[PATCH] spi: stm32: clear only asserted irq flags on interrupt

From: Tobias Schramm <t.schramm@manjaro.org>
To: Mark Brown <broonie@kernel.org>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre Torgue <alexandre.torgue@st.com>
Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org,
	Tobias Schramm <t.schramm@manjaro.org>
Subject: [PATCH] spi: stm32: clear only asserted irq flags on interrupt
Date: Tue,  4 Aug 2020 21:51:36 +0200	[thread overview]
Message-ID: <20200804195136.1485392-1-t.schramm@manjaro.org> (raw)

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>
---
 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 4c643dfc7fbb..4a21feae0103 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -966,7 +966,7 @@ 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);
 
-- 
2.26.0

