> From: Clark Wang <xiaoning.wang@xxxxxxx>
> Sent: Wednesday, March 17, 2021 2:54 PM
>
> A NACK flag in ISR means i2c bus error. In such codition, there is no need to do
> read/write operation. It's better to return ISR directly and then stop i2c
> transfer.
>
> Signed-off-by: Gao Pan <pandy.gao@xxxxxxx>
> Signed-off-by: Clark Wang <xiaoning.wang@xxxxxxx>
Reviewed-by: Dong Aisheng <aisheng.dong@xxxxxxx>
Regards
Aisheng
> ---
> drivers/i2c/busses/i2c-imx-lpi2c.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c
> b/drivers/i2c/busses/i2c-imx-lpi2c.c
> index 9db6ccded5e9..bbf44ac95021 100644
> --- a/drivers/i2c/busses/i2c-imx-lpi2c.c
> +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
> @@ -507,15 +507,17 @@ static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id)
> lpi2c_imx_intctrl(lpi2c_imx, 0);
> temp = readl(lpi2c_imx->base + LPI2C_MSR);
>
> + if (temp & MSR_NDF) {
> + complete(&lpi2c_imx->complete);
> + goto ret;
> + }
> +
> if (temp & MSR_RDF)
> lpi2c_imx_read_rxfifo(lpi2c_imx);
> -
> - if (temp & MSR_TDF)
> + else if (temp & MSR_TDF)
> lpi2c_imx_write_txfifo(lpi2c_imx);
>
> - if (temp & MSR_NDF)
> - complete(&lpi2c_imx->complete);
> -
> +ret:
> return IRQ_HANDLED;
> }
>
> --
> 2.25.1
