From: Adrian Hunter Date: Wed, 3 Jun 2026 09:07:39 +0000 (+0300) Subject: i3c: mipi-i3c-hci: Preserve RUN bit when aborting DMA ring X-Git-Url: http://git.ipfire.org/index.cgi?a=commitdiff_plain;h=093eb8e73c90aa0c8cfb0421aa85bd70c23488be;p=thirdparty%2Fkernel%2Flinux.git i3c: mipi-i3c-hci: Preserve RUN bit when aborting DMA ring The MIPI I3C HCI specification does not require the DMA ring RUN bit (RUN_STOP) to be cleared when issuing an ABORT. That allows the DMA ring to continue to receive IBIs, although an IBI is anyway not lost because it can be received once the ring restarts if the I3C device has not given up. Note, currently ABORT is only used on a timeout error path so the change has very little effect in practice. In the more common case of a transfer error, the ring (bundle) operation is halted by the controller anyway. Adjust the RING_CONTROL handling to set ABORT without clearing RUN_STOP, bringing the driver into alignment with the specification. Fixes: b795e68bf3073 ("i3c: mipi-i3c-hci: Correct RING_CTRL_ABORT handling in DMA dequeue") Signed-off-by: Adrian Hunter Reviewed-by: Frank Li Link: https://patch.msgid.link/20260603090754.16252-3-adrian.hunter@intel.com Signed-off-by: Alexandre Belloni --- diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c index e4daaa612055..bdffdd8b8923 100644 --- a/drivers/i3c/master/mipi-i3c-hci/dma.c +++ b/drivers/i3c/master/mipi-i3c-hci/dma.c @@ -554,7 +554,7 @@ static bool hci_dma_dequeue_xfer(struct i3c_hci *hci, if (ring_status & RING_STATUS_RUNNING) { /* stop the ring */ reinit_completion(&rh->op_done); - rh_reg_write(RING_CONTROL, RING_CTRL_ENABLE | RING_CTRL_ABORT); + rh_reg_write(RING_CONTROL, rh_reg_read(RING_CONTROL) | RING_CTRL_ABORT); wait_for_completion_timeout(&rh->op_done, HZ); ring_status = rh_reg_read(RING_STATUS); if (ring_status & RING_STATUS_RUNNING) {