6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Larisa Grigore larisa.grigore@nxp.com
[ Upstream commit 7aba292eb15389073c7f3bd7847e3862dfdf604d ]
If, in a previous transfer, the controller sends more data than expected by the DSPI target, SR.RFDF (RX FIFO is not empty) will remain asserted. When flushing the FIFOs at the beginning of a new transfer (writing 1 into MCR.CLR_TXF and MCR.CLR_RXF), SR.RFDF should also be cleared. Otherwise, when running in target mode with DMA, if SR.RFDF remains asserted, the DMA callback will be fired before the controller sends any data.
Take this opportunity to reset all Status Register fields.
Fixes: 5ce3cc567471 ("spi: spi-fsl-dspi: Provide support for DSPI slave mode operation (Vybryd vf610)") Signed-off-by: Larisa Grigore larisa.grigore@nxp.com Signed-off-by: James Clark james.clark@linaro.org Link: https://patch.msgid.link/20250522-james-nxp-spi-v2-3-bea884630cfb@linaro.org Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-fsl-dspi.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c index 72d83c8b9cbff..7dd94369abb47 100644 --- a/drivers/spi/spi-fsl-dspi.c +++ b/drivers/spi/spi-fsl-dspi.c @@ -980,6 +980,8 @@ static int dspi_transfer_one_message(struct spi_controller *ctlr, SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF, SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
+ regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR); + spi_take_timestamp_pre(dspi->ctlr, dspi->cur_transfer, dspi->progress, !dspi->irq);