[PATCH v4 21/23] dmaengine: ste_dma40: Search all blocks for fixed logical channels

[Linus Walleij <linusw@kernel.org>]

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>
---
 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 1738a37da682..d68828acb186 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -2077,11 +2077,8 @@ 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