Re: [PATCH v2] i2c: iproc: reset bus after timeout if START_BUSY is stuck

[Andi Shyti <andi.shyti@kernel.org>]

Hi Jonas,

...

> diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c
> index b5629cffe99b..86ca4c2221c4 100644
> --- a/drivers/i2c/busses/i2c-bcm-iproc.c
> +++ b/drivers/i2c/busses/i2c-bcm-iproc.c
> @@ -803,6 +803,17 @@ static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
>  	}
>  
>  	if (!time_left && !iproc_i2c->xfer_is_done) {
> +		/*
> +		 * The controller may fail to clear START_BUSY after a timeout,
> +		 * reset the controller to recover in that case.
> +		 */
> +		if (!!(iproc_i2c_rd_reg(iproc_i2c, M_CMD_OFFSET) &
> +		       BIT(M_CMD_START_BUSY_SHIFT))) {
> +			bcm_iproc_i2c_enable_disable(iproc_i2c, false);
> +			bcm_iproc_i2c_init(iproc_i2c);
> +			bcm_iproc_i2c_enable_disable(iproc_i2c, true);
> +		}
> +
>  		/* flush both TX/RX FIFOs */
>  		val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
>  		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);

the patch makes sense to me, but can I have an ack from the
Broadcom folks? Ray? Scott?

Thanks,
Andi