[char-misc-next 2/2] mei: cleanup status before client dma setup call

From: Tomas Winkler
Date: Thu Dec 23 2021 - 04:47:25 EST


From: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>

The upper layer may retry call to mei_cl_dma_alloc_and_map(),
in that case the client status may be non-zero after the previous call
and the wait condition will be true immediately.
Set cl->status to zero to allow waiting for an actual result
from the firmware.

Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
---
drivers/misc/mei/client.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index 96f4e59c32a5..22be86a205bf 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -2327,6 +2327,8 @@ int mei_cl_dma_alloc_and_map(struct mei_cl *cl, const struct file *fp,
list_move_tail(&cb->list, &dev->ctrl_rd_list);
}

+ cl->status = 0;
+
mutex_unlock(&dev->device_lock);
wait_event_timeout(cl->wait,
cl->dma_mapped || cl->status,
@@ -2404,6 +2406,8 @@ int mei_cl_dma_unmap(struct mei_cl *cl, const struct file *fp)
list_move_tail(&cb->list, &dev->ctrl_rd_list);
}

+ cl->status = 0;
+
mutex_unlock(&dev->device_lock);
wait_event_timeout(cl->wait,
!cl->dma_mapped || cl->status,
--
2.31.1