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| author | Vladimir Oltean <vladimir.oltean@nxp.com> | 2020-03-18 02:15:55 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-03-18 22:44:56 +0000 |
| commit | c6c1e30a789b08de2e075cbd9705e81af3d2c7cc (patch) | |
| tree | 20056e13fe9ede82ab9734c6bf98fedc09dbad27 /drivers/spi | |
| parent | a957499bd437720d082d92657b7eb5cf5a62e893 (diff) | |
| download | linux-c6c1e30a789b08de2e075cbd9705e81af3d2c7cc.tar.gz linux-c6c1e30a789b08de2e075cbd9705e81af3d2c7cc.tar.bz2 linux-c6c1e30a789b08de2e075cbd9705e81af3d2c7cc.zip | |
spi: spi-fsl-dspi: Avoid reading more data than written in EOQ mode
If dspi->words_in_flight is populated with the hardware FIFO size,
then in dspi_fifo_read it will attempt to read more data at the end of a
buffer that is not a multiple of 16 bytes in length. It will probably
time out attempting to do so.
So limit the num_fifo_entries variable to the actual number of FIFO
entries that is going to be used.
Fixes: d59c90a2400f ("spi: spi-fsl-dspi: Convert TCFQ users to XSPI FIFO mode")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200318001603.9650-5-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-fsl-dspi.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c index 8f2b73cc6ed7..51224b772680 100644 --- a/drivers/spi/spi-fsl-dspi.c +++ b/drivers/spi/spi-fsl-dspi.c @@ -739,13 +739,16 @@ static void dspi_eoq_fifo_write(struct fsl_dspi *dspi) int num_fifo_entries = dspi->devtype_data->fifo_size; u16 xfer_cmd = dspi->tx_cmd; + if (num_fifo_entries * dspi->oper_word_size > dspi->len) + num_fifo_entries = dspi->len / dspi->oper_word_size; + dspi->words_in_flight = num_fifo_entries; /* Fill TX FIFO with as many transfers as possible */ - while (dspi->len && num_fifo_entries--) { + while (num_fifo_entries--) { dspi->tx_cmd = xfer_cmd; /* Request EOQF for last transfer in FIFO */ - if (dspi->len == dspi->oper_word_size || num_fifo_entries == 0) + if (num_fifo_entries == 0) dspi->tx_cmd |= SPI_PUSHR_CMD_EOQ; /* Write combined TX FIFO and CMD FIFO entry */ dspi_pushr_write(dspi); |