spi: spi-fsl-lpspi: Fix transmissions when using CONT

[ Upstream commit 782a7c73078e1301c0c427f21c06377d77dfa541 ]

Commit 6a130448498c ("spi: lpspi: Fix wrong transmission when don't use
CONT") breaks transmissions when CONT is used. The TDIE interrupt should
not be disabled in all cases. If CONT is used and the TX transfer is not
yet completed yet, but the interrupt handler is called because there are
characters to be received, TDIE is replaced with FCIE. When the transfer
is finally completed, SR_TDF is set but the interrupt handler isn't
called again.

Fixes: 6a130448498c ("spi: lpspi: Fix wrong transmission when don't use CONT")
Signed-off-by: Larisa Grigore <larisa.grigore@nxp.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20250828-james-nxp-lpspi-v2-1-6262b9aa9be4@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index f8cacb9c7408f3bd3ffe44bdacd21329c62c642b..50633115e83dd45bb11efff7d6756e842bef9a7a 100644 (file)
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -3,7 +3,7 @@
 // Freescale i.MX7ULP LPSPI driver
 //
 // Copyright 2016 Freescale Semiconductor, Inc.
-// Copyright 2018 NXP Semiconductors
+// Copyright 2018, 2023, 2025 NXP
 
 #include <linux/clk.h>
 #include <linux/completion.h>
@@ -780,7 +780,7 @@ static irqreturn_t fsl_lpspi_isr(int irq, void *dev_id)
        if (temp_SR & SR_MBF ||
            readl(fsl_lpspi->base + IMX7ULP_FSR) & FSR_TXCOUNT) {
                writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR);
-               fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE);
+               fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE | (temp_IER & IER_TDIE));
                return IRQ_HANDLED;
        }