Commit 8f72de67 authored Sep 04, 2020 by Chris Packham Committed by Greg Kroah-Hartman Oct 07, 2020

spi: fsl-espi: Only process interrupts for expected events



[ Upstream commit b867eef4cf548cd9541225aadcdcee644669b9e1 ]

The SPIE register contains counts for the TX FIFO so any time the irq
handler was invoked we would attempt to process the RX/TX fifos. Use the
SPIM value to mask the events so that we only process interrupts that
were expected.

This was a latent issue exposed by commit 3282a3da25bd ("powerpc/64:
Implement soft interrupt replay in C").

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Link: https://lore.kernel.org/r/20200904002812.7300-1-chris.packham@alliedtelesis.co.nz


Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 487882d9

drivers/spi/spi-fsl-espi.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -559,13 +559,14 @@ static void fsl_espi_cpu_irq(struct fsl_espi *espi, u32 events)
		static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
		{
		struct fsl_espi *espi = context_data;
		u32 events;
		u32 events, mask;

		spin_lock(&espi->lock);

		/* Get interrupt events(tx/rx) */
		events = fsl_espi_read_reg(espi, ESPI_SPIE);
		if (!events) {
		mask = fsl_espi_read_reg(espi, ESPI_SPIM);
		if (!(events & mask)) {
		spin_unlock(&espi->lock);
		return IRQ_NONE;
		}