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-rw-r--r--drivers/spi/spi-cadence.c42
1 files changed, 15 insertions, 27 deletions
diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c
index ac85d5562212..b0ccb138e356 100644
--- a/drivers/spi/spi-cadence.c
+++ b/drivers/spi/spi-cadence.c
@@ -304,13 +304,11 @@ static int cdns_spi_setup_transfer(struct spi_device *spi,
* cdns_spi_fill_tx_fifo - Fills the TX FIFO with as many bytes as possible
* @xspi: Pointer to the cdns_spi structure
*/
-static void cdns_spi_fill_tx_fifo(struct cdns_spi *xspi)
+static void cdns_spi_fill_tx_fifo(struct cdns_spi *xspi, unsigned int avail)
{
unsigned long trans_cnt = 0;
- while ((trans_cnt < xspi->tx_fifo_depth) &&
- (xspi->tx_bytes > 0)) {
-
+ while ((trans_cnt < avail) && (xspi->tx_bytes > 0)) {
/* When xspi in busy condition, bytes may send failed,
* then spi control did't work thoroughly, add one byte delay
*/
@@ -381,33 +379,23 @@ static irqreturn_t cdns_spi_irq(int irq, void *dev_id)
spi_finalize_current_transfer(ctlr);
status = IRQ_HANDLED;
} else if (intr_status & CDNS_SPI_IXR_TXOW) {
- int trans_cnt = cdns_spi_read(xspi, CDNS_SPI_THLD);
+ int threshold = cdns_spi_read(xspi, CDNS_SPI_THLD);
+ int trans_cnt = xspi->rx_bytes - xspi->tx_bytes;
+
+ if (threshold > 1)
+ trans_cnt -= threshold;
+
/* Set threshold to one if number of pending are
* less than half fifo
*/
if (xspi->tx_bytes < xspi->tx_fifo_depth >> 1)
cdns_spi_write(xspi, CDNS_SPI_THLD, 1);
- while (trans_cnt) {
- cdns_spi_read_rx_fifo(xspi, 1);
-
- if (xspi->tx_bytes) {
- if (xspi->txbuf)
- cdns_spi_write(xspi, CDNS_SPI_TXD,
- *xspi->txbuf++);
- else
- cdns_spi_write(xspi, CDNS_SPI_TXD, 0);
- xspi->tx_bytes--;
- }
- trans_cnt--;
- }
- if (!xspi->tx_bytes) {
- /* Fixed delay due to controller limitation with
- * RX_NEMPTY incorrect status
- * Xilinx AR:65885 contains more details
- */
- udelay(10);
- cdns_spi_read_rx_fifo(xspi, xspi->rx_bytes);
+ cdns_spi_read_rx_fifo(xspi, trans_cnt);
+
+ if (xspi->tx_bytes) {
+ cdns_spi_fill_tx_fifo(xspi, trans_cnt);
+ } else {
cdns_spi_write(xspi, CDNS_SPI_IDR,
CDNS_SPI_IXR_DEFAULT);
spi_finalize_current_transfer(ctlr);
@@ -456,10 +444,10 @@ static int cdns_transfer_one(struct spi_controller *ctlr,
/* Set TX empty threshold to half of FIFO depth
* only if TX bytes are more than half FIFO depth.
*/
- if (xspi->tx_bytes > (xspi->tx_fifo_depth >> 1))
+ if (xspi->tx_bytes > xspi->tx_fifo_depth)
cdns_spi_write(xspi, CDNS_SPI_THLD, xspi->tx_fifo_depth >> 1);
- cdns_spi_fill_tx_fifo(xspi);
+ cdns_spi_fill_tx_fifo(xspi, xspi->tx_fifo_depth);
spi_transfer_delay_exec(transfer);
cdns_spi_write(xspi, CDNS_SPI_IER, CDNS_SPI_IXR_DEFAULT);