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@vger.kernel.org Reported-by: Chien Nguyen chien.nguyen.eb@rvc.renesas.com Signed-off-by: Chris Brandt chris.brandt@renesas.com
--- 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;