diff options
| author | Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com> | 2023-12-18 12:06:52 +0300 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2024-01-23 16:28:05 +0300 |
| commit | 633cd6fe6e1993ba80e0954c2db127a0b1a3e66f (patch) | |
| tree | c35675d99e6e5a94fe200555d18aaf61a9fa4e1b /drivers/spi | |
| parent | e267a5b3ec59ce88d6be21078e2deb807ca3b436 (diff) | |
| download | linux-633cd6fe6e1993ba80e0954c2db127a0b1a3e66f.tar.xz | |
spi: spi-cadence: Reverse the order of interleaved write and read operations
In the existing implementation, when executing interleaved write and read
operations in the ISR for a transfer length greater than the FIFO size,
the TXFIFO write precedes the RXFIFO read. Consequently, the initially
received data in the RXFIFO is pushed out and lost, leading to a failure
in data integrity. To address this issue, reverse the order of interleaved
operations and conduct the RXFIFO read followed by the TXFIFO write.
Fixes: 6afe2ae8dc48 ("spi: spi-cadence: Interleave write of TX and read of RX FIFO")
Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>
Link: https://msgid.link/r/20231218090652.18403-1-amit.kumar-mahapatra@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-cadence.c | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c index a50eb4db79de..e5140532071d 100644 --- a/drivers/spi/spi-cadence.c +++ b/drivers/spi/spi-cadence.c @@ -317,6 +317,15 @@ static void cdns_spi_process_fifo(struct cdns_spi *xspi, int ntx, int nrx) xspi->rx_bytes -= nrx; while (ntx || nrx) { + if (nrx) { + u8 data = cdns_spi_read(xspi, CDNS_SPI_RXD); + + if (xspi->rxbuf) + *xspi->rxbuf++ = data; + + nrx--; + } + if (ntx) { if (xspi->txbuf) cdns_spi_write(xspi, CDNS_SPI_TXD, *xspi->txbuf++); @@ -326,14 +335,6 @@ static void cdns_spi_process_fifo(struct cdns_spi *xspi, int ntx, int nrx) ntx--; } - if (nrx) { - u8 data = cdns_spi_read(xspi, CDNS_SPI_RXD); - - if (xspi->rxbuf) - *xspi->rxbuf++ = data; - - nrx--; - } } } |