diff options
| -rw-r--r-- | drivers/spi/spi-xilinx.c | 38 |
1 files changed, 24 insertions, 14 deletions
diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index a339c1e9997a..3009121173cd 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -270,6 +270,7 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) while (remaining_words) { int n_words, tx_words, rx_words; + u32 sr; n_words = min(remaining_words, xspi->buffer_size); @@ -284,24 +285,33 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) if (use_irq) { xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); wait_for_completion(&xspi->done); - } else - while (!(xspi->read_fn(xspi->regs + XSPI_SR_OFFSET) & - XSPI_SR_TX_EMPTY_MASK)) - ; - - /* A transmit has just completed. Process received data and - * check for more data to transmit. Always inhibit the - * transmitter while the Isr refills the transmit register/FIFO, - * or make sure it is stopped if we're done. - */ - if (use_irq) + /* A transmit has just completed. Process received data + * and check for more data to transmit. Always inhibit + * the transmitter while the Isr refills the transmit + * register/FIFO, or make sure it is stopped if we're + * done. + */ xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT, - xspi->regs + XSPI_CR_OFFSET); + xspi->regs + XSPI_CR_OFFSET); + sr = XSPI_SR_TX_EMPTY_MASK; + } else + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); /* Read out all the data from the Rx FIFO */ rx_words = n_words; - while (rx_words--) - xilinx_spi_rx(xspi); + while (rx_words) { + if ((sr & XSPI_SR_TX_EMPTY_MASK) && (rx_words > 1)) { + xilinx_spi_rx(xspi); + rx_words--; + continue; + } + + sr = xspi->read_fn(xspi->regs + XSPI_SR_OFFSET); + if (!(sr & XSPI_SR_RX_EMPTY_MASK)) { + xilinx_spi_rx(xspi); + rx_words--; + } + } remaining_words -= n_words; } |