dmaengine: dw-edma: Add core quiesce operations

Add core operations that quiesce only the resources represented by a
dw-edma instance, separate from the existing full controller off path.

For unrolled eDMA, quiesce masks the direction, disables ENGINE_EN,
waits for it to read back clear, then clears pending interrupt status.
If ENGINE_EN does not clear, return the timeout to the caller.
HDMA compatibility mode does not implement ENGINE_EN, so quiesce clears
CHi_PWR_EN for each represented channel instead. Both register maps
share interrupt control per direction, so quiescing one channel
quiesces the whole direction. Callers must own that direction and stop
the peer from programming it first.

HDMA native has per-channel registers and can quiesce the represented
channel directly.

No caller is added yet, so this is a no-functional-change preparation
for delegated channel reclaim and partial-owned remove paths.

Signed-off-by: Koichiro Den <den@valinux.co.jp>
Link: https://patch.msgid.link/20260721062815.4117887-4-den@valinux.co.jp
Signed-off-by: Vinod Koul <vkoul@kernel.org>

0 files changed, 0 insertions, 0 deletions