@@ -207,12 +207,10 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws)
return rxdesc;
}
-static void dw_spi_dma_setup(struct dw_spi *dws)
+static int mid_spi_dma_setup(struct dw_spi *dws)
{
u16 dma_ctrl = 0;
- spi_enable_chip(dws, 0);
-
dw_writew(dws, DW_SPI_DMARDLR, 0xf);
dw_writew(dws, DW_SPI_DMATDLR, 0x10);
@@ -222,21 +220,17 @@ static void dw_spi_dma_setup(struct dw_spi *dws)
dma_ctrl |= SPI_DMA_RDMAE;
dw_writew(dws, DW_SPI_DMACR, dma_ctrl);
- spi_enable_chip(dws, 1);
+ return 0;
}
-static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change)
+static int mid_spi_dma_transfer(struct dw_spi *dws)
{
struct dma_async_tx_descriptor *txdesc, *rxdesc;
- /* 1. setup DMA related registers */
- if (cs_change)
- dw_spi_dma_setup(dws);
-
- /* 2. Prepare the TX dma transfer */
+ /* Prepare the TX dma transfer */
txdesc = dw_spi_dma_prepare_tx(dws);
- /* 3. Prepare the RX dma transfer */
+ /* Prepare the RX dma transfer */
rxdesc = dw_spi_dma_prepare_rx(dws);
/* rx must be started before tx due to spi instinct */
@@ -258,6 +252,7 @@ static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change)
static struct dw_spi_dma_ops mid_dma_ops = {
.dma_init = mid_spi_dma_init,
.dma_exit = mid_spi_dma_exit,
+ .dma_setup = mid_spi_dma_setup,
.dma_transfer = mid_spi_dma_transfer,
};
#endif
@@ -316,11 +316,11 @@ static int dw_spi_transfer_one(struct spi_master *master,
struct dw_spi *dws = spi_master_get_devdata(master);
struct chip_data *chip = spi_get_ctldata(spi);
u8 imask = 0;
- u8 cs_change = 0;
u16 txlevel = 0;
u16 clk_div = 0;
u32 speed = 0;
u32 cr0 = 0;
+ int ret;
dws->n_bytes = chip->n_bytes;
dws->dma_width = chip->dma_width;
@@ -332,8 +332,6 @@ static int dw_spi_transfer_one(struct spi_master *master,
dws->rx = transfer->rx_buf;
dws->rx_end = dws->rx + transfer->len;
dws->len = transfer->len;
- if (chip != dws->prev_chip)
- cs_change = 1;
spi_enable_chip(dws, 0);
@@ -397,7 +395,13 @@ static int dw_spi_transfer_one(struct spi_master *master,
* Interrupt mode
* we only need set the TXEI IRQ, as TX/RX always happen syncronizely
*/
- if (!dws->dma_mapped && !chip->poll_mode) {
+ if (dws->dma_mapped) {
+ ret = dws->dma_ops->dma_setup(dws);
+ if (ret < 0) {
+ spi_enable_chip(dws, 1);
+ return ret;
+ }
+ } else if (!chip->poll_mode) {
txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes);
dw_writew(dws, DW_SPI_TXFLTR, txlevel);
@@ -411,11 +415,11 @@ static int dw_spi_transfer_one(struct spi_master *master,
spi_enable_chip(dws, 1);
- if (cs_change)
- dws->prev_chip = chip;
-
- if (dws->dma_mapped)
- dws->dma_ops->dma_transfer(dws, cs_change);
+ if (dws->dma_mapped) {
+ ret = dws->dma_ops->dma_transfer(dws);
+ if (ret < 0)
+ return ret;
+ }
if (chip->poll_mode)
return poll_transfer(dws);
@@ -546,7 +550,6 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
dws->master = master;
dws->type = SSI_MOTO_SPI;
- dws->prev_chip = NULL;
dws->dma_inited = 0;
dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60);
snprintf(dws->name, sizeof(dws->name), "dw_spi%d", dws->bus_num);
@@ -91,7 +91,8 @@ struct dw_spi;
struct dw_spi_dma_ops {
int (*dma_init)(struct dw_spi *dws);
void (*dma_exit)(struct dw_spi *dws);
- int (*dma_transfer)(struct dw_spi *dws, int cs_change);
+ int (*dma_setup)(struct dw_spi *dws);
+ int (*dma_transfer)(struct dw_spi *dws);
};
struct dw_spi {
@@ -109,7 +110,6 @@ struct dw_spi {
u16 num_cs; /* supported slave numbers */
/* Current message transfer state info */
- struct chip_data *prev_chip;
size_t len;
void *tx;
void *tx_end;
The patch splits DMA preparatory code to dma_setup() callback. The change also converts transfer_one() to program DMA whenever the transfer is DMA mapped. The change is a follow up of the converion to use SPI core transfer_one_message(). Since the DMA mapped transfers can be interleaved with PIO ones the DMA related configuration should respect that. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> --- drivers/spi/spi-dw-mid.c | 17 ++++++----------- drivers/spi/spi-dw.c | 23 +++++++++++++---------- drivers/spi/spi-dw.h | 4 ++-- 3 files changed, 21 insertions(+), 23 deletions(-)