dmaengine: ste_dma40: Check runtime PM in IRQ

d40_handle_interrupt() reads DMA40 interrupt registers unconditionally. A
spurious interrupt can arrive while the device is runtime suspended, after
dma40_runtime_suspend() has disabled the GCC clock.

Avoid touching the registers unless the device is runtime active by taking
a conditional runtime PM reference. Return IRQ_NONE when the device is
suspended, and drop the reference after handling an active interrupt.

When CONFIG_PM is disabled, pm_runtime_get_if_active() returns -EINVAL even
though the registers remain accessible. Keep handling interrupts in that
configuration and only drop the runtime PM reference when one was acquired.

Fixes: 7fb3e75e1833 ("dmaengine/ste_dma40: support pm in dma40")
Reported-by: sashiko-bot@kernel.org
Closes: https://lore.kernel.org/dmaengine/20260819225114.AE1511F000E9@smtp.kernel.org/
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Assisted-by: LLM
Signed-off-by: Linus Walleij <linusw@kernel.org>
Link: https://patch.msgid.link/20260927-dma40-fixes-v7-6-89f595e8851d@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

0 files changed, 0 insertions, 0 deletions