[PATCH V5 04/17] i3c: mipi-i3c-hci: Wait for DMA ring restart to complete
Adrian Hunter <[email protected]>
| Newsgroups | org.infradead.lists.linux-i3c,org.kernel.vger.linux-kernel |
|---|---|
| Organization | Intel Finland Oy, Registered Address: c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo, Business Identity Code: 0357606 - 4, Domiciled in Helsinki |
| Message-ID | <[email protected]> |
Although hci_dma_dequeue_xfer() is serialized against itself via control_mutex, this does not guarantee that a DMA ring restart triggered by a previous invocation has fully completed. When the function is called again in rapid succession, the DMA ring may still be transitioning back to the running state, which may confound or disrupt further state changes. Address this by waiting for the DMA ring restart to complete before continuing. Signed-off-by: Adrian Hunter <[email protected]> Reviewed-by: Frank Li <[email protected]> --- Changes in V5: None Changes in V4: Add Frank's Rev'd-by Changes in V2 and V3: None drivers/i3c/master/mipi-i3c-hci/dma.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c index c3da6eab8eae..3b14bc87bdf6 100644 --- a/drivers/i3c/master/mipi-i3c-hci/dma.c +++ b/drivers/i3c/master/mipi-i3c-hci/dma.c @@ -617,6 +617,7 @@ static bool hci_dma_dequeue_xfer(struct i3c_hci *hci, } /* restart the ring */ + reinit_completion(&rh->op_done); mipi_i3c_hci_resume(hci); rh_reg_write(RING_CONTROL, RING_CTRL_ENABLE); rh_reg_write(RING_CONTROL, RING_CTRL_ENABLE | RING_CTRL_RUN_STOP); @@ -625,6 +626,8 @@ static bool hci_dma_dequeue_xfer(struct i3c_hci *hci, spin_unlock_irq(&hci->lock); + wait_for_completion_timeout(&rh->op_done, HZ); + return did_unqueue; } -- 2.51.0 -- linux-i3c mailing list [email protected] http://lists.infradead.org/mailman/listinfo/linux-i3c