1_BYTE:
+ bd->mode.command = 1;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
static struct dma_async_tx_descriptor *sdma_prep_memcpy(
struct dma_chan *chan, dma_addr_t dma_dst,
dma_addr_t dma_src, size_t len, unsigned long flags)
@@ -1034,7 +1080,7 @@ static struct dma_async_tx_descriptor *sdma_prep_memcpy(
struct sdma_engine *sdma = sdmac->sdma;
int channel = sdmac->channel;
size_t count;
- int i = 0, param, ret;
+ int i = 0, param;
struct sdma_buffer_descriptor *bd;
if (!chan || !len || sdmac->status == DMA_IN_PROGRESS)
@@ -1046,21 +1092,12 @@ static struct dma_async_tx_descriptor *sdma_prep_memcpy(
goto err_out;
}
- sdmac->status = DMA_IN_PROGRESS;
-
- sdmac->buf_tail = 0;
-
dev_dbg(sdma->dev, "memcpy: %pad->%pad, len=%zu, channel=%d.\n",
&dma_src, &dma_dst, len, channel);
- sdmac->direction = DMA_MEM_TO_MEM;
-
- ret = sdma_load_context(sdmac);
- if (ret)
+ if (sdma_transfer_init(sdmac, DMA_MEM_TO_MEM))
goto err_out;
- sdmac->chn_count = 0;
-
do {
count = min_t(size_t, len, SDMA_BD_MAX_CNT);
bd = &sdmac->bd[i];
@@ -1068,28 +1105,8 @@ static struct dma_async_tx_descriptor *sdma_prep_memcpy(
bd->ext_buffer_addr = dma_dst;
bd->mode.count = count;
- if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
- ret = -EINVAL;
+ if (check_bd_buswidth(bd, sdmac, count, dma_dst, dma_src))
goto err_out;
- }
-
- switch (sdmac->word_size) {
- case DMA_SLAVE_BUSWIDTH_4_BYTES:
- bd->mode.command = 0;
- if ((count | dma_dst | dma_src) & 3)
- return NULL;
- break;
- case DMA_SLAVE_BUSWIDTH_2_BYTES:
- bd->mode.command = 2;
- if ((count | dma_dst | dma_src) & 1)
- return NULL;
- break;
- case DMA_SLAVE_BUSWIDTH_1_BYTE:
- bd->mode.command = 1;
- break;
- default:
- return NULL;
- }
dma_src += count;
dma_dst += count;
@@ -1141,21 +1158,10 @@ static struct dma_async_tx_descriptor *sdma_prep_sg(
if (sdmac->status == DMA_IN_PROGRESS)
return NULL;
- sdmac->status = DMA_IN_PROGRESS;
-
- sdmac->flags = 0;
-
- sdmac->buf_tail = 0;
dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
src_nents, channel);
- sdmac->direction = direction;
-
- ret = sdma_load_context(sdmac);
- if (ret)
- goto err_out;
-
if (src_nents > NUM_BD) {
dev_err(sdma->dev, "SDMA channel %d: maximum number of sg
exceeded: %d > %d\n",
channel, src_nents, NUM_BD);
@@ -1163,7 +1169,9 @@ static struct dma_async_tx_descriptor *sdma_prep_sg(
goto err_out;
}
- sdmac->chn_count = 0;
+ if (sdma_transfer_init(sdmac, direction))
+ goto err_out;
+
for_each_sg(src_sg, sg_src, src_nents, i) {
struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
int param;
@@ -1187,30 +1195,15 @@ static struct dma_async_tx_descriptor *sdma_prep_sg(
bd->mode.count = count;
sdmac->chn_count += count;
- if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
- ret = -EINVAL;
+ if (direction == DMA_MEM_TO_MEM)
+ ret = check_bd_buswidth(bd, sdmac, count,
+ sg_dst->dma_address,
+ sg_src->dma_address);
+ else
+ ret = check_bd_buswidth(bd, sdmac, count, 0,
+ sg_src->dma_address);
+ if (ret)
goto err_out;
- }
-
- switch (sdmac->word_size) {
- case DMA_SLAVE_BUSWIDTH_4_BYTES:
- bd->mode.command = 0;
- if ((count | sg_src->dma_address | (sg_dst &&
- (sg_dst->dma_address))) & 3)
- return NULL;
- break;
- case DMA_SLAVE_BUSWIDTH_2_BYTES:
- bd->mode.command = 2;
- if ((count | sg_src->dma_address |
- (sg_dst && (sg_dst->dma_address))) & 1)
- return NULL;
- break;
- case DMA_SLAVE_BUSWIDTH_1_BYTE:
- bd->mode.command = 1;
- break;
- default:
- return NULL;
- }
param = BD_DONE | BD_EXTD | BD_CONT;
--
1.9.1
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