path: root/drivers
diff options
authorChris Brandt <>2019-09-26 07:19:09 -0500
committerWolfram Sang <>2019-09-28 20:44:12 +0200
commita71e2ac1f32097fbb2beab098687a7a95c84543e (patch)
tree0abdf47803a81d7e2bae28f50351d7ad65bd1c76 /drivers
parent127068abe85bf3dee50df51cb039a5a987a4a666 (diff)
i2c: riic: Clear NACK in tend isr
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: Reported-by: Chien Nguyen <> Signed-off-by: Chris Brandt <> Signed-off-by: Wolfram Sang <>
Diffstat (limited to 'drivers')
1 files changed, 1 insertions, 0 deletions
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;