Re: [PATCH v6 21/23] dmaengine: ste_dma40: Search all blocks for fixed logical channels

[Frank Li <Frank.li@oss.nxp.com>]

On Thu, Sep 24, 2026 at 10:35:33AM +0200, Linus Walleij wrote:
> Fixed logical channel allocation scans physical channels in blocks of
> eight. When the requested physical channel does not belong to the first
> block, d40_allocate_channel() returns -EINVAL instead of checking later
> blocks.
>
> Skip nonmatching blocks so controllers with more than eight physical
> channels can allocate fixed logical channels from the later blocks.
>
> Fixes: 5cd326fd27da ("dmaengine/ste_dma40: allow fixed physical channel")
> Reported-by: sashiko-bot@kernel.org
> Closes: https://lore.kernel.org/dmaengine/20260819225008.5F9651F000E9@smtp.kernel.org/
> Assisted-by: LLM
> Signed-off-by: Linus Walleij <linusw@kernel.org>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/dma/ste_dma40.c | 7 ++-----
>  1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
> index d3d79e394d02..def2416fb1d0 100644
> --- a/drivers/dma/ste_dma40.c
> +++ b/drivers/dma/ste_dma40.c
> @@ -2111,11 +2111,8 @@ static int d40_allocate_channel(struct d40_chan *d40c, bool *first_phy_user)
>  		if (d40c->dma_cfg.use_fixed_channel) {
>  			i = d40c->dma_cfg.phy_channel;
>
> -			if ((i != phy_num) && (i != phy_num + 1)) {
> -				dev_err(chan2dev(d40c),
> -					"invalid fixed phy channel %d\n", i);
> -				return -EINVAL;
> -			}
> +			if (i != phy_num && i != phy_num + 1)
> +				continue;
>
>  			if (d40_alloc_mask_set(&phys[i], is_src, event_line,
>  					       is_log, first_phy_user))
>
> --
> 2.55.0
>