This is a note to let you know that I've just added the patch titled
spi: spi-rspi: Fix PIO fallback on RZ platforms
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
spi-spi-rspi-fix-pio-fallback-on-rz-platforms.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit babdc89bbd6c60c116b3440d6d2aee49ad0c335e
Author: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
Date: Thu Jul 21 15:34:49 2022 +0100
spi: spi-rspi: Fix PIO fallback on RZ platforms
[ Upstream commit b620aa3a7be346f04ae7789b165937615c6ee8d3 ]
RSPI IP on RZ/{A, G2L} SoC's has the same signal for both interrupt
and DMA transfer request. Setting DMARS register for DMA transfer
makes the signal to work as a DMA transfer request signal and
subsequent interrupt requests to the interrupt controller
are masked.
PIO fallback does not work as interrupt signal is disabled.
This patch fixes this issue by re-enabling the interrupts by
calling dmaengine_synchronize().
Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Link: https://lore.kernel.org/r/20220721143449.879257-1-biju.das.jz@xxxxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index 0524741d73b9..8ae2ac40b4b2 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -595,6 +595,10 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
rspi->dma_callbacked, HZ);
if (ret > 0 && rspi->dma_callbacked) {
ret = 0;
+ if (tx)
+ dmaengine_synchronize(rspi->ctlr->dma_tx);
+ if (rx)
+ dmaengine_synchronize(rspi->ctlr->dma_rx);
} else {
if (!ret) {
dev_err(&rspi->ctlr->dev, "DMA timeout\n");
