[PATCH AUTOSEL 5.10 15/47] spi: stm32: make spurious and overrun interrupts visible

Sasha Levin
2021-03-02T19:48:10Z

From: Alain Volmat <alain.volmat@foss.st.com>

[ Upstream commit c64e7efe46b7de21937ef4b3594d9b1fc74f07df ]

We do not expect to receive spurious interrupts so rise a warning
if it happens.

RX overrun is an error condition that signals a corrupted RX
stream both in dma and in irq modes. Report the error and
abort the transfer in either cases.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Link: https://lore.kernel.org/r/1612551572-495-9-git-send-email-alain.volmat@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/spi/spi-stm32.c | 15 ++++-----------
1 file changed, 4 insertions(+), 11 deletions(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 6017209c6d2f..4bcdad084801 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -928,8 +928,8 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
mask |= STM32H7_SPI_SR_RXP;

if (!(sr & mask)) {
- dev_dbg(spi->dev, "spurious IT (sr=0x%08x, ier=0x%08x)\n",
- sr, ier);
+ dev_warn(spi->dev, "spurious IT (sr=0x%08x, ier=0x%08x)\n",
+ sr, ier);
spin_unlock_irqrestore(&spi->lock, flags);
return IRQ_NONE;
}
@@ -956,15 +956,8 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
}

if (sr & STM32H7_SPI_SR_OVR) {
- dev_warn(spi->dev, "Overrun: received value discarded\n");
- if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0)))
- stm32h7_spi_read_rxfifo(spi, false);
- /*
- * If overrun is detected while using DMA, it means that
- * something went wrong, so stop the current transfer
- */
- if (spi->cur_usedma)
- end = true;
+ dev_err(spi->dev, "Overrun: RX data lost\n");
+ end = true;
}

if (sr & STM32H7_SPI_SR_EOT) {
--
2.30.1