[PATCH v3 12/15] spi: qup: refactor spi_qup_prep_sg

Varadarajan Narayanan
2017-06-20T09:12:17Z

Take specific sgl and nent to be prepared. This is in
preparation for splitting DMA into multiple transacations, this
contains no code changes just refactoring.

Signed-off-by: Matthew McClintock <mmcclint@codeaurora.org>
Signed-off-by: Varadarajan Narayanan <varada@codeaurora.org>
---
drivers/spi/spi-qup.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)

diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c
index 026f25e..2423ee5 100644
--- a/drivers/spi/spi-qup.c
+++ b/drivers/spi/spi-qup.c
@@ -382,26 +382,19 @@ static void spi_qup_write(struct spi_qup *controller)
} while (remainder);
}

-static int spi_qup_prep_sg(struct spi_master *master, struct spi_transfer *xfer,
- enum dma_transfer_direction dir,
+static int spi_qup_prep_sg(struct spi_master *master, struct scatterlist *sgl,
+ unsigned int nents, enum dma_transfer_direction dir,
dma_async_tx_callback callback, void *data)
{
unsigned long flags = DMA_PREP_INTERRUPT | DMA_PREP_FENCE;
struct dma_async_tx_descriptor *desc;
- struct scatterlist *sgl;
struct dma_chan *chan;
dma_cookie_t cookie;
- unsigned int nents;

- if (dir == DMA_MEM_TO_DEV) {
+ if (dir == DMA_MEM_TO_DEV)
chan = master->dma_tx;
- nents = xfer->tx_sg.nents;
- sgl = xfer->tx_sg.sgl;
- } else {
+ else
chan = master->dma_rx;
- nents = xfer->rx_sg.nents;
- sgl = xfer->rx_sg.sgl;
- }

desc = dmaengine_prep_slave_sg(chan, sgl, nents, dir, flags);
if (IS_ERR_OR_NULL(desc))
@@ -444,8 +437,9 @@ static int spi_qup_do_dma(struct spi_device *spi, struct spi_transfer *xfer,
}

if (xfer->rx_buf) {
- ret = spi_qup_prep_sg(master, xfer, DMA_DEV_TO_MEM,
- spi_qup_dma_done, &qup->rxc);
+ ret = spi_qup_prep_sg(master, xfer->rx_sg.sgl,
+ xfer->rx_sg.nents, DMA_DEV_TO_MEM,
+ spi_qup_dma_done, &qup->rxc);
if (ret)
return ret;

@@ -453,8 +447,9 @@ static int spi_qup_do_dma(struct spi_device *spi, struct spi_transfer *xfer,
}

if (xfer->tx_buf) {
- ret = spi_qup_prep_sg(master, xfer, DMA_MEM_TO_DEV,
- spi_qup_dma_done, &qup->txc);
+ ret = spi_qup_prep_sg(master, xfer->tx_sg.sgl,
+ xfer->tx_sg.nents, DMA_MEM_TO_DEV,
+ spi_qup_dma_done, &qup->txc);
if (ret)
return ret;