[PATCH v3 6/6] dmaengine: imx-sdma: add sdma_transfer_init to decrease code overlap

From: Robin Gong
Date: Mon Jun 11 2018 - 03:00:55 EST


There are lot of codes overlap between prep_sg and prep_cyclic function.
Add sdma_transfer_init() function to elimated the code overlap.

Signed-off-by: Robin Gong <yibin.gong@xxxxxxx>
---
drivers/dma/imx-sdma.c | 83 ++++++++++++++++++++++----------------------------
1 file changed, 37 insertions(+), 46 deletions(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 0b0588d2..486ebfe 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -1254,6 +1254,40 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
clk_disable(sdma->clk_ahb);
}

+static struct sdma_desc *sdma_transfer_init(struct sdma_channel *sdmac,
+ enum dma_transfer_direction direction, u32 bds)
+{
+ struct sdma_desc *desc;
+
+ desc = kzalloc((sizeof(*desc)), GFP_KERNEL);
+ if (!desc)
+ goto err_out;
+
+ sdmac->status = DMA_IN_PROGRESS;
+ sdmac->direction = direction;
+ sdmac->flags = 0;
+
+ desc->chn_count = 0;
+ desc->chn_real_count = 0;
+ desc->buf_tail = 0;
+ desc->buf_ptail = 0;
+ desc->sdmac = sdmac;
+ desc->num_bd = bds;
+
+ if (sdma_alloc_bd(desc))
+ goto err_desc_out;
+
+ if (sdma_load_context(sdmac))
+ goto err_desc_out;
+
+ return desc;
+
+err_desc_out:
+ kfree(desc);
+err_out:
+ return NULL;
+}
+
static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl,
unsigned int sg_len, enum dma_transfer_direction direction,
@@ -1266,36 +1300,13 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
struct scatterlist *sg;
struct sdma_desc *desc;

- if (sdmac->status == DMA_IN_PROGRESS)
- return NULL;
- sdmac->status = DMA_IN_PROGRESS;
-
- sdmac->flags = 0;
-
- desc = kzalloc((sizeof(*desc)), GFP_KERNEL);
+ desc = sdma_transfer_init(sdmac, direction, sg_len);
if (!desc)
goto err_out;

- desc->buf_tail = 0;
- desc->buf_ptail = 0;
- desc->sdmac = sdmac;
- desc->num_bd = sg_len;
- desc->chn_real_count = 0;
-
- if (sdma_alloc_bd(desc)) {
- kfree(desc);
- goto err_out;
- }
-
dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
sg_len, channel);

- sdmac->direction = direction;
- ret = sdma_load_context(sdmac);
- if (ret)
- goto err_bd_out;
-
- desc->chn_count = 0;
for_each_sg(sgl, sg, sg_len, i) {
struct sdma_buffer_descriptor *bd = &desc->bd[i];
int param;
@@ -1371,38 +1382,18 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
struct sdma_engine *sdma = sdmac->sdma;
int num_periods = buf_len / period_len;
int channel = sdmac->channel;
- int ret, i = 0, buf = 0;
+ int i = 0, buf = 0;
struct sdma_desc *desc;

dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);

- if (sdmac->status == DMA_IN_PROGRESS)
- return NULL;
-
- sdmac->status = DMA_IN_PROGRESS;
-
- desc = kzalloc((sizeof(*desc)), GFP_KERNEL);
+ desc = sdma_transfer_init(sdmac, direction, num_periods);
if (!desc)
goto err_out;

- desc->buf_tail = 0;
- desc->buf_ptail = 0;
- desc->sdmac = sdmac;
- desc->num_bd = num_periods;
- desc->chn_real_count = 0;
desc->period_len = period_len;

sdmac->flags |= IMX_DMA_SG_LOOP;
- sdmac->direction = direction;
-
- if (sdma_alloc_bd(desc)) {
- kfree(desc);
- goto err_bd_out;
- }
-
- ret = sdma_load_context(sdmac);
- if (ret)
- goto err_bd_out;

if (period_len > 0xffff) {
dev_err(sdma->dev, "SDMA channel %d: maximum period size exceeded: %zu > %d\n",
--
2.7.4