| From a71e2ac1f32097fbb2beab098687a7a95c84543e Mon Sep 17 00:00:00 2001 |
| From: Chris Brandt <chris.brandt@renesas.com> |
| Date: Thu, 26 Sep 2019 07:19:09 -0500 |
| Subject: i2c: riic: Clear NACK in tend isr |
| |
| From: Chris Brandt <chris.brandt@renesas.com> |
| |
| commit a71e2ac1f32097fbb2beab098687a7a95c84543e upstream. |
| |
| 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> |
| Signed-off-by: Wolfram Sang <wsa@the-dreams.de> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/i2c/busses/i2c-riic.c | 1 + |
| 1 file changed, 1 insertion(+) |
| |
| --- a/drivers/i2c/busses/i2c-riic.c |
| +++ b/drivers/i2c/busses/i2c-riic.c |
| @@ -212,6 +212,7 @@ static irqreturn_t riic_tend_isr(int irq |
| 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; |
