Re: [PATCH v1 1/2] i2c: spacemit: Avoid sleeping during bus reset in atomic context

[Alex Elder <elder@riscstar.com>]

On 11/10/26 12:14 AM, Anand Moon wrote:
> The spacemit_i2c_conditionally_reset_bus() function uses usleep_range()
> to wait after triggering a bus reset request. However, this function can
> be invoked during atomic I2C transfers (such as power-off or restart
> handlers running in atomic notifier chains), where sleeping is illegal.
> 
> Replace the sleep operation with the driver's internal helper,
> spacemit_i2c_delay(), which conditionally uses udelay() when running in
> an atomic context, avoiding "scheduling while atomic" bugs.
> 
> Assisted-by: LLM
> Cc: Troy Mitchell <troy.mitchell@linux.spacemit.com>
> Cc: Alex Elder <elder@riscstar.com>
> Signed-off-by: Anand Moon <linux.amoon@gmail.com>
> ---
>   drivers/i2c/busses/i2c-k1.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-k1.c b/drivers/i2c/busses/i2c-k1.c
> index ff32876e24d3..f4b21d7efaaf 100644
> --- a/drivers/i2c/busses/i2c-k1.c
> +++ b/drivers/i2c/busses/i2c-k1.c
> @@ -332,7 +332,7 @@ static void spacemit_i2c_conditionally_reset_bus(struct spacemit_i2c_dev *i2c)
>   		writel(FIELD_PREP(SPACEMIT_RCR_FIELD_RST_CYC, 1),
>   		       i2c->base + SPACEMIT_IRCR);
>   		writel(SPACEMIT_CR_RSTREQ, i2c->base + SPACEMIT_ICR);
> -		usleep_range(20, 30);
> +		spacemit_i2c_delay(i2c, 20);
>   	}
>   
>   	/* check sda again here */
> 
> base-commit: b3dfbde62cf1981c4638939c159dfd087b7a72e9

The use_pio flag is set for atomic transfers, so spacemit_i2c_delay()
will use udelay() regardless of the delay period.

Looks good.

Reviewed-by: Alex Elder <elder@riscstar.com>