@@ -195,10 +195,6 @@ struct rspi_data {
int rx_irq, tx_irq;
const struct spi_ops *ops;
- /* for dmaengine */
- struct dma_chan *chan_tx;
- struct dma_chan *chan_rx;
-
unsigned dma_callbacked:1;
unsigned byte_access:1;
};
@@ -251,6 +247,7 @@ struct spi_ops {
struct spi_transfer *xfer);
u16 mode_bits;
u16 flags;
+ u16 fifo_size;
};
/*
@@ -466,39 +463,16 @@ static void rspi_dma_complete(void *arg)
wake_up_interruptible(&rspi->wait);
}
-static int rspi_dma_map_sg(struct scatterlist *sg, const void *buf,
- unsigned len, struct dma_chan *chan,
- enum dma_transfer_direction dir)
-{
- sg_init_table(sg, 1);
- sg_set_buf(sg, buf, len);
- sg_dma_len(sg) = len;
- return dma_map_sg(chan->device->dev, sg, 1, dir);
-}
-
-static void rspi_dma_unmap_sg(struct scatterlist *sg, struct dma_chan *chan,
- enum dma_transfer_direction dir)
-{
- dma_unmap_sg(chan->device->dev, sg, 1, dir);
-}
-
static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
{
- struct scatterlist sg;
- const void *buf = t->tx_buf;
struct dma_async_tx_descriptor *desc;
- unsigned int len = t->len;
- int ret = 0;
-
- if (!rspi_dma_map_sg(&sg, buf, len, rspi->chan_tx, DMA_TO_DEVICE))
- return -EFAULT;
+ int ret;
- desc = dmaengine_prep_slave_sg(rspi->chan_tx, &sg, 1, DMA_TO_DEVICE,
+ desc = dmaengine_prep_slave_sg(rspi->master->dma_tx, t->tx_sg.sgl,
+ t->tx_sg.nents, DMA_TO_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
- if (!desc) {
- ret = -EIO;
- goto end;
- }
+ if (!desc)
+ return -EIO;
/*
* DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
@@ -513,7 +487,7 @@ static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
desc->callback = rspi_dma_complete;
desc->callback_param = rspi;
dmaengine_submit(desc);
- dma_async_issue_pending(rspi->chan_tx);
+ dma_async_issue_pending(rspi->master->dma_tx);
ret = wait_event_interruptible_timeout(rspi->wait,
rspi->dma_callbacked, HZ);
@@ -524,9 +498,6 @@ static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
rspi_disable_irq(rspi, SPCR_SPTIE);
enable_irq(rspi->tx_irq);
-
-end:
- rspi_dma_unmap_sg(&sg, rspi->chan_tx, DMA_TO_DEVICE);
return ret;
}
@@ -562,39 +533,22 @@ static void qspi_receive_init(const struct rspi_data *rspi)
static int rspi_send_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
{
- struct scatterlist sg_rx, sg_tx;
- const void *tx_buf = t->tx_buf;
- void *rx_buf = t->rx_buf;
struct dma_async_tx_descriptor *desc_tx, *desc_rx;
- unsigned int len = t->len;
- int ret = 0;
+ int ret;
/* prepare transmit transfer */
- if (!rspi_dma_map_sg(&sg_tx, tx_buf, len, rspi->chan_tx,
- DMA_TO_DEVICE))
- return -EFAULT;
-
- desc_tx = dmaengine_prep_slave_sg(rspi->chan_tx, &sg_tx, 1,
- DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
- if (!desc_tx) {
- ret = -EIO;
- goto end_tx_mapped;
- }
+ desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx, t->tx_sg.sgl,
+ t->tx_sg.nents, DMA_TO_DEVICE,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc_tx)
+ return -EIO;
/* prepare receive transfer */
- if (!rspi_dma_map_sg(&sg_rx, rx_buf, len, rspi->chan_rx,
- DMA_FROM_DEVICE)) {
- ret = -EFAULT;
- goto end_tx_mapped;
-
- }
- desc_rx = dmaengine_prep_slave_sg(rspi->chan_rx, &sg_rx, 1,
- DMA_FROM_DEVICE,
+ desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx, t->rx_sg.sgl,
+ t->rx_sg.nents, DMA_FROM_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
- if (!desc_rx) {
- ret = -EIO;
- goto end;
- }
+ if (!desc_rx)
+ return -EIO;
rspi_receive_init(rspi);
@@ -613,11 +567,11 @@ static int rspi_send_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
desc_rx->callback = rspi_dma_complete;
desc_rx->callback_param = rspi;
dmaengine_submit(desc_rx);
- dma_async_issue_pending(rspi->chan_rx);
+ dma_async_issue_pending(rspi->master->dma_rx);
desc_tx->callback = NULL; /* No callback */
dmaengine_submit(desc_tx);
- dma_async_issue_pending(rspi->chan_tx);
+ dma_async_issue_pending(rspi->master->dma_tx);
ret = wait_event_interruptible_timeout(rspi->wait,
rspi->dma_callbacked, HZ);
@@ -631,19 +585,21 @@ static int rspi_send_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
