[PATCH 5.4 113/214] spi: stm32: clear only asserted irq flags on interrupt

Greg Kroah-Hartman
2020-09-01T16:21:42Z

From: Tobias Schramm <t.schramm@manjaro.org>

[ Upstream commit ae1ba50f1e706dfd7ce402ac52c1f1f10becad68 ]

Previously the stm32h7 interrupt thread cleared all non-masked interrupts.
If an interrupt was to occur during the handling of another interrupt its
flag would be unset, resulting in a lost interrupt.
This patches fixes the issue by clearing only the currently set interrupt
flags.

Signed-off-by: Tobias Schramm <t.schramm@manjaro.org>
Link: https://lore.kernel.org/r/20200804195136.1485392-1-t.schramm@manjaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/spi/spi-stm32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 7e92ab0cc9920..dc6334f67e6ae 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -962,7 +962,7 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0)))
stm32h7_spi_read_rxfifo(spi, false);

- writel_relaxed(mask, spi->base + STM32H7_SPI_IFCR);
+ writel_relaxed(sr & mask, spi->base + STM32H7_SPI_IFCR);

spin_unlock_irqrestore(&spi->lock, flags);

--
2.25.1