From 50a387e1f765a39c82ea98519205961578435d83 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Mar 2020 02:15:59 +0200 Subject: [PATCH] spi: spi-fsl-dspi: Fix interrupt-less DMA mode taking an XSPI code path [ Upstream commit 826b3a6a34619b934cdc33eeb961fcb99ce92c09 ] Interrupts are not necessary for DMA functionality, since the completion event is provided by the DMA driver. But if the driver fails to request the IRQ defined in the device tree, it will call dspi_poll which would make the driver hang waiting for data to become available in the RX FIFO. Fixes: c55be3059159 ("spi: spi-fsl-dspi: Use poll mode in case the platform IRQ is missing") Signed-off-by: Vladimir Oltean Tested-by: Michael Walle Link: https://lore.kernel.org/r/20200318001603.9650-9-olteanv@gmail.com Signed-off-by: Mark Brown Stable-dep-of: fa60c094c19b ("spi: spi-fsl-dspi: Clear completion counter before initiating transfer") Signed-off-by: Sasha Levin --- drivers/spi/spi-fsl-dspi.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c index 99d048acca29..7b62ecbe3632 100644 --- a/drivers/spi/spi-fsl-dspi.c +++ b/drivers/spi/spi-fsl-dspi.c @@ -793,13 +793,15 @@ static int dspi_transfer_one_message(struct spi_controller *ctlr, goto out; } - if (!dspi->irq) { - do { - status = dspi_poll(dspi); - } while (status == -EINPROGRESS); - } else if (trans_mode != DSPI_DMA_MODE) { - wait_for_completion(&dspi->xfer_done); - reinit_completion(&dspi->xfer_done); + if (trans_mode != DSPI_DMA_MODE) { + if (dspi->irq) { + wait_for_completion(&dspi->xfer_done); + reinit_completion(&dspi->xfer_done); + } else { + do { + status = dspi_poll(dspi); + } while (status == -EINPROGRESS); + } } if (transfer->delay_usecs)