On Wed, Sep 25, 2019 at 02:43:27PM -0500, Chris Brandt wrote:
> 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")
> Reported-by: Chien Nguyen <chien.nguyen.eb@xxxxxxxxxxxxxxx>
> Signed-off-by: Chris Brandt <chris.brandt@xxxxxxxxxxx>
> ---
> 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
>
<formletter>
This is not the correct way to submit patches for inclusion in the
stable kernel tree. Please read:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.
</formletter>
