dmaengine: ste_dma40: Fix event group bounds

The dev_type validation can allow values whose derived event group has no
matching physical channel pair. d40_allocate_channel() then indexes
phy_res with j + event_group * 2, and __d40_set_prio_rt() uses the same
group to select priority and realtime registers.

The physical-mode validation also compares dev_type with the number of
physical channels. However, dev_type identifies an event line: DB8500 has
eight physical channels but 64 source and 64 destination event lines. The
event group determines which physical channel pair can serve an event, so
the physical channel count is not a valid dev_type limit.

Reject dev_type values outside the hardware event-group range, remove the
incorrect physical channel count limit, and stop the physical-channel
search before a partial final channel group can index past phy_res.

Fixes: 26955c07dcf3 ("dmaengine: ste_dma40: Amalgamate DMA source and destination channel numbers")
Reported-by: sashiko-bot@kernel.org
Closes: https://lore.kernel.org/dmaengine/20260819225008.5F9651F000E9@smtp.kernel.org/
Assisted-by: LLM
Link: https://lore.kernel.org/dmaengine/20260819225008.5F9651F000E9@smtp.kernel.org/
Signed-off-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20260927-dma40-fixes-v7-20-89f595e8851d@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

0 files changed, 0 insertions, 0 deletions