diff options
| -rw-r--r-- | drivers/spi/spi-cadence.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c index 9b4e5b7013ae..af1a05e78492 100644 --- a/drivers/spi/spi-cadence.c +++ b/drivers/spi/spi-cadence.c @@ -388,11 +388,13 @@ static inline void cdns_spi_writer(struct cdns_spi *xspi) /** * cdns_spi_process_fifo - Fills the TX FIFO, and drain the RX FIFO + * @ctlr: Pointer to the spi_controller structure * @xspi: Pointer to the cdns_spi structure * @ntx: Number of bytes to pack into the TX FIFO * @nrx: Number of bytes to drain from the RX FIFO */ -static void cdns_spi_process_fifo(struct cdns_spi *xspi, int ntx, int nrx) +static void cdns_spi_process_fifo(struct spi_controller *ctlr, + struct cdns_spi *xspi, int ntx, int nrx) { ntx = clamp(ntx, 0, xspi->tx_bytes); nrx = clamp(nrx, 0, xspi->rx_bytes); @@ -407,6 +409,16 @@ static void cdns_spi_process_fifo(struct cdns_spi *xspi, int ntx, int nrx) } if (ntx) { + /* When xspi in busy condition, bytes may send failed, + * then spi control didn't work thoroughly, add one byte + * delay. Only in host mode; in target mode this delay + * causes data corruption as the target fails to prepare + * data in time. + */ + if (!spi_controller_is_target(ctlr) && + (cdns_spi_read(xspi, CDNS_SPI_ISR) & CDNS_SPI_IXR_TXFULL)) + udelay(10); + cdns_spi_writer(xspi); ntx--; } @@ -460,14 +472,14 @@ static irqreturn_t cdns_spi_irq(int irq, void *dev_id) cdns_spi_write(xspi, CDNS_SPI_THLD, 1); if (xspi->tx_bytes) { - cdns_spi_process_fifo(xspi, trans_cnt, trans_cnt); + cdns_spi_process_fifo(ctlr, xspi, trans_cnt, trans_cnt); } else { /* Fixed delay due to controller limitation with * RX_NEMPTY incorrect status * Xilinx AR:65885 contains more details */ udelay(10); - cdns_spi_process_fifo(xspi, 0, trans_cnt); + cdns_spi_process_fifo(ctlr, xspi, 0, trans_cnt); cdns_spi_write(xspi, CDNS_SPI_IDR, CDNS_SPI_IXR_DEFAULT); spi_finalize_current_transfer(ctlr); @@ -520,17 +532,11 @@ static int cdns_transfer_one(struct spi_controller *ctlr, cdns_spi_write(xspi, CDNS_SPI_THLD, xspi->tx_fifo_depth >> 1); } - /* When xspi in busy condition, bytes may send failed, - * then spi control didn't work thoroughly, add one byte delay - */ - if (cdns_spi_read(xspi, CDNS_SPI_ISR) & CDNS_SPI_IXR_TXFULL) - udelay(10); - xspi->n_bytes = cdns_spi_n_bytes(transfer); xspi->tx_bytes = DIV_ROUND_UP(xspi->tx_bytes, xspi->n_bytes); xspi->rx_bytes = DIV_ROUND_UP(xspi->rx_bytes, xspi->n_bytes); - cdns_spi_process_fifo(xspi, xspi->tx_fifo_depth, 0); + cdns_spi_process_fifo(ctlr, xspi, xspi->tx_fifo_depth, 0); cdns_spi_write(xspi, CDNS_SPI_IER, CDNS_SPI_IXR_DEFAULT); return transfer->len; |