The NACKF flag should be cleared in INTRIICNAKI interrupt processing as
description in HW manual.
This issue shows up quickly when PREEMPT_RT is applied and a device is
probed that is not plugged in (like a touchscreen controller). The result
is endless interrupts that halt system boot.
Fixes: 310c18a41450 ("i2c: riic: add driver")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Chien Nguyen <chien.nguyen.eb@xxxxxxxxxxxxxxx>
Signed-off-by: Chris Brandt <chris.brandt@xxxxxxxxxxx>
---
v2:
* Added Cc for stable
---
drivers/i2c/busses/i2c-riic.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c
index f31413fd9521..800414886f6b 100644
--- a/drivers/i2c/busses/i2c-riic.c
+++ b/drivers/i2c/busses/i2c-riic.c
@@ -202,6 +202,7 @@ static irqreturn_t riic_tend_isr(int irq, void *data)
if (readb(riic->base + RIIC_ICSR2) & ICSR2_NACKF) {
/* We got a NACKIE */
readb(riic->base + RIIC_ICDRR); /* dummy read */
+ riic_clear_set_bit(riic, ICSR2_NACKF, 0, RIIC_ICSR2);
riic->err = -ENXIO;
} else if (riic->bytes_left) {
return IRQ_NONE;
--
2.23.0
