diff options
Diffstat (limited to 'drivers/spi/spi-lantiq-ssc.c')
| -rw-r--r-- | drivers/spi/spi-lantiq-ssc.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/spi/spi-lantiq-ssc.c b/drivers/spi/spi-lantiq-ssc.c index d5976615d924..dc740b5f720b 100644 --- a/drivers/spi/spi-lantiq-ssc.c +++ b/drivers/spi/spi-lantiq-ssc.c @@ -187,6 +187,7 @@ struct lantiq_ssc_spi { unsigned int tx_fifo_size; unsigned int rx_fifo_size; unsigned int base_cs; + unsigned int fdx_tx_level; }; static u32 lantiq_ssc_readl(const struct lantiq_ssc_spi *spi, u32 reg) @@ -484,6 +485,7 @@ static void tx_fifo_write(struct lantiq_ssc_spi *spi) u32 data; unsigned int tx_free = tx_fifo_free(spi); + spi->fdx_tx_level = 0; while (spi->tx_todo && tx_free) { switch (spi->bits_per_word) { case 2 ... 8: @@ -512,6 +514,7 @@ static void tx_fifo_write(struct lantiq_ssc_spi *spi) lantiq_ssc_writel(spi, data, LTQ_SPI_TB); tx_free--; + spi->fdx_tx_level++; } } @@ -523,6 +526,13 @@ static void rx_fifo_read_full_duplex(struct lantiq_ssc_spi *spi) u32 data; unsigned int rx_fill = rx_fifo_level(spi); + /* + * Wait until all expected data to be shifted in. + * Otherwise, rx overrun may occur. + */ + while (rx_fill != spi->fdx_tx_level) + rx_fill = rx_fifo_level(spi); + while (rx_fill) { data = lantiq_ssc_readl(spi, LTQ_SPI_RB); |