if (rspi->rx_irq != rspi->tx_irq)
enable_irq(rspi->rx_irq);
-end:
- rspi_dma_unmap_sg(&sg_rx, rspi->chan_rx, DMA_FROM_DEVICE);
-end_tx_mapped:
- rspi_dma_unmap_sg(&sg_tx, rspi->chan_tx, DMA_TO_DEVICE);
return ret;
}
-static int rspi_is_dma(const struct rspi_data *rspi, struct spi_transfer *t)
+static bool __rspi_can_dma(const struct rspi_data *rspi,
+ const struct spi_transfer *xfer)
{
- if (rspi->chan_tx)
- return 1;
+ return xfer->len > rspi->ops->fifo_size;
+}
- return 0;
+static bool rspi_can_dma(struct spi_master *master, struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct rspi_data *rspi = spi_master_get_devdata(master);
+
+ return __rspi_can_dma(rspi, xfer);
}
static int rspi_transfer_out_in(struct rspi_data *rspi,
@@ -676,7 +632,7 @@ static int rspi_transfer_one(struct spi_master *master, struct spi_device *spi,
{
struct rspi_data *rspi = spi_master_get_devdata(master);
- if (!rspi_is_dma(rspi, xfer))
+ if (!master->can_dma || !__rspi_can_dma(rspi, xfer))
return rspi_transfer_out_in(rspi, xfer);
if (xfer->rx_buf)
@@ -976,7 +932,7 @@ static struct dma_chan *rspi_request_dma_chan(struct device *dev,
return chan;
}
-static int rspi_request_dma(struct device *dev, struct rspi_data *rspi,
+static int rspi_request_dma(struct device *dev, struct spi_master *master,
const struct resource *res)
{
const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
@@ -984,31 +940,32 @@ static int rspi_request_dma(struct device *dev, struct rspi_data *rspi,
if (!rspi_pd || !rspi_pd->dma_rx_id || !rspi_pd->dma_tx_id)
return 0; /* The driver assumes no error. */
- rspi->chan_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM,
- rspi_pd->dma_rx_id,
- res->start + RSPI_SPDR);
- if (!rspi->chan_rx)
+ master->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM,
+ rspi_pd->dma_rx_id,
+ res->start + RSPI_SPDR);
+ if (!master->dma_rx)
return -ENODEV;
- rspi->chan_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV,
- rspi_pd->dma_tx_id,
- res->start + RSPI_SPDR);
- if (!rspi->chan_tx) {
- dma_release_channel(rspi->chan_rx);
- rspi->chan_rx = NULL;
+ master->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV,
+ rspi_pd->dma_tx_id,
+ res->start + RSPI_SPDR);
+ if (!master->dma_tx) {
+ dma_release_channel(master->dma_rx);
+ master->dma_rx = NULL;
return -ENODEV;
}
+ master->can_dma = rspi_can_dma;
dev_info(dev, "DMA available");
return 0;
}
static void rspi_release_dma(struct rspi_data *rspi)
{
- if (rspi->chan_tx)
- dma_release_channel(rspi->chan_tx);
- if (rspi->chan_rx)
- dma_release_channel(rspi->chan_rx);
+ if (rspi->master->dma_tx)
+ dma_release_channel(rspi->master->dma_tx);
+ if (rspi->master->dma_rx)
+ dma_release_channel(rspi->master->dma_rx);
}
static int rspi_remove(struct platform_device *pdev)
@@ -1026,6 +983,7 @@ static const struct spi_ops rspi_ops = {
.transfer_one = rspi_transfer_one,
.mode_bits = SPI_CPHA | SPI_CPOL | SPI_LOOP,
.flags = SPI_MASTER_MUST_TX,
+ .fifo_size = 8,
};
static const struct spi_ops rspi_rz_ops = {
@@ -1033,6 +991,7 @@ static const struct spi_ops rspi_rz_ops = {
.transfer_one = rspi_rz_transfer_one,
.mode_bits = SPI_CPHA | SPI_CPOL | SPI_LOOP,
.flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
+ .fifo_size = 8, /* 8 for TX, 32 for RX */
};
static const struct spi_ops qspi_ops = {
@@ -1042,6 +1001,7 @@ static const struct spi_ops qspi_ops = {
SPI_TX_DUAL | SPI_TX_QUAD |
SPI_RX_DUAL | SPI_RX_QUAD,
.flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX,
+ .fifo_size = 32,
};
#ifdef CONFIG_OF
@@ -1199,7 +1159,7 @@ static int rspi_probe(struct platform_device *pdev)
goto error2;
}
- ret = rspi_request_dma(&pdev->dev, rspi, res);
+ ret = rspi_request_dma(&pdev->dev, master, res);
if (ret < 0)
dev_warn(&pdev->dev, "DMA not available, using PIO\n");
Use the SPI core DMA mapping framework instead of our own. If available, DMA is used for transfers larger than the FIFO size (8 or 32 bytes). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- drivers/spi/spi-rspi.c | 140 ++++++++++++++++++------------------------------- 1 file changed, 50 insertions(+), 90 deletions(-)