Re: [PATCH 7/8] i2c: sprd: Set I2C_RX_ACK when clear irq

[Andi Shyti]

Hi Huangzheng,

On Thu, Aug 17, 2023 at 05:45:19PM +0800, Huangzheng Lai wrote:
> We found that when clearing the I2C_TX_ACK bit, the I2C_MODE bit will

where is the I2C_TX_ACK bit cleared?

> also be cleared to 0. When the IIC master reads data, this situation
> will cause the FIFO of the IIC to be empty after clearing the interrupt.

Still I am not understanding the situation. In the clear_irq you
don't seem to do anything with the TX_ACK.

> To address this issue, when clearing interrupts, set I2C_RX_ACK bit to 1,
> as writing 1 to this bit will not take effect.

writing 1 to which bit?

Andi

> 
> Signed-off-by: Huangzheng Lai <Huangzheng.Lai@xxxxxxxxxx>
> ---
>  drivers/i2c/busses/i2c-sprd.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c
> index d867389c7f17..6f65f28ea69d 100644
> --- a/drivers/i2c/busses/i2c-sprd.c
> +++ b/drivers/i2c/busses/i2c-sprd.c
> @@ -138,7 +138,7 @@ static void sprd_i2c_clear_irq(struct sprd_i2c *i2c_dev)
>  {
>  	u32 tmp = readl(i2c_dev->base + I2C_STATUS);
>  
> -	writel(tmp & ~I2C_INT, i2c_dev->base + I2C_STATUS);
> +	writel((tmp & ~I2C_INT) | I2C_RX_ACK, i2c_dev->base + I2C_STATUS);
>  }
>  
>  static void sprd_i2c_reset_fifo(struct sprd_i2c *i2c_dev)
> -- 
> 2.17.1
>